2ff3b5a7745dbb7937896fb2303c9299387929de
[git/git.git] / help.c
1 #include "cache.h"
2 #include "builtin.h"
3 #include "exec_cmd.h"
4 #include "levenshtein.h"
5 #include "help.h"
6 #include "common-cmds.h"
7 #include "string-list.h"
8 #include "column.h"
9 #include "version.h"
10 #include "refs.h"
11
12 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
13 {
14 struct cmdname *ent;
15 FLEX_ALLOC_MEM(ent, name, name, len);
16 ent->len = len;
17
18 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
19 cmds->names[cmds->cnt++] = ent;
20 }
21
22 static void clean_cmdnames(struct cmdnames *cmds)
23 {
24 int i;
25 for (i = 0; i < cmds->cnt; ++i)
26 free(cmds->names[i]);
27 free(cmds->names);
28 cmds->cnt = 0;
29 cmds->alloc = 0;
30 }
31
32 static int cmdname_compare(const void *a_, const void *b_)
33 {
34 struct cmdname *a = *(struct cmdname **)a_;
35 struct cmdname *b = *(struct cmdname **)b_;
36 return strcmp(a->name, b->name);
37 }
38
39 static void uniq(struct cmdnames *cmds)
40 {
41 int i, j;
42
43 if (!cmds->cnt)
44 return;
45
46 for (i = j = 1; i < cmds->cnt; i++) {
47 if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
48 free(cmds->names[i]);
49 else
50 cmds->names[j++] = cmds->names[i];
51 }
52
53 cmds->cnt = j;
54 }
55
56 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
57 {
58 int ci, cj, ei;
59 int cmp;
60
61 ci = cj = ei = 0;
62 while (ci < cmds->cnt && ei < excludes->cnt) {
63 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
64 if (cmp < 0)
65 cmds->names[cj++] = cmds->names[ci++];
66 else if (cmp == 0) {
67 ei++;
68 free(cmds->names[ci++]);
69 } else if (cmp > 0)
70 ei++;
71 }
72
73 while (ci < cmds->cnt)
74 cmds->names[cj++] = cmds->names[ci++];
75
76 cmds->cnt = cj;
77 }
78
79 static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
80 {
81 struct string_list list = STRING_LIST_INIT_NODUP;
82 struct column_options copts;
83 int i;
84
85 for (i = 0; i < cmds->cnt; i++)
86 string_list_append(&list, cmds->names[i]->name);
87 /*
88 * always enable column display, we only consult column.*
89 * about layout strategy and stuff
90 */
91 colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
92 memset(&copts, 0, sizeof(copts));
93 copts.indent = " ";
94 copts.padding = 2;
95 print_columns(&list, colopts, &copts);
96 string_list_clear(&list, 0);
97 }
98
99 static int is_executable(const char *name)
100 {
101 struct stat st;
102
103 if (stat(name, &st) || /* stat, not lstat */
104 !S_ISREG(st.st_mode))
105 return 0;
106
107 #if defined(GIT_WINDOWS_NATIVE)
108 { /* cannot trust the executable bit, peek into the file instead */
109 char buf[3] = { 0 };
110 int n;
111 int fd = open(name, O_RDONLY);
112 st.st_mode &= ~S_IXUSR;
113 if (fd >= 0) {
114 n = read(fd, buf, 2);
115 if (n == 2)
116 /* DOS executables start with "MZ" */
117 if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
118 st.st_mode |= S_IXUSR;
119 close(fd);
120 }
121 }
122 #endif
123 return st.st_mode & S_IXUSR;
124 }
125
126 static void list_commands_in_dir(struct cmdnames *cmds,
127 const char *path,
128 const char *prefix)
129 {
130 DIR *dir = opendir(path);
131 struct dirent *de;
132 struct strbuf buf = STRBUF_INIT;
133 int len;
134
135 if (!dir)
136 return;
137 if (!prefix)
138 prefix = "git-";
139
140 strbuf_addf(&buf, "%s/", path);
141 len = buf.len;
142
143 while ((de = readdir(dir)) != NULL) {
144 const char *ent;
145 size_t entlen;
146
147 if (!skip_prefix(de->d_name, prefix, &ent))
148 continue;
149
150 strbuf_setlen(&buf, len);
151 strbuf_addstr(&buf, de->d_name);
152 if (!is_executable(buf.buf))
153 continue;
154
155 entlen = strlen(ent);
156 strip_suffix(ent, ".exe", &entlen);
157
158 add_cmdname(cmds, ent, entlen);
159 }
160 closedir(dir);
161 strbuf_release(&buf);
162 }
163
164 void load_command_list(const char *prefix,
165 struct cmdnames *main_cmds,
166 struct cmdnames *other_cmds)
167 {
168 const char *env_path = getenv("PATH");
169 const char *exec_path = git_exec_path();
170
171 if (exec_path) {
172 list_commands_in_dir(main_cmds, exec_path, prefix);
173 qsort(main_cmds->names, main_cmds->cnt,
174 sizeof(*main_cmds->names), cmdname_compare);
175 uniq(main_cmds);
176 }
177
178 if (env_path) {
179 char *paths, *path, *colon;
180 path = paths = xstrdup(env_path);
181 while (1) {
182 if ((colon = strchr(path, PATH_SEP)))
183 *colon = 0;
184 if (!exec_path || strcmp(path, exec_path))
185 list_commands_in_dir(other_cmds, path, prefix);
