user-manual: fix .gitconfig editing examples
[git] / git.c
1 #include "builtin.h"
2 #include "exec_cmd.h"
3 #include "cache.h"
4 #include "quote.h"
5
6 const char git_usage_string[] =
7         "git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate] [--bare] [--git-dir=GIT_DIR] [--help] COMMAND [ARGS]";
8
9 static void prepend_to_path(const char *dir, int len)
10 {
11         const char *old_path = getenv("PATH");
12         char *path;
13         int path_len = len;
14
15         if (!old_path)
16                 old_path = "/usr/local/bin:/usr/bin:/bin";
17
18         path_len = len + strlen(old_path) + 1;
19
20         path = xmalloc(path_len + 1);
21
22         memcpy(path, dir, len);
23         path[len] = ':';
24         memcpy(path + len + 1, old_path, path_len - len);
25
26         setenv("PATH", path, 1);
27
28         free(path);
29 }
30
31 static int handle_options(const char*** argv, int* argc)
32 {
33         int handled = 0;
34
35         while (*argc > 0) {
36                 const char *cmd = (*argv)[0];
37                 if (cmd[0] != '-')
38                         break;
39
40                 /*
41                  * For legacy reasons, the "version" and "help"
42                  * commands can be written with "--" prepended
43                  * to make them look like flags.
44                  */
45                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
46                         break;
47
48                 /*
49                  * Check remaining flags.
50                  */
51                 if (!prefixcmp(cmd, "--exec-path")) {
52                         cmd += 11;
53                         if (*cmd == '=')
54                                 git_set_exec_path(cmd + 1);
55                         else {
56                                 puts(git_exec_path());
57                                 exit(0);
58                         }
59                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
60                         setup_pager();
61                 } else if (!strcmp(cmd, "--git-dir")) {
62                         if (*argc < 2) {
63                                 fprintf(stderr, "No directory given for --git-dir.\n" );
64                                 usage(git_usage_string);
65                         }
66                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
67                         (*argv)++;
68                         (*argc)--;
69                         handled++;
70                 } else if (!prefixcmp(cmd, "--git-dir=")) {
71                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
72                 } else if (!strcmp(cmd, "--bare")) {
73                         static char git_dir[PATH_MAX+1];
74                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 1);
75                 } else {
76                         fprintf(stderr, "Unknown option: %s\n", cmd);
77                         usage(git_usage_string);
78                 }
79
80                 (*argv)++;
81                 (*argc)--;
82                 handled++;
83         }
84         return handled;
85 }
86
87 static const char *alias_command;
88 static char *alias_string;
89
90 static int git_alias_config(const char *var, const char *value)
91 {
92         if (!prefixcmp(var, "alias.") && !strcmp(var + 6, alias_command)) {
93                 alias_string = xstrdup(value);
94         }
95         return 0;
96 }
97
98 static int split_cmdline(char *cmdline, const char ***argv)
99 {
100         int src, dst, count = 0, size = 16;
101         char quoted = 0;
102
103         *argv = xmalloc(sizeof(char*) * size);
104
105         /* split alias_string */
106         (*argv)[count++] = cmdline;
107         for (src = dst = 0; cmdline[src];) {
108                 char c = cmdline[src];
109                 if (!quoted && isspace(c)) {
110                         cmdline[dst++] = 0;
111                         while (cmdline[++src]
112                                         && isspace(cmdline[src]))
113                                 ; /* skip */
114                         if (count >= size) {
115                                 size += 16;
116                                 *argv = xrealloc(*argv, sizeof(char*) * size);
117                         }
118                         (*argv)[count++] = cmdline + dst;
119                 } else if(!quoted && (c == '\'' || c == '"')) {
120                         quoted = c;
121                         src++;
122                 } else if (c == quoted) {
123                         quoted = 0;
124                         src++;
125                 } else {
126                         if (c == '\\' && quoted != '\'') {
127                                 src++;
128                                 c = cmdline[src];
129                                 if (!c) {
130                                         free(*argv);
131                                         *argv = NULL;
132                                         return error("cmdline ends with \\");
133                                 }
134                         }
135                         cmdline[dst++] = c;
136                         src++;
137                 }
138         }
139
140         cmdline[dst] = 0;
141
142         if (quoted) {
143                 free(*argv);
144                 *argv = NULL;
145                 return error("unclosed quote");
146         }
147
148         return count;
149 }
150
151 static int handle_alias(int *argcp, const char ***argv)
152 {
153         int nongit = 0, ret = 0, saved_errno = errno;
154         const char *subdir;
155         int count, option_count;
156         const char** new_argv;
157
158         subdir = setup_git_directory_gently(&nongit);
159
