Commit 99eaf3c4 authored by Randy Dunlap's avatar Randy Dunlap Committed by Linus Torvalds
Browse files

lib/hexdump 



Based on ace_dump_mem() from Grant Likely for the Xilinx SystemACE
CompactFlash interface.

Add print_hex_dump() & hex_dumper() to lib/hexdump.c and linux/kernel.h.

This patch adds the functions print_hex_dump() & hex_dumper().
print_hex_dump() can be used to perform a hex + ASCII dump of data to
syslog, in an easily viewable format, thus providing a common text hex dump
format.

hex_dumper() provides a dump-to-memory function.  It converts one "line" of
output (16 bytes of input) at a time.

Example usages:
	print_hex_dump(KERN_DEBUG, DUMP_PREFIX_ADDRESS, frame->data, frame->len);
	hex_dumper(frame->data, frame->len, linebuf, sizeof(linebuf));

Example output using %DUMP_PREFIX_OFFSET:
0009ab42: 40414243 44454647 48494a4b 4c4d4e4f-@ABCDEFG HIJKLMNO
Example output using %DUMP_PREFIX_ADDRESS:
ffffffff88089af0: 70717273 74757677 78797a7b 7c7d7e7f-pqrstuvw xyz{|}~.

[akpm@linux-foundation.org: cleanups, add export]
Signed-off-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6eaeeaba

include/linux/kernel.h

+11 −0
Original line number Diff line number Diff line
@@ -213,6 +213,17 @@ extern enum system_states { 


extern void dump_stack(void);



enum {

	DUMP_PREFIX_NONE,

	DUMP_PREFIX_ADDRESS,

	DUMP_PREFIX_OFFSET

};

extern void hex_dump_to_buffer(const void *buf, size_t len, char *linebuf,

				size_t linebuflen);

extern void print_hex_dump(const char *level, int prefix_type,

				void *buf, size_t len);

#define hex_asc(x)	"0123456789abcdef"[x]



#ifdef DEBUG

/* If you are writing a driver, please use dev_dbg instead */

#define pr_debug(fmt,arg...) \

lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ lib-$(CONFIG_SMP) += cpumask.o 
lib-y	+= kobject.o kref.o kobject_uevent.o klist.o



obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \

	 bust_spinlocks.o

	 bust_spinlocks.o hexdump.o



ifeq ($(CONFIG_DEBUG_KOBJECT),y)

CFLAGS_kobject.o += -DDEBUG

lib/hexdump.c

0 → 100644
+104 −0
Original line number Diff line number Diff line 
/*

 * 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);

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