streaming: a new API to read from the object store
[git/jnareb-git.git] / setup.c
blobb6e6b5ae272b3ecae7dfa2cb446aef97e826884a
1 #include "cache.h"
2 #include "dir.h"
4 static int inside_git_dir = -1;
5 static int inside_work_tree = -1;
7 char *prefix_path(const char *prefix, int len, const char *path)
9 const char *orig = path;
10 char *sanitized;
11 if (is_absolute_path(orig)) {
12 const char *temp = real_path(path);
13 sanitized = xmalloc(len + strlen(temp) + 1);
14 strcpy(sanitized, temp);
15 } else {
16 sanitized = xmalloc(len + strlen(path) + 1);
17 if (len)
18 memcpy(sanitized, prefix, len);
19 strcpy(sanitized + len, path);
21 if (normalize_path_copy(sanitized, sanitized))
22 goto error_out;
23 if (is_absolute_path(orig)) {
24 size_t root_len, len, total;
25 const char *work_tree = get_git_work_tree();
26 if (!work_tree)
27 goto error_out;
28 len = strlen(work_tree);
29 root_len = offset_1st_component(work_tree);
30 total = strlen(sanitized) + 1;
31 if (strncmp(sanitized, work_tree, len) ||
32 (len > root_len && sanitized[len] != '\0' && sanitized[len] != '/')) {
33 error_out:
34 die("'%s' is outside repository", orig);
36 if (sanitized[len] == '/')
37 len++;
38 memmove(sanitized, sanitized + len, total - len);
40 return sanitized;
44 * Unlike prefix_path, this should be used if the named file does
45 * not have to interact with index entry; i.e. name of a random file
46 * on the filesystem.
48 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
50 static char path[PATH_MAX];
51 #ifndef WIN32
52 if (!pfx_len || is_absolute_path(arg))
53 return arg;
54 memcpy(path, pfx, pfx_len);
55 strcpy(path + pfx_len, arg);
56 #else
57 char *p;
58 /* don't add prefix to absolute paths, but still replace '\' by '/' */
59 if (is_absolute_path(arg))
60 pfx_len = 0;
61 else if (pfx_len)
62 memcpy(path, pfx, pfx_len);
63 strcpy(path + pfx_len, arg);
64 for (p = path + pfx_len; *p; p++)
65 if (*p == '\\')
66 *p = '/';
67 #endif
68 return path;
71 int check_filename(const char *prefix, const char *arg)
73 const char *name;
74 struct stat st;
76 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
77 if (!lstat(name, &st))
78 return 1; /* file exists */
79 if (errno == ENOENT || errno == ENOTDIR)
80 return 0; /* file does not exist */
81 die_errno("failed to stat '%s'", arg);
84 static void NORETURN die_verify_filename(const char *prefix, const char *arg)
86 unsigned char sha1[20];
87 unsigned mode;
88 /* try a detailed diagnostic ... */
89 get_sha1_with_mode_1(arg, sha1, &mode, 0, prefix);
90 /* ... or fall back the most general message. */
91 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
92 "Use '--' to separate paths from revisions", arg);
97 * Verify a filename that we got as an argument for a pathspec
98 * entry. Note that a filename that begins with "-" never verifies
99 * as true, because even if such a filename were to exist, we want
100 * it to be preceded by the "--" marker (or we want the user to
101 * use a format like "./-filename")
103 void verify_filename(const char *prefix, const char *arg)
105 if (*arg == '-')
106 die("bad flag '%s' used after filename", arg);
107 if (check_filename(prefix, arg))
108 return;
109 die_verify_filename(prefix, arg);
113 * Opposite of the above: the command line did not have -- marker
114 * and we parsed the arg as a refname. It should not be interpretable
115 * as a filename.
