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         set_git_dir(make_relative_path(git_dir, work_tree));
 225         initialized = 1;
 226 }
 227
 228 static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 229 {
 230         char repo_config[PATH_MAX+1];
 231
 232         /*
 233          * git_config() can't be used here because it calls git_pathdup()
 234          * to get $GIT_CONFIG/config. That call will make setup_git_env()
 235          * set git_dir to ".git".
 236          *
 237          * We are in gitdir setup, no git dir has been found useable yet.
 238          * Use a gentler version of git_config() to check if this repo
 239          * is a good one.
 240          */
 241         snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
 242         git_config_early(check_repository_format_version, NULL, repo_config);
 243         if (GIT_REPO_VERSION < repository_format_version) {
 244                 if (!nongit_ok)
 245                         die ("Expected git repo version <= %d, found %d",
 246                              GIT_REPO_VERSION, repository_format_version);
 247                 warning("Expected git repo version <= %d, found %d",
 248                         GIT_REPO_VERSION, repository_format_version);
 249                 warning("Please upgrade Git");
 250                 *nongit_ok = -1;
 251                 return -1;
 252         }
 253         return 0;
 254 }
 255
 256 /*
 257  * Try to read the location of the git directory from the .git file,
 258  * return path to git directory if found.
 259  */
 260 const char *read_gitfile_gently(const char *path)
 261 {
 262         char *buf;
 263         char *dir;
 264         const char *slash;
 265         struct stat st;
 266         int fd;
 267         size_t len;
 268
 269         if (stat(path, &st))
 270                 return NULL;
 271         if (!S_ISREG(st.st_mode))
 272                 return NULL;
 273         fd = open(path, O_RDONLY);
 274         if (fd < 0)
 275                 die_errno("Error opening '%s'", path);
 276         buf = xmalloc(st.st_size + 1);
 277         len = read_in_full(fd, buf, st.st_size);
 278         close(fd);
 279         if (len != st.st_size)
 280                 die("Error reading %s", path);
 281         buf[len] = '\0';
 282         if (prefixcmp(buf, "gitdir: "))
 283                 die("Invalid gitfile format: %s", path);
 284         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 285                 len--;
 286         if (len < 9)
 287                 die("No path in gitfile: %s", path);
 288         buf[len] = '\0';
 289         dir = buf + 8;
 290
 291         if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 292                 size_t pathlen = slash+1 - path;
 293                 size_t dirlen = pathlen + len - 8;
 294                 dir = xmalloc(dirlen + 1);
 295                 strncpy(dir, path, pathlen);
 296                 strncpy(dir + pathlen, buf + 8, len - 8);
 297                 dir[dirlen] = '\0';
 298                 free(buf);
 299                 buf = dir;
 300         }
 301
 302         if (!is_git_directory(dir))
 303                 die("Not a git repository: %s", dir);
 304         path = make_absolute_path(dir);
 305
 306         free(buf);
 307         return path;
 308 }
 309
 310 static const char *setup_explicit_git_dir(const char *gitdirenv,
 311                                           char *cwd, int len,
 312                                           int *nongit_ok)
 313 {
 314         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 315         const char *worktree;
 316         char *gitfile;
 317
 318         if (PATH_MAX - 40 < strlen(gitdirenv))
 319                 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 320
 321         gitfile = (char*)read_gitfile_gently(gitdirenv);
 322         if (gitfile) {
 323                 gitfile = xstrdup(gitfile);
 324                 gitdirenv = gitfile;
 325         }
 326
 327         if (!is_git_directory(gitdirenv)) {
 328                 if (nongit_ok) {
 329                         *nongit_ok = 1;
 330                         free(gitfile);
 331                         return NULL;
 332                 }
 333                 die("Not a git repository: '%s'", gitdirenv);
 334         }
 335
 336         if (check_repository_format_gently(gitdirenv, nongit_ok)) {
 337                 free(gitfile);
 338                 return NULL;
 339         }
 340
 341         /* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
 342         if (work_tree_env)
 343                 set_git_work_tree(work_tree_env);
 344         else if (is_bare_repository_cfg > 0) {
 345                 if (git_work_tree_cfg) /* #22.2, #30 */
 346                         die("core.bare and core.worktree do not make sense");
 347
 348                 /* #18, #26 */
 349                 set_git_dir(gitdirenv);
 350                 free(gitfile);
 351                 return NULL;
 352         }
 353         else if (git_work_tree_cfg) { /* #6, #14 */
 354                 if (is_absolute_path(git_work_tree_cfg))
 355                         set_git_work_tree(git_work_tree_cfg);
 356                 else {
 357                         char core_worktree[PATH_MAX];
 358                         if (chdir(gitdirenv))
 359                                 die_errno("Could not chdir to '%s'", gitdirenv);
 360                         if (chdir(git_work_tree_cfg))
 361                                 die_errno("Could not chdir to '%s'", git_work_tree_cfg);
 362                         if (!getcwd(core_worktree, PATH_MAX))
 363                                 die_errno("Could not get directory '%s'", git_work_tree_cfg);
 364                         if (chdir(cwd))
