config: add test cases for empty value and no value config variables.
[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|--no-pager] [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE] [--help] COMMAND [ARGS]";
8
9 static int handle_options(const char*** argv, int* argc, int* envchanged)
10 {
11         int handled = 0;
12
13         while (*argc > 0) {
14                 const char *cmd = (*argv)[0];
15                 if (cmd[0] != '-')
16                         break;
17
18                 /*
19                  * For legacy reasons, the "version" and "help"
20                  * commands can be written with "--" prepended
21                  * to make them look like flags.
22                  */
23                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
24                         break;
25
26                 /*
27                  * Check remaining flags.
28                  */
29                 if (!prefixcmp(cmd, "--exec-path")) {
30                         cmd += 11;
31                         if (*cmd == '=')
32                                 git_set_argv_exec_path(cmd + 1);
33                         else {
34                                 puts(git_exec_path());
35                                 exit(0);
36                         }
37                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
38                         setup_pager();
39                 } else if (!strcmp(cmd, "--no-pager")) {
40                         setenv("GIT_PAGER", "cat", 1);
41                         if (envchanged)
42                                 *envchanged = 1;
43                 } else if (!strcmp(cmd, "--git-dir")) {
44                         if (*argc < 2) {
45                                 fprintf(stderr, "No directory given for --git-dir.\n" );
46                                 usage(git_usage_string);
47                         }
48                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
49                         if (envchanged)
50                                 *envchanged = 1;
51                         (*argv)++;
52                         (*argc)--;
53                         handled++;
54                 } else if (!prefixcmp(cmd, "--git-dir=")) {
55                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
56                         if (envchanged)
57                                 *envchanged = 1;
58                 } else if (!strcmp(cmd, "--work-tree")) {
59                         if (*argc < 2) {
60                                 fprintf(stderr, "No directory given for --work-tree.\n" );
61                                 usage(git_usage_string);
62                         }
63                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
64                         if (envchanged)
65                                 *envchanged = 1;
66                         (*argv)++;
67                         (*argc)--;
68                 } else if (!prefixcmp(cmd, "--work-tree=")) {
69                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
70                         if (envchanged)
71                                 *envchanged = 1;
72                 } else if (!strcmp(cmd, "--bare")) {
73                         static char git_dir[PATH_MAX+1];
74                         is_bare_repository_cfg = 1;
75                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
76                         if (envchanged)
77                                 *envchanged = 1;
78                 } else {
79                         fprintf(stderr, "Unknown option: %s\n", cmd);
80                         usage(git_usage_string);
81                 }
82
83                 (*argv)++;
84                 (*argc)--;
85                 handled++;
86         }
87         return handled;
88 }
89
90 static const char *alias_command;
91 static char *alias_string;
92
93 static int git_alias_config(const char *var, const char *value)
94 {
95         if (!prefixcmp(var, "alias.") && !strcmp(var + 6, alias_command)) {
96                 alias_string = xstrdup(value);
97         }
98         return 0;
99 }
100
101 static int split_cmdline(char *cmdline, const char ***argv)
102 {
103         int src, dst, count = 0, size = 16;
104         char quoted = 0;
105
106         *argv = xmalloc(sizeof(char*) * size);
107
108         /* split alias_string */
109         (*argv)[count++] = cmdline;
110         for (src = dst = 0; cmdline[src];) {
111                 char c = cmdline[src];
112                 if (!quoted && isspace(c)) {
113                         cmdline[dst++] = 0;
114                         while (cmdline[++src]
115                                         && isspace(cmdline[src]))
