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 const 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 || !*pfx || 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
  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 /*
 212  * set_work_tree() is only ever called if you set GIT_DIR explicitly.
 213  * The old behaviour (which we retain here) is to set the work tree root
 214  * to the cwd, unless overridden by the config, the command line, or
 215  * GIT_WORK_TREE.
 216  */
 217 static const char *set_work_tree(const char *dir)
 218 {
 219         char buffer[PATH_MAX + 1];
 220
 221         if (!getcwd(buffer, sizeof(buffer)))
 222                 die ("Could not get the current working directory");
 223         git_work_tree_cfg = xstrdup(buffer);
 224         inside_work_tree = 1;
 225
 226         return NULL;
 227 }
 228
 229 void setup_work_tree(void)
 230 {
 231         const char *work_tree, *git_dir;
 232         static int initialized = 0;
 233
 234         if (initialized)
 235                 return;
 236         work_tree = get_git_work_tree();
 237         git_dir = get_git_dir();
 238         if (!is_absolute_path(git_dir))
 239                 git_dir = make_absolute_path(git_dir);
 240         if (!work_tree || chdir(work_tree))
 241                 die("This operation must be run in a work tree");
 242         set_git_dir(make_relative_path(git_dir, work_tree));
 243         initialized = 1;
 244 }
 245
 246 static int check_repository_format_gently(int *nongit_ok)
 247 {
 248         git_config(check_repository_format_version, NULL);
 249         if (GIT_REPO_VERSION < repository_format_version) {
 250                 if (!nongit_ok)
 251                         die ("Expected git repo version <= %d, found %d",
 252                              GIT_REPO_VERSION, repository_format_version);
 253                 warning("Expected git repo version <= %d, found %d",
 254                         GIT_REPO_VERSION, repository_format_version);
 255                 warning("Please upgrade Git");
 256                 *nongit_ok = -1;
 257                 return -1;
 258         }
 259         return 0;
 260 }
 261
 262 /*
 263  * Try to read the location of the git directory from the .git file,
 264  * return path to git directory if found.
 265  */
 266 const char *read_gitfile_gently(const char *path)
 267 {
 268         char *buf;
 269         char *dir;
 270         const char *slash;
 271         struct stat st;
 272         int fd;
 273         size_t len;
 274
 275         if (stat(path, &st))
 276                 return NULL;
 277         if (!S_ISREG(st.st_mode))
 278                 return NULL;
 279         fd = open(path, O_RDONLY);
 280         if (fd < 0)
 281                 die_errno("Error opening '%s'", path);
 282         buf = xmalloc(st.st_size + 1);
 283         len = read_in_full(fd, buf, st.st_size);
 284         close(fd);
 285         if (len != st.st_size)
 286                 die("Error reading %s", path);
 287         buf[len] = '\0';
 288         if (prefixcmp(buf, "gitdir: "))
 289                 die("Invalid gitfile format: %s", path);
 290         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 291                 len--;
 292         if (len < 9)
 293                 die("No path in gitfile: %s", path);
 294         buf[len] = '\0';
 295         dir = buf + 8;
 296
 297         if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 298                 size_t pathlen = slash+1 - path;
 299                 size_t dirlen = pathlen + len - 8;
 300                 dir = xmalloc(dirlen + 1);
 301                 strncpy(dir, path, pathlen);
 302                 strncpy(dir + pathlen, buf + 8, len - 8);
 303                 dir[dirlen] = '\0';
 304                 free(buf);
 305                 buf = dir;
 306         }
 307
 308         if (!is_git_directory(dir))
 309                 die("Not a git repository: %s", dir);
 310         path = make_absolute_path(dir);
 311
 312         free(buf);
 313         return path;
 314 }
 315
 316 static const char *setup_explicit_git_dir(const char *gitdirenv,
 317                                 const char *work_tree_env, int *nongit_ok)
 318 {
 319         static char buffer[1024 + 1];
 320         const char *retval;
 321
 322         if (PATH_MAX - 40 < strlen(gitdirenv))
 323                 die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 324         if (!is_git_directory(gitdirenv)) {
 325                 if (nongit_ok) {
 326                         *nongit_ok = 1;
 327                         return NULL;
 328                 }
 329                 die("Not a git repository: '%s'", gitdirenv);
 330         }
 331         if (!work_tree_env) {
 332                 retval = set_work_tree(gitdirenv);
 333                 /* config may override worktree */
 334                 if (check_repository_format_gently(nongit_ok))
 335                         return NULL;
 336                 return retval;
 337         }
 338         if (check_repository_format_gently(nongit_ok))
 339                 return NULL;
 340         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 341                         get_git_work_tree());
 342         if (!retval || !*retval)
 343                 return NULL;
 344         set_git_dir(make_absolute_path(gitdirenv));
