Merge branch 'ph/builtin-srcs-are-in-subdir-these-days' into maint
[git/git.git] / builtin / help.c
1 /*
2 * Builtin help command
3 */
4 #include "cache.h"
5 #include "builtin.h"
6 #include "exec_cmd.h"
7 #include "parse-options.h"
8 #include "run-command.h"
9 #include "column.h"
10 #include "help.h"
11
12 #ifndef DEFAULT_HELP_FORMAT
13 #define DEFAULT_HELP_FORMAT "man"
14 #endif
15
16 static struct man_viewer_list {
17 struct man_viewer_list *next;
18 char name[FLEX_ARRAY];
19 } *man_viewer_list;
20
21 static struct man_viewer_info_list {
22 struct man_viewer_info_list *next;
23 const char *info;
24 char name[FLEX_ARRAY];
25 } *man_viewer_info_list;
26
27 enum help_format {
28 HELP_FORMAT_NONE,
29 HELP_FORMAT_MAN,
30 HELP_FORMAT_INFO,
31 HELP_FORMAT_WEB
32 };
33
34 static const char *html_path;
35
36 static int show_all = 0;
37 static int show_guides = 0;
38 static unsigned int colopts;
39 static enum help_format help_format = HELP_FORMAT_NONE;
40 static struct option builtin_help_options[] = {
41 OPT_BOOL('a', "all", &show_all, N_("print all available commands")),
42 OPT_BOOL('g', "guides", &show_guides, N_("print list of useful guides")),
43 OPT_SET_INT('m', "man", &help_format, N_("show man page"), HELP_FORMAT_MAN),
44 OPT_SET_INT('w', "web", &help_format, N_("show manual in web browser"),
45 HELP_FORMAT_WEB),
46 OPT_SET_INT('i', "info", &help_format, N_("show info page"),
47 HELP_FORMAT_INFO),
48 OPT_END(),
49 };
50
51 static const char * const builtin_help_usage[] = {
52 N_("git help [--all] [--guides] [--man|--web|--info] [command]"),
53 NULL
54 };
55
56 static enum help_format parse_help_format(const char *format)
57 {
58 if (!strcmp(format, "man"))
59 return HELP_FORMAT_MAN;
60 if (!strcmp(format, "info"))
61 return HELP_FORMAT_INFO;
62 if (!strcmp(format, "web") || !strcmp(format, "html"))
63 return HELP_FORMAT_WEB;
64 die(_("unrecognized help format '%s'"), format);
65 }
66
67 static const char *get_man_viewer_info(const char *name)
68 {
69 struct man_viewer_info_list *viewer;
70
71 for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
72 {
73 if (!strcasecmp(name, viewer->name))
74 return viewer->info;
75 }
76 return NULL;
77 }
78
79 static int check_emacsclient_version(void)
80 {
81 struct strbuf buffer = STRBUF_INIT;
82 struct child_process ec_process;
83 const char *argv_ec[] = { "emacsclient", "--version", NULL };
84 int version;
85
86 /* emacsclient prints its version number on stderr */
87 memset(&ec_process, 0, sizeof(ec_process));
88 ec_process.argv = argv_ec;
89 ec_process.err = -1;
90 ec_process.stdout_to_stderr = 1;
91 if (start_command(&ec_process))
92 return error(_("Failed to start emacsclient."));
93
94 strbuf_read(&buffer, ec_process.err, 20);
95 close(ec_process.err);
96
97 /*
98 * Don't bother checking return value, because "emacsclient --version"
99 * seems to always exits with code 1.
