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