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 static void NORETURN die_verify_filename(const char *prefix, const char *arg)
  81 {
  82         unsigned char sha1[20];
  83         unsigned mode;
  84         /* try a detailed diagnostic ... */
  85         get_sha1_with_mode_1(arg, sha1, &mode, 0, prefix);
  86         /* ... or fall back the most general message. */
  87         die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
  88             "Use '--' to separate paths from revisions", arg);
  89
  90 }
  91
  92 /*
  93  * Verify a filename that we got as an argument for a pathspec
  94  * entry. Note that a filename that begins with "-" never verifies
  95  * as true, because even if such a filename were to exist, we want
  96  * it to be preceded by the "--" marker (or we want the user to
  97  * use a format like "./-filename")
  98  */
  99 void verify_filename(const char *prefix, const char *arg)
 100 {
 101         if (*arg == '-')
 102                 die("bad flag '%s' used after filename", arg);
 103         if (check_filename(prefix, arg))
 104                 return;
 105         die_verify_filename(prefix, arg);
 106 }
 107
 108 /*
 109  * Opposite of the above: the command line did not have -- marker
 110  * and we parsed the arg as a refname.  It should not be interpretable
 111  * as a filename.
 112  */
 113 void verify_non_filename(const char *prefix, const char *arg)
 114 {
 115         if (!is_inside_work_tree() || is_inside_git_dir())
 116                 return;
 117         if (*arg == '-')
 118                 return; /* flag */
 119         if (!check_filename(prefix, arg))
 120                 return;
 121         die("ambiguous argument '%s': both revision and filename\n"
 122             "Use '--' to separate filenames from revisions", arg);
 123 }
 124
 125 const char **get_pathspec(const char *prefix, const char **pathspec)
 126 {
 127         const char *entry = *pathspec;
 128         const char **src, **dst;
 129         int prefixlen;
 130
 131         if (!prefix && !entry)
 132                 return NULL;
 133
 134         if (!entry) {
 135                 static const char *spec[2];
 136                 spec[0] = prefix;
 137                 spec[1] = NULL;
 138                 return spec;
 139         }
 140
 141         /* Otherwise we have to re-write the entries.. */
 142         src = pathspec;
 143         dst = pathspec;
 144         prefixlen = prefix ? strlen(prefix) : 0;
 145         while (*src) {
 146                 const char *p = prefix_path(prefix, prefixlen, *src);
 147                 *(dst++) = p;
 148                 src++;
 149         }
 150         *dst = NULL;
 151         if (!*pathspec)
 152                 return NULL;
 153         return pathspec;
 154 }
 155
 156 /*
 157  * Test if it looks like we're at a git directory.
 158  * We want to see:
 159  *
 160  *  - either an objects/ directory _or_ the proper
 161  *    GIT_OBJECT_DIRECTORY environment variable
 162  *  - a refs/ directory
 163  *  - either a HEAD symlink or a HEAD file that is formatted as
 164  *    a proper "ref:", or a regular file HEAD that has a properly
 165  *    formatted sha1 object name.
 166  */
 167 static int is_git_directory(const char *suspect)
 168 {
 169         char path[PATH_MAX];
 170         size_t len = strlen(suspect);
 171
 172         strcpy(path, suspect);
 173         if (getenv(DB_ENVIRONMENT)) {
 174                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 175                         return 0;
 176         }
 177         else {
 178                 strcpy(path + len, "/objects");
 179                 if (access(path, X_OK))
 180                         return 0;
 181         }
 182
 183         strcpy(path + len, "/refs");
 184         if (access(path, X_OK))
 185                 return 0;
 186
 187         strcpy(path + len, "/HEAD");
 188         if (validate_headref(path))
 189                 return 0;
 190
 191         return 1;
 192 }
 193
 194 int is_inside_git_dir(void)
 195 {
 196         if (inside_git_dir < 0)
 197                 inside_git_dir = is_inside_dir(get_git_dir());
 198         return inside_git_dir;
 199 }
 200
 201 int is_inside_work_tree(void)
 202 {
 203         if (inside_work_tree < 0)
 204                 inside_work_tree = is_inside_dir(get_git_work_tree());
 205         return inside_work_tree;
 206 }
 207
 208 /*
 209  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 210  * The old behaviour (which we retain here) is to set the work tree root
 211  * to the cwd, unless overridden by the config, the command line, or
 212  * GIT_WORK_TREE.
