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 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                 total = strlen(sanitized) + 1;
  27                 if (strncmp(sanitized, work_tree, len) ||
  28                     (sanitized[len] != '\0' && sanitized[len] != '/')) {
  29                 error_out:
  30                         die("'%s' is outside repository", orig);
  31                 }
  32                 if (sanitized[len] == '/')
  33                         len++;
  34                 memmove(sanitized, sanitized + len, total - len);
  35         }
  36         return sanitized;
  37 }
  38
  39 /*
  40  * Unlike prefix_path, this should be used if the named file does
  41  * not have to interact with index entry; i.e. name of a random file
  42  * on the filesystem.
  43  */
  44 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
  45 {
  46         static char path[PATH_MAX];
  47 #ifndef WIN32
  48         if (!pfx || !*pfx || is_absolute_path(arg))
  49                 return arg;
  50         memcpy(path, pfx, pfx_len);
  51         strcpy(path + pfx_len, arg);
  52 #else
  53         char *p;
  54         /* don't add prefix to absolute paths, but still replace '\' by '/' */
  55         if (is_absolute_path(arg))
  56                 pfx_len = 0;
  57         else
  58                 memcpy(path, pfx, pfx_len);
  59         strcpy(path + pfx_len, arg);
  60         for (p = path + pfx_len; *p; p++)
  61                 if (*p == '\\')
  62                         *p = '/';
  63 #endif
  64         return path;
  65 }
  66
  67 /*
  68  * Verify a filename that we got as an argument for a pathspec
  69  * entry. Note that a filename that begins with "-" never verifies
  70  * as true, because even if such a filename were to exist, we want
  71  * it to be preceded by the "--" marker (or we want the user to
  72  * use a format like "./-filename")
  73  */
  74 void verify_filename(const char *prefix, const char *arg)
  75 {
  76         const char *name;
  77         struct stat st;
  78
  79         if (*arg == '-')
  80                 die("bad flag '%s' used after filename", arg);
  81         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  82         if (!lstat(name, &st))
  83                 return;
  84         if (errno == ENOENT)
  85                 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  86                     "Use '--' to separate paths from revisions", arg);
  87         die_errno("failed to stat '%s'", arg);
  88 }
  89
  90 /*
  91  * Opposite of the above: the command line did not have -- marker
  92  * and we parsed the arg as a refname.  It should not be interpretable
  93  * as a filename.
  94  */
  95 void verify_non_filename(const char *prefix, const char *arg)
  96 {
  97         const char *name;
  98         struct stat st;
  99
 100         if (!is_inside_work_tree() || is_inside_git_dir())
 101                 return;
 102         if (*arg == '-')
 103                 return; /* flag */
 104         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
 105         if (!lstat(name, &st))
 106                 die("ambiguous argument '%s': both revision and filename\n"
 107                     "Use '--' to separate filenames from revisions", arg);
 108         if (errno != ENOENT && errno != ENOTDIR)
 109                 die_errno("failed to stat '%s'", arg);
 110 }
 111
 112 const char **get_pathspec(const char *prefix, const char **pathspec)
 113 {
 114         const char *entry = *pathspec;
 115         const char **src, **dst;
 116         int prefixlen;
 117
 118         if (!prefix && !entry)
 119                 return NULL;
 120
 121         if (!entry) {
 122                 static const char *spec[2];
 123                 spec[0] = prefix;
 124                 spec[1] = NULL;
 125                 return spec;
 126         }
 127
 128         /* Otherwise we have to re-write the entries.. */
 129         src = pathspec;
 130         dst = pathspec;
 131         prefixlen = prefix ? strlen(prefix) : 0;
 132         while (*src) {
 133                 const char *p = prefix_path(prefix, prefixlen, *src);
 134                 *(dst++) = p;
 135                 src++;
 136         }
 137         *dst = NULL;
 138         if (!*pathspec)
 139                 return NULL;
 140         return pathspec;
 141 }
 142
 143 /*
 144  * Test if it looks like we're at a git directory.
