aboutsummaryrefslogtreecommitdiff
path: root/git.c
blob: efed91c4f47bea97db52e931ad6652e2eaac152e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
#include "builtin.h"
#include "exec_cmd.h"
#include "cache.h"
#include "quote.h"

const char git_usage_string[] =
	"git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate|--no-pager] [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE] [--help] COMMAND [ARGS]";

static void prepend_to_path(const char *dir, int len)
{
	const char *old_path = getenv("PATH");
	char *path;
	int path_len = len;

	if (!old_path)
		old_path = "/usr/local/bin:/usr/bin:/bin";

	path_len = len + strlen(old_path) + 1;

	path = xmalloc(path_len + 1);

	memcpy(path, dir, len);
	path[len] = ':';
	memcpy(path + len + 1, old_path, path_len - len);

	setenv("PATH", path, 1);

	free(path);
}

static int handle_options(const char*** argv, int* argc, int* envchanged)
{
	int handled = 0;

	while (*argc > 0) {
		const char *cmd = (*argv)[0];
		if (cmd[0] != '-')
			break;

		/*
		 * For legacy reasons, the "version" and "help"
		 * commands can be written with "--" prepended
		 * to make them look like flags.
		 */
		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
			break;

		/*
		 * Check remaining flags.
		 */
		if (!prefixcmp(cmd, "--exec-path")) {
			cmd += 11;
			if (*cmd == '=')
				git_set_exec_path(cmd + 1);
			else {
				puts(git_exec_path());
				exit(0);
			}
		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
			setup_pager();
		} else if (!strcmp(cmd, "--no-pager")) {
			setenv("GIT_PAGER", "cat", 1);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--git-dir")) {
			if (*argc < 2) {
				fprintf(stderr, "No directory given for --git-dir.\n" );
				usage(git_usage_string);
			}
			setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
			if (envchanged)
				*envchanged = 1;
			(*argv)++;
			(*argc)--;
			handled++;
		} else if (!prefixcmp(cmd, "--git-dir=")) {
			setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--work-tree")) {
			if (*argc < 2) {
				fprintf(stderr, "No directory given for --work-tree.\n" );
				usage(git_usage_string);
			}
			setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
			if (envchanged)
				*envchanged = 1;
			(*argv)++;
			(*argc)--;
		} else if (!prefixcmp(cmd, "--work-tree=")) {
			setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--bare")) {
			static char git_dir[PATH_MAX+1];
			is_bare_repository_cfg = 1;
			setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
			if (envchanged)
				*envchanged = 1;
		} else {
			fprintf(stderr, "Unknown option: %s\n", cmd);
			usage(git_usage_string);
		}

		(*argv)++;
		(*argc)--;
		handled++;
	}
	return handled;
}

static const char *alias_command;
static char *alias_string;

static int git_alias_config(const char *var, const char *value)
{
	if (!prefixcmp(var, "alias.") && !strcmp(var + 6, alias_command)) {
		alias_string = xstrdup(value);
	}
	return 0;
}

static int split_cmdline(char *cmdline, const char ***argv)
{
	int src, dst, count = 0, size = 16;
	char quoted = 0;

	*argv = xmalloc(sizeof(char*) * size);

	/* split alias_string */
	(*argv)[count++] = cmdline;
	for (src = dst = 0; cmdline[src];) {
		char c = cmdline[src];
		if (!quoted && isspace(c)) {
			cmdline[dst++] = 0;
			while (cmdline[++src]
					&& isspace(cmdline[src]))
				; /* skip */
			if (count >= size) {
				size += 16;
				*argv = xrealloc(*argv, sizeof(char*) * size);
			}
			(*argv)[count++] = cmdline + dst;
		} else if(!quoted && (c == '\'' || c == '"')) {
			quoted = c;
			src++;
		} else if (c == quoted) {
			quoted = 0;
			src++;
		} else {
			if (c == '\\' && quoted != '\'') {
				src++;
				c = cmdline[src];
				if (!c) {
					free(*argv);
					*argv = NULL;
					return error("cmdline ends with \\");
				}
			}
			cmdline[dst++] = c;
			src++;
		}
	}