186
187 if (!colon)
188 break;
189 path = colon + 1;
190 }
191 free(paths);
192
193 qsort(other_cmds->names, other_cmds->cnt,
194 sizeof(*other_cmds->names), cmdname_compare);
195 uniq(other_cmds);
196 }
197 exclude_cmds(other_cmds, main_cmds);
198 }
199
200 void list_commands(unsigned int colopts,
201 struct cmdnames *main_cmds, struct cmdnames *other_cmds)
202 {
203 if (main_cmds->cnt) {
204 const char *exec_path = git_exec_path();
205 printf_ln(_("available git commands in '%s'"), exec_path);
206 putchar('\n');
207 pretty_print_cmdnames(main_cmds, colopts);
208 putchar('\n');
209 }
210
211 if (other_cmds->cnt) {
212 printf_ln(_("git commands available from elsewhere on your $PATH"));
213 putchar('\n');
214 pretty_print_cmdnames(other_cmds, colopts);
215 putchar('\n');
216 }
217 }
218
219 static int cmd_group_cmp(const void *elem1, const void *elem2)
220 {
221 const struct cmdname_help *e1 = elem1;
222 const struct cmdname_help *e2 = elem2;
223
224 if (e1->group < e2->group)
225 return -1;
226 if (e1->group > e2->group)
227 return 1;
228 return strcmp(e1->name, e2->name);
229 }
230
231 void list_common_cmds_help(void)
232 {
233 int i, longest = 0;
234 int current_grp = -1;
235
236 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
237 if (longest < strlen(common_cmds[i].name))
238 longest = strlen(common_cmds[i].name);
239 }
240
241 qsort(common_cmds, ARRAY_SIZE(common_cmds),
242 sizeof(common_cmds[0]), cmd_group_cmp);
243
244 puts(_("These are common Git commands used in various situations:"));
245
246 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
247 if (common_cmds[i].group != current_grp) {
248 printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
249 current_grp = common_cmds[i].group;
250 }
251
252 printf(" %s ", common_cmds[i].name);
253 mput_char(' ', longest - strlen(common_cmds[i].name));
254 puts(_(common_cmds[i].help));
255 }
256 }
257
258 int is_in_cmdlist(struct cmdnames *c, const char *s)
259 {
260 int i;
261 for (i = 0; i < c->cnt; i++)
262 if (!strcmp(s, c->names[i]->name))
263 return 1;
264 return 0;
265 }
266
267 static int autocorrect;
268 static struct cmdnames aliases;
269
270 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
271 {
272 const char *p;
273
274 if (!strcmp(var, "help.autocorrect"))
275 autocorrect = git_config_int(var,value);
276 /* Also use aliases for command lookup */
277 if (skip_prefix(var, "alias.", &p))
278 add_cmdname(&aliases, p, strlen(p));
279
280 return git_default_config(var, value, cb);
281 }
282
283 static int levenshtein_compare(const void *p1, const void *p2)
284 {
285 const struct cmdname *const *c1 = p1, *const *c2 = p2;
286 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
287 int l1 = (*c1)->len;
288 int l2 = (*c2)->len;
289 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
290 }
291
292 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
293 {
294 int i;
295 ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
296
297 for (i = 0; i < old->cnt; i++)
298 cmds->names[cmds->cnt++] = old->names[i];
299 free(old->names);
300 old->cnt = 0;
301 old->names = NULL;
302 }
303
304 /* An empirically derived magic number */
305 #define SIMILARITY_FLOOR 7
306 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
307
308 static const char bad_interpreter_advice[] =
309 N_("'%s' appears to be a git command, but we were not\n"
310 "able to execute it. Maybe git-%s is broken?");
311
312 const char *help_unknown_cmd(const char *cmd)
313 {
314 int i, n, best_similarity = 0;
315 struct cmdnames main_cmds, other_cmds;
316
317 memset(&main_cmds, 0, sizeof(main_cmds));
318 memset(&other_cmds, 0, sizeof(other_cmds));
319 memset(&aliases, 0, sizeof(aliases));
320
321 git_config(git_unknown_cmd_config, NULL);
322
323 load_command_list("git-", &main_cmds, &other_cmds);
324
325 add_cmd_list(&main_cmds, &aliases);
326 add_cmd_list(&main_cmds, &other_cmds);
327 qsort(main_cmds.names, main_cmds.cnt,
328 sizeof(*main_cmds.names), cmdname_compare);
329 uniq(&main_cmds);
330
331 /* This abuses cmdname->len for levenshtein distance */
332 for (i = 0, n = 0; i < main_cmds.cnt; i++) {
333 int cmp = 0; /* avoid compiler stupidity */
334 const char *candidate = main_cmds.names[i]->name;
335
336 /*
337 * An exact match means we have the command, but
338 * for some reason exec'ing it gave us ENOENT; probably
339 * it's a bad interpreter in the #! line.
