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[Xen-changelog] The patch removes broken, and very complicated malloc in

From: Xen patchbot -unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>

Date: Fri, 26 Aug 2005 10:36:15 +0000

Delivery-date: Fri, 26 Aug 2005 10:34:44 +0000

List-id: BK change log <xen-changelog.lists.xensource.com>

# HG changeset patch # User kaf24@xxxxxxxxxxxxxxxxxxxx # Node ID 581be7c5e9e4e1ff2ba29561478786d4b4f59465 # Parent 83c73802f02a0841d3ad697273de76654527f24b The patch removes broken, and very complicated malloc in favour of much simpler (and working) Xen's allocator (xmalloc by Rusty). Signed-off-by: Grzegorz Milos <gm281@xxxxxxxxx> diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/include/lib.h --- a/extras/mini-os/include/lib.h Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/include/lib.h Fri Aug 26 10:35:36 2005 @@ -79,36 +79,4 @@ char *strstr(const char *s1, const char *s2); -/* dlmalloc functions */ -struct mallinfo { - int arena; /* non-mmapped space allocated from system */ - int ordblks; /* number of free chunks */ - int smblks; /* number of fastbin blocks */ - int hblks; /* number of mmapped regions */ - int hblkhd; /* space in mmapped regions */ - int usmblks; /* maximum total allocated space */ - int fsmblks; /* space available in freed fastbin blocks */ - int uordblks; /* total allocated space */ - int fordblks; /* total free space */ - int keepcost; /* top-most, releasable (via malloc_trim) space */ -}; - -void *malloc(size_t n); -void *calloc(size_t n_elements, size_t element_size); -void free(void* p); -void *realloc(void* p, size_t n); -void *memalign(size_t alignment, size_t n); -void *valloc(size_t n); -struct mallinfo mallinfo(void); -int mallopt(int parameter_number, int parameter_value); - -void **independent_calloc(size_t n_elements, size_t size, void* chunks[]); -void **independent_comalloc(size_t n_elements, size_t sizes[], void* chunks[]); -void *pvalloc(size_t n); -void cfree(void* p); -int malloc_trim(size_t pad); -size_t malloc_usable_size(void* p); -void malloc_stats(void); - - #endif /* _LIB_H_ */ diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/include/mm.h --- a/extras/mini-os/include/mm.h Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/include/mm.h Fri Aug 26 10:35:36 2005 @@ -126,6 +126,18 @@ void init_mm(void); unsigned long alloc_pages(int order); -int is_mfn_mapped(unsigned long mfn); +#define alloc_page() alloc_pages(0); +void free_pages(void *pointer, int order); +//int is_mfn_mapped(unsigned long mfn); + +static __inline__ int get_order(unsigned long size) +{ + int order; + size = (size-1) >> PAGE_SHIFT; + for ( order = 0; size; order++ ) + size >>= 1; + return order; +} + #endif /* _MM_H_ */ diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/include/types.h --- a/extras/mini-os/include/types.h Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/include/types.h Fri Aug 26 10:35:36 2005 @@ -49,4 +49,6 @@ typedef unsigned long u_quad_t; typedef unsigned long uintptr_t; #endif + +#define UINT_MAX (~0U) #endif /* _TYPES_H_ */ diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/mm.c --- a/extras/mini-os/mm.c Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/mm.c Fri Aug 26 10:35:36 2005 @@ -1,6 +1,7 @@ -/* -*- Mode:C; c-basic-offset:4; tab-width:4 -*- +/* **************************************************************************** * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge + * (C) 2005 - Grzegorz Milos - Intel Research Cambridge **************************************************************************** * * File: mm.c @@ -13,8 +14,6 @@ * Description: memory management related functions * contains buddy page allocator from Xen. * - **************************************************************************** - * $Id: c-insert.c,v 1.7 2002/11/08 16:04:34 rn Exp $ **************************************************************************** * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to @@ -40,7 +39,7 @@ #include <mm.h> #include <types.h> #include <lib.h> - +#include <xmalloc.h> #ifdef MM_DEBUG #define DEBUG(_f, _a...) \ @@ -505,6 +504,6 @@ (u_long)to_virt(PFN_PHYS(max_pfn)), PFN_PHYS(max_pfn)); init_page_allocator(PFN_PHYS(start_pfn), PFN_PHYS(max_pfn)); #endif - + printk("MM: done\n"); } diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/include/xmalloc.h --- /dev/null Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/include/xmalloc.h Fri Aug 26 10:35:36 2005 @@ -0,0 +1,23 @@ +#ifndef __XMALLOC_H__ +#define __XMALLOC_H__ + +/* Allocate space for typed object. */ +#define xmalloc(_type) ((_type *)_xmalloc(sizeof(_type), __alignof__(_type))) + +/* Allocate space for array of typed objects. */ +#define xmalloc_array(_type, _num) ((_type *)_xmalloc_array(sizeof(_type), __alignof__(_type), _num)) + +/* Free any of the above. */ +extern void xfree(const void *); + +/* Underlying functions */ +extern void *_xmalloc(size_t size, size_t align); +static inline void *_xmalloc_array(size_t size, size_t align, size_t num) +{ + /* Check for overflow. */ + if (size && num > UINT_MAX / size) + return NULL; + return _xmalloc(size * num, align); +} + +#endif /* __XMALLOC_H__ */ diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/lib/xmalloc.c --- /dev/null Fri Aug 26 09:29:54 2005 +++ b/extras/mini-os/lib/xmalloc.c Fri Aug 26 10:35:36 2005 @@ -0,0 +1,219 @@ +/* + **************************************************************************** + * (C) 2005 - Grzegorz Milos - Intel Research Cambridge + **************************************************************************** + * + * File: xmaloc.c + * Author: Grzegorz Milos (gm281@xxxxxxxxx) + * Changes: + * + * Date: Aug 2005 + * + * Environment: Xen Minimal OS + * Description: simple memory allocator + * + **************************************************************************** + * Simple allocator for Mini-os. If larger than a page, simply use the + * page-order allocator. + * + * Copy of the allocator for Xen by Rusty Russell: + * Copyright (C) 2005 Rusty Russell IBM Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <os.h> +#include <mm.h> +#include <types.h> +#include <lib.h> +#include <list.h> + +static LIST_HEAD(freelist); +/* static spinlock_t freelist_lock = SPIN_LOCK_UNLOCKED; */ + +struct xmalloc_hdr +{ + /* Total including this hdr. */ + size_t size; + struct list_head freelist; +} __cacheline_aligned; + +static void maybe_split(struct xmalloc_hdr *hdr, size_t size, size_t block) +{ + struct xmalloc_hdr *extra; + size_t leftover = block - size; + + /* If enough is left to make a block, put it on free list. */ + if ( leftover >= (2 * sizeof(struct xmalloc_hdr)) ) + { + extra = (struct xmalloc_hdr *)((unsigned long)hdr + size); + extra->size = leftover; + list_add(&extra->freelist, &freelist); + } + else + { + size = block; + } + + hdr->size = size; + /* Debugging aid. */ + hdr->freelist.next = hdr->freelist.prev = NULL; +} + +static void *xmalloc_new_page(size_t size) +{ + struct xmalloc_hdr *hdr; + /* unsigned long flags; */ + + hdr = (struct xmalloc_hdr *)alloc_page(); + if ( hdr == NULL ) + return NULL; + + /* spin_lock_irqsave(&freelist_lock, flags); */ + maybe_split(hdr, size, PAGE_SIZE); + /* spin_unlock_irqrestore(&freelist_lock, flags); */ + + return hdr+1; +} + +/* Big object? Just use the page allocator. */ +static void *xmalloc_whole_pages(size_t size) +{ + struct xmalloc_hdr *hdr; + unsigned int pageorder = get_order(size); + + hdr = (struct xmalloc_hdr *)alloc_pages(pageorder); + if ( hdr == NULL ) + return NULL; + + hdr->size = (1 << (pageorder + PAGE_SHIFT)); + /* Debugging aid. */ + hdr->freelist.next = hdr->freelist.prev = NULL; + + return hdr+1; +} + +/* Return size, increased to alignment with align. */ +static inline size_t align_up(size_t size, size_t align) +{ + return (size + align - 1) & ~(align - 1); +} + +void *_xmalloc(size_t size, size_t align) +{ + struct xmalloc_hdr *i; + /* unsigned long flags; */ + + /* Add room for header, pad to align next header. */ + size += sizeof(struct xmalloc_hdr); + size = align_up(size, __alignof__(struct xmalloc_hdr)); + + /* For big allocs, give them whole pages. */ + if ( size >= PAGE_SIZE ) + return xmalloc_whole_pages(size); + + /* Search free list. */ + /* spin_lock_irqsave(&freelist_lock, flags); */ + list_for_each_entry( i, &freelist, freelist ) + { + if ( i->size < size ) + continue; + list_del(&i->freelist); + maybe_split(i, size, i->size); + /* spin_unlock_irqrestore(&freelist_lock, flags); */ + return i+1; + } + /* spin_unlock_irqrestore(&freelist_lock, flags); */ + + /* Alloc a new page and return from that. */ + return xmalloc_new_page(size); +} + +void xfree(const void *p) +{ + /* unsigned long flags; */ + struct xmalloc_hdr *i, *tmp, *hdr; + + if ( p == NULL ) + return; + + hdr = (struct xmalloc_hdr *)p - 1; + + /* We know hdr will be on same page. */ + if(((long)p & PAGE_MASK) != ((long)hdr & PAGE_MASK)) + { + printk("Header should be on the same page\n"); + *(int*)0=0; + } + + /* Not previously freed. */ + if(hdr->freelist.next || hdr->freelist.prev) + { + printk("Should not be previously freed\n"); + *(int*)0=0; + } + + /* Big allocs free directly. */ + if ( hdr->size >= PAGE_SIZE ) + { + free_pages(hdr, get_order(hdr->size)); + return; + } + + /* Merge with other free block, or put in list. */ + /* spin_lock_irqsave(&freelist_lock, flags); */ + list_for_each_entry_safe( i, tmp, &freelist, freelist ) + { + unsigned long _i = (unsigned long)i; + unsigned long _hdr = (unsigned long)hdr; + + /* Do not merge across page boundaries. */ + if ( ((_i ^ _hdr) & PAGE_MASK) != 0 ) + continue; + + /* We follow this block? Swallow it. */ + if ( (_i + i->size) == _hdr ) + { + list_del(&i->freelist); + i->size += hdr->size; + hdr = i; + } + + /* We precede this block? Swallow it. */ + if ( (_hdr + hdr->size) == _i ) + { + list_del(&i->freelist); + hdr->size += i->size; + } + } + + /* Did we merge an entire page? */ + if ( hdr->size == PAGE_SIZE ) + { + if((((unsigned long)hdr) & (PAGE_SIZE-1)) != 0) + { + printk("Bug\n"); + *(int*)0=0; + } + free_pages(hdr, 0); + } + else + { + list_add(&hdr->freelist, &freelist); + } + + /* spin_unlock_irqrestore(&freelist_lock, flags); */ +} + diff -r 83c73802f02a -r 581be7c5e9e4 extras/mini-os/lib/malloc.c --- a/extras/mini-os/lib/malloc.c Fri Aug 26 09:29:54 2005 +++ /dev/null Fri Aug 26 10:35:36 2005 @@ -1,5697 +0,0 @@ -/* -*- Mode:C; c-basic-offset:4; tab-width:4 -*- - **************************************************************************** - * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge - **************************************************************************** - * - * File: malloc.c - * Author: Rolf Neugebauer (neugebar@xxxxxxxxxxxxx) - * Changes: - * - * Date: Aug 2003 - * - * Environment: Xen Minimal OS - * Description: Library functions, maloc at al - * - **************************************************************************** - * $Id: c-insert.c,v 1.7 2002/11/08 16:04:34 rn Exp $ - **************************************************************************** - */ - -#include <os.h> -#include <mm.h> -#include <types.h> -#include <lib.h> - -/* standard compile option */ -#define HAVE_MEMCOPY 1 -#define USE_MEMCPY 1 -#undef HAVE_MMAP -#undef MMAP_CLEARS -#undef HAVE_MREMAP -#define malloc_getpagesize PAGE_SIZE -#undef HAVE_USR_INCLUDE_MALLOC_H -#define LACKS_UNISTD_H 1 -#define LACKS_SYS_PARAM_H 1 -#define LACKS_SYS_MMAN_H 1 -#define LACKS_FCNTL_H 1 - - -/* page allocator interface */ -#define MORECORE more_core -#define MORECORE_CONTIGUOUS 0 -#define MORECORE_FAILURE 0 -#define MORECORE_CANNOT_TRIM 1 - -static void *more_core(size_t n) -{ - static void *last; - unsigned long order, num_pages; - void *ret; - - if (n == 0) - return last; - - n = PFN_UP(n); - for ( order = 0; n > 1; order++ ) - n >>= 1; - ret = (void *)alloc_pages(order); - - /* work out pointer to end of chunk */ - if ( ret ) - { - num_pages = 1 << order; - last = (char *)ret + (num_pages * PAGE_SIZE); - } - - return ret; -} - -/* other options commented out below */ -#define __STD_C 1 -#define Void_t void -#define assert(x) ((void)0) - -#define CHUNK_SIZE_T unsigned long -#define PTR_UINT unsigned long -#define INTERNAL_SIZE_T size_t -#define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) -#define MALLOC_ALIGNMENT (2 * SIZE_SZ) -#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) -#define TRIM_FASTBINS 0 - -#define M_MXFAST 1 -#define DEFAULT_MXFAST 64 -#define M_TRIM_THRESHOLD -1 -#define DEFAULT_TRIM_THRESHOLD (256 * 1024) -#define M_TOP_PAD -2 -#define DEFAULT_TOP_PAD (0) -#define M_MMAP_THRESHOLD -3 -#define DEFAULT_MMAP_THRESHOLD (256 * 1024) -#define M_MMAP_MAX -4 -#define DEFAULT_MMAP_MAX (0) -#define MALLOC_FAILURE_ACTION printf("malloc failure\n") - -#define cALLOc public_cALLOc -#define fREe public_fREe -#define cFREe public_cFREe -#define mALLOc public_mALLOc -#define mEMALIGn public_mEMALIGn -#define rEALLOc public_rEALLOc -#define vALLOc public_vALLOc -#define pVALLOc public_pVALLOc -#define mALLINFo public_mALLINFo -#define mALLOPt public_mALLOPt -#define mTRIm public_mTRIm -#define mSTATs public_mSTATs -#define mUSABLe public_mUSABLe -#define iCALLOc public_iCALLOc -#define iCOMALLOc public_iCOMALLOc - -#define public_cALLOc calloc -#define public_fREe free -#define public_cFREe cfree -#define public_mALLOc malloc -#define public_mEMALIGn memalign -#define public_rEALLOc realloc -#define public_vALLOc valloc -#define public_pVALLOc pvalloc -#define public_mALLINFo mallinfo -#define public_mALLOPt mallopt -#define public_mTRIm malloc_trim -#define public_mSTATs malloc_stats -#define public_mUSABLe malloc_usable_size -#define public_iCALLOc independent_calloc -#define public_iCOMALLOc independent_comalloc - - -/* - This is a version (aka dlmalloc) of malloc/free/realloc written by - Doug Lea and released to the public domain. Use, modify, and - redistribute this code without permission or acknowledgement in any - way you wish. Send questions, comments, complaints, performance - data, etc to dl@xxxxxxxxxxxxx - -* VERSION 2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee) - - Note: There may be an updated version of this malloc obtainable at - ftp://gee.cs.oswego.edu/pub/misc/malloc.c - Check before installing! - -* Quickstart - - This library is all in one file to simplify the most common usage: - ftp it, compile it (-O), and link it into another program. All - of the compile-time options default to reasonable values for use on - most unix platforms. Compile -DWIN32 for reasonable defaults on windows. - You might later want to step through various compile-time and dynamic - tuning options. - - For convenience, an include file for code using this malloc is at: - ftp://gee.cs.oswego.edu/pub/misc/malloc-2.7.1.h - You don't really need this .h file unless you call functions not - defined in your system include files. The .h file contains only the - excerpts from this file needed for using this malloc on ANSI C/C++ - systems, so long as you haven't changed compile-time options about - naming and tuning parameters. If you do, then you can create your - own malloc.h that does include all settings by cutting at the point - indicated below. - -* Why use this malloc? - - This is not the fastest, most space-conserving, most portable, or - most tunable malloc ever written. However it is among the fastest - while also being among the most space-conserving, portable and tunable. - Consistent balance across these factors results in a good general-purpose - allocator for malloc-intensive programs. - - The main properties of the algorithms are: - * For large (>= 512 bytes) requests, it is a pure best-fit allocator, - with ties normally decided via FIFO (i.e. least recently used). - * For small (<= 64 bytes by default) requests, it is a caching - allocator, that maintains pools of quickly recycled chunks. - * In between, and for combinations of large and small requests, it does - the best it can trying to meet both goals at once. - * For very large requests (>= 128KB by default), it relies on system - memory mapping facilities, if supported. - - For a longer but slightly out of date high-level description, see - http://gee.cs.oswego.edu/dl/html/malloc.html - - You may already by default be using a C library containing a malloc - that is based on some version of this malloc (for example in - linux). You might still want to use the one in this file in order to - customize settings or to avoid overheads associated with library - versions. - -* Contents, described in more detail in "description of public routines" below. - - Standard (ANSI/SVID/...) functions: - malloc(size_t n); - calloc(size_t n_elements, size_t element_size); - free(Void_t* p); - realloc(Void_t* p, size_t n); - memalign(size_t alignment, size_t n); - valloc(size_t n); - mallinfo() - mallopt(int parameter_number, int parameter_value) - - Additional functions: - independent_calloc(size_t n_elements, size_t size, Void_t* chunks[]); - independent_comalloc(size_t n_elements, size_t sizes[], Void_t* chunks[]); - pvalloc(size_t n); - cfree(Void_t* p); - malloc_trim(size_t pad); - malloc_usable_size(Void_t* p); - malloc_stats(); - -* Vital statistics: - - Supported pointer representation: 4 or 8 bytes - Supported size_t representation: 4 or 8 bytes - Note that size_t is allowed to be 4 bytes even if pointers are 8. - You can adjust this by defining INTERNAL_SIZE_T - - Alignment: 2 * sizeof(size_t) (default) - (i.e., 8 byte alignment with 4byte size_t). This suffices for - nearly all current machines and C compilers. However, you can - define MALLOC_ALIGNMENT to be wider than this if necessary. - - Minimum overhead per allocated chunk: 4 or 8 bytes - Each malloced chunk has a hidden word of overhead holding size - and status information. - - Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead) - 8-byte ptrs: 24/32 bytes (including, 4/8 overhead) - - When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte - ptrs but 4 byte size) or 24 (for 8/8) additional bytes are - needed; 4 (8) for a trailing size field and 8 (16) bytes for - free list pointers. Thus, the minimum allocatable size is - 16/24/32 bytes. - - Even a request for zero bytes (i.e., malloc(0)) returns a - pointer to something of the minimum allocatable size. - - The maximum overhead wastage (i.e., number of extra bytes - allocated than were requested in malloc) is less than or equal - to the minimum size, except for requests >= mmap_threshold that - are serviced via mmap(), where the worst case wastage is 2 * - sizeof(size_t) bytes plus the remainder from a system page (the - minimal mmap unit); typically 4096 or 8192 bytes. - - Maximum allocated size: 4-byte size_t: 2^32 minus about two pages - 8-byte size_t: 2^64 minus about two pages - - It is assumed that (possibly signed) size_t values suffice to - represent chunk sizes. `Possibly signed' is due to the fact - that `size_t' may be defined on a system as either a signed or - an unsigned type. The ISO C standard says that it must be - unsigned, but a few systems are known not to adhere to this. - Additionally, even when size_t is unsigned, sbrk (which is by - default used to obtain memory from system) accepts signed - arguments, and may not be able to handle size_t-wide arguments - with negative sign bit. Generally, values that would - appear as negative after accounting for overhead and alignment - are supported only via mmap(), which does not have this - limitation. - - Requests for sizes outside the allowed range will perform an optional - failure action and then return null. (Requests may also - also fail because a system is out of memory.) - - Thread-safety: NOT thread-safe unless USE_MALLOC_LOCK defined - - When USE_MALLOC_LOCK is defined, wrappers are created to - surround every public call with either a pthread mutex or - a win32 spinlock (depending on WIN32). This is not - especially fast, and can be a major bottleneck. - It is designed only to provide minimal protection - in concurrent environments, and to provide a basis for - extensions. If you are using malloc in a concurrent program, - you would be far better off obtaining ptmalloc, which is - derived from a version of this malloc, and is well-tuned for - concurrent programs. (See http://www.malloc.de) Note that - even when USE_MALLOC_LOCK is defined, you can can guarantee - full thread-safety only if no threads acquire memory through - direct calls to MORECORE or other system-level allocators. - - Compliance: I believe it is compliant with the 1997 Single Unix Specification - (See http://www.opennc.org). Also SVID/XPG, ANSI C, and probably - others as well. - -* Synopsis of compile-time options: - - People have reported using previous versions of this malloc on all - versions of Unix, sometimes by tweaking some of the defines - below. It has been tested most extensively on Solaris and - Linux. It is also reported to work on WIN32 platforms. - People also report using it in stand-alone embedded systems. - - The implementation is in straight, hand-tuned ANSI C. It is not - at all modular. (Sorry!) It uses a lot of macros. To be at all - usable, this code should be compiled using an optimizing compiler - (for example gcc -O3) that can simplify expressions and control - paths. (FAQ: some macros import variables as arguments rather than - declare locals because people reported that some debuggers - otherwise get confused.) - - OPTION DEFAULT VALUE - - Compilation Environment options: - - __STD_C derived from C compiler defines - WIN32 NOT defined - HAVE_MEMCPY defined - USE_MEMCPY 1 if HAVE_MEMCPY is defined - HAVE_MMAP defined as 1 - MMAP_CLEARS 1 - HAVE_MREMAP 0 unless linux defined - malloc_getpagesize derived from system #includes, or 4096 if not - HAVE_USR_INCLUDE_MALLOC_H NOT defined - LACKS_UNISTD_H NOT defined unless WIN32 - LACKS_SYS_PARAM_H NOT defined unless WIN32 - LACKS_SYS_MMAN_H NOT defined unless WIN32 - LACKS_FCNTL_H NOT defined - - Changing default word sizes: - - INTERNAL_SIZE_T size_t - MALLOC_ALIGNMENT 2 * sizeof(INTERNAL_SIZE_T) - PTR_UINT unsigned long - CHUNK_SIZE_T unsigned long - - Configuration and functionality options: - - USE_DL_PREFIX NOT defined - USE_PUBLIC_MALLOC_WRAPPERS NOT defined - USE_MALLOC_LOCK NOT defined - DEBUG NOT defined - REALLOC_ZERO_BYTES_FREES NOT defined - MALLOC_FAILURE_ACTION errno = ENOMEM, if __STD_C defined, else no-op - TRIM_FASTBINS 0 - FIRST_SORTED_BIN_SIZE 512 - - Options for customizing MORECORE: - - MORECORE sbrk - MORECORE_CONTIGUOUS 1 - MORECORE_CANNOT_TRIM NOT defined - MMAP_AS_MORECORE_SIZE (1024 * 1024) - - Tuning options that are also dynamically changeable via mallopt: - - DEFAULT_MXFAST 64 - DEFAULT_TRIM_THRESHOLD 256 * 1024 - DEFAULT_TOP_PAD 0 - DEFAULT_MMAP_THRESHOLD 256 * 1024 - DEFAULT_MMAP_MAX 65536 - - There are several other #defined constants and macros that you - probably don't want to touch unless you are extending or adapting malloc. -*/ - -/* RN: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ -#if 0 - -/* - WIN32 sets up defaults for MS environment and compilers. - Otherwise defaults are for unix. -*/ - -/* #define WIN32 */ - -#ifdef WIN32 - -#define WIN32_LEAN_AND_MEAN -#include <windows.h> - -/* Win32 doesn't supply or need the following headers */ -#define LACKS_UNISTD_H -#define LACKS_SYS_PARAM_H -#define LACKS_SYS_MMAN_H - -/* Use the supplied emulation of sbrk */ -#define MORECORE sbrk -#define MORECORE_CONTIGUOUS 1 -#define MORECORE_FAILURE ((void*)(-1)) - -/* Use the supplied emulation of mmap and munmap */ -#define HAVE_MMAP 1 -#define MUNMAP_FAILURE (-1) -#define MMAP_CLEARS 1 - -/* These values don't really matter in windows mmap emulation */ -#define MAP_PRIVATE 1 -#define MAP_ANONYMOUS 2 -#define PROT_READ 1 -#define PROT_WRITE 2 - -/* Emulation functions defined at the end of this file */ - -/* If USE_MALLOC_LOCK, use supplied critical-section-based lock functions */ -#ifdef USE_MALLOC_LOCK -static int slwait(int *sl); -static int slrelease(int *sl); -#endif - -static long getpagesize(void); -static long getregionsize(void); -static void *sbrk(long size); -static void *mmap(void *ptr, long size, long prot, long type, long handle, long arg); -static long munmap(void *ptr, long size); - -static void vminfo (unsigned long*free, unsigned long*reserved, unsigned long*committed); -static int cpuinfo (int whole, unsigned long*kernel, unsigned long*user); - -#endif - -/* - __STD_C should be nonzero if using ANSI-standard C compiler, a C++ - compiler, or a C compiler sufficiently close to ANSI to get away - with it. -*/ - -#ifndef __STD_C -#if defined(__STDC__) || defined(_cplusplus) -#define __STD_C 1 -#else -#define __STD_C 0 -#endif -#endif /*__STD_C*/ - - -/* - Void_t* is the pointer type that malloc should say it returns -*/ - -#ifndef Void_t -#if (__STD_C || defined(WIN32)) -#define Void_t void -#else -#define Void_t char -#endif -#endif /*Void_t*/ - -#if __STD_C -#include <stddef.h> /* for size_t */ -#else -#include <sys/types.h> -#endif - -#ifdef __cplusplus -extern "C" { -#endif - -/* define LACKS_UNISTD_H if your system does not have a <unistd.h>. */ - -/* #define LACKS_UNISTD_H */ - -#ifndef LACKS_UNISTD_H -#include <unistd.h> -#endif - -/* define LACKS_SYS_PARAM_H if your system does not have a <sys/param.h>. */ - -/* #define LACKS_SYS_PARAM_H */ - - -#include <stdio.h> /* needed for malloc_stats */ -#include <errno.h> /* needed for optional MALLOC_FAILURE_ACTION */ - - -/* - Debugging: - - Because freed chunks may be overwritten with bookkeeping fields, this - malloc will often die when freed memory is overwritten by user - programs. This can be very effective (albeit in an annoying way) - in helping track down dangling pointers. - - If you compile with -DDEBUG, a number of assertion checks are - enabled that will catch more memory errors. You probably won't be - able to make much sense of the actual assertion errors, but they - should help you locate incorrectly overwritten memory. The - checking is fairly extensive, and will slow down execution - noticeably. Calling malloc_stats or mallinfo with DEBUG set will - attempt to check every non-mmapped allocated and free chunk in the - course of computing the summmaries. (By nature, mmapped regions - cannot be checked very much automatically.) - - Setting DEBUG may also be helpful if you are trying to modify - this code. The assertions in the check routines spell out in more - detail the assumptions and invariants underlying the algorithms. - - Setting DEBUG does NOT provide an automated mechanism for checking - that all accesses to malloced memory stay within their - bounds. However, there are several add-ons and adaptations of this - or other mallocs available that do this. -*/ - -#if DEBUG -#include <assert.h> -#else -#define assert(x) ((void)0) -#endif - -/* - The unsigned integer type used for comparing any two chunk sizes. - This should be at least as wide as size_t, but should not be signed. -*/ - -#ifndef CHUNK_SIZE_T -#define CHUNK_SIZE_T unsigned long -#endif - -/* - The unsigned integer type used to hold addresses when they are are - manipulated as integers. Except that it is not defined on all - systems, intptr_t would suffice. -*/ -#ifndef PTR_UINT -#define PTR_UINT unsigned long -#endif - - -/* - INTERNAL_SIZE_T is the word-size used for internal bookkeeping - of chunk sizes. - - The default version is the same as size_t. - - While not strictly necessary, it is best to define this as an - unsigned type, even if size_t is a signed type. This may avoid some - artificial size limitations on some systems. - - On a 64-bit machine, you may be able to reduce malloc overhead by - defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the - expense of not being able to handle more than 2^32 of malloced - space. If this limitation is acceptable, you are encouraged to set - this unless you are on a platform requiring 16byte alignments. In - this case the alignment requirements turn out to negate any - potential advantages of decreasing size_t word size. - - Implementors: Beware of the possible combinations of: - - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits, - and might be the same width as int or as long - - size_t might have different width and signedness as INTERNAL_SIZE_T - - int and long might be 32 or 64 bits, and might be the same width - To deal with this, most comparisons and difference computations - among INTERNAL_SIZE_Ts should cast them to CHUNK_SIZE_T, being - aware of the fact that casting an unsigned int to a wider long does - not sign-extend. (This also makes checking for negative numbers - awkward.) Some of these casts result in harmless compiler warnings - on some systems. -*/ - -#ifndef INTERNAL_SIZE_T -#define INTERNAL_SIZE_T size_t -#endif - -/* The corresponding word size */ -#define SIZE_SZ (sizeof(INTERNAL_SIZE_T)) - - - -/* - MALLOC_ALIGNMENT is the minimum alignment for malloc'ed chunks. - It must be a power of two at least 2 * SIZE_SZ, even on machines - for which smaller alignments would suffice. It may be defined as - larger than this though. Note however that code and data structures - are optimized for the case of 8-byte alignment. -*/ - - -#ifndef MALLOC_ALIGNMENT -#define MALLOC_ALIGNMENT (2 * SIZE_SZ) -#endif - -/* The corresponding bit mask value */ -#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1) - - - -/* - REALLOC_ZERO_BYTES_FREES should be set if a call to - realloc with zero bytes should be the same as a call to free. - Some people think it should. Otherwise, since this malloc - returns a unique pointer for malloc(0), so does realloc(p, 0). -*/ - -/* #define REALLOC_ZERO_BYTES_FREES */ - -/* - TRIM_FASTBINS controls whether free() of a very small chunk can - immediately lead to trimming. Setting to true (1) can reduce memory - footprint, but will almost always slow down programs that use a lot - of small chunks. - - Define this only if you are willing to give up some speed to more - aggressively reduce system-level memory footprint when releasing - memory in programs that use many small chunks. You can get - essentially the same effect by setting MXFAST to 0, but this can - lead to even greater slowdowns in programs using many small chunks. - TRIM_FASTBINS is an in-between compile-time option, that disables - only those chunks bordering topmost memory from being placed in - fastbins. -*/ - -#ifndef TRIM_FASTBINS -#define TRIM_FASTBINS 0 -#endif - - -/* - USE_DL_PREFIX will prefix all public routines with the string 'dl'. - This is necessary when you only want to use this malloc in one part - of a program, using your regular system malloc elsewhere. -*/ - -/* #define USE_DL_PREFIX */ - - -/* - USE_MALLOC_LOCK causes wrapper functions to surround each - callable routine with pthread mutex lock/unlock. - - USE_MALLOC_LOCK forces USE_PUBLIC_MALLOC_WRAPPERS to be defined -*/ - - -/* #define USE_MALLOC_LOCK */ - - -/* - If USE_PUBLIC_MALLOC_WRAPPERS is defined, every public routine is - actually a wrapper function that first calls MALLOC_PREACTION, then - calls the internal routine, and follows it with - MALLOC_POSTACTION. This is needed for locking, but you can also use - this, without USE_MALLOC_LOCK, for purposes of interception, - instrumentation, etc. It is a sad fact that using wrappers often - noticeably degrades performance of malloc-intensive programs. -*/ - -#ifdef USE_MALLOC_LOCK -#define USE_PUBLIC_MALLOC_WRAPPERS -#else -/* #define USE_PUBLIC_MALLOC_WRAPPERS */ -#endif - - -/* - Two-phase name translation. - All of the actual routines are given mangled names. - When wrappers are used, they become the public callable versions. - When DL_PREFIX is used, the callable names are prefixed. -*/ - -#ifndef USE_PUBLIC_MALLOC_WRAPPERS -#define cALLOc public_cALLOc -#define fREe public_fREe -#define cFREe public_cFREe -#define mALLOc public_mALLOc -#define mEMALIGn public_mEMALIGn -#define rEALLOc public_rEALLOc -#define vALLOc public_vALLOc -#define pVALLOc public_pVALLOc -#define mALLINFo public_mALLINFo -#define mALLOPt public_mALLOPt -#define mTRIm public_mTRIm -#define mSTATs public_mSTATs -#define mUSABLe public_mUSABLe -#define iCALLOc public_iCALLOc -#define iCOMALLOc public_iCOMALLOc -#endif - -#ifdef USE_DL_PREFIX -#define public_cALLOc dlcalloc -#define public_fREe dlfree -#define public_cFREe dlcfree -#define public_mALLOc dlmalloc -#define public_mEMALIGn dlmemalign -#define public_rEALLOc dlrealloc -#define public_vALLOc dlvalloc -#define public_pVALLOc dlpvalloc -#define public_mALLINFo dlmallinfo -#define public_mALLOPt dlmallopt -#define public_mTRIm dlmalloc_trim -#define public_mSTATs dlmalloc_stats -#define public_mUSABLe dlmalloc_usable_size -#define public_iCALLOc dlindependent_calloc -#define public_iCOMALLOc dlindependent_comalloc -#else /* USE_DL_PREFIX */ -#define public_cALLOc calloc -#define public_fREe free -#define public_cFREe cfree -#define public_mALLOc malloc -#define public_mEMALIGn memalign -#define public_rEALLOc realloc -#define public_vALLOc valloc -#define public_pVALLOc pvalloc -#define public_mALLINFo mallinfo -#define public_mALLOPt mallopt -#define public_mTRIm malloc_trim -#define public_mSTATs malloc_stats -#define public_mUSABLe malloc_usable_size -#define public_iCALLOc independent_calloc -#define public_iCOMALLOc independent_comalloc -#endif /* USE_DL_PREFIX */ - - -/* - HAVE_MEMCPY should be defined if you are not otherwise using - ANSI STD C, but still have memcpy and memset in your C library - and want to use them in calloc and realloc. Otherwise simple - macro versions are defined below. - - USE_MEMCPY should be defined as 1 if you actually want to - have memset and memcpy called. People report that the macro - versions are faster than libc versions on some systems. - - Even if USE_MEMCPY is set to 1, loops to copy/clear small chunks - (of <= 36 bytes) are manually unrolled in realloc and calloc. -*/ - -#define HAVE_MEMCPY - -#ifndef USE_MEMCPY -#ifdef HAVE_MEMCPY -#define USE_MEMCPY 1 -#else -#define USE_MEMCPY 0 -#endif -#endif - - -#if (__STD_C || defined(HAVE_MEMCPY)) - -#ifdef WIN32 -/* On Win32 memset and memcpy are already declared in windows.h */ -#else -#if __STD_C -void* memset(void*, int, size_t); -void* memcpy(void*, const void*, size_t); -#else -Void_t* memset(); -Void_t* memcpy(); -#endif -#endif -#endif - -/* - MALLOC_FAILURE_ACTION is the action to take before "return 0" when - malloc fails to be able to return memory, either because memory is - exhausted or because of illegal arguments. - - By default, sets errno if running on STD_C platform, else does nothing. -*/ - -#ifndef MALLOC_FAILURE_ACTION -#if __STD_C -#define MALLOC_FAILURE_ACTION \ - errno = ENOMEM; - -#else -#define MALLOC_FAILURE_ACTION -#endif -#endif - -/* - MORECORE-related declarations. By default, rely on sbrk -*/ - - -#ifdef LACKS_UNISTD_H -#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) -#if __STD_C -extern Void_t* sbrk(ptrdiff_t); -#else -extern Void_t* sbrk(); -#endif -#endif -#endif - -/* - MORECORE is the name of the routine to call to obtain more memory - from the system. See below for general guidance on writing - alternative MORECORE functions, as well as a version for WIN32 and a - sample version for pre-OSX macos. -*/ - -#ifndef MORECORE -#define MORECORE sbrk -#endif - -/* - MORECORE_FAILURE is the value returned upon failure of MORECORE - as well as mmap. Since it cannot be an otherwise valid memory address, - and must reflect values of standard sys calls, you probably ought not - try to redefine it. -*/ - -#ifndef MORECORE_FAILURE -#define MORECORE_FAILURE (-1) -#endif - -/* - If MORECORE_CONTIGUOUS is true, take advantage of fact that - consecutive calls to MORECORE with positive arguments always return - contiguous increasing addresses. This is true of unix sbrk. Even - if not defined, when regions happen to be contiguous, malloc will - permit allocations spanning regions obtained from different - calls. But defining this when applicable enables some stronger - consistency checks and space efficiencies. -*/ - -#ifndef MORECORE_CONTIGUOUS -#define MORECORE_CONTIGUOUS 1 -#endif - -/* - Define MORECORE_CANNOT_TRIM if your version of MORECORE - cannot release space back to the system when given negative - arguments. This is generally necessary only if you are using - a hand-crafted MORECORE function that cannot handle negative arguments. -*/ - -/* #define MORECORE_CANNOT_TRIM */ - - -/* - Define HAVE_MMAP as true to optionally make malloc() use mmap() to - allocate very large blocks. These will be returned to the - operating system immediately after a free(). Also, if mmap - is available, it is used as a backup strategy in cases where - MORECORE fails to provide space from system. - - This malloc is best tuned to work with mmap for large requests. - If you do not have mmap, operations involving very large chunks (1MB - or so) may be slower than you'd like. -*/ - -#ifndef HAVE_MMAP -#define HAVE_MMAP 1 -#endif - -#if HAVE_MMAP -/* - Standard unix mmap using /dev/zero clears memory so calloc doesn't - need to. -*/ - -#ifndef MMAP_CLEARS -#define MMAP_CLEARS 1 -#endif - -#else /* no mmap */ -#ifndef MMAP_CLEARS -#define MMAP_CLEARS 0 -#endif -#endif - - -/* - MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if - sbrk fails, and mmap is used as a backup (which is done only if - HAVE_MMAP). The value must be a multiple of page size. This - backup strategy generally applies only when systems have "holes" in - address space, so sbrk cannot perform contiguous expansion, but - there is still space available on system. On systems for which - this is known to be useful (i.e. most linux kernels), this occurs - only when programs allocate huge amounts of memory. Between this, - and the fact that mmap regions tend to be limited, the size should - be large, to avoid too many mmap calls and thus avoid running out - of kernel resources. -*/ - -#ifndef MMAP_AS_MORECORE_SIZE -#define MMAP_AS_MORECORE_SIZE (1024 * 1024) -#endif - -/* - Define HAVE_MREMAP to make realloc() use mremap() to re-allocate - large blocks. This is currently only possible on Linux with - kernel versions newer than 1.3.77. -*/ - -#ifndef HAVE_MREMAP -#ifdef linux -#define HAVE_MREMAP 1 -#else -#define HAVE_MREMAP 0 -#endif - -#endif /* HAVE_MMAP */ - - -/* - The system page size. To the extent possible, this malloc manages - memory from the system in page-size units. Note that this value is - cached during initialization into a field of malloc_state. So even - if malloc_getpagesize is a function, it is only called once. - - The following mechanics for getpagesize were adapted from bsd/gnu - getpagesize.h. If none of the system-probes here apply, a value of - 4096 is used, which should be OK: If they don't apply, then using - the actual value probably doesn't impact performance. -*/ - - -#ifndef malloc_getpagesize - -#ifndef LACKS_UNISTD_H -# include <unistd.h> -#endif - -# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ -# ifndef _SC_PAGE_SIZE -# define _SC_PAGE_SIZE _SC_PAGESIZE -# endif -# endif - -# ifdef _SC_PAGE_SIZE -# define malloc_getpagesize sysconf(_SC_PAGE_SIZE) -# else -# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) - extern size_t getpagesize(); -# define malloc_getpagesize getpagesize() -# else -# ifdef WIN32 /* use supplied emulation of getpagesize */ -# define malloc_getpagesize getpagesize() -# else -# ifndef LACKS_SYS_PARAM_H -# include <sys/param.h> -# endif -# ifdef EXEC_PAGESIZE -# define malloc_getpagesize EXEC_PAGESIZE -# else -# ifdef NBPG -# ifndef CLSIZE -# define malloc_getpagesize NBPG -# else -# define malloc_getpagesize (NBPG * CLSIZE) -# endif -# else -# ifdef NBPC -# define malloc_getpagesize NBPC -# else -# ifdef PAGESIZE -# define malloc_getpagesize PAGESIZE -# else /* just guess */ -# define malloc_getpagesize (4096) -# endif -# endif -# endif -# endif -# endif -# endif -# endif -#endif - -/* - This version of malloc supports the standard SVID/XPG mallinfo - routine that returns a struct containing usage properties and - statistics. It should work on any SVID/XPG compliant system that has - a /usr/include/malloc.h defining struct mallinfo. (If you'd like to - install such a thing yourself, cut out the preliminary declarations - as described above and below and save them in a malloc.h file. But - there's no compelling reason to bother to do this.) - - The main declaration needed is the mallinfo struct that is returned - (by-copy) by mallinfo(). The SVID/XPG malloinfo struct contains a - bunch of fields that are not even meaningful in this version of - malloc. These fields are are instead filled by mallinfo() with - other numbers that might be of interest. - - HAVE_USR_INCLUDE_MALLOC_H should be set if you have a - /usr/include/malloc.h file that includes a declaration of struct - mallinfo. If so, it is included; else an SVID2/XPG2 compliant - version is declared below. These must be precisely the same for - mallinfo() to work. The original SVID version of this struct, - defined on most systems with mallinfo, declares all fields as - ints. But some others define as unsigned long. If your system - defines the fields using a type of different width than listed here, - you must #include your system version and #define - HAVE_USR_INCLUDE_MALLOC_H. -*/ - -/* #define HAVE_USR_INCLUDE_MALLOC_H */ - -#ifdef HAVE_USR_INCLUDE_MALLOC_H -#include "/usr/include/malloc.h" -#else - -/* SVID2/XPG mallinfo structure */ - -struct mallinfo { - int arena; /* non-mmapped space allocated from system */ - int ordblks; /* number of free chunks */ - int smblks; /* number of fastbin blocks */ - int hblks; /* number of mmapped regions */ - int hblkhd; /* space in mmapped regions */ - int usmblks; /* maximum total allocated space */ - int fsmblks; /* space available in freed fastbin blocks */ - int uordblks; /* total allocated space */ - int fordblks; /* total free space */ - int keepcost; /* top-most, releasable (via malloc_trim) space */ -}; - -/* - SVID/XPG defines four standard parameter numbers for mallopt, - normally defined in malloc.h. Only one of these (M_MXFAST) is used - in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, - so setting them has no effect. But this malloc also supports other - options in mallopt described below. -*/ -#endif - - -/* ---------- description of public routines ------------ */ - -/* - malloc(size_t n) - Returns a pointer to a newly allocated chunk of at least n bytes, or null - if no space is available. Additionally, on failure, errno is - set to ENOMEM on ANSI C systems. - - If n is zero, malloc returns a minumum-sized chunk. (The minimum - size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit - systems.) On most systems, size_t is an unsigned type, so calls - with negative arguments are interpreted as requests for huge amounts - of space, which will often fail. The maximum supported value of n - differs across systems, but is in all cases less than the maximum - representable value of a size_t. -*/ -#if __STD_C -Void_t* public_mALLOc(size_t); -#else -Void_t* public_mALLOc(); -#endif - -/* - free(Void_t* p) - Releases the chunk of memory pointed to by p, that had been previously - allocated using malloc or a related routine such as realloc. - It has no effect if p is null. It can have arbitrary (i.e., bad!) - effects if p has already been freed. - - Unless disabled (using mallopt), freeing very large spaces will - when possible, automatically trigger operations that give - back unused memory to the system, thus reducing program footprint. -*/ -#if __STD_C -void public_fREe(Void_t*); -#else -void public_fREe(); -#endif - -/* - calloc(size_t n_elements, size_t element_size); - Returns a pointer to n_elements * element_size bytes, with all locations - set to zero. -*/ -#if __STD_C -Void_t* public_cALLOc(size_t, size_t); -#else -Void_t* public_cALLOc(); -#endif - -/* - realloc(Void_t* p, size_t n) - Returns a pointer to a chunk of size n that contains the same data - as does chunk p up to the minimum of (n, p's size) bytes, or null - if no space is available. - - The returned pointer may or may not be the same as p. The algorithm - prefers extending p when possible, otherwise it employs the - equivalent of a malloc-copy-free sequence. - - If p is null, realloc is equivalent to malloc. - - If space is not available, realloc returns null, errno is set (if on - ANSI) and p is NOT freed. - - if n is for fewer bytes than already held by p, the newly unused - space is lopped off and freed if possible. Unless the #define - REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of - zero (re)allocates a minimum-sized chunk. - - Large chunks that were internally obtained via mmap will always - be reallocated using malloc-copy-free sequences unless - the system supports MREMAP (currently only linux). - - The old unix realloc convention of allowing the last-free'd chunk - to be used as an argument to realloc is not supported. -*/ -#if __STD_C -Void_t* public_rEALLOc(Void_t*, size_t); -#else -Void_t* public_rEALLOc(); -#endif - -/* - memalign(size_t alignment, size_t n); - Returns a pointer to a newly allocated chunk of n bytes, aligned - in accord with the alignment argument. - - The alignment argument should be a power of two. If the argument is - not a power of two, the nearest greater power is used. - 8-byte alignment is guaranteed by normal malloc calls, so don't - bother calling memalign with an argument of 8 or less. - - Overreliance on memalign is a sure way to fragment space. -*/ -#if __STD_C -Void_t* public_mEMALIGn(size_t, size_t); -#else -Void_t* public_mEMALIGn(); -#endif - -/* - valloc(size_t n); - Equivalent to memalign(pagesize, n), where pagesize is the page - size of the system. If the pagesize is unknown, 4096 is used. -*/ -#if __STD_C -Void_t* public_vALLOc(size_t); -#else -Void_t* public_vALLOc(); -#endif - - - -/* - mallopt(int parameter_number, int parameter_value) - Sets tunable parameters The format is to provide a - (parameter-number, parameter-value) pair. mallopt then sets the - corresponding parameter to the argument value if it can (i.e., so - long as the value is meaningful), and returns 1 if successful else - 0. SVID/XPG/ANSI defines four standard param numbers for mallopt, - normally defined in malloc.h. Only one of these (M_MXFAST) is used - in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply, - so setting them has no effect. But this malloc also supports four - other options in mallopt. See below for details. Briefly, supported - parameters are as follows (listed defaults are for "typical" - configurations). - - Symbol param # default allowed param values - M_MXFAST 1 64 0-80 (0 disables fastbins) - M_TRIM_THRESHOLD -1 256*1024 any (-1U disables trimming) - M_TOP_PAD -2 0 any - M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support) - M_MMAP_MAX -4 65536 any (0 disables use of mmap) -*/ -#if __STD_C -int public_mALLOPt(int, int); -#else -int public_mALLOPt(); -#endif - - -/* - mallinfo() - Returns (by copy) a struct containing various summary statistics: - - arena: current total non-mmapped bytes allocated from system - ordblks: the number of free chunks - smblks: the number of fastbin blocks (i.e., small chunks that - have been freed but not use resused or consolidated) - hblks: current number of mmapped regions - hblkhd: total bytes held in mmapped regions - usmblks: the maximum total allocated space. This will be greater - than current total if trimming has occurred. - fsmblks: total bytes held in fastbin blocks - uordblks: current total allocated space (normal or mmapped) - fordblks: total free space - keepcost: the maximum number of bytes that could ideally be released - back to system via malloc_trim. ("ideally" means that - it ignores page restrictions etc.) - - Because these fields are ints, but internal bookkeeping may - be kept as longs, the reported values may wrap around zero and - thus be inaccurate. -*/ -#if __STD_C -struct mallinfo public_mALLINFo(void); -#else -struct mallinfo public_mALLINFo(); -#endif - -/* - independent_calloc(size_t n_elements, size_t element_size, Void_t* chunks[]); - - independent_calloc is similar to calloc, but instead of returning a - single cleared space, it returns an array of pointers to n_elements - independent elements that can hold contents of size elem_size, each - of which starts out cleared, and can be independently freed, - realloc'ed etc. The elements are guaranteed to be adjacently - allocated (this is not guaranteed to occur with multiple callocs or - mallocs), which may also improve cache locality in some - applications. - - The "chunks" argument is optional (i.e., may be null, which is - probably the most typical usage). If it is null, the returned array - is itself dynamically allocated and should also be freed when it is - no longer needed. Otherwise, the chunks array must be of at least - n_elements in length. It is filled in with the pointers to the - chunks. - - In either case, independent_calloc returns this pointer array, or - null if the allocation failed. If n_elements is zero and "chunks" - is null, it returns a chunk representing an array with zero elements - (which should be freed if not wanted). - - Each element must be individually freed when it is no longer - needed. If you'd like to instead be able to free all at once, you - should instead use regular calloc and assign pointers into this - space to represent elements. (In this case though, you cannot - independently free elements.) - - independent_calloc simplifies and speeds up implementations of many - kinds of pools. It may also be useful when constructing large data - structures that initially have a fixed number of fixed-sized nodes, - but the number is not known at compile time, and some of the nodes - may later need to be freed. For example: - - struct Node { int item; struct Node* next; }; - - struct Node* build_list() { - struct Node** pool; - int n = read_number_of_nodes_needed(); - if (n <= 0) return 0; - pool = (struct Node**)(independent_calloc(n, sizeof(struct Node), 0); - if (pool == 0) die(); - // organize into a linked list... - struct Node* first = pool[0]; - for (i = 0; i < n-1; ++i) - pool[i]->next = pool[i+1]; - free(pool); // Can now free the array (or not, if it is needed later) - return first; - } -*/ -#if __STD_C -Void_t** public_iCALLOc(size_t, size_t, Void_t**); -#else -Void_t** public_iCALLOc(); -#endif - -/* - independent_comalloc(size_t n_elements, size_t sizes[], Void_t* chunks[]); - - independent_comalloc allocates, all at once, a set of n_elements - chunks with sizes indicated in the "sizes" array. It returns - an array of pointers to these elements, each of which can be - independently freed, realloc'ed etc. The elements are guaranteed to - be adjacently allocated (this is not guaranteed to occur with - multiple callocs or mallocs), which may also improve cache locality - in some applications. - - The "chunks" argument is optional (i.e., may be null). If it is null - the returned array is itself dynamically allocated and should also - be freed when it is no longer needed. Otherwise, the chunks array - must be of at least n_elements in length. It is filled in with the - pointers to the chunks. - - In either case, independent_comalloc returns this pointer array, or - null if the allocation failed. If n_elements is zero and chunks is - null, it returns a chunk representing an array with zero elements - (which should be freed if not wanted). - - Each element must be individually freed when it is no longer - needed. If you'd like to instead be able to free all at once, you - should instead use a single regular malloc, and assign pointers at - particular offsets in the aggregate space. (In this case though, you - cannot independently free elements.) - - independent_comallac differs from independent_calloc in that each - element may have a different size, and also that it does not - automatically clear elements. - - independent_comalloc can be used to speed up allocation in cases - where several structs or objects must always be allocated at the - same time. For example: - - struct Head { ... } - struct Foot { ... } - - void send_message(char* msg) { - int msglen = strlen(msg); - size_t sizes[3] = { sizeof(struct Head), msglen, sizeof(struct Foot) }; - void* chunks[3]; - if (independent_comalloc(3, sizes, chunks) == 0) - die(); - struct Head* head = (struct Head*)(chunks[0]); - char* body = (char*)(chunks[1]); - struct Foot* foot = (struct Foot*)(chunks[2]); - // ... - } - - In general though, independent_comalloc is worth using only for - larger values of n_elements. For small values, you probably won't - detect enough difference from series of malloc calls to bother. - - Overuse of independent_comalloc can increase overall memory usage, - since it cannot reuse existing noncontiguous small chunks that - might be available for some of the elements. -*/ -#if __STD_C -Void_t** public_iCOMALLOc(size_t, size_t*, Void_t**); -#else -Void_t** public_iCOMALLOc(); -#endif - - -/* - pvalloc(size_t n); - Equivalent to valloc(minimum-page-that-holds(n)), that is, - round up n to nearest pagesize. - */ -#if __STD_C -Void_t* public_pVALLOc(size_t); -#else -Void_t* public_pVALLOc(); -#endif - -/* - cfree(Void_t* p); - Equivalent to free(p). - - cfree is needed/defined on some systems that pair it with calloc, - for odd historical reasons (such as: cfree is used in example - code in the first edition of K&R). -*/ -#if __STD_C -void public_cFREe(Void_t*); -#else -void public_cFREe(); -#endif - -/* - malloc_trim(size_t pad); - - If possible, gives memory back to the system (via negative - arguments to sbrk) if there is unused memory at the `high' end of - the malloc pool. You can call this after freeing large blocks of - memory to potentially reduce the system-level memory requirements - of a program. However, it cannot guarantee to reduce memory. Under - some allocation patterns, some large free blocks of memory will be - locked between two used chunks, so they cannot be given back to - the system. - - The `pad' argument to malloc_trim represents the amount of free - trailing space to leave untrimmed. If this argument is zero, - only the minimum amount of memory to maintain internal data - structures will be left (one page or less). Non-zero arguments - can be supplied to maintain enough trailing space to service - future expected allocations without having to re-obtain memory - from the system. - - Malloc_trim returns 1 if it actually released any memory, else 0. - On systems that do not support "negative sbrks", it will always - rreturn 0. -*/ -#if __STD_C -int public_mTRIm(size_t); -#else -int public_mTRIm(); -#endif - -/* - malloc_usable_size(Void_t* p); - - Returns the number of bytes you can actually use in - an allocated chunk, which may be more than you requested (although - often not) due to alignment and minimum size constraints. - You can use this many bytes without worrying about - overwriting other allocated objects. This is not a particularly great - programming practice. malloc_usable_size can be more useful in - debugging and assertions, for example: - - p = malloc(n); - assert(malloc_usable_size(p) >= 256); - -*/ -#if __STD_C -size_t public_mUSABLe(Void_t*); -#else -size_t public_mUSABLe(); -#endif - -/* - malloc_stats(); - Prints on stderr the amount of space obtained from the system (both - via sbrk and mmap), the maximum amount (which may be more than - current if malloc_trim and/or munmap got called), and the current - number of bytes allocated via malloc (or realloc, etc) but not yet - freed. Note that this is the number of bytes allocated, not the - number requested. It will be larger than the number requested - because of alignment and bookkeeping overhead. Because it includes - alignment wastage as being in use, this figure may be greater than - zero even when no user-level chunks are allocated. - - The reported current and maximum system memory can be inaccurate if - a program makes other calls to system memory allocation functions - (normally sbrk) outside of malloc. - - malloc_stats prints only the most commonly interesting statistics. - More information can be obtained by calling mallinfo. - -*/ -#if __STD_C -void public_mSTATs(); -#else -void public_mSTATs(); -#endif - -/* mallopt tuning options */ - -/* - M_MXFAST is the maximum request size used for "fastbins", special bins - that hold returned chunks without consolidating their spaces. This - enables future requests for chunks of the same size to be handled - very quickly, but can increase fragmentation, and thus increase the - overall memory footprint of a program. - - This malloc manages fastbins very conservatively yet still - efficiently, so fragmentation is rarely a problem for values less - than or equal to the default. The maximum supported value of MXFAST - is 80. You wouldn't want it any higher than this anyway. Fastbins - are designed especially for use with many small structs, objects or - strings -- the default handles structs/objects/arrays with sizes up - to 16 4byte fields, or small strings representing words, tokens, - etc. Using fastbins for larger objects normally worsens - fragmentation without improving speed. - - M_MXFAST is set in REQUEST size units. It is internally used in - chunksize units, which adds padding and alignment. You can reduce - M_MXFAST to 0 to disable all use of fastbins. This causes the malloc - algorithm to be a closer approximation of fifo-best-fit in all cases, - not just for larger requests, but will generally cause it to be - slower. -*/ - - -/* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */ -#ifndef M_MXFAST -#define M_MXFAST 1 -#endif - -#ifndef DEFAULT_MXFAST -#define DEFAULT_MXFAST 64 -#endif - - -/* - M_TRIM_THRESHOLD is the maximum amount of unused top-most memory - to keep before releasing via malloc_trim in free(). - - Automatic trimming is mainly useful in long-lived programs. - Because trimming via sbrk can be slow on some systems, and can - sometimes be wasteful (in cases where programs immediately - afterward allocate more large chunks) the value should be high - enough so that your overall system performance would improve by - releasing this much memory. - - The trim threshold and the mmap control parameters (see below) - can be traded off with one another. Trimming and mmapping are - two different ways of releasing unused memory back to the - system. Between these two, it is often possible to keep - system-level demands of a long-lived program down to a bare - minimum. For example, in one test suite of sessions measuring - the XF86 X server on Linux, using a trim threshold of 128K and a - mmap threshold of 192K led to near-minimal long term resource - consumption. - - If you are using this malloc in a long-lived program, it should - pay to experiment with these values. As a rough guide, you - might set to a value close to the average size of a process - (program) running on your system. Releasing this much memory - would allow such a process to run in memory. Generally, it's - worth it to tune for trimming rather tham memory mapping when a - program undergoes phases where several large chunks are - allocated and released in ways that can reuse each other's - storage, perhaps mixed with phases where there are no such - chunks at all. And in well-behaved long-lived programs, - controlling release of large blocks via trimming versus mapping - is usually faster. - - However, in most programs, these parameters serve mainly as - protection against the system-level effects of carrying around - massive amounts of unneeded memory. Since frequent calls to - sbrk, mmap, and munmap otherwise degrade performance, the default - parameters are set to relatively high values that serve only as - safeguards. - - The trim value must be greater than page size to have any useful - effect. To disable trimming completely, you can set to - (unsigned long)(-1) - - Trim settings interact with fastbin (MXFAST) settings: Unless - TRIM_FASTBINS is defined, automatic trimming never takes place upon - freeing a chunk with size less than or equal to MXFAST. Trimming is - instead delayed until subsequent freeing of larger chunks. However, - you can still force an attempted trim by calling malloc_trim. - - Also, trimming is not generally possible in cases where - the main arena is obtained via mmap. - - Note that the trick some people use of mallocing a huge space and - then freeing it at program startup, in an attempt to reserve system - memory, doesn't have the intended effect under automatic trimming, - since that memory will immediately be returned to the system. -*/ - -#define M_TRIM_THRESHOLD -1 - -#ifndef DEFAULT_TRIM_THRESHOLD -#define DEFAULT_TRIM_THRESHOLD (256 * 1024) -#endif - -/* - M_TOP_PAD is the amount of extra `padding' space to allocate or - retain whenever sbrk is called. It is used in two ways internally: - - * When sbrk is called to extend the top of the arena to satisfy - a new malloc request, this much padding is added to the sbrk - request. - - * When malloc_trim is called automatically from free(), - it is used as the `pad' argument. - - In both cases, the actual amount of padding is rounded - so that the end of the arena is always a system page boundary. - - The main reason for using padding is to avoid calling sbrk so - often. Having even a small pad greatly reduces the likelihood - that nearly every malloc request during program start-up (or - after trimming) will invoke sbrk, which needlessly wastes - time. - - Automatic rounding-up to page-size units is normally sufficient - to avoid measurable overhead, so the default is 0. However, in - systems where sbrk is relatively slow, it can pay to increase - this value, at the expense of carrying around more memory than - the program needs. -*/ - -#define M_TOP_PAD -2 - -#ifndef DEFAULT_TOP_PAD -#define DEFAULT_TOP_PAD (0) -#endif - -/* - M_MMAP_THRESHOLD is the request size threshold for using mmap() - to service a request. Requests of at least this size that cannot - be allocated using already-existing space will be serviced via mmap. - (If enough normal freed space already exists it is used instead.) - - Using mmap segregates relatively large chunks of memory so that - they can be individually obtained and released from the host - system. A request serviced through mmap is never reused by any - other request (at least not directly; the system may just so - happen to remap successive requests to the same locations). - - Segregating space in this way has the benefits that: - - 1. Mmapped space can ALWAYS be individually released back - to the system, which helps keep the system level memory - demands of a long-lived program low. - 2. Mapped memory can never become `locked' between - other chunks, as can happen with normally allocated chunks, which - means that even trimming via malloc_trim would not release them. - 3. On some systems with "holes" in address spaces, mmap can obtain - memory that sbrk cannot. - - However, it has the disadvantages that: - - 1. The space cannot be reclaimed, consolidated, and then - used to service later requests, as happens with normal chunks. - 2. It can lead to more wastage because of mmap page alignment - requirements - 3. It causes malloc performance to be more dependent on host - system memory management support routines which may vary in - implementation quality and may impose arbitrary - limitations. Generally, servicing a request via normal - malloc steps is faster than going through a system's mmap. - - The advantages of mmap nearly always outweigh disadvantages for - "large" chunks, but the value of "large" varies across systems. The - default is an empirically derived value that works well in most - systems. -*/ - -#define M_MMAP_THRESHOLD -3 - -#ifndef DEFAULT_MMAP_THRESHOLD -#define DEFAULT_MMAP_THRESHOLD (256 * 1024) -#endif - -/* - M_MMAP_MAX is the maximum number of requests to simultaneously - service using mmap. This parameter exists because -. Some systems have a limited number of internal tables for - use by mmap, and using more than a few of them may degrade - performance. - - The default is set to a value that serves only as a safeguard. - Setting to 0 disables use of mmap for servicing large requests. If - HAVE_MMAP is not set, the default value is 0, and attempts to set it - to non-zero values in mallopt will fail. -*/ - -#define M_MMAP_MAX -4 - -#ifndef DEFAULT_MMAP_MAX -#if HAVE_MMAP -#define DEFAULT_MMAP_MAX (65536) -#else -#define DEFAULT_MMAP_MAX (0) -#endif -#endif - -#ifdef __cplusplus -}; /* end of extern "C" */ -#endif - - -/* RN XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ -#endif - -/* - ======================================================================== - To make a fully customizable malloc.h header file, cut everything - above this line, put into file malloc.h, edit to suit, and #include it - on the next line, as well as in programs that use this malloc. - ======================================================================== -*/ - -/* #include "malloc.h" */ - -/* --------------------- public wrappers ---------------------- */ - -#ifdef USE_PUBLIC_MALLOC_WRAPPERS - -/* Declare all routines as internal */ -#if __STD_C -static Void_t* mALLOc(size_t); -static void fREe(Void_t*); -static Void_t* rEALLOc(Void_t*, size_t); -static Void_t* mEMALIGn(size_t, size_t); -static Void_t* vALLOc(size_t); -static Void_t* pVALLOc(size_t); -static Void_t* cALLOc(size_t, size_t); -static Void_t** iCALLOc(size_t, size_t, Void_t**); -static Void_t** iCOMALLOc(size_t, size_t*, Void_t**); -static void cFREe(Void_t*); -static int mTRIm(size_t); -static size_t mUSABLe(Void_t*); -static void mSTATs(); -static int mALLOPt(int, int); -static struct mallinfo mALLINFo(void); -#else -static Void_t* mALLOc(); -static void fREe(); -static Void_t* rEALLOc(); -static Void_t* mEMALIGn(); -static Void_t* vALLOc(); -static Void_t* pVALLOc(); -static Void_t* cALLOc(); -static Void_t** iCALLOc(); -static Void_t** iCOMALLOc(); -static void cFREe(); -static int mTRIm(); -static size_t mUSABLe(); -static void mSTATs(); -static int mALLOPt(); -static struct mallinfo mALLINFo(); -#endif - -/* - MALLOC_PREACTION and MALLOC_POSTACTION should be - defined to return 0 on success, and nonzero on failure. - The return value of MALLOC_POSTACTION is currently ignored - in wrapper functions since there is no reasonable default - action to take on failure. -*/ - - -#ifdef USE_MALLOC_LOCK - -#ifdef WIN32 - -static int mALLOC_MUTEx; -#define MALLOC_PREACTION slwait(&mALLOC_MUTEx) -#define MALLOC_POSTACTION slrelease(&mALLOC_MUTEx) - -#else - -#include <pthread.h> - -static pthread_mutex_t mALLOC_MUTEx = PTHREAD_MUTEX_INITIALIZER; - -#define MALLOC_PREACTION pthread_mutex_lock(&mALLOC_MUTEx) -#define MALLOC_POSTACTION pthread_mutex_unlock(&mALLOC_MUTEx) - -#endif /* USE_MALLOC_LOCK */ - -#else - -/* Substitute anything you like for these */ - -#define MALLOC_PREACTION (0) -#define MALLOC_POSTACTION (0) - -#endif - -Void_t* public_mALLOc(size_t bytes) { - Void_t* m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = mALLOc(bytes); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -void public_fREe(Void_t* m) { - if (MALLOC_PREACTION != 0) { - return; - } - fREe(m); - if (MALLOC_POSTACTION != 