116                                 ; /* skip */
117                         if (count >= size) {
118                                 size += 16;
119                                 *argv = xrealloc(*argv, sizeof(char*) * size);
120                         }
121                         (*argv)[count++] = cmdline + dst;
122                 } else if(!quoted && (c == '\'' || c == '"')) {
123                         quoted = c;
124                         src++;
125                 } else if (c == quoted) {
126                         quoted = 0;
127                         src++;
128                 } else {
129                         if (c == '\\' && quoted != '\'') {
130                                 src++;
131                                 c = cmdline[src];
132                                 if (!c) {
133                                         free(*argv);
134                                         *argv = NULL;
135                                         return error("cmdline ends with \\");
136                                 }
137                         }
138                         cmdline[dst++] = c;
139                         src++;
140                 }
141         }
142
143         cmdline[dst] = 0;
144
145         if (quoted) {
146                 free(*argv);
147                 *argv = NULL;
148                 return error("unclosed quote");
149         }
150
151         return count;
152 }
153
154 static int handle_alias(int *argcp, const char ***argv)
155 {
156         int nongit = 0, envchanged = 0, ret = 0, saved_errno = errno;
157         const char *subdir;
158         int count, option_count;
159         const char** new_argv;
160
161         subdir = setup_git_directory_gently(&nongit);
162
163         alias_command = (*argv)[0];
164         git_config(git_alias_config);
165         if (alias_string) {
166                 if (alias_string[0] == '!') {
167                         if (*argcp > 1) {
168                                 struct strbuf buf;
169
170                                 strbuf_init(&buf, PATH_MAX);
171                                 strbuf_addstr(&buf, alias_string);
172                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
173                                 free(alias_string);
174                                 alias_string = buf.buf;
175                         }
176                         trace_printf("trace: alias to shell cmd: %s => %s\n",
177                                      alias_command, alias_string + 1);
178                         ret = system(alias_string + 1);
179                         if (ret >= 0 && WIFEXITED(ret) &&
180                             WEXITSTATUS(ret) != 127)
181                                 exit(WEXITSTATUS(ret));
182                         die("Failed to run '%s' when expanding alias '%s'\n",
183                             alias_string + 1, alias_command);
184                 }
185                 count = split_cmdline(alias_string, &new_argv);
186                 option_count = handle_options(&new_argv, &count, &envchanged);
187                 if (envchanged)
188                         die("alias '%s' changes environment variables\n"
189                                  "You can use '!git' in the alias to do this.",
190                                  alias_command);
191                 memmove(new_argv - option_count, new_argv,
192                                 count * sizeof(char *));
193                 new_argv -= option_count;
194
195                 if (count < 1)
196                         die("empty alias for %s", alias_command);
197
198                 if (!strcmp(alias_command, new_argv[0]))
199                         die("recursive alias: %s", alias_command);
200
201                 trace_argv_printf(new_argv,
202                                   "trace: alias expansion: %s =>",
203                                   alias_command);
204
205                 new_argv = xrealloc(new_argv, sizeof(char*) *
206                                     (count + *argcp + 1));
207                 /* insert after command name */
208                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
209                 new_argv[count+*argcp] = NULL;
210
211                 *argv = new_argv;
212                 *argcp += count - 1;
213
214                 ret = 1;
215         }
216
217         if (subdir)
218                 chdir(subdir);
219
220         errno = saved_errno;
221
222         return ret;
223 }
224
225 const char git_version_string[] = GIT_VERSION;
226
227 #define RUN_SETUP       (1<<0)
228 #define USE_PAGER       (1<<1)
229 /*
230  * require working tree to be present -- anything uses this needs
231  * RUN_SETUP for reading from the configuration file.