 145  * We want to see:
 146  *
 147  *  - either an objects/ directory _or_ the proper
 148  *    GIT_OBJECT_DIRECTORY environment variable
 149  *  - a refs/ directory
 150  *  - either a HEAD symlink or a HEAD file that is formatted as
 151  *    a proper "ref:", or a regular file HEAD that has a properly
 152  *    formatted sha1 object name.
 153  */
 154 static int is_git_directory(const char *suspect)
 155 {
 156         char path[PATH_MAX];
 157         size_t len = strlen(suspect);
 158
 159         if (PATH_MAX <= len + strlen("/objects"))
 160                 die("Too long path: %.*s", 60, suspect);
 161         strcpy(path, suspect);
 162         if (getenv(DB_ENVIRONMENT)) {
 163                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 164                         return 0;
 165         }
 166         else {
 167                 strcpy(path + len, "/objects");
 168                 if (access(path, X_OK))
 169                         return 0;
 170         }
 171
 172         strcpy(path + len, "/refs");
 173         if (access(path, X_OK))
 174                 return 0;
 175
 176         strcpy(path + len, "/HEAD");
 177         if (validate_headref(path))
 178                 return 0;
 179
 180         return 1;
 181 }
 182
 183 int is_inside_git_dir(void)
 184 {
 185         if (inside_git_dir < 0)
 186                 inside_git_dir = is_inside_dir(get_git_dir());
 187         return inside_git_dir;
 188 }
 189
 190 int is_inside_work_tree(void)
 191 {
 192         if (inside_work_tree < 0)
 193                 inside_work_tree = is_inside_dir(get_git_work_tree());
 194         return inside_work_tree;
 195 }
 196
 197 /*
 198  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 199  * The old behaviour (which we retain here) is to set the work tree root
 200  * to the cwd, unless overridden by the config, the command line, or
 201  * GIT_WORK_TREE.
 202  */
 203 static const char *set_work_tree(const char *dir)
 204 {
 205         char buffer[PATH_MAX + 1];
 206
 207         if (!getcwd(buffer, sizeof(buffer)))
 208                 die ("Could not get the current working directory");
 209         git_work_tree_cfg = xstrdup(buffer);
 210         inside_work_tree = 1;
 211
 212         return NULL;
 213 }
 214
 215 void setup_work_tree(void)
 216 {
 217         const char *work_tree, *git_dir;
 218         static int initialized = 0;
 219
 220         if (initialized)
 221                 return;
 222         work_tree = get_git_work_tree();
 223         git_dir = get_git_dir();
 224         if (!is_absolute_path(git_dir))
 225                 git_dir = make_absolute_path(git_dir);
 226         if (!work_tree || chdir(work_tree))
 227                 die("This operation must be run in a work tree");
 228         set_git_dir(make_relative_path(git_dir, work_tree));
 229         initialized = 1;
 230 }
 231
 232 static int check_repository_format_gently(int *nongit_ok)
 233 {
 234         git_config(check_repository_format_version, NULL);
 235         if (GIT_REPO_VERSION < repository_format_version) {
 236                 if (!nongit_ok)
 237                         die ("Expected git repo version <= %d, found %d",
 238                              GIT_REPO_VERSION, repository_format_version);
 239                 warning("Expected git repo version <= %d, found %d",
 240                         GIT_REPO_VERSION, repository_format_version);
 241                 warning("Please upgrade Git");
 242                 *nongit_ok = -1;
 243                 return -1;
 244         }
 245         return 0;
 246 }
 247
 248 /*
 249  * Try to read the location of the git directory from the .git file,
 250  * return path to git directory if found.
