builtin/help.c

   1 /*
   2  * Builtin help command
   3  */
   4 #include "cache.h"
   5 #include "config.h"
   6 #include "builtin.h"
   7 #include "exec-cmd.h"
   8 #include "parse-options.h"
   9 #include "run-command.h"
  10 #include "config-list.h"
  11 #include "help.h"
  12 #include "alias.h"
  13
  14 #ifndef DEFAULT_HELP_FORMAT
  15 #define DEFAULT_HELP_FORMAT "man"
  16 #endif
  17
  18 static struct man_viewer_list {
  19         struct man_viewer_list *next;
  20         char name[FLEX_ARRAY];
  21 } *man_viewer_list;
  22
  23 static struct man_viewer_info_list {
  24         struct man_viewer_info_list *next;
  25         const char *info;
  26         char name[FLEX_ARRAY];
  27 } *man_viewer_info_list;
  28
  29 enum help_format {
  30         HELP_FORMAT_NONE,
  31         HELP_FORMAT_MAN,
  32         HELP_FORMAT_INFO,
  33         HELP_FORMAT_WEB
  34 };
  35
  36 enum show_config_type {
  37         SHOW_CONFIG_HUMAN,
  38         SHOW_CONFIG_VARS,
  39         SHOW_CONFIG_SECTIONS,
  40 };
  41
  42 static enum help_action {
  43         HELP_ACTION_ALL = 1,
  44         HELP_ACTION_GUIDES,
  45         HELP_ACTION_CONFIG,
  46         HELP_ACTION_CONFIG_FOR_COMPLETION,
  47         HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION,
  48 } cmd_mode;
  49
  50 static const char *html_path;
  51 static int verbose = 1;
  52 static enum help_format help_format = HELP_FORMAT_NONE;
  53 static int exclude_guides;
  54 static int show_external_commands = -1;
  55 static int show_aliases = -1;
  56 static struct option builtin_help_options[] = {
  57         OPT_CMDMODE('a', "all", &cmd_mode, N_("print all available commands"),
  58                     HELP_ACTION_ALL),
  59         OPT_BOOL(0, "external-commands", &show_external_commands,
  60                  N_("show external commands in --all")),
  61         OPT_BOOL(0, "aliases", &show_aliases, N_("show aliases in --all")),
  62         OPT_HIDDEN_BOOL(0, "exclude-guides", &exclude_guides, N_("exclude guides")),
  63         OPT_SET_INT('m', "man", &help_format, N_("show man page"), HELP_FORMAT_MAN),
  64         OPT_SET_INT('w', "web", &help_format, N_("show manual in web browser"),
  65                         HELP_FORMAT_WEB),
  66         OPT_SET_INT('i', "info", &help_format, N_("show info page"),
  67                         HELP_FORMAT_INFO),
  68         OPT__VERBOSE(&verbose, N_("print command description")),
  69
  70         OPT_CMDMODE('g', "guides", &cmd_mode, N_("print list of useful guides"),
  71                     HELP_ACTION_GUIDES),
  72         OPT_CMDMODE('c', "config", &cmd_mode, N_("print all configuration variable names"),
  73                     HELP_ACTION_CONFIG),
  74         OPT_CMDMODE_F(0, "config-for-completion", &cmd_mode, "",
  75                     HELP_ACTION_CONFIG_FOR_COMPLETION, PARSE_OPT_HIDDEN),
  76         OPT_CMDMODE_F(0, "config-sections-for-completion", &cmd_mode, "",
  77                     HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION, PARSE_OPT_HIDDEN),
  78
  79         OPT_END(),
  80 };
  81
  82 static const char * const builtin_help_usage[] = {
  83         "git help [-a|--all] [--[no-]verbose]] [--[no-]external-commands] [--[no-]aliases]",
  84         N_("git help [[-i|--info] [-m|--man] [-w|--web]] [<command>]"),
  85         "git help [-g|--guides]",
  86         "git help [-c|--config]",
  87         NULL
  88 };
  89
  90 struct slot_expansion {
  91         const char *prefix;
  92         const char *placeholder;
  93         void (*fn)(struct string_list *list, const char *prefix);
  94         int found;
  95 };
  96
  97 static void list_config_help(enum show_config_type type)
  98 {
  99         struct slot_expansion slot_expansions[] = {
 100                 { "advice", "*", list_config_advices },
 101                 { "color.branch", "<slot>", list_config_color_branch_slots },
 102                 { "color.decorate", "<slot>", list_config_color_decorate_slots },
 103                 { "color.diff", "<slot>", list_config_color_diff_slots },
