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 char *prefix_path(const char *prefix, int len, const char *path)
   8 {
   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);
  17         }
  18         if (normalize_path_copy(sanitized, sanitized))
  19                 goto error_out;
  20         if (is_absolute_path(orig)) {
  21                 size_t root_len, len, total;
  22                 const char *work_tree = get_git_work_tree();
  23                 if (!work_tree)
  24                         goto error_out;
  25                 len = strlen(work_tree);
  26                 root_len = offset_1st_component(work_tree);
  27                 total = strlen(sanitized) + 1;
  28                 if (strncmp(sanitized, work_tree, len) ||
  29                     (len > root_len && sanitized[len] != '\0' && sanitized[len] != '/')) {
  30                 error_out:
  31                         die("'%s' is outside repository", orig);
  32                 }
  33                 if (sanitized[len] == '/')
  34                         len++;
  35                 memmove(sanitized, sanitized + len, total - len);
  36         }
  37         return sanitized;
  38 }
  39
  40 /*
  41  * Unlike prefix_path, this should be used if the named file does
  42  * not have to interact with index entry; i.e. name of a random file
  43  * on the filesystem.
  44  */
  45 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
  46 {
  47         static char path[PATH_MAX];
  48 #ifndef WIN32
  49         if (!pfx_len || is_absolute_path(arg))
  50                 return arg;
  51         memcpy(path, pfx, pfx_len);
  52         strcpy(path + pfx_len, arg);
  53 #else
  54         char *p;
  55         /* don't add prefix to absolute paths, but still replace '\' by '/' */
  56         if (is_absolute_path(arg))
  57                 pfx_len = 0;
  58         else if (pfx_len)
  59                 memcpy(path, pfx, pfx_len);
  60         strcpy(path + pfx_len, arg);
  61         for (p = path + pfx_len; *p; p++)
  62                 if (*p == '\\')
  63                         *p = '/';
  64 #endif
  65         return path;
  66 }
  67
  68 int check_filename(const char *prefix, const char *arg)
  69 {
  70         const char *name;
  71         struct stat st;
  72
  73         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  74         if (!lstat(name, &st))
  75                 return 1; /* file exists */
  76         if (errno == ENOENT || errno == ENOTDIR)
  77                 return 0; /* file does not exist */
  78         die_errno("failed to stat '%s'", arg);
  79 }
  80
  81 static void NORETURN die_verify_filename(const char *prefix, const char *arg)
  82 {
  83         unsigned char sha1[20];
  84         unsigned mode;
  85         /* try a detailed diagnostic ... */
  86         get_sha1_with_mode_1(arg, sha1, &mode, 0, prefix);
  87         /* ... or fall back the most general message. */
  88         die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  89             "Use '--' to separate paths from revisions", arg);
  90
  91 }
  92
  93 /*
  94  * Verify a filename that we got as an argument for a pathspec
  95  * entry. Note that a filename that begins with "-" never verifies
  96  * as true, because even if such a filename were to exist, we want
  97  * it to be preceded by the "--" marker (or we want the user to
  98  * use a format like "./-filename")
  99  */
 100 void verify_filename(const char *prefix, const char *arg)
 101 {
 102         if (*arg == '-')
 103                 die("bad flag '%s' used after filename", arg);
 104         if (check_filename(prefix, arg))
 105                 return;
 106         die_verify_filename(prefix, arg);
 107 }
 108
 109 /*
 110  * Opposite of the above: the command line did not have -- marker
 111  * and we parsed the arg as a refname.  It should not be interpretable
 112  * as a filename.
 113  */
 114 void verify_non_filename(const char *prefix, const char *arg)
 115 {
 116         if (!is_inside_work_tree() || is_inside_git_dir())
 117                 return;
 118         if (*arg == '-')
 119                 return; /* flag */
 120         if (!check_filename(prefix, arg))
 121                 return;
 122         die("ambiguous argument '%s': both revision and filename\n"
 123             "Use '--' to separate filenames from revisions", arg);
 124 }
 125
 126 const char **get_pathspec(const char *prefix, const char **pathspec)
 127 {
 128         const char *entry = *pathspec;
 129         const char **src, **dst;
 130         int prefixlen;
 131
 132         if (!prefix && !entry)
 133                 return NULL;
 134
 135         if (!entry) {
 136                 static const char *spec[2];
 137                 spec[0] = prefix;
 138                 spec[1] = NULL;
 139                 return spec;
 140         }
 141
 142         /* Otherwise we have to re-write the entries.. */
 143         src = pathspec;
 144         dst = pathspec;
 145         prefixlen = prefix ? strlen(prefix) : 0;
 146         while (*src) {
 147                 const char *p = prefix_path(prefix, prefixlen, *src);
 148                 *(dst++) = p;
 149                 src++;
 150         }
 151         *dst = NULL;
 152         if (!*pathspec)
 153                 return NULL;
 154         return pathspec;
 155 }
 156
 157 /*
 158  * Test if it looks like we're at a git directory.
