diff options
| -rw-r--r-- | include/linux/kernel.h | 11 | ||||
| -rw-r--r-- | lib/Makefile | 2 | ||||
| -rw-r--r-- | lib/hexdump.c | 104 |
3 files changed, 116 insertions, 1 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 8645181..eec0d13 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -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...) \ diff --git a/lib/Makefile b/lib/Makefile index 1f65b46..c8c8e20 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -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 diff --git a/lib/hexdump.c b/lib/hexdump.c new file mode 100644 index 0000000..e6da5b7 --- /dev/null +++ b/lib/hexdump.c @@ -0,0 +1,104 @@ +/* + * 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); |