qemu/util/hexdump.c
Richard Henderson 10e4927bc4 util/hexdump: Inline g_string_append_printf "%02x"
Trivial arithmetic can be used for emitting the nibbles,
rather than full-blown printf formatting.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20240412073346.458116-6-richard.henderson@linaro.org>
2024-06-05 12:14:20 -07:00

100 lines
2.5 KiB
C

/*
* Helper to hexdump a buffer
*
* Copyright (c) 2013 Red Hat, Inc.
* Copyright (c) 2013 Gerd Hoffmann <kraxel@redhat.com>
* Copyright (c) 2013 Peter Crosthwaite <peter.crosthwaite@xilinx.com>
* Copyright (c) 2013 Xilinx, Inc
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qemu/cutils.h"
static inline char hexdump_nibble(unsigned x)
{
return (x < 10 ? '0' : 'a' - 10) + x;
}
GString *qemu_hexdump_line(GString *str, const void *vbuf, size_t len,
size_t unit_len, size_t block_len)
{
const uint8_t *buf = vbuf;
size_t u, b;
if (str == NULL) {
/* Estimate the length of the output to avoid reallocs. */
size_t est = len * 2;
if (unit_len) {
est += len / unit_len;
}
if (block_len) {
est += len / block_len;
}
str = g_string_sized_new(est + 1);
}
for (u = 0, b = 0; len; u++, b++, len--, buf++) {
uint8_t c;
if (unit_len && u == unit_len) {
g_string_append_c(str, ' ');
u = 0;
}
if (block_len && b == block_len) {
g_string_append_c(str, ' ');
b = 0;
}
c = *buf;
g_string_append_c(str, hexdump_nibble(c / 16));
g_string_append_c(str, hexdump_nibble(c % 16));
}
return str;
}
static void asciidump_line(char *line, const void *bufptr, size_t len)
{
const char *buf = bufptr;
for (size_t i = 0; i < len; i++) {
char c = buf[i];
if (c < ' ' || c > '~') {
c = '.';
}
*line++ = c;
}
*line = '\0';
}
#define QEMU_HEXDUMP_LINE_BYTES 16
#define QEMU_HEXDUMP_LINE_WIDTH \
(QEMU_HEXDUMP_LINE_BYTES * 2 + QEMU_HEXDUMP_LINE_BYTES / 4)
void qemu_hexdump(FILE *fp, const char *prefix,
const void *bufptr, size_t size)
{
g_autoptr(GString) str = g_string_sized_new(QEMU_HEXDUMP_LINE_WIDTH + 1);
char ascii[QEMU_HEXDUMP_LINE_BYTES + 1];
size_t b, len;
for (b = 0; b < size; b += len) {
len = MIN(size - b, QEMU_HEXDUMP_LINE_BYTES);
g_string_truncate(str, 0);
qemu_hexdump_line(str, bufptr + b, len, 1, 4);
asciidump_line(ascii, bufptr + b, len);
fprintf(fp, "%s: %04zx: %-*s %s\n",
prefix, b, QEMU_HEXDUMP_LINE_WIDTH, str->str, ascii);
}
}