 251  */
 252 const char *read_gitfile_gently(const char *path)
 253 {
 254         char *buf;
 255         struct stat st;
 256         int fd;
 257         size_t len;
 258
 259         if (stat(path, &st))
 260                 return NULL;
 261         if (!S_ISREG(st.st_mode))
 262                 return NULL;
 263         fd = open(path, O_RDONLY);
 264         if (fd < 0)
 265                 die_errno("Error opening '%s'", path);
 266         buf = xmalloc(st.st_size + 1);
 267         len = read_in_full(fd, buf, st.st_size);
 268         close(fd);
 269         if (len != st.st_size)
 270                 die("Error reading %s", path);
 271         buf[len] = '\0';
 272         if (prefixcmp(buf, "gitdir: "))
 273                 die("Invalid gitfile format: %s", path);
 274         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 275                 len--;
 276         if (len < 9)
 277                 die("No path in gitfile: %s", path);
 278         buf[len] = '\0';
 279         if (!is_git_directory(buf + 8))
 280                 die("Not a git repository: %s", buf + 8);
 281         path = make_absolute_path(buf + 8);
 282         free(buf);
 283         return path;
 284 }
 285
 286 /*
 287  * We cannot decide in this function whether we are in the work tree or
 288  * not, since the config can only be read _after_ this function was called.
 289  */
 290 const char *setup_git_directory_gently(int *nongit_ok)
 291 {
 292         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 293         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 294         static char cwd[PATH_MAX+1];
 295         const char *gitdirenv;
 296         const char *gitfile_dir;
 297         int len, offset, ceil_offset;
 298
 299         /*
 300          * Let's assume that we are in a git repository.
 301          * If it turns out later that we are somewhere else, the value will be
 302          * updated accordingly.
 303          */
 304         if (nongit_ok)
 305                 *nongit_ok = 0;
 306
 307         /*
 308          * If GIT_DIR is set explicitly, we're not going
 309          * to do any discovery, but we still do repository
 310          * validation.
 311          */
 312         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 313         if (gitdirenv) {
 314                 if (PATH_MAX - 40 < strlen(gitdirenv))
 315                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 316                 if (is_git_directory(gitdirenv)) {
 317                         static char buffer[1024 + 1];
 318                         const char *retval;
 319
 320                         if (!work_tree_env) {
 321                                 retval = set_work_tree(gitdirenv);
 322                                 /* config may override worktree */
 323                                 if (check_repository_format_gently(nongit_ok))
 324                                         return NULL;
 325                                 return retval;
 326                         }
 327                         if (check_repository_format_gently(nongit_ok))
 328                                 return NULL;
 329                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 330                                         get_git_work_tree());
 331                         if (!retval || !*retval)
 332                                 return NULL;
 333                         set_git_dir(make_absolute_path(gitdirenv));
 334                         if (chdir(work_tree_env) < 0)
 335                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 336                         strcat(buffer, "/");
 337                         return retval;
 338                 }
 339                 if (nongit_ok) {
 340                         *nongit_ok = 1;
 341                         return NULL;
 342                 }
 343                 die("Not a git repository: '%s'", gitdirenv);
 344         }
 345
 346         if (!getcwd(cwd, sizeof(cwd)-1))
 347                 die_errno("Unable to read current working directory");
 348
 349         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 350         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 351                 ceil_offset = 1;
 352
 353         /*
 354          * Test in the following order (relative to the cwd):
 355          * - .git (file containing "gitdir: <path>")
 356          * - .git/
 357          * - ./ (bare)
 358          * - ../.git
 359          * - ../.git/
 360          * - ../ (bare)
 361          * - ../../.git/
 362          *   etc.
 363          */
 364         offset = len = strlen(cwd);
 365         for (;;) {
 366                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 367                 if (gitfile_dir) {
 368                         if (set_git_dir(gitfile_dir))
 369                                 die("Repository setup failed");
 370                         break;
 371                 }
 372                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 373                         break;
 374                 if (is_git_directory(".")) {
 375                         inside_git_dir = 1;
 376                         if (!work_tree_env)
 377                                 inside_work_tree = 0;
 378                         if (offset != len) {
 379                                 cwd[offset] = '\0';
 380                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 381                         } else
 382                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 383                         check_repository_format_gently(nongit_ok);
 384                         return NULL;
 385                 }
 386                 while (--offset > ceil_offset && cwd[offset] != '/');
 387                 if (offset <= ceil_offset) {
 388                         if (nongit_ok) {
 389                                 if (chdir(cwd))
 390                                         die_errno("Cannot come back to cwd");
 391                                 *nongit_ok = 1;
 392                                 return NULL;
 393                         }
 394                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 395                 }
 396                 if (chdir(".."))
