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 /*
 317  * We cannot decide in this function whether we are in the work tree or
 318  * not, since the config can only be read _after_ this function was called.
 319  */
 320 const char *setup_git_directory_gently(int *nongit_ok)
 321 {
 322         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 323         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 324         static char cwd[PATH_MAX+1];
 325         const char *gitdirenv;
 326         const char *gitfile_dir;
 327         int len, offset, ceil_offset, root_len;
 328         dev_t current_device = 0;
 329         int one_filesystem = 1;
 330         struct stat buf;
 331
 332         /*
 333          * Let's assume that we are in a git repository.
 334          * If it turns out later that we are somewhere else, the value will be
 335          * updated accordingly.
 336          */
 337         if (nongit_ok)
 338                 *nongit_ok = 0;
 339
 340         /*
 341          * If GIT_DIR is set explicitly, we're not going
 342          * to do any discovery, but we still do repository
 343          * validation.
 344          */
 345         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 346         if (gitdirenv) {
 347                 if (PATH_MAX - 40 < strlen(gitdirenv))
 348                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 349                 if (is_git_directory(gitdirenv)) {
 350                         static char buffer[1024 + 1];
 351                         const char *retval;
 352
 353                         if (!work_tree_env) {
 354                                 retval = set_work_tree(gitdirenv);
 355                                 /* config may override worktree */
 356                                 if (check_repository_format_gently(nongit_ok))
 357                                         return NULL;
 358                                 return retval;
 359                         }
 360                         if (check_repository_format_gently(nongit_ok))
 361                                 return NULL;
 362                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 363                                         get_git_work_tree());
 364                         if (!retval || !*retval)
 365                                 return NULL;
 366                         set_git_dir(make_absolute_path(gitdirenv));
 367                         if (chdir(work_tree_env) < 0)
 368                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 369                         strcat(buffer, "/");
 370                         return retval;
 371                 }
 372                 if (nongit_ok) {
 373                         *nongit_ok = 1;
 374                         return NULL;
 375                 }
 376                 die("Not a git repository: '%s'", gitdirenv);
 377         }
 378
 379         if (!getcwd(cwd, sizeof(cwd)-1))
 380                 die_errno("Unable to read current working directory");
 381
 382         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 383         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 384                 ceil_offset = 1;
 385
 386         /*
 387          * Test in the following order (relative to the cwd):
 388          * - .git (file containing "gitdir: <path>")
 389          * - .git/
 390          * - ./ (bare)
 391          * - ../.git
 392          * - ../.git/
 393          * - ../ (bare)
 394          * - ../../.git/
 395          *   etc.
 396          */
 397         offset = len = strlen(cwd);
 398         one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 399         if (one_filesystem) {
 400                 if (stat(".", &buf))
 401                         die_errno("failed to stat '.'");
 402                 current_device = buf.st_dev;
 403         }
 404         for (;;) {
 405                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 406                 if (gitfile_dir) {
 407                         if (set_git_dir(gitfile_dir))
 408                                 die("Repository setup failed");
 409                         break;
 410                 }
 411                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 412                         break;
 413                 if (is_git_directory(".")) {
 414                         inside_git_dir = 1;
 415                         if (!work_tree_env)
 416                                 inside_work_tree = 0;
 417                         if (offset != len) {
 418                                 root_len = offset_1st_component(cwd);
 419                                 cwd[offset > root_len ? offset : root_len] = '\0';
 420                                 set_git_dir(cwd);
 421                         } else
 422                                 set_git_dir(".");
 423                         check_repository_format_gently(nongit_ok);
 424                         return NULL;
 425                 }
 426                 while (--offset > ceil_offset && cwd[offset] != '/');
 427                 if (offset <= ceil_offset) {
 428                         if (nongit_ok) {
 429                                 if (chdir(cwd))
 430                                         die_errno("Cannot come back to cwd");
 431                                 *nongit_ok = 1;
 432                                 return NULL;
 433                         }
 434                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 435                 }
 436                 if (one_filesystem) {
 437                         if (stat("..", &buf)) {
