contrib/hooks/post-receive-email: remove cruft, $committer is not used
[git/git.git] / help.c
1 /*
2 * builtin-help.c
3 *
4 * Builtin help-related commands (help, usage, version)
5 */
6 #include "cache.h"
7 #include "builtin.h"
8 #include "exec_cmd.h"
9 #include "common-cmds.h"
10 #include <sys/ioctl.h>
11
12 /* most GUI terminals set COLUMNS (although some don't export it) */
13 static int term_columns(void)
14 {
15 char *col_string = getenv("COLUMNS");
16 int n_cols;
17
18 if (col_string && (n_cols = atoi(col_string)) > 0)
19 return n_cols;
20
21 #ifdef TIOCGWINSZ
22 {
23 struct winsize ws;
24 if (!ioctl(1, TIOCGWINSZ, &ws)) {
25 if (ws.ws_col)
26 return ws.ws_col;
27 }
28 }
29 #endif
30
31 return 80;
32 }
33
34 static inline void mput_char(char c, unsigned int num)
35 {
36 while(num--)
37 putchar(c);
38 }
39
40 static struct cmdnames {
41 int alloc;
42 int cnt;
43 struct cmdname {
44 size_t len;
45 char name[1];
46 } **names;
47 } main_cmds, other_cmds;
48
49 static void add_cmdname(struct cmdnames *cmds, const char *name, int len)
50 {
51 struct cmdname *ent = xmalloc(sizeof(*ent) + len);
52
53 ent->len = len;
54 memcpy(ent->name, name, len);
55 ent->name[len] = 0;
56
57 ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
58 cmds->names[cmds->cnt++] = ent;
59 }
60
61 static int cmdname_compare(const void *a_, const void *b_)
62 {
63 struct cmdname *a = *(struct cmdname **)a_;
64 struct cmdname *b = *(struct cmdname **)b_;
65 return strcmp(a->name, b->name);
66 }
67
68 static void uniq(struct cmdnames *cmds)
69 {
70 int i, j;
71
72 if (!cmds->cnt)
73 return;
74
75 for (i = j = 1; i < cmds->cnt; i++)
76 if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
77 cmds->names[j++] = cmds->names[i];
78
79 cmds->cnt = j;
80 }
81
82 static void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes) {
83 int ci, cj, ei;
84 int cmp;
85
86 ci = cj = ei = 0;
87 while (ci < cmds->cnt && ei < excludes->cnt) {
88 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
89 if (cmp < 0)
90 cmds->names[cj++] = cmds->names[ci++];
91 else if (cmp == 0)
92 ci++, ei++;
93 else if (cmp > 0)
94 ei++;
95 }
96
97 while (ci < cmds->cnt)
98 cmds->names[cj++] = cmds->names[ci++];
99
100 cmds->cnt = cj;
101 }
102
103 static void pretty_print_string_list(struct cmdnames *cmds, int longest)
104 {
105 int cols = 1, rows;
106 int space = longest + 1; /* min 1 SP between words */
107 int max_cols = term_columns() - 1; /* don't print *on* the edge */
108 int i, j;
109
110 if (space < max_cols)
111 cols = max_cols / space;
112 rows = (cmds->cnt + cols - 1) / cols;
113
114 for (i = 0; i < rows; i++) {
115 printf(" ");
116
117 for (j = 0; j < cols; j++) {
118 int n = j * rows + i;
119 int size = space;
120 if (n >= cmds->cnt)
121 break;
122 if (j == cols-1 || n + rows >= cmds->cnt)
123 size = 1;
124 printf("%-*s", size, cmds->names[n]->name);
125 }
126 putchar('\n');
127 }
128 }
129
130 static unsigned int list_commands_in_dir(struct cmdnames *cmds,
131 const char *path)
132 {
133 unsigned int longest = 0;
134 const char *prefix = "git-";
135 int prefix_len = strlen(prefix);
136 DIR *dir = opendir(path);
137 struct dirent *de;
138
139 if (!dir || chdir(path))
140 return 0;
141
142 while ((de = readdir(dir)) != NULL) {
143 struct stat st;
144 int entlen;
145
146 if (prefixcmp(de->d_name, prefix))
147 continue;
148
149 if (stat(de->d_name, &st) || /* stat, not lstat */
150 !S_ISREG(st.st_mode) ||
151 !(st.st_mode & S_IXUSR))
