b8e8622afb8b07f5679b1a5d9d9f74a7b9ade78f
[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 "git-compat-util.h"
12 #include "exec_cmd.h"
13 #include "cache.h"
14 #include "quote.h"
15
16 #include "builtin.h"
17
18 const char git_usage_string[] =
19 "git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate] [--bare] [--git-dir=GIT_DIR] [--help] COMMAND [ARGS]";
20
21 static void prepend_to_path(const char *dir, int len)
22 {
23 const char *old_path = getenv("PATH");
24 char *path;
25 int path_len = len;
26
27 if (!old_path)
28 old_path = "/usr/local/bin:/usr/bin:/bin";
29
30 path_len = len + strlen(old_path) + 1;
31
32 path = xmalloc(path_len + 1);
33
34 memcpy(path, dir, len);
35 path[len] = ':';
36 memcpy(path + len + 1, old_path, path_len - len);
37
38 setenv("PATH", path, 1);
39
40 free(path);
41 }
42
43 static int handle_options(const char*** argv, int* argc)
44 {
45 int handled = 0;
46
47 while (*argc > 0) {
48 const char *cmd = (*argv)[0];
49 if (cmd[0] != '-')
50 break;
51
52 /*
53 * For legacy reasons, the "version" and "help"
54 * commands can be written with "--" prepended
55 * to make them look like flags.
56 */
57 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
58 break;
59
60 /*
61 * Check remaining flags.
62 */
63 if (!strncmp(cmd, "--exec-path", 11)) {
64 cmd += 11;
65 if (*cmd == '=')
66 git_set_exec_path(cmd + 1);
67 else {
68 puts(git_exec_path());
69 exit(0);
70 }
71 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
72 setup_pager();
73 } else if (!strcmp(cmd, "--git-dir")) {
74 if (*argc < 1)
75 return -1;
76 setenv("GIT_DIR", (*argv)[1], 1);
77 (*argv)++;
78 (*argc)--;
79 } else if (!strncmp(cmd, "--git-dir=", 10)) {
80 setenv("GIT_DIR", cmd + 10, 1);
81 } else if (!strcmp(cmd, "--bare")) {
82 static char git_dir[1024];
83 setenv("GIT_DIR", getcwd(git_dir, 1024), 1);
84 } else {
85 fprintf(stderr, "Unknown option: %s\n", cmd);
86 usage(git_usage_string);
87 }
88
89 (*argv)++;
90 (*argc)--;
91 handled++;
92 }
93 return handled;
94 }
95
96 static const char *alias_command;
97 static char *alias_string;
98
99 static int git_alias_config(const char *var, const char *value)
100 {
101 if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
102 alias_string = xstrdup(value);
103 }
104 return 0;
105 }
106
107 static int split_cmdline(char *cmdline, const char ***argv)
108 {
109 int src, dst, count = 0, size = 16;
110 char quoted = 0;
111
112 *argv = malloc(sizeof(char*) * size);
113
114 /* split alias_string */
115 (*argv)[count++] = cmdline;
116 for (src = dst = 0; cmdline[src];) {
117 char c = cmdline[src];
118 if (!quoted && isspace(c)) {
119 cmdline[dst++] = 0;
120 while (cmdline[++src]
121 && isspace(cmdline[src]))
122 ; /* skip */
123 if (count >= size) {
124 size += 16;
125 *argv = xrealloc(*argv, sizeof(char*) * size);
126 }
127 (*argv)[count++] = cmdline + dst;
128 } else if(!quoted && (c == '\'' || c == '"')) {
129 quoted = c;
130 src++;
131 } else if (c == quoted) {
132 quoted = 0;
133 src++;
134 } else {
135 if (c == '\\' && quoted != '\'') {
136 src++;
137 c = cmdline[src];
138 if (!c) {
139 free(*argv);
140 *argv = NULL;
141 return error("cmdline ends with \\");
142 }
143 }
144 cmdline[dst++] = c;
145 src++;
146 }
147 }
148
149 cmdline[dst] = 0;
150
151 if (quoted) {
152 free(*argv);
153 *argv = NULL;
154 return error("unclosed quote");