160         alias_command = (*argv)[0];
161         git_config(git_alias_config);
162         if (alias_string) {
163                 if (alias_string[0] == '!') {
164                         trace_printf("trace: alias to shell cmd: %s => %s\n",
165                                      alias_command, alias_string + 1);
166                         ret = system(alias_string + 1);
167                         if (ret >= 0 && WIFEXITED(ret) &&
168                             WEXITSTATUS(ret) != 127)
169                                 exit(WEXITSTATUS(ret));
170                         die("Failed to run '%s' when expanding alias '%s'\n",
171                             alias_string + 1, alias_command);
172                 }
173                 count = split_cmdline(alias_string, &new_argv);
174                 option_count = handle_options(&new_argv, &count);
175                 memmove(new_argv - option_count, new_argv,
176                                 count * sizeof(char *));
177                 new_argv -= option_count;
178
179                 if (count < 1)
180                         die("empty alias for %s", alias_command);
181
182                 if (!strcmp(alias_command, new_argv[0]))
183                         die("recursive alias: %s", alias_command);
184
185                 trace_argv_printf(new_argv, count,
186                                   "trace: alias expansion: %s =>",
187                                   alias_command);
188
189                 new_argv = xrealloc(new_argv, sizeof(char*) *
190                                     (count + *argcp + 1));
191                 /* insert after command name */
192                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
193                 new_argv[count+*argcp] = NULL;
194
195                 *argv = new_argv;
196                 *argcp += count - 1;
197
198                 ret = 1;
199         }
200
201         if (subdir)
202                 chdir(subdir);
203
204         errno = saved_errno;
205
206         return ret;
207 }
208
209 const char git_version_string[] = GIT_VERSION;
210
211 #define RUN_SETUP       (1<<0)
212 #define USE_PAGER       (1<<1)
213 /*
214  * require working tree to be present -- anything uses this needs
215  * RUN_SETUP for reading from the configuration file.
216  */
217 #define NOT_BARE        (1<<2)
218
219 static void handle_internal_command(int argc, const char **argv, char **envp)
220 {
221         const char *cmd = argv[0];
222         static struct cmd_struct {
223                 const char *cmd;
224                 int (*fn)(int, const char **, const char *);
225                 int option;
226         } commands[] = {
227                 { "add", cmd_add, RUN_SETUP | NOT_BARE },
228                 { "annotate", cmd_annotate, USE_PAGER },
229                 { "apply", cmd_apply },
230                 { "archive", cmd_archive },
231                 { "blame", cmd_blame, RUN_SETUP },
232                 { "branch", cmd_branch, RUN_SETUP },
233                 { "bundle", cmd_bundle },
234                 { "cat-file", cmd_cat_file, RUN_SETUP },
235                 { "checkout-index", cmd_checkout_index, RUN_SETUP },
236                 { "check-ref-format", cmd_check_ref_format },
237                 { "cherry", cmd_cherry, RUN_SETUP },
238                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NOT_BARE },
239                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
240                 { "config", cmd_config },
241                 { "count-objects", cmd_count_objects, RUN_SETUP },
242                 { "describe", cmd_describe, RUN_SETUP },
243                 { "diff", cmd_diff, USE_PAGER },
244                 { "diff-files", cmd_diff_files },
245                 { "diff-index", cmd_diff_index, RUN_SETUP },
246                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
247                 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
248                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
249                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
250                 { "format-patch", cmd_format_patch, RUN_SETUP },
251                 { "fsck", cmd_fsck, RUN_SETUP },
252                 { "fsck-objects", cmd_fsck, RUN_SETUP },
253                 { "gc", cmd_gc, RUN_SETUP },
254                 { "get-tar-commit-id", cmd_get_tar_commit_id },
255                 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
256                 { "help", cmd_help },
257                 { "init", cmd_init_db },
258                 { "init-db", cmd_init_db },
259                 { "log", cmd_log, RUN_SETUP | USE_PAGER },
260                 { "ls-files", cmd_ls_files, RUN_SETUP },
261                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
262                 { "mailinfo", cmd_mailinfo },
263                 { "mailsplit", cmd_mailsplit },
264                 { "merge-base", cmd_merge_base, RUN_SETUP },
265                 { "merge-file", cmd_merge_file },
266                 { "mv", cmd_mv, RUN_SETUP | NOT_BARE },
267                 { "name-rev", cmd_name_rev, RUN_SETUP },
268                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
269                 { "pickaxe", cmd_blame, RUN_SETUP | USE_PAGER },
270                 { "prune", cmd_prune, RUN_SETUP },
271                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
272                 { "push", cmd_push, RUN_SETUP },
273                 { "read-tree", cmd_read_tree, RUN_SETUP },
274                 { "reflog", cmd_reflog, RUN_SETUP },
275                 { "repo-config", cmd_config },
276                 { "rerere", cmd_rerere, RUN_SETUP },
277                 { "rev-list", cmd_rev_list, RUN_SETUP },
