Merge branch 'db/no-git-config'
[git/git.git] / setup.c
1 #include "cache.h"
2 #include "dir.h"
3
4 static int inside_git_dir = -1;
5 static int inside_work_tree = -1;
6
7 static int sanitary_path_copy(char *dst, const char *src)
8 {
9 char *dst0;
10
11 if (has_dos_drive_prefix(src)) {
12 *dst++ = *src++;
13 *dst++ = *src++;
14 }
15 dst0 = dst;
16
17 if (is_dir_sep(*src)) {
18 *dst++ = '/';
19 while (is_dir_sep(*src))
20 src++;
21 }
22
23 for (;;) {
24 char c = *src;
25
26 /*
27 * A path component that begins with . could be
28 * special:
29 * (1) "." and ends -- ignore and terminate.
30 * (2) "./" -- ignore them, eat slash and continue.
31 * (3) ".." and ends -- strip one and terminate.
32 * (4) "../" -- strip one, eat slash and continue.
33 */
34 if (c == '.') {
35 if (!src[1]) {
36 /* (1) */
37 src++;
38 } else if (is_dir_sep(src[1])) {
39 /* (2) */
40 src += 2;
41 while (is_dir_sep(*src))
42 src++;
43 continue;
44 } else if (src[1] == '.') {
45 if (!src[2]) {
46 /* (3) */
47 src += 2;
48 goto up_one;
49 } else if (is_dir_sep(src[2])) {
50 /* (4) */
51 src += 3;
52 while (is_dir_sep(*src))
53 src++;
54 goto up_one;
55 }
56 }
57 }
58
59 /* copy up to the next '/', and eat all '/' */
60 while ((c = *src++) != '\0' && !is_dir_sep(c))
61 *dst++ = c;
62 if (is_dir_sep(c)) {
63 *dst++ = '/';
64 while (is_dir_sep(c))
65 c = *src++;
66 src--;
67 } else if (!c)
68 break;
69 continue;
70
71 up_one:
72 /*
73 * dst0..dst is prefix portion, and dst[-1] is '/';
74 * go up one level.
75 */
76 dst -= 2; /* go past trailing '/' if any */
77 if (dst < dst0)
78 return -1;
79 while (1) {
80 if (dst <= dst0)
81 break;
82 c = *dst--;
83 if (c == '/') { /* MinGW: cannot be '\\' anymore */
84 dst += 2;
85 break;
86 }
87 }
88 }
89 *dst = '\0';
90 return 0;
91 }
92
93 const char *prefix_path(const char *prefix, int len, const char *path)
94 {
95 const char *orig = path;
96 char *sanitized = xmalloc(len + strlen(path) + 1);
97 if (is_absolute_path(orig))
98 strcpy(sanitized, path);
99 else {
100 if (len)
101 memcpy(sanitized, prefix, len);
102 strcpy(sanitized + len, path);
103 }
104 if (sanitary_path_copy(sanitized, sanitized))
105 goto error_out;
106 if (is_absolute_path(orig)) {
107 const char *work_tree = get_git_work_tree();
108 size_t len = strlen(work_tree);
109 size_t total = strlen(sanitized) + 1;
110 if (strncmp(sanitized, work_tree, len) ||
111 (sanitized[len] != '\0' && sanitized[len] != '/')) {
112 error_out:
113 error("'%s' is outside repository", orig);
114 free(sanitized);
115 return NULL;
116 }
117 if (sanitized[len] == '/')
118 len++;
119 memmove(sanitized, sanitized + len, total - len);
120 }
121 return sanitized;
122 }
123
124 /*
125 * Unlike prefix_path, this should be used if the named file does
126 * not have to interact with index entry; i.e. name of a random file
127 * on the filesystem.
