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                 const char *work_tree = get_git_work_tree();
  22                 size_t len = strlen(work_tree);
  23                 size_t total = strlen(sanitized) + 1;
  24                 if (strncmp(sanitized, work_tree, len) ||
  25                     (sanitized[len] != '\0' && sanitized[len] != '/')) {
  26                 error_out:
  27                         die("'%s' is outside repository", orig);
  28                 }
  29                 if (sanitized[len] == '/')
  30                         len++;
  31                 memmove(sanitized, sanitized + len, total - len);
  32         }
  33         return sanitized;
  34 }
  35
  36 /*
  37  * Unlike prefix_path, this should be used if the named file does
  38  * not have to interact with index entry; i.e. name of a random file
  39  * on the filesystem.
  40  */
  41 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
  42 {
  43         static char path[PATH_MAX];
  44 #ifndef WIN32
  45         if (!pfx || !*pfx || is_absolute_path(arg))
  46                 return arg;
  47         memcpy(path, pfx, pfx_len);
  48         strcpy(path + pfx_len, arg);
  49 #else
  50         char *p;
  51         /* don't add prefix to absolute paths, but still replace '\' by '/' */
  52         if (is_absolute_path(arg))
  53                 pfx_len = 0;
  54         else
  55                 memcpy(path, pfx, pfx_len);
  56         strcpy(path + pfx_len, arg);
  57         for (p = path + pfx_len; *p; p++)
  58                 if (*p == '\\')
  59                         *p = '/';
  60 #endif
  61         return path;
  62 }
  63
  64 /*
  65  * Verify a filename that we got as an argument for a pathspec
  66  * entry. Note that a filename that begins with "-" never verifies
  67  * as true, because even if such a filename were to exist, we want
  68  * it to be preceded by the "--" marker (or we want the user to
  69  * use a format like "./-filename")
  70  */
  71 void verify_filename(const char *prefix, const char *arg)
  72 {
  73         const char *name;
  74         struct stat st;
  75
  76         if (*arg == '-')
  77                 die("bad flag '%s' used after filename", arg);
  78         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  79         if (!lstat(name, &st))
  80                 return;
  81         if (errno == ENOENT)
  82                 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  83                     "Use '--' to separate paths from revisions", arg);
  84         die_errno("failed to stat '%s'", arg);
  85 }
  86
  87 /*
  88  * Opposite of the above: the command line did not have -- marker
  89  * and we parsed the arg as a refname.  It should not be interpretable
  90  * as a filename.
  91  */
  92 void verify_non_filename(const char *prefix, const char *arg)
  93 {
  94         const char *name;
  95         struct stat st;
  96
  97         if (!is_inside_work_tree() || is_inside_git_dir())
  98                 return;
  99         if (*arg == '-')
 100                 return; /* flag */
 101         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
 102         if (!lstat(name, &st))
 103                 die("ambiguous argument '%s': both revision and filename\n"
 104                     "Use '--' to separate filenames from revisions", arg);
 105         if (errno != ENOENT && errno != ENOTDIR)
 106                 die_errno("failed to stat '%s'", arg);
 107 }
 108
 109 const char **get_pathspec(const char *prefix, const char **pathspec)
 110 {
 111         const char *entry = *pathspec;
 112         const char **src, **dst;
 113         int prefixlen;
 114
 115         if (!prefix && !entry)
 116                 return NULL;
 117
 118         if (!entry) {
 119                 static const char *spec[2];
 120                 spec[0] = prefix;
 121                 spec[1] = NULL;
 122                 return spec;
 123         }
 124
 125         /* Otherwise we have to re-write the entries.. */
 126         src = pathspec;
 127         dst = pathspec;
 128         prefixlen = prefix ? strlen(prefix) : 0;
 129         while (*src) {
 130                 const char *p = prefix_path(prefix, prefixlen, *src);
 131                 *(dst++) = p;
 132                 src++;
 133         }
 134         *dst = NULL;
 135         if (!*pathspec)
 136                 return NULL;
 137         return pathspec;
 138 }
 139
 140 /*
 141  * Test if it looks like we're at a git directory.