 104                 { "color.grep", "<slot>", list_config_color_grep_slots },
 105                 { "color.interactive", "<slot>", list_config_color_interactive_slots },
 106                 { "color.remote", "<slot>", list_config_color_sideband_slots },
 107                 { "color.status", "<slot>", list_config_color_status_slots },
 108                 { "fsck", "<msg-id>", list_config_fsck_msg_ids },
 109                 { "receive.fsck", "<msg-id>", list_config_fsck_msg_ids },
 110                 { NULL, NULL, NULL }
 111         };
 112         const char **p;
 113         struct slot_expansion *e;
 114         struct string_list keys = STRING_LIST_INIT_DUP;
 115         struct string_list keys_uniq = STRING_LIST_INIT_DUP;
 116         struct string_list_item *item;
 117         int i;
 118
 119         for (p = config_name_list; *p; p++) {
 120                 const char *var = *p;
 121                 struct strbuf sb = STRBUF_INIT;
 122
 123                 for (e = slot_expansions; e->prefix; e++) {
 124
 125                         strbuf_reset(&sb);
 126                         strbuf_addf(&sb, "%s.%s", e->prefix, e->placeholder);
 127                         if (!strcasecmp(var, sb.buf)) {
 128                                 e->fn(&keys, e->prefix);
 129                                 e->found++;
 130                                 break;
 131                         }
 132                 }
 133                 strbuf_release(&sb);
 134                 if (!e->prefix)
 135                         string_list_append(&keys, var);
 136         }
 137
 138         for (e = slot_expansions; e->prefix; e++)
 139                 if (!e->found)
 140                         BUG("slot_expansion %s.%s is not used",
 141                             e->prefix, e->placeholder);
 142
 143         string_list_sort(&keys);
 144         for (i = 0; i < keys.nr; i++) {
 145                 const char *var = keys.items[i].string;
 146                 const char *wildcard, *tag, *cut;
 147                 const char *dot = NULL;
 148                 struct strbuf sb = STRBUF_INIT;
 149
 150                 switch (type) {
 151                 case SHOW_CONFIG_HUMAN:
 152                         puts(var);
 153                         continue;
 154                 case SHOW_CONFIG_SECTIONS:
 155                         dot = strchr(var, '.');
 156                         break;
 157                 case SHOW_CONFIG_VARS:
 158                         break;
 159                 }
 160                 wildcard = strchr(var, '*');
 161                 tag = strchr(var, '<');
 162
 163                 if (!dot && !wildcard && !tag) {
 164                         string_list_append(&keys_uniq, var);
 165                         continue;
 166                 }
 167
 168                 if (dot)
 169                         cut = dot;
 170                 else if (wildcard && !tag)
 171                         cut = wildcard;
 172                 else if (!wildcard && tag)
 173                         cut = tag;
 174                 else
 175                         cut = wildcard < tag ? wildcard : tag;
 176
 177                 strbuf_add(&sb, var, cut - var);
 178                 string_list_append(&keys_uniq, sb.buf);
 179                 strbuf_release(&sb);
 180
 181         }
 182         string_list_clear(&keys, 0);
 183         string_list_remove_duplicates(&keys_uniq, 0);
 184         for_each_string_list_item(item, &keys_uniq)
 185                 puts(item->string);
 186         string_list_clear(&keys_uniq, 0);
 187 }
 188
 189 static enum help_format parse_help_format(const char *format)
 190 {
 191         if (!strcmp(format, "man"))
 192                 return HELP_FORMAT_MAN;
 193         if (!strcmp(format, "info"))
 194                 return HELP_FORMAT_INFO;
 195         if (!strcmp(format, "web") || !strcmp(format, "html"))
 196                 return HELP_FORMAT_WEB;
 197         /*
 198          * Please update _git_config() in git-completion.bash when you
 199          * add new help formats.