155 }
156
157 return count;
158 }
159
160 static int handle_alias(int *argcp, const char ***argv)
161 {
162 int nongit = 0, ret = 0, saved_errno = errno;
163 const char *subdir;
164 int count, option_count;
165 const char** new_argv;
166
167 subdir = setup_git_directory_gently(&nongit);
168
169 alias_command = (*argv)[0];
170 git_config(git_alias_config);
171 if (alias_string) {
172 count = split_cmdline(alias_string, &new_argv);
173 option_count = handle_options(&new_argv, &count);
174 memmove(new_argv - option_count, new_argv,
175 count * sizeof(char *));
176 new_argv -= option_count;
177
178 if (count < 1)
179 die("empty alias for %s", alias_command);
180
181 if (!strcmp(alias_command, new_argv[0]))
182 die("recursive alias: %s", alias_command);
183
184 trace_argv_printf(new_argv, count,
185 "trace: alias expansion: %s =>",
186 alias_command);
187
188 new_argv = xrealloc(new_argv, sizeof(char*) *
189 (count + *argcp + 1));
190 /* insert after command name */
191 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
192 new_argv[count+*argcp] = NULL;
193
194 *argv = new_argv;
195 *argcp += count - 1;
196
197 ret = 1;
198 }
199
200 if (subdir)
201 chdir(subdir);
202
203 errno = saved_errno;
204
205 return ret;
206 }
207
208 const char git_version_string[] = GIT_VERSION;
209
210 #define RUN_SETUP (1<<0)
211 #define USE_PAGER (1<<1)
212
213 static void handle_internal_command(int argc, const char **argv, char **envp)
214 {
215 const char *cmd = argv[0];
216 static struct cmd_struct {
217 const char *cmd;
218 int (*fn)(int, const char **, const char *);
219 int option;
220 } commands[] = {
221 { "add", cmd_add, RUN_SETUP },
222 { "apply", cmd_apply },
223 { "archive", cmd_archive },
224 { "cat-file", cmd_cat_file, RUN_SETUP },
225 { "checkout-index", cmd_checkout_index, RUN_SETUP },
226 { "check-ref-format", cmd_check_ref_format },
227 { "commit-tree", cmd_commit_tree, RUN_SETUP },
228 { "count-objects", cmd_count_objects, RUN_SETUP },
229 { "diff", cmd_diff, RUN_SETUP },
230 { "diff-files", cmd_diff_files, RUN_SETUP },
231 { "diff-index", cmd_diff_index, RUN_SETUP },
232 { "diff-stages", cmd_diff_stages, RUN_SETUP },
233 { "diff-tree", cmd_diff_tree, RUN_SETUP },
234 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
235 { "format-patch", cmd_format_patch, RUN_SETUP },
236 { "get-tar-commit-id", cmd_get_tar_commit_id },
237 { "grep", cmd_grep, RUN_SETUP },
238 { "help", cmd_help },
239 { "init-db", cmd_init_db },
240 { "log", cmd_log, RUN_SETUP | USE_PAGER },
241 { "ls-files", cmd_ls_files, RUN_SETUP },
242 { "ls-tree", cmd_ls_tree, RUN_SETUP },
243 { "mailinfo", cmd_mailinfo },
244 { "mailsplit", cmd_mailsplit },
245 { "mv", cmd_mv, RUN_SETUP },
246 { "name-rev", cmd_name_rev, RUN_SETUP },
247 { "pack-objects", cmd_pack_objects, RUN_SETUP },
248 { "prune", cmd_prune, RUN_SETUP },
249 { "prune-packed", cmd_prune_packed, RUN_SETUP },
250 { "push", cmd_push, RUN_SETUP },
251 { "read-tree", cmd_read_tree, RUN_SETUP },
252 { "repo-config", cmd_repo_config },
253 { "rev-list", cmd_rev_list, RUN_SETUP },
254 { "rev-parse", cmd_rev_parse, RUN_SETUP },
255 { "rm", cmd_rm, RUN_SETUP },
256 { "runstatus", cmd_runstatus, RUN_SETUP },
257 { "show-branch", cmd_show_branch, RUN_SETUP },
258 { "show", cmd_show, RUN_SETUP | USE_PAGER },
259 { "stripspace", cmd_stripspace },