232  */
233 #define NEED_WORK_TREE  (1<<2)
234
235 struct cmd_struct {
236         const char *cmd;
237         int (*fn)(int, const char **, const char *);
238         int option;
239 };
240
241 static int run_command(struct cmd_struct *p, int argc, const char **argv)
242 {
243         int status;
244         struct stat st;
245         const char *prefix;
246
247         prefix = NULL;
248         if (p->option & RUN_SETUP)
249                 prefix = setup_git_directory();
250         if (p->option & USE_PAGER)
251                 setup_pager();
252         if (p->option & NEED_WORK_TREE)
253                 setup_work_tree();
254
255         trace_argv_printf(argv, "trace: built-in: git");
256
257         status = p->fn(argc, argv, prefix);
258         if (status)
259                 return status & 0xff;
260
261         /* Somebody closed stdout? */
262         if (fstat(fileno(stdout), &st))
263                 return 0;
264         /* Ignore write errors for pipes and sockets.. */
265         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
266                 return 0;
267
268         /* Check for ENOSPC and EIO errors.. */
269         if (fflush(stdout))
270                 die("write failure on standard output: %s", strerror(errno));
271         if (ferror(stdout))
272                 die("unknown write failure on standard output");
273         if (fclose(stdout))
274                 die("close failed on standard output: %s", strerror(errno));
275         return 0;
276 }
277
278 static void handle_internal_command(int argc, const char **argv)
279 {
280         const char *cmd = argv[0];
281         static struct cmd_struct commands[] = {
282                 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
283                 { "annotate", cmd_annotate, RUN_SETUP },
284                 { "apply", cmd_apply },
285                 { "archive", cmd_archive },
286                 { "blame", cmd_blame, RUN_SETUP },
287                 { "branch", cmd_branch, RUN_SETUP },
288                 { "bundle", cmd_bundle },
289                 { "cat-file", cmd_cat_file, RUN_SETUP },
290                 { "checkout-index", cmd_checkout_index,
291                         RUN_SETUP | NEED_WORK_TREE},
292                 { "check-ref-format", cmd_check_ref_format },
293                 { "check-attr", cmd_check_attr, RUN_SETUP | NEED_WORK_TREE },
294                 { "cherry", cmd_cherry, RUN_SETUP },
295                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
296                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
297                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
298                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
299                 { "config", cmd_config },
300                 { "count-objects", cmd_count_objects, RUN_SETUP },
301                 { "describe", cmd_describe, RUN_SETUP },
302                 { "diff", cmd_diff },
303                 { "diff-files", cmd_diff_files },
304                 { "diff-index", cmd_diff_index, RUN_SETUP },
305                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
306                 { "fast-export", cmd_fast_export, RUN_SETUP },
307                 { "fetch", cmd_fetch, RUN_SETUP },
308                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
309                 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
310                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
311                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
312                 { "format-patch", cmd_format_patch, RUN_SETUP },
313                 { "fsck", cmd_fsck, RUN_SETUP },
314                 { "fsck-objects", cmd_fsck, RUN_SETUP },
315                 { "gc", cmd_gc, RUN_SETUP },
316                 { "get-tar-commit-id", cmd_get_tar_commit_id },
317                 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
318                 { "help", cmd_help },
319 #ifndef NO_CURL
320                 { "http-fetch", cmd_http_fetch, RUN_SETUP },
321 #endif
322                 { "init", cmd_init_db },
323                 { "init-db", cmd_init_db },
324                 { "log", cmd_log, RUN_SETUP | USE_PAGER },
325                 { "ls-files", cmd_ls_files, RUN_SETUP },
326                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
327                 { "ls-remote", cmd_ls_remote },
328                 { "mailinfo", cmd_mailinfo },
329                 { "mailsplit", cmd_mailsplit },
330                 { "merge-base", cmd_merge_base, RUN_SETUP },
331                 { "merge-file", cmd_merge_file },
332                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
333                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
334                 { "name-rev", cmd_name_rev, RUN_SETUP },
335                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
336                 { "peek-remote", cmd_ls_remote },
337                 { "pickaxe", cmd_blame, RUN_SETUP },
338                 { "prune", cmd_prune, RUN_SETUP },
339                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
340                 { "push", cmd_push, RUN_SETUP },
341                 { "read-tree", cmd_read_tree, RUN_SETUP },
342                 { "reflog", cmd_reflog, RUN_SETUP },
343                 { "repo-config", cmd_config },
