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 #include <getopt.h>
  21
  22 #include "volumes.h"
  23 #include "crc32c.h"
  24 #include "commands.h"
  25 #include "utils.h"
  26 #include "help.h"
  27
  28 static const char * const btrfs_cmd_group_usage[] = {
  29         "btrfs [--help] [--version] <group> [<group>...] <command> [<args>]",
  30         NULL
  31 };
  32
  33 static const char btrfs_cmd_group_info[] =
  34         "Use --help as an argument for information on a specific group or command.";
  35
  36 static inline const char *skip_prefix(const char *str, const char *prefix)
  37 {
  38         size_t len = strlen(prefix);
  39         return strncmp(str, prefix, len) ? NULL : str + len;
  40 }
  41
  42 static int parse_one_token(const char *arg, const struct cmd_group *grp,
  43                            const struct cmd_struct **cmd_ret)
  44 {
  45         const struct cmd_struct *cmd = grp->commands;
  46         const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL;
  47
  48         for (; cmd->token; cmd++) {
  49                 const char *rest;
  50
  51                 rest = skip_prefix(arg, cmd->token);
  52                 if (!rest) {
  53                         if (!prefixcmp(cmd->token, arg)) {
  54                                 if (abbrev_cmd) {
  55                                         /*
  56                                          * If this is abbreviated, it is
  57                                          * ambiguous. So when there is no
  58                                          * exact match later, we need to
  59                                          * error out.
  60                                          */
  61                                         ambiguous_cmd = abbrev_cmd;
  62                                 }
  63                                 abbrev_cmd = cmd;
  64                         }
  65                         continue;
  66                 }
  67                 if (*rest)
  68                         continue;
  69
  70                 *cmd_ret = cmd;
  71                 return 0;
  72         }
  73
  74         if (ambiguous_cmd)
  75                 return -2;
  76
  77         if (abbrev_cmd) {
  78                 *cmd_ret = abbrev_cmd;
  79                 return 0;
  80         }
  81
  82         return -1;
  83 }
  84
  85 static const struct cmd_struct *
  86 parse_command_token(const char *arg, const struct cmd_group *grp)
  87 {
  88         const struct cmd_struct *cmd = NULL;
  89
  90         switch(parse_one_token(arg, grp, &cmd)) {
  91         case -1:
  92                 help_unknown_token(arg, grp);
  93         case -2:
  94                 help_ambiguous_token(arg, grp);
  95         }
  96
  97         return cmd;
  98 }
  99
 100 static void handle_help_options_next_level(const struct cmd_struct *cmd,
 101                 int argc, char **argv)
 102 {
 103         if (argc < 2)
 104                 return;
 105
 106         if (!strcmp(argv[1], "--help")) {
 107                 if (cmd->next) {
 108                         argc--;
 109                         argv++;
 110                         help_command_group(cmd->next, argc, argv);
 111                 } else {
 112                         usage_command(cmd, 1, 0);
 113                 }
 114
 115                 exit(0);
 116         }
 117 }
 118
 119 int handle_command_group(const struct cmd_group *grp, int argc,
 120                          char **argv)
 121
 122 {
 123         const struct cmd_struct *cmd;
 124
 125         argc--;
 126         argv++;
 127         if (argc < 1) {
 128                 usage_command_group(grp, 0, 0);
 129                 exit(1);
 130         }
 131
 132         cmd = parse_command_token(argv[0], grp);
 133
 134         handle_help_options_next_level(cmd, argc, argv);
 135
 136         fixup_argv0(argv, cmd->token);
 137         return cmd->fn(argc, argv);
 138 }
 139
 140 static const struct cmd_group btrfs_cmd_group;
 141
 142 static const char * const cmd_help_usage[] = {
 143         "btrfs help [--full]",
 144         "Display help information",
 145         "",
 146         "--full     display detailed help on every command",
 147         NULL
 148 };
 149
 150 static int cmd_help(int argc, char **argv)
 151 {
 152         help_command_group(&btrfs_cmd_group, argc, argv);
 153         return 0;
 154 }
 155
 156 static const char * const cmd_version_usage[] = {
 157         "btrfs version",
 158         "Display btrfs-progs version",
 159         NULL
 160 };
 161
 162 static int cmd_version(int argc, char **argv)
 163 {
 164         printf("%s\n", PACKAGE_STRING);
 165         return 0;
 166 }
 167
 168 /*
 169  * Parse global options, between binary name and first non-option argument
 170  * after processing all valid options (including those with arguments).