152 continue;
153
154 entlen = strlen(de->d_name) - prefix_len;
155 if (has_extension(de->d_name, ".exe"))
156 entlen -= 4;
157
158 if (longest < entlen)
159 longest = entlen;
160
161 add_cmdname(cmds, de->d_name + prefix_len, entlen);
162 }
163 closedir(dir);
164
165 return longest;
166 }
167
168 static void list_commands(void)
169 {
170 unsigned int longest = 0;
171 unsigned int len;
172 const char *env_path = getenv("PATH");
173 char *paths, *path, *colon;
174 const char *exec_path = git_exec_path();
175
176 if (exec_path)
177 longest = list_commands_in_dir(&main_cmds, exec_path);
178
179 if (!env_path) {
180 fprintf(stderr, "PATH not set\n");
181 exit(1);
182 }
183
184 path = paths = xstrdup(env_path);
185 while (1) {
186 if ((colon = strchr(path, ':')))
187 *colon = 0;
188
189 len = list_commands_in_dir(&other_cmds, path);
190 if (len > longest)
191 longest = len;
192
193 if (!colon)
194 break;
195 path = colon + 1;
196 }
197 free(paths);
198
199 qsort(main_cmds.names, main_cmds.cnt,
200 sizeof(*main_cmds.names), cmdname_compare);
201 uniq(&main_cmds);
202
203 qsort(other_cmds.names, other_cmds.cnt,
204 sizeof(*other_cmds.names), cmdname_compare);
205 uniq(&other_cmds);
206 exclude_cmds(&other_cmds, &main_cmds);
207
208 if (main_cmds.cnt) {
209 printf("available git commands in '%s'\n", exec_path);
210 printf("----------------------------");
211 mput_char('-', strlen(exec_path));
212 putchar('\n');
213 pretty_print_string_list(&main_cmds, longest);
214 putchar('\n');
215 }
216
217 if (other_cmds.cnt) {
218 printf("git commands available from elsewhere on your $PATH\n");
219 printf("---------------------------------------------------\n");
220 pretty_print_string_list(&other_cmds, longest);
221 putchar('\n');
222 }
223 }
224
225 void list_common_cmds_help(void)
226 {
227 int i, longest = 0;
228
229 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
230 if (longest < strlen(common_cmds[i].name))
231 longest = strlen(common_cmds[i].name);
232 }
233
234 puts("The most commonly used git commands are:");
235 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
236 printf(" %s ", common_cmds[i].name);
237 mput_char(' ', longest - strlen(common_cmds[i].name));
238 puts(common_cmds[i].help);
239 }
240 puts("(use 'git help -a' to get a list of all installed git commands)");
241 }
242
243 static void show_man_page(const char *git_cmd)
244 {
245 const char *page;
246
247 if (!prefixcmp(git_cmd, "git"))
248 page = git_cmd;
249 else {
250 int page_len = strlen(git_cmd) + 4;
251 char *p = xmalloc(page_len + 1);
252 strcpy(p, "git-");
253 strcpy(p + 4, git_cmd);
254 p[page_len] = 0;
255 page = p;
256 }
257
258 execlp("man", "man", page, NULL);
259 }
260
261 void help_unknown_cmd(const char *cmd)
262 {
263 fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
264 exit(1);
265 }
266
267 int cmd_version(int argc, const char **argv, const char *prefix)
268 {
269 printf("git version %s\n", git_version_string);
270 return 0;
271 }
272
273 int cmd_help(int argc, const char **argv, const char *prefix)
274 {
275 const char *help_cmd = argc > 1 ? argv[1] : NULL;
276
277 if (!help_cmd) {
278 printf("usage: %s\n\n", git_usage_string);
279 list_common_cmds_help();
280 exit(0);
281 }
282
283 else if (!strcmp(help_cmd, "--all") || !strcmp(help_cmd, "-a")) {
284 printf("usage: %s\n\n", git_usage_string);
285 list_commands();
286 exit(0);
287 }
288
289 else
290 show_man_page(help_cmd);
291
292 return 0;
293 }