63df377a7ec8f32b71ddc68dc9798f4d67e924b6
[platform/upstream/btrfs-progs.git] / btrfs.c
1 /*
2  * This program is free software; you can redistribute it and/or
3  * modify it under the terms of the GNU General Public
4  * License v2 as published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
9  * General Public License for more details.
10  *
11  * You should have received a copy of the GNU General Public
12  * License along with this program; if not, write to the
13  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
14  * Boston, MA 021110-1307, USA.
15  */
16
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20
21 #include "crc32c.h"
22 #include "commands.h"
23 #include "utils.h"
24
25 static const char * const btrfs_cmd_group_usage[] = {
26         "btrfs [--help] [--version] <group> [<group>...] <command> [<args>]",
27         NULL
28 };
29
30 static const char btrfs_cmd_group_info[] =
31         "Use --help as an argument for information on a specific group or command.";
32
33 static inline const char *skip_prefix(const char *str, const char *prefix)
34 {
35         size_t len = strlen(prefix);
36         return strncmp(str, prefix, len) ? NULL : str + len;
37 }
38
39 int prefixcmp(const char *str, const char *prefix)
40 {
41         for (; ; str++, prefix++)
42                 if (!*prefix)
43                         return 0;
44                 else if (*str != *prefix)
45                         return (unsigned char)*prefix - (unsigned char)*str;
46 }
47
48 static int parse_one_token(const char *arg, const struct cmd_group *grp,
49                            const struct cmd_struct **cmd_ret)
50 {
51         const struct cmd_struct *cmd = grp->commands;
52         const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL;
53
54         for (; cmd->token; cmd++) {
55                 const char *rest;
56
57                 rest = skip_prefix(arg, cmd->token);
58                 if (!rest) {
59                         if (!prefixcmp(cmd->token, arg)) {
60                                 if (abbrev_cmd) {
61                                         /*
62                                          * If this is abbreviated, it is
63                                          * ambiguous. So when there is no
64                                          * exact match later, we need to
65                                          * error out.
66                                          */
67                                         ambiguous_cmd = abbrev_cmd;
68                                 }
69                                 abbrev_cmd = cmd;
70                         }
71                         continue;
72                 }
73                 if (*rest)
74                         continue;
75
76                 *cmd_ret = cmd;
77                 return 0;
78         }
79
80         if (ambiguous_cmd)
81                 return -2;
82
83         if (abbrev_cmd) {
84                 *cmd_ret = abbrev_cmd;
85                 return 0;
86         }
87
88         return -1;
89 }
90
91 static const struct cmd_struct *
92 parse_command_token(const char *arg, const struct cmd_group *grp)
93 {
94         const struct cmd_struct *cmd = NULL;
95
96         switch(parse_one_token(arg, grp, &cmd)) {
97         case -1:
98                 help_unknown_token(arg, grp);
99         case -2:
100                 help_ambiguous_token(arg, grp);
101         }
102
103         return cmd;
104 }
105
106 static void handle_help_options_next_level(const struct cmd_struct *cmd,
107                 int argc, char **argv)
108 {
109         if (argc < 2)
110                 return;
111
112         if (!strcmp(argv[1], "--help")) {
113                 if (cmd->next) {
114                         argc--;
115                         argv++;
116                         help_command_group(cmd->next, argc, argv);
117                 } else {
118                         usage_command(cmd, 1, 0);
119                 }
120
121                 exit(0);
122         }
123 }
124
125 int handle_command_group(const struct cmd_group *grp, int argc,
126                          char **argv)
127
128 {
129         const struct cmd_struct *cmd;
130
