Re: [PATCH] Remove #define hex_asc from kernel.h, update lib/hexdump.c

Randy Dunlap
2007-11-29T18:26:29Z

On Thu, 29 Nov 2007 10:08:44 -0800 Joe Perches wrote:

> It's only use is in lib/hexdump.c
> Instead, use scnprintf in lib/hexdump.c
>
> Use "%0nx" not "%n.nx" (Smaller kernel, one byte at a time, woohoo!)
> Use true not 1 for print_hex_dump
> A bit of indentation style in lib/hexdump.c

I don't care for the mixed spaces/tabs.

> Size before/after
> text data bss dec hex filename
> 1037 0 0 1037 40d lib/hexdump.o
>
> text data bss dec hex filename
> 1019 0 0 1019 3fb lib/hexdump.o
>
> Signed-off-by: Joe Perches <joe@perches.com>
>
> ---
>
> include/linux/kernel.h | 1 -
> lib/hexdump.c | 23 ++++++++++-------------
> 2 files changed, 10 insertions(+), 14 deletions(-)
>
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 94bc996..77b187f 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -256,7 +256,6 @@ extern void print_hex_dump(const char *level, const char *prefix_str,
> const void *buf, size_t len, bool ascii);
> extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
> const void *buf, size_t len);
> -#define hex_asc(x) "0123456789abcdef"[x]
>
> #define pr_emerg(fmt, arg...) \
> printk(KERN_EMERG fmt, ##arg)
> diff --git a/lib/hexdump.c b/lib/hexdump.c
> index bd5edae..70e23fb 100644
> --- a/lib/hexdump.c
> +++ b/lib/hexdump.c
> @@ -41,7 +41,6 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
> bool ascii)
> {
> const u8 *ptr = buf;
> - u8 ch;
> int j, lx = 0;
> int ascii_column;
>
> @@ -62,7 +61,9 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
>
> for (j = 0; j < ngroups; j++)
> lx += scnprintf(linebuf + lx, linebuflen - lx,
> - "%16.16llx ", (unsigned long long)*(ptr8 + j));
> + "%016llx ",
> + (unsigned long long)*(ptr8 + j) &
> + 0xffffffffffffffffULL);
> ascii_column = 17 * ngroups + 2;
> break;
> }
> @@ -73,7 +74,7 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
>
> for (j = 0; j < ngroups; j++)
> lx += scnprintf(linebuf + lx, linebuflen - lx,
> - "%8.8x ", *(ptr4 + j));
> + "%08x ", *(ptr4 + j) & 0xffffffffU);
> ascii_column = 9 * ngroups + 2;
> break;
> }
> @@ -84,19 +85,15 @@ void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
>
> for (j = 0; j < ngroups; j++)
> lx += scnprintf(linebuf + lx, linebuflen - lx,
> - "%4.4x ", *(ptr2 + j));
> + "%04x ", *(ptr2 + j) & 0xffff);
> ascii_column = 5 * ngroups + 2;
> break;
> }
>
> default:
> - for (j = 0; (j < rowsize) && (j < len) && (lx + 4) < linebuflen;
> - j++) {
> - ch = ptr[j];
> - linebuf[lx++] = hex_asc(ch >> 4);
> - linebuf[lx++] = hex_asc(ch & 0x0f);
> - linebuf[lx++] = ' ';
> - }
> + for (j = 0; (j < rowsize) && (j < len) < linebuflen; j++)

What does
(j < len) < linebuflen;
do? I don't see that C construct very often.

> + lx += scnprintf(linebuf + lx, linebuflen - lx,
> + "%02x ", ptr[j] & 0xff);
> ascii_column = 3 * rowsize + 2;
> break;
> }
> @@ -163,7 +160,7 @@ void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
> switch (prefix_type) {
> case DUMP_PREFIX_ADDRESS:
> printk("%s%s%*p: %s\n", level, prefix_str,
> - (int)(2 * sizeof(void *)), ptr + i, linebuf);
> + (int)(2 * sizeof(void *)), ptr + i, linebuf);
> break;
> case DUMP_PREFIX_OFFSET:
> printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf);
> @@ -192,6 +189,6 @@ void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
> const void *buf, size_t len)
> {
> print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
> - buf, len, 1);
> + buf, len, true);
> }
> EXPORT_SYMBOL(print_hex_dump_bytes);

---
~Randy