[PATCH 04/15] mini-os: replace multiple fd elements in struct file by common one

[Juergen Gross <jgross@xxxxxxxx>]

The type specific union in struct files contains two instances of
"int fd". Replace them by a common one.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 include/lib.h |  9 +--------
 lib/sys.c     | 28 ++++++++++++++--------------
 2 files changed, 15 insertions(+), 22 deletions(-)

diff --git a/include/lib.h b/include/lib.h
index 4d9b14b..dc56f52 100644
--- a/include/lib.h
+++ b/include/lib.h
@@ -187,14 +187,7 @@ struct file {
     bool read; /* maybe available for read */
     off_t offset;
     union {
-       struct {
-            /* lwIP fd */
-           int fd;
-       } socket;
-       struct {
-            /* FS import fd */
-           int fd;
-       } file;
+        int fd; /* Any fd from an upper layer. */
        struct {
            struct evtchn_port_list ports;
        } evtchn;
diff --git a/lib/sys.c b/lib/sys.c
index e1cea70..1da7401 100644
--- a/lib/sys.c
+++ b/lib/sys.c
@@ -258,7 +258,7 @@ int read(int fd, void *buf, size_t nbytes)
         }
 #ifdef HAVE_LWIP
        case FTYPE_SOCKET:
-           return lwip_read(files[fd].socket.fd, buf, nbytes);
+           return lwip_read(files[fd].fd, buf, nbytes);
 #endif
 #ifdef CONFIG_NETFRONT
        case FTYPE_TAP: {
@@ -335,7 +335,7 @@ int write(int fd, const void *buf, size_t nbytes)
            return nbytes;
 #ifdef HAVE_LWIP
        case FTYPE_SOCKET:
-           return lwip_write(files[fd].socket.fd, (void*) buf, nbytes);
+           return lwip_write(files[fd].fd, (void*) buf, nbytes);
 #endif
 #ifdef CONFIG_NETFRONT
        case FTYPE_TAP:
@@ -428,7 +428,7 @@ int close(int fd)
 #endif
 #ifdef HAVE_LWIP
        case FTYPE_SOCKET: {
-           int res = lwip_close(files[fd].socket.fd);
+           int res = lwip_close(files[fd].fd);
            files[fd].type = FTYPE_NONE;
            return res;
        }
@@ -594,7 +594,7 @@ int fcntl(int fd, int cmd, ...)
            if (files[fd].type == FTYPE_SOCKET && !(arg & ~O_NONBLOCK)) {
                /* Only flag supported: non-blocking mode */
                uint32_t nblock = !!(arg & O_NONBLOCK);
-               return lwip_ioctl(files[fd].socket.fd, FIONBIO, &nblock);
+               return lwip_ioctl(files[fd].fd, FIONBIO, &nblock);
            }
            /* Fallthrough */
 #endif
@@ -732,15 +732,15 @@ static int select_poll(int nfds, fd_set *readfds, fd_set 
*writefds, fd_set *exce
     for (i = 0; i < nfds; i++) {
        if (files[i].type == FTYPE_SOCKET) {
            if (FD_ISSET(i, readfds)) {
-               FD_SET(files[i].socket.fd, &sock_readfds);
+               FD_SET(files[i].fd, &sock_readfds);
                sock_nfds = i+1;
            }
            if (FD_ISSET(i, writefds)) {
-               FD_SET(files[i].socket.fd, &sock_writefds);
+               FD_SET(files[i].fd, &sock_writefds);
                sock_nfds = i+1;
            }
            if (FD_ISSET(i, exceptfds)) {
-               FD_SET(files[i].socket.fd, &sock_exceptfds);
+               FD_SET(files[i].fd, &sock_exceptfds);
                sock_nfds = i+1;
            }
        }
@@ -803,19 +803,19 @@ static int select_poll(int nfds, fd_set *readfds, fd_set 
*writefds, fd_set *exce
        case FTYPE_SOCKET:
            if (FD_ISSET(i, readfds)) {
                /* Optimize no-network-packet case.  */
-               if (sock_n && FD_ISSET(files[i].socket.fd, &sock_readfds))
+               if (sock_n && FD_ISSET(files[i].fd, &sock_readfds))
                    n++;
                else
                    FD_CLR(i, readfds);
            }
             if (FD_ISSET(i, writefds)) {
-               if (sock_n && FD_ISSET(files[i].socket.fd, &sock_writefds))
+               if (sock_n && FD_ISSET(files[i].fd, &sock_writefds))
                    n++;
                else
                    FD_CLR(i, writefds);
             }
             if (FD_ISSET(i, exceptfds)) {
-               if (sock_n && FD_ISSET(files[i].socket.fd, &sock_exceptfds))
+               if (sock_n && FD_ISSET(files[i].fd, &sock_exceptfds))
                    n++;
                else
                    FD_CLR(i, exceptfds);
@@ -1112,7 +1112,7 @@ int socket(int domain, int type, int protocol)
        return -1;
     res = alloc_fd(FTYPE_SOCKET);
     printk("socket -> %d\n", res);
-    files[res].socket.fd = fd;
+    files[res].fd = fd;
     return res;
 }
 
@@ -1124,11 +1124,11 @@ int accept(int s, struct sockaddr *addr, socklen_t 
*addrlen)
        errno = EBADF;
        return -1;
     }
-    fd = lwip_accept(files[s].socket.fd, addr, addrlen);
+    fd = lwip_accept(files[s].fd, addr, addrlen);
     if (fd < 0)
        return -1;
     res = alloc_fd(FTYPE_SOCKET);
-    files[res].socket.fd = fd;
+    files[res].fd = fd;
     printk("accepted on %d -> %d\n", s, res);
     return res;
 }
@@ -1141,7 +1141,7 @@ ret name proto \
        errno = EBADF; \
        return -1; \
     } \
-    s = files[s].socket.fd; \
+    s = files[s].fd; \
     return lwip_##name args; \
 }
 
-- 
2.26.2