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