Fix a bunch of pointer declarations (codestyle)
[git/git.git] / builtin-help.c
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
14 static struct man_viewer_list {
15 struct man_viewer_list *next;
16 char name[FLEX_ARRAY];
17 } *man_viewer_list;
18
19 static 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
25 enum help_format {
26 HELP_FORMAT_MAN,
27 HELP_FORMAT_INFO,
28 HELP_FORMAT_WEB,
29 };
30
31 static int show_all = 0;
32 static enum help_format help_format = HELP_FORMAT_MAN;
33 static 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
43 static const char * const builtin_help_usage[] = {
44 "git help [--all] [--man|--web|--info] [command]",
45 NULL
46 };
47
48 static 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
59 static 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
71 static 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;
83 if (start_command(&ec_process)) {
84 fprintf(stderr, "Failed to start emacsclient.\n");
85 return -1;
86 }
87 strbuf_read(&buffer, ec_process.err, 20);
88 close(ec_process.err);
89
90 /*
91 * Don't bother checking return value, because "emacsclient --version"
92 * seems to always exits with code 1.
93 */
94 finish_command(&ec_process);
95
96 if (prefixcmp(buffer.buf, "emacsclient")) {
97 fprintf(stderr, "Failed to parse emacsclient version.\n");
98 strbuf_release(&buffer);
99 return -1;
100 }
101
102 strbuf_remove(&buffer, 0, strlen("emacsclient"));
103 version = atoi(buffer.buf);
104
105 if (version < 22) {
106 fprintf(stderr,
107 "emacsclient version '%d' too old (< 22).\n",
108 version);
109 strbuf_release(&buffer);
110 return -1;
111 }
112
113 strbuf_release(&buffer);
114 return 0;
115 }
116
117 static void exec_woman_emacs(const char *path, const char *page)
118 {
119 if (!check_emacsclient_version()) {
120 /* This works only with emacsclient version >= 22. */
121 struct strbuf man_page = STRBUF_INIT;
122
123 if (!path)
124 path = "emacsclient";
125 strbuf_addf(&man_page, "(woman \"%s\")", page);
126 execlp(path, "emacsclient", "-e", man_page.buf, NULL);
127 warning("failed to exec '%s': %s", path, strerror(errno));
128 }
129 }
130
131 static void exec_man_konqueror(const char *path, const char *page)
132 {
133 const char *display = getenv("DISPLAY");
134 if (display && *display) {
135 struct strbuf man_page = STRBUF_INIT;
136 const char *filename = "kfmclient";
137
138 /* It's simpler to launch konqueror using kfmclient. */
139 if (path) {
140 const char *file = strrchr(path, '/');
141 if (file && !strcmp(file + 1, "konqueror")) {
142 char *new = xstrdup(path);
143 char *dest = strrchr(new, '/');
144
145 /* strlen("konqueror") == strlen("kfmclient") */
146 strcpy(dest + 1, "kfmclient");
147 path = new;
148 }
149 if (file)
150 filename = file;
151 } else
152 path = "kfmclient";
153 strbuf_addf(&man_page, "man:%s(1)", page);
154 execlp(path, filename, "newTab", man_page.buf, NULL);
155 warning("failed to exec '%s': %s", path, strerror(errno));
156 }
157 }
158
159 static void exec_man_man(const char *path, const char *page)
160 {
161 if (!path)
162 path = "man";
163 execlp(path, "man", page, NULL);
164 warning("failed to exec '%s': %s", path, strerror(errno));
165 }
166
167 static void exec_man_cmd(const char *cmd, const char *page)
168 {
169 struct strbuf shell_cmd = STRBUF_INIT;
170 strbuf_addf(&shell_cmd, "%s %s", cmd, page);
171 execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
172 warning("failed to exec '%s': %s", cmd, strerror(errno));
173 }
174
175 static void add_man_viewer(const char *name)
176 {
177 struct man_viewer_list **p = &man_viewer_list;
178 size_t len = strlen(name);
179
180 while (*p)
181 p = &((*p)->next);
182 *p = xcalloc(1, (sizeof(**p) + len + 1));
183 strncpy((*p)->name, name, len);