 171  *
 172  * Returns index to argv where parsting stopped, optind is reset to 1
 173  */
 174 static int handle_global_options(int argc, char **argv)
 175 {
 176         enum { OPT_HELP = 256, OPT_VERSION, OPT_FULL };
 177         static const struct option long_options[] = {
 178                 { "help", no_argument, NULL, OPT_HELP },
 179                 { "version", no_argument, NULL, OPT_VERSION },
 180                 { "full", no_argument, NULL, OPT_FULL },
 181                 { NULL, 0, NULL, 0}
 182         };
 183         int shift;
 184
 185         if (argc == 0)
 186                 return 0;
 187
 188         opterr = 0;
 189         while (1) {
 190                 int c;
 191
 192                 c = getopt_long(argc, argv, "+", long_options, NULL);
 193                 if (c < 0)
 194                         break;
 195
 196                 switch (c) {
 197                 case OPT_HELP: break;
 198                 case OPT_VERSION: break;
 199                 case OPT_FULL: break;
 200                 default:
 201                         fprintf(stderr, "Unknown global option: %s\n",
 202                                         argv[optind - 1]);
 203                         exit(129);
 204                 }
 205         }
 206
 207         shift = optind;
 208         optind = 1;
 209
 210         return shift;
 211 }
 212
 213 void handle_special_globals(int shift, int argc, char **argv)
 214 {
 215         int has_help = 0;
 216         int has_full = 0;
 217         int i;
 218
 219         for (i = 0; i < shift; i++) {
 220                 if (strcmp(argv[i], "--help") == 0)
 221                         has_help = 1;
 222                 else if (strcmp(argv[i], "--full") == 0)
 223                         has_full = 1;
 224         }
 225
 226         if (has_help) {
 227                 if (has_full)
 228                         usage_command_group(&btrfs_cmd_group, 1, 0);
 229                 else
 230                         cmd_help(argc, argv);
 231                 exit(0);
 232         }
 233
 234         for (i = 0; i < shift; i++)
 235                 if (strcmp(argv[i], "--version") == 0) {
 236                         cmd_version(argc, argv);
 237                         exit(0);
 238                 }
 239 }
 240
 241 static const struct cmd_group btrfs_cmd_group = {
 242         btrfs_cmd_group_usage, btrfs_cmd_group_info, {
 243                 { "subvolume", cmd_subvolume, NULL, &subvolume_cmd_group, 0 },
 244                 { "filesystem", cmd_filesystem, NULL, &filesystem_cmd_group, 0 },
 245                 { "balance", cmd_balance, NULL, &balance_cmd_group, 0 },
 246                 { "device", cmd_device, NULL, &device_cmd_group, 0 },
 247                 { "scrub", cmd_scrub, NULL, &scrub_cmd_group, 0 },
 248                 { "check", cmd_check, cmd_check_usage, NULL, 0 },
 249                 { "rescue", cmd_rescue, NULL, &rescue_cmd_group, 0 },
 250                 { "restore", cmd_restore, cmd_restore_usage, NULL, 0 },
 251                 { "inspect-internal", cmd_inspect, NULL, &inspect_cmd_group, 0 },
 252                 { "property", cmd_property, NULL, &property_cmd_group, 0 },
 253                 { "send", cmd_send, cmd_send_usage, NULL, 0 },
 254                 { "receive", cmd_receive, cmd_receive_usage, NULL, 0 },
 255                 { "quota", cmd_quota, NULL, &quota_cmd_group, 0 },
 256                 { "qgroup", cmd_qgroup, NULL, &qgroup_cmd_group, 0 },
 257                 { "replace", cmd_replace, NULL, &replace_cmd_group, 0 },
 258                 { "help", cmd_help, cmd_help_usage, NULL, 0 },
 259                 { "version", cmd_version, cmd_version_usage, NULL, 0 },
 260                 NULL_CMD_STRUCT
 261         },
 262 };
 263
 264 int main(int argc, char **argv)
 265 {
 266         const struct cmd_struct *cmd;
 267         const char *bname;
 268         int ret;
 269
 270         btrfs_config_init();
 271
 272         if ((bname = strrchr(argv[0], '/')) != NULL)
 273                 bname++;
 274         else
 275                 bname = argv[0];
 276
 277         if (!strcmp(bname, "btrfsck")) {
 278                 argv[0] = "check";
 279         } else {
 280                 int shift;
 281
 282                 shift = handle_global_options(argc, argv);
 283                 handle_special_globals(shift, argc, argv);
 284                 while (shift-- > 0) {
 285                         argc--;
 286                         argv++;
 287                 }
 288                 if (argc == 0) {
 289                         usage_command_group_short(&btrfs_cmd_group);
 290                         exit(1);
 291                 }
 292         }
 293
 294         cmd = parse_command_token(argv[0], &btrfs_cmd_group);
 295
 296         handle_help_options_next_level(cmd, argc, argv);
 297
 298         crc32c_optimization_init();
 299
 300         fixup_argv0(argv, cmd->token);
 301
 302         ret = cmd->fn(argc, argv);
 303
 304         btrfs_close_all_devices();
 305
 306         exit(ret);
 307 }