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 #ifdef __MINGW32__
   8 static inline int is_dir_sep(char c) { return c == '/' || c == '\\'; }
   9 #else
  10 static inline int is_dir_sep(char c) { return c == '/'; }
  11 #endif
  12
  13 const char *prefix_path(const char *prefix, int len, const char *path)
  14 {
  15         const char *orig = path;
  16         int do_pfx;
  17         for (;;) {
  18                 char c;
  19                 if (*path != '.')
  20                         break;
  21                 c = path[1];
  22                 /* "." */
  23                 if (!c) {
  24                         path++;
  25                         break;
  26                 }
  27                 /* "./" */
  28                 if (is_dir_sep(c)) {
  29                         path += 2;
  30                         continue;
  31                 }
  32                 if (c != '.')
  33                         break;
  34                 c = path[2];
  35                 if (!c)
  36                         path += 2;
  37                 else if (is_dir_sep(c))
  38                         path += 3;
  39                 else
  40                         break;
  41                 /* ".." and "../" */
  42                 /* Remove last component of the prefix */
  43                 do {
  44                         if (!len)
  45                                 die("'%s' is outside repository", orig);
  46                         len--;
  47                 } while (len && !is_dir_sep(prefix[len-1]));
  48                 continue;
  49         }
  50         do_pfx = len;
  51 #ifdef __MINGW32__
  52         /* we want to convert '\' in path to '/' (prefix already has '/') */
  53         {
  54                 const char *p = path;
  55                 while (!do_pfx && *p) {
  56                         do_pfx = *p++ == '\\';
  57                 }
  58         }
  59 #endif
  60         if (do_pfx) {
  61                 int speclen = strlen(path);
  62                 char *n = xmalloc(speclen + len + 1);
  63                 char *p;
  64
  65                 memcpy(n, prefix, len);
  66                 memcpy(n + len, path, speclen+1);
  67 #ifdef __MINGW32__
  68                 for (p = n + len; *p; p++)
  69                         if (*p == '\\')
  70                                 *p = '/';
  71 #endif
  72                 path = n;
  73         }
  74         return path;
  75 }
  76
  77 /*
  78  * Unlike prefix_path, this should be used if the named file does
  79  * not have to interact with index entry; i.e. name of a random file
  80  * on the filesystem.
  81  */
  82 const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
  83 {
  84         static char path[PATH_MAX];
  85 #ifndef __MINGW32__
  86         if (!pfx || !*pfx || is_absolute_path(arg))
  87                 return arg;
  88         memcpy(path, pfx, pfx_len);
  89         strcpy(path + pfx_len, arg);
  90 #else
  91         char *p;
  92         /* don't add prefix to absolute paths, but still replace '\' by '/' */
  93         if (is_absolute_path(arg))
  94                 pfx_len = 0;
  95         else
  96                 memcpy(path, pfx, pfx_len);
  97         strcpy(path + pfx_len, arg);
  98         for (p = path + pfx_len; *p; p++)
  99                 if (*p == '\\')
 100                         *p = '/';
 101 #endif
 102         return path;
 103 }
 104
 105 /*
 106  * Verify a filename that we got as an argument for a pathspec
 107  * entry. Note that a filename that begins with "-" never verifies
 108  * as true, because even if such a filename were to exist, we want
 109  * it to be preceded by the "--" marker (or we want the user to
 110  * use a format like "./-filename")
 111  */
 112 void verify_filename(const char *prefix, const char *arg)
 113 {
 114         const char *name;
 115         struct stat st;
 116
 117         if (*arg == '-')
 118                 die("bad flag '%s' used after filename", arg);
 119         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
 120         if (!lstat(name, &st))
 121                 return;
 122         if (errno == ENOENT)
 123                 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
 124                     "Use '--' to separate paths from revisions", arg);
 125         die("'%s': %s", arg, strerror(errno));
 126 }
 127
 128 /*
 129  * Opposite of the above: the command line did not have -- marker
 130  * and we parsed the arg as a refname.  It should not be interpretable
 131  * as a filename.
