40b7e42ae9f87b5cdc7e2f968bbb12caa8f2d01c
[git/git.git] / git.c
1 #include <stdio.h>
2 #include <sys/types.h>
3 #include <sys/stat.h>
4 #include <dirent.h>
5 #include <unistd.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <errno.h>
9 #include <limits.h>
10 #include <stdarg.h>
11 #include <sys/ioctl.h>
12 #include "git-compat-util.h"
13 #include "exec_cmd.h"
14 #include "common-cmds.h"
15
16 #include "cache.h"
17 #include "commit.h"
18 #include "diff.h"
19 #include "revision.h"
20 #include "log-tree.h"
21
22 #ifndef PATH_MAX
23 # define PATH_MAX 4096
24 #endif
25
26 static const char git_usage[] =
27 "Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
28
29 /* most gui terms set COLUMNS (although some don't export it) */
30 static int term_columns(void)
31 {
32 char *col_string = getenv("COLUMNS");
33 int n_cols = 0;
34
35 if (col_string && (n_cols = atoi(col_string)) > 0)
36 return n_cols;
37
38 #ifdef TIOCGWINSZ
39 {
40 struct winsize ws;
41 if (!ioctl(1, TIOCGWINSZ, &ws)) {
42 if (ws.ws_col)
43 return ws.ws_col;
44 }
45 }
46 #endif
47
48 return 80;
49 }
50
51 static void oom(void)
52 {
53 fprintf(stderr, "git: out of memory\n");
54 exit(1);
55 }
56
57 static inline void mput_char(char c, unsigned int num)
58 {
59 while(num--)
60 putchar(c);
61 }
62
63 static struct cmdname {
64 size_t len;
65 char name[1];
66 } **cmdname;
67 static int cmdname_alloc, cmdname_cnt;
68
69 static void add_cmdname(const char *name, int len)
70 {
71 struct cmdname *ent;
72 if (cmdname_alloc <= cmdname_cnt) {
73 cmdname_alloc = cmdname_alloc + 200;
74 cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
75 if (!cmdname)
76 oom();
77 }
78 ent = malloc(sizeof(*ent) + len);
79 if (!ent)
80 oom();
81 ent->len = len;
82 memcpy(ent->name, name, len);
83 ent->name[len] = 0;
84 cmdname[cmdname_cnt++] = ent;
85 }
86
87 static int cmdname_compare(const void *a_, const void *b_)
88 {
89 struct cmdname *a = *(struct cmdname **)a_;
90 struct cmdname *b = *(struct cmdname **)b_;
91 return strcmp(a->name, b->name);
92 }
93
94 static void pretty_print_string_list(struct cmdname **cmdname, int longest)
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;
103 rows = (cmdname_cnt + cols - 1) / cols;
104
105 qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
106
107 for (i = 0; i < rows; i++) {
108 printf(" ");
109
110 for (j = 0; j < cols; j++) {
111 int n = j * rows + i;
112 int size = space;
113 if (n >= cmdname_cnt)
114 break;
115 if (j == cols-1 || n + rows >= cmdname_cnt)
116 size = 1;
117 printf("%-*s", size, cmdname[n]->name);
118 }
119 putchar('\n');
120 }
121 }
122
123 static void list_commands(const char *exec_path, const char *pattern)
124 {
125 unsigned int longest = 0;
126 char path[PATH_MAX];
127 int dirlen;
128 DIR *dir = opendir(exec_path);
129 struct dirent *de;
130
131 if (!dir) {
132 fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
133 exit(1);
134 }
135
136 dirlen = strlen(exec_path);
137 if (PATH_MAX - 20 < dirlen) {
138 fprintf(stderr, "git: insanely long exec-path '%s'\n",
139 exec_path);
140 exit(1);
141 }
142
143 memcpy(path, exec_path, dirlen);
144 path[dirlen++] = '/';
145
146 while ((de = readdir(dir)) != NULL) {
147 struct stat st;
148 int entlen;
149
150 if (strncmp(de->d_name, "git-", 4))
151 continue;
152 strcpy(path+dirlen, de->d_name);
153 if (stat(path, &st) || /* stat, not lstat */
154 !S_ISREG(st.st_mode) ||
155 !(st.st_mode & S_IXUSR))
156 continue;
157
158 entlen = strlen(de->d_name);
159 if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
160 entlen -= 4;
161
162 if (longest < entlen)
163 longest = entlen;
164
165 add_cmdname(de->d_name + 4, entlen-4);
166 }
167 closedir(dir);
168
169 printf("git commands available in '%s'\n", exec_path);
170 printf("----------------------------");
171 mput_char('-', strlen(exec_path));
172 putchar('\n');
173 pretty_print_string_list(cmdname, longest - 4);
174 putchar('\n');
175 }
176
177 static void list_common_cmds_help(void)
178 {
179 int i, longest = 0;
180
181 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
182 if (longest < strlen(common_cmds[i].name))
183 longest = strlen(common_cmds[i].name);
184 }
185
186 puts("The most commonly used git commands are:");
187 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
188 printf(" %s", common_cmds[i].name);
189 mput_char(' ', longest - strlen(common_cmds[i].name) + 4);
190 puts(common_cmds[i].help);
191 }
192 puts("(use 'git help -a' to get a list of all installed git commands)");
193 }
194
195 #ifdef __GNUC__
196 static void cmd_usage(int show_all, const char *exec_path, const char *fmt, ...)
