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 int check_filename(const char *prefix, const char *arg)
  68 {
  69         const char *name;
  70         struct stat st;
  71
  72         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
  73         if (!lstat(name, &st))
  74                 return 1; /* file exists */
  75         if (errno == ENOENT || errno == ENOTDIR)
  76                 return 0; /* file does not exist */
  77         die_errno("failed to stat '%s'", arg);
  78 }
  79
  80 /*
  81  * Verify a filename that we got as an argument for a pathspec
  82  * entry. Note that a filename that begins with "-" never verifies
  83  * as true, because even if such a filename were to exist, we want
  84  * it to be preceded by the "--" marker (or we want the user to
  85  * use a format like "./-filename")
  86  */
  87 void verify_filename(const char *prefix, const char *arg)
  88 {
  89         if (*arg == '-')
  90                 die("bad flag '%s' used after filename", arg);
  91         if (check_filename(prefix, arg))
  92                 return;
  93         die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  94             "Use '--' to separate paths from revisions", arg);
  95 }
  96
  97 /*
  98  * Opposite of the above: the command line did not have -- marker
  99  * and we parsed the arg as a refname.  It should not be interpretable
 100  * as a filename.
 101  */
 102 void verify_non_filename(const char *prefix, const char *arg)
 103 {
 104         if (!is_inside_work_tree() || is_inside_git_dir())
 105                 return;
 106         if (*arg == '-')
 107                 return; /* flag */
 108         if (!check_filename(prefix, arg))
 109                 return;
 110         die("ambiguous argument '%s': both revision and filename\n"
 111             "Use '--' to separate filenames from revisions", arg);
 112 }
 113
 114 const char **get_pathspec(const char *prefix, const char **pathspec)
 115 {
 116         const char *entry = *pathspec;
 117         const char **src, **dst;
 118         int prefixlen;
 119
 120         if (!prefix && !entry)
 121                 return NULL;
 122
 123         if (!entry) {
 124                 static const char *spec[2];
 125                 spec[0] = prefix;
 126                 spec[1] = NULL;
 127                 return spec;
 128         }
 129
 130         /* Otherwise we have to re-write the entries.. */
 131         src = pathspec;
 132         dst = pathspec;
 133         prefixlen = prefix ? strlen(prefix) : 0;
 134         while (*src) {
 135                 const char *p = prefix_path(prefix, prefixlen, *src);
 136                 *(dst++) = p;
 137                 src++;
 138         }
 139         *dst = NULL;
 140         if (!*pathspec)
 141                 return NULL;
 142         return pathspec;
 143 }
 144
 145 /*
 146  * Test if it looks like we're at a git directory.
 147  * We want to see:
 148  *
 149  *  - either an objects/ directory _or_ the proper
 150  *    GIT_OBJECT_DIRECTORY environment variable
 151  *  - a refs/ directory
 152  *  - either a HEAD symlink or a HEAD file that is formatted as
 153  *    a proper "ref:", or a regular file HEAD that has a properly
 154  *    formatted sha1 object name.
 155  */
 156 static int is_git_directory(const char *suspect)
 157 {
 158         char path[PATH_MAX];
 159         size_t len = strlen(suspect);
 160
 161         if (PATH_MAX <= len + strlen("/objects"))
 162                 die("Too long path: %.*s", 60, suspect);
 163         strcpy(path, suspect);
 164         if (getenv(DB_ENVIRONMENT)) {
 165                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 166                         return 0;
 167         }
 168         else {
 169                 strcpy(path + len, "/objects");
 170                 if (access(path, X_OK))
 171                         return 0;
 172         }
 173
 174         strcpy(path + len, "/refs");
 175         if (access(path, X_OK))
 176                 return 0;
 177
 178         strcpy(path + len, "/HEAD");
 179         if (validate_headref(path))
 180                 return 0;
 181
 182         return 1;
 183 }
 184
 185 int is_inside_git_dir(void)
 186 {
 187         if (inside_git_dir < 0)
 188                 inside_git_dir = is_inside_dir(get_git_dir());
 189         return inside_git_dir;
 190 }
 191
 192 int is_inside_work_tree(void)
 193 {
 194         if (inside_work_tree < 0)
 195                 inside_work_tree = is_inside_dir(get_git_work_tree());
 196         return inside_work_tree;
 197 }
 198
 199 /*
 200  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 201  * The old behaviour (which we retain here) is to set the work tree root
 202  * to the cwd, unless overridden by the config, the command line, or
 203  * GIT_WORK_TREE.
