/*
* lib/hexdump.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. See README and COPYING for
* more details.
*/
#include <linux/types.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
#include <linux/module.h>
/**
* hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
* @buf: data blob to dump
* @len: number of bytes in the @buf
* @linebuf: where to put the converted data
* @linebuflen: total size of @linebuf, including space for terminating NUL
*
* hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
* 16 bytes of input data converted to hex + ASCII output.
*
* Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
* to a hex + ASCII dump at the supplied memory location.
* The converted output is always NUL-terminated.
*
* E.g.:
* hex_dump_to_buffer(frame->data, frame->len, linebuf, sizeof(linebuf));
*
* example output buffer:
* 40414243 44454647 48494a4b 4c4d4e4f @ABCDEFGHIJKLMNO
*/
void hex_dump_to_buffer(const void *buf, size_t len, char *linebuf,
size_t linebuflen)
{
const u8 *ptr = buf;
u8 ch;
int j, lx = 0;
for (j = 0; (j < 16) && (j < len) && (lx + 3) < linebuflen; j++) {
if (j && !(j % 4))
linebuf[lx++] = ' ';
ch = ptr[j];
linebuf[lx++] = hex_asc(ch >> 4);
linebuf[lx++] = hex_asc(ch & 0x0f);
}
if ((lx + 2) < linebuflen) {
linebuf[lx++] = ' ';
linebuf[lx++] = ' ';
}
for (j = 0; (j < 16) && (j < len) && (lx + 2) < linebuflen; j++)
linebuf[lx++] = isprint(ptr[j]) ? ptr[j] : '.';
linebuf[lx++] = '\0';
}
EXPORT_SYMBOL(hex_dump_to_buffer);
/**
* print_hex_dump - print a text hex dump to syslog for a binary blob of data
* @level: kernel log level (e.g. KERN_DEBUG)
* @prefix_type: controls whether prefix of an offset, address, or none
* is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
* @buf: data blob to dump
* @len: number of bytes in the @buf
*
* Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
* to the kernel log at the specified kernel log level, with an optional
* leading prefix.
*
* E.g.:
* print_hex_dump(KERN_DEBUG, DUMP_PREFIX_ADDRESS, frame->data, frame->len);
*
* Example output using %DUMP_PREFIX_OFFSET:
* 0009ab42: 40414243 44454647 48494a4b 4c4d4e4f @ABCDEFGHIJKLMNO
* Example output using %DUMP_PREFIX_ADDRESS:
* ffffffff88089af0: 70717273 74757677 78797a7b 7c7d7e7f pqrstuvwxyz{|}~.
*/
void print_hex_dump(const char *level, int prefix_type, void *buf, size_t len)
{
u8 *ptr = buf;
int i, linelen, remaining = len;
unsigned char linebuf[100];
for (i = 0; i < len; i += 16) {
linelen = min(remaining, 16);
remaining -= 16;
hex_dump_to_buffer(ptr + i, linelen, linebuf, sizeof(linebuf));
switch (prefix_type) {
case DUMP_PREFIX_ADDRESS:
printk("%s%*p: %s\n", level,
(int)(2 * sizeof(void *)), ptr + i, linebuf);
break;
case DUMP_PREFIX_OFFSET:
printk("%s%.8x: %s\n", level, i, linebuf);
break;
default:
printk("%s%s\n", level, linebuf);
break;
}
}
}
EXPORT_SYMBOL(print_hex_dump);