 397                         die_errno("Cannot change to '%s/..'", cwd);
 398         }
 399
 400         inside_git_dir = 0;
 401         if (!work_tree_env)
 402                 inside_work_tree = 1;
 403         git_work_tree_cfg = xstrndup(cwd, offset);
 404         if (check_repository_format_gently(nongit_ok))
 405                 return NULL;
 406         if (offset == len)
 407                 return NULL;
 408
 409         /* Make "offset" point to past the '/', and add a '/' at the end */
 410         offset++;
 411         cwd[len++] = '/';
 412         cwd[len] = 0;
 413         return cwd + offset;
 414 }
 415
 416 int git_config_perm(const char *var, const char *value)
 417 {
 418         int i;
 419         char *endptr;
 420
 421         if (value == NULL)
 422                 return PERM_GROUP;
 423
 424         if (!strcmp(value, "umask"))
 425                 return PERM_UMASK;
 426         if (!strcmp(value, "group"))
 427                 return PERM_GROUP;
 428         if (!strcmp(value, "all") ||
 429             !strcmp(value, "world") ||
 430             !strcmp(value, "everybody"))
 431                 return PERM_EVERYBODY;
 432
 433         /* Parse octal numbers */
 434         i = strtol(value, &endptr, 8);
 435
 436         /* If not an octal number, maybe true/false? */
 437         if (*endptr != 0)
 438                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 439
 440         /*
 441          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 442          * a chmod value to restrict to.
 443          */
 444         switch (i) {
 445         case PERM_UMASK:               /* 0 */
 446                 return PERM_UMASK;
 447         case OLD_PERM_GROUP:           /* 1 */
 448                 return PERM_GROUP;
 449         case OLD_PERM_EVERYBODY:       /* 2 */
 450                 return PERM_EVERYBODY;
 451         }
 452
 453         /* A filemode value was given: 0xxx */
 454
 455         if ((i & 0600) != 0600)
 456                 die("Problem with core.sharedRepository filemode value "
 457                     "(0%.3o).\nThe owner of files must always have "
 458                     "read and write permissions.", i);
 459
 460         /*
 461          * Mask filemode value. Others can not get write permission.
 462          * x flags for directories are handled separately.
 463          */
 464         return -(i & 0666);
 465 }
 466
 467 int check_repository_format_version(const char *var, const char *value, void *cb)
 468 {
 469         if (strcmp(var, "core.repositoryformatversion") == 0)
 470                 repository_format_version = git_config_int(var, value);
 471         else if (strcmp(var, "core.sharedrepository") == 0)
 472                 shared_repository = git_config_perm(var, value);
 473         else if (strcmp(var, "core.bare") == 0) {
 474                 is_bare_repository_cfg = git_config_bool(var, value);
 475                 if (is_bare_repository_cfg == 1)
 476                         inside_work_tree = -1;
 477         } else if (strcmp(var, "core.worktree") == 0) {
 478                 if (!value)
 479                         return config_error_nonbool(var);
 480                 free(git_work_tree_cfg);
 481                 git_work_tree_cfg = xstrdup(value);
 482                 inside_work_tree = -1;
 483         }
 484         return 0;
 485 }
 486
 487 int check_repository_format(void)
 488 {
 489         return check_repository_format_gently(NULL);
 490 }
 491
 492 const char *setup_git_directory(void)
 493 {
 494         const char *retval = setup_git_directory_gently(NULL);
 495
 496         /* If the work tree is not the default one, recompute prefix */
 497         if (inside_work_tree < 0) {
 498                 static char buffer[PATH_MAX + 1];
 499                 char *rel;
 500                 if (retval && chdir(retval))
 501                         die_errno ("Could not jump back into original cwd");
 502                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 503                 if (rel && *rel && chdir(get_git_work_tree()))
 504                         die_errno ("Could not jump to working directory");
 505                 return rel && *rel ? strcat(rel, "/") : NULL;
 506         }
 507
 508         return retval;
 509 }