197 __attribute__((__format__(__printf__, 3, 4), __noreturn__));
198 #endif
199 static void cmd_usage(int show_all, const char *exec_path, const char *fmt, ...)
200 {
201 if (fmt) {
202 va_list ap;
203
204 va_start(ap, fmt);
205 printf("git: ");
206 vprintf(fmt, ap);
207 va_end(ap);
208 putchar('\n');
209 }
210 else
211 puts(git_usage);
212
213 if (exec_path) {
214 putchar('\n');
215 if (show_all)
216 list_commands(exec_path, "git-*");
217 else
218 list_common_cmds_help();
219 }
220
221 exit(1);
222 }
223
224 static void prepend_to_path(const char *dir, int len)
225 {
226 char *path, *old_path = getenv("PATH");
227 int path_len = len;
228
229 if (!old_path)
230 old_path = "/usr/local/bin:/usr/bin:/bin";
231
232 path_len = len + strlen(old_path) + 1;
233
234 path = malloc(path_len + 1);
235
236 memcpy(path, dir, len);
237 path[len] = ':';
238 memcpy(path + len + 1, old_path, path_len - len);
239
240 setenv("PATH", path, 1);
241 }
242
243 static void show_man_page(const char *git_cmd)
244 {
245 const char *page;
246
247 if (!strncmp(git_cmd, "git", 3))
248 page = git_cmd;
249 else {
250 int page_len = strlen(git_cmd) + 4;
251 char *p = malloc(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 static int cmd_version(int argc, const char **argv, char **envp)
262 {
263 printf("git version %s\n", GIT_VERSION);
264 return 0;
265 }
266
267 static int cmd_help(int argc, const char **argv, char **envp)
268 {
269 const char *help_cmd = argv[1];
270 if (!help_cmd)
271 cmd_usage(0, git_exec_path(), NULL);
272 else if (!strcmp(help_cmd, "--all") || !strcmp(help_cmd, "-a"))
273 cmd_usage(1, git_exec_path(), NULL);
274 else
275 show_man_page(help_cmd);
276 return 0;
277 }
278
279 static int cmd_log_wc(int argc, const char **argv, char **envp,
280 struct rev_info *rev)
281 {
282 struct commit *commit;
283
284 rev->abbrev = DEFAULT_ABBREV;
285 rev->commit_format = CMIT_FMT_DEFAULT;
286 rev->verbose_header = 1;
287 argc = setup_revisions(argc, argv, rev, "HEAD");
288
289 if (argc > 1)
290 die("unrecognized argument: %s", argv[1]);
291
292 prepare_revision_walk(rev);
293 setup_pager();
294 while ((commit = get_revision(rev)) != NULL) {
295 log_tree_commit(rev, commit);
296 free(commit->buffer);
297 commit->buffer = NULL;
298 }
299 return 0;
300 }
301
302 static int cmd_wc(int argc, const char **argv, char **envp)
303 {
304 struct rev_info rev;
305
306 init_revisions(&rev);
307 rev.diff = 1;
308 rev.diffopt.recursive = 1;
309 return cmd_log_wc(argc, argv, envp, &rev);
310 }
311
312 static int cmd_show(int argc, const char **argv, char **envp)
313 {
314 struct rev_info rev;
315
316 init_revisions(&rev);
317 rev.diff = 1;
318 rev.diffopt.recursive = 1;
319 rev.combine_merges = 1;
320 rev.dense_combined_merges = 1;
321 rev.always_show_header = 1;
322 rev.ignore_merges = 0;
323 rev.no_walk = 1;
324 return cmd_log_wc(argc, argv, envp, &rev);
325 }
326
327 static int cmd_log(int argc, const char **argv, char **envp)
328 {
329 struct rev_info rev;
330
331 init_revisions(&rev);
332 rev.always_show_header = 1;
333 rev.diffopt.recursive = 1;
334 return cmd_log_wc(argc, argv, envp, &rev);
335 }
336
337 static void handle_internal_command(int argc, const char **argv, char **envp)