 142  * We want to see:
 143  *
 144  *  - either an objects/ directory _or_ the proper
 145  *    GIT_OBJECT_DIRECTORY environment variable
 146  *  - a refs/ directory
 147  *  - either a HEAD symlink or a HEAD file that is formatted as
 148  *    a proper "ref:", or a regular file HEAD that has a properly
 149  *    formatted sha1 object name.
 150  */
 151 static int is_git_directory(const char *suspect)
 152 {
 153         char path[PATH_MAX];
 154         size_t len = strlen(suspect);
 155
 156         strcpy(path, suspect);
 157         if (getenv(DB_ENVIRONMENT)) {
 158                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 159                         return 0;
 160         }
 161         else {
 162                 strcpy(path + len, "/objects");
 163                 if (access(path, X_OK))
 164                         return 0;
 165         }
 166
 167         strcpy(path + len, "/refs");
 168         if (access(path, X_OK))
 169                 return 0;
 170
 171         strcpy(path + len, "/HEAD");
 172         if (validate_headref(path))
 173                 return 0;
 174
 175         return 1;
 176 }
 177
 178 int is_inside_git_dir(void)
 179 {
 180         if (inside_git_dir < 0)
 181                 inside_git_dir = is_inside_dir(get_git_dir());
 182         return inside_git_dir;
 183 }
 184
 185 int is_inside_work_tree(void)
 186 {
 187         if (inside_work_tree < 0)
 188                 inside_work_tree = is_inside_dir(get_git_work_tree());
 189         return inside_work_tree;
 190 }
 191
 192 /*
 193  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 194  * The old behaviour (which we retain here) is to set the work tree root
 195  * to the cwd, unless overridden by the config, the command line, or
 196  * GIT_WORK_TREE.
 197  */
 198 static const char *set_work_tree(const char *dir)
 199 {
 200         char buffer[PATH_MAX + 1];
 201
 202         if (!getcwd(buffer, sizeof(buffer)))
 203                 die ("Could not get the current working directory");
 204         git_work_tree_cfg = xstrdup(buffer);
 205         inside_work_tree = 1;
 206
 207         return NULL;
 208 }
 209
 210 void setup_work_tree(void)
 211 {
 212         const char *work_tree, *git_dir;
 213         static int initialized = 0;
 214
 215         if (initialized)
 216                 return;
 217         work_tree = get_git_work_tree();
 218         git_dir = get_git_dir();
 219         if (!is_absolute_path(git_dir))
 220                 git_dir = make_absolute_path(git_dir);
 221         if (!work_tree || chdir(work_tree))
 222                 die("This operation must be run in a work tree");
 223         set_git_dir(make_relative_path(git_dir, work_tree));
 224         initialized = 1;
 225 }
 226
 227 static int check_repository_format_gently(int *nongit_ok)
 228 {
 229         git_config(check_repository_format_version, NULL);
 230         if (GIT_REPO_VERSION < repository_format_version) {
 231                 if (!nongit_ok)
 232                         die ("Expected git repo version <= %d, found %d",
 233                              GIT_REPO_VERSION, repository_format_version);
 234                 warning("Expected git repo version <= %d, found %d",
 235                         GIT_REPO_VERSION, repository_format_version);
 236                 warning("Please upgrade Git");
 237                 *nongit_ok = -1;
 238                 return -1;
 239         }
 240         return 0;
 241 }
 242
 243 /*
 244  * Try to read the location of the git directory from the .git file,
 245  * return path to git directory if found.
