summaryrefslogtreecommitdiff
path: root/difftool/sqfsdiff.c
blob: a065a8f8d75d749d60cde9f9651fdfac47449469 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * sqfsdiff.c
 *
 * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
 */
#include "difftool.h"

static struct option long_opts[] = {
	{ "old", required_argument, NULL, 'a' },
	{ "new", required_argument, NULL, 'b' },
	{ "no-owner", no_argument, NULL, 'O' },
	{ "no-permissions", no_argument, NULL, 'P' },
	{ "no-contents", no_argument, NULL, 'C' },
	{ "timestamps", no_argument, NULL, 'T' },
	{ "inode-num", no_argument, NULL, 'I' },
	{ "super", no_argument, NULL, 'S' },
	{ "extract", required_argument, NULL, 'e' },
	{ "help", no_argument, NULL, 'h' },
	{ "version", no_argument, NULL, 'V' },
};

static const char *short_opts = "a:b:OPCTISe:hV";

static const char *usagestr =
"Usage: sqfsdiff [OPTIONS...] --old,-a <first> --new,-b <second>\n"
"\n"
"Compare two squashfs images. In contrast to doing a direct diff of the\n"
"images, this actually parses the filesystems and generates a more\n"
"meaningful difference report.\n"
"\n"
"If only contents are compared, any differences in packed file layout,\n"
"ordering, compression, inode allocation and so on is ignored and the two\n"
"images are considered equal if each directory contains the same entries,\n"
"symlink with the same paths have the same targets, device nodes the same\n"
"device number and files the same size and contents.\n"
"\n"
"A report of any difference is printed to stdout. The exit status is similar\n"
"that of diff(1): 0 means equal, 1 means different, 2 means problem.\n"
"\n"
"Possible options:\n"
"\n"
"  --old, -a <first>           The first of the two images to compare.\n"
"  --new, -b <second>          The second of the two images to compare.\n"
"\n"
"  --no-contents, -C           Do not compare file contents.\n"
"  --no-owner, -O              Do not compare file owners.\n"
"  --no-permissions, -P        Do not compare permission bits.\n"
"\n"
"  --timestamps, -T            Compare file timestamps.\n"
"  --inode-num, -I             Compare inode numbers of all files.\n"
"  --super, -S                 Also compare metadata in super blocks.\n"
"\n"
"  --extract, -e <path>        Extract files that differ to the specified\n"
"                              directory. Contents of the first image end up\n"
"                              in a subdirectory 'a' and of the second image\n"
"                              in a subdirectory 'b'.\n"
"\n"
"  --help, -h                  Print help text and exit.\n"
"  --version, -V               Print version information and exit.\n"
"\n";

int compare_flags = 0;
const char *old_path;
const char *new_path;
sqfs_reader_t sqfs_old;
sqfs_reader_t sqfs_new;
bool old_is_dir;
bool new_is_dir;
static bool compare_super = false;
static const char *extract_dir;

static void process_options(int argc, char **argv)
{
	int i;

	for (;;) {
		i = getopt_long(argc, argv, short_opts, long_opts, NULL);
		if (i == -1)
			break;

		switch (i) {
		case 'a':
			old_path = optarg;
			break;
		case 'b':
			new_path = optarg;
			break;
		case 'O':
			compare_flags |= COMPARE_NO_OWNER;
			break;
		case 'P':
			compare_flags |= COMPARE_NO_PERM;
			break;
		case 'C':
			compare_flags |= COMPARE_NO_CONTENTS;
			break;
		case 'T':
			compare_flags |= COMPARE_TIMESTAMP;
			break;
		case 'I':
			compare_flags |= COMPARE_INODE_NUM;
			break;
		case 'S':
			compare_super = true;
			break;
		case 'e':
			compare_flags |= COMPARE_EXTRACT_FILES;
			extract_dir = optarg;
			break;
		case 'h':
			fputs(usagestr, stdout);
			exit(EXIT_SUCCESS);
		case 'V':
			print_version();
			exit(EXIT_SUCCESS);
		default:
			goto fail_arg;
		}
	}

	if (old_path == NULL) {
		fputs("Missing arguments: first filesystem\n", stderr);
		goto fail_arg;
	}

	if (new_path == NULL) {
		fputs("Missing arguments: second filesystem\n", stderr);
		goto fail_arg;
	}

	if (optind < argc) {
		fputs("Unknown extra arguments\n", stderr);
		goto fail_arg;
	}
	return;
fail_arg:
	fprintf(stderr, "Try `sqfsdiff --help' for more information.\n");
	exit(EXIT_FAILURE);
}

int main(int argc, char **argv)
{
	int status, ret = 0;

	process_options(argc, argv);

	if (extract_dir != NULL) {
		if (mkdir_p(extract_dir))
			return EXIT_FAILURE;
	}

	if (sqfs_reader_open(&sqfs_old, old_path, 0))
		return 2;

	if (sqfs_reader_open(&sqfs_new, new_path, 0)) {
		status = 2;
		goto out_sqfs_old;
	}

	if (extract_dir != NULL) {
		if (chdir(extract_dir)) {
			perror(extract_dir);
			ret = -1;
			goto out;
		}
	}

	ret = node_compare(sqfs_old.fs.root, sqfs_new.fs.root);
	if (ret != 0)
		goto out;

	if (compare_super) {
		ret = compare_super_blocks(&sqfs_old.super, &sqfs_new.super);
		if (ret != 0)
			goto out;
	}
out:
	if (ret < 0) {
		status = 2;
	} else if (ret > 0) {
		status = 1;
	} else {
		status = 0;
	}
	sqfs_reader_close(&sqfs_new);
out_sqfs_old:
	sqfs_reader_close(&sqfs_old);
	return status;
}