help: Do not unnecessarily look for a repository
[git/git.git] / builtin-help.c
CommitLineData
3d78d1f1
MV
1/*
2 * builtin-help.c
3 *
4 * Builtin help command
5 */
6#include "cache.h"
7#include "builtin.h"
8#include "exec_cmd.h"
9#include "common-cmds.h"
10#include "parse-options.h"
11#include "run-command.h"
12#include "help.h"
13
14static struct man_viewer_list {
15 struct man_viewer_list *next;
16 char name[FLEX_ARRAY];
17} *man_viewer_list;
18
19static struct man_viewer_info_list {
20 struct man_viewer_info_list *next;
21 const char *info;
22 char name[FLEX_ARRAY];
23} *man_viewer_info_list;
24
25enum help_format {
26 HELP_FORMAT_MAN,
27 HELP_FORMAT_INFO,
28 HELP_FORMAT_WEB,
29};
30
31static int show_all = 0;
32static enum help_format help_format = HELP_FORMAT_MAN;
33static struct option builtin_help_options[] = {
34 OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
35 OPT_SET_INT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
36 OPT_SET_INT('w', "web", &help_format, "show manual in web browser",
37 HELP_FORMAT_WEB),
38 OPT_SET_INT('i', "info", &help_format, "show info page",
39 HELP_FORMAT_INFO),
40 OPT_END(),
41};
42
43static const char * const builtin_help_usage[] = {
44 "git help [--all] [--man|--web|--info] [command]",
45 NULL
46};
47
48static enum help_format parse_help_format(const char *format)
49{
50 if (!strcmp(format, "man"))
51 return HELP_FORMAT_MAN;
52 if (!strcmp(format, "info"))
53 return HELP_FORMAT_INFO;
54 if (!strcmp(format, "web") || !strcmp(format, "html"))
55 return HELP_FORMAT_WEB;
56 die("unrecognized help format '%s'", format);
57}
58
59static const char *get_man_viewer_info(const char *name)
60{
61 struct man_viewer_info_list *viewer;
62
63 for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
64 {
65 if (!strcasecmp(name, viewer->name))
66 return viewer->info;
67 }
68 return NULL;
69}
70
71static int check_emacsclient_version(void)
72{
73 struct strbuf buffer = STRBUF_INIT;
74 struct child_process ec_process;
75 const char *argv_ec[] = { "emacsclient", "--version", NULL };
76 int version;
77
78 /* emacsclient prints its version number on stderr */
79 memset(&ec_process, 0, sizeof(ec_process));
80 ec_process.argv = argv_ec;
81 ec_process.err = -1;
82 ec_process.stdout_to_stderr = 1;
4e2715fb
JS
83 if (start_command(&ec_process))
84 return error("Failed to start emacsclient.");
85
3d78d1f1
MV
86 strbuf_read(&buffer, ec_process.err, 20);
87 close(ec_process.err);
88
89 /*
90 * Don't bother checking return value, because "emacsclient --version"
91 * seems to always exits with code 1.
92 */
93 finish_command(&ec_process);
94
95 if (prefixcmp(buffer.buf, "emacsclient")) {
3d78d1f1 96 strbuf_release(&buffer);
4e2715fb 97 return error("Failed to parse emacsclient version.");
3d78d1f1
MV
98 }
99
100 strbuf_remove(&buffer, 0, strlen("emacsclient"));
101 version = atoi(buffer.buf);
102
103 if (version < 22) {
3d78d1f1 104 strbuf_release(&buffer);
4e2715fb
JS
105 return error("emacsclient version '%d' too old (< 22).",
106 version);
3d78d1f1
MV
107 }
108
109 strbuf_release(&buffer);
110 return 0;
111}
112
4b25d091 113static void exec_woman_emacs(const char *path, const char *page)
3d78d1f1
MV
114{
115 if (!check_emacsclient_version()) {
116 /* This works only with emacsclient version >= 22. */
117 struct strbuf man_page = STRBUF_INIT;
118
119 if (!path)
120 path = "emacsclient";
121 strbuf_addf(&man_page, "(woman \"%s\")", page);
122 execlp(path, "emacsclient", "-e", man_page.buf, NULL);
123 warning("failed to exec '%s': %s", path, strerror(errno));
124 }
125}
126
4b25d091 127static void exec_man_konqueror(const char *path, const char *page)
3d78d1f1
MV
128{
129 const char *display = getenv("DISPLAY");
130 if (display && *display) {
131 struct strbuf man_page = STRBUF_INIT;
132 const char *filename = "kfmclient";
133
134 /* It's simpler to launch konqueror using kfmclient. */
135 if (path) {
136 const char *file = strrchr(path, '/');
137 if (file && !strcmp(file + 1, "konqueror")) {
138 char *new = xstrdup(path);
139 char *dest = strrchr(new, '/');
140
141 /* strlen("konqueror") == strlen("kfmclient") */
142 strcpy(dest + 1, "kfmclient");
143 path = new;
144 }
145 if (file)
146 filename = file;
147 } else
148 path = "kfmclient";
149 strbuf_addf(&man_page, "man:%s(1)", page);