 159  * We want to see:
 160  *
 161  *  - either an objects/ directory _or_ the proper
 162  *    GIT_OBJECT_DIRECTORY environment variable
 163  *  - a refs/ directory
 164  *  - either a HEAD symlink or a HEAD file that is formatted as
 165  *    a proper "ref:", or a regular file HEAD that has a properly
 166  *    formatted sha1 object name.
 167  */
 168 static int is_git_directory(const char *suspect)
 169 {
 170         char path[PATH_MAX];
 171         size_t len = strlen(suspect);
 172
 173         if (PATH_MAX <= len + strlen("/objects"))
 174                 die("Too long path: %.*s", 60, suspect);
 175         strcpy(path, suspect);
 176         if (getenv(DB_ENVIRONMENT)) {
 177                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 178                         return 0;
 179         }
 180         else {
 181                 strcpy(path + len, "/objects");
 182                 if (access(path, X_OK))
 183                         return 0;
 184         }
 185
 186         strcpy(path + len, "/refs");
 187         if (access(path, X_OK))
 188                 return 0;
 189
 190         strcpy(path + len, "/HEAD");
 191         if (validate_headref(path))
 192                 return 0;
 193
 194         return 1;
 195 }
 196
 197 int is_inside_git_dir(void)
 198 {
 199         if (inside_git_dir < 0)
 200                 inside_git_dir = is_inside_dir(get_git_dir());
 201         return inside_git_dir;
 202 }
 203
 204 int is_inside_work_tree(void)
 205 {
 206         if (inside_work_tree < 0)
 207                 inside_work_tree = is_inside_dir(get_git_work_tree());
 208         return inside_work_tree;
 209 }
 210
 211 void setup_work_tree(void)
 212 {
 213         const char *work_tree, *git_dir;
 214         static int initialized = 0;
 215
 216         if (initialized)
 217                 return;
 218         work_tree = get_git_work_tree();
 219         git_dir = get_git_dir();
 220         if (!is_absolute_path(git_dir))
 221                 git_dir = make_absolute_path(git_dir);
 222         if (!work_tree || chdir(work_tree))
 223                 die("This operation must be run in a work tree");
 224
 225         /*
 226          * Make sure subsequent git processes find correct worktree
 227          * if $GIT_WORK_TREE is set relative
 228          */
 229         if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 230                 setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 231
 232         set_git_dir(make_relative_path(git_dir, work_tree));
 233         initialized = 1;
 234 }
 235
 236 static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 237 {
 238         char repo_config[PATH_MAX+1];
 239
 240         /*
 241          * git_config() can't be used here because it calls git_pathdup()
 242          * to get $GIT_CONFIG/config. That call will make setup_git_env()
 243          * set git_dir to ".git".
 244          *
 245          * We are in gitdir setup, no git dir has been found useable yet.
 246          * Use a gentler version of git_config() to check if this repo
 247          * is a good one.
 248          */
 249         snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
 250         git_config_early(check_repository_format_version, NULL, repo_config);
 251         if (GIT_REPO_VERSION < repository_format_version) {
 252                 if (!nongit_ok)
 253                         die ("Expected git repo version <= %d, found %d",
 254                              GIT_REPO_VERSION, repository_format_version);
 255                 warning("Expected git repo version <= %d, found %d",
 256                         GIT_REPO_VERSION, repository_format_version);
 257                 warning("Please upgrade Git");
 258                 *nongit_ok = -1;
 259                 return -1;
 260         }
 261         return 0;
 262 }
 263
 264 /*
 265  * Try to read the location of the git directory from the .git file,
 266  * return path to git directory if found.
