Change to debug mode.
[line.git] / help.c
blob7f4928e45954465d0401964289952aec4bd59e2a
1 #include "cache.h"
2 #include "builtin.h"
3 #include "exec_cmd.h"
4 #include "levenshtein.h"
5 #include "help.h"
7 /* most GUI terminals set COLUMNS (although some don't export it) */
8 static int term_columns(void)
10 char *col_string = getenv("COLUMNS");
11 int n_cols;
13 if (col_string && (n_cols = atoi(col_string)) > 0)
14 return n_cols;
16 #ifdef TIOCGWINSZ
18 struct winsize ws;
19 if (!ioctl(1, TIOCGWINSZ, &ws)) {
20 if (ws.ws_col)
21 return ws.ws_col;
24 #endif
26 return 80;
29 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
31 struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
33 ent->len = len;
34 memcpy(ent->name, name, len);
35 ent->name[len] = 0;
37 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
38 cmds->names[cmds->cnt++] = ent;
41 static void clean_cmdnames(struct cmdnames *cmds)
43 int i;
44 for (i = 0; i < cmds->cnt; ++i)
45 free(cmds->names[i]);
46 free(cmds->names);
47 cmds->cnt = 0;
48 cmds->alloc = 0;
51 static int cmdname_compare(const void *a_, const void *b_)
53 struct cmdname *a = *(struct cmdname **)a_;
54 struct cmdname *b = *(struct cmdname **)b_;
55 return strcmp(a->name, b->name);
58 static void uniq(struct cmdnames *cmds)
60 int i, j;
62 if (!cmds->cnt)
63 return;
65 for (i = j = 1; i < cmds->cnt; i++)
66 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
67 cmds->names[j++] = cmds->names[i];
69 cmds->cnt = j;
72 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
74 int ci, cj, ei;
75 int cmp;
77 ci = cj = ei = 0;
78 while (ci < cmds->cnt && ei < excludes->cnt) {
79 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
80 if (cmp < 0)
81 cmds->names[cj++] = cmds->names[ci++];
82 else if (cmp == 0)
83 ci++, ei++;
84 else if (cmp > 0)
85 ei++;
88 while (ci < cmds->cnt)
89 cmds->names[cj++] = cmds->names[ci++];
91 cmds->cnt = cj;
94 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
96 int cols = 1, rows;
97 int space = longest + 1; /* min 1 SP between words */
98 int max_cols = term_columns() - 1; /* don't print *on* the edge */
99 int i, j;
101 if (space < max_cols)
102 cols = max_cols / space;
103 rows = DIV_ROUND_UP(cmds->cnt, cols);
105 for (i = 0; i < rows; i++) {
106 printf(" ");
108 for (j = 0; j < cols; j++) {
109 int n = j * rows + i;
110 int size = space;
111 if (n >= cmds->cnt)
112 break;
113 if (j == cols-1 || n + rows >= cmds->cnt)
114 size = 1;
115 printf("%-*s", size, cmds->names[n]->name);
117 putchar('\n');
121 static int is_executable(const char *name)
123 struct stat st;
125 if (stat(name, &st) || /* stat, not lstat */
126 !S_ISREG(st.st_mode))
127 return 0;
129 #ifdef WIN32
130 { /* cannot trust the executable bit, peek into the file instead */
131 char buf[3] = { 0 };
132 int n;
133 int fd = open(name, O_RDONLY);
134 st.st_mode &= ~S_IXUSR;
135 if (fd >= 0) {
136 n = read(fd, buf, 2);
137 if (n == 2)
138 /* DOS executables start with "MZ" */
139 if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
140 st.st_mode |= S_IXUSR;
141 close(fd);
144 #endif
145 return st.st_mode & S_IXUSR;
148 static void list_commands_in_dir(struct cmdnames *cmds,
149 const char *path,
150 const char *prefix)
152 int prefix_len;
153 DIR *dir = opendir(path);
154 struct dirent *de;
155 struct strbuf buf = STRBUF_INIT;
156 int len;
158 if (!dir)
159 return;
160 if (!prefix)
161 prefix = "git-";
162 prefix_len = strlen(prefix);
164 strbuf_addf(&buf, "%s/", path);
165 len = buf.len;
167 while ((de = readdir(dir)) != NULL) {
168 int entlen;
170 if (prefixcmp(de->d_name, prefix))
171 continue;
173 strbuf_setlen(&buf, len);
174 strbuf_addstr(&buf, de->d_name);
175 if (!is_executable(buf.buf))
176 continue;
178 entlen = strlen(de->d_name) - prefix_len;
179 if (has_extension(de->d_name, ".exe"))
180 entlen -= 4;
182 add_cmdname(cmds, de->d_name + prefix_len, entlen);
184 closedir(dir);
185 strbuf_release(&buf);
188 void load_command_list(const char *prefix,
189 struct cmdnames *main_cmds,
190 struct cmdnames *other_cmds)
192 const char *env_path = getenv("PATH");
193 const char *exec_path = git_exec_path();
195 if (exec_path) {
196 list_commands_in_dir(main_cmds, exec_path, prefix);
197 qsort(main_cmds->names, main_cmds->cnt,
198 sizeof(*main_cmds->names), cmdname_compare);
199 uniq(main_cmds);
202 if (env_path) {
203 char *paths, *path, *colon;
204 path = paths = xstrdup(env_path);
205 while (1) {
206 if ((colon = strchr(path, PATH_SEP)))
207 *colon = 0;
