git wrapper: DWIM mistyped commands
[git/git.git] / help.c
CommitLineData
70827b15
LT
1#include "cache.h"
2#include "builtin.h"
3#include "exec_cmd.h"
8af84dad 4#include "levenshtein.h"
940208a7 5#include "help.h"
64949984 6
82e5a82f 7/* most GUI terminals set COLUMNS (although some don't export it) */
70827b15
LT
8static int term_columns(void)
9{
10 char *col_string = getenv("COLUMNS");
96f1e58f 11 int n_cols;
70827b15
LT
12
13 if (col_string && (n_cols = atoi(col_string)) > 0)
14 return n_cols;
15
16#ifdef TIOCGWINSZ
17 {
18 struct winsize ws;
19 if (!ioctl(1, TIOCGWINSZ, &ws)) {
20 if (ws.ws_col)
21 return ws.ws_col;
22 }
23 }
24#endif
25
26 return 80;
27}
28
940208a7 29void add_cmdname(struct cmdnames *cmds, const char *name, int len)
70827b15 30{
940208a7 31 struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
1eb05690 32
70827b15
LT
33 ent->len = len;
34 memcpy(ent->name, name, len);
35 ent->name[len] = 0;
1eb05690
SP
36
37 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
38 cmds->names[cmds->cnt++] = ent;
70827b15
LT
39}
40
8af84dad
JS
41static void clean_cmdnames(struct cmdnames *cmds)
42{
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;
49}
50
70827b15
LT
51static int cmdname_compare(const void *a_, const void *b_)
52{
53 struct cmdname *a = *(struct cmdname **)a_;
54 struct cmdname *b = *(struct cmdname **)b_;
55 return strcmp(a->name, b->name);
56}
57
1eb05690
SP
58static void uniq(struct cmdnames *cmds)
59{
60 int i, j;
61
62 if (!cmds->cnt)
63 return;
64
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];
68
69 cmds->cnt = j;
70}
71
940208a7 72void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
f3fa1838 73{
1eb05690
SP
74 int ci, cj, ei;
75 int cmp;
76
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++;
86 }
87
88 while (ci < cmds->cnt)
89 cmds->names[cj++] = cmds->names[ci++];
90
91 cmds->cnt = cj;
92}
93
94static void pretty_print_string_list(struct cmdnames *cmds, int longest)
70827b15
LT
95{
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;
100
101 if (space < max_cols)
102 cols = max_cols / space;
1eb05690 103 rows = (cmds->cnt + cols - 1) / cols;
70827b15
LT
104
105 for (i = 0; i < rows; i++) {
106 printf(" ");
107
108 for (j = 0; j < cols; j++) {
109 int n = j * rows + i;
110 int size = space;
1eb05690 111 if (n >= cmds->cnt)
70827b15 112 break;
1eb05690 113 if (j == cols-1 || n + rows >= cmds->cnt)
70827b15 114 size = 1;
1eb05690 115 printf("%-*s", size, cmds->names[n]->name);
70827b15
LT
116 }
117 putchar('\n');
118 }
119}
120
cc3b7a97
JS
121static int is_executable(const char *name)
122{
123 struct stat st;
124
125 if (stat(name, &st) || /* stat, not lstat */
126 !S_ISREG(st.st_mode))
127 return 0;
128
129#ifdef __MINGW32__
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);
142 }
143#endif
144 return st.st_mode & S_IXUSR;
145}
146
1eb05690 147static unsigned int list_commands_in_dir(struct cmdnames *cmds,
940208a7
MV
148 const char *path,
149 const char *prefix)
70827b15
LT
150{
151 unsigned int longest = 0;
940208a7 152 int prefix_len;
1eb05690 153 DIR *dir = opendir(path);
70827b15 154 struct dirent *de;
f5d600e2
JS
155 struct strbuf buf = STRBUF_INIT;
156 int len;
70827b15 157
f5d600e2 158 if (!dir)
1eb05690 159 return 0;
940208a7
MV
160 if (!prefix)
161 prefix = "git-";
162 prefix_len = strlen(prefix);
70827b15 163
f5d600e2
JS
164 strbuf_addf(&buf, "%s/", path);
165 len = buf.len;
166
70827b15 167 while ((de = readdir(dir)) != NULL) {
70827b15
LT
168 int entlen;
169
edb6ddc5 170 if (prefixcmp(de->d_name, prefix))
70827b15 171 continue;
0966003c 172
f5d600e2
JS
173 strbuf_setlen(&buf, len);
174 strbuf_addstr(&buf, de->d_name);
175 if (!is_executable(buf.buf))
70827b15
LT
176 continue;
177
edb6ddc5 178 entlen = strlen(de->d_name) - prefix_len;
5bb1cda5 179 if (has_extension(de->d_name, ".exe"))
70827b15
LT
180 entlen -= 4;
181
182 if (longest < entlen)
183 longest = entlen;
184
1eb05690 185 add_cmdname(cmds, de->d_name + prefix_len, entlen);
70827b15
LT
186 }
187 closedir(dir);
f5d600e2 188 strbuf_release(&buf);
70827b15 189
1eb05690
SP
190 return longest;
191}
192
940208a7
MV
193unsigned int load_command_list(const char *prefix,
194 struct cmdnames *main_cmds,
195 struct cmdnames *other_cmds)
1eb05690
SP
196{
197 unsigned int longest = 0;
198 unsigned int len;
