Add an option not to use link(src, dest) && unlink(src) when that is unreliable
[git/spearce.git] / setup.c
blobebd60de9ce5b52f348819a6a390c15b8dc08d2ff
1 #include "cache.h"
2 #include "dir.h"
4 static int inside_git_dir = -1;
5 static int inside_work_tree = -1;
7 const char *prefix_path(const char *prefix, int len, const char *path)
9 const char *orig = path;
10 char *sanitized = xmalloc(len + strlen(path) + 1);
11 if (is_absolute_path(orig))
12 strcpy(sanitized, path);
13 else {
14 if (len)
15 memcpy(sanitized, prefix, len);
16 strcpy(sanitized + len, path);
18 if (normalize_path_copy(sanitized, sanitized))
19 goto error_out;
20 if (is_absolute_path(orig)) {
21 const char *work_tree = get_git_work_tree();
22 size_t len = strlen(work_tree);
23 size_t total = strlen(sanitized) + 1;
24 if (strncmp(sanitized, work_tree, len) ||
25 (sanitized[len] != '\0' && sanitized[len] != '/')) {
26 error_out:
27 die("'%s' is outside repository", orig);
29 if (sanitized[len] == '/')
30 len++;
31 memmove(sanitized, sanitized + len, total - len);
33 return sanitized;
37 * Unlike prefix_path, this should be used if the named file does
38 * not have to interact with index entry; i.e. name of a random file
39 * on the filesystem.
41 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
43 static char path[PATH_MAX];
44 #ifndef __MINGW32__
45 if (!pfx || !*pfx || is_absolute_path(arg))
46 return arg;
47 memcpy(path, pfx, pfx_len);
48 strcpy(path + pfx_len, arg);
49 #else
50 char *p;
51 /* don't add prefix to absolute paths, but still replace '\' by '/' */
52 if (is_absolute_path(arg))
53 pfx_len = 0;
54 else
55 memcpy(path, pfx, pfx_len);
56 strcpy(path + pfx_len, arg);
57 for (p = path + pfx_len; *p; p++)
58 if (*p == '\\')
59 *p = '/';
60 #endif
61 return path;
65 * Verify a filename that we got as an argument for a pathspec
66 * entry. Note that a filename that begins with "-" never verifies
67 * as true, because even if such a filename were to exist, we want
68 * it to be preceded by the "--" marker (or we want the user to
69 * use a format like "./-filename")
71 void verify_filename(const char *prefix, const char *arg)
73 const char *name;
74 struct stat st;
76 if (*arg == '-')
77 die("bad flag '%s' used after filename", arg);
78 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
79 if (!lstat(name, &st))
80 return;
81 if (errno == ENOENT)
82 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
83 "Use '--' to separate paths from revisions", arg);
84 die("'%s': %s", arg, strerror(errno));
88 * Opposite of the above: the command line did not have -- marker
89 * and we parsed the arg as a refname. It should not be interpretable
90 * as a filename.
92 void verify_non_filename(const char *prefix, const char *arg)
94 const char *name;
95 struct stat st;
97 if (!is_inside_work_tree() || is_inside_git_dir())
98 return;
99 if (*arg == '-')
100 return; /* flag */
101 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
102 if (!lstat(name, &st))
103 die("ambiguous argument '%s': both revision and filename\n"
104 "Use '--' to separate filenames from revisions", arg);
105 if (errno != ENOENT && errno != ENOTDIR)
106 die("'%s': %s", arg, strerror(errno));
109 const char **get_pathspec(const char *prefix, const char **pathspec)
111 const char *entry = *pathspec;
112 const char **src, **dst;
113 int prefixlen;
115 if (!prefix && !entry)
116 return NULL;
118 if (!entry) {
119 static const char *spec[2];
120 spec[0] = prefix;
121 spec[1] = NULL;
122 return spec;
125 /* Otherwise we have to re-write the entries.. */
126 src = pathspec;
127 dst = pathspec;
128 prefixlen = prefix ? strlen(prefix) : 0;
129 while (*src) {
130 const char *p = prefix_path(prefix, prefixlen, *src);
131 *(dst++) = p;
132 src++;
134 *dst = NULL;
135 if (!*pathspec)
136 return NULL;
137 return pathspec;
141 * Test if it looks like we're at a git directory.
142 * We want to see:
144 * - either an objects/ directory _or_ the proper
145 * GIT_OBJECT_DIRECTORY environment variable
146 * - a refs/ directory
147 * - either a HEAD symlink or a HEAD file that is formatted as
148 * a proper "ref:", or a regular file HEAD that has a properly
149 * formatted sha1 object name.
