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         strcpy(path, suspect);
 174         if (getenv(DB_ENVIRONMENT)) {
 175                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 176                         return 0;
 177         }
 178         else {
 179                 strcpy(path + len, "/objects");
 180                 if (access(path, X_OK))
 181                         return 0;
 182         }
 183
 184         strcpy(path + len, "/refs");
 185         if (access(path, X_OK))
 186                 return 0;
 187
 188         strcpy(path + len, "/HEAD");
 189         if (validate_headref(path))
 190                 return 0;
 191
 192         return 1;
 193 }
 194
 195 int is_inside_git_dir(void)
 196 {
 197         if (inside_git_dir < 0)
 198                 inside_git_dir = is_inside_dir(get_git_dir());
 199         return inside_git_dir;
 200 }
 201
 202 int is_inside_work_tree(void)
 203 {
 204         if (inside_work_tree < 0)
 205                 inside_work_tree = is_inside_dir(get_git_work_tree());
 206         return inside_work_tree;
 207 }
 208
 209 /*
 210  * set_work_tree() is only ever called if you set GIT_DIR explicitly.
 211  * The old behaviour (which we retain here) is to set the work tree root
 212  * to the cwd, unless overridden by the config, the command line, or
 213  * GIT_WORK_TREE.
 214  */
 215 static const char *set_work_tree(const char *dir)
 216 {
 217         char buffer[PATH_MAX + 1];
 218
 219         if (!getcwd(buffer, sizeof(buffer)))
 220                 die ("Could not get the current working directory");
 221         git_work_tree_cfg = xstrdup(buffer);
 222         inside_work_tree = 1;
 223
 224         return NULL;
 225 }
 226
 227 void setup_work_tree(void)
 228 {
 229         const char *work_tree, *git_dir;
 230         static int initialized = 0;
 231
 232         if (initialized)
 233                 return;
 234         work_tree = get_git_work_tree();
 235         git_dir = get_git_dir();
 236         if (!is_absolute_path(git_dir))
 237                 git_dir = make_absolute_path(git_dir);
 238         if (!work_tree || chdir(work_tree))
 239                 die("This operation must be run in a work tree");
 240         set_git_dir(make_relative_path(git_dir, work_tree));
 241         initialized = 1;
 242 }
 243
 244 static int check_repository_format_gently(int *nongit_ok)
 245 {
 246         git_config(check_repository_format_version, NULL);
 247         if (GIT_REPO_VERSION < repository_format_version) {
 248                 if (!nongit_ok)
 249                         die ("Expected git repo version <= %d, found %d",
 250                              GIT_REPO_VERSION, repository_format_version);
 251                 warning("Expected git repo version <= %d, found %d",
 252                         GIT_REPO_VERSION, repository_format_version);
 253                 warning("Please upgrade Git");
 254                 *nongit_ok = -1;
 255                 return -1;
 256         }
 257         return 0;
 258 }
 259
 260 /*
 261  * Try to read the location of the git directory from the .git file,
 262  * return path to git directory if found.
 263  */
 264 const char *read_gitfile_gently(const char *path)
 265 {
 266         char *buf;
 267         char *dir;
 268         const char *slash;
 269         struct stat st;
 270         int fd;
 271         size_t len;
 272
 273         if (stat(path, &st))
 274                 return NULL;
 275         if (!S_ISREG(st.st_mode))
 276                 return NULL;
 277         fd = open(path, O_RDONLY);
 278         if (fd < 0)
 279                 die_errno("Error opening '%s'", path);
 280         buf = xmalloc(st.st_size + 1);
 281         len = read_in_full(fd, buf, st.st_size);
 282         close(fd);
 283         if (len != st.st_size)
 284                 die("Error reading %s", path);
 285         buf[len] = '\0';
 286         if (prefixcmp(buf, "gitdir: "))
 287                 die("Invalid gitfile format: %s", path);
 288         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 289                 len--;
 290         if (len < 9)
 291                 die("No path in gitfile: %s", path);
 292         buf[len] = '\0';
 293         dir = buf + 8;
 294
 295         if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 296                 size_t pathlen = slash+1 - path;
 297                 size_t dirlen = pathlen + len - 8;
 298                 dir = xmalloc(dirlen + 1);
 299                 strncpy(dir, path, pathlen);
 300                 strncpy(dir + pathlen, buf + 8, len - 8);
 301                 dir[dirlen] = '\0';
 302                 free(buf);
 303                 buf = dir;
 304         }
 305
 306         if (!is_git_directory(dir))
 307                 die("Not a git repository: %s", dir);
 308         path = make_absolute_path(dir);
 309
 310         free(buf);
 311         return path;
 312 }
 313
 314 /*
 315  * We cannot decide in this function whether we are in the work tree or
 316  * not, since the config can only be read _after_ this function was called.
