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 "gettext.h"
   9 #include "pager.h"
  10 #include "parse-options.h"
  11 #include "run-command.h"
  12 #include "config-list.h"
  13 #include "help.h"
  14 #include "alias.h"
  15 #include "setup.h"
  16
  17 #ifndef DEFAULT_HELP_FORMAT
  18 #define DEFAULT_HELP_FORMAT "man"
  19 #endif
  20
  21 static struct man_viewer_list {
  22         struct man_viewer_list *next;
  23         char name[FLEX_ARRAY];
  24 } *man_viewer_list;
  25
  26 static struct man_viewer_info_list {
  27         struct man_viewer_info_list *next;
  28         const char *info;
  29         char name[FLEX_ARRAY];
  30 } *man_viewer_info_list;
  31
  32 enum help_format {
  33         HELP_FORMAT_NONE,
  34         HELP_FORMAT_MAN,
  35         HELP_FORMAT_INFO,
  36         HELP_FORMAT_WEB
  37 };
  38
  39 enum show_config_type {
  40         SHOW_CONFIG_HUMAN,
  41         SHOW_CONFIG_VARS,
  42         SHOW_CONFIG_SECTIONS,
  43 };
  44
  45 static enum help_action {
  46         HELP_ACTION_ALL = 1,
  47         HELP_ACTION_GUIDES,
  48         HELP_ACTION_CONFIG,
  49         HELP_ACTION_USER_INTERFACES,
  50         HELP_ACTION_DEVELOPER_INTERFACES,
  51         HELP_ACTION_CONFIG_FOR_COMPLETION,
  52         HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION,
  53 } cmd_mode;
  54
  55 static const char *html_path;
  56 static int verbose = 1;
  57 static enum help_format help_format = HELP_FORMAT_NONE;
  58 static int exclude_guides;
  59 static int show_external_commands = -1;
  60 static int show_aliases = -1;
  61 static struct option builtin_help_options[] = {
  62         OPT_CMDMODE('a', "all", &cmd_mode, N_("print all available commands"),
  63                     HELP_ACTION_ALL),
  64         OPT_BOOL(0, "external-commands", &show_external_commands,
  65                  N_("show external commands in --all")),
  66         OPT_BOOL(0, "aliases", &show_aliases, N_("show aliases in --all")),
  67         OPT_HIDDEN_BOOL(0, "exclude-guides", &exclude_guides, N_("exclude guides")),
  68         OPT_SET_INT('m', "man", &help_format, N_("show man page"), HELP_FORMAT_MAN),
  69         OPT_SET_INT('w', "web", &help_format, N_("show manual in web browser"),
  70                         HELP_FORMAT_WEB),
  71         OPT_SET_INT('i', "info", &help_format, N_("show info page"),
  72                         HELP_FORMAT_INFO),
  73         OPT__VERBOSE(&verbose, N_("print command description")),
  74
  75         OPT_CMDMODE('g', "guides", &cmd_mode, N_("print list of useful guides"),
  76                     HELP_ACTION_GUIDES),
  77         OPT_CMDMODE(0, "user-interfaces", &cmd_mode,
  78                     N_("print list of user-facing repository, command and file interfaces"),
  79                     HELP_ACTION_USER_INTERFACES),
  80         OPT_CMDMODE(0, "developer-interfaces", &cmd_mode,
  81                     N_("print list of file formats, protocols and other developer interfaces"),
  82                     HELP_ACTION_DEVELOPER_INTERFACES),
  83         OPT_CMDMODE('c', "config", &cmd_mode, N_("print all configuration variable names"),
  84                     HELP_ACTION_CONFIG),
  85         OPT_CMDMODE_F(0, "config-for-completion", &cmd_mode, "",
  86                     HELP_ACTION_CONFIG_FOR_COMPLETION, PARSE_OPT_HIDDEN),
  87         OPT_CMDMODE_F(0, "config-sections-for-completion", &cmd_mode, "",
  88                     HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION, PARSE_OPT_HIDDEN),
  89
  90         OPT_END(),
  91 };
  92
  93 static const char * const builtin_help_usage[] = {
  94         "git help [-a|--all] [--[no-]verbose] [--[no-]external-commands] [--[no-]aliases]",
  95         N_("git help [[-i|--info] [-m|--man] [-w|--web]] [<command>|<doc>]"),
  96         "git help [-g|--guides]",
  97         "git help [-c|--config]",
  98         "git help [--user-interfaces]",
  99         "git help [--developer-interfaces]",
 100         NULL
 101 };
 102
 103 struct slot_expansion {
 104         const char *prefix;
 105         const char *placeholder;
 106         void (*fn)(struct string_list *list, const char *prefix);
 107         int found;
 108 };
 109
 110 static void list_config_help(enum show_config_type type)
 111 {
 112         struct slot_expansion slot_expansions[] = {
 113                 { "advice", "*", list_config_advices },
 114                 { "color.branch", "<slot>", list_config_color_branch_slots },
 115                 { "color.decorate", "<slot>", list_config_color_decorate_slots },
 116                 { "color.diff", "<slot>", list_config_color_diff_slots },
 117                 { "color.grep", "<slot>", list_config_color_grep_slots },
 118                 { "color.interactive", "<slot>", list_config_color_interactive_slots },
 119                 { "color.remote", "<slot>", list_config_color_sideband_slots },
 120                 { "color.status", "<slot>", list_config_color_status_slots },
 121                 { "fsck", "<msg-id>", list_config_fsck_msg_ids },
 122                 { "receive.fsck", "<msg-id>", list_config_fsck_msg_ids },
 123                 { NULL, NULL, NULL }
 124         };
 125         const char **p;
 126         struct slot_expansion *e;
 127         struct string_list keys = STRING_LIST_INIT_DUP;
 128         struct string_list keys_uniq = STRING_LIST_INIT_DUP;
 129         struct string_list_item *item;
 130         int i;
 131
 132         for (p = config_name_list; *p; p++) {
 133                 const char *var = *p;
 134                 struct strbuf sb = STRBUF_INIT;
 135
 136                 for (e = slot_expansions; e->prefix; e++) {
 137
 138                         strbuf_reset(&sb);
 139                         strbuf_addf(&sb, "%s.%s", e->prefix, e->placeholder);
 140                         if (!strcasecmp(var, sb.buf)) {
 141                                 e->fn(&keys, e->prefix);
 142                                 e->found++;
 143                                 break;
 144                         }
 145                 }
 146                 strbuf_release(&sb);
 147                 if (!e->prefix)
 148                         string_list_append(&keys, var);
 149         }
 150
 151         for (e = slot_expansions; e->prefix; e++)
 152                 if (!e->found)
 153                         BUG("slot_expansion %s.%s is not used",
 154                             e->prefix, e->placeholder);
 155
 156         string_list_sort(&keys);
 157         for (i = 0; i < keys.nr; i++) {
 158                 const char *var = keys.items[i].string;
 159                 const char *wildcard, *tag, *cut;
 160                 const char *dot = NULL;
 161                 struct strbuf sb = STRBUF_INIT;
 162
 163                 switch (type) {
 164                 case SHOW_CONFIG_HUMAN:
 165                         puts(var);
 166                         continue;
 167                 case SHOW_CONFIG_SECTIONS:
 168                         dot = strchr(var, '.');
 169                         break;
 170                 case SHOW_CONFIG_VARS:
 171                         break;
 172                 }
 173                 wildcard = strchr(var, '*');
 174                 tag = strchr(var, '<');
 175
 176                 if (!dot && !wildcard && !tag) {
 177                         string_list_append(&keys_uniq, var);
 178                         continue;
 179                 }
 180
 181                 if (dot)
 182                         cut = dot;
 183                 else if (wildcard && !tag)
 184                         cut = wildcard;
 185                 else if (!wildcard && tag)
 186                         cut = tag;
 187                 else
 188                         cut = wildcard < tag ? wildcard : tag;
 189
 190                 strbuf_add(&sb, var, cut - var);
 191                 string_list_append(&keys_uniq, sb.buf);
 192                 strbuf_release(&sb);
 193
 194         }
 195         string_list_clear(&keys, 0);
 196         string_list_remove_duplicates(&keys_uniq, 0);
 197         for_each_string_list_item(item, &keys_uniq)
 198                 puts(item->string);
 199         string_list_clear(&keys_uniq, 0);
 200 }
 201
 202 static enum help_format parse_help_format(const char *format)
 203 {
 204         if (!strcmp(format, "man"))
 205                 return HELP_FORMAT_MAN;
 206         if (!strcmp(format, "info"))
 207                 return HELP_FORMAT_INFO;
 208         if (!strcmp(format, "web") || !strcmp(format, "html"))
 209                 return HELP_FORMAT_WEB;
 210         /*
 211          * Please update _git_config() in git-completion.bash when you
 212          * add new help formats.
 213          */
 214         die(_("unrecognized help format '%s'"), format);
 215 }
 216
 217 static const char *get_man_viewer_info(const char *name)
 218 {
 219         struct man_viewer_info_list *viewer;
 220
 221         for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
 222         {
 223                 if (!strcasecmp(name, viewer->name))
 224                         return viewer->info;
 225         }
 226         return NULL;
 227 }
 228
 229 static int check_emacsclient_version(void)
 230 {
 231         struct strbuf buffer = STRBUF_INIT;
 232         struct child_process ec_process = CHILD_PROCESS_INIT;
 233         int version;
 234
 235         /* emacsclient prints its version number on stderr */
 236         strvec_pushl(&ec_process.args, "emacsclient", "--version", NULL);
 237         ec_process.err = -1;
 238         ec_process.stdout_to_stderr = 1;
 239         if (start_command(&ec_process))
 240                 return error(_("Failed to start emacsclient."));
 241
 242         strbuf_read(&buffer, ec_process.err, 20);
 243         close(ec_process.err);
 244
 245         /*
 246          * Don't bother checking return value, because "emacsclient --version"
 247          * seems to always exits with code 1.
 248          */
 249         finish_command(&ec_process);
 250
 251         if (!starts_with(buffer.buf, "emacsclient")) {
 252                 strbuf_release(&buffer);
 253                 return error(_("Failed to parse emacsclient version."));
 254         }
 255
 256         strbuf_remove(&buffer, 0, strlen("emacsclient"));
 257         version = atoi(buffer.buf);
 258
 259         if (version < 22) {
 260                 strbuf_release(&buffer);
 261                 return error(_("emacsclient version '%d' too old (< 22)."),
 262                         version);
 263         }
 264
 265         strbuf_release(&buffer);
 266         return 0;
 267 }
 268
 269 static void exec_woman_emacs(const char *path, const char *page)
 270 {
 271         if (!check_emacsclient_version()) {
 272                 /* This works only with emacsclient version >= 22. */
 273                 struct strbuf man_page = STRBUF_INIT;
 274
 275                 if (!path)
 276                         path = "emacsclient";
 277                 strbuf_addf(&man_page, "(woman \"%s\")", page);
 278                 execlp(path, "emacsclient", "-e", man_page.buf, (char *)NULL);
 279                 warning_errno(_("failed to exec '%s'"), path);
 280                 strbuf_release(&man_page);
 281         }
 282 }
 283
 284 static void exec_man_konqueror(const char *path, const char *page)
 285 {
 286         const char *display = getenv("DISPLAY");
 287         if (display && *display) {
 288                 struct strbuf man_page = STRBUF_INIT;
 289                 const char *filename = "kfmclient";
 290
 291                 /* It's simpler to launch konqueror using kfmclient. */
 292                 if (path) {
 293                         size_t len;
 294                         if (strip_suffix(path, "/konqueror", &len))
 295                                 path = xstrfmt("%.*s/kfmclient", (int)len, path);
 296                         filename = basename((char *)path);
 297                 } else
 298                         path = "kfmclient";
 299                 strbuf_addf(&man_page, "man:%s(1)", page);
 300                 execlp(path, filename, "newTab", man_page.buf, (char *)NULL);
 301                 warning_errno(_("failed to exec '%s'"), path);
 302                 strbuf_release(&man_page);
 303         }
 304 }
 305
 306 static void exec_man_man(const char *path, const char *page)
 307 {
 308         if (!path)
 309                 path = "man";
 310         execlp(path, "man", page, (char *)NULL);
 311         warning_errno(_("failed to exec '%s'"), path);
 312 }
 313
 314 static void exec_man_cmd(const char *cmd, const char *page)
 315 {
 316         struct strbuf shell_cmd = STRBUF_INIT;
 317         strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 318         execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 319         warning(_("failed to exec '%s'"), cmd);
 320         strbuf_release(&shell_cmd);
 321 }
 322
 323 static void add_man_viewer(const char *name)
 324 {
 325         struct man_viewer_list **p = &man_viewer_list;
 326
 327         while (*p)
 328                 p = &((*p)->next);
 329         FLEX_ALLOC_STR(*p, name, name);
 330 }
 331
 332 static int supported_man_viewer(const char *name, size_t len)
 333 {
 334         return (!strncasecmp("man", name, len) ||
 335                 !strncasecmp("woman", name, len) ||
 336                 !strncasecmp("konqueror", name, len));
 337 }
 338
 339 static void do_add_man_viewer_info(const char *name,
 340                                    size_t len,
 341                                    const char *value)
 342 {
 343         struct man_viewer_info_list *new_man_viewer;
 344         FLEX_ALLOC_MEM(new_man_viewer, name, name, len);
 345         new_man_viewer->info = xstrdup(value);
 346         new_man_viewer->next = man_viewer_info_list;
 347         man_viewer_info_list = new_man_viewer;
 348 }
 349
 350 static int add_man_viewer_path(const char *name,
 351                                size_t len,
 352                                const char *value)
 353 {
 354         if (supported_man_viewer(name, len))
 355                 do_add_man_viewer_info(name, len, value);
 356         else
 357                 warning(_("'%s': path for unsupported man viewer.\n"
 358                           "Please consider using 'man.<tool>.cmd' instead."),
 359                         name);
 360
 361         return 0;
 362 }
 363
 364 static int add_man_viewer_cmd(const char *name,
 365                               size_t len,
 366                               const char *value)
 367 {
 368         if (supported_man_viewer(name, len))
 369                 warning(_("'%s': cmd for supported man viewer.\n"
 370                           "Please consider using 'man.<tool>.path' instead."),
 371                         name);
 372         else
 373                 do_add_man_viewer_info(name, len, value);
 374
 375         return 0;
 376 }
 377
 378 static int add_man_viewer_info(const char *var, const char *value)
 379 {
 380         const char *name, *subkey;
 381         size_t namelen;
 382
 383         if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
 384                 return 0;
 385
 386         if (!strcmp(subkey, "path")) {
 387                 if (!value)
 388                         return config_error_nonbool(var);
 389                 return add_man_viewer_path(name, namelen, value);
 390         }
 391         if (!strcmp(subkey, "cmd")) {
 392                 if (!value)
 393                         return config_error_nonbool(var);
 394                 return add_man_viewer_cmd(name, namelen, value);
 395         }
 396
 397         return 0;
 398 }
 399
 400 static int git_help_config(const char *var, const char *value, void *cb)
 401 {
 402         if (!strcmp(var, "help.format")) {
 403                 if (!value)
 404                         return config_error_nonbool(var);
 405                 help_format = parse_help_format(value);
 406                 return 0;
 407         }
 408         if (!strcmp(var, "help.htmlpath")) {
 409                 if (!value)
 410                         return config_error_nonbool(var);
 411                 html_path = xstrdup(value);
 412                 return 0;
 413         }
 414         if (!strcmp(var, "man.viewer")) {
 415                 if (!value)
 416                         return config_error_nonbool(var);
 417                 add_man_viewer(value);
 418                 return 0;
 419         }
 420         if (starts_with(var, "man."))
 421                 return add_man_viewer_info(var, value);
 422
 423         return git_default_config(var, value, cb);
 424 }
 425
 426 static struct cmdnames main_cmds, other_cmds;
 427
 428 static int is_git_command(const char *s)
 429 {
 430         if (is_builtin(s))
 431                 return 1;
 432
 433         load_command_list("git-", &main_cmds, &other_cmds);
 434         return is_in_cmdlist(&main_cmds, s) ||
 435                 is_in_cmdlist(&other_cmds, s);
 436 }
 437
 438 static const char *cmd_to_page(const char *git_cmd)
 439 {
 440         if (!git_cmd)
 441                 return "git";
 442         else if (starts_with(git_cmd, "git"))
 443                 return git_cmd;
 444         else if (is_git_command(git_cmd))
 445                 return xstrfmt("git-%s", git_cmd);
 446         else if (!strcmp("scalar", git_cmd))
 447                 return xstrdup(git_cmd);
 448         else
 449                 return xstrfmt("git%s", git_cmd);
 450 }
 451
 452 static void setup_man_path(void)
 453 {
 454         struct strbuf new_path = STRBUF_INIT;
 455         const char *old_path = getenv("MANPATH");
 456         char *git_man_path = system_path(GIT_MAN_PATH);
 457
 458         /* We should always put ':' after our path. If there is no
 459          * old_path, the ':' at the end will let 'man' to try
 460          * system-wide paths after ours to find the manual page. If
 461          * there is old_path, we need ':' as delimiter. */
 462         strbuf_addstr(&new_path, git_man_path);
 463         strbuf_addch(&new_path, ':');
 464         if (old_path)
 465                 strbuf_addstr(&new_path, old_path);
 466
 467         free(git_man_path);
 468         setenv("MANPATH", new_path.buf, 1);
 469
 470         strbuf_release(&new_path);
 471 }
 472
 473 static void exec_viewer(const char *name, const char *page)
 474 {
 475         const char *info = get_man_viewer_info(name);
 476
 477         if (!strcasecmp(name, "man"))
 478                 exec_man_man(info, page);
 479         else if (!strcasecmp(name, "woman"))
 480                 exec_woman_emacs(info, page);
 481         else if (!strcasecmp(name, "konqueror"))
 482                 exec_man_konqueror(info, page);
 483         else if (info)
 484                 exec_man_cmd(info, page);
 485         else
 486                 warning(_("'%s': unknown man viewer."), name);
 487 }
 488
 489 static void show_man_page(const char *page)
 490 {
 491         struct man_viewer_list *viewer;
 492         const char *fallback = getenv("GIT_MAN_VIEWER");
 493
 494         setup_man_path();
 495         for (viewer = man_viewer_list; viewer; viewer = viewer->next)
 496         {
 497                 exec_viewer(viewer->name, page); /* will return when unable */
 498         }
 499         if (fallback)
 500                 exec_viewer(fallback, page);
 501         exec_viewer("man", page);
 502         die(_("no man viewer handled the request"));
 503 }
 504
 505 static void show_info_page(const char *page)
 506 {
 507         setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
 508         execlp("info", "info", "gitman", page, (char *)NULL);
 509         die(_("no info viewer handled the request"));
 510 }
 511
 512 static void get_html_page_path(struct strbuf *page_path, const char *page)
 513 {
 514         struct stat st;
 515         char *to_free = NULL;
 516
 517         if (!html_path)
 518                 html_path = to_free = system_path(GIT_HTML_PATH);
 519
 520         /*
 521          * Check that the page we're looking for exists.
 522          */
 523         if (!strstr(html_path, "://")) {
 524                 if (stat(mkpath("%s/%s.html", html_path, page), &st)
 525                     || !S_ISREG(st.st_mode))
 526                         die("'%s/%s.html': documentation file not found.",
 527                                 html_path, page);
 528         }
 529
 530         strbuf_init(page_path, 0);
 531         strbuf_addf(page_path, "%s/%s.html", html_path, page);
 532         free(to_free);
 533 }
 534
 535 static void open_html(const char *path)
 536 {
 537         execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
 538 }
 539
 540 static void show_html_page(const char *page)
 541 {
 542         struct strbuf page_path; /* it leaks but we exec bellow */
 543
 544         get_html_page_path(&page_path, page);
 545
 546         open_html(page_path.buf);
 547 }
 548
 549 static const char *check_git_cmd(const char* cmd)
 550 {
 551         char *alias;
 552
 553         if (is_git_command(cmd))
 554                 return cmd;
 555
 556         alias = alias_lookup(cmd);
 557         if (alias) {
 558                 const char **argv;
 559                 int count;
 560
 561                 /*
 562                  * handle_builtin() in git.c rewrites "git cmd --help"
 563                  * to "git help --exclude-guides cmd", so we can use
 564                  * exclude_guides to distinguish "git cmd --help" from
 565                  * "git help cmd". In the latter case, or if cmd is an
 566                  * alias for a shell command, just print the alias
 567                  * definition.
 568                  */
 569                 if (!exclude_guides || alias[0] == '!') {
 570                         printf_ln(_("'%s' is aliased to '%s'"), cmd, alias);
 571                         free(alias);
 572                         exit(0);
 573                 }
 574                 /*
 575                  * Otherwise, we pretend that the command was "git
 576                  * word0 --help". We use split_cmdline() to get the
 577                  * first word of the alias, to ensure that we use the
 578                  * same rules as when the alias is actually
 579                  * used. split_cmdline() modifies alias in-place.
 580                  */
 581                 fprintf_ln(stderr, _("'%s' is aliased to '%s'"), cmd, alias);
 582                 count = split_cmdline(alias, &argv);
 583                 if (count < 0)
 584                         die(_("bad alias.%s string: %s"), cmd,
 585                             split_cmdline_strerror(count));
 586                 free(argv);
 587                 UNLEAK(alias);
 588                 return alias;
 589         }
 590
 591         if (exclude_guides)
 592                 return help_unknown_cmd(cmd);
 593
 594         return cmd;
 595 }
 596
 597 static void no_help_format(const char *opt_mode, enum help_format fmt)
 598 {
 599         const char *opt_fmt;
 600
 601         switch (fmt) {
 602         case HELP_FORMAT_NONE:
 603                 return;
 604         case HELP_FORMAT_MAN:
 605                 opt_fmt = "--man";
 606                 break;
 607         case HELP_FORMAT_INFO:
 608                 opt_fmt = "--info";
 609                 break;
 610         case HELP_FORMAT_WEB:
 611                 opt_fmt = "--web";
 612                 break;
 613         default:
 614                 BUG("unreachable");
 615         }
 616
 617         usage_msg_optf(_("options '%s' and '%s' cannot be used together"),
 618                        builtin_help_usage, builtin_help_options, opt_mode,
 619                        opt_fmt);
 620 }
 621
 622 static void opt_mode_usage(int argc, const char *opt_mode,
 623                            enum help_format fmt)
 624 {
 625         if (argc)
 626                 usage_msg_optf(_("the '%s' option doesn't take any non-option arguments"),
 627                                builtin_help_usage, builtin_help_options,
 628                                opt_mode);
 629
 630         no_help_format(opt_mode, fmt);
 631 }
 632
 633 int cmd_help(int argc, const char **argv, const char *prefix)
 634 {
 635         int nongit;
 636         enum help_format parsed_help_format;
 637         const char *page;
 638
 639         argc = parse_options(argc, argv, prefix, builtin_help_options,
 640                         builtin_help_usage, 0);
 641         parsed_help_format = help_format;
 642
 643         if (cmd_mode != HELP_ACTION_ALL &&
 644             (show_external_commands >= 0 ||
 645              show_aliases >= 0))
 646                 usage_msg_opt(_("the '--no-[external-commands|aliases]' options can only be used with '--all'"),
 647                               builtin_help_usage, builtin_help_options);
 648
 649         switch (cmd_mode) {
 650         case HELP_ACTION_ALL:
 651                 opt_mode_usage(argc, "--all", help_format);
 652                 if (verbose) {
 653                         setup_pager();
 654                         list_all_cmds_help(show_external_commands,
 655                                            show_aliases);
 656                         return 0;
 657                 }
 658                 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 659                 load_command_list("git-", &main_cmds, &other_cmds);
 660                 list_commands(&main_cmds, &other_cmds);
 661                 printf("%s\n", _(git_more_info_string));
 662                 break;
 663         case HELP_ACTION_GUIDES:
 664                 opt_mode_usage(argc, "--guides", help_format);
 665                 list_guides_help();
 666                 printf("%s\n", _(git_more_info_string));
 667                 return 0;
 668         case HELP_ACTION_CONFIG_FOR_COMPLETION:
 669                 opt_mode_usage(argc, "--config-for-completion", help_format);
 670                 list_config_help(SHOW_CONFIG_VARS);
 671                 return 0;
 672         case HELP_ACTION_USER_INTERFACES:
 673                 opt_mode_usage(argc, "--user-interfaces", help_format);
 674                 list_user_interfaces_help();
 675                 return 0;
 676         case HELP_ACTION_DEVELOPER_INTERFACES:
 677                 opt_mode_usage(argc, "--developer-interfaces", help_format);
 678                 list_developer_interfaces_help();
 679                 return 0;
 680         case HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION:
 681                 opt_mode_usage(argc, "--config-sections-for-completion",
 682                                help_format);
 683                 list_config_help(SHOW_CONFIG_SECTIONS);
 684                 return 0;
 685         case HELP_ACTION_CONFIG:
 686                 opt_mode_usage(argc, "--config", help_format);
 687                 setup_pager();
 688                 list_config_help(SHOW_CONFIG_HUMAN);
 689                 printf("\n%s\n", _("'git help config' for more information"));
 690                 return 0;
 691         }
 692
 693         if (!argv[0]) {
 694                 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 695                 list_common_cmds_help();
 696                 printf("\n%s\n", _(git_more_info_string));
 697                 return 0;
 698         }
 699
 700         setup_git_directory_gently(&nongit);
 701         git_config(git_help_config, NULL);
 702
 703         if (parsed_help_format != HELP_FORMAT_NONE)
 704                 help_format = parsed_help_format;
 705         if (help_format == HELP_FORMAT_NONE)
 706                 help_format = parse_help_format(DEFAULT_HELP_FORMAT);
 707
 708         argv[0] = check_git_cmd(argv[0]);
 709
 710         page = cmd_to_page(argv[0]);
 711         switch (help_format) {
 712         case HELP_FORMAT_NONE:
 713         case HELP_FORMAT_MAN:
 714                 show_man_page(page);
 715                 break;
 716         case HELP_FORMAT_INFO:
 717                 show_info_page(page);
 718                 break;
 719         case HELP_FORMAT_WEB:
 720                 show_html_page(page);
 721                 break;
 722         }
 723
 724         return 0;
 725 }