Merge branch 'os/no-verify-skips-commit-msg-too' into maint
[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 }