am: Use cat instead of echo to avoid DOS line-endings (fixes t4150)
[git/dscho.git] / help.c
blob69d483d8d3b7e109345b1e8124df6b023ed312fb
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"
10 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
12 struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
14 ent->len = len;
15 memcpy(ent->name, name, len);
16 ent->name[len] = 0;
18 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
19 cmds->names[cmds->cnt++] = ent;
22 static void clean_cmdnames(struct cmdnames *cmds)
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;
32 static int cmdname_compare(const void *a_, const void *b_)
34 struct cmdname *a = *(struct cmdname **)a_;
35 struct cmdname *b = *(struct cmdname **)b_;
36 return strcmp(a->name, b->name);
39 static void uniq(struct cmdnames *cmds)
41 int i, j;
43 if (!cmds->cnt)
44 return;
46 for (i = j = 1; i < cmds->cnt; i++)
47 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
48 cmds->names[j++] = cmds->names[i];
50 cmds->cnt = j;
53 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
55 int ci, cj, ei;
56 int cmp;
58 ci = cj = ei = 0;
59 while (ci < cmds->cnt && ei < excludes->cnt) {
60 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
61 if (cmp < 0)
62 cmds->names[cj++] = cmds->names[ci++];
63 else if (cmp == 0)
64 ci++, ei++;
65 else if (cmp > 0)
66 ei++;
69 while (ci < cmds->cnt)
70 cmds->names[cj++] = cmds->names[ci++];
72 cmds->cnt = cj;
75 static void pretty_print_string_list(struct cmdnames *cmds,
76 unsigned int colopts)
78 struct string_list list = STRING_LIST_INIT_NODUP;
79 struct column_options copts;
80 int i;
82 for (i = 0; i < cmds->cnt; i++)
83 string_list_append(&list, cmds->names[i]->name);
85 * always enable column display, we only consult column.*
86 * about layout strategy and stuff
88 colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
89 memset(&copts, 0, sizeof(copts));
90 copts.indent = " ";
91 copts.padding = 2;
92 print_columns(&list, colopts, &copts);
93 string_list_clear(&list, 0);
96 static int is_executable(const char *name)
98 struct stat st;
100 if (stat(name, &st) || /* stat, not lstat */
101 !S_ISREG(st.st_mode))
102 return 0;
104 #if defined(WIN32) || defined(__CYGWIN__)
105 #if defined(__CYGWIN__)
106 if ((st.st_mode & S_IXUSR) == 0)
107 #endif
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);
122 #endif
123 return st.st_mode & S_IXUSR;
126 static void list_commands_in_dir(struct cmdnames *cmds,
127 const char *path,
128 const char *prefix)
130 int prefix_len;
131 DIR *dir = opendir(path);
132 struct dirent *de;
133 struct strbuf buf = STRBUF_INIT;
134 int len;
136 if (!dir)
137 return;
138 if (!prefix)
139 prefix = "git-";
140 prefix_len = strlen(prefix);
142 strbuf_addf(&buf, "%s/", path);
143 len = buf.len;
145 while ((de = readdir(dir)) != NULL) {
146 int entlen;
148 if (prefixcmp(de->d_name, prefix))
149 continue;
151 strbuf_setlen(&buf, len);
152 strbuf_addstr(&buf, de->d_name);
153 if (!is_executable(buf.buf))
154 continue;
156 entlen = strlen(de->d_name) - prefix_len;
157 if (has_extension(de->d_name, ".exe"))
158 entlen -= 4;
160 add_cmdname(cmds, de->d_name + prefix_len, entlen);
162 closedir(dir);
163 strbuf_release(&buf);
166 void load_command_list(const char *prefix,
167 struct cmdnames *main_cmds,
168 struct cmdnames *other_cmds)
170 const char *env_path = getenv("PATH");
171 const char *exec_path = git_exec_path();
173 if (exec_path) {
174 list_commands_in_dir(main_cmds, exec_path, prefix);
175 qsort(main_cmds->names, main_cmds->cnt,
176 sizeof(*main_cmds->names), cmdname_compare);
177 uniq(main_cmds);
180 if (env_path) {
181 char *paths, *path, *colon;
182 path = paths = xstrdup(env_path);
183 while (1) {
184 if ((colon = strchr(path, PATH_SEP)))
185 *colon = 0;
186 if (!exec_path || strcmp(path, exec_path))
187 list_commands_in_dir(other_cmds, path, prefix);
189 if (!colon)
190 break;
191 path = colon + 1;
193 free(paths);
195 qsort(other_cmds->names, other_cmds->cnt,
196 sizeof(*other_cmds->names), cmdname_compare);
197 uniq(other_cmds);
199 exclude_cmds(other_cmds, main_cmds);
202 void list_commands(unsigned int colopts,
203 struct cmdnames *main_cmds, struct cmdnames *other_cmds)
205 if (main_cmds->cnt) {
206 const char *exec_path = git_exec_path();
207 printf_ln(_("available git commands in '%s'"), exec_path);
208 putchar('\n');
209 pretty_print_string_list(main_cmds, colopts);
210 putchar('\n');
213 if (other_cmds->cnt) {
214 printf_ln(_("git commands available from elsewhere on your $PATH"));
215 putchar('\n');
216 pretty_print_string_list(other_cmds, colopts);
217 putchar('\n');
221 int is_in_cmdlist(struct cmdnames *c, const char *s)
223 int i;
224 for (i = 0; i < c->cnt; i++)
225 if (!strcmp(s, c->names[i]->name))
226 return 1;
227 return 0;
230 static int autocorrect;
231 static struct cmdnames aliases;
233 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
235 if (!strcmp(var, "help.autocorrect"))
236 autocorrect = git_config_int(var,value);
237 /* Also use aliases for command lookup */
238 if (!prefixcmp(var, "alias."))
