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 "version.h"
  24 #include "utils.h"
  25
  26 static const char * const btrfs_cmd_group_usage[] = {
  27         "btrfs [--help] [--version] <group> [<group>...] <command> [<args>]",
  28         NULL
  29 };
  30
  31 static const char btrfs_cmd_group_info[] =
  32         "Use --help as an argument for information on a specific group or command.";
  33
  34 static inline const char *skip_prefix(const char *str, const char *prefix)
  35 {
  36         size_t len = strlen(prefix);
  37         return strncmp(str, prefix, len) ? NULL : str + len;
  38 }
  39
  40 int prefixcmp(const char *str, const char *prefix)
  41 {
  42         for (; ; str++, prefix++)
  43                 if (!*prefix)
  44                         return 0;
  45                 else if (*str != *prefix)
  46                         return (unsigned char)*prefix - (unsigned char)*str;
  47 }
  48
  49 static int parse_one_token(const char *arg, const struct cmd_group *grp,
  50                            const struct cmd_struct **cmd_ret)
  51 {
  52         const struct cmd_struct *cmd = grp->commands;
  53         const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL;
  54
  55         for (; cmd->token; cmd++) {
  56                 const char *rest;
  57
  58                 rest = skip_prefix(arg, cmd->token);
  59                 if (!rest) {
  60                         if (!prefixcmp(cmd->token, arg)) {
  61                                 if (abbrev_cmd) {
  62                                         /*
  63                                          * If this is abbreviated, it is
  64                                          * ambiguous. So when there is no
  65                                          * exact match later, we need to
  66                                          * error out.
  67                                          */
  68                                         ambiguous_cmd = abbrev_cmd;
  69                                 }
  70                                 abbrev_cmd = cmd;
  71                         }
  72                         continue;
  73                 }
  74                 if (*rest)
  75                         continue;
  76
  77                 *cmd_ret = cmd;
  78                 return 0;
  79         }
  80
  81         if (ambiguous_cmd)
  82                 return -2;
  83
  84         if (abbrev_cmd) {
  85                 *cmd_ret = abbrev_cmd;
  86                 return 0;
  87         }
  88
  89         return -1;
  90 }
  91
  92 static const struct cmd_struct *
  93 parse_command_token(const char *arg, const struct cmd_group *grp)
  94 {
  95         const struct cmd_struct *cmd = NULL;
  96
  97         switch(parse_one_token(arg, grp, &cmd)) {
  98         case -1:
  99                 help_unknown_token(arg, grp);
 100         case -2:
 101                 help_ambiguous_token(arg, grp);
 102         }
 103
 104         return cmd;
 105 }
 106
 107 static void handle_help_options_next_level(const struct cmd_struct *cmd,
 108                 int argc, char **argv)
 109 {
 110         if (argc < 2)
 111                 return;
 112
 113         if (!strcmp(argv[1], "--help")) {
 114                 if (cmd->next) {
 115                         argc--;
 116                         argv++;
 117                         help_command_group(cmd->next, argc, argv);
 118                 } else {
 119                         usage_command(cmd, 1, 0);
 120                 }
 121
 122                 exit(0);
 123         }
 124 }
 125
 126 int handle_command_group(const struct cmd_group *grp, int argc,
 127                          char **argv)
 128
 129 {
 130         const struct cmd_struct *cmd;
 131
 132         argc--;
 133         argv++;
 134         if (argc < 1) {
 135                 usage_command_group(grp, 0, 0);
 136                 exit(1);
 137         }
 138
 139         cmd = parse_command_token(argv[0], grp);
 140
 141         handle_help_options_next_level(cmd, argc, argv);
