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