 438                                 cwd[offset] = '\0';
 439                                 die_errno("failed to stat '%s/..'", cwd);
 440                         }
 441                         if (buf.st_dev != current_device) {
 442                                 if (nongit_ok) {
 443                                         if (chdir(cwd))
 444                                                 die_errno("Cannot come back to cwd");
 445                                         *nongit_ok = 1;
 446                                         return NULL;
 447                                 }
 448                                 cwd[offset] = '\0';
 449                                 die("Not a git repository (or any parent up to mount parent %s)\n"
 450                                 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 451                         }
 452                 }
 453                 if (chdir("..")) {
 454                         cwd[offset] = '\0';
 455                         die_errno("Cannot change to '%s/..'", cwd);
 456                 }
 457         }
 458
 459         inside_git_dir = 0;
 460         if (!work_tree_env)
 461                 inside_work_tree = 1;
 462         root_len = offset_1st_component(cwd);
 463         git_work_tree_cfg = xstrndup(cwd, offset > root_len ? offset : root_len);
 464         if (check_repository_format_gently(nongit_ok))
 465                 return NULL;
 466         if (offset == len)
 467                 return NULL;
 468
 469         /* Make "offset" point to past the '/', and add a '/' at the end */
 470         offset++;
 471         cwd[len++] = '/';
 472         cwd[len] = 0;
 473         return cwd + offset;
 474 }
 475
 476 int git_config_perm(const char *var, const char *value)
 477 {
 478         int i;
 479         char *endptr;
 480
 481         if (value == NULL)
 482                 return PERM_GROUP;
 483
 484         if (!strcmp(value, "umask"))
 485                 return PERM_UMASK;
 486         if (!strcmp(value, "group"))
 487                 return PERM_GROUP;
 488         if (!strcmp(value, "all") ||
 489             !strcmp(value, "world") ||
 490             !strcmp(value, "everybody"))
 491                 return PERM_EVERYBODY;
 492
 493         /* Parse octal numbers */
 494         i = strtol(value, &endptr, 8);
 495
 496         /* If not an octal number, maybe true/false? */
 497         if (*endptr != 0)
 498                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 499
 500         /*
 501          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 502          * a chmod value to restrict to.
 503          */
 504         switch (i) {
 505         case PERM_UMASK:               /* 0 */
 506                 return PERM_UMASK;
 507         case OLD_PERM_GROUP:           /* 1 */
 508                 return PERM_GROUP;
 509         case OLD_PERM_EVERYBODY:       /* 2 */
 510                 return PERM_EVERYBODY;
 511         }
 512
 513         /* A filemode value was given: 0xxx */
 514
 515         if ((i & 0600) != 0600)
 516                 die("Problem with core.sharedRepository filemode value "
 517                     "(0%.3o).\nThe owner of files must always have "
 518                     "read and write permissions.", i);
 519
 520         /*
 521          * Mask filemode value. Others can not get write permission.
 522          * x flags for directories are handled separately.
 523          */
 524         return -(i & 0666);
 525 }
 526
 527 int check_repository_format_version(const char *var, const char *value, void *cb)
 528 {
 529         if (strcmp(var, "core.repositoryformatversion") == 0)
 530                 repository_format_version = git_config_int(var, value);
 531         else if (strcmp(var, "core.sharedrepository") == 0)
 532                 shared_repository = git_config_perm(var, value);
 533         else if (strcmp(var, "core.bare") == 0) {
 534                 is_bare_repository_cfg = git_config_bool(var, value);
 535                 if (is_bare_repository_cfg == 1)
 536                         inside_work_tree = -1;
 537         } else if (strcmp(var, "core.worktree") == 0) {
 538                 if (!value)
 539                         return config_error_nonbool(var);
 540                 free(git_work_tree_cfg);
 541                 git_work_tree_cfg = xstrdup(value);
 542                 inside_work_tree = -1;
 543         }
 544         return 0;
 545 }
 546
 547 int check_repository_format(void)
 548 {
 549         return check_repository_format_gently(NULL);
 550 }
 551
 552 /*
 553  * Returns the "prefix", a path to the current working directory
 554  * relative to the work tree root, or NULL, if the current working
 555  * directory is not a strict subdirectory of the work tree root. The
 556  * prefix always ends with a '/' character.
 557  */
 558 const char *setup_git_directory(void)
 559 {
 560         const char *retval = setup_git_directory_gently(NULL);
 561
 562         /* If the work tree is not the default one, recompute prefix */
 563         if (inside_work_tree < 0) {
 564                 static char buffer[PATH_MAX + 1];
 565                 char *rel;
 566                 if (retval && chdir(retval))
 567                         die_errno ("Could not jump back into original cwd");
 568                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 569                 if (rel && *rel && chdir(get_git_work_tree()))
 570                         die_errno ("Could not jump to working directory");
 571                 return rel && *rel ? strcat(rel, "/") : NULL;
 572         }
 573
 574         return retval;
 575 }