 142
 143         fixup_argv0(argv, cmd->token);
 144         return cmd->fn(argc, argv);
 145 }
 146
 147 static const struct cmd_group btrfs_cmd_group;
 148
 149 static const char * const cmd_help_usage[] = {
 150         "btrfs help [--full]",
 151         "Display help information",
 152         "",
 153         "--full     display detailed help on every command",
 154         NULL
 155 };
 156
 157 static int cmd_help(int argc, char **argv)
 158 {
 159         help_command_group(&btrfs_cmd_group, argc, argv);
 160         return 0;
 161 }
 162
 163 static const char * const cmd_version_usage[] = {
 164         "btrfs version",
 165         "Display btrfs-progs version",
 166         NULL
 167 };
 168
 169 static int cmd_version(int argc, char **argv)
 170 {
 171         printf("%s\n", BTRFS_BUILD_VERSION);
 172         return 0;
 173 }
 174
 175 static void handle_options(int *argc, char ***argv)
 176 {
 177         if (*argc > 0) {
 178                 const char *arg = (*argv)[0];
 179                 if (arg[0] != '-' ||
 180                     !strcmp(arg, "--help") ||
 181                     !strcmp(arg, "--version"))
 182                         return;
 183                 fprintf(stderr, "Unknown option: %s\n", arg);
 184                 fprintf(stderr, "usage: %s\n",
 185                         btrfs_cmd_group.usagestr[0]);
 186                 exit(129);
 187         }
 188         return;
 189 }
 190
 191 static const struct cmd_group btrfs_cmd_group = {
 192         btrfs_cmd_group_usage, btrfs_cmd_group_info, {
 193                 { "subvolume", cmd_subvolume, NULL, &subvolume_cmd_group, 0 },
 194                 { "filesystem", cmd_filesystem, NULL, &filesystem_cmd_group, 0 },
 195                 { "balance", cmd_balance, NULL, &balance_cmd_group, 0 },
 196                 { "device", cmd_device, NULL, &device_cmd_group, 0 },
 197                 { "scrub", cmd_scrub, NULL, &scrub_cmd_group, 0 },
 198                 { "check", cmd_check, cmd_check_usage, NULL, 0 },
 199                 { "rescue", cmd_rescue, NULL, &rescue_cmd_group, 0 },
 200                 { "restore", cmd_restore, cmd_restore_usage, NULL, 0 },
 201                 { "inspect-internal", cmd_inspect, NULL, &inspect_cmd_group, 0 },
 202                 { "property", cmd_property, NULL, &property_cmd_group, 0 },
 203                 { "send", cmd_send, cmd_send_usage, NULL, 0 },
 204                 { "receive", cmd_receive, cmd_receive_usage, NULL, 0 },
 205                 { "quota", cmd_quota, NULL, &quota_cmd_group, 0 },
 206                 { "qgroup", cmd_qgroup, NULL, &qgroup_cmd_group, 0 },
 207                 { "replace", cmd_replace, NULL, &replace_cmd_group, 0 },
 208                 { "help", cmd_help, cmd_help_usage, NULL, 0 },
 209                 { "version", cmd_version, cmd_version_usage, NULL, 0 },
 210                 NULL_CMD_STRUCT
 211         },
 212 };
 213
 214 int main(int argc, char **argv)
 215 {
 216         const struct cmd_struct *cmd;
 217         const char *bname;
 218
 219         if ((bname = strrchr(argv[0], '/')) != NULL)
 220                 bname++;
 221         else
 222                 bname = argv[0];
 223
 224         if (!strcmp(bname, "btrfsck")) {
 225                 argv[0] = "check";
 226         } else {
 227                 argc--;
 228                 argv++;
 229                 handle_options(&argc, &argv);
 230                 if (argc > 0) {
 231                         if (!prefixcmp(argv[0], "--"))
 232                                 argv[0] += 2;
 233                 } else {
 234                         usage_command_group(&btrfs_cmd_group, 0, 0);
 235                         exit(1);
 236                 }
 237         }
 238
 239         cmd = parse_command_token(argv[0], &btrfs_cmd_group);
 240
 241         handle_help_options_next_level(cmd, argc, argv);
 242
 243         crc32c_optimization_init();
 244
 245         fixup_argv0(argv, cmd->token);
 246         exit(cmd->fn(argc, argv));
 247 }