Link git-shell only to a subset of libgit.a
[git/dscho.git] / setup.c
blob6cf909463d4ad3681a2f35269db9dc944f4389c2
1 #include "cache.h"
2 #include "dir.h"
4 static int inside_git_dir = -1;
5 static int inside_work_tree = -1;
7 static int sanitary_path_copy(char *dst, const char *src)
9 char *dst0;
11 if (has_dos_drive_prefix(src)) {
12 *dst++ = *src++;
13 *dst++ = *src++;
15 dst0 = dst;
17 if (is_dir_sep(*src)) {
18 *dst++ = '/';
19 while (is_dir_sep(*src))
20 src++;
23 for (;;) {
24 char c = *src;
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.
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;
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;
71 up_one:
73 * dst0..dst is prefix portion, and dst[-1] is '/';
74 * go up one level.
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;
89 *dst = '\0';
90 return 0;
93 const char *prefix_path(const char *prefix, int len, const char *path)
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);
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;
117 if (sanitized[len] == '/')
118 len++;
119 memmove(sanitized, sanitized + len, total - len);
121 return sanitized;
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.
129 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
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;
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")
159 void verify_filename(const char *prefix, const char *arg)
161 const char *name;
162 struct stat st;
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));
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.
180 void verify_non_filename(const char *prefix, const char *arg)
182 const char *name;
183 struct stat st;
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));
197 const char **get_pathspec(const char *prefix, const char **pathspec)
199 const char *entry = *pathspec;
200 const char **src, **dst;
201 int prefixlen;
203 if (!prefix && !entry)
204 return NULL;
206 if (!entry) {
207 static const char *spec[2];
208 spec[0] = prefix;
209 spec[1] = NULL;
210 return spec;
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++;
225 *dst = NULL;
226 if (!*pathspec)
227 return NULL;
228 return pathspec;
232 * Test if it looks like we're at a git directory.
233 * We want to see:
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.
242 static int is_git_directory(const char *suspect)
244 char path[PATH_MAX];
245 size_t len = strlen(suspect);
247 strcpy(path, suspect);
248 if (getenv(DB_ENVIRONMENT)) {
249 if (access(getenv(DB_ENVIRONMENT), X_OK))
250 return 0;
252 else {
253 strcpy(path + len, "/objects");
254 if (access(path, X_OK))
255 return 0;
258 strcpy(path + len, "/refs");
259 if (access(path, X_OK))
260 return 0;
262 strcpy(path + len, "/HEAD");
263 if (validate_headref(path))
264 return 0;
266 return 1;
269 int is_inside_git_dir(void)
271 if (inside_git_dir < 0)
272 inside_git_dir = is_inside_dir(get_git_dir());
273 return inside_git_dir;
276 int is_inside_work_tree(void)
278 if (inside_work_tree < 0)
279 inside_work_tree = is_inside_dir(get_git_work_tree());
280 return inside_work_tree;
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.
289 static const char *set_work_tree(const char *dir)
291 char buffer[PATH_MAX + 1];
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;
298 return NULL;
301 void setup_work_tree(void)
303 const char *work_tree, *git_dir;
304 static int initialized = 0;
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;
318 static int check_repository_format_gently(int *nongit_ok)
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;
331 return 0;
335 * Try to read the location of the git directory from the .git file,
336 * return path to git directory if found.
338 const char *read_gitfile_gently(const char *path)
340 char *buf;
341 struct stat st;
342 int fd;
343 size_t len;
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;
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.
376 const char *setup_git_directory_gently(int *nongit_ok)
378 const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
379 const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
380 static char cwd[PATH_MAX+1];
381 const char *gitdirenv;
382 const char *gitfile_dir;
383 int len, offset, ceil_offset;
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.
390 if (nongit_ok)
391 *nongit_ok = 0;
394 * If GIT_DIR is set explicitly, we're not going
395 * to do any discovery, but we still do repository
396 * validation.
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;
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;
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;
425 if (nongit_ok) {
426 *nongit_ok = 1;
427 return NULL;
429 die("Not a git repository: '%s'", gitdirenv);
432 if (!getcwd(cwd, sizeof(cwd)-1))
433 die("Unable to read current working directory");
435 ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
436 if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
437 ceil_offset = 1;
440 * Test in the following order (relative to the cwd):
441 * - .git (file containing "gitdir: <path>")
442 * - .git/
443 * - ./ (bare)
444 * - ../.git
445 * - ../.git/
446 * - ../ (bare)
447 * - ../../.git/
448 * etc.