150 execlp(path, filename, "newTab", man_page.buf, NULL);
151 warning("failed to exec '%s': %s", path, strerror(errno));
152 }
153}
154
4b25d091 155static void exec_man_man(const char *path, const char *page)
3d78d1f1
MV
156{
157 if (!path)
158 path = "man";
159 execlp(path, "man", page, NULL);
160 warning("failed to exec '%s': %s", path, strerror(errno));
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("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
168 warning("failed to exec '%s': %s", cmd, strerror(errno));
169}
170
171static void add_man_viewer(const char *name)
172{
173 struct man_viewer_list **p = &man_viewer_list;
174 size_t len = strlen(name);
175
176 while (*p)
177 p = &((*p)->next);
178 *p = xcalloc(1, (sizeof(**p) + len + 1));
179 strncpy((*p)->name, name, len);
180}
181
182static int supported_man_viewer(const char *name, size_t len)
183{
184 return (!strncasecmp("man", name, len) ||
185 !strncasecmp("woman", name, len) ||
186 !strncasecmp("konqueror", name, len));
187}
188
189static void do_add_man_viewer_info(const char *name,
190 size_t len,
191 const char *value)
192{
193 struct man_viewer_info_list *new = xcalloc(1, sizeof(*new) + len + 1);
194
195 strncpy(new->name, name, len);
196 new->info = xstrdup(value);
197 new->next = man_viewer_info_list;
198 man_viewer_info_list = new;
199}
200
201static int add_man_viewer_path(const char *name,
202 size_t len,
203 const char *value)
204{
205 if (supported_man_viewer(name, len))
206 do_add_man_viewer_info(name, len, value);
207 else
208 warning("'%s': path for unsupported man viewer.\n"
209 "Please consider using 'man.<tool>.cmd' instead.",
210 name);
211
212 return 0;
213}
214
215static int add_man_viewer_cmd(const char *name,
216 size_t len,
217 const char *value)
218{
219 if (supported_man_viewer(name, len))
220 warning("'%s': cmd for supported man viewer.\n"
221 "Please consider using 'man.<tool>.path' instead.",
222 name);
223 else
224 do_add_man_viewer_info(name, len, value);
225
226 return 0;
227}
228
229static int add_man_viewer_info(const char *var, const char *value)
230{
231 const char *name = var + 4;
232 const char *subkey = strrchr(name, '.');
233
234 if (!subkey)
178b513e 235 return 0;
3d78d1f1
MV
236
237 if (!strcmp(subkey, ".path")) {
238 if (!value)
239 return config_error_nonbool(var);
240 return add_man_viewer_path(name, subkey - name, value);
241 }
242 if (!strcmp(subkey, ".cmd")) {
243 if (!value)
244 return config_error_nonbool(var);
245 return add_man_viewer_cmd(name, subkey - name, value);
246 }
247
3d78d1f1
MV
248 return 0;
249}
250
251static int git_help_config(const char *var, const char *value, void *cb)
252{
253 if (!strcmp(var, "help.format")) {
254 if (!value)
255 return config_error_nonbool(var);
256 help_format = parse_help_format(value);
257 return 0;
258 }
259 if (!strcmp(var, "man.viewer")) {
260 if (!value)
261 return config_error_nonbool(var);
262 add_man_viewer(value);
263 return 0;
264 }
265 if (!prefixcmp(var, "man."))
266 return add_man_viewer_info(var, value);
267
268 return git_default_config(var, value, cb);
269}
270
c7371e99 271static struct cmdnames main_cmds, other_cmds;
3d78d1f1
MV
272
273void list_common_cmds_help(void)
274{
275 int i, longest = 0;
276
277 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
278 if (longest < strlen(common_cmds[i].name))
279 longest = strlen(common_cmds[i].name);
280 }
281
282 puts("The most commonly used git commands are:");
283 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
284 printf(" %s ", common_cmds[i].name);
285 mput_char(' ', longest - strlen(common_cmds[i].name));
286 puts(common_cmds[i].help);
287 }
288}
289
290static int is_git_command(const char *s)
291{
292 return is_in_cmdlist(&main_cmds, s) ||
293 is_in_cmdlist(&other_cmds, s);
294}
295
296static const char *prepend(const char *prefix, const char *cmd)
297{
298 size_t pre_len = strlen(prefix);
299 size_t cmd_len = strlen(cmd);
300 char *p = xmalloc(pre_len + cmd_len + 1);
301 memcpy(p, prefix, pre_len);
302 strcpy(p + pre_len, cmd);
303 return p;
304}
305
306static const char *cmd_to_page(const char *git_cmd)
307{
308 if (!git_cmd)
309 return "git";
310 else if (!prefixcmp(git_cmd, "git"))
311 return git_cmd;
312 else if (is_git_command(git_cmd))
313 return prepend("git-", git_cmd);