151 static int is_git_directory(const char *suspect)
153 char path[PATH_MAX];
154 size_t len = strlen(suspect);
156 strcpy(path, suspect);
157 if (getenv(DB_ENVIRONMENT)) {
158 if (access(getenv(DB_ENVIRONMENT), X_OK))
159 return 0;
161 else {
162 strcpy(path + len, "/objects");
163 if (access(path, X_OK))
164 return 0;
167 strcpy(path + len, "/refs");
168 if (access(path, X_OK))
169 return 0;
171 strcpy(path + len, "/HEAD");
172 if (validate_headref(path))
173 return 0;
175 return 1;
178 int is_inside_git_dir(void)
180 if (inside_git_dir < 0)
181 inside_git_dir = is_inside_dir(get_git_dir());
182 return inside_git_dir;
185 int is_inside_work_tree(void)
187 if (inside_work_tree < 0)
188 inside_work_tree = is_inside_dir(get_git_work_tree());
189 return inside_work_tree;
193 * set_work_tree() is only ever called if you set GIT_DIR explicitely.
194 * The old behaviour (which we retain here) is to set the work tree root
195 * to the cwd, unless overridden by the config, the command line, or
196 * GIT_WORK_TREE.
198 static const char *set_work_tree(const char *dir)
200 char buffer[PATH_MAX + 1];
202 if (!getcwd(buffer, sizeof(buffer)))
203 die ("Could not get the current working directory");
204 git_work_tree_cfg = xstrdup(buffer);
205 inside_work_tree = 1;
207 return NULL;
210 void setup_work_tree(void)
212 const char *work_tree, *git_dir;
213 static int initialized = 0;
215 if (initialized)
216 return;
217 work_tree = get_git_work_tree();
218 git_dir = get_git_dir();
219 if (!is_absolute_path(git_dir))
220 git_dir = make_absolute_path(git_dir);
221 if (!work_tree || chdir(work_tree))
222 die("This operation must be run in a work tree");
223 set_git_dir(make_relative_path(git_dir, work_tree));
224 initialized = 1;
227 static int check_repository_format_gently(int *nongit_ok)
229 git_config(check_repository_format_version, NULL);
230 if (GIT_REPO_VERSION < repository_format_version) {
231 if (!nongit_ok)
232 die ("Expected git repo version <= %d, found %d",
233 GIT_REPO_VERSION, repository_format_version);
234 warning("Expected git repo version <= %d, found %d",
235 GIT_REPO_VERSION, repository_format_version);
236 warning("Please upgrade Git");
237 *nongit_ok = -1;
238 return -1;
240 return 0;
244 * Try to read the location of the git directory from the .git file,
245 * return path to git directory if found.
247 const char *read_gitfile_gently(const char *path)
249 char *buf;
250 struct stat st;
251 int fd;
252 size_t len;
254 if (stat(path, &st))
255 return NULL;
256 if (!S_ISREG(st.st_mode))
257 return NULL;
258 fd = open(path, O_RDONLY);
259 if (fd < 0)
260 die("Error opening %s: %s", path, strerror(errno));
261 buf = xmalloc(st.st_size + 1);
262 len = read_in_full(fd, buf, st.st_size);
263 close(fd);
264 if (len != st.st_size)
265 die("Error reading %s", path);
266 buf[len] = '\0';
267 if (prefixcmp(buf, "gitdir: "))
268 die("Invalid gitfile format: %s", path);
269 while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
270 len--;
271 if (len < 9)
272 die("No path in gitfile: %s", path);
273 buf[len] = '\0';
274 if (!is_git_directory(buf + 8))
275 die("Not a git repository: %s", buf + 8);
276 path = make_absolute_path(buf + 8);
277 free(buf);
278 return path;
282 * We cannot decide in this function whether we are in the work tree or
283 * not, since the config can only be read _after_ this function was called.
285 const char *setup_git_directory_gently(int *nongit_ok)
287 const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
288 const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
289 static char cwd[PATH_MAX+1];
290 const char *gitdirenv;
291 const char *gitfile_dir;
292 int len, offset, ceil_offset;
295 * Let's assume that we are in a git repository.
296 * If it turns out later that we are somewhere else, the value will be
297 * updated accordingly.
299 if (nongit_ok)
300 *nongit_ok = 0;
303 * If GIT_DIR is set explicitly, we're not going
304 * to do any discovery, but we still do repository
305 * validation.
307 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
308 if (gitdirenv) {
309 if (PATH_MAX - 40 < strlen(gitdirenv))
310 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
311 if (is_git_directory(gitdirenv)) {
312 static char buffer[1024 + 1];
313 const char *retval;
315 if (!work_tree_env) {
316 retval = set_work_tree(gitdirenv);
317 /* config may override worktree */
318 if (check_repository_format_gently(nongit_ok))
319 return NULL;
320 return retval;
322 if (check_repository_format_gently(nongit_ok))
323 return NULL;
324 retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
325 get_git_work_tree());
326 if (!retval || !*retval)
327 return NULL;
328 set_git_dir(make_absolute_path(gitdirenv));
329 if (chdir(work_tree_env) < 0)
330 die ("Could not chdir to %s", work_tree_env);
331 strcat(buffer, "/");
332 return retval;
334 if (nongit_ok) {
335 *nongit_ok = 1;
336 return NULL;
338 die("Not a git repository: '%s'", gitdirenv);
341 if (!getcwd(cwd, sizeof(cwd)-1))
342 die("Unable to read current working directory");
344 ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
345 if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
346 ceil_offset = 1;
349 * Test in the following order (relative to the cwd):
350 * - .git (file containing "gitdir: <path>")
351 * - .git/
352 * - ./ (bare)
353 * - ../.git
354 * - ../.git/
355 * - ../ (bare)
356 * - ../../.git/
357 * etc.
