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 int check_filename(const char *prefix, const char *arg)
  65 {
  66         const char *name;
  67         struct stat st;
  68
  69         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  70         if (!lstat(name, &st))
  71                 return 1; /* file exists */
  72         if (errno == ENOENT || errno == ENOTDIR)
  73                 return 0; /* file does not exist */
  74         die_errno("failed to stat '%s'", arg);
  75 }
  76
  77 static void NORETURN die_verify_filename(const char *prefix, const char *arg)
  78 {
  79         unsigned char sha1[20];
  80         unsigned mode;
  81         /* try a detailed diagnostic ... */
  82         get_sha1_with_mode_1(arg, sha1, &mode, 0, prefix);
  83         /* ... or fall back the most general message. */
  84         die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  85             "Use '--' to separate paths from revisions", arg);
  86
  87 }
  88
  89 /*
  90  * Verify a filename that we got as an argument for a pathspec
  91  * entry. Note that a filename that begins with "-" never verifies
  92  * as true, because even if such a filename were to exist, we want
  93  * it to be preceded by the "--" marker (or we want the user to
  94  * use a format like "./-filename")
  95  */
  96 void verify_filename(const char *prefix, const char *arg)
  97 {
  98         if (*arg == '-')
  99                 die("bad flag '%s' used after filename", arg);
 100         if (check_filename(prefix, arg))
 101                 return;
 102         die_verify_filename(prefix, arg);
 103 }
 104
 105 /*
 106  * Opposite of the above: the command line did not have -- marker
 107  * and we parsed the arg as a refname.  It should not be interpretable
 108  * as a filename.
 109  */
 110 void verify_non_filename(const char *prefix, const char *arg)
 111 {
 112         if (!is_inside_work_tree() || is_inside_git_dir())
 113                 return;
 114         if (*arg == '-')
 115                 return; /* flag */
 116         if (!check_filename(prefix, arg))
 117                 return;
 118         die("ambiguous argument '%s': both revision and filename\n"
 119             "Use '--' to separate filenames from revisions", arg);
 120 }
 121
 122 const char **get_pathspec(const char *prefix, const char **pathspec)
 123 {
 124         const char *entry = *pathspec;
 125         const char **src, **dst;
 126         int prefixlen;
 127
 128         if (!prefix && !entry)
 129                 return NULL;
 130
 131         if (!entry) {
 132                 static const char *spec[2];
 133                 spec[0] = prefix;
 134                 spec[1] = NULL;
 135                 return spec;
 136         }
 137
 138         /* Otherwise we have to re-write the entries.. */
 139         src = pathspec;
 140         dst = pathspec;
 141         prefixlen = prefix ? strlen(prefix) : 0;
 142         while (*src) {
 143                 const char *p = prefix_path(prefix, prefixlen, *src);
 144                 *(dst++) = p;
 145                 src++;
 146         }
 147         *dst = NULL;
 148         if (!*pathspec)
 149                 return NULL;
 150         return pathspec;
 151 }
 152
 153 /*
 154  * Test if it looks like we're at a git directory.
 155  * We want to see:
 156  *
 157  *  - either an objects/ directory _or_ the proper
 158  *    GIT_OBJECT_DIRECTORY environment variable
 159  *  - a refs/ directory
 160  *  - either a HEAD symlink or a HEAD file that is formatted as
 161  *    a proper "ref:", or a regular file HEAD that has a properly
 162  *    formatted sha1 object name.
 163  */
 164 static int is_git_directory(const char *suspect)
 165 {
 166         char path[PATH_MAX];
 167         size_t len = strlen(suspect);
 168
 169         strcpy(path, suspect);
 170         if (getenv(DB_ENVIRONMENT)) {
 171                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 172                         return 0;
 173         }
 174         else {
 175                 strcpy(path + len, "/objects");
 176                 if (access(path, X_OK))
 177                         return 0;
 178         }
 179
 180         strcpy(path + len, "/refs");
 181         if (access(path, X_OK))
 182                 return 0;
 183
 184         strcpy(path + len, "/HEAD");
 185         if (validate_headref(path))
 186                 return 0;
 187
 188         return 1;
 189 }
 190
 191 int is_inside_git_dir(void)
 192 {
 193         if (inside_git_dir < 0)
 194                 inside_git_dir = is_inside_dir(get_git_dir());
 195         return inside_git_dir;
 196 }
 197
 198 int is_inside_work_tree(void)
 199 {
 200         if (inside_work_tree < 0)
 201                 inside_work_tree = is_inside_dir(get_git_work_tree());
 202         return inside_work_tree;
 203 }
 204
 205 /*
 206  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 207  * The old behaviour (which we retain here) is to set the work tree root
 208  * to the cwd, unless overridden by the config, the command line, or
 209  * GIT_WORK_TREE.