128 */
129 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
130 {
131 static char path[PATH_MAX];
132 #ifndef __MINGW32__
133 if (!pfx || !*pfx || is_absolute_path(arg))
134 return arg;
135 memcpy(path, pfx, pfx_len);
136 strcpy(path + pfx_len, arg);
137 #else
138 char *p;
139 /* don't add prefix to absolute paths, but still replace '\' by '/' */
140 if (is_absolute_path(arg))
141 pfx_len = 0;
142 else
143 memcpy(path, pfx, pfx_len);
144 strcpy(path + pfx_len, arg);
145 for (p = path + pfx_len; *p; p++)
146 if (*p == '\\')
147 *p = '/';
148 #endif
149 return path;
150 }
151
152 /*
153 * Verify a filename that we got as an argument for a pathspec
154 * entry. Note that a filename that begins with "-" never verifies
155 * as true, because even if such a filename were to exist, we want
156 * it to be preceded by the "--" marker (or we want the user to
157 * use a format like "./-filename")
158 */
159 void verify_filename(const char *prefix, const char *arg)
160 {
161 const char *name;
162 struct stat st;
163
164 if (*arg == '-')
165 die("bad flag '%s' used after filename", arg);
166 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
167 if (!lstat(name, &st))
168 return;
169 if (errno == ENOENT)
170 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
171 "Use '--' to separate paths from revisions", arg);
172 die("'%s': %s", arg, strerror(errno));
173 }
174
175 /*
176 * Opposite of the above: the command line did not have -- marker
177 * and we parsed the arg as a refname. It should not be interpretable
178 * as a filename.
179 */
180 void verify_non_filename(const char *prefix, const char *arg)
181 {
182 const char *name;
183 struct stat st;
184
185 if (!is_inside_work_tree() || is_inside_git_dir())
186 return;
187 if (*arg == '-')
188 return; /* flag */
189 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
190 if (!lstat(name, &st))
191 die("ambiguous argument '%s': both revision and filename\n"
192 "Use '--' to separate filenames from revisions", arg);
193 if (errno != ENOENT && errno != ENOTDIR)
194 die("'%s': %s", arg, strerror(errno));
195 }
196
197 const char **get_pathspec(const char *prefix, const char **pathspec)
198 {
199 const char *entry = *pathspec;
200 const char **src, **dst;
201 int prefixlen;
202
203 if (!prefix && !entry)
204 return NULL;
205
206 if (!entry) {
207 static const char *spec[2];
208 spec[0] = prefix;
209 spec[1] = NULL;
210 return spec;
211 }
212
213 /* Otherwise we have to re-write the entries.. */
214 src = pathspec;
215 dst = pathspec;
216 prefixlen = prefix ? strlen(prefix) : 0;
217 while (*src) {
218 const char *p = prefix_path(prefix, prefixlen, *src);
219 if (p)
220 *(dst++) = p;
221 else
222 exit(128); /* error message already given */
223 src++;
224 }
225 *dst = NULL;
226 if (!*pathspec)
227 return NULL;
228 return pathspec;
229 }
230
231 /*
232 * Test if it looks like we're at a git directory.
233 * We want to see:
234 *
235 * - either an objects/ directory _or_ the proper
236 * GIT_OBJECT_DIRECTORY environment variable
237 * - a refs/ directory
238 * - either a HEAD symlink or a HEAD file that is formatted as
239 * a proper "ref:", or a regular file HEAD that has a properly
240 * formatted sha1 object name.
241 */
242 static int is_git_directory(const char *suspect)
243 {
244 char path[PATH_MAX];
245 size_t len = strlen(suspect);
246
247 strcpy(path, suspect);
248 if (getenv(DB_ENVIRONMENT)) {
249 if (access(getenv(DB_ENVIRONMENT), X_OK))
250 return 0;
251 }
252 else {
253 strcpy(path + len, "/objects");
254 if (access(path, X_OK))
255 return 0;
256 }
257
258 strcpy(path + len, "/refs");
259 if (access(path, X_OK))
260 return 0;
261
262 strcpy(path + len, "/HEAD");
263 if (validate_headref(path))
264 return 0;
265
266 return 1;
267 }
268
269 int is_inside_git_dir(void)
270 {
271 if (inside_git_dir < 0)
272 inside_git_dir = is_inside_dir(get_git_dir());
273 return inside_git_dir;
274 }
275
276 int is_inside_work_tree(void)
277 {
278 if (inside_work_tree < 0)
279 inside_work_tree = is_inside_dir(get_git_work_tree());
280 return inside_work_tree;
281 }
282
283 /*
284 * set_work_tree() is only ever called if you set GIT_DIR explicitely.
285 * The old behaviour (which we retain here) is to set the work tree root
286 * to the cwd, unless overridden by the config, the command line, or
287 * GIT_WORK_TREE.