340 */
341 if (!strcmp(candidate, cmd))
342 die(_(bad_interpreter_advice), cmd, cmd);
343
344 /* Does the candidate appear in common_cmds list? */
345 while (n < ARRAY_SIZE(common_cmds) &&
346 (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
347 n++;
348 if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
349 /* Yes, this is one of the common commands */
350 n++; /* use the entry from common_cmds[] */
351 if (starts_with(candidate, cmd)) {
352 /* Give prefix match a very good score */
353 main_cmds.names[i]->len = 0;
354 continue;
355 }
356 }
357
358 main_cmds.names[i]->len =
359 levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
360 }
361
362 qsort(main_cmds.names, main_cmds.cnt,
363 sizeof(*main_cmds.names), levenshtein_compare);
364
365 if (!main_cmds.cnt)
366 die(_("Uh oh. Your system reports no Git commands at all."));
367
368 /* skip and count prefix matches */
369 for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
370 ; /* still counting */
371
372 if (main_cmds.cnt <= n) {
373 /* prefix matches with everything? that is too ambiguous */
374 best_similarity = SIMILARITY_FLOOR + 1;
375 } else {
376 /* count all the most similar ones */
377 for (best_similarity = main_cmds.names[n++]->len;
378 (n < main_cmds.cnt &&
379 best_similarity == main_cmds.names[n]->len);
380 n++)
381 ; /* still counting */
382 }
383 if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
384 const char *assumed = main_cmds.names[0]->name;
385 main_cmds.names[0] = NULL;
386 clean_cmdnames(&main_cmds);
387 fprintf_ln(stderr,
388 _("WARNING: You called a Git command named '%s', "
389 "which does not exist.\n"
390 "Continuing under the assumption that you meant '%s'"),
391 cmd, assumed);
392 if (autocorrect > 0) {
393 fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
394 (float)autocorrect/10.0);
395 sleep_millisec(autocorrect * 100);
396 }
397 return assumed;
398 }
399
400 fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
401
402 if (SIMILAR_ENOUGH(best_similarity)) {
403 fprintf_ln(stderr,
404 Q_("\nDid you mean this?",
405 "\nDid you mean one of these?",
406 n));
407
408 for (i = 0; i < n; i++)
409 fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
410 }
411
412 exit(1);
413 }
414
415 int cmd_version(int argc, const char **argv, const char *prefix)
416 {
417 /*
418 * The format of this string should be kept stable for compatibility
419 * with external projects that rely on the output of "git version".
420 */
421 printf("git version %s\n", git_version_string);
422 while (*++argv) {
423 if (!strcmp(*argv, "--build-options")) {
424 printf("sizeof-long: %d\n", (int)sizeof(long));
425 /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
426 }
427 }
428 return 0;
429 }
430
431 struct similar_ref_cb {
432 const char *base_ref;
433 struct string_list *similar_refs;
434 };
435
436 static int append_similar_ref(const char *refname, const struct object_id *oid,
437 int flags, void *cb_data)
438 {
439 struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
440 char *branch = strrchr(refname, '/') + 1;
441 const char *remote;
442
443 /* A remote branch of the same name is deemed similar */
444 if (skip_prefix(refname, "refs/remotes/", &remote) &&
445 !strcmp(branch, cb->base_ref))
446 string_list_append(cb->similar_refs, remote);
447 return 0;
448 }
449
450 static struct string_list guess_refs(const char *ref)
451 {
452 struct similar_ref_cb ref_cb;
453 struct string_list similar_refs = STRING_LIST_INIT_NODUP;
454
455 ref_cb.base_ref = ref;
456 ref_cb.similar_refs = &similar_refs;
457 for_each_ref(append_similar_ref, &ref_cb);
458 return similar_refs;
459 }
460
461 void help_unknown_ref(const char *ref, const char *cmd, const char *error)
462 {
463 int i;
464 struct string_list suggested_refs = guess_refs(ref);
465
466 fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
467
468 if (suggested_refs.nr > 0) {
469 fprintf_ln(stderr,
470 Q_("\nDid you mean this?",
471 "\nDid you mean one of these?",
472 suggested_refs.nr));
473 for (i = 0; i < suggested_refs.nr; i++)
474 fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
475 }
476
477 string_list_clear(&suggested_refs, 0);
478 exit(1);
479 }