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(&btrfs_cmd_group, 0, 0);
 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 }