 246  */
 247 const char *read_gitfile_gently(const char *path)
 248 {
 249         char *buf;
 250         struct stat st;
 251         int fd;
 252         size_t len;
 253
 254         if (stat(path, &st))
 255                 return NULL;
 256         if (!S_ISREG(st.st_mode))
 257                 return NULL;
 258         fd = open(path, O_RDONLY);
 259         if (fd < 0)
 260                 die_errno("Error opening '%s'", path);
 261         buf = xmalloc(st.st_size + 1);
 262         len = read_in_full(fd, buf, st.st_size);
 263         close(fd);
 264         if (len != st.st_size)
 265                 die("Error reading %s", path);
 266         buf[len] = '\0';
 267         if (prefixcmp(buf, "gitdir: "))
 268                 die("Invalid gitfile format: %s", path);
 269         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 270                 len--;
 271         if (len < 9)
 272                 die("No path in gitfile: %s", path);
 273         buf[len] = '\0';
 274         if (!is_git_directory(buf + 8))
 275                 die("Not a git repository: %s", buf + 8);
 276         path = make_absolute_path(buf + 8);
 277         free(buf);
 278         return path;
 279 }
 280
 281 /*
 282  * We cannot decide in this function whether we are in the work tree or
 283  * not, since the config can only be read _after_ this function was called.
 284  */
 285 const char *setup_git_directory_gently(int *nongit_ok)
 286 {
 287         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 288         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 289         static char cwd[PATH_MAX+1];
 290         const char *gitdirenv;
 291         const char *gitfile_dir;
 292         int len, offset, ceil_offset;
 293
 294         /*
 295          * Let's assume that we are in a git repository.
 296          * If it turns out later that we are somewhere else, the value will be
 297          * updated accordingly.
 298          */
 299         if (nongit_ok)
 300                 *nongit_ok = 0;
 301
 302         /*
 303          * If GIT_DIR is set explicitly, we're not going
 304          * to do any discovery, but we still do repository
 305          * validation.
 306          */
 307         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 308         if (gitdirenv) {
 309                 if (PATH_MAX - 40 < strlen(gitdirenv))
 310                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 311                 if (is_git_directory(gitdirenv)) {
 312                         static char buffer[1024 + 1];
 313                         const char *retval;
 314
 315                         if (!work_tree_env) {
 316                                 retval = set_work_tree(gitdirenv);
 317                                 /* config may override worktree */
 318                                 if (check_repository_format_gently(nongit_ok))
 319                                         return NULL;
 320                                 return retval;
 321                         }
 322                         if (check_repository_format_gently(nongit_ok))
 323                                 return NULL;
 324                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 325                                         get_git_work_tree());
 326                         if (!retval || !*retval)
 327                                 return NULL;
 328                         set_git_dir(make_absolute_path(gitdirenv));
 329                         if (chdir(work_tree_env) < 0)
 330                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 331                         strcat(buffer, "/");
 332                         return retval;
 333                 }
 334                 if (nongit_ok) {
 335                         *nongit_ok = 1;
 336                         return NULL;
 337                 }
 338                 die("Not a git repository: '%s'", gitdirenv);
 339         }
 340
 341         if (!getcwd(cwd, sizeof(cwd)-1))
 342                 die_errno("Unable to read current working directory");
 343
 344         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 345         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 346                 ceil_offset = 1;
 347
 348         /*
 349          * Test in the following order (relative to the cwd):
 350          * - .git (file containing "gitdir: <path>")
 351          * - .git/
 352          * - ./ (bare)
 353          * - ../.git
 354          * - ../.git/
 355          * - ../ (bare)
 356          * - ../../.git/
 357          *   etc.
 358          */
 359         offset = len = strlen(cwd);
 360         for (;;) {
 361                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 362                 if (gitfile_dir) {
 363                         if (set_git_dir(gitfile_dir))
 364                                 die("Repository setup failed");
 365                         break;
 366                 }
 367                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 368                         break;
 369                 if (is_git_directory(".")) {
 370                         inside_git_dir = 1;
 371                         if (!work_tree_env)
 372                                 inside_work_tree = 0;
 373                         if (offset != len) {
 374                                 cwd[offset] = '\0';
 375                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 376                         } else
 377                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 378                         check_repository_format_gently(nongit_ok);
 379                         return NULL;
 380                 }
 381                 while (--offset > ceil_offset && cwd[offset] != '/');
 382                 if (offset <= ceil_offset) {
 383                         if (nongit_ok) {
 384                                 if (chdir(cwd))
 385                                         die_errno("Cannot come back to cwd");
 386                                 *nongit_ok = 1;
 387                                 return NULL;
 388                         }
 389                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 390                 }
 391                 if (chdir(".."))