117 void verify_non_filename(const char *prefix, const char *arg)
119 if (!is_inside_work_tree() || is_inside_git_dir())
120 return;
121 if (*arg == '-')
122 return; /* flag */
123 if (!check_filename(prefix, arg))
124 return;
125 die("ambiguous argument '%s': both revision and filename\n"
126 "Use '--' to separate filenames from revisions", arg);
129 const char **get_pathspec(const char *prefix, const char **pathspec)
131 const char *entry = *pathspec;
132 const char **src, **dst;
133 int prefixlen;
135 if (!prefix && !entry)
136 return NULL;
138 if (!entry) {
139 static const char *spec[2];
140 spec[0] = prefix;
141 spec[1] = NULL;
142 return spec;
145 /* Otherwise we have to re-write the entries.. */
146 src = pathspec;
147 dst = pathspec;
148 prefixlen = prefix ? strlen(prefix) : 0;
149 while (*src) {
150 const char *p = prefix_path(prefix, prefixlen, *src);
151 *(dst++) = p;
152 src++;
154 *dst = NULL;
155 if (!*pathspec)
156 return NULL;
157 return pathspec;
161 * Test if it looks like we're at a git directory.
162 * We want to see:
164 * - either an objects/ directory _or_ the proper
165 * GIT_OBJECT_DIRECTORY environment variable
166 * - a refs/ directory
167 * - either a HEAD symlink or a HEAD file that is formatted as
168 * a proper "ref:", or a regular file HEAD that has a properly
169 * formatted sha1 object name.
171 static int is_git_directory(const char *suspect)
173 char path[PATH_MAX];
174 size_t len = strlen(suspect);
176 if (PATH_MAX <= len + strlen("/objects"))
177 die("Too long path: %.*s", 60, suspect);
178 strcpy(path, suspect);
179 if (getenv(DB_ENVIRONMENT)) {
180 if (access(getenv(DB_ENVIRONMENT), X_OK))
181 return 0;
183 else {
184 strcpy(path + len, "/objects");
185 if (access(path, X_OK))
186 return 0;
189 strcpy(path + len, "/refs");
190 if (access(path, X_OK))
191 return 0;
193 strcpy(path + len, "/HEAD");
194 if (validate_headref(path))
195 return 0;
197 return 1;
200 int is_inside_git_dir(void)
202 if (inside_git_dir < 0)
203 inside_git_dir = is_inside_dir(get_git_dir());
204 return inside_git_dir;
207 int is_inside_work_tree(void)
209 if (inside_work_tree < 0)
210 inside_work_tree = is_inside_dir(get_git_work_tree());
211 return inside_work_tree;
214 void setup_work_tree(void)
216 const char *work_tree, *git_dir;
217 static int initialized = 0;
219 if (initialized)
220 return;
221 work_tree = get_git_work_tree();
222 git_dir = get_git_dir();
223 if (!is_absolute_path(git_dir))
224 git_dir = real_path(get_git_dir());
225 if (!work_tree || chdir(work_tree))
226 die("This operation must be run in a work tree");
229 * Make sure subsequent git processes find correct worktree
230 * if $GIT_WORK_TREE is set relative
232 if (getenv(GIT_WORK_TREE_ENVIRONMENT))
233 setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
235 set_git_dir(relative_path(git_dir, work_tree));
236 initialized = 1;
239 static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
241 char repo_config[PATH_MAX+1];
244 * git_config() can't be used here because it calls git_pathdup()
245 * to get $GIT_CONFIG/config. That call will make setup_git_env()
246 * set git_dir to ".git".
248 * We are in gitdir setup, no git dir has been found useable yet.
249 * Use a gentler version of git_config() to check if this repo
250 * is a good one.
252 snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
253 git_config_early(check_repository_format_version, NULL, repo_config);
254 if (GIT_REPO_VERSION < repository_format_version) {
255 if (!nongit_ok)
256 die ("Expected git repo version <= %d, found %d",
257 GIT_REPO_VERSION, repository_format_version);
258 warning("Expected git repo version <= %d, found %d",
259 GIT_REPO_VERSION, repository_format_version);
260 warning("Please upgrade Git");
261 *nongit_ok = -1;
262 return -1;
264 return 0;
268 * Try to read the location of the git directory from the .git file,
269 * return path to git directory if found.
