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gitweb: Fix unintended "--no-merges" for regular Atom feed
[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"
8 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
9 {
10         struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
12         ent->len = len;
13         memcpy(ent->name, name, len);
14         ent->name[len] = 0;
16         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
17         cmds->names[cmds->cnt++] = ent;
18 }
20 static void clean_cmdnames(struct cmdnames *cmds)
21 {
22         int i;
23         for (i = 0; i < cmds->cnt; ++i)
24                 free(cmds->names[i]);
25         free(cmds->names);
26         cmds->cnt = 0;
27         cmds->alloc = 0;
28 }
30 static int cmdname_compare(const void *a_, const void *b_)
31 {
32         struct cmdname *a = *(struct cmdname **)a_;
33         struct cmdname *b = *(struct cmdname **)b_;
34         return strcmp(a->name, b->name);
35 }
37 static void uniq(struct cmdnames *cmds)
38 {
39         int i, j;
41         if (!cmds->cnt)
42                 return;
44         for (i = j = 1; i < cmds->cnt; i++)
45                 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
46                         cmds->names[j++] = cmds->names[i];
48         cmds->cnt = j;
49 }
51 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
52 {
53         int ci, cj, ei;
54         int cmp;
56         ci = cj = ei = 0;
57         while (ci < cmds->cnt && ei < excludes->cnt) {
58                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
59                 if (cmp < 0)
60                         cmds->names[cj++] = cmds->names[ci++];
61                 else if (cmp == 0)
62                         ci++, ei++;
63                 else if (cmp > 0)
64                         ei++;
65         }
67         while (ci < cmds->cnt)
68                 cmds->names[cj++] = cmds->names[ci++];
70         cmds->cnt = cj;
71 }
73 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
74 {
75         int cols = 1, rows;
76         int space = longest + 1; /* min 1 SP between words */
77         int max_cols = term_columns() - 1; /* don't print *on* the edge */
78         int i, j;
80         if (space < max_cols)
81                 cols = max_cols / space;
82         rows = DIV_ROUND_UP(cmds->cnt, cols);
84         for (i = 0; i < rows; i++) {
85                 printf("  ");
87                 for (j = 0; j < cols; j++) {
88                         int n = j * rows + i;
89                         int size = space;
90                         if (n >= cmds->cnt)
91                                 break;
92                         if (j == cols-1 || n + rows >= cmds->cnt)
93                                 size = 1;
94                         printf("%-*s", size, cmds->names[n]->name);
95                 }
96                 putchar('\n');
97         }
98 }
100 static int is_executable(const char *name)
102         struct stat st;
104         if (stat(name, &st) || /* stat, not lstat */
105             !S_ISREG(st.st_mode))
106                 return 0;
108 #if defined(WIN32) || defined(__CYGWIN__)
109 #if defined(__CYGWIN__)
110 if ((st.st_mode & S_IXUSR) == 0)
111 #endif
112 {       /* cannot trust the executable bit, peek into the file instead */
113         char buf[3] = { 0 };
114         int n;
115         int fd = open(name, O_RDONLY);
116         st.st_mode &= ~S_IXUSR;
117         if (fd >= 0) {
118                 n = read(fd, buf, 2);
119                 if (n == 2)
120                         /* DOS executables start with "MZ" */
121                         if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
122                                 st.st_mode |= S_IXUSR;
123                 close(fd);
124         }
126 #endif
127         return st.st_mode & S_IXUSR;
130 static void list_commands_in_dir(struct cmdnames *cmds,
131                                          const char *path,
132                                          const char *prefix)
134         int prefix_len;
135         DIR *dir = opendir(path);
136         struct dirent *de;
137         struct strbuf buf = STRBUF_INIT;