 345         if (chdir(work_tree_env) < 0)
 346                 die_errno ("Could not chdir to '%s'", work_tree_env);
 347         strcat(buffer, "/");
 348         return retval;
 349 }
 350
 351 static int cwd_contains_git_dir(const char **gitfile_dirp)
 352 {
 353         const char *gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 354         *gitfile_dirp = gitfile_dir;
 355         if (gitfile_dir) {
 356                 if (set_git_dir(gitfile_dir))
 357                         die("Repository setup failed");
 358                 return 1;
 359         }
 360         return is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT);
 361 }
 362
 363 static const char *setup_discovered_git_dir(const char *work_tree_env,
 364                 int offset, int len, char *cwd, int *nongit_ok)
 365 {
 366         int root_len;
 367
 368         inside_git_dir = 0;
 369         if (!work_tree_env)
 370                 inside_work_tree = 1;
 371         root_len = offset_1st_component(cwd);
 372         git_work_tree_cfg = xstrndup(cwd, offset > root_len ? offset : root_len);
 373         if (check_repository_format_gently(nongit_ok))
 374                 return NULL;
 375         if (offset == len)
 376                 return NULL;
 377
 378         /* Make "offset" point to past the '/', and add a '/' at the end */
 379         offset++;
 380         cwd[len++] = '/';
 381         cwd[len] = 0;
 382         return cwd + offset;
 383 }
 384
 385 static const char *setup_bare_git_dir(const char *work_tree_env,
 386                 int offset, int len, char *cwd, int *nongit_ok)
 387 {
 388         int root_len;
 389
 390         inside_git_dir = 1;
 391         if (!work_tree_env)
 392                 inside_work_tree = 0;
 393         if (offset != len) {
 394                 if (chdir(cwd))
 395                         die_errno("Cannot come back to cwd");
 396                 root_len = offset_1st_component(cwd);
 397                 cwd[offset > root_len ? offset : root_len] = '\0';
 398                 set_git_dir(cwd);
 399         } else
 400                 set_git_dir(".");
 401         check_repository_format_gently(nongit_ok);
 402         return NULL;
 403 }
 404
 405 static const char *setup_nongit(const char *cwd, int *nongit_ok)
 406 {
 407         if (!nongit_ok)
 408                 die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 409         if (chdir(cwd))
 410                 die_errno("Cannot come back to cwd");
 411         *nongit_ok = 1;
 412         return NULL;
 413 }
 414
 415 static dev_t get_device_or_die(const char *path, const char *prefix)
 416 {
 417         struct stat buf;
 418         if (stat(path, &buf))
 419                 die_errno("failed to stat '%s%s%s'",
 420                                 prefix ? prefix : "",
 421                                 prefix ? "/" : "", path);
 422         return buf.st_dev;
 423 }
 424
 425 /*
 426  * We cannot decide in this function whether we are in the work tree or
 427  * not, since the config can only be read _after_ this function was called.
 428  */
 429 static const char *setup_git_directory_gently_1(int *nongit_ok)
 430 {
 431         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 432         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 433         static char cwd[PATH_MAX+1];
 434         const char *gitdirenv;
 435         const char *gitfile_dir;
 436         int len, offset, ceil_offset;
 437         dev_t current_device = 0;
 438         int one_filesystem = 1;
 439
 440         /*
 441          * Let's assume that we are in a git repository.
 442          * If it turns out later that we are somewhere else, the value will be
 443          * updated accordingly.
 444          */
 445         if (nongit_ok)
 446                 *nongit_ok = 0;
 447
 448         /*
 449          * If GIT_DIR is set explicitly, we're not going
 450          * to do any discovery, but we still do repository
 451          * validation.
 452          */
 453         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 454         if (gitdirenv)
 455                 return setup_explicit_git_dir(gitdirenv, work_tree_env, nongit_ok);
 456
 457         if (!getcwd(cwd, sizeof(cwd)-1))
 458                 die_errno("Unable to read current working directory");
 459
 460         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 461         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 462                 ceil_offset = 1;
 463
 464         /*
 465          * Test in the following order (relative to the cwd):
 466          * - .git (file containing "gitdir: <path>")
 467          * - .git/
 468          * - ./ (bare)
 469          * - ../.git
 470          * - ../.git/
 471          * - ../ (bare)
 472          * - ../../.git/
 473          *   etc.
 474          */
 475         offset = len = strlen(cwd);
 476         one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 477         if (one_filesystem)
 478                 current_device = get_device_or_die(".", NULL);
 479         for (;;) {
 480                 if (cwd_contains_git_dir(&gitfile_dir))
 481                         return setup_discovered_git_dir(work_tree_env, offset,
 482                                                         len, cwd, nongit_ok);
 483                 if (is_git_directory("."))
