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         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         char *dir;
 256         const char *slash;
 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         dir = buf + 8;
 282
 283         if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
 284                 size_t pathlen = slash+1 - path;
 285                 size_t dirlen = pathlen + len - 8;
 286                 dir = xmalloc(dirlen + 1);
 287                 strncpy(dir, path, pathlen);
 288                 strncpy(dir + pathlen, buf + 8, len - 8);
 289                 dir[dirlen] = '\0';
 290                 free(buf);
 291                 buf = dir;
 292         }
 293
 294         if (!is_git_directory(dir))
 295                 die("Not a git repository: %s", dir);
 296         path = make_absolute_path(dir);
 297
 298         free(buf);
 299         return path;
 300 }
 301
 302 /*
 303  * We cannot decide in this function whether we are in the work tree or
 304  * not, since the config can only be read _after_ this function was called.
 305  */
 306 const char *setup_git_directory_gently(int *nongit_ok)
 307 {
 308         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 309         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 310         static char cwd[PATH_MAX+1];
 311         const char *gitdirenv;
 312         const char *gitfile_dir;
 313         int len, offset, ceil_offset;
 314
 315         /*
 316          * Let's assume that we are in a git repository.
 317          * If it turns out later that we are somewhere else, the value will be
 318          * updated accordingly.
 319          */
 320         if (nongit_ok)
 321                 *nongit_ok = 0;
 322
 323         /*
 324          * If GIT_DIR is set explicitly, we're not going
 325          * to do any discovery, but we still do repository
 326          * validation.
 327          */
 328         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 329         if (gitdirenv) {
 330                 if (PATH_MAX - 40 < strlen(gitdirenv))
 331                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 332                 if (is_git_directory(gitdirenv)) {
 333                         static char buffer[1024 + 1];
 334                         const char *retval;
 335
 336                         if (!work_tree_env) {
 337                                 retval = set_work_tree(gitdirenv);
 338                                 /* config may override worktree */
 339                                 if (check_repository_format_gently(nongit_ok))
 340                                         return NULL;
 341                                 return retval;
 342                         }
 343                         if (check_repository_format_gently(nongit_ok))
 344                                 return NULL;
 345                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 346                                         get_git_work_tree());
 347                         if (!retval || !*retval)
 348                                 return NULL;
 349                         set_git_dir(make_absolute_path(gitdirenv));
 350                         if (chdir(work_tree_env) < 0)
 351                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 352                         strcat(buffer, "/");
 353                         return retval;
 354                 }
 355                 if (nongit_ok) {
 356                         *nongit_ok = 1;
 357                         return NULL;
 358                 }
 359                 die("Not a git repository: '%s'", gitdirenv);
 360         }
 361
 362         if (!getcwd(cwd, sizeof(cwd)-1))
 363                 die_errno("Unable to read current working directory");
 364
 365         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 366         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 367                 ceil_offset = 1;
 368
 369         /*
 370          * Test in the following order (relative to the cwd):
 371          * - .git (file containing "gitdir: <path>")
 372          * - .git/
 373          * - ./ (bare)
 374          * - ../.git
 375          * - ../.git/
 376          * - ../ (bare)
 377          * - ../../.git/
 378          *   etc.
 379          */
 380         offset = len = strlen(cwd);
 381         for (;;) {
 382                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 383                 if (gitfile_dir) {
 384                         if (set_git_dir(gitfile_dir))
 385                                 die("Repository setup failed");
 386                         break;
 387                 }
 388                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 389                         break;
 390                 if (is_git_directory(".")) {
 391                         inside_git_dir = 1;
 392                         if (!work_tree_env)
 393                                 inside_work_tree = 0;
 394                         if (offset != len) {
 395                                 cwd[offset] = '\0';
 396                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 397                         } else
 398                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 399                         check_repository_format_gently(nongit_ok);
 400                         return NULL;
 401                 }
 402                 while (--offset > ceil_offset && cwd[offset] != '/');
 403                 if (offset <= ceil_offset) {
 404                         if (nongit_ok) {
 405                                 if (chdir(cwd))
 406                                         die_errno("Cannot come back to cwd");
 407                                 *nongit_ok = 1;
 408                                 return NULL;
 409                         }
 410                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 411                 }
 412                 if (chdir(".."))