 200          */
 201         die(_("unrecognized help format '%s'"), format);
 202 }
 203
 204 static const char *get_man_viewer_info(const char *name)
 205 {
 206         struct man_viewer_info_list *viewer;
 207
 208         for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
 209         {
 210                 if (!strcasecmp(name, viewer->name))
 211                         return viewer->info;
 212         }
 213         return NULL;
 214 }
 215
 216 static int check_emacsclient_version(void)
 217 {
 218         struct strbuf buffer = STRBUF_INIT;
 219         struct child_process ec_process = CHILD_PROCESS_INIT;
 220         int version;
 221
 222         /* emacsclient prints its version number on stderr */
 223         strvec_pushl(&ec_process.args, "emacsclient", "--version", NULL);
 224         ec_process.err = -1;
 225         ec_process.stdout_to_stderr = 1;
 226         if (start_command(&ec_process))
 227                 return error(_("Failed to start emacsclient."));
 228
 229         strbuf_read(&buffer, ec_process.err, 20);
 230         close(ec_process.err);
 231
 232         /*
 233          * Don't bother checking return value, because "emacsclient --version"
 234          * seems to always exits with code 1.
 235          */
 236         finish_command(&ec_process);
 237
 238         if (!starts_with(buffer.buf, "emacsclient")) {
 239                 strbuf_release(&buffer);
 240                 return error(_("Failed to parse emacsclient version."));
 241         }
 242
 243         strbuf_remove(&buffer, 0, strlen("emacsclient"));
 244         version = atoi(buffer.buf);
 245
 246         if (version < 22) {
 247                 strbuf_release(&buffer);
 248                 return error(_("emacsclient version '%d' too old (< 22)."),
 249                         version);
 250         }
 251
 252         strbuf_release(&buffer);
 253         return 0;
 254 }
 255
 256 static void exec_woman_emacs(const char *path, const char *page)
 257 {
 258         if (!check_emacsclient_version()) {
 259                 /* This works only with emacsclient version >= 22. */
 260                 struct strbuf man_page = STRBUF_INIT;
 261
 262                 if (!path)
 263                         path = "emacsclient";
 264                 strbuf_addf(&man_page, "(woman \"%s\")", page);
 265                 execlp(path, "emacsclient", "-e", man_page.buf, (char *)NULL);
 266                 warning_errno(_("failed to exec '%s'"), path);
 267                 strbuf_release(&man_page);
 268         }
 269 }
 270
 271 static void exec_man_konqueror(const char *path, const char *page)
 272 {
 273         const char *display = getenv("DISPLAY");
 274         if (display && *display) {
 275                 struct strbuf man_page = STRBUF_INIT;
 276                 const char *filename = "kfmclient";
 277
 278                 /* It's simpler to launch konqueror using kfmclient. */
 279                 if (path) {
 280                         size_t len;
 281                         if (strip_suffix(path, "/konqueror", &len))
 282                                 path = xstrfmt("%.*s/kfmclient", (int)len, path);
 283                         filename = basename((char *)path);
 284                 } else
 285                         path = "kfmclient";
 286                 strbuf_addf(&man_page, "man:%s(1)", page);
 287                 execlp(path, filename, "newTab", man_page.buf, (char *)NULL);
 288                 warning_errno(_("failed to exec '%s'"), path);
 289                 strbuf_release(&man_page);
 290         }
 291 }
 292
 293 static void exec_man_man(const char *path, const char *page)
 294 {
 295         if (!path)
 296                 path = "man";
 297         execlp(path, "man", page, (char *)NULL);
 298         warning_errno(_("failed to exec '%s'"), path);
 299 }
 300
 301 static void exec_man_cmd(const char *cmd, const char *page)
 302 {
 303         struct strbuf shell_cmd = STRBUF_INIT;
 304         strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 305         execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 306         warning(_("failed to exec '%s'"), cmd);
 307         strbuf_release(&shell_cmd);
 308 }
 309
 310 static void add_man_viewer(const char *name)
 311 {
 312         struct man_viewer_list **p = &man_viewer_list;
 313
 314         while (*p)
 315                 p = &((*p)->next);
 316         FLEX_ALLOC_STR(*p, name, name);
 317 }
 318
 319 static int supported_man_viewer(const char *name, size_t len)