 267  */
 268 const char *read_gitfile_gently(const char *path)
 269 {
 270         char *buf;
 271         char *dir;
 272         const char *slash;
 273         struct stat st;
 274         int fd;
 275         size_t len;
 276
 277         if (stat(path, &st))
 278                 return NULL;
 279         if (!S_ISREG(st.st_mode))
 280                 return NULL;
 281         fd = open(path, O_RDONLY);
 282         if (fd < 0)
 283                 die_errno("Error opening '%s'", path);
 284         buf = xmalloc(st.st_size + 1);
 285         len = read_in_full(fd, buf, st.st_size);
 286         close(fd);
 287         if (len != st.st_size)
 288                 die("Error reading %s", path);
 289         buf[len] = '\0';
 290         if (prefixcmp(buf, "gitdir: "))
 291                 die("Invalid gitfile format: %s", path);
 292         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 293                 len--;
 294         if (len < 9)
 295                 die("No path in gitfile: %s", path);
 296         buf[len] = '\0';
 297         dir = buf + 8;
 298
 299         if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 300                 size_t pathlen = slash+1 - path;
 301                 size_t dirlen = pathlen + len - 8;
 302                 dir = xmalloc(dirlen + 1);
 303                 strncpy(dir, path, pathlen);
 304                 strncpy(dir + pathlen, buf + 8, len - 8);
 305                 dir[dirlen] = '\0';
 306                 free(buf);
 307                 buf = dir;
 308         }
 309
 310         if (!is_git_directory(dir))
 311                 die("Not a git repository: %s", dir);
 312         path = make_absolute_path(dir);
 313
 314         free(buf);
 315         return path;
 316 }
 317
 318 static const char *setup_explicit_git_dir(const char *gitdirenv,
 319                                           char *cwd, int len,
 320                                           int *nongit_ok)
 321 {
 322         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 323         const char *worktree;
 324         char *gitfile;
 325
 326         if (PATH_MAX - 40 < strlen(gitdirenv))
 327                 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 328
 329         gitfile = (char*)read_gitfile_gently(gitdirenv);
 330         if (gitfile) {
 331                 gitfile = xstrdup(gitfile);
 332                 gitdirenv = gitfile;
 333         }
 334
 335         if (!is_git_directory(gitdirenv)) {
 336                 if (nongit_ok) {
 337                         *nongit_ok = 1;
 338                         free(gitfile);
 339                         return NULL;
 340                 }
 341                 die("Not a git repository: '%s'", gitdirenv);
 342         }
 343
 344         if (check_repository_format_gently(gitdirenv, nongit_ok)) {
 345                 free(gitfile);
 346                 return NULL;
 347         }
 348
 349         /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
 350         if (work_tree_env)
 351                 set_git_work_tree(work_tree_env);
 352         else if (is_bare_repository_cfg > 0) {
 353                 if (git_work_tree_cfg) /* #22.2, #30 */
 354                         die("core.bare and core.worktree do not make sense");
 355
 356                 /* #18, #26 */
 357                 set_git_dir(gitdirenv);
 358                 free(gitfile);
 359                 return NULL;
 360         }
 361         else if (git_work_tree_cfg) { /* #6, #14 */
 362                 if (is_absolute_path(git_work_tree_cfg))
 363                         set_git_work_tree(git_work_tree_cfg);
 364                 else {
 365                         char core_worktree[PATH_MAX];
 366                         if (chdir(gitdirenv))
 367                                 die_errno("Could not chdir to '%s'", gitdirenv);
 368                         if (chdir(git_work_tree_cfg))
 369                                 die_errno("Could not chdir to '%s'", git_work_tree_cfg);
 370                         if (!getcwd(core_worktree, PATH_MAX))
 371                                 die_errno("Could not get directory '%s'", git_work_tree_cfg);
 372                         if (chdir(cwd))
 373                                 die_errno("Could not come back to cwd");
 374                         set_git_work_tree(core_worktree);
 375                 }
 376         }
 377         else /* #2, #10 */
 378                 set_git_work_tree(".");
 379
 380         /* set_git_work_tree() must have been called by now */
 381         worktree = get_git_work_tree();
 382
 383         /* both get_git_work_tree() and cwd are already normalized */
 384         if (!strcmp(cwd, worktree)) { /* cwd == worktree */
 385                 set_git_dir(gitdirenv);
 386                 free(gitfile);
 387                 return NULL;
 388         }
 389
 390         if (!prefixcmp(cwd, worktree) &&
 391             cwd[strlen(worktree)] == '/') { /* cwd inside worktree */
 392                 set_git_dir(make_absolute_path(gitdirenv));
 393                 if (chdir(worktree))
 394                         die_errno("Could not chdir to '%s'", worktree);
 395                 cwd[len++] = '/';
 396                 cwd[len] = '\0';
 397                 free(gitfile);
 398                 return cwd + strlen(worktree) + 1;
 399         }
 400
 401         /* cwd outside worktree */
 402         set_git_dir(gitdirenv);
 403         free(gitfile);
 404         return NULL;
 405 }
 406
 407 static const char *setup_discovered_git_dir(const char *gitdir,