 210  */
 211 static const char *set_work_tree(const char *dir)
 212 {
 213         char buffer[PATH_MAX + 1];
 214
 215         if (!getcwd(buffer, sizeof(buffer)))
 216                 die ("Could not get the current working directory");
 217         git_work_tree_cfg = xstrdup(buffer);
 218         inside_work_tree = 1;
 219
 220         return NULL;
 221 }
 222
 223 void setup_work_tree(void)
 224 {
 225         const char *work_tree, *git_dir;
 226         static int initialized = 0;
 227
 228         if (initialized)
 229                 return;
 230         work_tree = get_git_work_tree();
 231         git_dir = get_git_dir();
 232         if (!is_absolute_path(git_dir))
 233                 git_dir = make_absolute_path(git_dir);
 234         if (!work_tree || chdir(work_tree))
 235                 die("This operation must be run in a work tree");
 236         set_git_dir(make_relative_path(git_dir, work_tree));
 237         initialized = 1;
 238 }
 239
 240 static int check_repository_format_gently(int *nongit_ok)
 241 {
 242         git_config(check_repository_format_version, NULL);
 243         if (GIT_REPO_VERSION < repository_format_version) {
 244                 if (!nongit_ok)
 245                         die ("Expected git repo version <= %d, found %d",
 246                              GIT_REPO_VERSION, repository_format_version);
 247                 warning("Expected git repo version <= %d, found %d",
 248                         GIT_REPO_VERSION, repository_format_version);
 249                 warning("Please upgrade Git");
 250                 *nongit_ok = -1;
 251                 return -1;
 252         }
 253         return 0;
 254 }
 255
 256 /*
 257  * Try to read the location of the git directory from the .git file,
 258  * return path to git directory if found.
 259  */
 260 const char *read_gitfile_gently(const char *path)
 261 {
 262         char *buf;
 263         struct stat st;
 264         int fd;
 265         size_t len;
 266
 267         if (stat(path, &st))
 268                 return NULL;
 269         if (!S_ISREG(st.st_mode))
 270                 return NULL;
 271         fd = open(path, O_RDONLY);
 272         if (fd < 0)
 273                 die_errno("Error opening '%s'", path);
 274         buf = xmalloc(st.st_size + 1);
 275         len = read_in_full(fd, buf, st.st_size);
 276         close(fd);
 277         if (len != st.st_size)
 278                 die("Error reading %s", path);
 279         buf[len] = '\0';
 280         if (prefixcmp(buf, "gitdir: "))
 281                 die("Invalid gitfile format: %s", path);
 282         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 283                 len--;
 284         if (len < 9)
 285                 die("No path in gitfile: %s", path);
 286         buf[len] = '\0';
 287         if (!is_git_directory(buf + 8))
 288                 die("Not a git repository: %s", buf + 8);
 289         path = make_absolute_path(buf + 8);
 290         free(buf);
 291         return path;
 292 }
 293
 294 /*
 295  * We cannot decide in this function whether we are in the work tree or
 296  * not, since the config can only be read _after_ this function was called.
 297  */
 298 const char *setup_git_directory_gently(int *nongit_ok)
 299 {
 300         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 301         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 302         static char cwd[PATH_MAX+1];
 303         const char *gitdirenv;
 304         const char *gitfile_dir;
 305         int len, offset, ceil_offset;
 306
 307         /*
 308          * Let's assume that we are in a git repository.
 309          * If it turns out later that we are somewhere else, the value will be
 310          * updated accordingly.
 311          */
 312         if (nongit_ok)
 313                 *nongit_ok = 0;
 314
 315         /*
 316          * If GIT_DIR is set explicitly, we're not going
 317          * to do any discovery, but we still do repository
 318          * validation.
 319          */
 320         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 321         if (gitdirenv) {
 322                 if (PATH_MAX - 40 < strlen(gitdirenv))
 323                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 324                 if (is_git_directory(gitdirenv)) {
 325                         static char buffer[1024 + 1];
 326                         const char *retval;
 327
 328                         if (!work_tree_env) {
 329                                 retval = set_work_tree(gitdirenv);
 330                                 /* config may override worktree */
 331                                 if (check_repository_format_gently(nongit_ok))
 332                                         return NULL;
 333                                 return retval;
 334                         }
 335                         if (check_repository_format_gently(nongit_ok))
 336                                 return NULL;
 337                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 338                                         get_git_work_tree());
 339                         if (!retval || !*retval)
 340                                 return NULL;
 341                         set_git_dir(make_absolute_path(gitdirenv));
 342                         if (chdir(work_tree_env) < 0)
 343                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 344                         strcat(buffer, "/");
 345                         return retval;
 346                 }
 347                 if (nongit_ok) {
 348                         *nongit_ok = 1;
 349                         return NULL;
 350                 }
 351                 die("Not a git repository: '%s'", gitdirenv);
 352         }
 353
 354         if (!getcwd(cwd, sizeof(cwd)-1))
 355                 die_errno("Unable to read current working directory");
 356
 357         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 358         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 359                 ceil_offset = 1;
 360
 361         /*
 362          * Test in the following order (relative to the cwd):
 363          * - .git (file containing "gitdir: <path>")
 364          * - .git/
 365          * - ./ (bare)
 366          * - ../.git
 367          * - ../.git/
 368          * - ../ (bare)
 369          * - ../../.git/
 370          *   etc.
