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 /*
  82  * Verify a filename that we got as an argument for a pathspec
  83  * entry. Note that a filename that begins with "-" never verifies
  84  * as true, because even if such a filename were to exist, we want
  85  * it to be preceded by the "--" marker (or we want the user to
  86  * use a format like "./-filename")
  87  */
  88 void verify_filename(const char *prefix, const char *arg)
  89 {
  90         if (*arg == '-')
  91                 die("bad flag '%s' used after filename", arg);
  92         if (check_filename(prefix, arg))
  93                 return;
  94         die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  95             "Use '--' to separate paths from revisions", arg);
  96 }
  97
  98 /*
  99  * Opposite of the above: the command line did not have -- marker
 100  * and we parsed the arg as a refname.  It should not be interpretable
 101  * as a filename.
 102  */
 103 void verify_non_filename(const char *prefix, const char *arg)
 104 {
 105         if (!is_inside_work_tree() || is_inside_git_dir())
 106                 return;
 107         if (*arg == '-')
 108                 return; /* flag */
 109         if (!check_filename(prefix, arg))
 110                 return;
 111         die("ambiguous argument '%s': both revision and filename\n"
 112             "Use '--' to separate filenames from revisions", arg);
 113 }
 114
 115 const char **get_pathspec(const char *prefix, const char **pathspec)
 116 {
 117         const char *entry = *pathspec;
 118         const char **src, **dst;
 119         int prefixlen;
 120
 121         if (!prefix && !entry)
 122                 return NULL;
 123
 124         if (!entry) {
 125                 static const char *spec[2];
 126                 spec[0] = prefix;
 127                 spec[1] = NULL;
 128                 return spec;
 129         }
 130
 131         /* Otherwise we have to re-write the entries.. */
 132         src = pathspec;
 133         dst = pathspec;
 134         prefixlen = prefix ? strlen(prefix) : 0;
 135         while (*src) {
 136                 const char *p = prefix_path(prefix, prefixlen, *src);
 137                 *(dst++) = p;
 138                 src++;
 139         }
 140         *dst = NULL;
 141         if (!*pathspec)
 142                 return NULL;
 143         return pathspec;
 144 }
 145
 146 /*
 147  * Test if it looks like we're at a git directory.
 148  * We want to see:
 149  *
 150  *  - either an objects/ directory _or_ the proper
 151  *    GIT_OBJECT_DIRECTORY environment variable
 152  *  - a refs/ directory
 153  *  - either a HEAD symlink or a HEAD file that is formatted as
 154  *    a proper "ref:", or a regular file HEAD that has a properly
 155  *    formatted sha1 object name.
 156  */
 157 static int is_git_directory(const char *suspect)
 158 {
 159         char path[PATH_MAX];
 160         size_t len = strlen(suspect);
 161
 162         strcpy(path, suspect);
 163         if (getenv(DB_ENVIRONMENT)) {
 164                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 165                         return 0;
 166         }
 167         else {
 168                 strcpy(path + len, "/objects");
 169                 if (access(path, X_OK))
 170                         return 0;
 171         }
 172
 173         strcpy(path + len, "/refs");
 174         if (access(path, X_OK))
 175                 return 0;
 176
 177         strcpy(path + len, "/HEAD");
 178         if (validate_headref(path))
 179                 return 0;
 180
 181         return 1;
 182 }
 183
 184 int is_inside_git_dir(void)
 185 {
 186         if (inside_git_dir < 0)
 187                 inside_git_dir = is_inside_dir(get_git_dir());
 188         return inside_git_dir;
 189 }
 190
 191 int is_inside_work_tree(void)
 192 {
 193         if (inside_work_tree < 0)
 194                 inside_work_tree = is_inside_dir(get_git_work_tree());
 195         return inside_work_tree;
 196 }
 197
 198 /*
 199  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 200  * The old behaviour (which we retain here) is to set the work tree root
 201  * to the cwd, unless overridden by the config, the command line, or
 202  * GIT_WORK_TREE.
 203  */
 204 static const char *set_work_tree(const char *dir)
 205 {
 206         char buffer[PATH_MAX + 1];
 207
 208         if (!getcwd(buffer, sizeof(buffer)))
 209                 die ("Could not get the current working directory");
 210         git_work_tree_cfg = xstrdup(buffer);
 211         inside_work_tree = 1;
 212
 213         return NULL;
 214 }
 215
 216 void setup_work_tree(void)
 217 {
 218         const char *work_tree, *git_dir;
 219         static int initialized = 0;
 220
 221         if (initialized)
 222                 return;
 223         work_tree = get_git_work_tree();
 224         git_dir = get_git_dir();
 225         if (!is_absolute_path(git_dir))
 226                 git_dir = make_absolute_path(git_dir);
 227         if (!work_tree || chdir(work_tree))
 228                 die("This operation must be run in a work tree");
 229         set_git_dir(make_relative_path(git_dir, work_tree));
 230         initialized = 1;
 231 }
 232
 233 static int check_repository_format_gently(int *nongit_ok)
 234 {
 235         git_config(check_repository_format_version, NULL);
 236         if (GIT_REPO_VERSION < repository_format_version) {
 237                 if (!nongit_ok)
 238                         die ("Expected git repo version <= %d, found %d",
 239                              GIT_REPO_VERSION, repository_format_version);
 240                 warning("Expected git repo version <= %d, found %d",
 241                         GIT_REPO_VERSION, repository_format_version);
 242                 warning("Please upgrade Git");
 243                 *nongit_ok = -1;
 244                 return -1;
 245         }
 246         return 0;
 247 }
 248
 249 /*
 250  * Try to read the location of the git directory from the .git file,
 251  * return path to git directory if found.