138         int len;
140         if (!dir)
141                 return;
142         if (!prefix)
143                 prefix = "git-";
144         prefix_len = strlen(prefix);
146         strbuf_addf(&buf, "%s/", path);
147         len = buf.len;
149         while ((de = readdir(dir)) != NULL) {
150                 int entlen;
152                 if (prefixcmp(de->d_name, prefix))
153                         continue;
155                 strbuf_setlen(&buf, len);
156                 strbuf_addstr(&buf, de->d_name);
157                 if (!is_executable(buf.buf))
158                         continue;
160                 entlen = strlen(de->d_name) - prefix_len;
161                 if (has_extension(de->d_name, ".exe"))
162                         entlen -= 4;
164                 add_cmdname(cmds, de->d_name + prefix_len, entlen);
165         }
166         closedir(dir);
167         strbuf_release(&buf);
170 void load_command_list(const char *prefix,
171                 struct cmdnames *main_cmds,
172                 struct cmdnames *other_cmds)
174         const char *env_path = getenv("PATH");
175         const char *exec_path = git_exec_path();
177         if (exec_path) {
178                 list_commands_in_dir(main_cmds, exec_path, prefix);
179                 qsort(main_cmds->names, main_cmds->cnt,
180                       sizeof(*main_cmds->names), cmdname_compare);
181                 uniq(main_cmds);
182         }
184         if (env_path) {
185                 char *paths, *path, *colon;
186                 path = paths = xstrdup(env_path);
187                 while (1) {
188                         if ((colon = strchr(path, PATH_SEP)))
189                                 *colon = 0;
190                         if (!exec_path || strcmp(path, exec_path))
191                                 list_commands_in_dir(other_cmds, path, prefix);
193                         if (!colon)
194                                 break;
195                         path = colon + 1;
196                 }
197                 free(paths);
199                 qsort(other_cmds->names, other_cmds->cnt,
200                       sizeof(*other_cmds->names), cmdname_compare);
201                 uniq(other_cmds);
202         }
203         exclude_cmds(other_cmds, main_cmds);
206 void list_commands(const char *title, struct cmdnames *main_cmds,
207                    struct cmdnames *other_cmds)
209         int i, longest = 0;
211         for (i = 0; i < main_cmds->cnt; i++)
212                 if (longest < main_cmds->names[i]->len)
213                         longest = main_cmds->names[i]->len;
214         for (i = 0; i < other_cmds->cnt; i++)
215                 if (longest < other_cmds->names[i]->len)
216                         longest = other_cmds->names[i]->len;
218         if (main_cmds->cnt) {
219                 const char *exec_path = git_exec_path();
220                 printf("available %s in '%s'\n", title, exec_path);
221                 printf("----------------");
222                 mput_char('-', strlen(title) + strlen(exec_path));
223                 putchar('\n');
224                 pretty_print_string_list(main_cmds, longest);
225                 putchar('\n');
226         }
228         if (other_cmds->cnt) {
229                 printf("%s available from elsewhere on your $PATH\n", title);
230                 printf("---------------------------------------");
231                 mput_char('-', strlen(title));
232                 putchar('\n');
233                 pretty_print_string_list(other_cmds, longest);
234                 putchar('\n');
235         }
238 int is_in_cmdlist(struct cmdnames *c, const char *s)
240         int i;
241         for (i = 0; i < c->cnt; i++)
242                 if (!strcmp(s, c->names[i]->name))
243                         return 1;
244         return 0;
247 static int autocorrect;
248 static struct cmdnames aliases;
250 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
252         if (!strcmp(var, "help.autocorrect"))
253                 autocorrect = git_config_int(var,value);
254         /* Also use aliases for command lookup */
255         if (!prefixcmp(var, "alias."))