 317  */
 318 const char *setup_git_directory_gently(int *nongit_ok)
 319 {
 320         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 321         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 322         static char cwd[PATH_MAX+1];
 323         const char *gitdirenv;
 324         const char *gitfile_dir;
 325         int len, offset, ceil_offset, root_len;
 326         dev_t current_device = 0;
 327         int one_filesystem = 1;
 328         struct stat buf;
 329
 330         /*
 331          * Let's assume that we are in a git repository.
 332          * If it turns out later that we are somewhere else, the value will be
 333          * updated accordingly.
 334          */
 335         if (nongit_ok)
 336                 *nongit_ok = 0;
 337
 338         /*
 339          * If GIT_DIR is set explicitly, we're not going
 340          * to do any discovery, but we still do repository
 341          * validation.
 342          */
 343         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 344         if (gitdirenv) {
 345                 if (PATH_MAX - 40 < strlen(gitdirenv))
 346                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 347                 if (is_git_directory(gitdirenv)) {
 348                         static char buffer[1024 + 1];
 349                         const char *retval;
 350
 351                         if (!work_tree_env) {
 352                                 retval = set_work_tree(gitdirenv);
 353                                 /* config may override worktree */
 354                                 if (check_repository_format_gently(nongit_ok))
 355                                         return NULL;
 356                                 return retval;
 357                         }
 358                         if (check_repository_format_gently(nongit_ok))
 359                                 return NULL;
 360                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 361                                         get_git_work_tree());
 362                         if (!retval || !*retval)
 363                                 return NULL;
 364                         set_git_dir(make_absolute_path(gitdirenv));
 365                         if (chdir(work_tree_env) < 0)
 366                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 367                         strcat(buffer, "/");
 368                         return retval;
 369                 }
 370                 if (nongit_ok) {
 371                         *nongit_ok = 1;
 372                         return NULL;
 373                 }
 374                 die("Not a git repository: '%s'", gitdirenv);
 375         }
 376
 377         if (!getcwd(cwd, sizeof(cwd)-1))
 378                 die_errno("Unable to read current working directory");
 379
 380         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 381         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 382                 ceil_offset = 1;
 383
 384         /*
 385          * Test in the following order (relative to the cwd):
 386          * - .git (file containing "gitdir: <path>")
 387          * - .git/
 388          * - ./ (bare)
 389          * - ../.git
 390          * - ../.git/
 391          * - ../ (bare)
 392          * - ../../.git/
 393          *   etc.
 394          */
 395         offset = len = strlen(cwd);
 396         one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
 397         if (one_filesystem) {
 398                 if (stat(".", &buf))
 399                         die_errno("failed to stat '.'");
 400                 current_device = buf.st_dev;
 401         }
 402         for (;;) {
 403                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 404                 if (gitfile_dir) {
 405                         if (set_git_dir(gitfile_dir))
 406                                 die("Repository setup failed");
 407                         break;
 408                 }
 409                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 410                         break;
 411                 if (is_git_directory(".")) {
 412                         inside_git_dir = 1;
 413                         if (!work_tree_env)
 414                                 inside_work_tree = 0;
 415                         if (offset != len) {
 416                                 root_len = offset_1st_component(cwd);
 417                                 cwd[offset > root_len ? offset : root_len] = '\0';
 418                                 set_git_dir(cwd);
 419                         } else
 420                                 set_git_dir(".");
 421                         check_repository_format_gently(nongit_ok);
 422                         return NULL;
 423                 }
 424                 while (--offset > ceil_offset && cwd[offset] != '/');
 425                 if (offset <= ceil_offset) {
 426                         if (nongit_ok) {
 427                                 if (chdir(cwd))
 428                                         die_errno("Cannot come back to cwd");
 429                                 *nongit_ok = 1;
 430                                 return NULL;
 431                         }
 432                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 433                 }
 434                 if (one_filesystem) {
 435                         if (stat("..", &buf)) {
 436                                 cwd[offset] = '\0';
 437                                 die_errno("failed to stat '%s/..'", cwd);