 204  */
 205 static const char *set_work_tree(const char *dir)
 206 {
 207         char buffer[PATH_MAX + 1];
 208
 209         if (!getcwd(buffer, sizeof(buffer)))
 210                 die ("Could not get the current working directory");
 211         git_work_tree_cfg = xstrdup(buffer);
 212         inside_work_tree = 1;
 213
 214         return NULL;
 215 }
 216
 217 void setup_work_tree(void)
 218 {
 219         const char *work_tree, *git_dir;
 220         static int initialized = 0;
 221
 222         if (initialized)
 223                 return;
 224         work_tree = get_git_work_tree();
 225         git_dir = get_git_dir();
 226         if (!is_absolute_path(git_dir))
 227                 git_dir = make_absolute_path(git_dir);
 228         if (!work_tree || chdir(work_tree))
 229                 die("This operation must be run in a work tree");
 230         set_git_dir(make_relative_path(git_dir, work_tree));
 231         initialized = 1;
 232 }
 233
 234 static int check_repository_format_gently(int *nongit_ok)
 235 {
 236         git_config(check_repository_format_version, NULL);
 237         if (GIT_REPO_VERSION < repository_format_version) {
 238                 if (!nongit_ok)
 239                         die ("Expected git repo version <= %d, found %d",
 240                              GIT_REPO_VERSION, repository_format_version);
 241                 warning("Expected git repo version <= %d, found %d",
 242                         GIT_REPO_VERSION, repository_format_version);
 243                 warning("Please upgrade Git");
 244                 *nongit_ok = -1;
 245                 return -1;
 246         }
 247         return 0;
 248 }
 249
 250 /*
 251  * Try to read the location of the git directory from the .git file,
 252  * return path to git directory if found.
 253  */
 254 const char *read_gitfile_gently(const char *path)
 255 {
 256         char *buf;
 257         struct stat st;
 258         int fd;
 259         size_t len;
 260
 261         if (stat(path, &st))
 262                 return NULL;
 263         if (!S_ISREG(st.st_mode))
 264                 return NULL;
 265         fd = open(path, O_RDONLY);
 266         if (fd < 0)
 267                 die_errno("Error opening '%s'", path);
 268         buf = xmalloc(st.st_size + 1);
 269         len = read_in_full(fd, buf, st.st_size);
 270         close(fd);
 271         if (len != st.st_size)
 272                 die("Error reading %s", path);
 273         buf[len] = '\0';
 274         if (prefixcmp(buf, "gitdir: "))
 275                 die("Invalid gitfile format: %s", path);
 276         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 277                 len--;
 278         if (len < 9)
 279                 die("No path in gitfile: %s", path);
 280         buf[len] = '\0';
 281         if (!is_git_directory(buf + 8))
 282                 die("Not a git repository: %s", buf + 8);
 283         path = make_absolute_path(buf + 8);
 284         free(buf);
 285         return path;
 286 }
 287
 288 /*
 289  * We cannot decide in this function whether we are in the work tree or
 290  * not, since the config can only be read _after_ this function was called.
 291  */
 292 const char *setup_git_directory_gently(int *nongit_ok)
 293 {
 294         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 295         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 296         static char cwd[PATH_MAX+1];
 297         const char *gitdirenv;
 298         const char *gitfile_dir;
 299         int len, offset, ceil_offset;
 300
 301         /*
 302          * Let's assume that we are in a git repository.
 303          * If it turns out later that we are somewhere else, the value will be
 304          * updated accordingly.
 305          */
 306         if (nongit_ok)
 307                 *nongit_ok = 0;
 308
 309         /*
 310          * If GIT_DIR is set explicitly, we're not going
 311          * to do any discovery, but we still do repository
 312          * validation.
 313          */
 314         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 315         if (gitdirenv) {
 316                 if (PATH_MAX - 40 < strlen(gitdirenv))
 317                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 318                 if (is_git_directory(gitdirenv)) {
 319                         static char buffer[1024 + 1];
 320                         const char *retval;
 321
 322                         if (!work_tree_env) {
 323                                 retval = set_work_tree(gitdirenv);
 324                                 /* config may override worktree */
 325                                 if (check_repository_format_gently(nongit_ok))
 326                                         return NULL;
 327                                 return retval;
 328                         }
 329                         if (check_repository_format_gently(nongit_ok))
 330                                 return NULL;
 331                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 332                                         get_git_work_tree());
 333                         if (!retval || !*retval)
 334                                 return NULL;
 335                         set_git_dir(make_absolute_path(gitdirenv));
 336                         if (chdir(work_tree_env) < 0)
 337                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 338                         strcat(buffer, "/");
 339                         return retval;
 340                 }
 341                 if (nongit_ok) {
 342                         *nongit_ok = 1;
 343                         return NULL;
 344                 }
 345                 die("Not a git repository: '%s'", gitdirenv);
 346         }
 347
 348         if (!getcwd(cwd, sizeof(cwd)-1))
 349                 die_errno("Unable to read current working directory");
 350
 351         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 352         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 353                 ceil_offset = 1;
 354
 355         /*
 356          * Test in the following order (relative to the cwd):
 357          * - .git (file containing "gitdir: <path>")
 358          * - .git/
 359          * - ./ (bare)
 360          * - ../.git
 361          * - ../.git/
 362          * - ../ (bare)
 363          * - ../../.git/
 364          *   etc.