	cmdline[dst] = 0;

	if (quoted) {
		free(*argv);
		*argv = NULL;
		return error("unclosed quote");
	}

	return count;
}

static int handle_alias(int *argcp, const char ***argv)
{
	int nongit = 0, envchanged = 0, ret = 0, saved_errno = errno;
	const char *subdir;
	int count, option_count;
	const char** new_argv;

	subdir = setup_git_directory_gently(&nongit);

	alias_command = (*argv)[0];
	git_config(git_alias_config);
	if (alias_string) {
		if (alias_string[0] == '!') {
			if (*argcp > 1) {
				struct strbuf buf;

				strbuf_init(&buf, PATH_MAX);
				strbuf_addstr(&buf, alias_string);
				sq_quote_argv(&buf, (*argv) + 1, *argcp - 1, PATH_MAX);
				free(alias_string);
				alias_string = buf.buf;
			}
			trace_printf("trace: alias to shell cmd: %s => %s\n",
				     alias_command, alias_string + 1);
			ret = system(alias_string + 1);
			if (ret >= 0 && WIFEXITED(ret) &&
			    WEXITSTATUS(ret) != 127)
				exit(WEXITSTATUS(ret));
			die("Failed to run '%s' when expanding alias '%s'\n",
			    alias_string + 1, alias_command);
		}
		count = split_cmdline(alias_string, &new_argv);
		option_count = handle_options(&new_argv, &count, &envchanged);
		if (envchanged)
			die("alias '%s' changes environment variables\n"
				 "You can use '!git' in the alias to do this.",
				 alias_command);
		memmove(new_argv - option_count, new_argv,
				count * sizeof(char *));
		new_argv -= option_count;

		if (count < 1)
			die("empty alias for %s", alias_command);

		if (!strcmp(alias_command, new_argv[0]))
			die("recursive alias: %s", alias_command);

		trace_argv_printf(new_argv, count,
				  "trace: alias expansion: %s =>",
				  alias_command);

		new_argv = xrealloc(new_argv, sizeof(char*) *
				    (count + *argcp + 1));
		/* insert after command name */
		memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
		new_argv[count+*argcp] = NULL;

		*argv = new_argv;
		*argcp += count - 1;

		ret = 1;
	}

	if (subdir)
		chdir(subdir);

	errno = saved_errno;

	return ret;
}

const char git_version_string[] = GIT_VERSION;

#define RUN_SETUP	(1<<0)
#define USE_PAGER	(1<<1)
/*
 * require working tree to be present -- anything uses this needs
 * RUN_SETUP for reading from the configuration file.
 */
#define NEED_WORK_TREE	(1<<2)

struct cmd_struct {
	const char *cmd;
	int (*fn)(int, const char **, const char *);
	int option;
};

static int run_command(struct cmd_struct *p, int argc, const char **argv)
{
	int status;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = setup_git_directory();
	if (p->option & USE_PAGER)
		setup_pager();
	if (p->option & NEED_WORK_TREE) {
		const char *work_tree = get_git_work_tree();
		const char *git_dir = get_git_dir();
		if (!is_absolute_path(git_dir))
			set_git_dir(make_absolute_path(git_dir));
		if (!work_tree || chdir(work_tree))
			die("%s must be run in a work tree", p->cmd);
	}
	trace_argv_printf(argv, argc, "trace: built-in: git");

	status = p->fn(argc, argv, prefix);
	if (status)
		return status;

	/* Somebody closed stdout? */
	if (fstat(fileno(stdout), &st))
		return 0;
	/* Ignore write errors for pipes and sockets.. */
	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
		return 0;