208 if (!exec_path || strcmp(path, exec_path))
209 list_commands_in_dir(other_cmds, path, prefix);
211 if (!colon)
212 break;
213 path = colon + 1;
215 free(paths);
217 qsort(other_cmds->names, other_cmds->cnt,
218 sizeof(*other_cmds->names), cmdname_compare);
219 uniq(other_cmds);
221 exclude_cmds(other_cmds, main_cmds);
224 void list_commands(const char *title, struct cmdnames *main_cmds,
225 struct cmdnames *other_cmds)
227 int i, longest = 0;
229 for (i = 0; i < main_cmds->cnt; i++)
230 if (longest < main_cmds->names[i]->len)
231 longest = main_cmds->names[i]->len;
232 for (i = 0; i < other_cmds->cnt; i++)
233 if (longest < other_cmds->names[i]->len)
234 longest = other_cmds->names[i]->len;
236 if (main_cmds->cnt) {
237 const char *exec_path = git_exec_path();
238 printf("available %s in '%s'\n", title, exec_path);
239 printf("----------------");
240 mput_char('-', strlen(title) + strlen(exec_path));
241 putchar('\n');
242 pretty_print_string_list(main_cmds, longest);
243 putchar('\n');
246 if (other_cmds->cnt) {
247 printf("%s available from elsewhere on your $PATH\n", title);
248 printf("---------------------------------------");
249 mput_char('-', strlen(title));
250 putchar('\n');
251 pretty_print_string_list(other_cmds, longest);
252 putchar('\n');
256 int is_in_cmdlist(struct cmdnames *c, const char *s)
258 int i;
259 for (i = 0; i < c->cnt; i++)
260 if (!strcmp(s, c->names[i]->name))
261 return 1;
262 return 0;
265 static int autocorrect;
266 static struct cmdnames aliases;
268 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
270 if (!strcmp(var, "help.autocorrect"))
271 autocorrect = git_config_int(var,value);
272 /* Also use aliases for command lookup */
273 if (!prefixcmp(var, "alias."))
274 add_cmdname(&aliases, var + 6, strlen(var + 6));
276 return git_default_config(var, value, cb);
279 static int levenshtein_compare(const void *p1, const void *p2)
281 const struct cmdname *const *c1 = p1, *const *c2 = p2;
282 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
283 int l1 = (*c1)->len;
284 int l2 = (*c2)->len;
285 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
288 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
290 int i;
291 ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
293 for (i = 0; i < old->cnt; i++)
294 cmds->names[cmds->cnt++] = old->names[i];
295 free(old->names);
296 old->cnt = 0;
297 old->names = NULL;
300 /* An empirically derived magic number */
301 #define SIMILAR_ENOUGH(x) ((x) < 6)
303 const char *help_unknown_cmd(const char *cmd)
305 int i, n, best_similarity = 0;
306 struct cmdnames main_cmds, other_cmds;
308 memset(&main_cmds, 0, sizeof(main_cmds));
309 memset(&other_cmds, 0, sizeof(other_cmds));
310 memset(&aliases, 0, sizeof(aliases));
312 git_config(git_unknown_cmd_config, NULL);
314 load_command_list("git-", &main_cmds, &other_cmds);
316 add_cmd_list(&main_cmds, &aliases);
317 add_cmd_list(&main_cmds, &other_cmds);
318 qsort(main_cmds.names, main_cmds.cnt,
319 sizeof(main_cmds.names), cmdname_compare);
320 uniq(&main_cmds);
322 /* This reuses cmdname->len for similarity index */
323 for (i = 0; i < main_cmds.cnt; ++i)
324 main_cmds.names[i]->len =
325 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
327 qsort(main_cmds.names, main_cmds.cnt,
328 sizeof(*main_cmds.names), levenshtein_compare);
330 if (!main_cmds.cnt)
331 die ("Uh oh. Your system reports no Git commands at all.");
333 best_similarity = main_cmds.names[0]->len;
334 n = 1;
335 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
336 ++n;
337 if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
338 const char *assumed = main_cmds.names[0]->name;
339 main_cmds.names[0] = NULL;
340 clean_cmdnames(&main_cmds);
341 fprintf(stderr, "WARNING: You called a Git command named '%s', "
342 "which does not exist.\n"
343 "Continuing under the assumption that you meant '%s'\n",
344 cmd, assumed);
345 if (autocorrect > 0) {
346 fprintf(stderr, "in %0.1f seconds automatically...\n",
347 (float)autocorrect/10.0);
348 poll(NULL, 0, autocorrect * 100);
350 return assumed;
353 fprintf(stderr, "git: '%s' is not a git command. See 'git --help'.\n", cmd);
355 if (SIMILAR_ENOUGH(best_similarity)) {
356 fprintf(stderr, "\nDid you mean %s?\n",
357 n < 2 ? "this": "one of these");
359 for (i = 0; i < n; i++)
360 fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
363 exit(1);
366 int cmd_version(int argc, const char **argv, const char *prefix)
368 printf("git version %s\n", git_version_string);
369 return 0;