 371          */
 372         offset = len = strlen(cwd);
 373         for (;;) {
 374                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 375                 if (gitfile_dir) {
 376                         if (set_git_dir(gitfile_dir))
 377                                 die("Repository setup failed");
 378                         break;
 379                 }
 380                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 381                         break;
 382                 if (is_git_directory(".")) {
 383                         inside_git_dir = 1;
 384                         if (!work_tree_env)
 385                                 inside_work_tree = 0;
 386                         if (offset != len) {
 387                                 cwd[offset] = '\0';
 388                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 389                         } else
 390                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 391                         check_repository_format_gently(nongit_ok);
 392                         return NULL;
 393                 }
 394                 while (--offset > ceil_offset && cwd[offset] != '/');
 395                 if (offset <= ceil_offset) {
 396                         if (nongit_ok) {
 397                                 if (chdir(cwd))
 398                                         die_errno("Cannot come back to cwd");
 399                                 *nongit_ok = 1;
 400                                 return NULL;
 401                         }
 402                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 403                 }
 404                 if (chdir(".."))
 405                         die_errno("Cannot change to '%s/..'", cwd);
 406         }
 407
 408         inside_git_dir = 0;
 409         if (!work_tree_env)
 410                 inside_work_tree = 1;
 411         git_work_tree_cfg = xstrndup(cwd, offset);
 412         if (check_repository_format_gently(nongit_ok))
 413                 return NULL;
 414         if (offset == len)
 415                 return NULL;
 416
 417         /* Make "offset" point to past the '/', and add a '/' at the end */
 418         offset++;
 419         cwd[len++] = '/';
 420         cwd[len] = 0;
 421         return cwd + offset;
 422 }
 423
 424 int git_config_perm(const char *var, const char *value)
 425 {
 426         int i;
 427         char *endptr;
 428
 429         if (value == NULL)
 430                 return PERM_GROUP;
 431
 432         if (!strcmp(value, "umask"))
 433                 return PERM_UMASK;
 434         if (!strcmp(value, "group"))
 435                 return PERM_GROUP;
 436         if (!strcmp(value, "all") ||
 437             !strcmp(value, "world") ||
 438             !strcmp(value, "everybody"))
 439                 return PERM_EVERYBODY;
 440
 441         /* Parse octal numbers */
 442         i = strtol(value, &endptr, 8);
 443
 444         /* If not an octal number, maybe true/false? */
 445         if (*endptr != 0)
 446                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 447
 448         /*
 449          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 450          * a chmod value to restrict to.
 451          */
 452         switch (i) {
 453         case PERM_UMASK:               /* 0 */
 454                 return PERM_UMASK;
 455         case OLD_PERM_GROUP:           /* 1 */
 456                 return PERM_GROUP;
 457         case OLD_PERM_EVERYBODY:       /* 2 */
 458                 return PERM_EVERYBODY;
 459         }
 460
 461         /* A filemode value was given: 0xxx */
 462
 463         if ((i & 0600) != 0600)
 464                 die("Problem with core.sharedRepository filemode value "
 465                     "(0%.3o).\nThe owner of files must always have "
 466                     "read and write permissions.", i);
 467
 468         /*
 469          * Mask filemode value. Others can not get write permission.
 470          * x flags for directories are handled separately.
 471          */
 472         return -(i & 0666);
 473 }
 474
 475 int check_repository_format_version(const char *var, const char *value, void *cb)
 476 {
 477         if (strcmp(var, "core.repositoryformatversion") == 0)
 478                 repository_format_version = git_config_int(var, value);
 479         else if (strcmp(var, "core.sharedrepository") == 0)
 480                 shared_repository = git_config_perm(var, value);
 481         else if (strcmp(var, "core.bare") == 0) {
 482                 is_bare_repository_cfg = git_config_bool(var, value);
 483                 if (is_bare_repository_cfg == 1)
 484                         inside_work_tree = -1;
 485         } else if (strcmp(var, "core.worktree") == 0) {
 486                 if (!value)
 487                         return config_error_nonbool(var);
 488                 free(git_work_tree_cfg);
 489                 git_work_tree_cfg = xstrdup(value);
 490                 inside_work_tree = -1;
 491         }
 492         return 0;
 493 }
 494
 495 int check_repository_format(void)
 496 {
 497         return check_repository_format_gently(NULL);
 498 }
 499
 500 const char *setup_git_directory(void)
 501 {
 502         const char *retval = setup_git_directory_gently(NULL);
 503
 504         /* If the work tree is not the default one, recompute prefix */
 505         if (inside_work_tree < 0) {
 506                 static char buffer[PATH_MAX + 1];
 507                 char *rel;
 508                 if (retval && chdir(retval))
 509                         die_errno ("Could not jump back into original cwd");
 510                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 511                 if (rel && *rel && chdir(get_git_work_tree()))
 512                         die_errno ("Could not jump to working directory");
 513                 return rel && *rel ? strcat(rel, "/") : NULL;
 514         }
 515
 516         return retval;
 517 }