288 */
289 static const char *set_work_tree(const char *dir)
290 {
291 char buffer[PATH_MAX + 1];
292
293 if (!getcwd(buffer, sizeof(buffer)))
294 die ("Could not get the current working directory");
295 git_work_tree_cfg = xstrdup(buffer);
296 inside_work_tree = 1;
297
298 return NULL;
299 }
300
301 void setup_work_tree(void)
302 {
303 const char *work_tree, *git_dir;
304 static int initialized = 0;
305
306 if (initialized)
307 return;
308 work_tree = get_git_work_tree();
309 git_dir = get_git_dir();
310 if (!is_absolute_path(git_dir))
311 git_dir = make_absolute_path(git_dir);
312 if (!work_tree || chdir(work_tree))
313 die("This operation must be run in a work tree");
314 set_git_dir(make_relative_path(git_dir, work_tree));
315 initialized = 1;
316 }
317
318 static int check_repository_format_gently(int *nongit_ok)
319 {
320 git_config(check_repository_format_version, NULL);
321 if (GIT_REPO_VERSION < repository_format_version) {
322 if (!nongit_ok)
323 die ("Expected git repo version <= %d, found %d",
324 GIT_REPO_VERSION, repository_format_version);
325 warning("Expected git repo version <= %d, found %d",
326 GIT_REPO_VERSION, repository_format_version);
327 warning("Please upgrade Git");
328 *nongit_ok = -1;
329 return -1;
330 }
331 return 0;
332 }
333
334 /*
335 * Try to read the location of the git directory from the .git file,
336 * return path to git directory if found.
337 */
338 const char *read_gitfile_gently(const char *path)
339 {
340 char *buf;
341 struct stat st;
342 int fd;
343 size_t len;
344
345 if (stat(path, &st))
346 return NULL;
347 if (!S_ISREG(st.st_mode))
348 return NULL;
349 fd = open(path, O_RDONLY);
350 if (fd < 0)
351 die("Error opening %s: %s", path, strerror(errno));
352 buf = xmalloc(st.st_size + 1);
353 len = read_in_full(fd, buf, st.st_size);
354 close(fd);
355 if (len != st.st_size)
356 die("Error reading %s", path);
357 buf[len] = '\0';
358 if (prefixcmp(buf, "gitdir: "))
359 die("Invalid gitfile format: %s", path);
360 while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
361 len--;
362 if (len < 9)
363 die("No path in gitfile: %s", path);
364 buf[len] = '\0';
365 if (!is_git_directory(buf + 8))
366 die("Not a git repository: %s", buf + 8);
367 path = make_absolute_path(buf + 8);
368 free(buf);
369 return path;
370 }
371
372 /*
373 * We cannot decide in this function whether we are in the work tree or
374 * not, since the config can only be read _after_ this function was called.
375 */
376 const char *setup_git_directory_gently(int *nongit_ok)
377 {
378 const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
379 static char cwd[PATH_MAX+1];
380 const char *gitdirenv;
381 const char *gitfile_dir;
382 int len, offset;
383 int minoffset = 0;
384
385 /*
386 * Let's assume that we are in a git repository.
387 * If it turns out later that we are somewhere else, the value will be
388 * updated accordingly.
389 */
390 if (nongit_ok)
391 *nongit_ok = 0;
392
393 /*
394 * If GIT_DIR is set explicitly, we're not going
395 * to do any discovery, but we still do repository
396 * validation.
397 */
398 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
399 if (gitdirenv) {
400 if (PATH_MAX - 40 < strlen(gitdirenv))
401 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
402 if (is_git_directory(gitdirenv)) {
403 static char buffer[1024 + 1];
404 const char *retval;
405
406 if (!work_tree_env) {
407 retval = set_work_tree(gitdirenv);
408 /* config may override worktree */
409 if (check_repository_format_gently(nongit_ok))
410 return NULL;
411 return retval;
412 }
413 if (check_repository_format_gently(nongit_ok))
414 return NULL;
415 retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
416 get_git_work_tree());
417 if (!retval || !*retval)
418 return NULL;
419 set_git_dir(make_absolute_path(gitdirenv));
420 if (chdir(work_tree_env) < 0)
421 die ("Could not chdir to %s", work_tree_env);
422 strcat(buffer, "/");
423 return retval;
424 }
425 if (nongit_ok) {
426 *nongit_ok = 1;
427 return NULL;
428 }
429 die("Not a git repository: '%s'", gitdirenv);
430 }
431
432 if (!getcwd(cwd, sizeof(cwd)-1))
433 die("Unable to read current working directory");
434 if (has_dos_drive_prefix(cwd))
435 minoffset = 2;
436
437 /*
438 * Test in the following order (relative to the cwd):
439 * - .git (file containing "gitdir: <path>")
440 * - .git/
441 * - ./ (bare)
442 * - ../.git
443 * - ../.git/
444 * - ../ (bare)
445 * - ../../.git/
446 * etc.