278                 { "rev-parse", cmd_rev_parse, RUN_SETUP },
279                 { "revert", cmd_revert, RUN_SETUP | NOT_BARE },
280                 { "rm", cmd_rm, RUN_SETUP | NOT_BARE },
281                 { "runstatus", cmd_runstatus, RUN_SETUP | NOT_BARE },
282                 { "shortlog", cmd_shortlog, RUN_SETUP | USE_PAGER },
283                 { "show-branch", cmd_show_branch, RUN_SETUP },
284                 { "show", cmd_show, RUN_SETUP | USE_PAGER },
285                 { "stripspace", cmd_stripspace },
286                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
287                 { "tar-tree", cmd_tar_tree },
288                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
289                 { "update-index", cmd_update_index, RUN_SETUP },
290                 { "update-ref", cmd_update_ref, RUN_SETUP },
291                 { "upload-archive", cmd_upload_archive },
292                 { "version", cmd_version },
293                 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
294                 { "write-tree", cmd_write_tree, RUN_SETUP },
295                 { "verify-pack", cmd_verify_pack },
296                 { "show-ref", cmd_show_ref, RUN_SETUP },
297                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
298         };
299         int i;
300
301         /* Turn "git cmd --help" into "git help cmd" */
302         if (argc > 1 && !strcmp(argv[1], "--help")) {
303                 argv[1] = argv[0];
304                 argv[0] = cmd = "help";
305         }
306
307         for (i = 0; i < ARRAY_SIZE(commands); i++) {
308                 struct cmd_struct *p = commands+i;
309                 const char *prefix;
310                 if (strcmp(p->cmd, cmd))
311                         continue;
312
313                 prefix = NULL;
314                 if (p->option & RUN_SETUP)
315                         prefix = setup_git_directory();
316                 if (p->option & USE_PAGER)
317                         setup_pager();
318                 if ((p->option & NOT_BARE) &&
319                                 (is_bare_repository() || is_inside_git_dir()))
320                         die("%s must be run in a work tree", cmd);
321                 trace_argv_printf(argv, argc, "trace: built-in: git");
322
323                 exit(p->fn(argc, argv, prefix));
324         }
325 }
326
327 int main(int argc, const char **argv, char **envp)
328 {
329         const char *cmd = argv[0] ? argv[0] : "git-help";
330         char *slash = strrchr(cmd, '/');
331         const char *exec_path = NULL;
332         int done_alias = 0;
333
334         /*
335          * Take the basename of argv[0] as the command
336          * name, and the dirname as the default exec_path
337          * if it's an absolute path and we don't have
338          * anything better.
339          */
340         if (slash) {
341                 *slash++ = 0;
342                 if (*cmd == '/')
343                         exec_path = cmd;
344                 cmd = slash;
345         }
346
347         /*
348          * "git-xxxx" is the same as "git xxxx", but we obviously:
349          *
350          *  - cannot take flags in between the "git" and the "xxxx".
351          *  - cannot execute it externally (since it would just do
352          *    the same thing over again)
353          *
354          * So we just directly call the internal command handler, and
355          * die if that one cannot handle it.
356          */
357         if (!prefixcmp(cmd, "git-")) {
358                 cmd += 4;
359                 argv[0] = cmd;
360                 handle_internal_command(argc, argv, envp);
361                 die("cannot handle %s internally", cmd);
362         }
363
364         /* Look for flags.. */
365         argv++;
366         argc--;
367         handle_options(&argv, &argc);
368         if (argc > 0) {
369                 if (!prefixcmp(argv[0], "--"))
370                         argv[0] += 2;
371         } else {
372                 /* Default command: "help" */
373                 argv[0] = "help";
374                 argc = 1;
375         }
376         cmd = argv[0];
377
378         /*
379          * We search for git commands in the following order:
380          *  - git_exec_path()
381          *  - the path of the "git" command if we could find it
382          *    in $0
383          *  - the regular PATH.
384          */
385         if (exec_path)
386                 prepend_to_path(exec_path, strlen(exec_path));
387         exec_path = git_exec_path();
388         prepend_to_path(exec_path, strlen(exec_path));
389
390         while (1) {
391                 /* See if it's an internal command */
392                 handle_internal_command(argc, argv, envp);
393
394                 /* .. then try the external ones */
395                 execv_git_cmd(argv);
396
397                 /* It could be an alias -- this works around the insanity
398                  * of overriding "git log" with "git show" by having
399                  * alias.log = show
400                  */
401                 if (done_alias || !handle_alias(&argc, &argv))
402                         break;
403                 done_alias = 1;
404         }
405
406         if (errno == ENOENT) {
407                 if (done_alias) {
408                         fprintf(stderr, "Expansion of alias '%s' failed; "
409                                 "'%s' is not a git-command\n",
410                                 cmd, argv[0]);
411                         exit(1);
412                 }
413                 help_unknown_cmd(cmd);
414         }
415
416         fprintf(stderr, "Failed to run command '%s': %s\n",
417                 cmd, strerror(errno));
418
419         return 1;
420 }