 252  */
 253 const char *read_gitfile_gently(const char *path)
 254 {
 255         char *buf;
 256         struct stat st;
 257         int fd;
 258         size_t len;
 259
 260         if (stat(path, &st))
 261                 return NULL;
 262         if (!S_ISREG(st.st_mode))
 263                 return NULL;
 264         fd = open(path, O_RDONLY);
 265         if (fd < 0)
 266                 die_errno("Error opening '%s'", path);
 267         buf = xmalloc(st.st_size + 1);
 268         len = read_in_full(fd, buf, st.st_size);
 269         close(fd);
 270         if (len != st.st_size)
 271                 die("Error reading %s", path);
 272         buf[len] = '\0';
 273         if (prefixcmp(buf, "gitdir: "))
 274                 die("Invalid gitfile format: %s", path);
 275         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 276                 len--;
 277         if (len < 9)
 278                 die("No path in gitfile: %s", path);
 279         buf[len] = '\0';
 280         if (!is_git_directory(buf + 8))
 281                 die("Not a git repository: %s", buf + 8);
 282         path = make_absolute_path(buf + 8);
 283         free(buf);
 284         return path;
 285 }
 286
 287 /*
 288  * We cannot decide in this function whether we are in the work tree or
 289  * not, since the config can only be read _after_ this function was called.
 290  */
 291 const char *setup_git_directory_gently(int *nongit_ok)
 292 {
 293         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 294         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 295         static char cwd[PATH_MAX+1];
 296         const char *gitdirenv;
 297         const char *gitfile_dir;
 298         int len, offset, ceil_offset, root_len;
 299
 300         /*
 301          * Let's assume that we are in a git repository.
 302          * If it turns out later that we are somewhere else, the value will be
 303          * updated accordingly.
 304          */
 305         if (nongit_ok)
 306                 *nongit_ok = 0;
 307
 308         /*
 309          * If GIT_DIR is set explicitly, we're not going
 310          * to do any discovery, but we still do repository
 311          * validation.
 312          */
 313         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 314         if (gitdirenv) {
 315                 if (PATH_MAX - 40 < strlen(gitdirenv))
 316                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 317                 if (is_git_directory(gitdirenv)) {
 318                         static char buffer[1024 + 1];
 319                         const char *retval;
 320
 321                         if (!work_tree_env) {
 322                                 retval = set_work_tree(gitdirenv);
 323                                 /* config may override worktree */
 324                                 if (check_repository_format_gently(nongit_ok))
 325                                         return NULL;
 326                                 return retval;
 327                         }
 328                         if (check_repository_format_gently(nongit_ok))
 329                                 return NULL;
 330                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 331                                         get_git_work_tree());
 332                         if (!retval || !*retval)
 333                                 return NULL;
 334                         set_git_dir(make_absolute_path(gitdirenv));
 335                         if (chdir(work_tree_env) < 0)
 336                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 337                         strcat(buffer, "/");
 338                         return retval;
 339                 }
 340                 if (nongit_ok) {
 341                         *nongit_ok = 1;
 342                         return NULL;
 343                 }
 344                 die("Not a git repository: '%s'", gitdirenv);
 345         }
 346
 347         if (!getcwd(cwd, sizeof(cwd)-1))
 348                 die_errno("Unable to read current working directory");
 349
 350         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 351         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 352                 ceil_offset = 1;
 353
 354         /*
 355          * Test in the following order (relative to the cwd):
 356          * - .git (file containing "gitdir: <path>")
 357          * - .git/
 358          * - ./ (bare)
 359          * - ../.git
 360          * - ../.git/
 361          * - ../ (bare)
 362          * - ../../.git/
 363          *   etc.