184 }
185
186 static int supported_man_viewer(const char *name, size_t len)
187 {
188 return (!strncasecmp("man", name, len) ||
189 !strncasecmp("woman", name, len) ||
190 !strncasecmp("konqueror", name, len));
191 }
192
193 static void do_add_man_viewer_info(const char *name,
194 size_t len,
195 const char *value)
196 {
197 struct man_viewer_info_list *new = xcalloc(1, sizeof(*new) + len + 1);
198
199 strncpy(new->name, name, len);
200 new->info = xstrdup(value);
201 new->next = man_viewer_info_list;
202 man_viewer_info_list = new;
203 }
204
205 static int add_man_viewer_path(const char *name,
206 size_t len,
207 const char *value)
208 {
209 if (supported_man_viewer(name, len))
210 do_add_man_viewer_info(name, len, value);
211 else
212 warning("'%s': path for unsupported man viewer.\n"
213 "Please consider using 'man.<tool>.cmd' instead.",
214 name);
215
216 return 0;
217 }
218
219 static int add_man_viewer_cmd(const char *name,
220 size_t len,
221 const char *value)
222 {
223 if (supported_man_viewer(name, len))
224 warning("'%s': cmd for supported man viewer.\n"
225 "Please consider using 'man.<tool>.path' instead.",
226 name);
227 else
228 do_add_man_viewer_info(name, len, value);
229
230 return 0;
231 }
232
233 static int add_man_viewer_info(const char *var, const char *value)
234 {
235 const char *name = var + 4;
236 const char *subkey = strrchr(name, '.');
237
238 if (!subkey)
239 return 0;
240
241 if (!strcmp(subkey, ".path")) {
242 if (!value)
243 return config_error_nonbool(var);
244 return add_man_viewer_path(name, subkey - name, value);
245 }
246 if (!strcmp(subkey, ".cmd")) {
247 if (!value)
248 return config_error_nonbool(var);
249 return add_man_viewer_cmd(name, subkey - name, value);
250 }
251
252 return 0;
253 }
254
255 static int git_help_config(const char *var, const char *value, void *cb)
256 {
257 if (!strcmp(var, "help.format")) {
258 if (!value)
259 return config_error_nonbool(var);
260 help_format = parse_help_format(value);
261 return 0;
262 }
263 if (!strcmp(var, "man.viewer")) {
264 if (!value)
265 return config_error_nonbool(var);
266 add_man_viewer(value);
267 return 0;
268 }
269 if (!prefixcmp(var, "man."))
270 return add_man_viewer_info(var, value);
271
272 return git_default_config(var, value, cb);
273 }
274
275 static struct cmdnames main_cmds, other_cmds;
276
277 void list_common_cmds_help(void)
278 {
279 int i, longest = 0;
280
281 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
282 if (longest < strlen(common_cmds[i].name))
283 longest = strlen(common_cmds[i].name);
284 }
285
286 puts("The most commonly used git commands are:");
287 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
288 printf(" %s ", common_cmds[i].name);
289 mput_char(' ', longest - strlen(common_cmds[i].name));
290 puts(common_cmds[i].help);
291 }
292 }
293
294 static int is_git_command(const char *s)
295 {
296 return is_in_cmdlist(&main_cmds, s) ||
297 is_in_cmdlist(&other_cmds, s);
298 }
299
300 static const char *prepend(const char *prefix, const char *cmd)
301 {
302 size_t pre_len = strlen(prefix);
303 size_t cmd_len = strlen(cmd);
304 char *p = xmalloc(pre_len + cmd_len + 1);
305 memcpy(p, prefix, pre_len);
306 strcpy(p + pre_len, cmd);
307 return p;
308 }
309
310 static const char *cmd_to_page(const char *git_cmd)
311 {
312 if (!git_cmd)
313 return "git";
314 else if (!prefixcmp(git_cmd, "git"))
315 return git_cmd;
316 else if (is_git_command(git_cmd))
317 return prepend("git-", git_cmd);
318 else
319 return prepend("git", git_cmd);
320 }
321
322 static void setup_man_path(void)
323 {
324 struct strbuf new_path = STRBUF_INIT;
325 const char *old_path = getenv("MANPATH");
326
327 /* We should always put ':' after our path. If there is no