 484                         return setup_bare_git_dir(work_tree_env, offset,
 485                                                         len, cwd, nongit_ok);
 486                 while (--offset > ceil_offset && cwd[offset] != '/');
 487                 if (offset <= ceil_offset)
 488                         return setup_nongit(cwd, nongit_ok);
 489                 if (one_filesystem) {
 490                         dev_t parent_device = get_device_or_die("..", cwd);
 491                         if (parent_device != current_device) {
 492                                 if (nongit_ok) {
 493                                         if (chdir(cwd))
 494                                                 die_errno("Cannot come back to cwd");
 495                                         *nongit_ok = 1;
 496                                         return NULL;
 497                                 }
 498                                 cwd[offset] = '\0';
 499                                 die("Not a git repository (or any parent up to mount parent %s)\n"
 500                                 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 501                         }
 502                 }
 503                 if (chdir("..")) {
 504                         cwd[offset] = '\0';
 505                         die_errno("Cannot change to '%s/..'", cwd);
 506                 }
 507         }
 508 }
 509
 510 const char *setup_git_directory_gently(int *nongit_ok)
 511 {
 512         const char *prefix;
 513
 514         prefix = setup_git_directory_gently_1(nongit_ok);
 515         if (startup_info)
 516                 startup_info->have_repository = !nongit_ok || !*nongit_ok;
 517         return prefix;
 518 }
 519
 520 int git_config_perm(const char *var, const char *value)
 521 {
 522         int i;
 523         char *endptr;
 524
 525         if (value == NULL)
 526                 return PERM_GROUP;
 527
 528         if (!strcmp(value, "umask"))
 529                 return PERM_UMASK;
 530         if (!strcmp(value, "group"))
 531                 return PERM_GROUP;
 532         if (!strcmp(value, "all") ||
 533             !strcmp(value, "world") ||
 534             !strcmp(value, "everybody"))
 535                 return PERM_EVERYBODY;
 536
 537         /* Parse octal numbers */
 538         i = strtol(value, &endptr, 8);
 539
 540         /* If not an octal number, maybe true/false? */
 541         if (*endptr != 0)
 542                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 543
 544         /*
 545          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 546          * a chmod value to restrict to.
 547          */
 548         switch (i) {
 549         case PERM_UMASK:               /* 0 */
 550                 return PERM_UMASK;
 551         case OLD_PERM_GROUP:           /* 1 */
 552                 return PERM_GROUP;
 553         case OLD_PERM_EVERYBODY:       /* 2 */
 554                 return PERM_EVERYBODY;
 555         }
 556
 557         /* A filemode value was given: 0xxx */
 558
 559         if ((i & 0600) != 0600)
 560                 die("Problem with core.sharedRepository filemode value "
 561                     "(0%.3o).\nThe owner of files must always have "
 562                     "read and write permissions.", i);
 563
 564         /*
 565          * Mask filemode value. Others can not get write permission.
 566          * x flags for directories are handled separately.
 567          */
 568         return -(i & 0666);
 569 }
 570
 571 int check_repository_format_version(const char *var, const char *value, void *cb)
 572 {
 573         if (strcmp(var, "core.repositoryformatversion") == 0)
 574                 repository_format_version = git_config_int(var, value);
 575         else if (strcmp(var, "core.sharedrepository") == 0)
 576                 shared_repository = git_config_perm(var, value);
 577         else if (strcmp(var, "core.bare") == 0) {
 578                 is_bare_repository_cfg = git_config_bool(var, value);
 579                 if (is_bare_repository_cfg == 1)
 580                         inside_work_tree = -1;
 581         } else if (strcmp(var, "core.worktree") == 0) {
 582                 if (!value)
 583                         return config_error_nonbool(var);
 584                 free(git_work_tree_cfg);
 585                 git_work_tree_cfg = xstrdup(value);
 586                 inside_work_tree = -1;
 587         }
 588         return 0;
 589 }
 590
 591 int check_repository_format(void)
 592 {
 593         return check_repository_format_gently(NULL);
 594 }
 595
 596 /*
 597  * Returns the "prefix", a path to the current working directory
 598  * relative to the work tree root, or NULL, if the current working
 599  * directory is not a strict subdirectory of the work tree root. The
 600  * prefix always ends with a '/' character.
 601  */
 602 const char *setup_git_directory(void)
 603 {
 604         const char *retval = setup_git_directory_gently(NULL);
 605
 606         /* If the work tree is not the default one, recompute prefix */
 607         if (inside_work_tree < 0) {
 608                 static char buffer[PATH_MAX + 1];
 609                 char *rel;
 610                 if (retval && chdir(retval))
 611                         die_errno ("Could not jump back into original cwd");
 612                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 613                 if (rel && *rel && chdir(get_git_work_tree()))
 614                         die_errno ("Could not jump to working directory");
 615                 return rel && *rel ? strcat(rel, "/") : NULL;
 616         }
 617
 618         return retval;
 619 }