 320 {
 321         return (!strncasecmp("man", name, len) ||
 322                 !strncasecmp("woman", name, len) ||
 323                 !strncasecmp("konqueror", name, len));
 324 }
 325
 326 static void do_add_man_viewer_info(const char *name,
 327                                    size_t len,
 328                                    const char *value)
 329 {
 330         struct man_viewer_info_list *new_man_viewer;
 331         FLEX_ALLOC_MEM(new_man_viewer, name, name, len);
 332         new_man_viewer->info = xstrdup(value);
 333         new_man_viewer->next = man_viewer_info_list;
 334         man_viewer_info_list = new_man_viewer;
 335 }
 336
 337 static int add_man_viewer_path(const char *name,
 338                                size_t len,
 339                                const char *value)
 340 {
 341         if (supported_man_viewer(name, len))
 342                 do_add_man_viewer_info(name, len, value);
 343         else
 344                 warning(_("'%s': path for unsupported man viewer.\n"
 345                           "Please consider using 'man.<tool>.cmd' instead."),
 346                         name);
 347
 348         return 0;
 349 }
 350
 351 static int add_man_viewer_cmd(const char *name,
 352                               size_t len,
 353                               const char *value)
 354 {
 355         if (supported_man_viewer(name, len))
 356                 warning(_("'%s': cmd for supported man viewer.\n"
 357                           "Please consider using 'man.<tool>.path' instead."),
 358                         name);
 359         else
 360                 do_add_man_viewer_info(name, len, value);
 361
 362         return 0;
 363 }
 364
 365 static int add_man_viewer_info(const char *var, const char *value)
 366 {
 367         const char *name, *subkey;
 368         size_t namelen;
 369
 370         if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
 371                 return 0;
 372
 373         if (!strcmp(subkey, "path")) {
 374                 if (!value)
 375                         return config_error_nonbool(var);
 376                 return add_man_viewer_path(name, namelen, value);
 377         }
 378         if (!strcmp(subkey, "cmd")) {
 379                 if (!value)
 380                         return config_error_nonbool(var);
 381                 return add_man_viewer_cmd(name, namelen, value);
 382         }
 383
 384         return 0;
 385 }
 386
 387 static int git_help_config(const char *var, const char *value, void *cb)
 388 {
 389         if (!strcmp(var, "help.format")) {
 390                 if (!value)
 391                         return config_error_nonbool(var);
 392                 help_format = parse_help_format(value);
 393                 return 0;
 394         }
 395         if (!strcmp(var, "help.htmlpath")) {
 396                 if (!value)
 397                         return config_error_nonbool(var);
 398                 html_path = xstrdup(value);
 399                 return 0;
 400         }
 401         if (!strcmp(var, "man.viewer")) {
 402                 if (!value)
 403                         return config_error_nonbool(var);
 404                 add_man_viewer(value);
 405                 return 0;
 406         }
 407         if (starts_with(var, "man."))
 408                 return add_man_viewer_info(var, value);
 409
 410         return git_default_config(var, value, cb);
 411 }
 412
 413 static struct cmdnames main_cmds, other_cmds;
 414
 415 static int is_git_command(const char *s)
 416 {
 417         if (is_builtin(s))
 418                 return 1;
 419
 420         load_command_list("git-", &main_cmds, &other_cmds);
 421         return is_in_cmdlist(&main_cmds, s) ||
 422                 is_in_cmdlist(&other_cmds, s);
 423 }
 424
 425 static const char *cmd_to_page(const char *git_cmd)
 426 {
 427         if (!git_cmd)
 428                 return "git";
 429         else if (starts_with(git_cmd, "git"))
 430                 return git_cmd;
 431         else if (is_git_command(git_cmd))
 432                 return xstrfmt("git-%s", git_cmd);
 433         else
 434                 return xstrfmt("git%s", git_cmd);
 435 }
 436
 437 static void setup_man_path(void)
 438 {
 439         struct strbuf new_path = STRBUF_INIT;
 440         const char *old_path = getenv("MANPATH");
 441         char *git_man_path = system_path(GIT_MAN_PATH);
 442
 443         /* We should always put ':' after our path. If there is no
 444          * old_path, the ':' at the end will let 'man' to try