0) { - } -} - -Void_t* public_rEALLOc(Void_t* m, size_t bytes) { - if (MALLOC_PREACTION != 0) { - return 0; - } - m = rEALLOc(m, bytes); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -Void_t* public_mEMALIGn(size_t alignment, size_t bytes) { - Void_t* m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = mEMALIGn(alignment, bytes); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -Void_t* public_vALLOc(size_t bytes) { - Void_t* m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = vALLOc(bytes); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -Void_t* public_pVALLOc(size_t bytes) { - Void_t* m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = pVALLOc(bytes); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -Void_t* public_cALLOc(size_t n, size_t elem_size) { - Void_t* m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = cALLOc(n, elem_size); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - - -Void_t** public_iCALLOc(size_t n, size_t elem_size, Void_t** chunks) { - Void_t** m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = iCALLOc(n, elem_size, chunks); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -Void_t** public_iCOMALLOc(size_t n, size_t sizes[], Void_t** chunks) { - Void_t** m; - if (MALLOC_PREACTION != 0) { - return 0; - } - m = iCOMALLOc(n, sizes, chunks); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -void public_cFREe(Void_t* m) { - if (MALLOC_PREACTION != 0) { - return; - } - cFREe(m); - if (MALLOC_POSTACTION != 0) { - } -} - -int public_mTRIm(size_t s) { - int result; - if (MALLOC_PREACTION != 0) { - return 0; - } - result = mTRIm(s); - if (MALLOC_POSTACTION != 0) { - } - return result; -} - -size_t public_mUSABLe(Void_t* m) { - size_t result; - if (MALLOC_PREACTION != 0) { - return 0; - } - result = mUSABLe(m); - if (MALLOC_POSTACTION != 0) { - } - return result; -} - -void public_mSTATs() { - if (MALLOC_PREACTION != 0) { - return; - } - mSTATs(); - if (MALLOC_POSTACTION != 0) { - } -} - -struct mallinfo public_mALLINFo() { - struct mallinfo m; - if (MALLOC_PREACTION != 0) { - struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; - return nm; - } - m = mALLINFo(); - if (MALLOC_POSTACTION != 0) { - } - return m; -} - -int public_mALLOPt(int p, int v) { - int result; - if (MALLOC_PREACTION != 0) { - return 0; - } - result = mALLOPt(p, v); - if (MALLOC_POSTACTION != 0) { - } - return result; -} - -#endif - - - -/* ------------- Optional versions of memcopy ---------------- */ - - -#if USE_MEMCPY - -/* - Note: memcpy is ONLY invoked with non-overlapping regions, - so the (usually slower) memmove is not needed. -*/ - -#define MALLOC_COPY(dest, src, nbytes) memcpy(dest, src, nbytes) -#define MALLOC_ZERO(dest, nbytes) memset(dest, 0, nbytes) - -#else /* !USE_MEMCPY */ - -/* Use Duff's device for good zeroing/copying performance. */ - -#define MALLOC_ZERO(charp, nbytes) \ -do { \ - INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \ - CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \ - long mcn; \ - if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ - switch (mctmp) { \ - case 0: for(;;) { *mzp++ = 0; \ - case 7: *mzp++ = 0; \ - case 6: *mzp++ = 0; \ - case 5: *mzp++ = 0; \ - case 4: *mzp++ = 0; \ - case 3: *mzp++ = 0; \ - case 2: *mzp++ = 0; \ - case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \ - } \ -} while(0) - -#define MALLOC_COPY(dest,src,nbytes) \ -do { \ - INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ - INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ - CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \ - long mcn; \ - if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \ - switch (mctmp) { \ - case 0: for(;;) { *mcdst++ = *mcsrc++; \ - case 7: *mcdst++ = *mcsrc++; \ - case 6: *mcdst++ = *mcsrc++; \ - case 5: *mcdst++ = *mcsrc++; \ - case 4: *mcdst++ = *mcsrc++; \ - case 3: *mcdst++ = *mcsrc++; \ - case 2: *mcdst++ = *mcsrc++; \ - case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \ - } \ -} while(0) - -#endif - -/* ------------------ MMAP support ------------------ */ - - -#if HAVE_MMAP - -#ifndef LACKS_FCNTL_H -#include <fcntl.h> -#endif - -#ifndef LACKS_SYS_MMAN_H -#include <sys/mman.h> -#endif - -#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) -#define MAP_ANONYMOUS MAP_ANON -#endif - -/* - Nearly all versions of mmap support MAP_ANONYMOUS, - so the following is unlikely to be needed, but is - supplied just in case. -*/ - -#ifndef MAP_ANONYMOUS - -static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */ - -#define MMAP(addr, size, prot, flags) ((dev_zero_fd < 0) ? \ - (dev_zero_fd = open("/dev/zero", O_RDWR), \ - mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) : \ - mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) - -#else - -#define MMAP(addr, size, prot, flags) \ - (mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0)) - -#endif - - -#endif /* HAVE_MMAP */ - - -/* - ----------------------- Chunk representations ----------------------- -*/ - - -/* - This struct declaration is misleading (but accurate and necessary). - It declares a "view" into memory allowing access to necessary - fields at known offsets from a given base. See explanation below. -*/ - -struct malloc_chunk { - - INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */ - INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */ - - struct malloc_chunk* fd; /* double links -- used only if free. */ - struct malloc_chunk* bk; -}; - - -typedef struct malloc_chunk* mchunkptr; - -/* - malloc_chunk details: - - (The following includes lightly edited explanations by Colin Plumb.) - - Chunks of memory are maintained using a `boundary tag' method as - described in e.g., Knuth or Standish. (See the paper by Paul - Wilson ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a - survey of such techniques.) Sizes of free chunks are stored both - in the front of each chunk and at the end. This makes - consolidating fragmented chunks into bigger chunks very fast. The - size fields also hold bits representing whether chunks are free or - in use. - - An allocated chunk looks like this: - - - chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous chunk, if allocated | | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk, in bytes |P| - mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | User data starts here... . - . . - . (malloc_usable_space() bytes) . - . | -nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of chunk | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - - Where "chunk" is the front of the chunk for the purpose of most of - the malloc code, but "mem" is the pointer that is returned to the - user. "Nextchunk" is the beginning of the next contiguous chunk. - - Chunks always begin on even word boundries, so the mem portion - (which is returned to the user) is also on an even word boundary, and - thus at least double-word aligned. - - Free chunks are stored in circular doubly-linked lists, and look like this: - - chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Size of previous chunk | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - `head:' | Size of chunk, in bytes |P| - mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Forward pointer to next chunk in list | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Back pointer to previous chunk in list | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Unused space (may be 0 bytes long) . - . . - . | -nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - `foot:' | Size of chunk, in bytes | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - The P (PREV_INUSE) bit, stored in the unused low-order bit of the - chunk size (which is always a multiple of two words), is an in-use - bit for the *previous* chunk. If that bit is *clear*, then the - word before the current chunk size contains the previous chunk - size, and can be used to find the front of the previous chunk. - The very first chunk allocated always has this bit set, - preventing access to non-existent (or non-owned) memory. If - prev_inuse is set for any given chunk, then you CANNOT determine - the size of the previous chunk, and might even get a memory - addressing fault when trying to do so. - - Note that the `foot' of the current chunk is actually represented - as the prev_size of the NEXT chunk. This makes it easier to - deal with alignments etc but can be very confusing when trying - to extend or adapt this code. - - The two exceptions to all this are - - 1. The special chunk `top' doesn't bother using the - trailing size field since there is no next contiguous chunk - that would have to index off it. After initialization, `top' - is forced to always exist. If it would become less than - MINSIZE bytes long, it is replenished. - - 2. Chunks allocated via mmap, which have the second-lowest-order - bit (IS_MMAPPED) set in their size fields. Because they are - allocated one-by-one, each must contain its own trailing size field. - -*/ - -/* - ---------- Size and alignment checks and conversions ---------- -*/ - -/* conversion from malloc headers to user pointers, and back */ - -#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ)) -#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ)) - -/* The smallest possible chunk */ -#define MIN_CHUNK_SIZE (sizeof(struct malloc_chunk)) - -/* The smallest size we can malloc is an aligned minimal chunk */ - -#define MINSIZE \ - (CHUNK_SIZE_T)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)) - -/* Check if m has acceptable alignment */ - -#define aligned_OK(m) (((PTR_UINT)((m)) & (MALLOC_ALIGN_MASK)) == 0) - - -/* - Check if a request is so large that it would wrap around zero when - padded and aligned. To simplify some other code, the bound is made - low enough so that adding MINSIZE will also not wrap around sero. -*/ - -#define REQUEST_OUT_OF_RANGE(req) \ - ((CHUNK_SIZE_T)(req) >= \ - (CHUNK_SIZE_T)(INTERNAL_SIZE_T)(-2 * MINSIZE)) - -/* pad request bytes into a usable size -- internal version */ - -#define request2size(req) \ - (((req) + SIZE_SZ + MALLOC_ALIGN_MASK < MINSIZE) ? \ - MINSIZE : \ - ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK) - -/* Same, except also perform argument check */ - -#define checked_request2size(req, sz) \ - if (REQUEST_OUT_OF_RANGE(req)) { \ - MALLOC_FAILURE_ACTION; \ - return 0; \ - } \ - (sz) = request2size(req); - -/* - --------------- Physical chunk operations --------------- -*/ - - -/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */ -#define PREV_INUSE 0x1 - -/* extract inuse bit of previous chunk */ -#define prev_inuse(p) ((p)->size & PREV_INUSE) - - -/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */ -#define IS_MMAPPED 0x2 - -/* check for mmap()'ed chunk */ -#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED) - -/* - Bits to mask off when extracting size - - Note: IS_MMAPPED is intentionally not masked off from size field in - macros for which mmapped chunks should never be seen. This should - cause helpful core dumps to occur if it is tried by accident by - people extending or adapting this malloc. -*/ -#define SIZE_BITS (PREV_INUSE|IS_MMAPPED) - -/* Get size, ignoring use bits */ -#define chunksize(p) ((p)->size & ~(SIZE_BITS)) - - -/* Ptr to next physical malloc_chunk. */ -#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) )) - -/* Ptr to previous physical malloc_chunk */ -#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) )) - -/* Treat space at ptr + offset as a chunk */ -#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) - -/* extract p's inuse bit */ -#define inuse(p)\ -((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE) - -/* set/clear chunk as being inuse without otherwise disturbing */ -#define set_inuse(p)\ -((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE - -#define clear_inuse(p)\ -((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE) - - -/* check/set/clear inuse bits in known places */ -#define inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE) - -#define set_inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE) - -#define clear_inuse_bit_at_offset(p, s)\ - (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE)) - - -/* Set size at head, without disturbing its use bit */ -#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s))) - -/* Set size/use field */ -#define set_head(p, s) ((p)->size = (s)) - -/* Set size at footer (only when chunk is not in use) */ -#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s)) - - -/* - -------------------- Internal data structures -------------------- - - All internal state is held in an instance of malloc_state defined - below. There are no other static variables, except in two optional - cases: - * If USE_MALLOC_LOCK is defined, the mALLOC_MUTEx declared above. - * If HAVE_MMAP is true, but mmap doesn't support - MAP_ANONYMOUS, a dummy file descriptor for mmap. - - Beware of lots of tricks that minimize the total bookkeeping space - requirements. The result is a little over 1K bytes (for 4byte - pointers and size_t.) -*/ - -/* - Bins - - An array of bin headers for free chunks. Each bin is doubly - linked. The bins are approximately proportionally (log) spaced. - There are a lot of these bins (128). This may look excessive, but - works very well in practice. Most bins hold sizes that are - unusual as malloc request sizes, but are more usual for fragments - and consolidated sets of chunks, which is what these bins hold, so - they can be found quickly. All procedures maintain the invariant - that no consolidated chunk physically borders another one, so each - chunk in a list is known to be preceeded and followed by either - inuse chunks or the ends of memory. - - Chunks in bins are kept in size order, with ties going to the - approximately least recently used chunk. Ordering isn't needed - for the small bins, which all contain the same-sized chunks, but - facilitates best-fit allocation for larger chunks. These lists - are just sequential. Keeping them in order almost never requires - enough traversal to warrant using fancier ordered data - structures. - - Chunks of the same size are linked with the most - recently freed at the front, and allocations are taken from the - back. This results in LRU (FIFO) allocation order, which tends - to give each chunk an equal opportunity to be consolidated with - adjacent freed chunks, resulting in larger free chunks and less - fragmentation. - - To simplify use in double-linked lists, each bin header acts - as a malloc_chunk. This avoids special-casing for headers. - But to conserve space and improve locality, we allocate - only the fd/bk pointers of bins, and then use repositioning tricks - to treat these as the fields of a malloc_chunk*. -*/ - -typedef struct malloc_chunk* mbinptr; - -/* addressing -- note that bin_at(0) does not exist */ -#define bin_at(m, i) ((mbinptr)((char*)&((m)->bins[(i)<<1]) - (SIZE_SZ<<1))) - -/* analog of ++bin */ -#define next_bin(b) ((mbinptr)((char*)(b) + (sizeof(mchunkptr)<<1))) - -/* Reminders about list directionality within bins */ -#define first(b) ((b)->fd) -#define last(b) ((b)->bk) - -/* Take a chunk off a bin list */ -#define unlink(P, BK, FD) { \ - FD = P->fd; \ - BK = P->bk; \ - FD->bk = BK; \ - BK->fd = FD; \ -} - -/* - Indexing - - Bins for sizes < 512 bytes contain chunks of all the same size, spaced - 8 bytes apart. Larger bins are approximately logarithmically spaced: - - 64 bins of size 8 - 32 bins of size 64 - 16 bins of size 512 - 8 bins of size 4096 - 4 bins of size 32768 - 2 bins of size 262144 - 1 bin of size what's left - - The bins top out around 1MB because we expect to service large - requests via mmap. -*/ - -#define NBINS 96 -#define NSMALLBINS 32 -#define SMALLBIN_WIDTH 8 -#define MIN_LARGE_SIZE 256 - -#define in_smallbin_range(sz) \ - ((CHUNK_SIZE_T)(sz) < (CHUNK_SIZE_T)MIN_LARGE_SIZE) - -#define smallbin_index(sz) (((unsigned)(sz)) >> 3) - -/* - Compute index for size. We expect this to be inlined when - compiled with optimization, else not, which works out well. -*/ -static int largebin_index(unsigned int sz) { - unsigned int x = sz >> SMALLBIN_WIDTH; - unsigned int m; /* bit position of highest set bit of m */ - - if (x >= 0x10000) return NBINS-1; - - /* On intel, use BSRL instruction to find highest bit */ -#if defined(__GNUC__) && defined(i386) - - __asm__("bsrl %1,%0\n\t" - : "=r" (m) - : "g" (x)); - -#else - { - /* - Based on branch-free nlz algorithm in chapter 5 of Henry - S. Warren Jr's book "Hacker's Delight". - */ - - unsigned int n = ((x - 0x100) >> 16) & 8; - x <<= n; - m = ((x - 0x1000) >> 16) & 4; - n += m; - x <<= m; - m = ((x - 0x4000) >> 16) & 2; - n += m; - x = (x << m) >> 14; - m = 13 - n + (x & ~(x>>1)); - } -#endif - - /* Use next 2 bits to create finer-granularity bins */ - return NSMALLBINS + (m << 2) + ((sz >> (m + 6)) & 3); -} - -#define bin_index(sz) \ - ((in_smallbin_range(sz)) ? smallbin_index(sz) : largebin_index(sz)) - -/* - FIRST_SORTED_BIN_SIZE is the chunk size corresponding to the - first bin that is maintained in sorted order. This must - be the smallest size corresponding to a given bin. - - Normally, this should be MIN_LARGE_SIZE. But you can weaken - best fit guarantees to sometimes speed up malloc by increasing value. - Doing this means that malloc may choose a chunk that is - non-best-fitting by up to the width of the bin. - - Some useful cutoff values: - 512 - all bins sorted - 2560 - leaves bins <= 64 bytes wide unsorted - 12288 - leaves bins <= 512 bytes wide unsorted - 65536 - leaves bins <= 4096 bytes wide unsorted - 262144 - leaves bins <= 32768 bytes wide unsorted - -1 - no bins sorted (not recommended!) -*/ - -#define FIRST_SORTED_BIN_SIZE MIN_LARGE_SIZE -/* #define FIRST_SORTED_BIN_SIZE 65536 */ - -/* - Unsorted chunks - - All remainders from chunk splits, as well as all returned chunks, - are first placed in the "unsorted" bin. They are then placed - in regular bins after malloc gives them ONE chance to be used before - binning. So, basically, the unsorted_chunks list acts as a queue, - with chunks being placed on it in free (and malloc_consolidate), - and taken off (to be either used or placed in bins) in malloc. -*/ - -/* The otherwise unindexable 1-bin is used to hold unsorted chunks. */ -#define unsorted_chunks(M) (bin_at(M, 1)) - -/* - Top - - The top-most available chunk (i.e., the one bordering the end of - available memory) is treated specially. It is never included in - any bin, is used only if no other chunk is available, and is - released back to the system if it is very large (see - M_TRIM_THRESHOLD). Because top initially - points to its own bin with initial zero size, thus forcing - extension on the first malloc request, we avoid having any special - code in malloc to check whether it even exists yet. But we still - need to do so when getting memory from system, so we make - initial_top treat the bin as a legal but unusable chunk during the - interval between initialization and the first call to - sYSMALLOc. (This is somewhat delicate, since it relies on - the 2 preceding words to be zero during this interval as well.) -*/ - -/* Conveniently, the unsorted bin can be used as dummy top on first call */ -#define initial_top(M) (unsorted_chunks(M)) - -/* - Binmap - - To help compensate for the large number of bins, a one-level index - structure is used for bin-by-bin searching. `binmap' is a - bitvector recording whether bins are definitely empty so they can - be skipped over during during traversals. The bits are NOT always - cleared as soon as bins are empty, but instead only - when they are noticed to be empty during traversal in malloc. -*/ - -/* Conservatively use 32 bits per map word, even if on 64bit system */ -#define BINMAPSHIFT 5 -#define BITSPERMAP (1U << BINMAPSHIFT) -#define BINMAPSIZE (NBINS / BITSPERMAP) - -#define idx2block(i) ((i) >> BINMAPSHIFT) -#define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT)-1)))) - -#define mark_bin(m,i) ((m)->binmap[idx2block(i)] |= idx2bit(i)) -#define unmark_bin(m,i) ((m)->binmap[idx2block(i)] &= ~(idx2bit(i))) -#define get_binmap(m,i) ((m)->binmap[idx2block(i)] & idx2bit(i)) - -/* - Fastbins - - An array of lists holding recently freed small chunks. Fastbins - are not doubly linked. It is faster to single-link them, and - since chunks are never removed from the middles of these lists, - double linking is not necessary. Also, unlike regular bins, they - are not even processed in FIFO order (they use faster LIFO) since - ordering doesn't much matter in the transient contexts in which - fastbins are normally used. - - Chunks in fastbins keep their inuse bit set, so they cannot - be consolidated with other free chunks. malloc_consolidate - releases all chunks in fastbins and consolidates them with - other free chunks. -*/ - -typedef struct malloc_chunk* mfastbinptr; - -/* offset 2 to use otherwise unindexable first 2 bins */ -#define fastbin_index(sz) ((((unsigned int)(sz)) >> 3) - 2) - -/* The maximum fastbin request size we support */ -#define MAX_FAST_SIZE 80 - -#define NFASTBINS (fastbin_index(request2size(MAX_FAST_SIZE))+1) - -/* - FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free() - that triggers automatic consolidation of possibly-surrounding - fastbin chunks. This is a heuristic, so the exact value should not - matter too much. It is defined at half the default trim threshold as a - compromise heuristic to only attempt consolidation if it is likely - to lead to trimming. However, it is not dynamically tunable, since - consolidation reduces fragmentation surrounding loarge chunks even - if trimming is not used. -*/ - -#define FASTBIN_CONSOLIDATION_THRESHOLD \ - ((unsigned long)(DEFAULT_TRIM_THRESHOLD) >> 1) - -/* - Since the lowest 2 bits in max_fast don't matter in size comparisons, - they are used as flags. -*/ - -/* - ANYCHUNKS_BIT held in max_fast indicates that there may be any - freed chunks at all. It is set true when entering a chunk into any - bin. -*/ - -#define ANYCHUNKS_BIT (1U) - -#define have_anychunks(M) (((M)->max_fast & ANYCHUNKS_BIT)) -#define set_anychunks(M) ((M)->max_fast |= ANYCHUNKS_BIT) -#define clear_anychunks(M) ((M)->max_fast &= ~ANYCHUNKS_BIT) - -/* - FASTCHUNKS_BIT held in max_fast indicates that there are probably - some fastbin chunks. It is set true on entering a chunk into any - fastbin, and cleared only in malloc_consolidate. -*/ - -#define FASTCHUNKS_BIT (2U) - -#define have_fastchunks(M) (((M)->max_fast & FASTCHUNKS_BIT)) -#define