 438                         }
 439                         if (buf.st_dev != current_device) {
 440                                 if (nongit_ok) {
 441                                         if (chdir(cwd))
 442                                                 die_errno("Cannot come back to cwd");
 443                                         *nongit_ok = 1;
 444                                         return NULL;
 445                                 }
 446                                 cwd[offset] = '\0';
 447                                 die("Not a git repository (or any parent up to mount parent %s)\n"
 448                                 "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
 449                         }
 450                 }
 451                 if (chdir("..")) {
 452                         cwd[offset] = '\0';
 453                         die_errno("Cannot change to '%s/..'", cwd);
 454                 }
 455         }
 456
 457         inside_git_dir = 0;
 458         if (!work_tree_env)
 459                 inside_work_tree = 1;
 460         root_len = offset_1st_component(cwd);
 461         git_work_tree_cfg = xstrndup(cwd, offset > root_len ? offset : root_len);
 462         if (check_repository_format_gently(nongit_ok))
 463                 return NULL;
 464         if (offset == len)
 465                 return NULL;
 466
 467         /* Make "offset" point to past the '/', and add a '/' at the end */
 468         offset++;
 469         cwd[len++] = '/';
 470         cwd[len] = 0;
 471         return cwd + offset;
 472 }
 473
 474 int git_config_perm(const char *var, const char *value)
 475 {
 476         int i;
 477         char *endptr;
 478
 479         if (value == NULL)
 480                 return PERM_GROUP;
 481
 482         if (!strcmp(value, "umask"))
 483                 return PERM_UMASK;
 484         if (!strcmp(value, "group"))
 485                 return PERM_GROUP;
 486         if (!strcmp(value, "all") ||
 487             !strcmp(value, "world") ||
 488             !strcmp(value, "everybody"))
 489                 return PERM_EVERYBODY;
 490
 491         /* Parse octal numbers */
 492         i = strtol(value, &endptr, 8);
 493
 494         /* If not an octal number, maybe true/false? */
 495         if (*endptr != 0)
 496                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 497
 498         /*
 499          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 500          * a chmod value to restrict to.
 501          */
 502         switch (i) {
 503         case PERM_UMASK:               /* 0 */
 504                 return PERM_UMASK;
 505         case OLD_PERM_GROUP:           /* 1 */
 506                 return PERM_GROUP;
 507         case OLD_PERM_EVERYBODY:       /* 2 */
 508                 return PERM_EVERYBODY;
 509         }
 510
 511         /* A filemode value was given: 0xxx */
 512
 513         if ((i & 0600) != 0600)
 514                 die("Problem with core.sharedRepository filemode value "
 515                     "(0%.3o).\nThe owner of files must always have "
 516                     "read and write permissions.", i);
 517
 518         /*
 519          * Mask filemode value. Others can not get write permission.
 520          * x flags for directories are handled separately.
 521          */
 522         return -(i & 0666);
 523 }
 524
 525 int check_repository_format_version(const char *var, const char *value, void *cb)
 526 {
 527         if (strcmp(var, "core.repositoryformatversion") == 0)
 528                 repository_format_version = git_config_int(var, value);
 529         else if (strcmp(var, "core.sharedrepository") == 0)
 530                 shared_repository = git_config_perm(var, value);
 531         else if (strcmp(var, "core.bare") == 0) {
 532                 is_bare_repository_cfg = git_config_bool(var, value);
 533                 if (is_bare_repository_cfg == 1)
 534                         inside_work_tree = -1;
 535         } else if (strcmp(var, "core.worktree") == 0) {
 536                 if (!value)
 537                         return config_error_nonbool(var);
 538                 free(git_work_tree_cfg);
 539                 git_work_tree_cfg = xstrdup(value);
 540                 inside_work_tree = -1;
 541         }
 542         return 0;
 543 }
 544
 545 int check_repository_format(void)
 546 {
 547         return check_repository_format_gently(NULL);
 548 }
 549
 550 /*
 551  * Returns the "prefix", a path to the current working directory
 552  * relative to the work tree root, or NULL, if the current working
 553  * directory is not a strict subdirectory of the work tree root. The
 554  * prefix always ends with a '/' character.
 555  */
 556 const char *setup_git_directory(void)
 557 {
 558         const char *retval = setup_git_directory_gently(NULL);
 559
 560         /* If the work tree is not the default one, recompute prefix */
 561         if (inside_work_tree < 0) {
 562                 static char buffer[PATH_MAX + 1];
 563                 char *rel;
 564                 if (retval && chdir(retval))
 565                         die_errno ("Could not jump back into original cwd");
 566                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 567                 if (rel && *rel && chdir(get_git_work_tree()))
 568                         die_errno ("Could not jump to working directory");
 569                 return rel && *rel ? strcat(rel, "/") : NULL;
 570         }
 571
 572         return retval;
 573 }