 445          * system-wide paths after ours to find the manual page. If
 446          * there is old_path, we need ':' as delimiter. */
 447         strbuf_addstr(&new_path, git_man_path);
 448         strbuf_addch(&new_path, ':');
 449         if (old_path)
 450                 strbuf_addstr(&new_path, old_path);
 451
 452         free(git_man_path);
 453         setenv("MANPATH", new_path.buf, 1);
 454
 455         strbuf_release(&new_path);
 456 }
 457
 458 static void exec_viewer(const char *name, const char *page)
 459 {
 460         const char *info = get_man_viewer_info(name);
 461
 462         if (!strcasecmp(name, "man"))
 463                 exec_man_man(info, page);
 464         else if (!strcasecmp(name, "woman"))
 465                 exec_woman_emacs(info, page);
 466         else if (!strcasecmp(name, "konqueror"))
 467                 exec_man_konqueror(info, page);
 468         else if (info)
 469                 exec_man_cmd(info, page);
 470         else
 471                 warning(_("'%s': unknown man viewer."), name);
 472 }
 473
 474 static void show_man_page(const char *page)
 475 {
 476         struct man_viewer_list *viewer;
 477         const char *fallback = getenv("GIT_MAN_VIEWER");
 478
 479         setup_man_path();
 480         for (viewer = man_viewer_list; viewer; viewer = viewer->next)
 481         {
 482                 exec_viewer(viewer->name, page); /* will return when unable */
 483         }
 484         if (fallback)
 485                 exec_viewer(fallback, page);
 486         exec_viewer("man", page);
 487         die(_("no man viewer handled the request"));
 488 }
 489
 490 static void show_info_page(const char *page)
 491 {
 492         setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
 493         execlp("info", "info", "gitman", page, (char *)NULL);
 494         die(_("no info viewer handled the request"));
 495 }
 496
 497 static void get_html_page_path(struct strbuf *page_path, const char *page)
 498 {
 499         struct stat st;
 500         char *to_free = NULL;
 501
 502         if (!html_path)
 503                 html_path = to_free = system_path(GIT_HTML_PATH);
 504
 505         /*
 506          * Check that the page we're looking for exists.
 507          */
 508         if (!strstr(html_path, "://")) {
 509                 if (stat(mkpath("%s/%s.html", html_path, page), &st)
 510                     || !S_ISREG(st.st_mode))
 511                         die("'%s/%s.html': documentation file not found.",
 512                                 html_path, page);
 513         }
 514
 515         strbuf_init(page_path, 0);
 516         strbuf_addf(page_path, "%s/%s.html", html_path, page);
 517         free(to_free);
 518 }
 519
 520 static void open_html(const char *path)
 521 {
 522         execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
 523 }
 524
 525 static void show_html_page(const char *page)
 526 {
 527         struct strbuf page_path; /* it leaks but we exec bellow */
 528
 529         get_html_page_path(&page_path, page);
 530
 531         open_html(page_path.buf);
 532 }
 533
 534 static const char *check_git_cmd(const char* cmd)
 535 {
 536         char *alias;
 537
 538         if (is_git_command(cmd))
 539                 return cmd;
 540
 541         alias = alias_lookup(cmd);
 542         if (alias) {
 543                 const char **argv;
 544                 int count;
 545
 546                 /*
 547                  * handle_builtin() in git.c rewrites "git cmd --help"
 548                  * to "git help --exclude-guides cmd", so we can use
 549                  * exclude_guides to distinguish "git cmd --help" from
 550                  * "git help cmd". In the latter case, or if cmd is an
 551                  * alias for a shell command, just print the alias
 552                  * definition.
 553                  */
 554                 if (!exclude_guides || alias[0] == '!') {
 555                         printf_ln(_("'%s' is aliased to '%s'"), cmd, alias);
 556                         free(alias);
 557                         exit(0);
 558                 }
 559                 /*
 560                  * Otherwise, we pretend that the command was "git
 561                  * word0 --help". We use split_cmdline() to get the
 562                  * first word of the alias, to ensure that we use the
 563                  * same rules as when the alias is actually
 564                  * used. split_cmdline() modifies alias in-place.