271 const char *read_gitfile_gently(const char *path)
273 char *buf;
274 char *dir;
275 const char *slash;
276 struct stat st;
277 int fd;
278 size_t len;
280 if (stat(path, &st))
281 return NULL;
282 if (!S_ISREG(st.st_mode))
283 return NULL;
284 fd = open(path, O_RDONLY);
285 if (fd < 0)
286 die_errno("Error opening '%s'", path);
287 buf = xmalloc(st.st_size + 1);
288 len = read_in_full(fd, buf, st.st_size);
289 close(fd);
290 if (len != st.st_size)
291 die("Error reading %s", path);
292 buf[len] = '\0';
293 if (prefixcmp(buf, "gitdir: "))
294 die("Invalid gitfile format: %s", path);
295 while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
296 len--;
297 if (len < 9)
298 die("No path in gitfile: %s", path);
299 buf[len] = '\0';
300 dir = buf + 8;
302 if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
303 size_t pathlen = slash+1 - path;
304 size_t dirlen = pathlen + len - 8;
305 dir = xmalloc(dirlen + 1);
306 strncpy(dir, path, pathlen);
307 strncpy(dir + pathlen, buf + 8, len - 8);
308 dir[dirlen] = '\0';
309 free(buf);
310 buf = dir;
313 if (!is_git_directory(dir))
314 die("Not a git repository: %s", dir);
315 path = real_path(dir);
317 free(buf);
318 return path;
321 static const char *setup_explicit_git_dir(const char *gitdirenv,
322 char *cwd, int len,
323 int *nongit_ok)
325 const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
326 const char *worktree;
327 char *gitfile;
328 int offset;
330 if (PATH_MAX - 40 < strlen(gitdirenv))
331 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
333 gitfile = (char*)read_gitfile_gently(gitdirenv);
334 if (gitfile) {
335 gitfile = xstrdup(gitfile);
336 gitdirenv = gitfile;
339 if (!is_git_directory(gitdirenv)) {
340 if (nongit_ok) {
341 *nongit_ok = 1;
342 free(gitfile);
343 return NULL;
345 die("Not a git repository: '%s'", gitdirenv);
348 if (check_repository_format_gently(gitdirenv, nongit_ok)) {
349 free(gitfile);
350 return NULL;
353 /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
354 if (work_tree_env)
355 set_git_work_tree(work_tree_env);
356 else if (is_bare_repository_cfg > 0) {
357 if (git_work_tree_cfg) /* #22.2, #30 */
358 die("core.bare and core.worktree do not make sense");
360 /* #18, #26 */
361 set_git_dir(gitdirenv);
362 free(gitfile);
363 return NULL;
365 else if (git_work_tree_cfg) { /* #6, #14 */
366 if (is_absolute_path(git_work_tree_cfg))
367 set_git_work_tree(git_work_tree_cfg);
368 else {
369 char core_worktree[PATH_MAX];
370 if (chdir(gitdirenv))
371 die_errno("Could not chdir to '%s'", gitdirenv);
372 if (chdir(git_work_tree_cfg))
373 die_errno("Could not chdir to '%s'", git_work_tree_cfg);
374 if (!getcwd(core_worktree, PATH_MAX))
375 die_errno("Could not get directory '%s'", git_work_tree_cfg);
376 if (chdir(cwd))
377 die_errno("Could not come back to cwd");
378 set_git_work_tree(core_worktree);
381 else /* #2, #10 */
382 set_git_work_tree(".");
384 /* set_git_work_tree() must have been called by now */
385 worktree = get_git_work_tree();
387 /* both get_git_work_tree() and cwd are already normalized */
388 if (!strcmp(cwd, worktree)) { /* cwd == worktree */
389 set_git_dir(gitdirenv);
390 free(gitfile);
391 return NULL;
394 offset = dir_inside_of(cwd, worktree);
395 if (offset >= 0) { /* cwd inside worktree? */
396 set_git_dir(real_path(gitdirenv));
397 if (chdir(worktree))
398 die_errno("Could not chdir to '%s'", worktree);
399 cwd[len++] = '/';
400 cwd[len] = '\0';
401 free(gitfile);
402 return cwd + offset;
405 /* cwd outside worktree */
406 set_git_dir(gitdirenv);
407 free(gitfile);
408 return NULL;
411 static const char *setup_discovered_git_dir(const char *gitdir,
412 char *cwd, int offset, int len,
413 int *nongit_ok)
415 if (check_repository_format_gently(gitdir, nongit_ok))
