support for ubifs overlay
[project/fstools.git] / snapshot.c
1 /*
2 * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU Lesser General Public License version 2.1
6 * as published by the Free Software Foundation
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14 #include <sys/stat.h>
15 #include <sys/stat.h>
16 #include <sys/types.h>
17 #include <sys/ioctl.h>
18 #include <sys/mount.h>
19 #include <mtd/mtd-user.h>
20
21 #include <glob.h>
22 #include <fcntl.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <libgen.h>
26 #include <unistd.h>
27 #include <string.h>
28
29 #include <libubox/list.h>
30 #include <libubox/blob.h>
31 #include <libubox/md5.h>
32
33 #include "libfstools/libfstools.h"
34 #include "libfstools/volume.h"
35 #include "libfstools/snapshot.h"
36
37 static int
38 config_write(int argc, char **argv)
39 {
40 struct volume *v = volume_find("rootfs_data");
41 int ret;
42
43 if (!v)
44 return -1;
45
46 ret = volatile_write(v, 0);
47 if (!ret)
48 ret = sentinel_write(v, 0);
49
50 return ret;
51 }
52
53 static int
54 config_read(int argc, char **argv)
55 {
56 struct volume *v = volume_find("rootfs_data");
57 struct file_header conf, sentinel;
58 int next, block, ret = 0;
59 uint32_t seq;
60
61 if (!v)
62 return -1;
63
64 block = config_find(v, &conf, &sentinel);
65 next = snapshot_next_free(v, &seq);
66 if (is_config(&conf) && conf.seq == seq)
67 block = next;
68 else if (!is_config(&sentinel) || sentinel.seq != seq)
69 return -1;
70
71 unlink("/tmp/config.tar.gz");
72 ret = snapshot_read_file(v, block, "/tmp/config.tar.gz", CONF);
73
74 if (ret < 1)
75 fprintf(stderr, "failed to read /tmp/config.tar.gz\n");
76
77 return ret;
78 }
79
80 static int
81 snapshot_write(int argc, char **argv)
82 {
83 struct volume *v = volume_find("rootfs_data");
84 int block, ret;
85 uint32_t seq;
86
87 if (!v)
88 return -1;
89
90 block = snapshot_next_free(v, &seq);
91 if (block < 0)
92 block = 0;
93
94 ret = snapshot_write_file(v, block, "/tmp/snapshot.tar.gz", seq + 1, DATA);
95 if (ret)
96 fprintf(stderr, "failed to write /tmp/snapshot.tar.gz\n");
97 else
98 fprintf(stderr, "wrote /tmp/snapshot.tar.gz\n");
99
100 return ret;
101 }
102
103 static int
104 snapshot_mark(int argc, char **argv)
105 {
106 __be32 owrt = cpu_to_be32(OWRT);
107 struct volume *v;
108 size_t sz;
109 int fd;
110
111 fprintf(stderr, "This will remove all snapshot data stored on the system. Are you sure? [N/y]\n");
112 if (getchar() != 'y')
113 return -1;
114
115 v = volume_find("rootfs_data");
116 if (!v) {
117 fprintf(stderr, "no rootfs_data was found\n");
118 return -1;
119 }
120
121 fd = open(v->blk, O_WRONLY);
122 fprintf(stderr, "%s - marking with 0x%08x\n", v->blk, owrt);
123 if (fd < 0) {
124 fprintf(stderr, "opening %s failed\n", v->blk);
125 return -1;
126 }
127
128 sz = write(fd, &owrt, sizeof(owrt));
129 close(fd);
130
131 if (sz != 1) {
132 fprintf(stderr, "writing %s failed: %s\n", v->blk, strerror(errno));
133 return -1;
134 }
135
136 return 0;
137 }
138
139 static int
140 snapshot_read(int argc, char **argv)
141 {
142 struct volume *v = volume_find("rootfs_data");;
143 int block = 0, ret = 0;
144 char file[64];
145
146 if (!v)
147 return -1;
148
149 if (argc > 2) {
150 block = atoi(argv[2]);
151 if (block >= (v->size / v->block_size)) {
152 fprintf(stderr, "invalid block %d > %llu\n", block, v->size / v->block_size);
153 goto out;
154 }
155 snprintf(file, sizeof(file), "/tmp/snapshot/block%d.tar.gz", block);
156
157 ret = snapshot_read_file(v, block, file, DATA);
158 goto out;
159 }
160
161 do {
162 snprintf(file, sizeof(file), "/tmp/snapshot/block%d.tar.gz", block);
163 block = snapshot_read_file(v, block, file, DATA);
164 } while (block > 0);
165
166 out:
167 return ret;
168 }
169
170 static int
171 snapshot_info(void)
172 {
173 struct volume *v = volume_find("rootfs_data");
174 struct file_header hdr = { 0 }, conf;
175 int block = 0;
176
177 if (!v)
178 return -1;
179
180 fprintf(stderr, "sectors:\t%llu, block_size:\t%dK\n", v->size / v->block_size, v->block_size / 1024);
181 do {
182 if (volume_read(v, &hdr, block * v->block_size, sizeof(struct file_header))) {
183 fprintf(stderr, "scanning for next free block failed\n");
184 return 0;
185 }
186
187 be32_to_hdr(&hdr);
188
189 if (hdr.magic != OWRT)
190 break;
191
192 if (hdr.type == DATA)
193 fprintf(stderr, "block %d:\tsnapshot entry, size: %d, sectors: %d, sequence: %d\n", block, hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
194 else if (hdr.type == CONF)
195 fprintf(stderr, "block %d:\tvolatile entry, size: %d, sectors: %d, sequence: %d\n", block, hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
196
197 if (hdr.type == DATA && !valid_file_size(hdr.length))
198 block += pad_file_size(v, hdr.length) / v->block_size;
199 } while (hdr.type == DATA);
200 block = config_find(v, &conf, &hdr);
201 if (block > 0)
202 fprintf(stderr, "block %d:\tsentinel entry, size: %d, sectors: %d, sequence: %d\n", block, hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
203
204 return 0;
205 }
206
207 int main(int argc, char **argv)
208 {
209 if (argc < 2)
210 return -1;
211
212 if (!strcmp(argv[1], "config_read"))
213 return config_read(argc, argv);
214 if (!strcmp(argv[1], "config_write"))
215 return config_write(argc, argv);
216 if (!strcmp(argv[1], "read"))
217 return snapshot_read(argc, argv);
218 if (!strcmp(argv[1], "write"))
219 return snapshot_write(argc, argv);
220 if (!strcmp(argv[1], "mark"))
221 return snapshot_mark(argc, argv);
222 if (!strcmp(argv[1], "info"))
223 return snapshot_info();
224 return -1;
225 }