450 offset = len = strlen(cwd);
451 for (;;) {
452 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
453 if (gitfile_dir) {
454 if (set_git_dir(gitfile_dir))
455 die("Repository setup failed");
456 break;
458 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
459 break;
460 if (is_git_directory(".")) {
461 inside_git_dir = 1;
462 if (!work_tree_env)
463 inside_work_tree = 0;
464 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
465 check_repository_format_gently(nongit_ok);
466 return NULL;
468 while (--offset > ceil_offset && cwd[offset] != '/');
469 if (offset <= ceil_offset) {
470 if (nongit_ok) {
471 if (chdir(cwd))
472 die("Cannot come back to cwd");
473 *nongit_ok = 1;
474 return NULL;
476 die("Not a git repository");
478 chdir("..");
481 inside_git_dir = 0;
482 if (!work_tree_env)
483 inside_work_tree = 1;
484 git_work_tree_cfg = xstrndup(cwd, offset);
485 if (check_repository_format_gently(nongit_ok))
486 return NULL;
487 if (offset == len)
488 return NULL;
490 /* Make "offset" point to past the '/', and add a '/' at the end */
491 offset++;
492 cwd[len++] = '/';
493 cwd[len] = 0;
494 return cwd + offset;
497 int git_config_perm(const char *var, const char *value)
499 int i;
500 char *endptr;
502 if (value == NULL)
503 return PERM_GROUP;
505 if (!strcmp(value, "umask"))
506 return PERM_UMASK;
507 if (!strcmp(value, "group"))
508 return PERM_GROUP;
509 if (!strcmp(value, "all") ||
510 !strcmp(value, "world") ||
511 !strcmp(value, "everybody"))
512 return PERM_EVERYBODY;
514 /* Parse octal numbers */
515 i = strtol(value, &endptr, 8);
517 /* If not an octal number, maybe true/false? */
518 if (*endptr != 0)
519 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
522 * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
523 * a chmod value.
525 switch (i) {
526 case PERM_UMASK: /* 0 */
527 return PERM_UMASK;
528 case OLD_PERM_GROUP: /* 1 */
529 return PERM_GROUP;
530 case OLD_PERM_EVERYBODY: /* 2 */
531 return PERM_EVERYBODY;
534 /* A filemode value was given: 0xxx */
536 if ((i & 0600) != 0600)
537 die("Problem with core.sharedRepository filemode value "
538 "(0%.3o).\nThe owner of files must always have "
539 "read and write permissions.", i);
542 * Mask filemode value. Others can not get write permission.
543 * x flags for directories are handled separately.
545 return i & 0666;
548 int check_repository_format_version(const char *var, const char *value, void *cb)
550 if (strcmp(var, "core.repositoryformatversion") == 0)
551 repository_format_version = git_config_int(var, value);
552 else if (strcmp(var, "core.sharedrepository") == 0)
553 shared_repository = git_config_perm(var, value);
554 else if (strcmp(var, "core.bare") == 0) {
555 is_bare_repository_cfg = git_config_bool(var, value);
556 if (is_bare_repository_cfg == 1)
557 inside_work_tree = -1;
558 } else if (strcmp(var, "core.worktree") == 0) {
559 if (!value)
560 return config_error_nonbool(var);
561 free(git_work_tree_cfg);
562 git_work_tree_cfg = xstrdup(value);
563 inside_work_tree = -1;
565 return 0;
568 int check_repository_format(void)
570 return check_repository_format_gently(NULL);
573 const char *setup_git_directory(void)
575 const char *retval = setup_git_directory_gently(NULL);
577 /* If the work tree is not the default one, recompute prefix */
578 if (inside_work_tree < 0) {
579 static char buffer[PATH_MAX + 1];
580 char *rel;
581 if (retval && chdir(retval))
582 die ("Could not jump back into original cwd");
583 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
584 return rel && *rel ? strcat(rel, "/") : NULL;
587 return retval;