 213  */
 214 static const char *set_work_tree(const char *dir)
 215 {
 216         char buffer[PATH_MAX + 1];
 217
 218         if (!getcwd(buffer, sizeof(buffer)))
 219                 die ("Could not get the current working directory");
 220         git_work_tree_cfg = xstrdup(buffer);
 221         inside_work_tree = 1;
 222
 223         return NULL;
 224 }
 225
 226 void setup_work_tree(void)
 227 {
 228         const char *work_tree, *git_dir;
 229         static int initialized = 0;
 230
 231         if (initialized)
 232                 return;
 233         work_tree = get_git_work_tree();
 234         git_dir = get_git_dir();
 235         if (!is_absolute_path(git_dir))
 236                 git_dir = make_absolute_path(git_dir);
 237         if (!work_tree || chdir(work_tree))
 238                 die("This operation must be run in a work tree");
 239         set_git_dir(make_relative_path(git_dir, work_tree));
 240         initialized = 1;
 241 }
 242
 243 static int check_repository_format_gently(int *nongit_ok)
 244 {
 245         git_config(check_repository_format_version, NULL);
 246         if (GIT_REPO_VERSION < repository_format_version) {
 247                 if (!nongit_ok)
 248                         die ("Expected git repo version <= %d, found %d",
 249                              GIT_REPO_VERSION, repository_format_version);
 250                 warning("Expected git repo version <= %d, found %d",
 251                         GIT_REPO_VERSION, repository_format_version);
 252                 warning("Please upgrade Git");
 253                 *nongit_ok = -1;
 254                 return -1;
 255         }
 256         return 0;
 257 }
 258
 259 /*
 260  * Try to read the location of the git directory from the .git file,
 261  * return path to git directory if found.
 262  */
 263 const char *read_gitfile_gently(const char *path)
 264 {
 265         char *buf;
 266         struct stat st;
 267         int fd;
 268         size_t len;
 269
 270         if (stat(path, &st))
 271                 return NULL;
 272         if (!S_ISREG(st.st_mode))
 273                 return NULL;
 274         fd = open(path, O_RDONLY);
 275         if (fd < 0)
 276                 die_errno("Error opening '%s'", path);
 277         buf = xmalloc(st.st_size + 1);
 278         len = read_in_full(fd, buf, st.st_size);
 279         close(fd);
 280         if (len != st.st_size)
 281                 die("Error reading %s", path);
 282         buf[len] = '\0';
 283         if (prefixcmp(buf, "gitdir: "))
 284                 die("Invalid gitfile format: %s", path);
 285         while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
 286                 len--;
 287         if (len < 9)
 288                 die("No path in gitfile: %s", path);
 289         buf[len] = '\0';
 290         if (!is_git_directory(buf + 8))
 291                 die("Not a git repository: %s", buf + 8);
 292         path = make_absolute_path(buf + 8);
 293         free(buf);
 294         return path;
 295 }
 296
 297 /*
 298  * We cannot decide in this function whether we are in the work tree or
 299  * not, since the config can only be read _after_ this function was called.
 300  */
 301 const char *setup_git_directory_gently(int *nongit_ok)
 302 {
 303         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 304         const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
 305         static char cwd[PATH_MAX+1];
 306         const char *gitdirenv;
 307         const char *gitfile_dir;
 308         int len, offset, ceil_offset;
 309
 310         /*
 311          * Let's assume that we are in a git repository.
 312          * If it turns out later that we are somewhere else, the value will be
 313          * updated accordingly.
 314          */
 315         if (nongit_ok)
 316                 *nongit_ok = 0;
 317
 318         /*
 319          * If GIT_DIR is set explicitly, we're not going
 320          * to do any discovery, but we still do repository
 321          * validation.
 322          */
 323         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 324         if (gitdirenv) {
 325                 if (PATH_MAX - 40 < strlen(gitdirenv))
 326                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 327                 if (is_git_directory(gitdirenv)) {
 328                         static char buffer[1024 + 1];
 329                         const char *retval;
 330
 331                         if (!work_tree_env) {
 332                                 retval = set_work_tree(gitdirenv);
 333                                 /* config may override worktree */
 334                                 if (check_repository_format_gently(nongit_ok))
 335                                         return NULL;
 336                                 return retval;
 337                         }
 338                         if (check_repository_format_gently(nongit_ok))
 339                                 return NULL;
 340                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 341                                         get_git_work_tree());
 342                         if (!retval || !*retval)
 343                                 return NULL;
 344                         set_git_dir(make_absolute_path(gitdirenv));
 345                         if (chdir(work_tree_env) < 0)
 346                                 die_errno ("Could not chdir to '%s'", work_tree_env);
 347                         strcat(buffer, "/");
 348                         return retval;
 349                 }
 350                 if (nongit_ok) {
 351                         *nongit_ok = 1;
 352                         return NULL;
 353                 }
 354                 die("Not a git repository: '%s'", gitdirenv);
 355         }
 356
 357         if (!getcwd(cwd, sizeof(cwd)-1))
 358                 die_errno("Unable to read current working directory");
 359
 360         ceil_offset = longest_ancestor_length(cwd, env_ceiling_dirs);
 361         if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
 362                 ceil_offset = 1;
 363
 364         /*
 365          * Test in the following order (relative to the cwd):
 366          * - .git (file containing "gitdir: <path>")
 367          * - .git/
 368          * - ./ (bare)
 369          * - ../.git
 370          * - ../.git/
 371          * - ../ (bare)
 372          * - ../../.git/
 373          *   etc.