239 add_cmdname(&aliases, var + 6, strlen(var + 6));
241 return git_default_config(var, value, cb);
244 static int levenshtein_compare(const void *p1, const void *p2)
246 const struct cmdname *const *c1 = p1, *const *c2 = p2;
247 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
248 int l1 = (*c1)->len;
249 int l2 = (*c2)->len;
250 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
253 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
255 int i;
256 ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
258 for (i = 0; i < old->cnt; i++)
259 cmds->names[cmds->cnt++] = old->names[i];
260 free(old->names);
261 old->cnt = 0;
262 old->names = NULL;
265 /* An empirically derived magic number */
266 #define SIMILARITY_FLOOR 7
267 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
269 static const char bad_interpreter_advice[] =
270 N_("'%s' appears to be a git command, but we were not\n"
271 "able to execute it. Maybe git-%s is broken?");
273 const char *help_unknown_cmd(const char *cmd)
275 int i, n, best_similarity = 0;
276 struct cmdnames main_cmds, other_cmds;
278 memset(&main_cmds, 0, sizeof(main_cmds));
279 memset(&other_cmds, 0, sizeof(other_cmds));
280 memset(&aliases, 0, sizeof(aliases));
282 git_config(git_unknown_cmd_config, NULL);
284 load_command_list("git-", &main_cmds, &other_cmds);
286 add_cmd_list(&main_cmds, &aliases);
287 add_cmd_list(&main_cmds, &other_cmds);
288 qsort(main_cmds.names, main_cmds.cnt,
289 sizeof(main_cmds.names), cmdname_compare);
290 uniq(&main_cmds);
292 /* This abuses cmdname->len for levenshtein distance */
293 for (i = 0, n = 0; i < main_cmds.cnt; i++) {
294 int cmp = 0; /* avoid compiler stupidity */
295 const char *candidate = main_cmds.names[i]->name;
298 * An exact match means we have the command, but
299 * for some reason exec'ing it gave us ENOENT; probably
300 * it's a bad interpreter in the #! line.
302 if (!strcmp(candidate, cmd))
303 die(_(bad_interpreter_advice), cmd, cmd);
305 /* Does the candidate appear in common_cmds list? */
306 while (n < ARRAY_SIZE(common_cmds) &&
307 (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
308 n++;
309 if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
310 /* Yes, this is one of the common commands */
311 n++; /* use the entry from common_cmds[] */
312 if (!prefixcmp(candidate, cmd)) {
313 /* Give prefix match a very good score */
314 main_cmds.names[i]->len = 0;
315 continue;
319 main_cmds.names[i]->len =
320 levenshtein(cmd, candidate, 0, 2, 1, 4) + 1;
323 qsort(main_cmds.names, main_cmds.cnt,
324 sizeof(*main_cmds.names), levenshtein_compare);
326 if (!main_cmds.cnt)
327 die(_("Uh oh. Your system reports no Git commands at all."));
329 /* skip and count prefix matches */
330 for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
331 ; /* still counting */
333 if (main_cmds.cnt <= n) {
334 /* prefix matches with everything? that is too ambiguous */
335 best_similarity = SIMILARITY_FLOOR + 1;
336 } else {
337 /* count all the most similar ones */
338 for (best_similarity = main_cmds.names[n++]->len;
339 (n < main_cmds.cnt &&
340 best_similarity == main_cmds.names[n]->len);
341 n++)
342 ; /* still counting */
344 if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
345 const char *assumed = main_cmds.names[0]->name;
346 main_cmds.names[0] = NULL;
347 clean_cmdnames(&main_cmds);
348 fprintf_ln(stderr,
349 _("WARNING: You called a Git command named '%s', "
350 "which does not exist.\n"
351 "Continuing under the assumption that you meant '%s'"),
352 cmd, assumed);
353 if (autocorrect > 0) {
354 fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
355 (float)autocorrect/10.0);
356 poll(NULL, 0, autocorrect * 100);
358 return assumed;
361 fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
363 if (SIMILAR_ENOUGH(best_similarity)) {
364 fprintf_ln(stderr,
365 Q_("\nDid you mean this?",
366 "\nDid you mean one of these?",
367 n));
369 for (i = 0; i < n; i++)
370 fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
373 exit(1);
376 int cmd_version(int argc, const char **argv, const char *prefix)
378 printf("git version %s\n", git_version_string);
379 return 0;