 365                                 die_errno("Could not come back to cwd");
 366                         set_git_work_tree(core_worktree);
 367                 }
 368         }
 369         else /* #2, #10 */
 370                 set_git_work_tree(".");
 371
 372         /* set_git_work_tree() must have been called by now */
 373         worktree = get_git_work_tree();
 374
 375         /* both get_git_work_tree() and cwd are already normalized */
 376         if (!strcmp(cwd, worktree)) { /* cwd == worktree */
 377                 set_git_dir(gitdirenv);
 378                 free(gitfile);
 379                 return NULL;
 380         }
 381
 382         if (!prefixcmp(cwd, worktree) &&
 383             cwd[strlen(worktree)] == '/') { /* cwd inside worktree */
 384                 set_git_dir(make_absolute_path(gitdirenv));
 385                 if (chdir(worktree))
 386                         die_errno("Could not chdir to '%s'", worktree);
 387                 cwd[len++] = '/';
 388                 cwd[len] = '\0';
 389                 free(gitfile);
 390                 return cwd + strlen(worktree) + 1;
 391         }
 392
 393         /* cwd outside worktree */
 394         set_git_dir(gitdirenv);
 395         free(gitfile);
 396         return NULL;
 397 }
 398
 399 static const char *setup_discovered_git_dir(const char *gitdir,
 400                                             char *cwd, int offset, int len,
 401                                             int *nongit_ok)
 402 {
 403         if (check_repository_format_gently(gitdir, nongit_ok))
 404                 return NULL;
 405
 406         /* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
 407         if (is_bare_repository_cfg > 0) {
 408                 set_git_dir(offset == len ? gitdir : make_absolute_path(gitdir));
 409                 if (chdir(cwd))
 410                         die_errno("Could not come back to cwd");
 411                 return NULL;
 412         }
 413
 414         /* #0, #1, #5, #8, #9, #12, #13 */
 415         set_git_work_tree(".");
 416         if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
 417                 set_git_dir(gitdir);
 418         inside_git_dir = 0;
 419         inside_work_tree = 1;
 420         if (offset == len)
 421                 return NULL;
 422
 423         /* Make "offset" point to past the '/', and add a '/' at the end */
 424         offset++;
 425         cwd[len++] = '/';
 426         cwd[len] = 0;
 427         return cwd + offset;
 428 }
 429
 430 /* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
 431 static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
 432 {
 433         int root_len;
 434
 435         if (check_repository_format_gently(".", nongit_ok))
 436                 return NULL;
 437
 438         inside_git_dir = 1;
 439         inside_work_tree = 0;
 440         if (offset != len) {
 441                 if (chdir(cwd))
 442                         die_errno("Cannot come back to cwd");
 443                 root_len = offset_1st_component(cwd);
 444                 cwd[offset > root_len ? offset : root_len] = '\0';
 445                 set_git_dir(cwd);
 446         }
 447         else
 448                 set_git_dir(".");
 449         return NULL;
 450 }
 451
 452 static const char *setup_nongit(const char *cwd, int *nongit_ok)
 453 {
 454         if (!nongit_ok)
 455                 die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 456         if (chdir(cwd))
 457                 die_errno("Cannot come back to cwd");
 458         *nongit_ok = 1;
 459         return NULL;
 460 }
 461
 462 static dev_t get_device_or_die(const char *path, const char *prefix)
 463 {
 464         struct stat buf;
 465         if (stat(path, &buf))
 466                 die_errno("failed to stat '%s%s%s'",
 467                                 prefix ? prefix : "",
 468                                 prefix ? "/" : "", path);
 469         return buf.st_dev;
 470 }
 471
 472 /*
 473  * We cannot decide in this function whether we are in the work tree or
 474  * not, since the config can only be read _after_ this function was called.
 475  */
 476 static const char *setup_git_directory_gently_1(int *nongit_ok)
 477 {
 478         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 479         static char cwd[PATH_MAX+1];
 480         const char *gitdirenv, *ret;
 481         char *gitfile;
 482         int len, offset, ceil_offset;
 483         dev_t current_device = 0;
 484         int one_filesystem = 1;
 485
 486         /*
 487          * Let's assume that we are in a git repository.
 488          * If it turns out later that we are somewhere else, the value will be
 489          * updated accordingly.
 490          */
 491         if (nongit_ok)
 492                 *nongit_ok = 0;
 493
 494         if (!getcwd(cwd, sizeof(cwd)-1))
 495                 die_errno("Unable to read current working directory");
 496         offset = len = strlen(cwd);
 497
 498         /*
 499          * If GIT_DIR is set explicitly, we're not going
 500          * to do any discovery, but we still do repository
 501          * validation.
 502          */
 503         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 504         if (gitdirenv)
 505                 return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
 506
 507         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 508         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 509                 ceil_offset = 1;
 510
 511         /*
 512          * Test in the following order (relative to the cwd):
 513          * - .git (file containing "gitdir: <path>")
 514          * - .git/
 515          * - ./ (bare)
 516          * - ../.git
 517          * - ../.git/
 518          * - ../ (bare)
 519          * - ../../.git/
 520          *   etc.