	/* Check for ENOSPC and EIO errors.. */
	if (fflush(stdout))
		die("write failure on standard output: %s", strerror(errno));
	if (ferror(stdout))
		die("unknown write failure on standard output");
	if (fclose(stdout))
		die("close failed on standard output: %s", strerror(errno));
	return 0;
}

static void handle_internal_command(int argc, const char **argv)
{
	const char *cmd = argv[0];
	static struct cmd_struct commands[] = {
		{ "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
		{ "annotate", cmd_annotate, RUN_SETUP },
		{ "apply", cmd_apply },
		{ "archive", cmd_archive },
		{ "blame", cmd_blame, RUN_SETUP },
		{ "branch", cmd_branch, RUN_SETUP },
		{ "bundle", cmd_bundle },
		{ "cat-file", cmd_cat_file, RUN_SETUP },
		{ "checkout-index", cmd_checkout_index,
			RUN_SETUP | NEED_WORK_TREE},
		{ "check-ref-format", cmd_check_ref_format },
		{ "check-attr", cmd_check_attr, RUN_SETUP | NEED_WORK_TREE },
		{ "cherry", cmd_cherry, RUN_SETUP },
		{ "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
		{ "commit-tree", cmd_commit_tree, RUN_SETUP },
		{ "config", cmd_config },
		{ "count-objects", cmd_count_objects, RUN_SETUP },
		{ "describe", cmd_describe, RUN_SETUP },
		{ "diff", cmd_diff },
		{ "diff-files", cmd_diff_files },
		{ "diff-index", cmd_diff_index, RUN_SETUP },
		{ "diff-tree", cmd_diff_tree, RUN_SETUP },
		{ "fetch", cmd_fetch, RUN_SETUP },
		{ "fetch-pack", cmd_fetch_pack, RUN_SETUP },
		{ "fetch--tool", cmd_fetch__tool, RUN_SETUP },
		{ "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
		{ "for-each-ref", cmd_for_each_ref, RUN_SETUP },
		{ "format-patch", cmd_format_patch, RUN_SETUP },
		{ "fsck", cmd_fsck, RUN_SETUP },
		{ "fsck-objects", cmd_fsck, RUN_SETUP },
		{ "gc", cmd_gc, RUN_SETUP },
		{ "get-tar-commit-id", cmd_get_tar_commit_id },
		{ "grep", cmd_grep, RUN_SETUP | USE_PAGER },
		{ "help", cmd_help },
#ifndef NO_CURL
		{ "http-fetch", cmd_http_fetch, RUN_SETUP },
#endif
		{ "init", cmd_init_db },
		{ "init-db", cmd_init_db },
		{ "log", cmd_log, RUN_SETUP | USE_PAGER },
		{ "ls-files", cmd_ls_files, RUN_SETUP },
		{ "ls-tree", cmd_ls_tree, RUN_SETUP },
		{ "mailinfo", cmd_mailinfo },
		{ "mailsplit", cmd_mailsplit },
		{ "merge-base", cmd_merge_base, RUN_SETUP },
		{ "merge-file", cmd_merge_file },
		{ "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
		{ "name-rev", cmd_name_rev, RUN_SETUP },
		{ "pack-objects", cmd_pack_objects, RUN_SETUP },
		{ "pickaxe", cmd_blame, RUN_SETUP },
		{ "prune", cmd_prune, RUN_SETUP },
		{ "prune-packed", cmd_prune_packed, RUN_SETUP },
		{ "push", cmd_push, RUN_SETUP },
		{ "read-tree", cmd_read_tree, RUN_SETUP },
		{ "reflog", cmd_reflog, RUN_SETUP },
		{ "repo-config", cmd_config },
		{ "rerere", cmd_rerere, RUN_SETUP },
		{ "reset", cmd_reset, RUN_SETUP },
		{ "rev-list", cmd_rev_list, RUN_SETUP },
		{ "rev-parse", cmd_rev_parse, RUN_SETUP },
		{ "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
		{ "rm", cmd_rm, RUN_SETUP | NEED_WORK_TREE },
		{ "runstatus", cmd_runstatus, RUN_SETUP | NEED_WORK_TREE },
		{ "shortlog", cmd_shortlog, RUN_SETUP | USE_PAGER },
		{ "show-branch", cmd_show_branch, RUN_SETUP },
		{ "show", cmd_show, RUN_SETUP | USE_PAGER },
		{ "stripspace", cmd_stripspace },
		{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
		{ "tag", cmd_tag, RUN_SETUP },
		{ "tar-tree", cmd_tar_tree },
		{ "unpack-objects", cmd_unpack_objects, RUN_SETUP },
		{ "update-index", cmd_update_index, RUN_SETUP },
		{ "update-ref", cmd_update_ref, RUN_SETUP },
		{ "upload-archive", cmd_upload_archive },
		{ "verify-tag", cmd_verify_tag, RUN_SETUP },
		{ "version", cmd_version },
		{ "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
		{ "write-tree", cmd_write_tree, RUN_SETUP },
		{ "verify-pack", cmd_verify_pack },
		{ "show-ref", cmd_show_ref, RUN_SETUP },
		{ "pack-refs", cmd_pack_refs, RUN_SETUP },
	};
	int i;