416 return NULL;
418 /* --work-tree is set without --git-dir; use discovered one */
419 if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
420 if (offset != len && !is_absolute_path(gitdir))
421 gitdir = xstrdup(real_path(gitdir));
422 if (chdir(cwd))
423 die_errno("Could not come back to cwd");
424 return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
427 /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
428 if (is_bare_repository_cfg > 0) {
429 set_git_dir(offset == len ? gitdir : real_path(gitdir));
430 if (chdir(cwd))
431 die_errno("Could not come back to cwd");
432 return NULL;
435 /* #0, #1, #5, #8, #9, #12, #13 */
436 set_git_work_tree(".");
437 if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
438 set_git_dir(gitdir);
439 inside_git_dir = 0;
440 inside_work_tree = 1;
441 if (offset == len)
442 return NULL;
444 /* Make "offset" point to past the '/', and add a '/' at the end */
445 offset++;
446 cwd[len++] = '/';
447 cwd[len] = 0;
448 return cwd + offset;
451 /* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
452 static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
454 int root_len;
456 if (check_repository_format_gently(".", nongit_ok))
457 return NULL;
459 /* --work-tree is set without --git-dir; use discovered one */
460 if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
461 const char *gitdir;
463 gitdir = offset == len ? "." : xmemdupz(cwd, offset);
464 if (chdir(cwd))
465 die_errno("Could not come back to cwd");
466 return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
469 inside_git_dir = 1;
470 inside_work_tree = 0;
471 if (offset != len) {
472 if (chdir(cwd))
473 die_errno("Cannot come back to cwd");
474 root_len = offset_1st_component(cwd);
475 cwd[offset > root_len ? offset : root_len] = '\0';
476 set_git_dir(cwd);
478 else
479 set_git_dir(".");
480 return NULL;
483 static const char *setup_nongit(const char *cwd, int *nongit_ok)
485 if (!nongit_ok)
486 die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
487 if (chdir(cwd))
488 die_errno("Cannot come back to cwd");
489 *nongit_ok = 1;
490 return NULL;
493 static dev_t get_device_or_die(const char *path, const char *prefix)
495 struct stat buf;
496 if (stat(path, &buf))
497 die_errno("failed to stat '%s%s%s'",
498 prefix ? prefix : "",
499 prefix ? "/" : "", path);
500 return buf.st_dev;
504 * We cannot decide in this function whether we are in the work tree or
505 * not, since the config can only be read _after_ this function was called.
507 static const char *setup_git_directory_gently_1(int *nongit_ok)
509 const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
510 static char cwd[PATH_MAX+1];
511 const char *gitdirenv, *ret;
512 char *gitfile;
513 int len, offset, ceil_offset;
514 dev_t current_device = 0;
515 int one_filesystem = 1;
518 * Let's assume that we are in a git repository.
519 * If it turns out later that we are somewhere else, the value will be
520 * updated accordingly.
522 if (nongit_ok)
523 *nongit_ok = 0;
525 if (!getcwd(cwd, sizeof(cwd)-1))
526 die_errno("Unable to read current working directory");
527 offset = len = strlen(cwd);
530 * If GIT_DIR is set explicitly, we're not going
531 * to do any discovery, but we still do repository
532 * validation.
534 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
535 if (gitdirenv)
536 return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
538 ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
539 if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
540 ceil_offset = 1;
543 * Test in the following order (relative to the cwd):
544 * - .git (file containing "gitdir: <path>")
545 * - .git/
546 * - ./ (bare)
547 * - ../.git
548 * - ../.git/
549 * - ../ (bare)
550 * - ../../.git/
551 * etc.