100 */
101 finish_command(&ec_process);
102
103 if (prefixcmp(buffer.buf, "emacsclient")) {
104 strbuf_release(&buffer);
105 return error(_("Failed to parse emacsclient version."));
106 }
107
108 strbuf_remove(&buffer, 0, strlen("emacsclient"));
109 version = atoi(buffer.buf);
110
111 if (version < 22) {
112 strbuf_release(&buffer);
113 return error(_("emacsclient version '%d' too old (< 22)."),
114 version);
115 }
116
117 strbuf_release(&buffer);
118 return 0;
119 }
120
121 static void exec_woman_emacs(const char *path, const char *page)
122 {
123 if (!check_emacsclient_version()) {
124 /* This works only with emacsclient version >= 22. */
125 struct strbuf man_page = STRBUF_INIT;
126
127 if (!path)
128 path = "emacsclient";
129 strbuf_addf(&man_page, "(woman \"%s\")", page);
130 execlp(path, "emacsclient", "-e", man_page.buf, (char *)NULL);
131 warning(_("failed to exec '%s': %s"), path, strerror(errno));
132 }
133 }
134
135 static void exec_man_konqueror(const char *path, const char *page)
136 {
137 const char *display = getenv("DISPLAY");
138 if (display && *display) {
139 struct strbuf man_page = STRBUF_INIT;
140 const char *filename = "kfmclient";
141
142 /* It's simpler to launch konqueror using kfmclient. */
143 if (path) {
144 const char *file = strrchr(path, '/');
145 if (file && !strcmp(file + 1, "konqueror")) {
146 char *new = xstrdup(path);
147 char *dest = strrchr(new, '/');
148
149 /* strlen("konqueror") == strlen("kfmclient") */
150 strcpy(dest + 1, "kfmclient");
151 path = new;
152 }
153 if (file)
154 filename = file;
155 } else
156 path = "kfmclient";
157 strbuf_addf(&man_page, "man:%s(1)", page);
158 execlp(path, filename, "newTab", man_page.buf, (char *)NULL);
159 warning(_("failed to exec '%s': %s"), path, strerror(errno));
160 }
161 }
162
163 static void exec_man_man(const char *path, const char *page)
164 {
165 if (!path)
166 path = "man";
167 execlp(path, "man", page, (char *)NULL);
168 warning(_("failed to exec '%s': %s"), path, strerror(errno));
169 }
170
171 static void exec_man_cmd(const char *cmd, const char *page)
172 {
173 struct strbuf shell_cmd = STRBUF_INIT;
174 strbuf_addf(&shell_cmd, "%s %s", cmd, page);
175 execl("/bin/sh", "sh", "-c", shell_cmd.buf, (char *)NULL);
176 warning(_("failed to exec '%s': %s"), cmd, strerror(errno));
177 }
178
179 static void add_man_viewer(const char *name)
180 {
181 struct man_viewer_list **p = &man_viewer_list;
182 size_t len = strlen(name);
183
184 while (*p)
185 p = &((*p)->next);
186 *p = xcalloc(1, (sizeof(**p) + len + 1));
187 strncpy((*p)->name, name, len);
188 }
189
190 static int supported_man_viewer(const char *name, size_t len)
191 {
192 return (!strncasecmp("man", name, len) ||
193 !strncasecmp("woman", name, len) ||
194 !strncasecmp("konqueror", name, len));
195 }
196
197 static void do_add_man_viewer_info(const char *name,
198 size_t len,
199 const char *value)
200 {
201 struct man_viewer_info_list *new = xcalloc(1, sizeof(*new) + len + 1);
202
203 strncpy(new->name, name, len);
204 new->info = xstrdup(value);
205 new->next = man_viewer_info_list;
206 man_viewer_info_list = new;
207 }
208
209 static int add_man_viewer_path(const char *name,
210 size_t len,
211 const char *value)
212 {
213 if (supported_man_viewer(name, len))
214 do_add_man_viewer_info(name, len, value);
215 else
216 warning(_("'%s': path for unsupported man viewer.\n"
217 "Please consider using 'man.<tool>.cmd' instead."),
218 name);
219
220 return 0;
221 }
222
223 static int add_man_viewer_cmd(const char *name,
224 size_t len,
225 const char *value)
226 {
227 if (supported_man_viewer(name, len))
228 warning(_("'%s': cmd for supported man viewer.\n"
229 "Please consider using 'man.<tool>.path' instead."),
230 name);
231 else
232 do_add_man_viewer_info(name, len, value);
233
234 return 0;
235 }
236
237 static int add_man_viewer_info(const char *var, const char *value)
238 {
239 const char *name, *subkey;
240 int namelen;
241
242 if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
243 return 0;
244
245 if (!strcmp(subkey, "path")) {
246 if (!value)
247 return config_error_nonbool(var);
248 return add_man_viewer_path(name, namelen, value);
249 }
250 if (!strcmp(subkey, "cmd")) {
251 if (!value)
252 return config_error_nonbool(var);
253 return add_man_viewer_cmd(name, namelen, value);
254 }
255
256 return 0;
257 }
258
259 static int git_help_config(const char *var, const char *value, void *cb)
260 {
261 if (!prefixcmp(var, "column."))