	/* Turn "git cmd --help" into "git help cmd" */
	if (argc > 1 && !strcmp(argv[1], "--help")) {
		argv[1] = argv[0];
		argv[0] = cmd = "help";
	}

	for (i = 0; i < ARRAY_SIZE(commands); i++) {
		struct cmd_struct *p = commands+i;
		if (strcmp(p->cmd, cmd))
			continue;
		exit(run_command(p, argc, argv));
	}
}

int main(int argc, const char **argv)
{
	const char *cmd = argv[0] ? argv[0] : "git-help";
	char *slash = strrchr(cmd, '/');
	const char *exec_path = NULL;
	int done_alias = 0;

	/*
	 * Take the basename of argv[0] as the command
	 * name, and the dirname as the default exec_path
	 * if we don't have anything better.
	 */
	if (slash) {
		*slash++ = 0;
		if (*cmd == '/')
			exec_path = cmd;
		else
			exec_path = xstrdup(make_absolute_path(cmd));
		cmd = slash;
	}

	/*
	 * "git-xxxx" is the same as "git xxxx", but we obviously:
	 *
	 *  - cannot take flags in between the "git" and the "xxxx".
	 *  - cannot execute it externally (since it would just do
	 *    the same thing over again)
	 *
	 * So we just directly call the internal command handler, and
	 * die if that one cannot handle it.
	 */
	if (!prefixcmp(cmd, "git-")) {
		cmd += 4;
		argv[0] = cmd;
		handle_internal_command(argc, argv);
		die("cannot handle %s internally", cmd);
	}

	/* Look for flags.. */
	argv++;
	argc--;
	handle_options(&argv, &argc, NULL);
	if (argc > 0) {
		if (!prefixcmp(argv[0], "--"))
			argv[0] += 2;
	} else {
		/* The user didn't specify a command; give them help */
		printf("usage: %s\n\n", git_usage_string);
		list_common_cmds_help();
		exit(1);
	}
	cmd = argv[0];

	/*
	 * We execute external git command via execv_git_cmd(),
	 * which looks at "--exec-path" option, GIT_EXEC_PATH
	 * environment, and $(gitexecdir) in Makefile while built,
	 * in this order.  For scripted commands, we prepend
	 * the value of the exec_path variable to the PATH.
	 */
	if (exec_path)
		prepend_to_path(exec_path, strlen(exec_path));
	exec_path = git_exec_path();
	prepend_to_path(exec_path, strlen(exec_path));

	while (1) {
		/* See if it's an internal command */
		handle_internal_command(argc, argv);

		/* .. then try the external ones */
		execv_git_cmd(argv);

		/* It could be an alias -- this works around the insanity
		 * of overriding "git log" with "git show" by having
		 * alias.log = show
		 */
		if (done_alias || !handle_alias(&argc, &argv))
			break;
		done_alias = 1;
	}

	if (errno == ENOENT) {
		if (done_alias) {
			fprintf(stderr, "Expansion of alias '%s' failed; "
				"'%s' is not a git-command\n",
				cmd, argv[0]);
			exit(1);
		}
		help_unknown_cmd(cmd);
	}

	fprintf(stderr, "Failed to run command '%s': %s\n",
		cmd, strerror(errno));

	return 1;
}