328 * old_path, the ':' at the end will let 'man' to try
329 * system-wide paths after ours to find the manual page. If
330 * there is old_path, we need ':' as delimiter. */
331 strbuf_addstr(&new_path, system_path(GIT_MAN_PATH));
332 strbuf_addch(&new_path, ':');
333 if (old_path)
334 strbuf_addstr(&new_path, old_path);
335
336 setenv("MANPATH", new_path.buf, 1);
337
338 strbuf_release(&new_path);
339 }
340
341 static void exec_viewer(const char *name, const char *page)
342 {
343 const char *info = get_man_viewer_info(name);
344
345 if (!strcasecmp(name, "man"))
346 exec_man_man(info, page);
347 else if (!strcasecmp(name, "woman"))
348 exec_woman_emacs(info, page);
349 else if (!strcasecmp(name, "konqueror"))
350 exec_man_konqueror(info, page);
351 else if (info)
352 exec_man_cmd(info, page);
353 else
354 warning("'%s': unknown man viewer.", name);
355 }
356
357 static void show_man_page(const char *git_cmd)
358 {
359 struct man_viewer_list *viewer;
360 const char *page = cmd_to_page(git_cmd);
361 const char *fallback = getenv("GIT_MAN_VIEWER");
362
363 setup_man_path();
364 for (viewer = man_viewer_list; viewer; viewer = viewer->next)
365 {
366 exec_viewer(viewer->name, page); /* will return when unable */
367 }
368 if (fallback)
369 exec_viewer(fallback, page);
370 exec_viewer("man", page);
371 die("no man viewer handled the request");
372 }
373
374 static void show_info_page(const char *git_cmd)
375 {
376 const char *page = cmd_to_page(git_cmd);
377 setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
378 execlp("info", "info", "gitman", page, NULL);
379 }
380
381 static void get_html_page_path(struct strbuf *page_path, const char *page)
382 {
383 struct stat st;
384 const char *html_path = system_path(GIT_HTML_PATH);
385
386 /* Check that we have a git documentation directory. */
387 if (stat(mkpath("%s/git.html", html_path), &st)
388 || !S_ISREG(st.st_mode))
389 die("'%s': not a documentation directory.", html_path);
390
391 strbuf_init(page_path, 0);
392 strbuf_addf(page_path, "%s/%s.html", html_path, page);
393 }
394
395 /*
396 * If open_html is not defined in a platform-specific way (see for
397 * example compat/mingw.h), we use the script web--browse to display
398 * HTML.
399 */
400 #ifndef open_html
401 void open_html(const char *path)
402 {
403 execl_git_cmd("web--browse", "-c", "help.browser", path, NULL);
404 }
405 #endif
406
407 static void show_html_page(const char *git_cmd)
408 {
409 const char *page = cmd_to_page(git_cmd);
410 struct strbuf page_path; /* it leaks but we exec bellow */
411
412 get_html_page_path(&page_path, page);
413
414 open_html(page_path.buf);
415 }
416
417 int cmd_help(int argc, const char **argv, const char *prefix)
418 {
419 int nongit;
420 const char *alias;
421 load_command_list("git-", &main_cmds, &other_cmds);
422
423 setup_git_directory_gently(&nongit);
424 git_config(git_help_config, NULL);
425
426 argc = parse_options(argc, argv, builtin_help_options,
427 builtin_help_usage, 0);
428
429 if (show_all) {
430 printf("usage: %s\n\n", git_usage_string);
431 list_commands("git commands", &main_cmds, &other_cmds);
432 printf("%s\n", git_more_info_string);
433 return 0;
434 }
435
436 if (!argv[0]) {
437 printf("usage: %s\n\n", git_usage_string);
438 list_common_cmds_help();
439 printf("\n%s\n", git_more_info_string);
440 return 0;
441 }
442
443 alias = alias_lookup(argv[0]);
444 if (alias && !is_git_command(argv[0])) {
445 printf("`git %s' is aliased to `%s'\n", argv[0], alias);
446 return 0;
447 }
448
449 switch (help_format) {
450 case HELP_FORMAT_MAN:
451 show_man_page(argv[0]);
452 break;
453 case HELP_FORMAT_INFO:
454 show_info_page(argv[0]);
455 break;
456 case HELP_FORMAT_WEB:
457 show_html_page(argv[0]);
458 break;
459 }
460
461 return 0;
462 }