 565                  */
 566                 fprintf_ln(stderr, _("'%s' is aliased to '%s'"), cmd, alias);
 567                 count = split_cmdline(alias, &argv);
 568                 if (count < 0)
 569                         die(_("bad alias.%s string: %s"), cmd,
 570                             split_cmdline_strerror(count));
 571                 free(argv);
 572                 UNLEAK(alias);
 573                 return alias;
 574         }
 575
 576         if (exclude_guides)
 577                 return help_unknown_cmd(cmd);
 578
 579         return cmd;
 580 }
 581
 582 static void no_help_format(const char *opt_mode, enum help_format fmt)
 583 {
 584         const char *opt_fmt;
 585
 586         switch (fmt) {
 587         case HELP_FORMAT_NONE:
 588                 return;
 589         case HELP_FORMAT_MAN:
 590                 opt_fmt = "--man";
 591                 break;
 592         case HELP_FORMAT_INFO:
 593                 opt_fmt = "--info";
 594                 break;
 595         case HELP_FORMAT_WEB:
 596                 opt_fmt = "--web";
 597                 break;
 598         default:
 599                 BUG("unreachable");
 600         }
 601
 602         usage_msg_optf(_("options '%s' and '%s' cannot be used together"),
 603                        builtin_help_usage, builtin_help_options, opt_mode,
 604                        opt_fmt);
 605 }
 606
 607 static void opt_mode_usage(int argc, const char *opt_mode,
 608                            enum help_format fmt)
 609 {
 610         if (argc)
 611                 usage_msg_optf(_("the '%s' option doesn't take any non-option arguments"),
 612                                builtin_help_usage, builtin_help_options,
 613                                opt_mode);
 614
 615         no_help_format(opt_mode, fmt);
 616 }
 617
 618 int cmd_help(int argc, const char **argv, const char *prefix)
 619 {
 620         int nongit;
 621         enum help_format parsed_help_format;
 622         const char *page;
 623
 624         argc = parse_options(argc, argv, prefix, builtin_help_options,
 625                         builtin_help_usage, 0);
 626         parsed_help_format = help_format;
 627
 628         if (cmd_mode != HELP_ACTION_ALL &&
 629             (show_external_commands >= 0 ||
 630              show_aliases >= 0))
 631                 usage_msg_opt(_("the '--no-[external-commands|aliases]' options can only be used with '--all'"),
 632                               builtin_help_usage, builtin_help_options);
 633
 634         switch (cmd_mode) {
 635         case HELP_ACTION_ALL:
 636                 opt_mode_usage(argc, "--all", help_format);
 637                 if (verbose) {
 638                         setup_pager();
 639                         list_all_cmds_help(show_external_commands,
 640                                            show_aliases);
 641                         return 0;
 642                 }
 643                 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 644                 load_command_list("git-", &main_cmds, &other_cmds);
 645                 list_commands(&main_cmds, &other_cmds);
 646                 printf("%s\n", _(git_more_info_string));
 647                 break;
 648         case HELP_ACTION_GUIDES:
 649                 opt_mode_usage(argc, "--guides", help_format);
 650                 list_guides_help();
 651                 printf("%s\n", _(git_more_info_string));
 652                 return 0;
 653         case HELP_ACTION_CONFIG_FOR_COMPLETION:
 654                 opt_mode_usage(argc, "--config-for-completion", help_format);
 655                 list_config_help(SHOW_CONFIG_VARS);
 656                 return 0;
 657         case HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION:
 658                 opt_mode_usage(argc, "--config-sections-for-completion",
 659                                help_format);
 660                 list_config_help(SHOW_CONFIG_SECTIONS);
 661                 return 0;
 662         case HELP_ACTION_CONFIG:
 663                 opt_mode_usage(argc, "--config", help_format);
 664                 setup_pager();
 665                 list_config_help(SHOW_CONFIG_HUMAN);
 666                 printf("\n%s\n", _("'git help config' for more information"));
 667                 return 0;
 668         }
 669
 670         if (!argv[0]) {
 671                 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 672                 list_common_cmds_help();
 673                 printf("\n%s\n", _(git_more_info_string));
 674                 return 0;
 675         }
 676
 677         setup_git_directory_gently(&nongit);
 678         git_config(git_help_config, NULL);
 679
 680         if (parsed_help_format != HELP_FORMAT_NONE)
 681                 help_format = parsed_help_format;
 682         if (help_format == HELP_FORMAT_NONE)
 683                 help_format = parse_help_format(DEFAULT_HELP_FORMAT);
 684
 685         argv[0] = check_git_cmd(argv[0]);
 686
 687         page = cmd_to_page(argv[0]);
 688         switch (help_format) {
 689         case HELP_FORMAT_NONE:
 690         case HELP_FORMAT_MAN:
 691                 show_man_page(page);
 692                 break;
 693         case HELP_FORMAT_INFO:
 694                 show_info_page(page);
 695                 break;
 696         case HELP_FORMAT_WEB:
 697                 show_html_page(page);
 698                 break;
 699         }
 700
 701         return 0;
 702 }