Merge branch 'jn/gitweb-grep'
[git/git.git] / help.c
1 /*
2 * builtin-help.c
3 *
4 * Builtin help-related commands (help, usage, version)
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
12 enum help_format {
13 HELP_FORMAT_MAN,
14 HELP_FORMAT_INFO,
15 HELP_FORMAT_WEB,
16 };
17
18 static int show_all = 0;
19 static enum help_format help_format = HELP_FORMAT_MAN;
20 static struct option builtin_help_options[] = {
21 OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
22 OPT_SET_INT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
23 OPT_SET_INT('w', "web", &help_format, "show manual in web browser",
24 HELP_FORMAT_WEB),
25 OPT_SET_INT('i', "info", &help_format, "show info page",
26 HELP_FORMAT_INFO),
27 };
28
29 static const char * const builtin_help_usage[] = {
30 "git-help [--all] [--man|--web|--info] [command]",
31 NULL
32 };
33
34 static enum help_format parse_help_format(const char *format)
35 {
36 if (!strcmp(format, "man"))
37 return HELP_FORMAT_MAN;
38 if (!strcmp(format, "info"))
39 return HELP_FORMAT_INFO;
40 if (!strcmp(format, "web") || !strcmp(format, "html"))
41 return HELP_FORMAT_WEB;
42 die("unrecognized help format '%s'", format);
43 }
44
45 static int git_help_config(const char *var, const char *value)
46 {
47 if (!strcmp(var, "help.format")) {
48 if (!value)
49 return config_error_nonbool(var);
50 help_format = parse_help_format(value);
51 return 0;
52 }
53 return git_default_config(var, value);
54 }
55
56 /* most GUI terminals set COLUMNS (although some don't export it) */
57 static int term_columns(void)
58 {
59 char *col_string = getenv("COLUMNS");
60 int n_cols;
61
62 if (col_string && (n_cols = atoi(col_string)) > 0)
63 return n_cols;
64
65 #ifdef TIOCGWINSZ
66 {
67 struct winsize ws;
68 if (!ioctl(1, TIOCGWINSZ, &ws)) {
69 if (ws.ws_col)
70 return ws.ws_col;
71 }
72 }
73 #endif
74
75 return 80;
76 }
77
78 static inline void mput_char(char c, unsigned int num)
79 {
80 while(num--)
81 putchar(c);
82 }
83
84 static struct cmdnames {
85 int alloc;
86 int cnt;
87 struct cmdname {
88 size_t len;
89 char name[1];
90 } **names;
91 } main_cmds, other_cmds;
92
93 static void add_cmdname(struct cmdnames *cmds, const char *name, int len)
94 {
95 struct cmdname *ent = xmalloc(sizeof(*ent) + len);
96
97 ent->len = len;
98 memcpy(ent->name, name, len);
99 ent->name[len] = 0;
100
101 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
102 cmds->names[cmds->cnt++] = ent;
103 }
104
105 static int cmdname_compare(const void *a_, const void *b_)
106 {
107 struct cmdname *a = *(struct cmdname **)a_;
108 struct cmdname *b = *(struct cmdname **)b_;
109 return strcmp(a->name, b->name);
110 }
111
112 static void uniq(struct cmdnames *cmds)
113 {
114 int i, j;
115
116 if (!cmds->cnt)
117 return;
118
119 for (i = j = 1; i < cmds->cnt; i++)
120 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
121 cmds->names[j++] = cmds->names[i];
122
123 cmds->cnt = j;
124 }
125
126 static void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
127 {
128 int ci, cj, ei;
129 int cmp;
130
131 ci = cj = ei = 0;
132 while (ci < cmds->cnt && ei < excludes->cnt) {
133 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
134 if (cmp < 0)
135 cmds->names[cj++] = cmds->names[ci++];
136 else if (cmp == 0)
137 ci++, ei++;
138 else if (cmp > 0)
139 ei++;
140 }
141
142 while (ci < cmds->cnt)
143 cmds->names[cj++] = cmds->names[ci++];
144
145 cmds->cnt = cj;
146 }
147
148 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
149 {
150 int cols = 1, rows;
151 int space = longest + 1; /* min 1 SP between words */