131         argc--;
132         argv++;
133         if (argc < 1) {
134                 usage_command_group(grp, 0, 0);
135                 exit(1);
136         }
137
138         cmd = parse_command_token(argv[0], grp);
139
140         handle_help_options_next_level(cmd, argc, argv);
141
142         fixup_argv0(argv, cmd->token);
143         return cmd->fn(argc, argv);
144 }
145
146 static const struct cmd_group btrfs_cmd_group;
147
148 static const char * const cmd_help_usage[] = {
149         "btrfs help [--full]",
150         "Display help information",
151         "",
152         "--full     display detailed help on every command",
153         NULL
154 };
155
156 static int cmd_help(int argc, char **argv)
157 {
158         help_command_group(&btrfs_cmd_group, argc, argv);
159         return 0;
160 }
161
162 static const char * const cmd_version_usage[] = {
163         "btrfs version",
164         "Display btrfs-progs version",
165         NULL
166 };
167
168 static int cmd_version(int argc, char **argv)
169 {
170         printf("%s\n", PACKAGE_STRING);
171         return 0;
172 }
173
174 static void handle_options(int *argc, char ***argv)
175 {
176         if (*argc > 0) {
177                 const char *arg = (*argv)[0];
178                 if (arg[0] != '-' ||
179                     !strcmp(arg, "--help") ||
180                     !strcmp(arg, "--version"))
181                         return;
182                 fprintf(stderr, "Unknown option: %s\n", arg);
183                 fprintf(stderr, "usage: %s\n",
184                         btrfs_cmd_group.usagestr[0]);
185                 exit(129);
186         }
187         return;
188 }
189
190 static const struct cmd_group btrfs_cmd_group = {
191         btrfs_cmd_group_usage, btrfs_cmd_group_info, {
192                 { "subvolume", cmd_subvolume, NULL, &subvolume_cmd_group, 0 },
193                 { "filesystem", cmd_filesystem, NULL, &filesystem_cmd_group, 0 },
194                 { "balance", cmd_balance, NULL, &balance_cmd_group, 0 },
195                 { "device", cmd_device, NULL, &device_cmd_group, 0 },
196                 { "scrub", cmd_scrub, NULL, &scrub_cmd_group, 0 },
197                 { "check", cmd_check, cmd_check_usage, NULL, 0 },
198                 { "rescue", cmd_rescue, NULL, &rescue_cmd_group, 0 },
199                 { "restore", cmd_restore, cmd_restore_usage, NULL, 0 },
200                 { "inspect-internal", cmd_inspect, NULL, &inspect_cmd_group, 0 },
201                 { "property", cmd_property, NULL, &property_cmd_group, 0 },
202                 { "send", cmd_send, cmd_send_usage, NULL, 0 },
203                 { "receive", cmd_receive, cmd_receive_usage, NULL, 0 },
204                 { "quota", cmd_quota, NULL, &quota_cmd_group, 0 },
205                 { "qgroup", cmd_qgroup, NULL, &qgroup_cmd_group, 0 },
206                 { "replace", cmd_replace, NULL, &replace_cmd_group, 0 },
207                 { "help", cmd_help, cmd_help_usage, NULL, 0 },
208                 { "version", cmd_version, cmd_version_usage, NULL, 0 },
209                 NULL_CMD_STRUCT
210         },
211 };
212
213 int main(int argc, char **argv)
214 {
215         const struct cmd_struct *cmd;
216         const char *bname;
217
218         if ((bname = strrchr(argv[0], '/')) != NULL)
219                 bname++;
220         else
221                 bname = argv[0];
222
223         if (!strcmp(bname, "btrfsck")) {
224                 argv[0] = "check";
225         } else {
226                 argc--;
227                 argv++;
228                 handle_options(&argc, &argv);
229                 if (argc > 0) {
230                         if (!prefixcmp(argv[0], "--"))
231                                 argv[0] += 2;
232                 } else {
233                         usage_command_group_short(&btrfs_cmd_group);
234                         exit(1);
235                 }
236         }
237
238         cmd = parse_command_token(argv[0], &btrfs_cmd_group);
239
240         handle_help_options_next_level(cmd, argc, argv);
241
242         crc32c_optimization_init();
243
244         fixup_argv0(argv, cmd->token);
245         exit(cmd->fn(argc, argv));
246 }