256                 add_cmdname(&aliases, var + 6, strlen(var + 6));
258         return git_default_config(var, value, cb);
261 static int levenshtein_compare(const void *p1, const void *p2)
263         const struct cmdname *const *c1 = p1, *const *c2 = p2;
264         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
265         int l1 = (*c1)->len;
266         int l2 = (*c2)->len;
267         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
270 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
272         int i;
273         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
275         for (i = 0; i < old->cnt; i++)
276                 cmds->names[cmds->cnt++] = old->names[i];
277         free(old->names);
278         old->cnt = 0;
279         old->names = NULL;
282 /* An empirically derived magic number */
283 #define SIMILARITY_FLOOR 7
284 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
286 static const char bad_interpreter_advice[] =
287         N_("'%s' appears to be a git command, but we were not\n"
288         "able to execute it. Maybe git-%s is broken?");
290 const char *help_unknown_cmd(const char *cmd)
292         int i, n, best_similarity = 0;
293         struct cmdnames main_cmds, other_cmds;
295         memset(&main_cmds, 0, sizeof(main_cmds));
296         memset(&other_cmds, 0, sizeof(other_cmds));
297         memset(&aliases, 0, sizeof(aliases));
299         git_config(git_unknown_cmd_config, NULL);
301         load_command_list("git-", &main_cmds, &other_cmds);
303         add_cmd_list(&main_cmds, &aliases);
304         add_cmd_list(&main_cmds, &other_cmds);
305         qsort(main_cmds.names, main_cmds.cnt,
306               sizeof(main_cmds.names), cmdname_compare);
307         uniq(&main_cmds);
309         /* This abuses cmdname->len for levenshtein distance */
310         for (i = 0, n = 0; i < main_cmds.cnt; i++) {
311                 int cmp = 0; /* avoid compiler stupidity */
312                 const char *candidate = main_cmds.names[i]->name;
314                 /*
315                  * An exact match means we have the command, but
316                  * for some reason exec'ing it gave us ENOENT; probably
317                  * it's a bad interpreter in the #! line.
318                  */
319                 if (!strcmp(candidate, cmd))
320                         die(_(bad_interpreter_advice), cmd, cmd);
322                 /* Does the candidate appear in common_cmds list? */
323                 while (n < ARRAY_SIZE(common_cmds) &&
324                        (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
325                         n++;
326                 if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
327                         /* Yes, this is one of the common commands */
328                         n++; /* use the entry from common_cmds[] */
329                         if (!prefixcmp(candidate, cmd)) {
330                                 /* Give prefix match a very good score */
331                                 main_cmds.names[i]->len = 0;
332                                 continue;
333                         }
334                 }
336                 main_cmds.names[i]->len =
337                         levenshtein(cmd, candidate, 0, 2, 1, 4) + 1;
338         }
340         qsort(main_cmds.names, main_cmds.cnt,
341               sizeof(*main_cmds.names), levenshtein_compare);
343         if (!main_cmds.cnt)
344                 die ("Uh oh. Your system reports no Git commands at all.");
346         /* skip and count prefix matches */
347         for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
348                 ; /* still counting */
350         if (main_cmds.cnt <= n) {
351                 /* prefix matches with everything? that is too ambiguous */
352                 best_similarity = SIMILARITY_FLOOR + 1;
353         } else {
354                 /* count all the most similar ones */
355                 for (best_similarity = main_cmds.names[n++]->len;
356                      (n < main_cmds.cnt &&
357                       best_similarity == main_cmds.names[n]->len);
358                      n++)
359                         ; /* still counting */
360         }
361         if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
362                 const char *assumed = main_cmds.names[0]->name;
363                 main_cmds.names[0] = NULL;
364                 clean_cmdnames(&main_cmds);
365                 fprintf(stderr, "WARNING: You called a Git command named '%s', "
366                         "which does not exist.\n"
367                         "Continuing under the assumption that you meant '%s'\n",
368                         cmd, assumed);
369                 if (autocorrect > 0) {
370                         fprintf(stderr, "in %0.1f seconds automatically...\n",
371                                 (float)autocorrect/10.0);
372                         poll(NULL, 0, autocorrect * 100);
373                 }
374                 return assumed;
375         }
377         fprintf(stderr, "git: '%s' is not a git command. See 'git --help'.\n", cmd);
379         if (SIMILAR_ENOUGH(best_similarity)) {
380                 fprintf(stderr, "\nDid you mean %s?\n",
381                         n < 2 ? "this": "one of these");
383                 for (i = 0; i < n; i++)
384                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
385         }
387         exit(1);
390 int cmd_version(int argc, const char **argv, const char *prefix)
392         printf("git version %s\n", git_version_string);
393         return 0;