Re: [Xen-devel] [PATCH v4 05/15] xenctx: Add command line option -D (--decode-as-ascii)

[George Dunlap <george.dunlap@xxxxxxxxxxxxx>]

On 03/18/2014 10:15 PM, Don Slutz wrote:
> If specified, output ascii version of stack also.
>
> Here is an example:
>
> Stack:
>   ffffffff80048d19 0000000000200800 ffffffff803e7801 0000000000086800  .......... 
> ......x>......h......
>   0000000000000000 ffffffff80430720 ffffffff803e722f 80008e000010019c  ........ 
> .C...../r>.............
>   00000000ffffffff 0000000000000000 0000000000000000 0000000000200000  
> .......................... .....
>   0000000000000000 0000000000000000                                    
> ................
>
> Signed-off-by: Don Slutz <Don@xxxxxxxxxxxxxxx>
> ---
>   tools/xentrace/xenctx.c | 35 ++++++++++++++++++++++++++++++++++-
>   1 file changed, 34 insertions(+), 1 deletion(-)
>
> diff --git a/tools/xentrace/xenctx.c b/tools/xentrace/xenctx.c
> index 62a8519..850e091 100644
> --- a/tools/xentrace/xenctx.c
> +++ b/tools/xentrace/xenctx.c
> @@ -38,6 +38,7 @@ static struct xenctx {
>       int multiple_pages;
>       int bytes_per_line;
>       int lines;
> +    int decode_as_ascii;
>       int all_vcpus;
>       int self_paused;
>       xc_dominfo_t dominfo;
> @@ -665,6 +666,7 @@ static int print_stack(vcpu_guest_context_any_t *ctx, int 
> vcpu, int width)
>       guest_word_t frame;
>       guest_word_t word;
>       guest_word_t *p;
> +    guest_word_t ascii[MAX_BYTES_PER_LINE/4];
>       int i;
>   
>       if ( width )
> @@ -679,6 +681,9 @@ static int print_stack(vcpu_guest_context_any_t *ctx, int 
> vcpu, int width)
>           printf("Stack:\n");
>           for (i = 1; i < xenctx.lines + 1 && stack < stack_limit; i++)
>           {
> +            int j = 0;
> +            int k;
> +
>               while ( stack < stack_limit &&
>                       stack < stack_pointer(ctx) + i * xenctx.bytes_per_line )
>               {
> @@ -686,10 +691,32 @@ static int print_stack(vcpu_guest_context_any_t *ctx, int 
> vcpu, int width)
>                   if ( !p )
>                       return -1;
>                   word = read_stack_word(p, width);
> +                if ( xenctx.decode_as_ascii )
> +                    ascii[j++] = word;
>                   printf(" ");
>                   print_stack_word(word, width);
>                   stack += width;
>               }
> +            printf("  ");
> +            if ( xenctx.decode_as_ascii )
> +            {
> +                for (k = j; k < xenctx.bytes_per_line / width; k++)
> +                    printf(" %*s", width*2, "");
It might be nice to have a comment here explaining what this is doing: 
maybe, "Line up ascii output if less than bytes_per_line were printed."
Also, the printf("  ") line above should probably go under this for 
loop.  It goes here logically, and it avoids printing trailing 
whitespace if decode_as_ascii is false.
 -George


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel