t1502, docs: disallow --no-help
[git/debian.git] / builtin / help.c
blobdc1fbe2b9862df507dc1e077258d3c44048eebef
1 /*
2 * Builtin help command
3 */
4 #include "builtin.h"
5 #include "config.h"
6 #include "exec-cmd.h"
7 #include "gettext.h"
8 #include "pager.h"
9 #include "parse-options.h"
10 #include "path.h"
11 #include "run-command.h"
12 #include "config-list.h"
13 #include "help.h"
14 #include "alias.h"
15 #include "setup.h"
17 #ifndef DEFAULT_HELP_FORMAT
18 #define DEFAULT_HELP_FORMAT "man"
19 #endif
21 static struct man_viewer_list {
22 struct man_viewer_list *next;
23 char name[FLEX_ARRAY];
24 } *man_viewer_list;
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;
32 enum help_format {
33 HELP_FORMAT_NONE,
34 HELP_FORMAT_MAN,
35 HELP_FORMAT_INFO,
36 HELP_FORMAT_WEB
39 enum show_config_type {
40 SHOW_CONFIG_HUMAN,
41 SHOW_CONFIG_VARS,
42 SHOW_CONFIG_SECTIONS,
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;
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")),
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),
90 OPT_END(),
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
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;
110 static void list_config_help(enum show_config_type type)
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 }
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;
132 for (p = config_name_list; *p; p++) {
133 const char *var = *p;
134 struct strbuf sb = STRBUF_INIT;
136 for (e = slot_expansions; e->prefix; e++) {
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;
146 strbuf_release(&sb);
147 if (!e->prefix)
148 string_list_append(&keys, var);
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);
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;
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;
173 wildcard = strchr(var, '*');
174 tag = strchr(var, '<');
176 if (!dot && !wildcard && !tag) {
177 string_list_append(&keys_uniq, var);
178 continue;
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;
190 strbuf_add(&sb, var, cut - var);
191 string_list_append(&keys_uniq, sb.buf);
192 strbuf_release(&sb);
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);
202 static enum help_format parse_help_format(const char *format)
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;
211 * Please update _git_config() in git-completion.bash when you
212 * add new help formats.
214 die(_("unrecognized help format '%s'"), format);
217 static const char *get_man_viewer_info(const char *name)
219 struct man_viewer_info_list *viewer;
221 for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
223 if (!strcasecmp(name, viewer->name))
224 return viewer->info;
226 return NULL;
229 static int check_emacsclient_version(void)
231 struct strbuf buffer = STRBUF_INIT;
232 struct child_process ec_process = CHILD_PROCESS_INIT;
233 int version;
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."));
242 strbuf_read(&buffer, ec_process.err, 20);
243 close(ec_process.err);
246 * Don't bother checking return value, because "emacsclient --version"
247 * seems to always exits with code 1.
249 finish_command(&ec_process);
251 if (!starts_with(buffer.buf, "emacsclient")) {
252 strbuf_release(&buffer);
253 return error(_("Failed to parse emacsclient version."));
256 strbuf_remove(&buffer, 0, strlen("emacsclient"));
257 version = atoi(buffer.buf);
259 if (version < 22) {
260 strbuf_release(&buffer);
261 return error(_("emacsclient version '%d' too old (< 22)."),
262 version);
265 strbuf_release(&buffer);
266 return 0;
269 static void exec_woman_emacs(const char *path, const char *page)
271 if (!check_emacsclient_version()) {
272 /* This works only with emacsclient version >= 22. */
273 struct strbuf man_page = STRBUF_INIT;
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);
284 static void exec_man_konqueror(const char *path, const char *page)
286 const char *display = getenv("DISPLAY");
287 if (display && *display) {
288 struct strbuf man_page = STRBUF_INIT;
289 const char *filename = "kfmclient";
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);
306 static void exec_man_man(const char *path, const char *page)
308 if (!path)
309 path = "man";
310 execlp(path, "man", page, (char *)NULL);
311 warning_errno(_("failed to exec '%s'"), path);
314 static void exec_man_cmd(const char *cmd, const char *page)
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);
323 static void add_man_viewer(const char *name)
325 struct man_viewer_list **p = &man_viewer_list;
327 while (*p)
328 p = &((*p)->next);
329 FLEX_ALLOC_STR(*p, name, name);
332 static int supported_man_viewer(const char *name, size_t len)
334 return (!strncasecmp("man", name, len) ||
335 !strncasecmp("woman", name, len) ||
336 !strncasecmp("konqueror", name, len));
339 static void do_add_man_viewer_info(const char *name,
340 size_t len,
341 const char *value)
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;
350 static int add_man_viewer_path(const char *name,
351 size_t len,
352 const char *value)
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);
361 return 0;
364 static int add_man_viewer_cmd(const char *name,
365 size_t len,
366 const char *value)
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);
375 return 0;
378 static int add_man_viewer_info(const char *var, const char *value)
380 const char *name, *subkey;
381 size_t namelen;
383 if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
384 return 0;
386 if (!strcmp(subkey, "path")) {
387 if (!value)
388 return config_error_nonbool(var);
389 return add_man_viewer_path(name, namelen, value);
391 if (!strcmp(subkey, "cmd")) {
392 if (!value)
393 return config_error_nonbool(var);
394 return add_man_viewer_cmd(name, namelen, value);
397 return 0;
400 static int git_help_config(const char *var, const char *value,
401 const struct config_context *ctx, void *cb)
403 if (!strcmp(var, "help.format")) {
404 if (!value)
405 return config_error_nonbool(var);
406 help_format = parse_help_format(value);
407 return 0;
409 if (!strcmp(var, "help.htmlpath")) {
410 if (!value)
411 return config_error_nonbool(var);
412 html_path = xstrdup(value);
413 return 0;
415 if (!strcmp(var, "man.viewer")) {
416 if (!value)
417 return config_error_nonbool(var);
418 add_man_viewer(value);
419 return 0;
421 if (starts_with(var, "man."))
422 return add_man_viewer_info(var, value);
424 return git_default_config(var, value, ctx, cb);
427 static struct cmdnames main_cmds, other_cmds;
429 static int is_git_command(const char *s)
431 if (is_builtin(s))
432 return 1;
434 load_command_list("git-", &main_cmds, &other_cmds);
435 return is_in_cmdlist(&main_cmds, s) ||
436 is_in_cmdlist(&other_cmds, s);
439 static const char *cmd_to_page(const char *git_cmd)
441 if (!git_cmd)
442 return "git";
443 else if (starts_with(git_cmd, "git"))
444 return git_cmd;
445 else if (is_git_command(git_cmd))
446 return xstrfmt("git-%s", git_cmd);
447 else if (!strcmp("scalar", git_cmd))
448 return xstrdup(git_cmd);
449 else
450 return xstrfmt("git%s", git_cmd);
453 static void setup_man_path(void)
455 struct strbuf new_path = STRBUF_INIT;
456 const char *old_path = getenv("MANPATH");
457 char *git_man_path = system_path(GIT_MAN_PATH);
459 /* We should always put ':' after our path. If there is no
460 * old_path, the ':' at the end will let 'man' to try
461 * system-wide paths after ours to find the manual page. If
462 * there is old_path, we need ':' as delimiter. */
463 strbuf_addstr(&new_path, git_man_path);
464 strbuf_addch(&new_path, ':');
465 if (old_path)
466 strbuf_addstr(&new_path, old_path);
468 free(git_man_path);
469 setenv("MANPATH", new_path.buf, 1);
471 strbuf_release(&new_path);
474 static void exec_viewer(const char *name, const char *page)
476 const char *info = get_man_viewer_info(name);
478 if (!strcasecmp(name, "man"))
479 exec_man_man(info, page);
480 else if (!strcasecmp(name, "woman"))
481 exec_woman_emacs(info, page);
482 else if (!strcasecmp(name, "konqueror"))
483 exec_man_konqueror(info, page);
484 else if (info)
485 exec_man_cmd(info, page);
486 else
487 warning(_("'%s': unknown man viewer."), name);
490 static void show_man_page(const char *page)
492 struct man_viewer_list *viewer;
493 const char *fallback = getenv("GIT_MAN_VIEWER");
495 setup_man_path();
496 for (viewer = man_viewer_list; viewer; viewer = viewer->next)
498 exec_viewer(viewer->name, page); /* will return when unable */
500 if (fallback)
501 exec_viewer(fallback, page);
502 exec_viewer("man", page);
503 die(_("no man viewer handled the request"));
506 static void show_info_page(const char *page)
508 setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
509 execlp("info", "info", "gitman", page, (char *)NULL);
510 die(_("no info viewer handled the request"));
513 static void get_html_page_path(struct strbuf *page_path, const char *page)
515 struct stat st;
516 char *to_free = NULL;
518 if (!html_path)
519 html_path = to_free = system_path(GIT_HTML_PATH);
522 * Check that the page we're looking for exists.
524 if (!strstr(html_path, "://")) {
525 if (stat(mkpath("%s/%s.html", html_path, page), &st)
526 || !S_ISREG(st.st_mode))
527 die("'%s/%s.html': documentation file not found.",
528 html_path, page);
531 strbuf_init(page_path, 0);
532 strbuf_addf(page_path, "%s/%s.html", html_path, page);
533 free(to_free);
536 static void open_html(const char *path)
538 execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
541 static void show_html_page(const char *page)
543 struct strbuf page_path; /* it leaks but we exec bellow */
545 get_html_page_path(&page_path, page);
547 open_html(page_path.buf);
550 static const char *check_git_cmd(const char* cmd)
552 char *alias;
554 if (is_git_command(cmd))
555 return cmd;
557 alias = alias_lookup(cmd);
558 if (alias) {
559 const char **argv;
560 int count;
563 * handle_builtin() in git.c rewrites "git cmd --help"
564 * to "git help --exclude-guides cmd", so we can use
565 * exclude_guides to distinguish "git cmd --help" from
566 * "git help cmd". In the latter case, or if cmd is an
567 * alias for a shell command, just print the alias
568 * definition.
570 if (!exclude_guides || alias[0] == '!') {
571 printf_ln(_("'%s' is aliased to '%s'"), cmd, alias);
572 free(alias);
573 exit(0);
576 * Otherwise, we pretend that the command was "git
577 * word0 --help". We use split_cmdline() to get the
578 * first word of the alias, to ensure that we use the
579 * same rules as when the alias is actually
580 * used. split_cmdline() modifies alias in-place.
582 fprintf_ln(stderr, _("'%s' is aliased to '%s'"), cmd, alias);
583 count = split_cmdline(alias, &argv);
584 if (count < 0)
585 die(_("bad alias.%s string: %s"), cmd,
586 split_cmdline_strerror(count));
587 free(argv);
588 UNLEAK(alias);
589 return alias;
592 if (exclude_guides)
593 return help_unknown_cmd(cmd);
595 return cmd;
598 static void no_help_format(const char *opt_mode, enum help_format fmt)
600 const char *opt_fmt;
602 switch (fmt) {
603 case HELP_FORMAT_NONE:
604 return;
605 case HELP_FORMAT_MAN:
606 opt_fmt = "--man";
607 break;
608 case HELP_FORMAT_INFO:
609 opt_fmt = "--info";
610 break;
611 case HELP_FORMAT_WEB:
612 opt_fmt = "--web";
613 break;
614 default:
615 BUG("unreachable");
618 usage_msg_optf(_("options '%s' and '%s' cannot be used together"),
619 builtin_help_usage, builtin_help_options, opt_mode,
620 opt_fmt);
623 static void opt_mode_usage(int argc, const char *opt_mode,
624 enum help_format fmt)
626 if (argc)
627 usage_msg_optf(_("the '%s' option doesn't take any non-option arguments"),
628 builtin_help_usage, builtin_help_options,
629 opt_mode);
631 no_help_format(opt_mode, fmt);
634 int cmd_help(int argc, const char **argv, const char *prefix)
636 int nongit;
637 enum help_format parsed_help_format;
638 const char *page;
640 argc = parse_options(argc, argv, prefix, builtin_help_options,
641 builtin_help_usage, 0);
642 parsed_help_format = help_format;
644 if (cmd_mode != HELP_ACTION_ALL &&
645 (show_external_commands >= 0 ||
646 show_aliases >= 0))
647 usage_msg_opt(_("the '--no-[external-commands|aliases]' options can only be used with '--all'"),
648 builtin_help_usage, builtin_help_options);
650 switch (cmd_mode) {
651 case HELP_ACTION_ALL:
652 opt_mode_usage(argc, "--all", help_format);
653 if (verbose) {
654 setup_pager();
655 list_all_cmds_help(show_external_commands,
656 show_aliases);
657 return 0;
659 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
660 load_command_list("git-", &main_cmds, &other_cmds);
661 list_commands(&main_cmds, &other_cmds);
662 printf("%s\n", _(git_more_info_string));
663 break;
664 case HELP_ACTION_GUIDES:
665 opt_mode_usage(argc, "--guides", help_format);
666 list_guides_help();
667 printf("%s\n", _(git_more_info_string));
668 return 0;
669 case HELP_ACTION_CONFIG_FOR_COMPLETION:
670 opt_mode_usage(argc, "--config-for-completion", help_format);
671 list_config_help(SHOW_CONFIG_VARS);
672 return 0;
673 case HELP_ACTION_USER_INTERFACES:
674 opt_mode_usage(argc, "--user-interfaces", help_format);
675 list_user_interfaces_help();
676 return 0;
677 case HELP_ACTION_DEVELOPER_INTERFACES:
678 opt_mode_usage(argc, "--developer-interfaces", help_format);
679 list_developer_interfaces_help();
680 return 0;
681 case HELP_ACTION_CONFIG_SECTIONS_FOR_COMPLETION:
682 opt_mode_usage(argc, "--config-sections-for-completion",
683 help_format);
684 list_config_help(SHOW_CONFIG_SECTIONS);
685 return 0;
686 case HELP_ACTION_CONFIG:
687 opt_mode_usage(argc, "--config", help_format);
688 setup_pager();
689 list_config_help(SHOW_CONFIG_HUMAN);
690 printf("\n%s\n", _("'git help config' for more information"));
691 return 0;
694 if (!argv[0]) {
695 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
696 list_common_cmds_help();
697 printf("\n%s\n", _(git_more_info_string));
698 return 0;
701 setup_git_directory_gently(&nongit);
702 git_config(git_help_config, NULL);
704 if (parsed_help_format != HELP_FORMAT_NONE)
705 help_format = parsed_help_format;
706 if (help_format == HELP_FORMAT_NONE)
707 help_format = parse_help_format(DEFAULT_HELP_FORMAT);
709 argv[0] = check_git_cmd(argv[0]);
711 page = cmd_to_page(argv[0]);
712 switch (help_format) {
713 case HELP_FORMAT_NONE:
714 case HELP_FORMAT_MAN:
715 show_man_page(page);
716 break;
717 case HELP_FORMAT_INFO:
718 show_info_page(page);
719 break;
720 case HELP_FORMAT_WEB:
721 show_html_page(page);
722 break;
725 return 0;