blob: 0485e82ce5e08b29fb1eb00bc65c73e557200cc8
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * tune2fs: utility to modify EXT2 filesystem |
4 | * |
5 | * Busybox'ed (2009) by Vladimir Dronnikov <dronnikov@gmail.com> |
6 | * |
7 | * Licensed under GPLv2, see file LICENSE in this source tree. |
8 | */ |
9 | //config:config TUNE2FS |
10 | //config: bool "tune2fs" |
11 | //config: default n # off: it is too limited compared to upstream version |
12 | //config: help |
13 | //config: tune2fs allows the system administrator to adjust various tunable |
14 | //config: filesystem parameters on Linux ext2/ext3 filesystems. |
15 | |
16 | //applet:IF_TUNE2FS(APPLET(tune2fs, BB_DIR_SBIN, BB_SUID_DROP)) |
17 | |
18 | //TODO alias to "tune2fs -L LABEL": //applet:IF_E2LABEL(APPLET_ODDNAME(e2label, tune2fs, BB_DIR_SBIN, BB_SUID_DROP, e2label)) |
19 | |
20 | //kbuild:lib-$(CONFIG_TUNE2FS) += tune2fs.o |
21 | |
22 | //usage:#define tune2fs_trivial_usage |
23 | //usage: "[-c MAX_MOUNT_COUNT] " |
24 | ////usage: "[-e errors-behavior] [-g group] " |
25 | //usage: "[-i DAYS] " |
26 | ////usage: "[-j] [-J journal-options] [-l] [-s sparse-flag] " |
27 | ////usage: "[-m reserved-blocks-percent] [-o [^]mount-options[,...]] " |
28 | ////usage: "[-r reserved-blocks-count] [-u user] " |
29 | //usage: "[-C MOUNT_COUNT] " |
30 | //usage: "[-L LABEL] " |
31 | ////usage: "[-M last-mounted-dir] [-O [^]feature[,...]] " |
32 | ////usage: "[-T last-check-time] [-U UUID] " |
33 | //usage: "BLOCKDEV" |
34 | //usage: |
35 | //usage:#define tune2fs_full_usage "\n\n" |
36 | //usage: "Adjust filesystem options on ext[23] filesystems" |
37 | |
38 | #include "libbb.h" |
39 | #include <linux/fs.h> |
40 | #include "bb_e2fs_defs.h" |
41 | |
42 | // storage helpers |
43 | char BUG_wrong_field_size(void); |
44 | #define STORE_LE(field, value) \ |
45 | do { \ |
46 | if (sizeof(field) == 4) \ |
47 | field = SWAP_LE32(value); \ |
48 | else if (sizeof(field) == 2) \ |
49 | field = SWAP_LE16(value); \ |
50 | else if (sizeof(field) == 1) \ |
51 | field = (value); \ |
52 | else \ |
53 | BUG_wrong_field_size(); \ |
54 | } while (0) |
55 | |
56 | #define FETCH_LE32(field) \ |
57 | (sizeof(field) == 4 ? SWAP_LE32(field) : BUG_wrong_field_size()) |
58 | |
59 | enum { |
60 | OPT_L = 1 << 0, // label |
61 | OPT_c = 1 << 1, // max mount count |
62 | OPT_i = 1 << 2, // check interval |
63 | OPT_C = 1 << 3, // current mount count |
64 | }; |
65 | |
66 | int tune2fs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
67 | int tune2fs_main(int argc UNUSED_PARAM, char **argv) |
68 | { |
69 | unsigned opts; |
70 | const char *label, *str_c, *str_i, *str_C; |
71 | struct ext2_super_block *sb; |
72 | int fd; |
73 | |
74 | opt_complementary = "=1"; |
75 | opts = getopt32(argv, "L:c:i:C:", &label, &str_c, &str_i, &str_C); |
76 | if (!opts) |
77 | bb_show_usage(); |
78 | argv += optind; // argv[0] -- device |
79 | |
80 | // read superblock |
81 | fd = xopen(argv[0], O_RDWR); |
82 | xlseek(fd, 1024, SEEK_SET); |
83 | sb = xzalloc(1024); |
84 | xread(fd, sb, 1024); |
85 | |
86 | // mangle superblock |
87 | //STORE_LE(sb->s_wtime, time(NULL)); - why bother? |
88 | |
89 | if (opts & OPT_C) { |
90 | int n = xatoi_range(str_C, 1, 0xfffe); |
91 | if (n == 0) n = 1; |
92 | STORE_LE(sb->s_mnt_count, (unsigned)n); |
93 | } |
94 | |
95 | // set the label |
96 | if (opts & OPT_L) |
97 | safe_strncpy((char *)sb->s_volume_name, label, sizeof(sb->s_volume_name)); |
98 | |
99 | if (opts & OPT_c) { |
100 | int n = xatoi_range(str_c, -1, 0xfffe); |
101 | if (n == 0) |
102 | n = -1; |
103 | STORE_LE(sb->s_max_mnt_count, (unsigned)n); |
104 | } |
105 | |
106 | if (opts & OPT_i) { |
107 | unsigned n = xatou_range(str_i, 0, (unsigned)0xffffffff / (24*60*60)) * 24*60*60; |
108 | STORE_LE(sb->s_checkinterval, n); |
109 | } |
110 | |
111 | // write superblock |
112 | xlseek(fd, 1024, SEEK_SET); |
113 | xwrite(fd, sb, 1024); |
114 | |
115 | if (ENABLE_FEATURE_CLEAN_UP) { |
116 | free(sb); |
117 | } |
118 | |
119 | xclose(fd); |
120 | return EXIT_SUCCESS; |
121 | } |
122 |