 408                                             char *cwd, int offset, int len,
 409                                             int *nongit_ok)
 410 {
 411         if (check_repository_format_gently(gitdir, nongit_ok))
 412                 return NULL;
 413
 414         /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
 415         if (is_bare_repository_cfg > 0) {
 416                 set_git_dir(offset == len ? gitdir : make_absolute_path(gitdir));
 417                 if (chdir(cwd))
 418                         die_errno("Could not come back to cwd");
 419                 return NULL;
 420         }
 421
 422         /* #0, #1, #5, #8, #9, #12, #13 */
 423         set_git_work_tree(".");
 424         if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
 425                 set_git_dir(gitdir);
 426         inside_git_dir = 0;
 427         inside_work_tree = 1;
 428         if (offset == len)
 429                 return NULL;
 430
 431         /* Make "offset" point to past the '/', and add a '/' at the end */
 432         offset++;
 433         cwd[len++] = '/';
 434         cwd[len] = 0;
 435         return cwd + offset;
 436 }
 437
 438 /* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
 439 static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
 440 {
 441         int root_len;
 442
 443         if (check_repository_format_gently(".", nongit_ok))
 444                 return NULL;
 445
 446         inside_git_dir = 1;
 447         inside_work_tree = 0;
 448         if (offset != len) {
 449                 if (chdir(cwd))
 450                         die_errno("Cannot come back to cwd");
 451                 root_len = offset_1st_component(cwd);
 452                 cwd[offset > root_len ? offset : root_len] = '\0';
 453                 set_git_dir(cwd);
 454         }
 455         else
 456                 set_git_dir(".");
 457         return NULL;
 458 }
 459
 460 static const char *setup_nongit(const char *cwd, int *nongit_ok)
 461 {
 462         if (!nongit_ok)
 463                 die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 464         if (chdir(cwd))
 465                 die_errno("Cannot come back to cwd");
 466         *nongit_ok = 1;
 467         return NULL;
 468 }
 469
 470 static dev_t get_device_or_die(const char *path, const char *prefix)
 471 {
 472         struct stat buf;
 473         if (stat(path, &buf))
 474                 die_errno("failed to stat '%s%s%s'",
 475                                 prefix ? prefix : "",
 476                                 prefix ? "/" : "", path);
 477         return buf.st_dev;
 478 }
 479
 480 /*
 481  * We cannot decide in this function whether we are in the work tree or
 482  * not, since the config can only be read _after_ this function was called.
 483  */
 484 static const char *setup_git_directory_gently_1(int *nongit_ok)
 485 {
 486         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 487         static char cwd[PATH_MAX+1];
 488         const char *gitdirenv, *ret;
 489         char *gitfile;
 490         int len, offset, ceil_offset;
 491         dev_t current_device = 0;
 492         int one_filesystem = 1;
 493
 494         /*
 495          * Let's assume that we are in a git repository.
 496          * If it turns out later that we are somewhere else, the value will be
 497          * updated accordingly.
 498          */
 499         if (nongit_ok)
 500                 *nongit_ok = 0;
 501
 502         if (!getcwd(cwd, sizeof(cwd)-1))
 503                 die_errno("Unable to read current working directory");
 504         offset = len = strlen(cwd);
 505
 506         /*
 507          * If GIT_DIR is set explicitly, we're not going
 508          * to do any discovery, but we still do repository
 509          * validation.
 510          */
 511         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 512         if (gitdirenv)
 513                 return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
 514
 515         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 516         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 517                 ceil_offset = 1;
 518
 519         /*
 520          * Test in the following order (relative to the cwd):
 521          * - .git (file containing "gitdir: <path>")
 522          * - .git/
 523          * - ./ (bare)
 524          * - ../.git
 525          * - ../.git/
 526          * - ../ (bare)
 527          * - ../../.git/
 528          *   etc.
 529          */
 530         one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 531         if (one_filesystem)
 532                 current_device = get_device_or_die(".", NULL);
 533         for (;;) {
 534                 gitfile = (char*)read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 535                 if (gitfile)
 536                         gitdirenv = gitfile = xstrdup(gitfile);
 537                 else {
 538                         if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 539                                 gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 540                 }
 541
 542                 if (gitdirenv) {
 543                         ret = setup_discovered_git_dir(gitdirenv,
 544                                                        cwd, offset, len,
 545                                                        nongit_ok);
 546                         free(gitfile);
 547                         return ret;
 548                 }
 549                 free(gitfile);
 550
 551                 if (is_git_directory("."))