359 offset = len = strlen(cwd);
360 for (;;) {
361 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
362 if (gitfile_dir) {
363 if (set_git_dir(gitfile_dir))
364 die("Repository setup failed");
365 break;
367 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
368 break;
369 if (is_git_directory(".")) {
370 inside_git_dir = 1;
371 if (!work_tree_env)
372 inside_work_tree = 0;
373 if (offset != len) {
374 cwd[offset] = '\0';
375 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
376 } else
377 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
378 check_repository_format_gently(nongit_ok);
379 return NULL;
381 while (--offset > ceil_offset && cwd[offset] != '/');
382 if (offset <= ceil_offset) {
383 if (nongit_ok) {
384 if (chdir(cwd))
385 die("Cannot come back to cwd");
386 *nongit_ok = 1;
387 return NULL;
389 die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
391 if (chdir(".."))
392 die("Cannot change to %s/..: %s", cwd, strerror(errno));
395 inside_git_dir = 0;
396 if (!work_tree_env)
397 inside_work_tree = 1;
398 git_work_tree_cfg = xstrndup(cwd, offset);
399 if (check_repository_format_gently(nongit_ok))
400 return NULL;
401 if (offset == len)
402 return NULL;
404 /* Make "offset" point to past the '/', and add a '/' at the end */
405 offset++;
406 cwd[len++] = '/';
407 cwd[len] = 0;
408 return cwd + offset;
411 int git_config_perm(const char *var, const char *value)
413 int i;
414 char *endptr;
416 if (value == NULL)
417 return PERM_GROUP;
419 if (!strcmp(value, "umask"))
420 return PERM_UMASK;
421 if (!strcmp(value, "group"))
422 return PERM_GROUP;
423 if (!strcmp(value, "all") ||
424 !strcmp(value, "world") ||
425 !strcmp(value, "everybody"))
426 return PERM_EVERYBODY;
428 /* Parse octal numbers */
429 i = strtol(value, &endptr, 8);
431 /* If not an octal number, maybe true/false? */
432 if (*endptr != 0)
433 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
436 * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
437 * a chmod value to restrict to.
439 switch (i) {
440 case PERM_UMASK: /* 0 */
441 return PERM_UMASK;
442 case OLD_PERM_GROUP: /* 1 */
443 return PERM_GROUP;
444 case OLD_PERM_EVERYBODY: /* 2 */
445 return PERM_EVERYBODY;
448 /* A filemode value was given: 0xxx */
450 if ((i & 0600) != 0600)
451 die("Problem with core.sharedRepository filemode value "
452 "(0%.3o).\nThe owner of files must always have "
453 "read and write permissions.", i);
456 * Mask filemode value. Others can not get write permission.
457 * x flags for directories are handled separately.
459 return -(i & 0666);
462 int check_repository_format_version(const char *var, const char *value, void *cb)
464 if (strcmp(var, "core.repositoryformatversion") == 0)
465 repository_format_version = git_config_int(var, value);
466 else if (strcmp(var, "core.sharedrepository") == 0)
467 shared_repository = git_config_perm(var, value);
468 else if (strcmp(var, "core.bare") == 0) {
469 is_bare_repository_cfg = git_config_bool(var, value);
470 if (is_bare_repository_cfg == 1)
471 inside_work_tree = -1;
472 } else if (strcmp(var, "core.worktree") == 0) {
473 if (!value)
474 return config_error_nonbool(var);
475 free(git_work_tree_cfg);
476 git_work_tree_cfg = xstrdup(value);
477 inside_work_tree = -1;
479 return 0;
482 int check_repository_format(void)
484 return check_repository_format_gently(NULL);
487 const char *setup_git_directory(void)
489 const char *retval = setup_git_directory_gently(NULL);
491 /* If the work tree is not the default one, recompute prefix */
492 if (inside_work_tree < 0) {
493 static char buffer[PATH_MAX + 1];
494 char *rel;
495 if (retval && chdir(retval))
496 die ("Could not jump back into original cwd");
497 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
498 if (rel && *rel && chdir(get_git_work_tree()))
499 die ("Could not jump to working directory");
500 return rel && *rel ? strcat(rel, "/") : NULL;
503 return retval;