diff options
Diffstat (limited to 'debugfs/zap.c')
| -rw-r--r-- | debugfs/zap.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/debugfs/zap.c b/debugfs/zap.c new file mode 100644 index 0000000..f862482 --- /dev/null +++ b/debugfs/zap.c @@ -0,0 +1,246 @@ +/* + * zap.c --- zap block + * + * Copyright (C) 2012 Theodore Ts'o. This file may be redistributed + * under the terms of the GNU Public License. + */ + +#include "config.h" +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <ctype.h> +#include <string.h> +#include <time.h> +#ifdef HAVE_ERRNO_H +#include <errno.h> +#endif +#include <sys/types.h> +#ifdef HAVE_GETOPT_H +#include <getopt.h> +#else +extern int optind; +extern char *optarg; +#endif + +#include "debugfs.h" + +void do_zap_block(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)), + void *infop EXT2FS_ATTR((unused))) +{ + unsigned long pattern = 0; + unsigned char *buf; + ext2_ino_t inode; + errcode_t errcode; + blk64_t block; + char *file = NULL; + int c, err; + int offset = -1; + int length = -1; + int bit = -1; + + if (check_fs_open(argv[0])) + return; + if (check_fs_read_write(argv[0])) + return; + + reset_getopt(); + while ((c = getopt (argc, argv, "b:f:l:o:p:")) != EOF) { + switch (c) { + case 'f': + file = optarg; + break; + case 'b': + bit = parse_ulong(optarg, argv[0], + "bit", &err); + if (err) + return; + if (bit >= (int) current_fs->blocksize * 8) { + com_err(argv[0], 0, "The bit to flip " + "must be within a %d block\n", + current_fs->blocksize); + return; + } + break; + case 'p': + pattern = parse_ulong(optarg, argv[0], + "pattern", &err); + if (err) + return; + if (pattern >= 256) { + com_err(argv[0], 0, "The fill pattern must " + "be an 8-bit value\n"); + return; + } + break; + case 'o': + offset = parse_ulong(optarg, argv[0], + "offset", &err); + if (err) + return; + if (offset >= (int) current_fs->blocksize) { + com_err(argv[0], 0, "The offset must be " + "within a %d block\n", + current_fs->blocksize); + return; + } + break; + + break; + case 'l': + length = parse_ulong(optarg, argv[0], + "length", &err); + if (err) + return; + break; + default: + goto print_usage; + } + } + + if (bit > 0 && offset > 0) { + com_err(argv[0], 0, "The -o and -b options can not be mixed."); + return; + } + + if (offset < 0) + offset = 0; + if (length < 0) + length = current_fs->blocksize - offset; + if ((offset + length) > (int) current_fs->blocksize) { + com_err(argv[0], 0, "The specified length is too bug\n"); + return; + } + + if (argc != optind+1) { + print_usage: + com_err(0, 0, "Usage:\tzap_block [-f file] [-o offset] " + "[-l length] [-p pattern] block_num"); + com_err(0, 0, "\tzap_block [-f file] [-b bit] " + "block_num"); + return; + } + + block = parse_ulonglong(argv[optind], argv[0], "block", &err); + if (err) + return; + + if (file) { + inode = string_to_inode(file); + if (!inode) + return; + errcode = ext2fs_bmap2(current_fs, inode, 0, 0, 0, + block, 0, &block); + if (errcode) { + com_err(argv[0], errcode, + "while mapping logical block %llu\n", + (unsigned long long) block); + return; + } + } + + buf = malloc(current_fs->blocksize); + if (!buf) { + com_err(argv[0], 0, "Couldn't allocate block buffer"); + return; + } + + errcode = io_channel_read_blk64(current_fs->io, block, 1, buf); + if (errcode) { + com_err(argv[0], errcode, + "while reading block %llu\n", + (unsigned long long) block); + goto errout; + } + + if (bit >= 0) + buf[bit >> 3] ^= 1 << (bit & 7); + else + memset(buf+offset, pattern, length); + + errcode = io_channel_write_blk64(current_fs->io, block, 1, buf); + if (errcode) { + com_err(argv[0], errcode, + "while write block %llu\n", + (unsigned long long) block); + goto errout; + } + +errout: + free(buf); + return; +} + +void do_block_dump(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)), + void *infop EXT2FS_ATTR((unused))) +{ + unsigned char *buf; + ext2_ino_t inode; + errcode_t errcode; + blk64_t block; + char *file = NULL; + int xattr_dump = 0; + int c, err; + + if (check_fs_open(argv[0])) + return; + + reset_getopt(); + while ((c = getopt (argc, argv, "f:x")) != EOF) { + switch (c) { + case 'f': + file = optarg; + break; + case 'x': + xattr_dump = 1; + break; + default: + goto print_usage; + } + } + + if (argc != optind + 1) { + print_usage: + com_err(0, 0, "Usage: block_dump [-x] [-f inode] block_num"); + return; + } + + block = parse_ulonglong(argv[optind], argv[0], "block", &err); + if (err) + return; + + if (file) { + inode = string_to_inode(file); + if (!inode) + return; + errcode = ext2fs_bmap2(current_fs, inode, 0, 0, 0, + block, 0, &block); + if (errcode) { + com_err(argv[0], errcode, + "while mapping logical block %llu\n", + (unsigned long long) block); + return; + } + } + + buf = malloc(current_fs->blocksize); + if (!buf) { + com_err(argv[0], 0, "Couldn't allocate block buffer"); + return; + } + + errcode = io_channel_read_blk64(current_fs->io, block, 1, buf); + if (errcode) { + com_err(argv[0], errcode, + "while reading block %llu\n", + (unsigned long long) block); + goto errout; + } + + if (xattr_dump) + block_xattr_dump(stdout, buf, current_fs->blocksize); + else + do_byte_hexdump(stdout, buf, current_fs->blocksize); +errout: + free(buf); +} |