199 const char *env_path = getenv("PATH");
200 char *paths, *path, *colon;
201 const char *exec_path = git_exec_path();
202
203 if (exec_path)
940208a7 204 longest = list_commands_in_dir(main_cmds, exec_path, prefix);
1eb05690
SP
205
206 if (!env_path) {
207 fprintf(stderr, "PATH not set\n");
208 exit(1);
209 }
210
211 path = paths = xstrdup(env_path);
212 while (1) {
cc3b7a97 213 if ((colon = strchr(path, PATH_SEP)))
1eb05690
SP
214 *colon = 0;
215
940208a7 216 len = list_commands_in_dir(other_cmds, path, prefix);
1eb05690
SP
217 if (len > longest)
218 longest = len;
219
220 if (!colon)
221 break;
222 path = colon + 1;
223 }
224 free(paths);
225
940208a7
MV
226 qsort(main_cmds->names, main_cmds->cnt,
227 sizeof(*main_cmds->names), cmdname_compare);
228 uniq(main_cmds);
1eb05690 229
940208a7
MV
230 qsort(other_cmds->names, other_cmds->cnt,
231 sizeof(*other_cmds->names), cmdname_compare);
232 uniq(other_cmds);
233 exclude_cmds(other_cmds, main_cmds);
1eb05690 234
2156435f
JK
235 return longest;
236}
237
940208a7
MV
238void list_commands(const char *title, unsigned int longest,
239 struct cmdnames *main_cmds, struct cmdnames *other_cmds)
2156435f 240{
2156435f
JK
241 const char *exec_path = git_exec_path();
242
940208a7
MV
243 if (main_cmds->cnt) {
244 printf("available %s in '%s'\n", title, exec_path);
245 printf("----------------");
246 mput_char('-', strlen(title) + strlen(exec_path));
1eb05690 247 putchar('\n');
940208a7 248 pretty_print_string_list(main_cmds, longest);
1eb05690
SP
249 putchar('\n');
250 }
251
940208a7
MV
252 if (other_cmds->cnt) {
253 printf("%s available from elsewhere on your $PATH\n", title);
254 printf("---------------------------------------");
255 mput_char('-', strlen(title));
256 putchar('\n');
257 pretty_print_string_list(other_cmds, longest);
1eb05690
SP
258 putchar('\n');
259 }
70827b15
LT
260}
261
940208a7 262int is_in_cmdlist(struct cmdnames *c, const char *s)
2156435f
JK
263{
264 int i;
265 for (i = 0; i < c->cnt; i++)
266 if (!strcmp(s, c->names[i]->name))
267 return 1;
268 return 0;
269}
270
8af84dad
JS
271static int levenshtein_compare(const void *p1, const void *p2)
272{
273 const struct cmdname *const *c1 = p1, *const *c2 = p2;
274 const char *s1 = (*c1)->name, *s2 = (*c2)->name;
275 int l1 = (*c1)->len;
276 int l2 = (*c2)->len;
277 return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
278}
279
280const char *help_unknown_cmd(const char *cmd)
822a7d50 281{
8af84dad
JS
282 int i, n, best_similarity = 0;
283 struct cmdnames main_cmds, other_cmds;
284
285 memset(&main_cmds, 0, sizeof(main_cmds));
286 memset(&other_cmds, 0, sizeof(main_cmds));
287
288 load_command_list("git-", &main_cmds, &other_cmds);
289
290 ALLOC_GROW(main_cmds.names, main_cmds.cnt + other_cmds.cnt,
291 main_cmds.alloc);
292 memcpy(main_cmds.names + main_cmds.cnt, other_cmds.names,
293 other_cmds.cnt * sizeof(other_cmds.names[0]));
294 main_cmds.cnt += other_cmds.cnt;
295 free(other_cmds.names);
296
297 /* This reuses cmdname->len for similarity index */
298 for (i = 0; i < main_cmds.cnt; ++i)
299 main_cmds.names[i]->len =
300 levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
301
302 qsort(main_cmds.names, main_cmds.cnt,
303 sizeof(*main_cmds.names), levenshtein_compare);
304
305 if (!main_cmds.cnt)
306 die ("Uh oh. Your system reports no Git commands at all.");
307
308 best_similarity = main_cmds.names[0]->len;
309 n = 1;
310 while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
311 ++n;
312 if (n == 1) {
313 const char *assumed = main_cmds.names[0]->name;
314 main_cmds.names[0] = NULL;
315 clean_cmdnames(&main_cmds);
316 fprintf(stderr, "WARNING: You called a Git program named '%s', "
317 "which does not exist.\n"
318 "Continuing under the assumption that you meant '%s'\n",
319 cmd, assumed);
320 return assumed;
321 }
322
a238917b 323 fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
8af84dad
JS
324
325 if (best_similarity < 6) {
326 fprintf(stderr, "\nDid you mean %s?\n",
327 n < 2 ? "this": "one of these");
328
329 for (i = 0; i < n; i++)
330 fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
331 }
332
822a7d50
RJ
333 exit(1);
334}
335
a633fca0 336int cmd_version(int argc, const char **argv, const char *prefix)
70827b15
LT
337{
338 printf("git version %s\n", git_version_string);
339 return 0;
340}