447 */
448 offset = len = strlen(cwd);
449 for (;;) {
450 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
451 if (gitfile_dir) {
452 if (set_git_dir(gitfile_dir))
453 die("Repository setup failed");
454 break;
455 }
456 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
457 break;
458 if (is_git_directory(".")) {
459 inside_git_dir = 1;
460 if (!work_tree_env)
461 inside_work_tree = 0;
462 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
463 check_repository_format_gently(nongit_ok);
464 return NULL;
465 }
466 chdir("..");
467 do {
468 if (offset <= minoffset) {
469 if (nongit_ok) {
470 if (chdir(cwd))
471 die("Cannot come back to cwd");
472 *nongit_ok = 1;
473 return NULL;
474 }
475 die("Not a git repository");
476 }
477 } while (offset > minoffset && cwd[--offset] != '/');
478 }
479
480 inside_git_dir = 0;
481 if (!work_tree_env)
482 inside_work_tree = 1;
483 git_work_tree_cfg = xstrndup(cwd, offset);
484 if (check_repository_format_gently(nongit_ok))
485 return NULL;
486 if (offset == len)
487 return NULL;
488
489 /* Make "offset" point to past the '/', and add a '/' at the end */
490 offset++;
491 cwd[len++] = '/';
492 cwd[len] = 0;
493 return cwd + offset;
494 }
495
496 int git_config_perm(const char *var, const char *value)
497 {
498 int i;
499 char *endptr;
500
501 if (value == NULL)
502 return PERM_GROUP;
503
504 if (!strcmp(value, "umask"))
505 return PERM_UMASK;
506 if (!strcmp(value, "group"))
507 return PERM_GROUP;
508 if (!strcmp(value, "all") ||
509 !strcmp(value, "world") ||
510 !strcmp(value, "everybody"))
511 return PERM_EVERYBODY;
512
513 /* Parse octal numbers */
514 i = strtol(value, &endptr, 8);
515
516 /* If not an octal number, maybe true/false? */
517 if (*endptr != 0)
518 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
519
520 /*
521 * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
522 * a chmod value.
523 */
524 switch (i) {
525 case PERM_UMASK: /* 0 */
526 return PERM_UMASK;
527 case OLD_PERM_GROUP: /* 1 */
528 return PERM_GROUP;
529 case OLD_PERM_EVERYBODY: /* 2 */
530 return PERM_EVERYBODY;
531 }
532
533 /* A filemode value was given: 0xxx */
534
535 if ((i & 0600) != 0600)
536 die("Problem with core.sharedRepository filemode value "
537 "(0%.3o).\nThe owner of files must always have "
538 "read and write permissions.", i);
539
540 /*
541 * Mask filemode value. Others can not get write permission.
542 * x flags for directories are handled separately.
543 */
544 return i & 0666;
545 }
546
547 int check_repository_format_version(const char *var, const char *value, void *cb)
548 {
549 if (strcmp(var, "core.repositoryformatversion") == 0)
550 repository_format_version = git_config_int(var, value);
551 else if (strcmp(var, "core.sharedrepository") == 0)
552 shared_repository = git_config_perm(var, value);
553 else if (strcmp(var, "core.bare") == 0) {
554 is_bare_repository_cfg = git_config_bool(var, value);
555 if (is_bare_repository_cfg == 1)
556 inside_work_tree = -1;
557 } else if (strcmp(var, "core.worktree") == 0) {
558 if (!value)
559 return config_error_nonbool(var);
560 free(git_work_tree_cfg);
561 git_work_tree_cfg = xstrdup(value);
562 inside_work_tree = -1;
563 }
564 return 0;
565 }
566
567 int check_repository_format(void)
568 {
569 return check_repository_format_gently(NULL);
570 }
571
572 const char *setup_git_directory(void)
573 {
574 const char *retval = setup_git_directory_gently(NULL);
575
576 /* If the work tree is not the default one, recompute prefix */
577 if (inside_work_tree < 0) {
578 static char buffer[PATH_MAX + 1];
579 char *rel;
580 if (retval && chdir(retval))
581 die ("Could not jump back into original cwd");
582 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
583 return rel && *rel ? strcat(rel, "/") : NULL;
584 }
585
586 return retval;
587 }