314 else
315 return prepend("git", git_cmd);
316}
317
318static void setup_man_path(void)
319{
f285a2d7 320 struct strbuf new_path = STRBUF_INIT;
3d78d1f1
MV
321 const char *old_path = getenv("MANPATH");
322
3d78d1f1
MV
323 /* We should always put ':' after our path. If there is no
324 * old_path, the ':' at the end will let 'man' to try
325 * system-wide paths after ours to find the manual page. If
326 * there is old_path, we need ':' as delimiter. */
026fa0d5 327 strbuf_addstr(&new_path, system_path(GIT_MAN_PATH));
3d78d1f1
MV
328 strbuf_addch(&new_path, ':');
329 if (old_path)
330 strbuf_addstr(&new_path, old_path);
331
332 setenv("MANPATH", new_path.buf, 1);
333
334 strbuf_release(&new_path);
335}
336
337static void exec_viewer(const char *name, const char *page)
338{
339 const char *info = get_man_viewer_info(name);
340
341 if (!strcasecmp(name, "man"))
342 exec_man_man(info, page);
343 else if (!strcasecmp(name, "woman"))
344 exec_woman_emacs(info, page);
345 else if (!strcasecmp(name, "konqueror"))
346 exec_man_konqueror(info, page);
347 else if (info)
348 exec_man_cmd(info, page);
349 else
350 warning("'%s': unknown man viewer.", name);
351}
352
353static void show_man_page(const char *git_cmd)
354{
355 struct man_viewer_list *viewer;
356 const char *page = cmd_to_page(git_cmd);
5059a427 357 const char *fallback = getenv("GIT_MAN_VIEWER");
3d78d1f1
MV
358
359 setup_man_path();
360 for (viewer = man_viewer_list; viewer; viewer = viewer->next)
361 {
362 exec_viewer(viewer->name, page); /* will return when unable */
363 }
5059a427
RF
364 if (fallback)
365 exec_viewer(fallback, page);
3d78d1f1
MV
366 exec_viewer("man", page);
367 die("no man viewer handled the request");
368}
369
370static void show_info_page(const char *git_cmd)
371{
372 const char *page = cmd_to_page(git_cmd);
026fa0d5 373 setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
3d78d1f1 374 execlp("info", "info", "gitman", page, NULL);
a29aa47d 375 die("no info viewer handled the request");
3d78d1f1
MV
376}
377
378static void get_html_page_path(struct strbuf *page_path, const char *page)
379{
380 struct stat st;
381 const char *html_path = system_path(GIT_HTML_PATH);
382
383 /* Check that we have a git documentation directory. */
384 if (stat(mkpath("%s/git.html", html_path), &st)
385 || !S_ISREG(st.st_mode))
386 die("'%s': not a documentation directory.", html_path);
387
388 strbuf_init(page_path, 0);
389 strbuf_addf(page_path, "%s/%s.html", html_path, page);
390}
391
392/*
393 * If open_html is not defined in a platform-specific way (see for
394 * example compat/mingw.h), we use the script web--browse to display
395 * HTML.
396 */
397#ifndef open_html
2af202be 398static void open_html(const char *path)
3d78d1f1
MV
399{
400 execl_git_cmd("web--browse", "-c", "help.browser", path, NULL);
401}
402#endif
403
404static void show_html_page(const char *git_cmd)
405{
406 const char *page = cmd_to_page(git_cmd);
407 struct strbuf page_path; /* it leaks but we exec bellow */
408
409 get_html_page_path(&page_path, page);
410
411 open_html(page_path.buf);
412}
413
414int cmd_help(int argc, const char **argv, const char *prefix)
415{
416 int nongit;
417 const char *alias;
e321180e 418 load_command_list("git-", &main_cmds, &other_cmds);
3d78d1f1 419
37782920 420 argc = parse_options(argc, argv, prefix, builtin_help_options,
3d78d1f1
MV
421 builtin_help_usage, 0);
422
423 if (show_all) {
424 printf("usage: %s\n\n", git_usage_string);
e321180e 425 list_commands("git commands", &main_cmds, &other_cmds);
3d78d1f1
MV
426 printf("%s\n", git_more_info_string);
427 return 0;
428 }
429
430 if (!argv[0]) {
431 printf("usage: %s\n\n", git_usage_string);
432 list_common_cmds_help();
433 printf("\n%s\n", git_more_info_string);
434 return 0;
435 }
436
af6fbf9f
DA
437 setup_git_directory_gently(&nongit);
438 git_config(git_help_config, NULL);
439
3d78d1f1
MV
440 alias = alias_lookup(argv[0]);
441 if (alias && !is_git_command(argv[0])) {
442 printf("`git %s' is aliased to `%s'\n", argv[0], alias);
443 return 0;
444 }
445
446 switch (help_format) {
447 case HELP_FORMAT_MAN:
448 show_man_page(argv[0]);
449 break;
450 case HELP_FORMAT_INFO:
451 show_info_page(argv[0]);
452 break;
453 case HELP_FORMAT_WEB:
454 show_html_page(argv[0]);
455 break;
456 }
457
458 return 0;
459}