152 int max_cols = term_columns() - 1; /* don't print *on* the edge */
153 int i, j;
154
155 if (space < max_cols)
156 cols = max_cols / space;
157 rows = (cmds->cnt + cols - 1) / cols;
158
159 for (i = 0; i < rows; i++) {
160 printf(" ");
161
162 for (j = 0; j < cols; j++) {
163 int n = j * rows + i;
164 int size = space;
165 if (n >= cmds->cnt)
166 break;
167 if (j == cols-1 || n + rows >= cmds->cnt)
168 size = 1;
169 printf("%-*s", size, cmds->names[n]->name);
170 }
171 putchar('\n');
172 }
173 }
174
175 static unsigned int list_commands_in_dir(struct cmdnames *cmds,
176 const char *path)
177 {
178 unsigned int longest = 0;
179 const char *prefix = "git-";
180 int prefix_len = strlen(prefix);
181 DIR *dir = opendir(path);
182 struct dirent *de;
183
184 if (!dir || chdir(path))
185 return 0;
186
187 while ((de = readdir(dir)) != NULL) {
188 struct stat st;
189 int entlen;
190
191 if (prefixcmp(de->d_name, prefix))
192 continue;
193
194 if (stat(de->d_name, &st) || /* stat, not lstat */
195 !S_ISREG(st.st_mode) ||
196 !(st.st_mode & S_IXUSR))
197 continue;
198
199 entlen = strlen(de->d_name) - prefix_len;
200 if (has_extension(de->d_name, ".exe"))
201 entlen -= 4;
202
203 if (longest < entlen)
204 longest = entlen;
205
206 add_cmdname(cmds, de->d_name + prefix_len, entlen);
207 }
208 closedir(dir);
209
210 return longest;
211 }
212
213 static unsigned int load_command_list(void)
214 {
215 unsigned int longest = 0;
216 unsigned int len;
217 const char *env_path = getenv("PATH");
218 char *paths, *path, *colon;
219 const char *exec_path = git_exec_path();
220
221 if (exec_path)
222 longest = list_commands_in_dir(&main_cmds, exec_path);
223
224 if (!env_path) {
225 fprintf(stderr, "PATH not set\n");
226 exit(1);
227 }
228
229 path = paths = xstrdup(env_path);
230 while (1) {
231 if ((colon = strchr(path, ':')))
232 *colon = 0;
233
234 len = list_commands_in_dir(&other_cmds, path);
235 if (len > longest)
236 longest = len;
237
238 if (!colon)
239 break;
240 path = colon + 1;
241 }
242 free(paths);
243
244 qsort(main_cmds.names, main_cmds.cnt,
245 sizeof(*main_cmds.names), cmdname_compare);
246 uniq(&main_cmds);
247
248 qsort(other_cmds.names, other_cmds.cnt,
249 sizeof(*other_cmds.names), cmdname_compare);
250 uniq(&other_cmds);
251 exclude_cmds(&other_cmds, &main_cmds);
252
253 return longest;
254 }
255
256 static void list_commands(void)
257 {
258 unsigned int longest = load_command_list();
259 const char *exec_path = git_exec_path();
260
261 if (main_cmds.cnt) {
262 printf("available git commands in '%s'\n", exec_path);
263 printf("----------------------------");
264 mput_char('-', strlen(exec_path));
265 putchar('\n');
266 pretty_print_string_list(&main_cmds, longest);
267 putchar('\n');
268 }
269
270 if (other_cmds.cnt) {
271 printf("git commands available from elsewhere on your $PATH\n");
272 printf("---------------------------------------------------\n");
273 pretty_print_string_list(&other_cmds, longest);
274 putchar('\n');
275 }
276 }
277
278 void list_common_cmds_help(void)
279 {
280 int i, longest = 0;
281
282 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
283 if (longest < strlen(common_cmds[i].name))
284 longest = strlen(common_cmds[i].name);
285 }
286
287 puts("The most commonly used git commands are:");
288 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
289 printf(" %s ", common_cmds[i].name);
290 mput_char(' ', longest - strlen(common_cmds[i].name));
291 puts(common_cmds[i].help);
292 }
293 }
294
295 static int is_in_cmdlist(struct cmdnames *c, const char *s)
296 {