260 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
261 { "tar-tree", cmd_tar_tree, RUN_SETUP },
262 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
263 { "update-index", cmd_update_index, RUN_SETUP },
264 { "update-ref", cmd_update_ref, RUN_SETUP },
265 { "upload-archive", cmd_upload_archive },
266 { "version", cmd_version },
267 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
268 { "write-tree", cmd_write_tree, RUN_SETUP },
269 { "verify-pack", cmd_verify_pack },
270 };
271 int i;
272
273 /* Turn "git cmd --help" into "git help cmd" */
274 if (argc > 1 && !strcmp(argv[1], "--help")) {
275 argv[1] = argv[0];
276 argv[0] = cmd = "help";
277 }
278
279 for (i = 0; i < ARRAY_SIZE(commands); i++) {
280 struct cmd_struct *p = commands+i;
281 const char *prefix;
282 if (strcmp(p->cmd, cmd))
283 continue;
284
285 prefix = NULL;
286 if (p->option & RUN_SETUP)
287 prefix = setup_git_directory();
288 if (p->option & USE_PAGER)
289 setup_pager();
290 trace_argv_printf(argv, argc, "trace: built-in: git");
291
292 exit(p->fn(argc, argv, prefix));
293 }
294 }
295
296 int main(int argc, const char **argv, char **envp)
297 {
298 const char *cmd = argv[0] ? argv[0] : "git-help";
299 char *slash = strrchr(cmd, '/');
300 const char *exec_path = NULL;
301 int done_alias = 0;
302
303 /*
304 * Take the basename of argv[0] as the command
305 * name, and the dirname as the default exec_path
306 * if it's an absolute path and we don't have
307 * anything better.
308 */
309 if (slash) {
310 *slash++ = 0;
311 if (*cmd == '/')
312 exec_path = cmd;
313 cmd = slash;
314 }
315
316 /*
317 * "git-xxxx" is the same as "git xxxx", but we obviously:
318 *
319 * - cannot take flags in between the "git" and the "xxxx".
320 * - cannot execute it externally (since it would just do
321 * the same thing over again)
322 *
323 * So we just directly call the internal command handler, and
324 * die if that one cannot handle it.
325 */
326 if (!strncmp(cmd, "git-", 4)) {
327 cmd += 4;
328 argv[0] = cmd;
329 handle_internal_command(argc, argv, envp);
330 die("cannot handle %s internally", cmd);
331 }
332
333 /* Look for flags.. */
334 argv++;
335 argc--;
336 handle_options(&argv, &argc);
337 if (argc > 0) {
338 if (!strncmp(argv[0], "--", 2))
339 argv[0] += 2;
340 } else {
341 /* Default command: "help" */
342 argv[0] = "help";
343 argc = 1;
344 }
345 cmd = argv[0];
346
347 /*
348 * We search for git commands in the following order:
349 * - git_exec_path()
350 * - the path of the "git" command if we could find it
351 * in $0
352 * - the regular PATH.
353 */
354 if (exec_path)
355 prepend_to_path(exec_path, strlen(exec_path));
356 exec_path = git_exec_path();
357 prepend_to_path(exec_path, strlen(exec_path));
358
359 while (1) {
360 /* See if it's an internal command */
361 handle_internal_command(argc, argv, envp);
362
363 /* .. then try the external ones */
364 execv_git_cmd(argv);
365
366 /* It could be an alias -- this works around the insanity
367 * of overriding "git log" with "git show" by having
368 * alias.log = show
369 */
370 if (done_alias || !handle_alias(&argc, &argv))
371 break;
372 done_alias = 1;
373 }
374
375 if (errno == ENOENT)
376 help_unknown_cmd(cmd);
377
378 fprintf(stderr, "Failed to run command '%s': %s\n",
379 cmd, strerror(errno));
380
381 return 1;
382 }