338 {
339 const char *cmd = argv[0];
340 static struct cmd_struct {
341 const char *cmd;
342 int (*fn)(int, const char **, char **);
343 } commands[] = {
344 { "version", cmd_version },
345 { "help", cmd_help },
346 { "log", cmd_log },
347 { "whatchanged", cmd_wc },
348 { "show", cmd_show },
349 };
350 int i;
351
352 /* Turn "git cmd --help" into "git help cmd" */
353 if (argc > 1 && !strcmp(argv[1], "--help")) {
354 argv[1] = argv[0];
355 argv[0] = cmd = "help";
356 }
357
358 for (i = 0; i < ARRAY_SIZE(commands); i++) {
359 struct cmd_struct *p = commands+i;
360 if (strcmp(p->cmd, cmd))
361 continue;
362 exit(p->fn(argc, argv, envp));
363 }
364 }
365
366 int main(int argc, const char **argv, char **envp)
367 {
368 const char *cmd = argv[0];
369 char *slash = strrchr(cmd, '/');
370 char git_command[PATH_MAX + 1];
371 const char *exec_path = NULL;
372
373 /*
374 * Take the basename of argv[0] as the command
375 * name, and the dirname as the default exec_path
376 * if it's an absolute path and we don't have
377 * anything better.
378 */
379 if (slash) {
380 *slash++ = 0;
381 if (*cmd == '/')
382 exec_path = cmd;
383 cmd = slash;
384 }
385
386 /*
387 * "git-xxxx" is the same as "git xxxx", but we obviously:
388 *
389 * - cannot take flags in between the "git" and the "xxxx".
390 * - cannot execute it externally (since it would just do
391 * the same thing over again)
392 *
393 * So we just directly call the internal command handler, and
394 * die if that one cannot handle it.
395 */
396 if (!strncmp(cmd, "git-", 4)) {
397 cmd += 4;
398 argv[0] = cmd;
399 handle_internal_command(argc, argv, envp);
400 die("cannot handle %s internally", cmd);
401 }
402
403 /* Default command: "help" */
404 cmd = "help";
405
406 /* Look for flags.. */
407 while (argc > 1) {
408 cmd = *++argv;
409 argc--;
410
411 if (strncmp(cmd, "--", 2))
412 break;
413
414 cmd += 2;
415
416 /*
417 * For legacy reasons, the "version" and "help"
418 * commands can be written with "--" prepended
419 * to make them look like flags.
420 */
421 if (!strcmp(cmd, "help"))
422 break;
423 if (!strcmp(cmd, "version"))
424 break;
425
426 /*
427 * Check remaining flags (which by now must be
428 * "--exec-path", but maybe we will accept
429 * other arguments some day)
430 */
431 if (!strncmp(cmd, "exec-path", 9)) {
432 cmd += 9;
433 if (*cmd == '=') {
434 git_set_exec_path(cmd + 1);
435 continue;
436 }
437 puts(git_exec_path());
438 exit(0);
439 }
440 cmd_usage(0, NULL, NULL);
441 }
442 argv[0] = cmd;
443
444 /*
445 * We search for git commands in the following order:
446 * - git_exec_path()
447 * - the path of the "git" command if we could find it
448 * in $0
449 * - the regular PATH.
450 */
451 if (exec_path)
452 prepend_to_path(exec_path, strlen(exec_path));
453 exec_path = git_exec_path();
454 prepend_to_path(exec_path, strlen(exec_path));
455
456 /* See if it's an internal command */
457 handle_internal_command(argc, argv, envp);
458
459 /* .. then try the external ones */
460 execv_git_cmd(argv);
461
462 if (errno == ENOENT)
463 cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
464
465 fprintf(stderr, "Failed to run command '%s': %s\n",
466 git_command, strerror(errno));
467
468 return 1;
469 }