344                 { "rerere", cmd_rerere, RUN_SETUP },
345                 { "reset", cmd_reset, RUN_SETUP },
346                 { "rev-list", cmd_rev_list, RUN_SETUP },
347                 { "rev-parse", cmd_rev_parse },
348                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
349                 { "rm", cmd_rm, RUN_SETUP },
350                 { "send-pack", cmd_send_pack, RUN_SETUP },
351                 { "shortlog", cmd_shortlog, RUN_SETUP | USE_PAGER },
352                 { "show-branch", cmd_show_branch, RUN_SETUP },
353                 { "show", cmd_show, RUN_SETUP | USE_PAGER },
354                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
355                 { "stripspace", cmd_stripspace },
356                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
357                 { "tag", cmd_tag, RUN_SETUP },
358                 { "tar-tree", cmd_tar_tree },
359                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
360                 { "update-index", cmd_update_index, RUN_SETUP },
361                 { "update-ref", cmd_update_ref, RUN_SETUP },
362                 { "upload-archive", cmd_upload_archive },
363                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
364                 { "version", cmd_version },
365                 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
366                 { "write-tree", cmd_write_tree, RUN_SETUP },
367                 { "verify-pack", cmd_verify_pack },
368                 { "show-ref", cmd_show_ref, RUN_SETUP },
369                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
370         };
371         int i;
372
373         /* Turn "git cmd --help" into "git help cmd" */
374         if (argc > 1 && !strcmp(argv[1], "--help")) {
375                 argv[1] = argv[0];
376                 argv[0] = cmd = "help";
377         }
378
379         for (i = 0; i < ARRAY_SIZE(commands); i++) {
380                 struct cmd_struct *p = commands+i;
381                 if (strcmp(p->cmd, cmd))
382                         continue;
383                 exit(run_command(p, argc, argv));
384         }
385 }
386
387 int main(int argc, const char **argv)
388 {
389         const char *cmd = argv[0] ? argv[0] : "git-help";
390         char *slash = strrchr(cmd, '/');
391         const char *cmd_path = NULL;
392         int done_alias = 0;
393
394         /*
395          * Take the basename of argv[0] as the command
396          * name, and the dirname as the default exec_path
397          * if we don't have anything better.
398          */
399         if (slash) {
400                 *slash++ = 0;
401                 cmd_path = cmd;
402                 cmd = slash;
403         }
404
405         /*
406          * "git-xxxx" is the same as "git xxxx", but we obviously:
407          *
408          *  - cannot take flags in between the "git" and the "xxxx".
409          *  - cannot execute it externally (since it would just do
410          *    the same thing over again)
411          *
412          * So we just directly call the internal command handler, and
413          * die if that one cannot handle it.
414          */
415         if (!prefixcmp(cmd, "git-")) {
416                 cmd += 4;
417                 argv[0] = cmd;
418                 handle_internal_command(argc, argv);
419                 die("cannot handle %s internally", cmd);
420         }
421
422         /* Look for flags.. */
423         argv++;
424         argc--;
425         handle_options(&argv, &argc, NULL);
426         if (argc > 0) {
427                 if (!prefixcmp(argv[0], "--"))
428                         argv[0] += 2;
429         } else {
430                 /* The user didn't specify a command; give them help */
431                 printf("usage: %s\n\n", git_usage_string);
432                 list_common_cmds_help();
433                 exit(1);
434         }
435         cmd = argv[0];
436
437         /*
438          * We use PATH to find git commands, but we prepend some higher
439          * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
440          * environment, and the $(gitexecdir) from the Makefile at build
441          * time.
442          */
443         setup_path(cmd_path);
444
445         while (1) {
446                 /* See if it's an internal command */
447                 handle_internal_command(argc, argv);
448
449                 /* .. then try the external ones */
450                 execv_git_cmd(argv);
451
452                 /* It could be an alias -- this works around the insanity
453                  * of overriding "git log" with "git show" by having
454                  * alias.log = show
455                  */
456                 if (done_alias || !handle_alias(&argc, &argv))
457                         break;
458                 done_alias = 1;
459         }
460
461         if (errno == ENOENT) {
462                 if (done_alias) {
463                         fprintf(stderr, "Expansion of alias '%s' failed; "
464                                 "'%s' is not a git-command\n",
465                                 cmd, argv[0]);
466                         exit(1);
467                 }
468                 help_unknown_cmd(cmd);
469         }
470
471         fprintf(stderr, "Failed to run command '%s': %s\n",
472                 cmd, strerror(errno));
473
474         return 1;
475 }