262 return git_column_config(var, value, "help", &colopts);
263 if (!strcmp(var, "help.format")) {
264 if (!value)
265 return config_error_nonbool(var);
266 help_format = parse_help_format(value);
267 return 0;
268 }
269 if (!strcmp(var, "help.htmlpath")) {
270 if (!value)
271 return config_error_nonbool(var);
272 html_path = xstrdup(value);
273 return 0;
274 }
275 if (!strcmp(var, "man.viewer")) {
276 if (!value)
277 return config_error_nonbool(var);
278 add_man_viewer(value);
279 return 0;
280 }
281 if (!prefixcmp(var, "man."))
282 return add_man_viewer_info(var, value);
283
284 return git_default_config(var, value, cb);
285 }
286
287 static struct cmdnames main_cmds, other_cmds;
288
289 static int is_git_command(const char *s)
290 {
291 return is_in_cmdlist(&main_cmds, s) ||
292 is_in_cmdlist(&other_cmds, s);
293 }
294
295 static const char *prepend(const char *prefix, const char *cmd)
296 {
297 size_t pre_len = strlen(prefix);
298 size_t cmd_len = strlen(cmd);
299 char *p = xmalloc(pre_len + cmd_len + 1);
300 memcpy(p, prefix, pre_len);
301 strcpy(p + pre_len, cmd);
302 return p;
303 }
304
305 static const char *cmd_to_page(const char *git_cmd)
306 {
307 if (!git_cmd)
308 return "git";
309 else if (!prefixcmp(git_cmd, "git"))
310 return git_cmd;
311 else if (is_git_command(git_cmd))
312 return prepend("git-", git_cmd);
313 else
314 return prepend("git", git_cmd);
315 }
316
317 static void setup_man_path(void)
318 {
319 struct strbuf new_path = STRBUF_INIT;
320 const char *old_path = getenv("MANPATH");
321
322 /* We should always put ':' after our path. If there is no
323 * old_path, the ':' at the end will let 'man' to try
324 * system-wide paths after ours to find the manual page. If
325 * there is old_path, we need ':' as delimiter. */
326 strbuf_addstr(&new_path, system_path(GIT_MAN_PATH));
327 strbuf_addch(&new_path, ':');
328 if (old_path)
329 strbuf_addstr(&new_path, old_path);
330
331 setenv("MANPATH", new_path.buf, 1);
332
333 strbuf_release(&new_path);
334 }
335
336 static void exec_viewer(const char *name, const char *page)
337 {
338 const char *info = get_man_viewer_info(name);
339
340 if (!strcasecmp(name, "man"))
341 exec_man_man(info, page);
342 else if (!strcasecmp(name, "woman"))
343 exec_woman_emacs(info, page);
344 else if (!strcasecmp(name, "konqueror"))
345 exec_man_konqueror(info, page);
346 else if (info)
347 exec_man_cmd(info, page);
348 else
349 warning(_("'%s': unknown man viewer."), name);
350 }
351
352 static void show_man_page(const char *git_cmd)
353 {
354 struct man_viewer_list *viewer;
355 const char *page = cmd_to_page(git_cmd);
356 const char *fallback = getenv("GIT_MAN_VIEWER");
357
358 setup_man_path();
359 for (viewer = man_viewer_list; viewer; viewer = viewer->next)
360 {
361 exec_viewer(viewer->name, page); /* will return when unable */
362 }
363 if (fallback)
364 exec_viewer(fallback, page);
365 exec_viewer("man", page);
366 die(_("no man viewer handled the request"));
367 }
368
369 static void show_info_page(const char *git_cmd)
370 {
371 const char *page = cmd_to_page(git_cmd);
372 setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
373 execlp("info", "info", "gitman", page, (char *)NULL);
374 die(_("no info viewer handled the request"));
375 }
376
377 static void get_html_page_path(struct strbuf *page_path, const char *page)
378 {
379 struct stat st;
380 if (!html_path)
381 html_path = system_path(GIT_HTML_PATH);
382
383 /* Check that we have a git documentation directory. */
384 if (!strstr(html_path, "://")) {
385 if (stat(mkpath("%s/git.html", html_path), &st)
386 || !S_ISREG(st.st_mode))
387 die("'%s': not a documentation directory.", html_path);
388 }
389
390 strbuf_init(page_path, 0);
391 strbuf_addf(page_path, "%s/%s.html", html_path, page);
392 }
393
394 /*
395 * If open_html is not defined in a platform-specific way (see for
396 * example compat/mingw.h), we use the script web--browse to display
397 * HTML.