 521          */
 522         one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 523         if (one_filesystem)
 524                 current_device = get_device_or_die(".", NULL);
 525         for (;;) {
 526                 gitfile = (char*)read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 527                 if (gitfile)
 528                         gitdirenv = gitfile = xstrdup(gitfile);
 529                 else {
 530                         if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 531                                 gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
 532                 }
 533
 534                 if (gitdirenv) {
 535                         ret = setup_discovered_git_dir(gitdirenv,
 536                                                        cwd, offset, len,
 537                                                        nongit_ok);
 538                         free(gitfile);
 539                         return ret;
 540                 }
 541                 free(gitfile);
 542
 543                 if (is_git_directory("."))
 544                         return setup_bare_git_dir(cwd, offset, len, nongit_ok);
 545
 546                 while (--offset > ceil_offset && cwd[offset] != '/');
 547                 if (offset <= ceil_offset)
 548                         return setup_nongit(cwd, nongit_ok);
 549                 if (one_filesystem) {
 550                         dev_t parent_device = get_device_or_die("..", cwd);
 551                         if (parent_device != current_device) {
 552                                 if (nongit_ok) {
 553                                         if (chdir(cwd))
 554                                                 die_errno("Cannot come back to cwd");
 555                                         *nongit_ok = 1;
 556                                         return NULL;
 557                                 }
 558                                 cwd[offset] = '\0';
 559                                 die("Not a git repository (or any parent up to mount parent %s)\n"
 560                                 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 561                         }
 562                 }
 563                 if (chdir("..")) {
 564                         cwd[offset] = '\0';
 565                         die_errno("Cannot change to '%s/..'", cwd);
 566                 }
 567         }
 568 }
 569
 570 const char *setup_git_directory_gently(int *nongit_ok)
 571 {
 572         const char *prefix;
 573
 574         prefix = setup_git_directory_gently_1(nongit_ok);
 575         if (startup_info) {
 576                 startup_info->have_repository = !nongit_ok || !*nongit_ok;
 577                 startup_info->prefix = prefix;
 578         }
 579         return prefix;
 580 }
 581
 582 int git_config_perm(const char *var, const char *value)
 583 {
 584         int i;
 585         char *endptr;
 586
 587         if (value == NULL)
 588                 return PERM_GROUP;
 589
 590         if (!strcmp(value, "umask"))
 591                 return PERM_UMASK;
 592         if (!strcmp(value, "group"))
 593                 return PERM_GROUP;
 594         if (!strcmp(value, "all") ||
 595             !strcmp(value, "world") ||
 596             !strcmp(value, "everybody"))
 597                 return PERM_EVERYBODY;
 598
 599         /* Parse octal numbers */
 600         i = strtol(value, &endptr, 8);
 601
 602         /* If not an octal number, maybe true/false? */
 603         if (*endptr != 0)
 604                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 605
 606         /*
 607          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 608          * a chmod value to restrict to.
 609          */
 610         switch (i) {
 611         case PERM_UMASK:               /* 0 */
 612                 return PERM_UMASK;
 613         case OLD_PERM_GROUP:           /* 1 */
 614                 return PERM_GROUP;
 615         case OLD_PERM_EVERYBODY:       /* 2 */
 616                 return PERM_EVERYBODY;
 617         }
 618
 619         /* A filemode value was given: 0xxx */
 620
 621         if ((i & 0600) != 0600)
 622                 die("Problem with core.sharedRepository filemode value "
 623                     "(0%.3o).\nThe owner of files must always have "
 624                     "read and write permissions.", i);
 625
 626         /*
 627          * Mask filemode value. Others can not get write permission.
 628          * x flags for directories are handled separately.
 629          */
 630         return -(i & 0666);
 631 }
 632
 633 int check_repository_format_version(const char *var, const char *value, void *cb)
 634 {
 635         if (strcmp(var, "core.repositoryformatversion") == 0)
 636                 repository_format_version = git_config_int(var, value);
 637         else if (strcmp(var, "core.sharedrepository") == 0)
 638                 shared_repository = git_config_perm(var, value);
 639         else if (strcmp(var, "core.bare") == 0) {
 640                 is_bare_repository_cfg = git_config_bool(var, value);
 641                 if (is_bare_repository_cfg == 1)
 642                         inside_work_tree = -1;
 643         } else if (strcmp(var, "core.worktree") == 0) {
 644                 if (!value)
 645                         return config_error_nonbool(var);
 646                 free(git_work_tree_cfg);
 647                 git_work_tree_cfg = xstrdup(value);
 648                 inside_work_tree = -1;
 649         }
 650         return 0;
 651 }
 652
 653 int check_repository_format(void)
 654 {
 655         return check_repository_format_gently(get_git_dir(), NULL);
 656 }
 657
 658 /*
 659  * Returns the "prefix", a path to the current working directory
 660  * relative to the work tree root, or NULL, if the current working
 661  * directory is not a strict subdirectory of the work tree root. The
 662  * prefix always ends with a '/' character.
 663  */
 664 const char *setup_git_directory(void)
 665 {
 666         return setup_git_directory_gently(NULL);
 667 }