 364          */
 365         offset = len = strlen(cwd);
 366         for (;;) {
 367                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 368                 if (gitfile_dir) {
 369                         if (set_git_dir(gitfile_dir))
 370                                 die("Repository setup failed");
 371                         break;
 372                 }
 373                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 374                         break;
 375                 if (is_git_directory(".")) {
 376                         inside_git_dir = 1;
 377                         if (!work_tree_env)
 378                                 inside_work_tree = 0;
 379                         if (offset != len) {
 380                                 root_len = offset_1st_component(cwd);
 381                                 cwd[offset > root_len ? offset : root_len] = '\0';
 382                                 set_git_dir(cwd);
 383                         } else
 384                                 set_git_dir(".");
 385                         check_repository_format_gently(nongit_ok);
 386                         return NULL;
 387                 }
 388                 while (--offset > ceil_offset && cwd[offset] != '/');
 389                 if (offset <= ceil_offset) {
 390                         if (nongit_ok) {
 391                                 if (chdir(cwd))
 392                                         die_errno("Cannot come back to cwd");
 393                                 *nongit_ok = 1;
 394                                 return NULL;
 395                         }
 396                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 397                 }
 398                 if (chdir(".."))
 399                         die_errno("Cannot change to '%s/..'", cwd);
 400         }
 401
 402         inside_git_dir = 0;
 403         if (!work_tree_env)
 404                 inside_work_tree = 1;
 405         root_len = offset_1st_component(cwd);
 406         git_work_tree_cfg = xstrndup(cwd, offset > root_len ? offset : root_len);
 407         if (check_repository_format_gently(nongit_ok))
 408                 return NULL;
 409         if (offset == len)
 410                 return NULL;
 411
 412         /* Make "offset" point to past the '/', and add a '/' at the end */
 413         offset++;
 414         cwd[len++] = '/';
 415         cwd[len] = 0;
 416         return cwd + offset;
 417 }
 418
 419 int git_config_perm(const char *var, const char *value)
 420 {
 421         int i;
 422         char *endptr;
 423
 424         if (value == NULL)
 425                 return PERM_GROUP;
 426
 427         if (!strcmp(value, "umask"))
 428                 return PERM_UMASK;
 429         if (!strcmp(value, "group"))
 430                 return PERM_GROUP;
 431         if (!strcmp(value, "all") ||
 432             !strcmp(value, "world") ||
 433             !strcmp(value, "everybody"))
 434                 return PERM_EVERYBODY;
 435
 436         /* Parse octal numbers */
 437         i = strtol(value, &endptr, 8);
 438
 439         /* If not an octal number, maybe true/false? */
 440         if (*endptr != 0)
 441                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 442
 443         /*
 444          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 445          * a chmod value to restrict to.
 446          */
 447         switch (i) {
 448         case PERM_UMASK:               /* 0 */
 449                 return PERM_UMASK;
 450         case OLD_PERM_GROUP:           /* 1 */
 451                 return PERM_GROUP;
 452         case OLD_PERM_EVERYBODY:       /* 2 */
 453                 return PERM_EVERYBODY;
 454         }
 455
 456         /* A filemode value was given: 0xxx */
 457
 458         if ((i & 0600) != 0600)
 459                 die("Problem with core.sharedRepository filemode value "
 460                     "(0%.3o).\nThe owner of files must always have "
 461                     "read and write permissions.", i);
 462
 463         /*
 464          * Mask filemode value. Others can not get write permission.
 465          * x flags for directories are handled separately.
 466          */
 467         return -(i & 0666);
 468 }
 469
 470 int check_repository_format_version(const char *var, const char *value, void *cb)
 471 {
 472         if (strcmp(var, "core.repositoryformatversion") == 0)
 473                 repository_format_version = git_config_int(var, value);
 474         else if (strcmp(var, "core.sharedrepository") == 0)
 475                 shared_repository = git_config_perm(var, value);
 476         else if (strcmp(var, "core.bare") == 0) {
 477                 is_bare_repository_cfg = git_config_bool(var, value);
 478                 if (is_bare_repository_cfg == 1)
 479                         inside_work_tree = -1;
 480         } else if (strcmp(var, "core.worktree") == 0) {
 481                 if (!value)
 482                         return config_error_nonbool(var);
 483                 free(git_work_tree_cfg);
 484                 git_work_tree_cfg = xstrdup(value);
 485                 inside_work_tree = -1;
 486         }
 487         return 0;
 488 }
 489
 490 int check_repository_format(void)
 491 {
 492         return check_repository_format_gently(NULL);
 493 }
 494
 495 const char *setup_git_directory(void)
 496 {
 497         const char *retval = setup_git_directory_gently(NULL);
 498
 499         /* If the work tree is not the default one, recompute prefix */
 500         if (inside_work_tree < 0) {
 501                 static char buffer[PATH_MAX + 1];
 502                 char *rel;
 503                 if (retval && chdir(retval))
 504                         die_errno ("Could not jump back into original cwd");
 505                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 506                 if (rel && *rel && chdir(get_git_work_tree()))
 507                         die_errno ("Could not jump to working directory");
 508                 return rel && *rel ? strcat(rel, "/") : NULL;
 509         }
 510
 511         return retval;
 512 }