 374          */
 375         offset = len = strlen(cwd);
 376         for (;;) {
 377                 gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
 378                 if (gitfile_dir) {
 379                         if (set_git_dir(gitfile_dir))
 380                                 die("Repository setup failed");
 381                         break;
 382                 }
 383                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 384                         break;
 385                 if (is_git_directory(".")) {
 386                         inside_git_dir = 1;
 387                         if (!work_tree_env)
 388                                 inside_work_tree = 0;
 389                         if (offset != len) {
 390                                 cwd[offset] = '\0';
 391                                 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
 392                         } else
 393                                 setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 394                         check_repository_format_gently(nongit_ok);
 395                         return NULL;
 396                 }
 397                 while (--offset > ceil_offset && cwd[offset] != '/');
 398                 if (offset <= ceil_offset) {
 399                         if (nongit_ok) {
 400                                 if (chdir(cwd))
 401                                         die_errno("Cannot come back to cwd");
 402                                 *nongit_ok = 1;
 403                                 return NULL;
 404                         }
 405                         die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 406                 }
 407                 if (chdir(".."))
 408                         die_errno("Cannot change to '%s/..'", cwd);
 409         }
 410
 411         inside_git_dir = 0;
 412         if (!work_tree_env)
 413                 inside_work_tree = 1;
 414         git_work_tree_cfg = xstrndup(cwd, offset);
 415         if (check_repository_format_gently(nongit_ok))
 416                 return NULL;
 417         if (offset == len)
 418                 return NULL;
 419
 420         /* Make "offset" point to past the '/', and add a '/' at the end */
 421         offset++;
 422         cwd[len++] = '/';
 423         cwd[len] = 0;
 424         return cwd + offset;
 425 }
 426
 427 int git_config_perm(const char *var, const char *value)
 428 {
 429         int i;
 430         char *endptr;
 431
 432         if (value == NULL)
 433                 return PERM_GROUP;
 434
 435         if (!strcmp(value, "umask"))
 436                 return PERM_UMASK;
 437         if (!strcmp(value, "group"))
 438                 return PERM_GROUP;
 439         if (!strcmp(value, "all") ||
 440             !strcmp(value, "world") ||
 441             !strcmp(value, "everybody"))
 442                 return PERM_EVERYBODY;
 443
 444         /* Parse octal numbers */
 445         i = strtol(value, &endptr, 8);
 446
 447         /* If not an octal number, maybe true/false? */
 448         if (*endptr != 0)
 449                 return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
 450
 451         /*
 452          * Treat values 0, 1 and 2 as compatibility cases, otherwise it is
 453          * a chmod value to restrict to.
 454          */
 455         switch (i) {
 456         case PERM_UMASK:               /* 0 */
 457                 return PERM_UMASK;
 458         case OLD_PERM_GROUP:           /* 1 */
 459                 return PERM_GROUP;
 460         case OLD_PERM_EVERYBODY:       /* 2 */
 461                 return PERM_EVERYBODY;
 462         }
 463
 464         /* A filemode value was given: 0xxx */
 465
 466         if ((i & 0600) != 0600)
 467                 die("Problem with core.sharedRepository filemode value "
 468                     "(0%.3o).\nThe owner of files must always have "
 469                     "read and write permissions.", i);
 470
 471         /*
 472          * Mask filemode value. Others can not get write permission.
 473          * x flags for directories are handled separately.
 474          */
 475         return -(i & 0666);
 476 }
 477
 478 int check_repository_format_version(const char *var, const char *value, void *cb)
 479 {
 480         if (strcmp(var, "core.repositoryformatversion") == 0)
 481                 repository_format_version = git_config_int(var, value);
 482         else if (strcmp(var, "core.sharedrepository") == 0)
 483                 shared_repository = git_config_perm(var, value);
 484         else if (strcmp(var, "core.bare") == 0) {
 485                 is_bare_repository_cfg = git_config_bool(var, value);
 486                 if (is_bare_repository_cfg == 1)
 487                         inside_work_tree = -1;
 488         } else if (strcmp(var, "core.worktree") == 0) {
 489                 if (!value)
 490                         return config_error_nonbool(var);
 491                 free(git_work_tree_cfg);
 492                 git_work_tree_cfg = xstrdup(value);
 493                 inside_work_tree = -1;
 494         }
 495         return 0;
 496 }
 497
 498 int check_repository_format(void)
 499 {
 500         return check_repository_format_gently(NULL);
 501 }
 502
 503 const char *setup_git_directory(void)
 504 {
 505         const char *retval = setup_git_directory_gently(NULL);
 506
 507         /* If the work tree is not the default one, recompute prefix */
 508         if (inside_work_tree < 0) {
 509                 static char buffer[PATH_MAX + 1];
 510                 char *rel;
 511                 if (retval && chdir(retval))
 512                         die_errno ("Could not jump back into original cwd");
 513                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 514                 if (rel && *rel && chdir(get_git_work_tree()))
 515                         die_errno ("Could not jump to working directory");
 516                 return rel && *rel ? strcat(rel, "/") : NULL;
 517         }
 518
 519         return retval;
 520 }