297 int i;
298 for (i = 0; i < c->cnt; i++)
299 if (!strcmp(s, c->names[i]->name))
300 return 1;
301 return 0;
302 }
303
304 static int is_git_command(const char *s)
305 {
306 load_command_list();
307 return is_in_cmdlist(&main_cmds, s) ||
308 is_in_cmdlist(&other_cmds, s);
309 }
310
311 static const char *cmd_to_page(const char *git_cmd)
312 {
313 if (!git_cmd)
314 return "git";
315 else if (!prefixcmp(git_cmd, "git"))
316 return git_cmd;
317 else {
318 int page_len = strlen(git_cmd) + 4;
319 char *p = xmalloc(page_len + 1);
320 strcpy(p, "git-");
321 strcpy(p + 4, git_cmd);
322 p[page_len] = 0;
323 return p;
324 }
325 }
326
327 static void setup_man_path(void)
328 {
329 struct strbuf new_path;
330 const char *old_path = getenv("MANPATH");
331
332 strbuf_init(&new_path, 0);
333
334 /* We should always put ':' after our path. If there is no
335 * old_path, the ':' at the end will let 'man' to try
336 * system-wide paths after ours to find the manual page. If
337 * there is old_path, we need ':' as delimiter. */
338 strbuf_addstr(&new_path, GIT_MAN_PATH);
339 strbuf_addch(&new_path, ':');
340 if (old_path)
341 strbuf_addstr(&new_path, old_path);
342
343 setenv("MANPATH", new_path.buf, 1);
344
345 strbuf_release(&new_path);
346 }
347
348 static void show_man_page(const char *git_cmd)
349 {
350 const char *page = cmd_to_page(git_cmd);
351 setup_man_path();
352 execlp("man", "man", page, NULL);
353 }
354
355 static void show_info_page(const char *git_cmd)
356 {
357 const char *page = cmd_to_page(git_cmd);
358 setenv("INFOPATH", GIT_INFO_PATH, 1);
359 execlp("info", "info", "gitman", page, NULL);
360 }
361
362 static void get_html_page_path(struct strbuf *page_path, const char *page)
363 {
364 struct stat st;
365
366 /* Check that we have a git documentation directory. */
367 if (stat(GIT_HTML_PATH "/git.html", &st) || !S_ISREG(st.st_mode))
368 die("'%s': not a documentation directory.", GIT_HTML_PATH);
369
370 strbuf_init(page_path, 0);
371 strbuf_addf(page_path, GIT_HTML_PATH "/%s.html", page);
372 }
373
374 static void show_html_page(const char *git_cmd)
375 {
376 const char *page = cmd_to_page(git_cmd);
377 struct strbuf page_path; /* it leaks but we exec bellow */
378
379 get_html_page_path(&page_path, page);
380
381 execl_git_cmd("web--browse", "-c", "help.browser", page_path.buf, NULL);
382 }
383
384 void help_unknown_cmd(const char *cmd)
385 {
386 fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
387 exit(1);
388 }
389
390 int cmd_version(int argc, const char **argv, const char *prefix)
391 {
392 printf("git version %s\n", git_version_string);
393 return 0;
394 }
395
396 int cmd_help(int argc, const char **argv, const char *prefix)
397 {
398 int nongit;
399 const char *alias;
400
401 setup_git_directory_gently(&nongit);
402 git_config(git_help_config);
403
404 argc = parse_options(argc, argv, builtin_help_options,
405 builtin_help_usage, 0);
406
407 if (show_all) {
408 printf("usage: %s\n\n", git_usage_string);
409 list_commands();
410 return 0;
411 }
412
413 if (!argv[0]) {
414 printf("usage: %s\n\n", git_usage_string);
415 list_common_cmds_help();
416 return 0;
417 }
418
419 alias = alias_lookup(argv[0]);
420 if (alias && !is_git_command(argv[0])) {
421 printf("`git %s' is aliased to `%s'\n", argv[0], alias);
422 return 0;
423 }
424
425 switch (help_format) {
426 case HELP_FORMAT_MAN:
427 show_man_page(argv[0]);
428 break;
429 case HELP_FORMAT_INFO:
430 show_info_page(argv[0]);
431 break;
432 case HELP_FORMAT_WEB:
433 show_html_page(argv[0]);
434 break;
435 }
436
437 return 0;
438 }