 552                         return setup_bare_git_dir(cwd, offset, len, nongit_ok);
 553
 554                 while (--offset > ceil_offset && cwd[offset] != '/');
 555                 if (offset <= ceil_offset)
 556                         return setup_nongit(cwd, nongit_ok);
 557                 if (one_filesystem) {
 558                         dev_t parent_device = get_device_or_die("..", cwd);
 559                         if (parent_device != current_device) {
 560                                 if (nongit_ok) {
 561                                         if (chdir(cwd))
 562                                                 die_errno("Cannot come back to cwd");
 563                                         *nongit_ok = 1;
 564                                         return NULL;
 565                                 }
 566                                 cwd[offset] = '\0';
 567                                 die("Not a git repository (or any parent up to mount parent %s)\n"
 568                                 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 569                         }
 570                 }
 571                 if (chdir("..")) {
 572                         cwd[offset] = '\0';
 573                         die_errno("Cannot change to '%s/..'", cwd);
 574                 }
 575         }
 576 }
 577
 578 const char *setup_git_directory_gently(int *nongit_ok)
 579 {
 580         const char *prefix;
 581
 582         prefix = setup_git_directory_gently_1(nongit_ok);
 583         if (startup_info) {
 584                 startup_info->have_repository = !nongit_ok || !*nongit_ok;
 585                 startup_info->prefix = prefix;
 586         }
 587         return prefix;
 588 }
 589
 590 int git_config_perm(const char *var, const char *value)
 591 {
 592         int i;
 593         char *endptr;
 594
 595         if (value == NULL)
 596                 return PERM_GROUP;
 597
 598         if (!strcmp(value, "umask"))
 599                 return PERM_UMASK;
 600         if (!strcmp(value, "group"))
 601                 return PERM_GROUP;
 602         if (!strcmp(value, "all") ||
 603             !strcmp(value, "world") ||
 604             !strcmp(value, "everybody"))
 605                 return PERM_EVERYBODY;
 606
 607         /* Parse octal numbers */
 608         i = strtol(value, &endptr, 8);
 609
 610         /* If not an octal number, maybe true/false? */
 611         if (*endptr != 0)
 612                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 613
 614         /*
 615          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 616          * a chmod value to restrict to.
 617          */
 618         switch (i) {
 619         case PERM_UMASK:               /* 0 */
 620                 return PERM_UMASK;
 621         case OLD_PERM_GROUP:           /* 1 */
 622                 return PERM_GROUP;
 623         case OLD_PERM_EVERYBODY:       /* 2 */
 624                 return PERM_EVERYBODY;
 625         }
 626
 627         /* A filemode value was given: 0xxx */
 628
 629         if ((i & 0600) != 0600)
 630                 die("Problem with core.sharedRepository filemode value "
 631                     "(0%.3o).\nThe owner of files must always have "
 632                     "read and write permissions.", i);
 633
 634         /*
 635          * Mask filemode value. Others can not get write permission.
 636          * x flags for directories are handled separately.
 637          */
 638         return -(i & 0666);
 639 }
 640
 641 int check_repository_format_version(const char *var, const char *value, void *cb)
 642 {
 643         if (strcmp(var, "core.repositoryformatversion") == 0)
 644                 repository_format_version = git_config_int(var, value);
 645         else if (strcmp(var, "core.sharedrepository") == 0)
 646                 shared_repository = git_config_perm(var, value);
 647         else if (strcmp(var, "core.bare") == 0) {
 648                 is_bare_repository_cfg = git_config_bool(var, value);
 649                 if (is_bare_repository_cfg == 1)
 650                         inside_work_tree = -1;
 651         } else if (strcmp(var, "core.worktree") == 0) {
 652                 if (!value)
 653                         return config_error_nonbool(var);
 654                 free(git_work_tree_cfg);
 655                 git_work_tree_cfg = xstrdup(value);
 656                 inside_work_tree = -1;
 657         }
 658         return 0;
 659 }
 660
 661 int check_repository_format(void)
 662 {
 663         return check_repository_format_gently(get_git_dir(), NULL);
 664 }
 665
 666 /*
 667  * Returns the "prefix", a path to the current working directory
 668  * relative to the work tree root, or NULL, if the current working
 669  * directory is not a strict subdirectory of the work tree root. The
 670  * prefix always ends with a '/' character.
 671  */
 672 const char *setup_git_directory(void)
 673 {
 674         return setup_git_directory_gently(NULL);
 675 }