 392                         die_errno("Cannot change to '%s/..'", cwd);
 393         }
 394
 395         inside_git_dir = 0;
 396         if (!work_tree_env)
 397                 inside_work_tree = 1;
 398         git_work_tree_cfg = xstrndup(cwd, offset);
 399         if (check_repository_format_gently(nongit_ok))
 400                 return NULL;
 401         if (offset == len)
 402                 return NULL;
 403
 404         /* Make "offset" point to past the '/', and add a '/' at the end */
 405         offset++;
 406         cwd[len++] = '/';
 407         cwd[len] = 0;
 408         return cwd + offset;
 409 }
 410
 411 int git_config_perm(const char *var, const char *value)
 412 {
 413         int i;
 414         char *endptr;
 415
 416         if (value == NULL)
 417                 return PERM_GROUP;
 418
 419         if (!strcmp(value, "umask"))
 420                 return PERM_UMASK;
 421         if (!strcmp(value, "group"))
 422                 return PERM_GROUP;
 423         if (!strcmp(value, "all") ||
 424             !strcmp(value, "world") ||
 425             !strcmp(value, "everybody"))
 426                 return PERM_EVERYBODY;
 427
 428         /* Parse octal numbers */
 429         i = strtol(value, &endptr, 8);
 430
 431         /* If not an octal number, maybe true/false? */
 432         if (*endptr != 0)
 433                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 434
 435         /*
 436          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 437          * a chmod value to restrict to.
 438          */
 439         switch (i) {
 440         case PERM_UMASK:               /* 0 */
 441                 return PERM_UMASK;
 442         case OLD_PERM_GROUP:           /* 1 */
 443                 return PERM_GROUP;
 444         case OLD_PERM_EVERYBODY:       /* 2 */
 445                 return PERM_EVERYBODY;
 446         }
 447
 448         /* A filemode value was given: 0xxx */
 449
 450         if ((i & 0600) != 0600)
 451                 die("Problem with core.sharedRepository filemode value "
 452                     "(0%.3o).\nThe owner of files must always have "
 453                     "read and write permissions.", i);
 454
 455         /*
 456          * Mask filemode value. Others can not get write permission.
 457          * x flags for directories are handled separately.
 458          */
 459         return -(i & 0666);
 460 }
 461
 462 int check_repository_format_version(const char *var, const char *value, void *cb)
 463 {
 464         if (strcmp(var, "core.repositoryformatversion") == 0)
 465                 repository_format_version = git_config_int(var, value);
 466         else if (strcmp(var, "core.sharedrepository") == 0)
 467                 shared_repository = git_config_perm(var, value);
 468         else if (strcmp(var, "core.bare") == 0) {
 469                 is_bare_repository_cfg = git_config_bool(var, value);
 470                 if (is_bare_repository_cfg == 1)
 471                         inside_work_tree = -1;
 472         } else if (strcmp(var, "core.worktree") == 0) {
 473                 if (!value)
 474                         return config_error_nonbool(var);
 475                 free(git_work_tree_cfg);
 476                 git_work_tree_cfg = xstrdup(value);
 477                 inside_work_tree = -1;
 478         }
 479         return 0;
 480 }
 481
 482 int check_repository_format(void)
 483 {
 484         return check_repository_format_gently(NULL);
 485 }
 486
 487 const char *setup_git_directory(void)
 488 {
 489         const char *retval = setup_git_directory_gently(NULL);
 490
 491         /* If the work tree is not the default one, recompute prefix */
 492         if (inside_work_tree < 0) {
 493                 static char buffer[PATH_MAX + 1];
 494                 char *rel;
 495                 if (retval && chdir(retval))
 496                         die_errno ("Could not jump back into original cwd");
 497                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 498                 if (rel && *rel && chdir(get_git_work_tree()))
 499                         die_errno ("Could not jump to working directory");
 500                 return rel && *rel ? strcat(rel, "/") : NULL;
 501         }
 502
 503         return retval;
 504 }