/* * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #define _GNU_SOURCE #include #include #include #include "commands.h" #include "version.h" static const char btrfs_cmd_group_usage[] = "btrfs [--help] [--version] [...] []"; static const char btrfs_cmd_group_info[] = "Use --help as an argument for information on a specific group or command."; char argv0_buf[ARGV0_BUF_SIZE] = "btrfs"; static inline const char *skip_prefix(const char *str, const char *prefix) { size_t len = strlen(prefix); return strncmp(str, prefix, len) ? NULL : str + len; } int prefixcmp(const char *str, const char *prefix) { for (; ; str++, prefix++) if (!*prefix) return 0; else if (*str != *prefix) return (unsigned char)*prefix - (unsigned char)*str; } static int parse_one_token(const char *arg, const struct cmd_group *grp, const struct cmd_struct **cmd_ret) { const struct cmd_struct *cmd = grp->commands; const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL; for (; cmd->token; cmd++) { const char *rest; rest = skip_prefix(arg, cmd->token); if (!rest) { if (!prefixcmp(cmd->token, arg)) { if (abbrev_cmd) { /* * If this is abbreviated, it is * ambiguous. So when there is no * exact match later, we need to * error out. */ ambiguous_cmd = abbrev_cmd; } abbrev_cmd = cmd; } continue; } if (*rest) continue; *cmd_ret = cmd; return 0; } if (ambiguous_cmd) return -2; if (abbrev_cmd) { *cmd_ret = abbrev_cmd; return 0; } return -1; } static const struct cmd_struct * parse_command_token(const char *arg, const struct cmd_group *grp) { const struct cmd_struct *cmd; switch(parse_one_token(arg, grp, &cmd)) { case -1: help_unknown_token(arg, grp); case -2: help_ambiguous_token(arg, grp); } return cmd; } void handle_help_options_next_level(const struct cmd_struct *cmd, int argc, char **argv) { if (argc < 2) return; if (!strcmp(argv[1], "--help")) { if (cmd->next) { argc--; argv++; help_command_group(cmd->next, argc, argv); } else { usage_command(cmd, 1, 0); } exit(0); } } static void fixup_argv0(char **argv, const char *token) { int len = strlen(argv0_buf); snprintf(argv0_buf + len, sizeof(argv0_buf) - len, " %s", token); argv[0] = argv0_buf; } int handle_command_group(const struct cmd_group *grp, int argc, char **argv) { const struct cmd_struct *cmd; argc--; argv++; if (argc < 1) { usage_command_group(grp, 0, 0); exit(1); } cmd = parse_command_token(argv[0], grp); handle_help_options_next_level(cmd, argc, argv); fixup_argv0(argv, cmd->token); return cmd->fn(argc, argv); } int check_argc_exact(int nargs, int expected) { if (nargs < expected) fprintf(stderr, "%s: too few arguments\n", argv0_buf); if (nargs > expected) fprintf(stderr, "%s: too many arguments\n", argv0_buf); return nargs != expected; } int check_argc_min(int nargs, int expected) { if (nargs < expected) { fprintf(stderr, "%s: too few arguments\n", argv0_buf); return 1; } return 0; } int check_argc_max(int nargs, int expected) { if (nargs > expected) { fprintf(stderr, "%s: too many arguments\n", argv0_buf); return 1; } return 0; } const struct cmd_group btrfs_cmd_group; static const char * const cmd_help_usage[] = { "btrfs help [--full]", "Dislay help information", "", "--full display detailed help on every command", NULL }; static int cmd_help(int argc, char **argv) { help_command_group(&btrfs_cmd_group, argc, argv); return 0; } static const char * const cmd_version_usage[] = { "btrfs version", "Display btrfs-progs version", NULL }; static int cmd_version(int argc, char **argv) { printf("%s\n", BTRFS_BUILD_VERSION); return 0; } static int handle_options(int *argc, char ***argv) { char **orig_argv = *argv; while (*argc > 0) { const char *arg = (*argv)[0]; if (arg[0] != '-') break; if (!strcmp(arg, "--help")) { break; } else if (!strcmp(arg, "--version")) { break; } else { fprintf(stderr, "Unknown option: %s\n", arg); fprintf(stderr, "usage: %s\n", btrfs_cmd_group.usagestr); exit(129); } (*argv)++; (*argc)--; } return (*argv) - orig_argv; } const struct cmd_group btrfs_cmd_group = { btrfs_cmd_group_usage, btrfs_cmd_group_info, { { "help", cmd_help, cmd_help_usage, NULL, 0 }, { "version", cmd_version, cmd_version_usage, NULL, 0 }, { 0, 0, 0, 0, 0 } }, }; int main(int argc, char **argv) { const struct cmd_struct *cmd; argc--; argv++; handle_options(&argc, &argv); if (argc > 0) { if (!prefixcmp(argv[0], "--")) argv[0] += 2; } else { usage_command_group(&btrfs_cmd_group, 0, 0); exit(1); } cmd = parse_command_token(argv[0], &btrfs_cmd_group); handle_help_options_next_level(cmd, argc, argv); fixup_argv0(argv, cmd->token); exit(cmd->fn(argc, argv)); }