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 #define _GNU_SOURCE
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21
  22 #include "crc32c.h"
  23 #include "commands.h"
  24 #include "version.h"
  25 #include "utils.h"
  26
  27 static const char * const btrfs_cmd_group_usage[] = {
  28         "btrfs [--help] [--version] <group> [<group>...] <command> [<args>]",
  29         NULL
  30 };
  31
  32 static const char btrfs_cmd_group_info[] =
  33         "Use --help as an argument for information on a specific group or command.";
  34
  35 static inline const char *skip_prefix(const char *str, const char *prefix)
  36 {
  37         size_t len = strlen(prefix);
  38         return strncmp(str, prefix, len) ? NULL : str + len;
  39 }
  40
  41 int prefixcmp(const char *str, const char *prefix)
  42 {
  43         for (; ; str++, prefix++)
  44                 if (!*prefix)
  45                         return 0;
  46                 else if (*str != *prefix)
  47                         return (unsigned char)*prefix - (unsigned char)*str;
  48 }
  49
  50 static int parse_one_token(const char *arg, const struct cmd_group *grp,
  51                            const struct cmd_struct **cmd_ret)
  52 {
  53         const struct cmd_struct *cmd = grp->commands;
  54         const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL;
  55
  56         for (; cmd->token; cmd++) {
  57                 const char *rest;
  58
  59                 rest = skip_prefix(arg, cmd->token);
  60                 if (!rest) {
  61                         if (!prefixcmp(cmd->token, arg)) {
  62                                 if (abbrev_cmd) {
  63                                         /*
  64                                          * If this is abbreviated, it is
  65                                          * ambiguous. So when there is no
  66                                          * exact match later, we need to
  67                                          * error out.
  68                                          */
  69                                         ambiguous_cmd = abbrev_cmd;
  70                                 }
  71                                 abbrev_cmd = cmd;
  72                         }
  73                         continue;
  74                 }
  75                 if (*rest)
  76                         continue;
  77
  78                 *cmd_ret = cmd;
  79                 return 0;
  80         }
  81
  82         if (ambiguous_cmd)
  83                 return -2;
  84
  85         if (abbrev_cmd) {
  86                 *cmd_ret = abbrev_cmd;
  87                 return 0;
  88         }
  89
  90         return -1;
  91 }
  92
  93 static const struct cmd_struct *
  94 parse_command_token(const char *arg, const struct cmd_group *grp)
  95 {
  96         const struct cmd_struct *cmd = NULL;
  97
  98         switch(parse_one_token(arg, grp, &cmd)) {
  99         case -1:
 100                 help_unknown_token(arg, grp);
 101         case -2:
 102                 help_ambiguous_token(arg, grp);
 103         }
 104
 105         return cmd;
 106 }
 107
 108 static void handle_help_options_next_level(const struct cmd_struct *cmd,
 109                 int argc, char **argv)
 110 {
 111         if (argc < 2)
 112                 return;
 113
 114         if (!strcmp(argv[1], "--help")) {
 115                 if (cmd->next) {
 116                         argc--;
 117                         argv++;
 118                         help_command_group(cmd->next, argc, argv);
 119                 } else {
 120                         usage_command(cmd, 1, 0);
 121                 }
 122
 123                 exit(0);
 124         }
 125 }
 126
 127 int handle_command_group(const struct cmd_group *grp, int argc,
 128                          char **argv)
 129
 130 {
 131         const struct cmd_struct *cmd;
 132
 133         argc--;
 134         argv++;
 135         if (argc < 1) {
 136                 usage_command_group(grp, 0, 0);
 137                 exit(1);
 138         }
 139
 140         cmd = parse_command_token(argv[0], grp);