553 one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
554 if (one_filesystem)
555 current_device = get_device_or_die(".", NULL);
556 for (;;) {
557 gitfile = (char*)read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
558 if (gitfile)
559 gitdirenv = gitfile = xstrdup(gitfile);
560 else {
561 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
562 gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
565 if (gitdirenv) {
566 ret = setup_discovered_git_dir(gitdirenv,
567 cwd, offset, len,
568 nongit_ok);
569 free(gitfile);
570 return ret;
572 free(gitfile);
574 if (is_git_directory("."))
575 return setup_bare_git_dir(cwd, offset, len, nongit_ok);
577 while (--offset > ceil_offset && cwd[offset] != '/');
578 if (offset <= ceil_offset)
579 return setup_nongit(cwd, nongit_ok);
580 if (one_filesystem) {
581 dev_t parent_device = get_device_or_die("..", cwd);
582 if (parent_device != current_device) {
583 if (nongit_ok) {
584 if (chdir(cwd))
585 die_errno("Cannot come back to cwd");
586 *nongit_ok = 1;
587 return NULL;
589 cwd[offset] = '\0';
590 die("Not a git repository (or any parent up to mount parent %s)\n"
591 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
594 if (chdir("..")) {
595 cwd[offset] = '\0';
596 die_errno("Cannot change to '%s/..'", cwd);
601 const char *setup_git_directory_gently(int *nongit_ok)
603 const char *prefix;
605 prefix = setup_git_directory_gently_1(nongit_ok);
606 if (startup_info) {
607 startup_info->have_repository = !nongit_ok || !*nongit_ok;
608 startup_info->prefix = prefix;
610 return prefix;
613 int git_config_perm(const char *var, const char *value)
615 int i;
616 char *endptr;
618 if (value == NULL)
619 return PERM_GROUP;
621 if (!strcmp(value, "umask"))
622 return PERM_UMASK;
623 if (!strcmp(value, "group"))
624 return PERM_GROUP;
625 if (!strcmp(value, "all") ||
626 !strcmp(value, "world") ||
627 !strcmp(value, "everybody"))
628 return PERM_EVERYBODY;
630 /* Parse octal numbers */
631 i = strtol(value, &endptr, 8);
633 /* If not an octal number, maybe true/false? */
634 if (*endptr != 0)
635 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
638 * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
639 * a chmod value to restrict to.
641 switch (i) {
642 case PERM_UMASK: /* 0 */
643 return PERM_UMASK;
644 case OLD_PERM_GROUP: /* 1 */
645 return PERM_GROUP;
646 case OLD_PERM_EVERYBODY: /* 2 */
647 return PERM_EVERYBODY;
650 /* A filemode value was given: 0xxx */
652 if ((i & 0600) != 0600)
653 die("Problem with core.sharedRepository filemode value "
654 "(0%.3o).\nThe owner of files must always have "
655 "read and write permissions.", i);
658 * Mask filemode value. Others can not get write permission.
659 * x flags for directories are handled separately.
661 return -(i & 0666);
664 int check_repository_format_version(const char *var, const char *value, void *cb)
666 if (strcmp(var, "core.repositoryformatversion") == 0)
667 repository_format_version = git_config_int(var, value);
668 else if (strcmp(var, "core.sharedrepository") == 0)
669 shared_repository = git_config_perm(var, value);
670 else if (strcmp(var, "core.bare") == 0) {
671 is_bare_repository_cfg = git_config_bool(var, value);
672 if (is_bare_repository_cfg == 1)
673 inside_work_tree = -1;
674 } else if (strcmp(var, "core.worktree") == 0) {
675 if (!value)
676 return config_error_nonbool(var);
677 free(git_work_tree_cfg);
678 git_work_tree_cfg = xstrdup(value);
679 inside_work_tree = -1;
681 return 0;
684 int check_repository_format(void)
686 return check_repository_format_gently(get_git_dir(), NULL);
690 * Returns the "prefix", a path to the current working directory
691 * relative to the work tree root, or NULL, if the current working
692 * directory is not a strict subdirectory of the work tree root. The
693 * prefix always ends with a '/' character.
695 const char *setup_git_directory(void)
697 return setup_git_directory_gently(NULL);