set_fastchunks(M) ((M)->max_fast |= (FASTCHUNKS_BIT|ANYCHUNKS_BIT)) -#define clear_fastchunks(M) ((M)->max_fast &= ~(FASTCHUNKS_BIT)) - -/* - Set value of max_fast. - Use impossibly small value if 0. -*/ - -#define set_max_fast(M, s) \ - (M)->max_fast = (((s) == 0)? SMALLBIN_WIDTH: request2size(s)) | \ - ((M)->max_fast & (FASTCHUNKS_BIT|ANYCHUNKS_BIT)) - -#define get_max_fast(M) \ - ((M)->max_fast & ~(FASTCHUNKS_BIT | ANYCHUNKS_BIT)) - - -/* - morecore_properties is a status word holding dynamically discovered - or controlled properties of the morecore function -*/ - -#define MORECORE_CONTIGUOUS_BIT (1U) - -#define contiguous(M) \ - (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT)) -#define noncontiguous(M) \ - (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT) == 0) -#define set_contiguous(M) \ - ((M)->morecore_properties |= MORECORE_CONTIGUOUS_BIT) -#define set_noncontiguous(M) \ - ((M)->morecore_properties &= ~MORECORE_CONTIGUOUS_BIT) - - -/* - ----------- Internal state representation and initialization ----------- -*/ - -struct malloc_state { - - /* The maximum chunk size to be eligible for fastbin */ - INTERNAL_SIZE_T max_fast; /* low 2 bits used as flags */ - - /* Fastbins */ - mfastbinptr fastbins[NFASTBINS]; - - /* Base of the topmost chunk -- not otherwise kept in a bin */ - mchunkptr top; - - /* The remainder from the most recent split of a small request */ - mchunkptr last_remainder; - - /* Normal bins packed as described above */ - mchunkptr bins[NBINS * 2]; - - /* Bitmap of bins. Trailing zero map handles cases of largest binned size */ - unsigned int binmap[BINMAPSIZE+1]; - - /* Tunable parameters */ - CHUNK_SIZE_T trim_threshold; - INTERNAL_SIZE_T top_pad; - INTERNAL_SIZE_T mmap_threshold; - - /* Memory map support */ - int n_mmaps; - int n_mmaps_max; - int max_n_mmaps; - - /* Cache malloc_getpagesize */ - unsigned int pagesize; - - /* Track properties of MORECORE */ - unsigned int morecore_properties; - - /* Statistics */ - INTERNAL_SIZE_T mmapped_mem; - INTERNAL_SIZE_T sbrked_mem; - INTERNAL_SIZE_T max_sbrked_mem; - INTERNAL_SIZE_T max_mmapped_mem; - INTERNAL_SIZE_T max_total_mem; -}; - -typedef struct malloc_state *mstate; - -/* - There is exactly one instance of this struct in this malloc. - If you are adapting this malloc in a way that does NOT use a static - malloc_state, you MUST explicitly zero-fill it before using. This - malloc relies on the property that malloc_state is initialized to - all zeroes (as is true of C statics). -*/ - -static struct malloc_state av_; /* never directly referenced */ - -/* - All uses of av_ are via get_malloc_state(). - At most one "call" to get_malloc_state is made per invocation of - the public versions of malloc and free, but other routines - that in turn invoke malloc and/or free may call more then once. - Also, it is called in check* routines if DEBUG is set. -*/ - -#define get_malloc_state() (&(av_)) - -/* - Initialize a malloc_state struct. - - This is called only from within malloc_consolidate, which needs - be called in the same contexts anyway. It is never called directly - outside of malloc_consolidate because some optimizing compilers try - to inline it at all call points, which turns out not to be an - optimization at all. (Inlining it in malloc_consolidate is fine though.) -*/ - -#if __STD_C -static void malloc_init_state(mstate av) -#else -static void malloc_init_state(av) mstate av; -#endif -{ - int i; - mbinptr bin; - - /* Establish circular links for normal bins */ - for (i = 1; i < NBINS; ++i) { - bin = bin_at(av,i); - bin->fd = bin->bk = bin; - } - - av->top_pad = DEFAULT_TOP_PAD; - av->n_mmaps_max = DEFAULT_MMAP_MAX; - av->mmap_threshold = DEFAULT_MMAP_THRESHOLD; - av->trim_threshold = DEFAULT_TRIM_THRESHOLD; - -#if MORECORE_CONTIGUOUS - set_contiguous(av); -#else - set_noncontiguous(av); -#endif - - - set_max_fast(av, DEFAULT_MXFAST); - - av->top = initial_top(av); - av->pagesize = malloc_getpagesize; -} - -/* - Other internal utilities operating on mstates -*/ - -static Void_t* sYSMALLOc(INTERNAL_SIZE_T, mstate); -#ifndef MORECORE_CANNOT_TRIM -static int sYSTRIm(size_t, mstate); -#endif -static void malloc_consolidate(mstate); -static Void_t** iALLOc(size_t, size_t*, int, Void_t**); - -/* - Debugging support - - These routines make a number of assertions about the states - of data structures that should be true at all times. If any - are not true, it's very likely that a user program has somehow - trashed memory. (It's also possible that there is a coding error - in malloc. In which case, please report it!) -*/ - -#if ! DEBUG - -#define check_chunk(P) -#define check_free_chunk(P) -#define check_inuse_chunk(P) -#define check_remalloced_chunk(P,N) -#define check_malloced_chunk(P,N) -#define check_malloc_state() - -#else -#define check_chunk(P) do_check_chunk(P) -#define check_free_chunk(P) do_check_free_chunk(P) -#define check_inuse_chunk(P) do_check_inuse_chunk(P) -#define check_remalloced_chunk(P,N) do_check_remalloced_chunk(P,N) -#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N) -#define check_malloc_state() do_check_malloc_state() - -/* - Properties of all chunks -*/ - -#if __STD_C -static void do_check_chunk(mchunkptr p) -#else -static void do_check_chunk(p) mchunkptr p; -#endif -{ - mstate av = get_malloc_state(); - CHUNK_SIZE_T sz = chunksize(p); - /* min and max possible addresses assuming contiguous allocation */ - char* max_address = (char*)(av->top) + chunksize(av->top); - char* min_address = max_address - av->sbrked_mem; - - if (!chunk_is_mmapped(p)) { - - /* Has legal address ... */ - if (p != av->top) { - if (contiguous(av)) { - assert(((char*)p) >= min_address); - assert(((char*)p + sz) <= ((char*)(av->top))); - } - } - else { - /* top size is always at least MINSIZE */ - assert((CHUNK_SIZE_T)(sz) >= MINSIZE); - /* top predecessor always marked inuse */ - assert(prev_inuse(p)); - } - - } - else { -#if HAVE_MMAP - /* address is outside main heap */ - if (contiguous(av) && av->top != initial_top(av)) { - assert(((char*)p) < min_address || ((char*)p) > max_address); - } - /* chunk is page-aligned */ - assert(((p->prev_size + sz) & (av->pagesize-1)) == 0); - /* mem is aligned */ - assert(aligned_OK(chunk2mem(p))); -#else - /* force an appropriate assert violation if debug set */ - assert(!chunk_is_mmapped(p)); -#endif - } -} - -/* - Properties of free chunks -*/ - -#if __STD_C -static void do_check_free_chunk(mchunkptr p) -#else -static void do_check_free_chunk(p) mchunkptr p; -#endif -{ - mstate av = get_malloc_state(); - - INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; - mchunkptr next = chunk_at_offset(p, sz); - - do_check_chunk(p); - - /* Chunk must claim to be free ... */ - assert(!inuse(p)); - assert (!chunk_is_mmapped(p)); - - /* Unless a special marker, must have OK fields */ - if ((CHUNK_SIZE_T)(sz) >= MINSIZE) - { - assert((sz & MALLOC_ALIGN_MASK) == 0); - assert(aligned_OK(chunk2mem(p))); - /* ... matching footer field */ - assert(next->prev_size == sz); - /* ... and is fully consolidated */ - assert(prev_inuse(p)); - assert (next == av->top || inuse(next)); - - /* ... and has minimally sane links */ - assert(p->fd->bk == p); - assert(p->bk->fd == p); - } - else /* markers are always of size SIZE_SZ */ - assert(sz == SIZE_SZ); -} - -/* - Properties of inuse chunks -*/ - -#if __STD_C -static void do_check_inuse_chunk(mchunkptr p) -#else -static void do_check_inuse_chunk(p) mchunkptr p; -#endif -{ - mstate av = get_malloc_state(); - mchunkptr next; - do_check_chunk(p); - - if (chunk_is_mmapped(p)) - return; /* mmapped chunks have no next/prev */ - - /* Check whether it claims to be in use ... */ - assert(inuse(p)); - - next = next_chunk(p); - - /* ... and is surrounded by OK chunks. - Since more things can be checked with free chunks than inuse ones, - if an inuse chunk borders them and debug is on, it's worth doing them. - */ - if (!prev_inuse(p)) { - /* Note that we cannot even look at prev unless it is not inuse */ - mchunkptr prv = prev_chunk(p); - assert(next_chunk(prv) == p); - do_check_free_chunk(prv); - } - - if (next == av->top) { - assert(prev_inuse(next)); - assert(chunksize(next) >= MINSIZE); - } - else if (!inuse(next)) - do_check_free_chunk(next); -} - -/* - Properties of chunks recycled from fastbins -*/ - -#if __STD_C -static void do_check_remalloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) -#else -static void do_check_remalloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; -#endif -{ - INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE; - - do_check_inuse_chunk(p); - - /* Legal size ... */ - assert((sz & MALLOC_ALIGN_MASK) == 0); - assert((CHUNK_SIZE_T)(sz) >= MINSIZE); - /* ... and alignment */ - assert(aligned_OK(chunk2mem(p))); - /* chunk is less than MINSIZE more than request */ - assert((long)(sz) - (long)(s) >= 0); - assert((long)(sz) - (long)(s + MINSIZE) < 0); -} - -/* - Properties of nonrecycled chunks at the point they are malloced -*/ - -#if __STD_C -static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s) -#else -static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s; -#endif -{ - /* same as recycled case ... */ - do_check_remalloced_chunk(p, s); - - /* - ... plus, must obey implementation invariant that prev_inuse is - always true of any allocated chunk; i.e., that each allocated - chunk borders either a previously allocated and still in-use - chunk, or the base of its memory arena. This is ensured - by making all allocations from the the `lowest' part of any found - chunk. This does not necessarily hold however for chunks - recycled via fastbins. - */ - - assert(prev_inuse(p)); -} - - -/* - Properties of malloc_state. - - This may be useful for debugging malloc, as well as detecting user - programmer errors that somehow write into malloc_state. - - If you are extending or experimenting with this malloc, you can - probably figure out how to hack this routine to print out or - display chunk addresses, sizes, bins, and other instrumentation. -*/ - -static void do_check_malloc_state() -{ - mstate av = get_malloc_state(); - int i; - mchunkptr p; - mchunkptr q; - mbinptr b; - unsigned int binbit; - int empty; - unsigned int idx; - INTERNAL_SIZE_T size; - CHUNK_SIZE_T total = 0; - int max_fast_bin; - - /* internal size_t must be no wider than pointer type */ - assert(sizeof(INTERNAL_SIZE_T) <= sizeof(char*)); - - /* alignment is a power of 2 */ - assert((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-1)) == 0); - - /* cannot run remaining checks until fully initialized */ - if (av->top == 0 || av->top == initial_top(av)) - return; - - /* pagesize is a power of 2 */ - assert((av->pagesize & (av->pagesize-1)) == 0); - - /* properties of fastbins */ - - /* max_fast is in allowed range */ - assert(get_max_fast(av) <= request2size(MAX_FAST_SIZE)); - - max_fast_bin = fastbin_index(av->max_fast); - - for (i = 0; i < NFASTBINS; ++i) { - p = av->fastbins[i]; - - /* all bins past max_fast are empty */ - if (i > max_fast_bin) - assert(p == 0); - - while (p != 0) { - /* each chunk claims to be inuse */ - do_check_inuse_chunk(p); - total += chunksize(p); - /* chunk belongs in this bin */ - assert(fastbin_index(chunksize(p)) == i); - p = p->fd; - } - } - - if (total != 0) - assert(have_fastchunks(av)); - else if (!have_fastchunks(av)) - assert(total == 0); - - /* check normal bins */ - for (i = 1; i < NBINS; ++i) { - b = bin_at(av,i); - - /* binmap is accurate (except for bin 1 == unsorted_chunks) */ - if (i >= 2) { - binbit = get_binmap(av,i); - empty = last(b) == b; - if (!binbit) - assert(empty); - else if (!empty) - assert(binbit); - } - - for (p = last(b); p != b; p = p->bk) { - /* each chunk claims to be free */ - do_check_free_chunk(p); - size = chunksize(p); - total += size; - if (i >= 2) { - /* chunk belongs in bin */ - idx = bin_index(size); - assert(idx == i); - /* lists are sorted */ - if ((CHUNK_SIZE_T) size >= (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) { - assert(p->bk == b || - (CHUNK_SIZE_T)chunksize(p->bk) >= - (CHUNK_SIZE_T)chunksize(p)); - } - } - /* chunk is followed by a legal chain of inuse chunks */ - for (q = next_chunk(p); - (q != av->top && inuse(q) && - (CHUNK_SIZE_T)(chunksize(q)) >= MINSIZE); - q = next_chunk(q)) - do_check_inuse_chunk(q); - } - } - - /* top chunk is OK */ - check_chunk(av->top); - - /* sanity checks for statistics */ - - assert(total <= (CHUNK_SIZE_T)(av->max_total_mem)); - assert(av->n_mmaps >= 0); - assert(av->n_mmaps <= av->max_n_mmaps); - - assert((CHUNK_SIZE_T)(av->sbrked_mem) <= - (CHUNK_SIZE_T)(av->max_sbrked_mem)); - - assert((CHUNK_SIZE_T)(av->mmapped_mem) <= - (CHUNK_SIZE_T)(av->max_mmapped_mem)); - - assert((CHUNK_SIZE_T)(av->max_total_mem) >= - (CHUNK_SIZE_T)(av->mmapped_mem) + (CHUNK_SIZE_T)(av->sbrked_mem)); -} -#endif - - -/* ----------- Routines dealing with system allocation -------------- */ - -/* - sysmalloc handles malloc cases requiring more memory from the system. - On entry, it is assumed that av->top does not have enough - space to service request for nb bytes, thus requiring that av->top - be extended or replaced. -*/ - -#if __STD_C -static Void_t* sYSMALLOc(INTERNAL_SIZE_T nb, mstate av) -#else -static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av; -#endif -{ - mchunkptr old_top; /* incoming value of av->top */ - INTERNAL_SIZE_T old_size; /* its size */ - char* old_end; /* its end address */ - - long size; /* arg to first MORECORE or mmap call */ - char* brk; /* return value from MORECORE */ - - long correction; /* arg to 2nd MORECORE call */ - char* snd_brk; /* 2nd return val */ - - INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */ - INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */ - char* aligned_brk; /* aligned offset into brk */ - - mchunkptr p; /* the allocated/returned chunk */ - mchunkptr remainder; /* remainder from allocation */ - CHUNK_SIZE_T remainder_size; /* its size */ - - CHUNK_SIZE_T sum; /* for updating stats */ - - size_t pagemask = av->pagesize - 1; - - /* - If there is space available in fastbins, consolidate and retry - malloc from scratch rather than getting memory from system. This - can occur only if nb is in smallbin range so we didn't consolidate - upon entry to malloc. It is much easier to handle this case here - than in malloc proper. - */ - - if (have_fastchunks(av)) { - assert(in_smallbin_range(nb)); - malloc_consolidate(av); - return mALLOc(nb - MALLOC_ALIGN_MASK); - } - - -#if HAVE_MMAP - - /* - If have mmap, and the request size meets the mmap threshold, and - the system supports mmap, and there are few enough currently - allocated mmapped regions, try to directly map this request - rather than expanding top. - */ - - if ((CHUNK_SIZE_T)(nb) >= (CHUNK_SIZE_T)(av->mmap_threshold) && - (av->n_mmaps < av->n_mmaps_max)) { - - char* mm; /* return value from mmap call*/ - - /* - Round up size to nearest page. For mmapped chunks, the overhead - is one SIZE_SZ unit larger than for normal chunks, because there - is no following chunk whose prev_size field could be used. - */ - size = (nb + SIZE_SZ + MALLOC_ALIGN_MASK + pagemask) & ~pagemask; - - /* Don't try if size wraps around 0 */ - if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) { - - mm = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE)); - - if (mm != (char*)(MORECORE_FAILURE)) { - - /* - The offset to the start of the mmapped region is stored - in the prev_size field of the chunk. This allows us to adjust - returned start address to meet alignment requirements here - and in memalign(), and still be able to compute proper - address argument for later munmap in free() and realloc(). - */ - - front_misalign = (INTERNAL_SIZE_T)chunk2mem(mm) & MALLOC_ALIGN_MASK; - if (front_misalign > 0) { - correction = MALLOC_ALIGNMENT - front_misalign; - p = (mchunkptr)(mm + correction); - p->prev_size = correction; - set_head(p, (size - correction) |IS_MMAPPED); - } - else { - p = (mchunkptr)mm; - p->prev_size = 0; - set_head(p, size|IS_MMAPPED); - } - - /* update statistics */ - - if (++av->n_mmaps > av->max_n_mmaps) - av->max_n_mmaps = av->n_mmaps; - - sum = av->mmapped_mem += size; - if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem)) - av->max_mmapped_mem = sum; - sum += av->sbrked_mem; - if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) - av->max_total_mem = sum; - - check_chunk(p); - - return chunk2mem(p); - } - } - } -#endif - - /* Record incoming configuration of top */ - - old_top = av->top; - old_size = chunksize(old_top); - old_end = (char*)(chunk_at_offset(old_top, old_size)); - - brk = snd_brk = (char*)(MORECORE_FAILURE); - - /* - If not the first time through, we require old_size to be - at least MINSIZE and to have prev_inuse set. - */ - - assert((old_top == initial_top(av) && old_size == 0) || - ((CHUNK_SIZE_T) (old_size) >= MINSIZE && - prev_inuse(old_top))); - - /* Precondition: not enough current space to satisfy nb request */ - assert((CHUNK_SIZE_T)(old_size) < (CHUNK_SIZE_T)(nb + MINSIZE)); - - /* Precondition: all fastbins are consolidated */ - assert(!have_fastchunks(av)); - - - /* Request enough space for nb + pad + overhead */ - - size = nb + av->top_pad + MINSIZE; - - /* - If contiguous, we can subtract out existing space that we hope to - combine with new space. We add it back later only if - we don't actually get contiguous space. - */ - - if (contiguous(av)) - size -= old_size; - - /* - Round to a multiple of page size. - If MORECORE is not contiguous, this ensures that we only call it - with whole-page arguments. And if MORECORE is contiguous and - this is not first time through, this preserves page-alignment of - previous calls. Otherwise, we correct to page-align below. - */ - - size = (size + pagemask) & ~pagemask; - - /* - Don't try to call MORECORE if argument is so big as to appear - negative. Note that since mmap takes size_t arg, it may succeed - below even if we cannot call MORECORE. - */ - - if (size > 0) - brk = (char*)(MORECORE(size)); - - /* - If have mmap, try using it as a backup when MORECORE fails or - cannot be used. This is worth doing on systems that have "holes" in - address space, so sbrk cannot extend to give contiguous space, but - space is available elsewhere. Note that we ignore mmap max count - and threshold limits, since the space will not be used as a - segregated mmap region. - */ - -#if HAVE_MMAP - if (brk == (char*)(MORECORE_FAILURE)) { - - /* Cannot merge with old top, so add its size back in */ - if (contiguous(av)) - size = (size + old_size + pagemask) & ~pagemask; - - /* If we are relying on mmap as backup, then use larger units */ - if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(MMAP_AS_MORECORE_SIZE)) - size = MMAP_AS_MORECORE_SIZE; - - /* Don't try if size wraps around 0 */ - if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) { - - brk = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE)); - - if (brk != (char*)(MORECORE_FAILURE)) { - - /* We do not need, and cannot use, another sbrk call to find end */ - snd_brk = brk + size; - - /* - Record that we no longer have a contiguous sbrk region. - After the first time mmap is used as backup, we do not - ever rely on contiguous space since this could incorrectly - bridge regions. - */ - set_noncontiguous(av); - } - } - } -#endif - - if (brk != (char*)(MORECORE_FAILURE)) { - av->sbrked_mem += size; - - /* - If MORECORE extends previous space, we can likewise extend top size. - */ - - if (brk == old_end && snd_brk == (char*)(MORECORE_FAILURE)) { - set_head(old_top, (size + old_size) | PREV_INUSE); - } - - /* - Otherwise, make adjustments: - - * If the first time through or noncontiguous, we need to call sbrk - just to find out where the end of memory lies. - - * We need to ensure that all returned chunks from malloc will meet - MALLOC_ALIGNMENT - - * If there was an intervening foreign sbrk, we need to adjust sbrk - request size to account for fact that we will not be able to - combine new space with existing space in old_top. - - * Almost all systems internally allocate whole pages at a time, in - which case we might as well use the whole last page of request. - So we allocate enough more memory to hit a page boundary now, - which in turn causes future contiguous calls to page-align. - */ - - else { - front_misalign = 0; - end_misalign = 0; - correction = 0; - aligned_brk = brk; - - /* - If MORECORE returns an address lower than we have seen before, - we know it isn't really contiguous. This and some subsequent - checks help cope with non-conforming MORECORE functions and - the presence of "foreign" calls to MORECORE from outside of - malloc or by other threads. We cannot guarantee to detect - these in all cases, but cope with the ones we do detect. - */ - if (contiguous(av) && old_size != 0 && brk < old_end) { - set_noncontiguous(av); - } - - /* handle contiguous cases */ - if (contiguous(av)) { - - /* - We can tolerate forward non-contiguities here (usually due - to foreign calls) but treat them as part of our space for - stats reporting. - */ - if (old_size != 0) - av->sbrked_mem += brk - old_end; - - /* Guarantee alignment of first new chunk made from this space */ - - front_misalign = (INTERNAL_SIZE_T)chunk2mem(brk) & MALLOC_ALIGN_MASK; - if (front_misalign > 0) { - - /* - Skip over some bytes to arrive at an aligned position. - We don't need to specially mark these wasted front bytes. - They will never be accessed anyway because - prev_inuse of av->top (and any chunk created from its start) - is always true after initialization. - */ - - correction = MALLOC_ALIGNMENT - front_misalign; - aligned_brk += correction; - } - - /* - If this isn't adjacent to existing space, then we will not - be able to merge with old_top space, so must add to 2nd request. - */ - - correction += old_size; - - /* Extend the end address to hit a page boundary */ - end_misalign = (INTERNAL_SIZE_T)(brk + size + correction); - correction += ((end_misalign + pagemask) & ~pagemask) - end_misalign; - - assert(correction >= 0); - snd_brk = (char*)(MORECORE(correction)); - - if (snd_brk == (char*)(MORECORE_FAILURE)) { - /* - If can't allocate correction, try to at least find out current - brk. It might be enough to proceed without failing. - */ - correction = 0; - snd_brk = (char*)(MORECORE(0)); - } - else if (snd_brk < brk) { - /* - If the second call gives noncontiguous space even though - it says it won't, the only course of action is to ignore - results of second call, and conservatively estimate where - the first call left us. Also set noncontiguous, so this - won't happen again, leaving at most one hole. - - Note that this check is intrinsically incomplete. Because - MORECORE is allowed to give more space than we ask for, - there is no reliable way to detect a noncontiguity - producing a forward gap for the second call. - */ - snd_brk = brk + size; - correction = 0; - set_noncontiguous(av); - } - - } - - /* handle non-contiguous cases */ - else { - /* MORECORE/mmap must correctly align */ - assert(aligned_OK(chunk2mem(brk))); - - /* Find out current end of memory */ - if (snd_brk == (char*)(MORECORE_FAILURE)) { - snd_brk = (char*)(MORECORE(0)); - av->sbrked_mem += snd_brk - brk - size; - } - } - - /* Adjust top based on results of second sbrk */ - if (snd_brk != (char*)(MORECORE_FAILURE)) { - av->top = (mchunkptr)aligned_brk; - set_head(av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE); - av->sbrked_mem += correction; - - /* - If not the first time through, we either have a - gap due to foreign sbrk or a non-contiguous region. Insert a - double fencepost at old_top to prevent consolidation with space - we don't own. These fenceposts are artificial chunks that are - marked as inuse and are in any case too small to use. We need - two to make sizes and alignments work out. - */ - - if (old_size != 0) { - /* - Shrink old_top to insert fenceposts, keeping size a - multiple of MALLOC_ALIGNMENT. We know there is at least - enough space in old_top to do this. - */ - old_size = (old_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK; - set_head(old_top, old_size | PREV_INUSE); - - /* - Note that the following assignments completely overwrite - old_top when old_size was previously MINSIZE. This is - intentional. We need the fencepost, even if old_top otherwise gets - lost. - */ - chunk_at_offset(old_top, old_size )->size = - SIZE_SZ|PREV_INUSE; - - chunk_at_offset(old_top, old_size + SIZE_SZ)->size = - SIZE_SZ|PREV_INUSE; - - /* - If possible, release the rest, suppressing trimming. - */ - if (old_size >= MINSIZE) { - INTERNAL_SIZE_T tt = av->trim_threshold; - av->trim_threshold = (INTERNAL_SIZE_T)(-1); - fREe(chunk2mem(old_top)); - av->trim_threshold = tt; - } - } - } - } - - /* Update statistics */ - sum = av->sbrked_mem; - if (sum > (CHUNK_SIZE_T)(av->max_sbrked_mem)) - av->max_sbrked_mem = sum; - - sum += av->mmapped_mem; - if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) - av->max_total_mem = sum; - - check_malloc_state(); - - /* finally, do the allocation */ - - p = av->top; - size = chunksize(p); - - /* check that one of the above allocation paths succeeded */ - if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) { - remainder_size = size - nb; - remainder = chunk_at_offset(p, nb); - av->top = remainder; - set_head(p, nb | PREV_INUSE); - set_head(remainder, remainder_size | PREV_INUSE); - check_malloced_chunk(p, nb); - return chunk2mem(p); - } - - } - - /* catch all failure paths */ - MALLOC_FAILURE_ACTION; - return 0; -} - - - - -#ifndef MORECORE_CANNOT_TRIM -/* - sYSTRIm is an inverse of sorts to sYSMALLOc. It gives memory back - to the system (via negative arguments to sbrk) if there is unused - memory at the `high' end of the malloc pool. It is called - automatically by free() when top space exceeds the trim - threshold. It is also called by the public malloc_trim routine. It - returns 1 if it actually released any memory, else 0. -*/ - -#if __STD_C -static int sYSTRIm(size_t pad, mstate av) -#else -static int sYSTRIm(pad, av) size_t pad; mstate av; -#endif -{ - long top_size; /* Amount of top-most memory */ - long extra; /* Amount to release */ - long released; /* Amount actually released */ - char* current_brk; /* address returned by pre-check sbrk call */ - char* new_brk; /* address returned by post-check sbrk call */ - size_t pagesz; - - pagesz = av->pagesize; - top_size = chunksize(av->top); - - /* Release in pagesize units, keeping at least one page */ - extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz; - - if (extra > 0) { - - /* - Only proceed if end of memory is where we last set it. - This avoids problems if there were foreign sbrk calls. - */ - current_brk = (char*)(MORECORE(0)); - if (current_brk == (char*)(av->top) + top_size) { - - /* - Attempt to release memory. We ignore MORECORE return value, - and instead call again to find out where new end of memory is. - This avoids problems if first call releases less than we asked, - of if failure somehow altered brk value. (We could still - encounter problems if it altered brk in some very bad way, - but the only thing we can do is adjust anyway, which will cause - some downstream failure.) - */ - - MORECORE(-extra); - new_brk = (char*)(MORECORE(0)); - - if (new_brk != (char*)MORECORE_FAILURE) { - released = (long)(current_brk - new_brk); - - if (released != 0) { - /* Success. Adjust top. */ - av->sbrked_mem -= released; - set_head(av->top, (top_size - released) | PREV_INUSE); - check_malloc_state(); - return 1; - } - } - } - } - return 0; -} -#endif - -/* - ------------------------------ malloc ------------------------------ -*/ - - -#if __STD_C -Void_t* mALLOc(size_t bytes) -#else - Void_t* mALLOc(bytes) size_t bytes; -#endif -{ - mstate av = get_malloc_state(); - - INTERNAL_SIZE_T nb; /* normalized request size */ - unsigned int idx; /* associated bin index */ - mbinptr bin; /* associated bin */ - mfastbinptr* fb; /* associated fastbin */ - - mchunkptr victim; /* inspected/selected chunk */ - INTERNAL_SIZE_T size; /* its size */ - int victim_index; /* its bin index */ - - mchunkptr remainder; /* remainder from a split */ - CHUNK_SIZE_T remainder_size; /* its size */ - - unsigned int block; /* bit map traverser */ - unsigned int bit; /* bit map traverser */ - unsigned int map; /* current word of binmap */ - - mchunkptr fwd; /* misc temp for linking */ - mchunkptr bck; /* misc temp for linking */ - - /* - Convert request size to internal form by adding SIZE_SZ bytes - overhead plus possibly more to obtain necessary alignment and/or - to obtain a size of at least MINSIZE, the smallest allocatable - size. Also, checked_request2size traps (returning 0) request sizes - that are so large that they wrap around zero when padded and - aligned. - */ - - checked_request2size(bytes, nb); - - /* - Bypass search if no frees yet - */ - if (!have_anychunks(av)) { - if (av->max_fast == 0) /* initialization check */ - malloc_consolidate(av); - goto use_top; - } - - /* - If the size qualifies as a fastbin, first check corresponding bin. - */ - - if ((CHUNK_SIZE_T)(nb) <= (CHUNK_SIZE_T)(av->max_fast)) { - fb = &(av->fastbins[(fastbin_index(nb))]); - if ( (victim = *fb) != 0) { - *fb = victim->fd; - check_remalloced_chunk(victim, nb); - return chunk2mem(victim); - } - } - - /* - If a small request, check regular bin. Since these "smallbins" - hold one size each, no searching within bins is necessary. - (For a large request, we need to wait until unsorted chunks are - processed to find best fit. But for small ones, fits are exact - anyway, so we can check now, which is faster.) - */ - - if (in_smallbin_range(nb)) { - idx = smallbin_index(nb); - bin = bin_at(av,idx); - - if ( (victim = last(bin)) != bin) { - bck = victim->bk; - set_inuse_bit_at_offset(victim, nb); - bin->bk = bck; - bck->fd = bin; - - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - } - - /* - If this is a large request, consolidate fastbins before continuing. - While it might look excessive to kill all fastbins before - even seeing if there is space available, this avoids - fragmentation problems normally associated with fastbins. - Also, in practice, programs tend to have runs of either small or - large requests, but less often mixtures, so consolidation is not - invoked all that often in most programs. And the programs that - it is called frequently in otherwise tend to fragment. - */ - - else { - idx = largebin_index(nb); - if (have_fastchunks(av)) - malloc_consolidate(av); - } - - /* - Process recently freed or remaindered chunks, taking one only if - it is exact fit, or, if this a small request, the chunk is remainder from - the most recent non-exact fit. Place other traversed chunks in - bins. Note that this step is the only place in any routine where - chunks are placed in bins. - */ - - while ( (victim = unsorted_chunks(av)->bk) != unsorted_chunks(av)) { - bck = victim->bk; - size = chunksize(victim); - - /* - If a small request, try to use last remainder if it is the - only chunk in unsorted bin. This helps promote locality for - runs of consecutive small requests. This is the only - exception to best-fit, and applies only when there is - no exact fit for a small chunk. - */ - - if (in_smallbin_range(nb) && - bck == unsorted_chunks(av) && - victim == av->last_remainder && - (CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) { - - /* split and reattach remainder */ - remainder_size = size - nb; - remainder = chunk_at_offset(victim, nb); - unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; - av->last_remainder = remainder; - remainder->bk = remainder->fd = unsorted_chunks(av); - - set_head(victim, nb | PREV_INUSE); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); - - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - - /* remove from unsorted list */ - unsorted_chunks(av)->bk = bck; - bck->fd = unsorted_chunks(av); - - /* Take now instead of binning if exact fit */ - - if (size == nb) { - set_inuse_bit_at_offset(victim, size); - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - - /* place chunk in bin */ - - if (in_smallbin_range(size)) { - victim_index = smallbin_index(size); - bck = bin_at(av, victim_index); - fwd = bck->fd; - } - else { - victim_index = largebin_index(size); - bck = bin_at(av, victim_index); - fwd = bck->fd; - - if (fwd != bck) { - /* if smaller than smallest, place first */ - if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(bck->bk->size)) { - fwd = bck; - bck = bck->bk; - } - else if ((CHUNK_SIZE_T)(size) >= - (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) { - - /* maintain large bins in sorted order */ - size |= PREV_INUSE; /* Or with inuse bit to speed comparisons */ - while ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(fwd->size)) - fwd = fwd->fd; - bck = fwd->bk; - } - } - } - - mark_bin(av, victim_index); - victim->bk = bck; - victim->fd = fwd; - fwd->bk = victim; - bck->fd = victim; - } - - /* - If a large request, scan through the chunks of current bin to - find one that fits. (This will be the smallest that fits unless - FIRST_SORTED_BIN_SIZE has been changed from default.) This is - the only step where an unbounded number of chunks might be - scanned without doing anything useful with them. However the - lists tend to be short. - */ - - if (!in_smallbin_range(nb)) { - bin = bin_at(av, idx); - - for (victim = last(bin); victim != bin; victim = victim->bk) { - size = chunksize(victim); - - if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)) { - remainder_size = size - nb; - unlink(victim, bck, fwd); - - /* Exhaust */ - if (remainder_size < MINSIZE) { - set_inuse_bit_at_offset(victim, size); - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - /* Split */ - else { - remainder = chunk_at_offset(victim, nb); - unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; - remainder->bk = remainder->fd = unsorted_chunks(av); - set_head(victim, nb | PREV_INUSE); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - } - } - } - - /* - Search for a chunk by scanning bins, starting with next largest - bin. This search is strictly by best-fit; i.e., the smallest - (with ties going to approximately the least recently used) chunk - that fits is selected. - - The bitmap avoids needing to check that most blocks are nonempty. - */ - - ++idx; - bin = bin_at(av,idx); - block = idx2block(idx); - map = av->binmap[block]; - bit = idx2bit(idx); - - for (;;) { - - /* Skip rest of block if there are no more set bits in this block. */ - if (bit > map || bit == 0) { - do { - if (++block >= BINMAPSIZE) /* out of bins */ - goto use_top; - } while ( (map = av->binmap[block]) == 0); - - bin = bin_at(av, (block << BINMAPSHIFT)); - bit = 1; - } - - /* Advance to bin with set bit. There must be one. */ - while ((bit & map) == 0) { - bin = next_bin(bin); - bit <<= 1; - assert(bit != 0); - } - - /* Inspect the bin. It is likely to be non-empty */ - victim = last(bin); - - /* If a false alarm (empty bin), clear the bit. */ - if (victim == bin) { - av->binmap[block] = map &= ~bit; /* Write through */ - bin = next_bin(bin); - bit <<= 1; - } - - else { - size = chunksize(victim); - - /* We know the first chunk in this bin is big enough to use. */ - assert((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)); - - remainder_size = size - nb; - - /* unlink */ - bck = victim->bk; - bin->bk = bck; - bck->fd = bin; - - /* Exhaust */ - if (remainder_size < MINSIZE) { - set_inuse_bit_at_offset(victim, size); - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - - /* Split */ - else { - remainder = chunk_at_offset(victim, nb); - - unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder; - remainder->bk = remainder->fd = unsorted_chunks(av); - /* advertise as last remainder */ - if (in_smallbin_range(nb)) - av->last_remainder = remainder; - - set_head(victim, nb | PREV_INUSE); - set_head(remainder, remainder_size | PREV_INUSE); - set_foot(remainder, remainder_size); - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - } - } - - use_top: - /* - If large enough, split off the chunk bordering the end of memory - (held in av->top). Note that this is in accord with the best-fit - search rule. In effect, av->top is treated as larger (and thus - less well fitting) than any other available chunk since it can - be extended to be as large as necessary (up to system - limitations). - - We require that av->top always exists (i.e., has size >= - MINSIZE) after initialization, so if it would otherwise be - exhuasted by current request, it is replenished. (The main - reason for ensuring it exists is that we may need MINSIZE space - to put in fenceposts in sysmalloc.) - */ - - victim = av->top; - size = chunksize(victim); - - if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) { - remainder_size = size - nb; - remainder = chunk_at_offset(victim, nb); - av->top = remainder; - set_head(victim, nb | PREV_INUSE); - set_head(remainder, remainder_size | PREV_INUSE); - - check_malloced_chunk(victim, nb); - return chunk2mem(victim); - } - - /* - If no space in top, relay to handle system-dependent cases - */ - return sYSMALLOc(nb, av); -} - -/* - ------------------------------ free ------------------------------ -*/ - -#if __STD_C -void fREe(Void_t* mem) -#else -void fREe(mem) Void_t* mem; -#endif -{ - mstate av = get_malloc_state(); - - mchunkptr p; /* chunk corresponding to mem */ - INTERNAL_SIZE_T size; /* its size */ - mfastbinptr* fb; /* associated fastbin */ - mchunkptr nextchunk; /* next contiguous chunk */ - INTERNAL_SIZE_T nextsize; /* its size */ - int nextinuse; /* true if nextchunk is used */ - INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */ - mchunkptr bck; /* misc temp for linking */ - mchunkptr fwd; /* misc temp for linking */ - - /* free(0) has no effect */ - if (mem != 0) { - p = mem2chunk(mem); - size = chunksize(p); - - check_inuse_chunk(p); - - /* - If eligible, place chunk on a fastbin so it can be found - and used quickly in malloc. - */ - - if ((CHUNK_SIZE_T)(size) <= (CHUNK_SIZE_T)(av->max_fast) - -#if TRIM_FASTBINS - /* - If TRIM_FASTBINS set, don't place chunks - bordering top into fastbins - */ - && (chunk_at_offset(p, size) != av->top) -#endif - ) { - - set_fastchunks(av); - fb = &(av->fastbins[fastbin_index(size)]); - p->fd = *fb; - *fb = p; - } - - /* - Consolidate other non-mmapped chunks as they arrive. - */ - - else if (!chunk_is_mmapped(p)) { - set_anychunks(av); - - nextchunk = chunk_at_offset(p, size); - nextsize = chunksize(nextchunk); - - /* consolidate backward */ - if (!prev_inuse(p)) { - prevsize = p->prev_size; - size += prevsize; - p = chunk_at_offset(p, -((long) prevsize)); - unlink(p, bck, fwd); - } - - if (nextchunk != av->top) { - /* get and clear inuse bit */ - nextinuse = inuse_bit_at_offset(nextchunk, nextsize); - set_head(nextchunk, nextsize); - - /* consolidate forward */ - if (!nextinuse) { - unlink(nextchunk, bck, fwd); - size += nextsize; - } - - /* - Place the chunk in unsorted chunk list. Chunks are - not placed into regular bins until after they have - been given one chance to be used in malloc. - */ - - bck = unsorted_chunks(av); - fwd = bck->fd; - p->bk = bck; - p->fd = fwd; - bck->fd = p; - fwd->bk = p; - - set_head(p, size | PREV_INUSE); - set_foot(p, size); - - check_free_chunk(p); - } - - /* - If the chunk borders the current high end of memory, - consolidate into top - */ - - else { - size += nextsize; - set_head(p, size | PREV_INUSE); - av->top = p; - check_chunk(p); - } - - /* - If freeing a large space, consolidate possibly-surrounding - chunks. Then, if the total unused topmost memory exceeds trim - threshold, ask malloc_trim to reduce top. - - Unless max_fast is 0, we don't know if there are fastbins - bordering top, so we cannot tell for sure whether threshold - has been reached unless fastbins are consolidated. But we - don't want to consolidate on each free. As a compromise, - consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD - is reached. - */ - - if ((CHUNK_SIZE_T)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD) { - if (have_fastchunks(av)) - malloc_consolidate(av); - -#ifndef MORECORE_CANNOT_TRIM - if ((CHUNK_SIZE_T)(chunksize(av->top)) >= - (CHUNK_SIZE_T)(av->trim_threshold)) - sYSTRIm(av->top_pad, av); -#endif - } - - } - /* - If the chunk was allocated via mmap, release via munmap() - Note that if HAVE_MMAP is false but chunk_is_mmapped is - true, then user must have overwritten memory. There's nothing - we can do to catch this error unless DEBUG is set, in which case - check_inuse_chunk (above) will have triggered error. - */ - - else { -#if HAVE_MMAP - int ret; - INTERNAL_SIZE_T offset = p->prev_size; - av->n_mmaps--; - av->mmapped_mem -= (size + offset); - ret = munmap((char*)p - offset, size + offset); - /* munmap returns non-zero on failure */ - assert(ret == 0); -#endif - } - } -} - -/* - ------------------------- malloc_consolidate ------------------------- - - malloc_consolidate is a specialized version of free() that tears - down chunks held in fastbins. Free itself cannot be used for this - purpose since, among other things, it might place chunks back onto - fastbins. So, instead, we need to use a minor variant of the same - code. - - Also, because this routine needs to be called the first time through - malloc anyway, it turns out to be the perfect place to trigger - initialization code. -*/ - -#if __STD_C -static void malloc_consolidate(mstate av) -#else -static void malloc_consolidate(av) mstate av; -#endif -{ - mfastbinptr* fb; /* current fastbin being consolidated */ - mfastbinptr* maxfb; /* last fastbin (for loop control) */ - mchunkptr p; /* current chunk being consolidated */ - mchunkptr nextp; /* next chunk to consolidate */ - mchunkptr unsorted_bin; /* bin header */ - mchunkptr first_unsorted; /* chunk to link to */ - - /* These have same use as in free() */ - mchunkptr nextchunk; - INTERNAL_SIZE_T size; - INTERNAL_SIZE_T nextsize; - INTERNAL_SIZE_T prevsize; - int nextinuse; - mchunkptr bck; - mchunkptr fwd; - - /* - If max_fast is 0, we know that av hasn't - yet been initialized, in which case do so below - */ - - if (av->max_fast != 0) { - clear_fastchunks(av); - - unsorted_bin = unsorted_chunks(av); - - /* - Remove each chunk from fast bin and consolidate it, placing it - then in unsorted bin. Among other reasons for doing this, - placing in unsorted bin avoids needing to calculate actual bins - until malloc is sure that chunks aren't immediately going to be - reused anyway. - */ - - maxfb = &(av->fastbins[fastbin_index(av->max_fast)]); - fb = &(av->fastbins[0]); - do { - if ( (p = *fb) != 0) { - *fb = 0; - - do { - check_inuse_chunk(p); - nextp = p->fd; - - /* Slightly streamlined version of consolidation code in free() */ - size = p->size & ~PREV_INUSE; - nextchunk = chunk_at_offset(p, size); - nextsize = chunksize(nextchunk); - - if (!prev_inuse(p)) { - prevsize = p->prev_size; - size += prevsize; - p = chunk_at_offset(p, -((long) prevsize)); - unlink(p, bck, fwd); - } - - if (nextchunk != av->top) { - nextinuse = inuse_bit_at_offset(nextchunk, nextsize); - set_head(nextchunk, nextsize); - - if (!nextinuse) { - size += nextsize; - unlink(nextchunk, bck, fwd); - } - - first_unsorted = unsorted_bin->fd; - unsorted_bin->fd = p; - first_unsorted->bk = p; - - set_head(p, size | PREV_INUSE); - p->bk = unsorted_bin; - p->fd = first_unsorted; - set_foot(p, size); - } - - else { - size += nextsize; - set_head(p, size | PREV_INUSE); - av->top = p; - } - - } while ( (p = nextp) != 0); - - } - } while (fb++ != maxfb); - } - else { - malloc_init_state(av); - check_malloc_state(); - } -} - -/* - ------------------------------ realloc ------------------------------ -*/ - - -#if __STD_C -Void_t* rEALLOc(Void_t* oldmem, size_t bytes) -#else -Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; -#endif -{ - mstate av = get_malloc_state(); - - INTERNAL_SIZE_T nb; /* padded request size */ - - mchunkptr oldp; /* chunk corresponding to oldmem */ - INTERNAL_SIZE_T oldsize; /* its size */ - - mchunkptr newp; /* chunk to return */ - INTERNAL_SIZE_T newsize; /* its size */ - Void_t* newmem; /* corresponding user mem */ - - mchunkptr next; /* next contiguous chunk after oldp */ - - mchunkptr remainder; /* extra space at end of newp */ - CHUNK_SIZE_T remainder_size; /* its size */ - - mchunkptr bck; /* misc temp for linking */ - mchunkptr fwd; /* misc temp for linking */ - - CHUNK_SIZE_T copysize; /* bytes to copy */ - unsigned int ncopies; /* INTERNAL_SIZE_T words to copy */ - INTERNAL_SIZE_T* s; /* copy source */ - INTERNAL_SIZE_T* d; /* copy destination */ - - -#ifdef REALLOC_ZERO_BYTES_FREES - if (bytes == 0) { - fREe(oldmem); - return 0; - } -#endif - - /* realloc of null is supposed to be same as malloc */ - if (oldmem == 0) return mALLOc(bytes); - - checked_request2size(bytes, nb); - - oldp = mem2chunk(oldmem); - oldsize = chunksize(oldp); - - check_inuse_chunk(oldp); - - if (!chunk_is_mmapped(oldp)) { - - if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb)) { - /* already big enough; split below */ - newp = oldp; - newsize = oldsize; - } - - else { - next = chunk_at_offset(oldp, oldsize); - - /* Try to expand forward into top */ - if (next == av->top && - (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >= - (CHUNK_SIZE_T)(nb + MINSIZE)) { - set_head_size(oldp, nb); - av->top = chunk_at_offset(oldp, nb); - set_head(av->top, (newsize - nb) | PREV_INUSE); - return chunk2mem(oldp); - } - - /* Try to expand forward into next chunk; split off remainder below */ - else if (next != av->top && - !inuse(next) && - (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >= - (CHUNK_SIZE_T)(nb)) { - newp = oldp; - unlink(next, bck, fwd); - } - - /* allocate, copy, free */ - else { - newmem = mALLOc(nb - MALLOC_ALIGN_MASK); - if (newmem == 0) - return 0; /* propagate failure */ - - newp = mem2chunk(newmem); - newsize = chunksize(newp); - - /* - Avoid copy if newp is next chunk after oldp. - */ - if (newp == next) { - newsize += oldsize; - newp = oldp; - } - else { - /* - Unroll copy of <= 36 bytes (72 if 8byte sizes) - We know that contents have an odd number of - INTERNAL_SIZE_T-sized words; minimally 3. - */ - - copysize = oldsize - SIZE_SZ; - s = (INTERNAL_SIZE_T*)(oldmem); - d = (INTERNAL_SIZE_T*)(newmem); - ncopies = copysize / sizeof(INTERNAL_SIZE_T); - assert(ncopies >= 3); - - if (ncopies > 9) - MALLOC_COPY(d, s, copysize); - - else { - *(d+0) = *(s+0); - *(d+1) = *(s+1); - *(d+2) = *(s+2); - if (ncopies > 4) { - *(d+3) = *(s+3); - *(d+4) = *(s+4); - if (ncopies > 6) { - *(d+5) = *(s+5); - *(d+6) = *(s+6); - if (ncopies > 8) { - *(d+7) = *(s+7); - *(d+8) = *(s+8); - } - } - } - } - - fREe(oldmem); - check_inuse_chunk(newp); - return chunk2mem(newp); - } - } - } - - /* If possible, free extra space in old or extended chunk */ - - assert((CHUNK_SIZE_T)(newsize) >= (CHUNK_SIZE_T)(nb)); - - remainder_size = newsize - nb; - - if (remainder_size < MINSIZE) { /* not enough extra to split off */ - set_head_size(newp, newsize); - set_inuse_bit_at_offset(newp, newsize); - } - else { /* split remainder */ - remainder = chunk_at_offset(newp, nb); - set_head_size(newp, nb); - set_head(remainder, remainder_size | PREV_INUSE); - /* Mark remainder as inuse so free() won't complain */ - set_inuse_bit_at_offset(remainder, remainder_size); - fREe(chunk2mem(remainder)); - } - - check_inuse_chunk(newp); - return chunk2mem(newp); - } - - /* - Handle mmap cases - */ - - else { -#if HAVE_MMAP - -#if HAVE_MREMAP - INTERNAL_SIZE_T offset = oldp->prev_size; - size_t pagemask = av->pagesize - 1; - char *cp; - CHUNK_SIZE_T sum; - - /* Note the extra SIZE_SZ overhead */ - newsize = (nb + offset + SIZE_SZ + pagemask) & ~pagemask; - - /* don't need to remap if still within same page */ - if (oldsize == newsize - offset) - return oldmem; - - cp = (char*)mremap((char*)oldp - offset, oldsize + offset, newsize, 1); - - if (cp != (char*)MORECORE_FAILURE) { - - newp = (mchunkptr)(cp + offset); - set_head(newp, (newsize - offset)|IS_MMAPPED); - - assert(aligned_OK(chunk2mem(newp))); - assert((newp->prev_size == offset)); - - /* update statistics */ - sum = av->mmapped_mem += newsize - oldsize; - if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem)) - av->max_mmapped_mem = sum; - sum += av->sbrked_mem; - if (sum > (CHUNK_SIZE_T)(av->max_total_mem)) - av->max_total_mem = sum; - - return chunk2mem(newp); - } -#endif - - /* Note the extra SIZE_SZ overhead. */ - if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb + SIZE_SZ)) - newmem = oldmem; /* do nothing */ - else { - /* Must alloc, copy, free. */ - newmem = mALLOc(nb - MALLOC_ALIGN_MASK); - if (newmem != 0) { - MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); - fREe(oldmem); - } - } - return newmem; - -#else - /* If !HAVE_MMAP, but chunk_is_mmapped, user must have overwritten mem */ - check_malloc_state(); - MALLOC_FAILURE_ACTION; - return 0; -#endif - } -} - -/* - ------------------------------ memalign ------------------------------ -*/ - -#if __STD_C -Void_t* mEMALIGn(size_t alignment, size_t bytes) -#else -Void_t* mEMALIGn(alignment, bytes) size_t alignment; size_t bytes; -#endif -{ - INTERNAL_SIZE_T nb; /* padded request size */ - char* m; /* memory returned by malloc call */ - mchunkptr p; /* corresponding chunk */ - char* brk; /* alignment point within p */ - mchunkptr newp; /* chunk to return */ - INTERNAL_SIZE_T newsize; /* its size */ - INTERNAL_SIZE_T leadsize; /* leading space before alignment point */ - mchunkptr remainder; /* spare room at end to split off */ - CHUNK_SIZE_T remainder_size; /* its size */ - INTERNAL_SIZE_T size; - - /* If need less alignment than we give anyway, just relay to malloc */ - - if (alignment <= MALLOC_ALIGNMENT) return mALLOc(bytes); - - /* Otherwise, ensure that it is at least a minimum chunk size */ - - if (alignment < MINSIZE) alignment = MINSIZE; - - /* Make sure alignment is power of 2 (in case MINSIZE is not). */ - if ((alignment & (alignment - 1)) != 0) { - size_t a = MALLOC_ALIGNMENT * 2; - while ((CHUNK_SIZE_T)a < (CHUNK_SIZE_T)alignment) a <<= 1; - alignment = a; - } - - checked_request2size(bytes, nb); - - /* - Strategy: find a spot within that chunk that meets the alignment - request, and then possibly free the leading and trailing space. - */ - - - /* Call malloc with worst case padding to hit alignment. */ - - m = (char*)(mALLOc(nb + alignment + MINSIZE)); - - if (m == 0) return 0; /* propagate failure */ - - p = mem2chunk(m); - - if ((((PTR_UINT)(m)) % alignment) != 0) { /* misaligned */ - - /* - Find an aligned spot inside chunk. Since we need to give back - leading space in a chunk of at least MINSIZE, if the first - calculation places us at a spot with less than MINSIZE leader, - we can move to the next aligned spot -- we've allocated enough - total room so that this is always possible. - */ - - brk = (char*)mem2chunk((PTR_UINT)(((PTR_UINT)(m + alignment - 1)) & - -((signed long) alignment))); - if ((CHUNK_SIZE_T)(brk - (char*)(p)) < MINSIZE) - brk += alignment; - - newp = (mchunkptr)brk; - leadsize = brk - (char*)(p); - newsize = chunksize(p) - leadsize; - - /* For mmapped chunks, just adjust offset */ - if (chunk_is_mmapped(p)) { - newp->prev_size = p->prev_size + leadsize; - set_head(newp, newsize|IS_MMAPPED); - return chunk2mem(newp); - } - - /* Otherwise, give back leader, use the rest */ - set_head(newp, newsize | PREV_INUSE); - set_inuse_bit_at_offset(newp, newsize); - set_head_size(p, leadsize); - fREe(chunk2mem(p)); - p = newp; - - assert (newsize >= nb && - (((PTR_UINT)(chunk2mem(p))) % alignment) == 0); - } - - /* Also give back spare room at the end */ - if (!chunk_is_mmapped(p)) { - size = chunksize(p); - if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) { - remainder_size = size - nb; - remainder = chunk_at_offset(p, nb); - set_head(remainder, remainder_size | PREV_INUSE); - set_head_size(p, nb); - fREe(chunk2mem(remainder)); - } - } - - check_inuse_chunk(p); - return chunk2mem(p); -} - -/* - ------------------------------ calloc ------------------------------ -*/ - -#if __STD_C -Void_t* cALLOc(size_t n_elements, size_t elem_size) -#else -Void_t* cALLOc(n_elements, elem_size) size_t n_elements; size_t elem_size; -#endif -{ - mchunkptr p; - CHUNK_SIZE_T clearsize; - CHUNK_SIZE_T nclears; - INTERNAL_SIZE_T* d; - - Void_t* mem = mALLOc(n_elements * elem_size); - - if (mem != 0) { - p = mem2chunk(mem); - - if (!chunk_is_mmapped(p)) - { - /* - Unroll clear of <= 36 bytes (72 if 8byte sizes) - We know that contents have an odd number of - INTERNAL_SIZE_T-sized words; minimally 3. - */ - - d = (INTERNAL_SIZE_T*)mem; - clearsize = chunksize(p) - SIZE_SZ; - nclears = clearsize / sizeof(INTERNAL_SIZE_T); - assert(nclears >= 3); - - if (nclears > 9) - MALLOC_ZERO(d, clearsize); - - else { - *(d+0) = 0; - *(d+1) = 0; - *(d+2) = 0; - if (nclears > 4) { - *(d+3) = 0; - *(d+4) = 0; - if (nclears > 6) { - *(d+5) = 0; - *(d+6) = 0; - if (nclears > 8) { - *(d+7) = 0; - *(d+8) = 0; - } - } - } - } - } -#if ! MMAP_CLEARS - else - { - d = (INTERNAL_SIZE_T*)mem; - /* - Note the additional SIZE_SZ - */ - clearsize = chunksize(p) - 2*SIZE_SZ; - MALLOC_ZERO(d, clearsize); - } -#endif - } - return mem; -} - -/* - ------------------------------ cfree ------------------------------ -*/ - -#if __STD_C -void cFREe(Void_t *mem) -#else -void cFREe(mem) Void_t *mem; -#endif -{ - fREe(mem); -} - -/* - ------------------------- independent_calloc ------------------------- -*/ - -#if __STD_C -Void_t** iCALLOc(size_t n_elements, size_t elem_size, Void_t* chunks[]) -#else -Void_t** iCALLOc(n_elements, elem_size, chunks) size_t n_elements; size_t elem_size; Void_t* chunks[]; -#endif -{ - size_t sz = elem_size; /* serves as 1-element array */ - /* opts arg of 3 means all elements are same size, and should be cleared */ - return iALLOc(n_elements, &sz, 3, chunks); -} - -/* - ------------------------- independent_comalloc ------------------------- -*/ - -#if __STD_C -Void_t** iCOMALLOc(size_t n_elements, size_t sizes[], Void_t* chunks[]) -#else -Void_t** iCOMALLOc(n_elements, sizes, chunks) size_t n_elements; size_t sizes[]; Void_t* chunks[]; -#endif -{ - return iALLOc(n_elements, sizes, 0, chunks); -} - - -/* - ------------------------------ ialloc ------------------------------ - ialloc provides common support for independent_X routines, handling all of - the combinations that can result. - - The opts arg has: - bit 0 set if all elements are same size (using sizes[0]) - bit 1 set if elements should be zeroed -*/ - - -#if __STD_C -static Void_t** iALLOc(size_t n_elements, - size_t* sizes, - int opts, - Void_t* chunks[]) -#else -static Void_t** iALLOc(n_elements, sizes, opts, chunks) size_t n_elements; size_t* sizes; int opts; Void_t* chunks[]; -#endif -{ - mstate av = get_malloc_state(); - INTERNAL_SIZE_T element_size; /* chunksize of each element, if all same */ - INTERNAL_SIZE_T contents_size; /* total size of elements */ - INTERNAL_SIZE_T array_size; /* request size of pointer array */ - Void_t* mem; /* malloced aggregate space */ - mchunkptr p; /* corresponding chunk */ - INTERNAL_SIZE_T remainder_size; /* remaining bytes while splitting */ - Void_t** marray; /* either "chunks" or malloced ptr array */ - mchunkptr array_chunk; /* chunk for malloced ptr array */ - int mmx; /* to disable mmap */ - INTERNAL_SIZE_T size; - size_t i; - - /* Ensure initialization */ - if (av->max_fast == 0) malloc_consolidate(av); - - /* compute array length, if needed */ - if (chunks != 0) { - if (n_elements == 0) - return chunks; /* nothing to do */ - marray = chunks; - array_size = 0; - } - else { - /* if empty req, must still return chunk representing empty array */ - if (n_elements == 0) - return (Void_t**) mALLOc(0); - marray = 0; - array_size = request2size(n_elements * (sizeof(Void_t*))); - } - - /* compute total element size */ - if (opts & 0x1) { /* all-same-size */ - element_size = request2size(*sizes); - contents_size = n_elements * element_size; - } - else { /* add up all the sizes */ - element_size = 0; - contents_size = 0; - for (i = 0; i != n_elements; ++i) - contents_size += request2size(sizes[i]); - } - - /* subtract out alignment bytes from total to minimize overallocation */ - size = contents_size + array_size - MALLOC_ALIGN_MASK; - - /* - Allocate the aggregate chunk. - But first disable mmap so malloc won't use it, since - we would not be able to later free/realloc space internal - to a segregated mmap region. - */ - mmx = av->n_mmaps_max; /* disable mmap */ - av->n_mmaps_max = 0; - mem = mALLOc(size); - av->n_mmaps_max = mmx; /* reset mmap */ - if (mem == 0) - return 0; - - p = mem2chunk(mem); - assert(!chunk_is_mmapped(p)); - remainder_size = chunksize(p); - - if (opts & 0x2) { /* optionally clear the elements */ - MALLOC_ZERO(mem, remainder_size - SIZE_SZ - array_size); - } - - /* If not provided, allocate the pointer array as final part of chunk */ - if (marray == 0) { - array_chunk = chunk_at_offset(p, contents_size); - marray = (Void_t**) (chunk2mem(array_chunk)); - set_head(array_chunk, (remainder_size - contents_size) | PREV_INUSE); - remainder_size = contents_size; - } - - /* split out elements */ - for (i = 0; ; ++i) { - marray[i] = chunk2mem(p); - if (i != n_elements-1) { - if (element_size != 0) - size = element_size; - else - size = request2size(sizes[i]); - remainder_size -= size; - set_head(p, size | PREV_INUSE); - p = chunk_at_offset(p, size); - } - else { /* the final element absorbs any overallocation slop */ - set_head(p, remainder_size | PREV_INUSE); - break; - } - } - -#if DEBUG - if (marray != chunks) { - /* final element must have exactly exhausted chunk */ - if (element_size != 0) - assert(remainder_size == element_size); - else - assert(remainder_size == request2size(sizes[i])); - check_inuse_chunk(mem2chunk(marray)); - } - - for (i = 0; i != n_elements; ++i) - check_inuse_chunk(mem2chunk(marray[i])); -#endif - - return marray; -} - - -/* - ------------------------------ valloc ------------------------------ -*/ - -#if __STD_C -Void_t* vALLOc(size_t bytes) -#else -Void_t* vALLOc(bytes) size_t bytes; -#endif -{ - /* Ensure initialization */ - mstate av = get_malloc_state(); - if (av->max_fast == 0) malloc_consolidate(av); - return mEMALIGn(av->pagesize, bytes); -} - -/* - ------------------------------ pvalloc ------------------------------ -*/ - - -#if __STD_C -Void_t* pVALLOc(size_t bytes) -#else -Void_t* pVALLOc(bytes) size_t bytes; -#endif -{ - mstate av = get_malloc_state(); - size_t pagesz; - - /* Ensure initialization */ - if (av->max_fast == 0) malloc_consolidate(av); - pagesz = av->pagesize; - return mEMALIGn(pagesz, (bytes + pagesz - 1) & ~(pagesz - 1)); -} - - -/* - ------------------------------ malloc_trim ------------------------------ -*/ - -#if __STD_C -int mTRIm(size_t pad) -#else -int mTRIm(pad) size_t pad; -#endif -{ - mstate av = get_malloc_state(); - /* Ensure initialization/consolidation */ - malloc_consolidate(av); - -#ifndef MORECORE_CANNOT_TRIM - return sYSTRIm(pad, av); -#else - return 0; -#endif -} - - -/* - ------------------------- malloc_usable_size ------------------------- -*/ - -#if __STD_C -size_t mUSABLe(Void_t* mem) -#else -size_t mUSABLe(mem) Void_t* mem; -#endif -{ - mchunkptr p; - if (mem != 0) { - p = mem2chunk(mem); - if (chunk_is_mmapped(p)) - return chunksize(p) - 2*SIZE_SZ; - else if (inuse(p)) - return chunksize(p) - SIZE_SZ; - } - return 0; -} - -/* - ------------------------------ mallinfo ------------------------------ -*/ - -struct mallinfo mALLINFo() -{ - mstate av = get_malloc_state(); - struct mallinfo mi; - int i; - mbinptr b; - mchunkptr p; - INTERNAL_SIZE_T avail; - INTERNAL_SIZE_T fastavail; - int nblocks; - int nfastblocks; - - /* Ensure initialization */ - if (av->top == 0) malloc_consolidate(av); - - check_malloc_state(); - - /* Account for top */ - avail = chunksize(av->top); - nblocks = 1; /* top always exists */ - - /* traverse fastbins */ - nfastblocks = 0; - fastavail = 0; - - for (i = 0; i < NFASTBINS; ++i) { - for (p = av->fastbins[i]; p != 0; p = p->fd) { - ++nfastblocks; - fastavail += chunksize(p); - } - } - - avail += fastavail; - - /* traverse regular bins */ - for (i = 1; i < NBINS; ++i) { - b = bin_at(av, i); - for (p = last(b); p != b; p = p->bk) { - ++nblocks; - avail += chunksize(p); - } - } - - mi.smblks = nfastblocks; - mi.ordblks = nblocks; - mi.fordblks = avail; - mi.uordblks = av->sbrked_mem - avail; - mi.arena = av->sbrked_mem; - mi.hblks = av->n_mmaps; - mi.hblkhd = av->mmapped_mem; - mi.fsmblks = fastavail; - mi.keepcost = chunksize(av->top); - mi.usmblks = av->max_total_mem; - return mi; -} - -/* - ------------------------------ malloc_stats ------------------------------ -*/ - -void mSTATs() -{ - struct mallinfo mi = mALLINFo(); - -#ifdef WIN32 - { - CHUNK_SIZE_T free, reserved, committed; - vminfo (&free, &reserved, &committed); - fprintf(stderr, "free bytes = %10lu\n", - free); - fprintf(stderr, "reserved bytes = %10lu\n", - reserved); - fprintf(stderr, "committed bytes = %10lu\n", - committed); - } -#endif - -/* RN XXX */ - printf("max system bytes = %10lu\n", - (CHUNK_SIZE_T)(mi.usmblks)); - printf("system bytes = %10lu\n", - (CHUNK_SIZE_T)(mi.arena + mi.hblkhd)); - printf("in use bytes = %10lu\n", - (CHUNK_SIZE_T)(mi.uordblks + mi.hblkhd)); - -#ifdef WIN32 - { - CHUNK_SIZE_T kernel, user; - if (cpuinfo (TRUE, &kernel, &user)) { - fprintf(stderr, "kernel ms = %10lu\n", - kernel); - fprintf(stderr, "user ms = %10lu\n", - user); - } - } -#endif -} - - -/* - ------------------------------ mallopt ------------------------------ -*/ - -#if __STD_C -int mALLOPt(int param_number, int value) -#else -int mALLOPt(param_number, value) int param_number; int value; -#endif -{ - mstate av = get_malloc_state(); - /* Ensure initialization/consolidation */ - malloc_consolidate(av); - - switch(param_number) { - case M_MXFAST: - if (value >= 0 && value <= MAX_FAST_SIZE) { - set_max_fast(av, value); - return 1; - } - else - return 0; - - case M_TRIM_THRESHOLD: - av->trim_threshold = value; - return 1; - - case M_TOP_PAD: - av->top_pad = value; - return 1; - - case M_MMAP_THRESHOLD: - av->mmap_threshold = value; - return 1; - - case M_MMAP_MAX: -#if !HAVE_MMAP - if (value != 0) - return 0; -#endif - av->n_mmaps_max = value; - return 1; - - default: - return 0; - } -} - - -/* - -------------------- Alternative MORECORE functions -------------------- -*/ - - -/* - General Requirements for MORECORE. - - The MORECORE function must have the following properties: - - If MORECORE_CONTIGUOUS is false: - - * MORECORE must allocate in multiples of pagesize. It will - only be called with arguments that are multiples of pagesize. - - * MORECORE(0) must return an address that is at least - MALLOC_ALIGNMENT aligned. (Page-aligning always suffices.) - - else (i.e. If MORECORE_CONTIGUOUS is true): - - * Consecutive calls to MORECORE with positive arguments - return increasing addresses, indicating that space has been - contiguously extended. - - * MORECORE need not allocate in multiples of pagesize. - Calls to MORECORE need not have args of multiples of pagesize. - - * MORECORE need not page-align. - - In either case: - - * MORECORE may allocate more memory than requested. (Or even less, - but this will generally result in a malloc failure.) - - * MORECORE must not allocate memory when given argument zero, but - instead return one past the end address of memory from previous - nonzero call. This malloc does NOT call MORECORE(0) - until at least one call with positive arguments is made, so - the initial value returned is not important. - - * Even though consecutive calls to MORECORE need not return contiguous - addresses, it must be OK for malloc'ed chunks to span multiple - regions in those cases where they do happen to be contiguous. - - * MORECORE need not handle negative arguments -- it may instead - just return MORECORE_FAILURE when given negative arguments. - Negative arguments are always multiples of pagesize. MORECORE - must not misinterpret negative args as large positive unsigned - args. You can suppress all such calls from even occurring by defining - MORECORE_CANNOT_TRIM, - - There is some variation across systems about the type of the - argument to sbrk/MORECORE. If size_t is unsigned, then it cannot - actually be size_t, because sbrk supports negative args, so it is - normally the signed type of the same width as size_t (sometimes - declared as "intptr_t", and sometimes "ptrdiff_t"). It doesn't much - matter though. Internally, we use "long" as arguments, which should - work across all reasonable possibilities. - - Additionally, if MORECORE ever returns failure for a positive - request, and HAVE_MMAP is true, then mmap is used as a noncontiguous - system allocator. This is a useful backup strategy for systems with - holes in address spaces -- in this case sbrk cannot contiguously - expand the heap, but mmap may be able to map noncontiguous space. - - If you'd like mmap to ALWAYS be used, you can define MORECORE to be - a function that always returns MORECORE_FAILURE. - - Malloc only has limited ability to detect failures of MORECORE - to supply contiguous space when it says it can. In particular, - multithreaded programs that do not use locks may result in - rece conditions across calls to MORECORE that result in gaps - that cannot be detected as such, and subsequent corruption. - - If you are using this malloc with something other than sbrk (or its - emulation) to supply memory regions, you probably want to set - MORECORE_CONTIGUOUS as false. As an example, here is a custom - allocator kindly contributed for pre-OSX macOS. It uses virtually - but not necessarily physically contiguous non-paged memory (locked - in, present and won't get swapped out). You can use it by - uncommenting this section, adding some #includes, and setting up the - appropriate defines above: - - #define MORECORE osMoreCore - #define MORECORE_CONTIGUOUS 0 - - There is also a shutdown routine that should somehow be called for - cleanup upon program exit. - - #define MAX_POOL_ENTRIES 100 - #define MINIMUM_MORECORE_SIZE (64 * 1024) - static int next_os_pool; - void *our_os_pools[MAX_POOL_ENTRIES]; - - void *osMoreCore(int size) - { - void *ptr = 0; - static void *sbrk_top = 0; - - if (size > 0) - { - if (size < MINIMUM_MORECORE_SIZE) - size = MINIMUM_MORECORE_SIZE; - if (CurrentExecutionLevel() == kTaskLevel) - ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0); - if (ptr == 0) - { - return (void *) MORECORE_FAILURE; - } - // save ptrs so they can be freed during cleanup - our_os_pools[next_os_pool] = ptr; - next_os_pool++; - ptr = (void *) ((((CHUNK_SIZE_T) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK); - sbrk_top = (char *) ptr + size; - return ptr; - } - else if (size < 0) - { - // we don't currently support shrink behavior - return (void *) MORECORE_FAILURE; - } - else - { - return sbrk_top; - } - } - - // cleanup any allocated memory pools - // called as last thing before shutting down driver - - void osCleanupMem(void) - { - void **ptr; - - for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++) - if (*ptr) - { - PoolDeallocate(*ptr); - *ptr = 0; - } - } - -*/ - - -/* - -------------------------------------------------------------- - - Emulation of sbrk for win32. - Donated by J. Walter <Walter@xxxxxxxxxxxx>. - For additional information about this code, and malloc on Win32, see - http://www.genesys-e.de/jwalter/ -*/ - - -#ifdef WIN32 - -#ifdef _DEBUG -/* #define TRACE */ -#endif - -/* Support for USE_MALLOC_LOCK */ -#ifdef USE_MALLOC_LOCK - -/* Wait for spin lock */ -static int slwait (int *sl) { - while (InterlockedCompareExchange ((void **) sl, (void *) 1, (void *) 0) != 0) - Sleep (0); - return 0; -} - -/* Release spin lock */ -static int slrelease (int *sl) { - InterlockedExchange (sl, 0); - return 0; -} - -#ifdef NEEDED -/* Spin lock for emulation code */ -static int g_sl; -#endif - -#endif /* USE_MALLOC_LOCK */ - -/* getpagesize for windows */ -static long getpagesize (void) { - static long g_pagesize = 0; - if (! g_pagesize) { - SYSTEM_INFO system_info; - GetSystemInfo (&system_info); - g_pagesize = system_info.dwPageSize; - } - return g_pagesize; -} -static long getregionsize (void) { - static long g_regionsize = 0; - if (! g_regionsize) { - SYSTEM_INFO system_info; - GetSystemInfo (&system_info); - g_regionsize = system_info.dwAllocationGranularity; - } - return g_regionsize; -} - -/* A region list entry */ -typedef struct _region_list_entry { - void *top_allocated; - void *top_committed; - void *top_reserved; - long reserve_size; - struct _region_list_entry *previous; -} region_list_entry; - -/* Allocate and link a region entry in the region list */ -static int region_list_append (region_list_entry **last, void *base_reserved, long reserve_size) { - region_list_entry *next = HeapAlloc (GetProcessHeap (), 0, sizeof (region_list_entry)); - if (! next) - return FALSE; - next->top_allocated = (char *) base_reserved; - next->top_committed = (char *) base_reserved; - next->top_reserved = (char *) base_reserved + reserve_size; - next->reserve_size = reserve_size; - next->previous = *last; - *last = next; - return TRUE; -} -/* Free and unlink the last region entry from the region list */ -static int region_list_remove (region_list_entry **last) { - region_list_entry *previous = (*last)->previous; - if (! HeapFree (GetProcessHeap (), sizeof (region_list_entry), *last)) - return FALSE; - *last = previous; - return TRUE; -} - -#define CEIL(size,to) (((size)+(to)-1)&~((to)-1)) -#define FLOOR(size,to) ((size)&~((to)-1)) - -#define SBRK_SCALE 0 -/* #define SBRK_SCALE 1 */ -/* #define SBRK_SCALE 2 */ -/* #define SBRK_SCALE 4 */ - -/* sbrk for windows */ -static void *sbrk (long size) { - static long g_pagesize, g_my_pagesize; - static long g_regionsize, g_my_regionsize; - static region_list_entry *g_last; - void *result = (void *) MORECORE_FAILURE; -#ifdef TRACE - printf ("sbrk %d\n", size); -#endif -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Wait for spin lock */ - slwait (&g_sl); -#endif - /* First time initialization */ - if (! g_pagesize) { - g_pagesize = getpagesize (); - g_my_pagesize = g_pagesize << SBRK_SCALE; - } - if (! g_regionsize) { - g_regionsize = getregionsize (); - g_my_regionsize = g_regionsize << SBRK_SCALE; - } - if (! g_last) { - if (! region_list_append (&g_last, 0, 0)) - goto sbrk_exit; - } - /* Assert invariants */ - assert (g_last); - assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated && - g_last->top_allocated <= g_last->top_committed); - assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed && - g_last->top_committed <= g_last->top_reserved && - (unsigned) g_last->top_committed % g_pagesize == 0); - assert ((unsigned) g_last->top_reserved % g_regionsize == 0); - assert ((unsigned) g_last->reserve_size % g_regionsize == 0); - /* Allocation requested? */ - if (size >= 0) { - /* Allocation size is the requested size */ - long allocate_size = size; - /* Compute the size to commit */ - long to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed; - /* Do we reach the commit limit? */ - if (to_commit > 0) { - /* Round size to commit */ - long commit_size = CEIL (to_commit, g_my_pagesize); - /* Compute the size to reserve */ - long to_reserve = (char *) g_last->top_committed + commit_size - (char *) g_last->top_reserved; - /* Do we reach the reserve limit? */ - if (to_reserve > 0) { - /* Compute the remaining size to commit in the current region */ - long remaining_commit_size = (char *) g_last->top_reserved - (char *) g_last->top_committed; - if (remaining_commit_size > 0) { - /* Assert preconditions */ - assert ((unsigned) g_last->top_committed % g_pagesize == 0); - assert (0 < remaining_commit_size && remaining_commit_size % g_pagesize == 0); { - /* Commit this */ - void *base_committed = VirtualAlloc (g_last->top_committed, remaining_commit_size, - MEM_COMMIT, PAGE_READWRITE); - /* Check returned pointer for consistency */ - if (base_committed != g_last->top_committed) - goto sbrk_exit; - /* Assert postconditions */ - assert ((unsigned) base_committed % g_pagesize == 0); -#ifdef TRACE - printf ("Commit %p %d\n", base_committed, remaining_commit_size); -#endif - /* Adjust the regions commit top */ - g_last->top_committed = (char *) base_committed + remaining_commit_size; - } - } { - /* Now we are going to search and reserve. */ - int contiguous = -1; - int found = FALSE; - MEMORY_BASIC_INFORMATION memory_info; - void *base_reserved; - long reserve_size; - do { - /* Assume contiguous memory */ - contiguous = TRUE; - /* Round size to reserve */ - reserve_size = CEIL (to_reserve, g_my_regionsize); - /* Start with the current region's top */ - memory_info.BaseAddress = g_last->top_reserved; - /* Assert preconditions */ - assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0); - assert (0 < reserve_size && reserve_size % g_regionsize == 0); - while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) { - /* Assert postconditions */ - assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0); -#ifdef TRACE - printf ("Query %p %d %s\n", memory_info.BaseAddress, memory_info.RegionSize, - memory_info.State == MEM_FREE ? "FREE": - (memory_info.State == MEM_RESERVE ? "RESERVED": - (memory_info.State == MEM_COMMIT ? "COMMITTED": "?"))); -#endif - /* Region is free, well aligned and big enough: we are done */ - if (memory_info.State == MEM_FREE && - (unsigned) memory_info.BaseAddress % g_regionsize == 0 && - memory_info.RegionSize >= (unsigned) reserve_size) { - found = TRUE; - break; - } - /* From now on we can't get contiguous memory! */ - contiguous = FALSE; - /* Recompute size to reserve */ - reserve_size = CEIL (allocate_size, g_my_regionsize); - memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize; - /* Assert preconditions */ - assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0); - assert (0 < reserve_size && reserve_size % g_regionsize == 0); - } - /* Search failed? */ - if (! found) - goto sbrk_exit; - /* Assert preconditions */ - assert ((unsigned) memory_info.BaseAddress % g_regionsize == 0); - assert (0 < reserve_size && reserve_size % g_regionsize == 0); - /* Try to reserve this */ - base_reserved = VirtualAlloc (memory_info.BaseAddress, reserve_size, - MEM_RESERVE, PAGE_NOACCESS); - if (! base_reserved) { - int rc = GetLastError (); - if (rc != ERROR_INVALID_ADDRESS) - goto sbrk_exit; - } - /* A null pointer signals (hopefully) a race condition with another thread. */ - /* In this case, we try again. */ - } while (! base_reserved); - /* Check returned pointer for consistency */ - if (memory_info.BaseAddress && base_reserved != memory_info.BaseAddress) - goto sbrk_exit; - /* Assert postconditions */ - assert ((unsigned) base_reserved % g_regionsize == 0); -#ifdef TRACE - printf ("Reserve %p %d\n", base_reserved, reserve_size); -#endif - /* Did we get contiguous memory? */ - if (contiguous) { - long start_size = (char *) g_last->top_committed - (char *) g_last->top_allocated; - /* Adjust allocation size */ - allocate_size -= start_size; - /* Adjust the regions allocation top */ - g_last->top_allocated = g_last->top_committed; - /* Recompute the size to commit */ - to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed; - /* Round size to commit */ - commit_size = CEIL (to_commit, g_my_pagesize); - } - /* Append the new region to the list */ - if (! region_list_append (&g_last, base_reserved, reserve_size)) - goto sbrk_exit; - /* Didn't we get contiguous memory? */ - if (! contiguous) { - /* Recompute the size to commit */ - to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed; - /* Round size to commit */ - commit_size = CEIL (to_commit, g_my_pagesize); - } - } - } - /* Assert preconditions */ - assert ((unsigned) g_last->top_committed % g_pagesize == 0); - assert (0 < commit_size && commit_size % g_pagesize == 0); { - /* Commit this */ - void *base_committed = VirtualAlloc (g_last->top_committed, commit_size, - MEM_COMMIT, PAGE_READWRITE); - /* Check returned pointer for consistency */ - if (base_committed != g_last->top_committed) - goto sbrk_exit; - /* Assert postconditions */ - assert ((unsigned) base_committed % g_pagesize == 0); -#ifdef TRACE - printf ("Commit %p %d\n", base_committed, commit_size); -#endif - /* Adjust the regions commit top */ - g_last->top_committed = (char *) base_committed + commit_size; - } - } - /* Adjust the regions allocation top */ - g_last->top_allocated = (char *) g_last->top_allocated + allocate_size; - result = (char *) g_last->top_allocated - size; - /* Deallocation requested? */ - } else if (size < 0) { - long deallocate_size = - size; - /* As long as we have a region to release */ - while ((char *) g_last->top_allocated - deallocate_size < (char *) g_last->top_reserved - g_last->reserve_size) { - /* Get the size to release */ - long release_size = g_last->reserve_size; - /* Get the base address */ - void *base_reserved = (char *) g_last->top_reserved - release_size; - /* Assert preconditions */ - assert ((unsigned) base_reserved % g_regionsize == 0); - assert (0 < release_size && release_size % g_regionsize == 0); { - /* Release this */ - int rc = VirtualFree (base_reserved, 0, - MEM_RELEASE); - /* Check returned code for consistency */ - if (! rc) - goto sbrk_exit; -#ifdef TRACE - printf ("Release %p %d\n", base_reserved, release_size); -#endif - } - /* Adjust deallocation size */ - deallocate_size -= (char *) g_last->top_allocated - (char *) base_reserved; - /* Remove the old region from the list */ - if (! region_list_remove (&g_last)) - goto sbrk_exit; - } { - /* Compute the size to decommit */ - long to_decommit = (char *) g_last->top_committed - ((char *) g_last->top_allocated - deallocate_size); - if (to_decommit >= g_my_pagesize) { - /* Compute the size to decommit */ - long decommit_size = FLOOR (to_decommit, g_my_pagesize); - /* Compute the base address */ - void *base_committed = (char *) g_last->top_committed - decommit_size; - /* Assert preconditions */ - assert ((unsigned) base_committed % g_pagesize == 0); - assert (0 < decommit_size && decommit_size % g_pagesize == 0); { - /* Decommit this */ - int rc = VirtualFree ((char *) base_committed, decommit_size, - MEM_DECOMMIT); - /* Check returned code for consistency */ - if (! rc) - goto sbrk_exit; -#ifdef TRACE - printf ("Decommit %p %d\n", base_committed, decommit_size); -#endif - } - /* Adjust deallocation size and regions commit and allocate top */ - deallocate_size -= (char *) g_last->top_allocated - (char *) base_committed; - g_last->top_committed = base_committed; - g_last->top_allocated = base_committed; - } - } - /* Adjust regions allocate top */ - g_last->top_allocated = (char *) g_last->top_allocated - deallocate_size; - /* Check for underflow */ - if ((char *) g_last->top_reserved - g_last->reserve_size > (char *) g_last->top_allocated || - g_last->top_allocated > g_last->top_committed) { - /* Adjust regions allocate top */ - g_last->top_allocated = (char *) g_last->top_reserved - g_last->reserve_size; - goto sbrk_exit; - } - result = g_last->top_allocated; - } - /* Assert invariants */ - assert (g_last); - assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated && - g_last->top_allocated <= g_last->top_committed); - assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed && - g_last->top_committed <= g_last->top_reserved && - (unsigned) g_last->top_committed % g_pagesize == 0); - assert ((unsigned) g_last->top_reserved % g_regionsize == 0); - assert ((unsigned) g_last->reserve_size % g_regionsize == 0); - -sbrk_exit: -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Release spin lock */ - slrelease (&g_sl); -#endif - return result; -} - -/* mmap for windows */ -static void *mmap (void *ptr, long size, long prot, long type, long handle, long arg) { - static long g_pagesize; - static long g_regionsize; -#ifdef TRACE - printf ("mmap %d\n", size); -#endif -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Wait for spin lock */ - slwait (&g_sl); -#endif - /* First time initialization */ - if (! g_pagesize) - g_pagesize = getpagesize (); - if (! g_regionsize) - g_regionsize = getregionsize (); - /* Assert preconditions */ - assert ((unsigned) ptr % g_regionsize == 0); - assert (size % g_pagesize == 0); - /* Allocate this */ - ptr = VirtualAlloc (ptr, size, - MEM_RESERVE | MEM_COMMIT | MEM_TOP_DOWN, PAGE_READWRITE); - if (! ptr) { - ptr = (void *) MORECORE_FAILURE; - goto mmap_exit; - } - /* Assert postconditions */ - assert ((unsigned) ptr % g_regionsize == 0); -#ifdef TRACE - printf ("Commit %p %d\n", ptr, size); -#endif -mmap_exit: -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Release spin lock */ - slrelease (&g_sl); -#endif - return ptr; -} - -/* munmap for windows */ -static long munmap (void *ptr, long size) { - static long g_pagesize; - static long g_regionsize; - int rc = MUNMAP_FAILURE; -#ifdef TRACE - printf ("munmap %p %d\n", ptr, size); -#endif -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Wait for spin lock */ - slwait (&g_sl); -#endif - /* First time initialization */ - if (! g_pagesize) - g_pagesize = getpagesize (); - if (! g_regionsize) - g_regionsize = getregionsize (); - /* Assert preconditions */ - assert ((unsigned) ptr % g_regionsize == 0); - assert (size % g_pagesize == 0); - /* Free this */ - if (! VirtualFree (ptr, 0, - MEM_RELEASE)) - goto munmap_exit; - rc = 0; -#ifdef TRACE - printf ("Release %p %d\n", ptr, size); -#endif -munmap_exit: -#if defined (USE_MALLOC_LOCK) && defined (NEEDED) - /* Release spin lock */ - slrelease (&g_sl); -#endif - return rc; -} - -static void vminfo (CHUNK_SIZE_T *free, CHUNK_SIZE_T *reserved, CHUNK_SIZE_T *committed) { - MEMORY_BASIC_INFORMATION memory_info; - memory_info.BaseAddress = 0; - *free = *reserved = *committed = 0; - while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) { - switch (memory_info.State) { - case MEM_FREE: - *free += memory_info.RegionSize; - break; - case MEM_RESERVE: - *reserved += memory_info.RegionSize; - break; - case MEM_COMMIT: - *committed += memory_info.RegionSize; - break; - } - memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize; - } -} - -static int cpuinfo (int whole, CHUNK_SIZE_T *kernel, CHUNK_SIZE_T *user) { - if (whole) { - __int64 creation64, exit64, kernel64, user64; - int rc = GetProcessTimes (GetCurrentProcess (), - (FILETIME *) &creation64, - (FILETIME *) &exit64, - (FILETIME *) &kernel64, - (FILETIME *) &user64); - if (! rc) { - *kernel = 0; - *user = 0; - return FALSE; - } - *kernel = (CHUNK_SIZE_T) (kernel64 / 10000); - *user = (CHUNK_SIZE_T) (user64 / 10000); - return TRUE; - } else { - __int64 creation64, exit64, kernel64, user64; - int rc = GetThreadTimes (GetCurrentThread (), - (FILETIME *) &creation64, - (FILETIME *) &exit64, - (FILETIME *) &kernel64, - (FILETIME *) &user64); - if (! rc) { - *kernel = 0; - *user = 0; - return FALSE; - } - *kernel = (CHUNK_SIZE_T) (kernel64 / 10000); - *user = (CHUNK_SIZE_T) (user64 / 10000); - return TRUE; - } -} - -#endif /* WIN32 */ - -/* ------------------------------------------------------------ -History: - V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee) - * Fix malloc_state bitmap array misdeclaration - - V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee) - * Allow tuning of FIRST_SORTED_BIN_SIZE - * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte. - * Better detection and support for non-contiguousness of MORECORE. - Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger - * Bypass most of malloc if no frees. Thanks To Emery Berger. - * Fix freeing of old top non-contiguous chunk im sysmalloc. - * Raised default trim and map thresholds to 256K. - * Fix mmap-related #defines. Thanks to Lubos Lunak. - * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield. - * Branch-free bin calculation - * Default trim and mmap thresholds now 256K. - - V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee) - * Introduce independent_comalloc and independent_calloc. - Thanks to Michael Pachos for motivation and help. - * Make optional .h file available - * Allow > 2GB requests on 32bit systems. - * new WIN32 sbrk, mmap, munmap, lock code from <Walter@xxxxxxxxxxxx>. - Thanks also to Andreas Mueller <a.mueller at paradatec.de>, - and Anonymous. - * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for - helping test this.) - * memalign: check alignment arg - * realloc: don't try to shift chunks backwards, since this - leads to more fragmentation in some programs and doesn't - seem to help in any others. - * Collect all cases in malloc requiring system memory into sYSMALLOc - * Use mmap as backup to sbrk - * Place all internal state in malloc_state - * Introduce fastbins (although similar to 2.5.1) - * Many minor tunings and cosmetic improvements - * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK - * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS - Thanks to Tony E. Bennett <tbennett@xxxxxxxxxx> and others. - * Include errno.h to support default failure action. - - V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee) - * return null for negative arguments - * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com> - * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h' - (e.g. WIN32 platforms) - * Cleanup header file inclusion for WIN32 platforms - * Cleanup code to avoid Microsoft Visual C++ compiler complaints - * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing - memory allocation routines - * Set 'malloc_getpagesize' for WIN32 platforms (needs more work) - * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to - usage of 'assert' in non-WIN32 code - * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to - avoid infinite loop - * Always call 'fREe()' rather than 'free()' - - V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee) - * Fixed ordering problem with boundary-stamping - - V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) - * Added pvalloc, as recommended by H.J. Liu - * Added 64bit pointer support mainly from Wolfram Gloger - * Added anonymously donated WIN32 sbrk emulation - * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen - * malloc_extend_top: fix mask error that caused wastage after - foreign sbrks - * Add linux mremap support code from HJ Liu - - V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) - * Integrated most documentation with the code. - * Add support for mmap, with help from - Wolfram Gloger (Gloger@xxxxxxxxxxxxxxxxxxx). - * Use last_remainder in more cases. - * Pack bins using idea from colin@xxxxxxxxxxxxxxx - * Use ordered bins instead of best-fit threshhold - * Eliminate block-local decls to simplify tracing and debugging. - * Support another case of realloc via move into top - * Fix error occuring when initial sbrk_base not word-aligned. - * Rely on page size for units instead of SBRK_UNIT to - avoid surprises about sbrk alignment conventions. - * Add mallinfo, mallopt. Thanks to Raymond Nijssen - (raymond@xxxxxxxxxxxxx) for the suggestion. - * Add `pad' argument to malloc_trim and top_pad mallopt parameter. - * More precautions for cases where other routines call sbrk, - courtesy of Wolfram Gloger (Gloger@xxxxxxxxxxxxxxxxxxx). - * Added macros etc., allowing use in linux libc from - H.J. Lu (hjl@xxxxxxxxxxxxxx) - * Inverted this history list - - V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) - * Re-tuned and fixed to behave more nicely with V2.6.0 changes. - * Removed all preallocation code since under current scheme - the work required to undo bad preallocations exceeds - the work saved in good cases for most test programs. - * No longer use return list or unconsolidated bins since - no scheme using them consistently outperforms those that don't - given above changes. - * Use best fit for very large chunks to prevent some worst-cases. - * Added some support for debugging - - V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) - * Removed footers when chunks are in use. Thanks to - Paul Wilson (wilson@xxxxxxxxxxxx) for the suggestion. - - V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) - * Added malloc_trim, with help from Wolfram Gloger - (wmglo@xxxxxxxxxxxxxxxxxxxxxxxx). - - V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) - - V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) - * realloc: try to expand in both directions - * malloc: swap order of clean-bin strategy; - * realloc: only conditionally expand backwards - * Try not to scavenge used bins - * Use bin counts as a guide to preallocation - * Occasionally bin return list chunks in first scan - * Add a few optimizations from colin@xxxxxxxxxxxxxxx - - V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) - * faster bin computation & slightly different binning - * merged all consolidations to one part of malloc proper - (eliminating old malloc_find_space & malloc_clean_bin) - * Scan 2 returns chunks (not just 1) - * Propagate failure in realloc if malloc returns 0 - * Add stuff to allow compilation on non-ANSI compilers - from kpv@xxxxxxxxxxxxxxxx - - V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) - * removed potential for odd address access in prev_chunk - * removed dependency on getpagesize.h - * misc cosmetics and a bit more internal documentation - * anticosmetics: mangled names in macros to evade debugger strangeness - * tested on sparc, hp-700, dec-mips, rs6000 - with gcc & native cc (hp, dec only) allowing - Detlefs & Zorn comparison study (in SIGPLAN Notices.) - - Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) - * Based loosely on libg++-1.2X malloc. (It retains some of the overall - structure of old version, but most details differ.) - -*/ _______________________________________________ Xen-changelog mailing list Xen-changelog@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-changelog

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