 365          */
 366         offset = len = strlen(cwd);
 367         for (;;) {
 368                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 369                 if (gitfile_dir) {
 370                         if (set_git_dir(gitfile_dir))
 371                                 die("Repository setup failed");
 372                         break;
 373                 }
 374                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 375                         break;
 376                 if (is_git_directory(".")) {
 377                         inside_git_dir = 1;
 378                         if (!work_tree_env)
 379                                 inside_work_tree = 0;
 380                         if (offset != len) {
 381                                 cwd[offset] = '\0';
 382                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 383                         } else
 384                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 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         git_work_tree_cfg = xstrndup(cwd, offset);
 406         if (check_repository_format_gently(nongit_ok))
 407                 return NULL;
 408         if (offset == len)
 409                 return NULL;
 410
 411         /* Make "offset" point to past the '/', and add a '/' at the end */
 412         offset++;
 413         cwd[len++] = '/';
 414         cwd[len] = 0;
 415         return cwd + offset;
 416 }
 417
 418 int git_config_perm(const char *var, const char *value)
 419 {
 420         int i;
 421         char *endptr;
 422
 423         if (value == NULL)
 424                 return PERM_GROUP;
 425
 426         if (!strcmp(value, "umask"))
 427                 return PERM_UMASK;
 428         if (!strcmp(value, "group"))
 429                 return PERM_GROUP;
 430         if (!strcmp(value, "all") ||
 431             !strcmp(value, "world") ||
 432             !strcmp(value, "everybody"))
 433                 return PERM_EVERYBODY;
 434
 435         /* Parse octal numbers */
 436         i = strtol(value, &endptr, 8);
 437
 438         /* If not an octal number, maybe true/false? */
 439         if (*endptr != 0)
 440                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 441
 442         /*
 443          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 444          * a chmod value to restrict to.
 445          */
 446         switch (i) {
 447         case PERM_UMASK:               /* 0 */
 448                 return PERM_UMASK;
 449         case OLD_PERM_GROUP:           /* 1 */
 450                 return PERM_GROUP;
 451         case OLD_PERM_EVERYBODY:       /* 2 */
 452                 return PERM_EVERYBODY;
 453         }
 454
 455         /* A filemode value was given: 0xxx */
 456
 457         if ((i & 0600) != 0600)
 458                 die("Problem with core.sharedRepository filemode value "
 459                     "(0%.3o).\nThe owner of files must always have "
 460                     "read and write permissions.", i);
 461
 462         /*
 463          * Mask filemode value. Others can not get write permission.
 464          * x flags for directories are handled separately.
 465          */
 466         return -(i & 0666);
 467 }
 468
 469 int check_repository_format_version(const char *var, const char *value, void *cb)
 470 {
 471         if (strcmp(var, "core.repositoryformatversion") == 0)
 472                 repository_format_version = git_config_int(var, value);
 473         else if (strcmp(var, "core.sharedrepository") == 0)
 474                 shared_repository = git_config_perm(var, value);
 475         else if (strcmp(var, "core.bare") == 0) {
 476                 is_bare_repository_cfg = git_config_bool(var, value);
 477                 if (is_bare_repository_cfg == 1)
 478                         inside_work_tree = -1;
 479         } else if (strcmp(var, "core.worktree") == 0) {
 480                 if (!value)
 481                         return config_error_nonbool(var);
 482                 free(git_work_tree_cfg);
 483                 git_work_tree_cfg = xstrdup(value);
 484                 inside_work_tree = -1;
 485         }
 486         return 0;
 487 }
 488
 489 int check_repository_format(void)
 490 {
 491         return check_repository_format_gently(NULL);
 492 }
 493
 494 const char *setup_git_directory(void)
 495 {
 496         const char *retval = setup_git_directory_gently(NULL);
 497
 498         /* If the work tree is not the default one, recompute prefix */
 499         if (inside_work_tree < 0) {
 500                 static char buffer[PATH_MAX + 1];
 501                 char *rel;
 502                 if (retval && chdir(retval))
 503                         die_errno ("Could not jump back into original cwd");
 504                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 505                 if (rel && *rel && chdir(get_git_work_tree()))
 506                         die_errno ("Could not jump to working directory");
 507                 return rel && *rel ? strcat(rel, "/") : NULL;
 508         }
 509
 510         return retval;
 511 }