398 */
399 #ifndef open_html
400 static void open_html(const char *path)
401 {
402 execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
403 }
404 #endif
405
406 static void show_html_page(const char *git_cmd)
407 {
408 const char *page = cmd_to_page(git_cmd);
409 struct strbuf page_path; /* it leaks but we exec bellow */
410
411 get_html_page_path(&page_path, page);
412
413 open_html(page_path.buf);
414 }
415
416 static struct {
417 const char *name;
418 const char *help;
419 } common_guides[] = {
420 { "attributes", N_("Defining attributes per path") },
421 { "glossary", N_("A Git glossary") },
422 { "ignore", N_("Specifies intentionally untracked files to ignore") },
423 { "modules", N_("Defining submodule properties") },
424 { "revisions", N_("Specifying revisions and ranges for Git") },
425 { "tutorial", N_("A tutorial introduction to Git (for version 1.5.1 or newer)") },
426 { "workflows", N_("An overview of recommended workflows with Git") },
427 };
428
429 static void list_common_guides_help(void)
430 {
431 int i, longest = 0;
432
433 for (i = 0; i < ARRAY_SIZE(common_guides); i++) {
434 if (longest < strlen(common_guides[i].name))
435 longest = strlen(common_guides[i].name);
436 }
437
438 puts(_("The common Git guides are:\n"));
439 for (i = 0; i < ARRAY_SIZE(common_guides); i++) {
440 printf(" %s ", common_guides[i].name);
441 mput_char(' ', longest - strlen(common_guides[i].name));
442 puts(_(common_guides[i].help));
443 }
444 putchar('\n');
445 }
446
447 int cmd_help(int argc, const char **argv, const char *prefix)
448 {
449 int nongit;
450 const char *alias;
451 enum help_format parsed_help_format;
452 load_command_list("git-", &main_cmds, &other_cmds);
453
454 argc = parse_options(argc, argv, prefix, builtin_help_options,
455 builtin_help_usage, 0);
456 parsed_help_format = help_format;
457
458 if (show_all) {
459 git_config(git_help_config, NULL);
460 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
461 list_commands(colopts, &main_cmds, &other_cmds);
462 }
463
464 if (show_guides)
465 list_common_guides_help();
466
467 if (show_all || show_guides) {
468 printf("%s\n", _(git_more_info_string));
469 /*
470 * We're done. Ignore any remaining args
471 */
472 return 0;
473 }
474
475 if (!argv[0]) {
476 printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
477 list_common_cmds_help();
478 printf("\n%s\n", _(git_more_info_string));
479 return 0;
480 }
481
482 setup_git_directory_gently(&nongit);
483 git_config(git_help_config, NULL);
484
485 if (parsed_help_format != HELP_FORMAT_NONE)
486 help_format = parsed_help_format;
487 if (help_format == HELP_FORMAT_NONE)
488 help_format = parse_help_format(DEFAULT_HELP_FORMAT);
489
490 alias = alias_lookup(argv[0]);
491 if (alias && !is_git_command(argv[0])) {
492 printf_ln(_("`git %s' is aliased to `%s'"), argv[0], alias);
493 return 0;
494 }
495
496 switch (help_format) {
497 case HELP_FORMAT_NONE:
498 case HELP_FORMAT_MAN:
499 show_man_page(argv[0]);
500 break;
501 case HELP_FORMAT_INFO:
502 show_info_page(argv[0]);
503 break;
504 case HELP_FORMAT_WEB:
505 show_html_page(argv[0]);
506 break;
507 }
508
509 return 0;
510 }