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