 141
 142         handle_help_options_next_level(cmd, argc, argv);
 143
 144         fixup_argv0(argv, cmd->token);
 145         return cmd->fn(argc, argv);
 146 }
 147
 148 static const struct cmd_group btrfs_cmd_group;
 149
 150 static const char * const cmd_help_usage[] = {
 151         "btrfs help [--full]",
 152         "Display help information",
 153         "",
 154         "--full     display detailed help on every command",
 155         NULL
 156 };
 157
 158 static int cmd_help(int argc, char **argv)
 159 {
 160         help_command_group(&btrfs_cmd_group, argc, argv);
 161         return 0;
 162 }
 163
 164 static const char * const cmd_version_usage[] = {
 165         "btrfs version",
 166         "Display btrfs-progs version",
 167         NULL
 168 };
 169
 170 static int cmd_version(int argc, char **argv)
 171 {
 172         printf("%s\n", BTRFS_BUILD_VERSION);
 173         return 0;
 174 }
 175
 176 static void handle_options(int *argc, char ***argv)
 177 {
 178         if (*argc > 0) {
 179                 const char *arg = (*argv)[0];
 180                 if (arg[0] != '-' ||
 181                     !strcmp(arg, "--help") ||
 182                     !strcmp(arg, "--version"))
 183                         return;
 184                 fprintf(stderr, "Unknown option: %s\n", arg);
 185                 fprintf(stderr, "usage: %s\n",
 186                         btrfs_cmd_group.usagestr[0]);
 187                 exit(129);
 188         }
 189         return;
 190 }
 191
 192 static const struct cmd_group btrfs_cmd_group = {
 193         btrfs_cmd_group_usage, btrfs_cmd_group_info, {
 194                 { "subvolume", cmd_subvolume, NULL, &subvolume_cmd_group, 0 },
 195                 { "filesystem", cmd_filesystem, NULL, &filesystem_cmd_group, 0 },
 196                 { "balance", cmd_balance, NULL, &balance_cmd_group, 0 },
 197                 { "device", cmd_device, NULL, &device_cmd_group, 0 },
 198                 { "scrub", cmd_scrub, NULL, &scrub_cmd_group, 0 },
 199                 { "check", cmd_check, cmd_check_usage, NULL, 0 },
 200                 { "rescue", cmd_rescue, NULL, &rescue_cmd_group, 0 },
 201                 { "restore", cmd_restore, cmd_restore_usage, NULL, 0 },
 202                 { "inspect-internal", cmd_inspect, NULL, &inspect_cmd_group, 0 },
 203                 { "property", cmd_property, NULL, &property_cmd_group, 0 },
 204                 { "send", cmd_send, cmd_send_usage, NULL, 0 },
 205                 { "receive", cmd_receive, cmd_receive_usage, NULL, 0 },
 206                 { "quota", cmd_quota, NULL, &quota_cmd_group, 0 },
 207                 { "qgroup", cmd_qgroup, NULL, &qgroup_cmd_group, 0 },
 208                 { "replace", cmd_replace, NULL, &replace_cmd_group, 0 },
 209                 { "help", cmd_help, cmd_help_usage, NULL, 0 },
 210                 { "version", cmd_version, cmd_version_usage, NULL, 0 },
 211                 NULL_CMD_STRUCT
 212         },
 213 };
 214
 215 int main(int argc, char **argv)
 216 {
 217         const struct cmd_struct *cmd;
 218         const char *bname;
 219
 220         if ((bname = strrchr(argv[0], '/')) != NULL)
 221                 bname++;
 222         else
 223                 bname = argv[0];
 224
 225         if (!strcmp(bname, "btrfsck")) {
 226                 argv[0] = "check";
 227         } else {
 228                 argc--;
 229                 argv++;
 230                 handle_options(&argc, &argv);
 231                 if (argc > 0) {
 232                         if (!prefixcmp(argv[0], "--"))
 233                                 argv[0] += 2;
 234                 } else {
 235                         usage_command_group(&btrfs_cmd_group, 0, 0);
 236                         exit(1);
 237                 }
 238         }
 239
 240         cmd = parse_command_token(argv[0], &btrfs_cmd_group);
 241
 242         handle_help_options_next_level(cmd, argc, argv);
 243
 244         crc32c_optimization_init();
 245
 246         fixup_argv0(argv, cmd->token);
 247         exit(cmd->fn(argc, argv));
 248 }