 413                         die_errno("Cannot change to '%s/..'", cwd);
 414         }
 415
 416         inside_git_dir = 0;
 417         if (!work_tree_env)
 418                 inside_work_tree = 1;
 419         git_work_tree_cfg = xstrndup(cwd, offset);
 420         if (check_repository_format_gently(nongit_ok))
 421                 return NULL;
 422         if (offset == len)
 423                 return NULL;
 424
 425         /* Make "offset" point to past the '/', and add a '/' at the end */
 426         offset++;
 427         cwd[len++] = '/';
 428         cwd[len] = 0;
 429         return cwd + offset;
 430 }
 431
 432 int git_config_perm(const char *var, const char *value)
 433 {
 434         int i;
 435         char *endptr;
 436
 437         if (value == NULL)
 438                 return PERM_GROUP;
 439
 440         if (!strcmp(value, "umask"))
 441                 return PERM_UMASK;
 442         if (!strcmp(value, "group"))
 443                 return PERM_GROUP;
 444         if (!strcmp(value, "all") ||
 445             !strcmp(value, "world") ||
 446             !strcmp(value, "everybody"))
 447                 return PERM_EVERYBODY;
 448
 449         /* Parse octal numbers */
 450         i = strtol(value, &endptr, 8);
 451
 452         /* If not an octal number, maybe true/false? */
 453         if (*endptr != 0)
 454                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 455
 456         /*
 457          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 458          * a chmod value to restrict to.
 459          */
 460         switch (i) {
 461         case PERM_UMASK:               /* 0 */
 462                 return PERM_UMASK;
 463         case OLD_PERM_GROUP:           /* 1 */
 464                 return PERM_GROUP;
 465         case OLD_PERM_EVERYBODY:       /* 2 */
 466                 return PERM_EVERYBODY;
 467         }
 468
 469         /* A filemode value was given: 0xxx */
 470
 471         if ((i & 0600) != 0600)
 472                 die("Problem with core.sharedRepository filemode value "
 473                     "(0%.3o).\nThe owner of files must always have "
 474                     "read and write permissions.", i);
 475
 476         /*
 477          * Mask filemode value. Others can not get write permission.
 478          * x flags for directories are handled separately.
 479          */
 480         return -(i & 0666);
 481 }
 482
 483 int check_repository_format_version(const char *var, const char *value, void *cb)
 484 {
 485         if (strcmp(var, "core.repositoryformatversion") == 0)
 486                 repository_format_version = git_config_int(var, value);
 487         else if (strcmp(var, "core.sharedrepository") == 0)
 488                 shared_repository = git_config_perm(var, value);
 489         else if (strcmp(var, "core.bare") == 0) {
 490                 is_bare_repository_cfg = git_config_bool(var, value);
 491                 if (is_bare_repository_cfg == 1)
 492                         inside_work_tree = -1;
 493         } else if (strcmp(var, "core.worktree") == 0) {
 494                 if (!value)
 495                         return config_error_nonbool(var);
 496                 free(git_work_tree_cfg);
 497                 git_work_tree_cfg = xstrdup(value);
 498                 inside_work_tree = -1;
 499         }
 500         return 0;
 501 }
 502
 503 int check_repository_format(void)
 504 {
 505         return check_repository_format_gently(NULL);
 506 }
 507
 508 const char *setup_git_directory(void)
 509 {
 510         const char *retval = setup_git_directory_gently(NULL);
 511
 512         /* If the work tree is not the default one, recompute prefix */
 513         if (inside_work_tree < 0) {
 514                 static char buffer[PATH_MAX + 1];
 515                 char *rel;
 516                 if (retval && chdir(retval))
 517                         die_errno ("Could not jump back into original cwd");
 518                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 519                 if (rel && *rel && chdir(get_git_work_tree()))
 520                         die_errno ("Could not jump to working directory");
 521                 return rel && *rel ? strcat(rel, "/") : NULL;
 522         }
 523
 524         return retval;
 525 }