 132  */
 133 void verify_non_filename(const char *prefix, const char *arg)
 134 {
 135         const char *name;
 136         struct stat st;
 137
 138         if (!is_inside_work_tree() || is_inside_git_dir())
 139                 return;
 140         if (*arg == '-')
 141                 return; /* flag */
 142         name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
 143         if (!lstat(name, &st))
 144                 die("ambiguous argument '%s': both revision and filename\n"
 145                     "Use '--' to separate filenames from revisions", arg);
 146         if (errno != ENOENT && errno != ENOTDIR)
 147                 die("'%s': %s", arg, strerror(errno));
 148 }
 149
 150 const char **get_pathspec(const char *prefix, const char **pathspec)
 151 {
 152         const char *entry = *pathspec;
 153         const char **p;
 154         int prefixlen;
 155
 156         if (!prefix && !entry)
 157                 return NULL;
 158
 159         if (!entry) {
 160                 static const char *spec[2];
 161                 spec[0] = prefix;
 162                 spec[1] = NULL;
 163                 return spec;
 164         }
 165
 166         /* Otherwise we have to re-write the entries.. */
 167         p = pathspec;
 168         prefixlen = prefix ? strlen(prefix) : 0;
 169         do {
 170                 *p = prefix_path(prefix, prefixlen, entry);
 171         } while ((entry = *++p) != NULL);
 172         return (const char **) pathspec;
 173 }
 174
 175 /*
 176  * Test if it looks like we're at a git directory.
 177  * We want to see:
 178  *
 179  *  - either a objects/ directory _or_ the proper
 180  *    GIT_OBJECT_DIRECTORY environment variable
 181  *  - a refs/ directory
 182  *  - either a HEAD symlink or a HEAD file that is formatted as
 183  *    a proper "ref:", or a regular file HEAD that has a properly
 184  *    formatted sha1 object name.
 185  */
 186 static int is_git_directory(const char *suspect)
 187 {
 188         char path[PATH_MAX];
 189         size_t len = strlen(suspect);
 190
 191         strcpy(path, suspect);
 192         if (getenv(DB_ENVIRONMENT)) {
 193                 if (access(getenv(DB_ENVIRONMENT), X_OK))
 194                         return 0;
 195         }
 196         else {
 197                 strcpy(path + len, "/objects");
 198                 if (access(path, X_OK))
 199                         return 0;
 200         }
 201
 202         strcpy(path + len, "/refs");
 203         if (access(path, X_OK))
 204                 return 0;
 205
 206         strcpy(path + len, "/HEAD");
 207         if (validate_headref(path))
 208                 return 0;
 209
 210         return 1;
 211 }
 212
 213 int is_inside_git_dir(void)
 214 {
 215         if (inside_git_dir < 0)
 216                 inside_git_dir = is_inside_dir(get_git_dir());
 217         return inside_git_dir;
 218 }
 219
 220 int is_inside_work_tree(void)
 221 {
 222         if (inside_work_tree < 0)
 223                 inside_work_tree = is_inside_dir(get_git_work_tree());
 224         return inside_work_tree;
 225 }
 226
 227 /*
 228  * set_work_tree() is only ever called if you set GIT_DIR explicitely.
 229  * The old behaviour (which we retain here) is to set the work tree root
 230  * to the cwd, unless overridden by the config, the command line, or
 231  * GIT_WORK_TREE.
 232  */
 233 static const char *set_work_tree(const char *dir)
 234 {
 235         char buffer[PATH_MAX + 1];
 236
 237         if (!getcwd(buffer, sizeof(buffer)))
 238                 die ("Could not get the current working directory");
 239         git_work_tree_cfg = xstrdup(buffer);
 240         inside_work_tree = 1;
 241
 242         return NULL;
 243 }
 244
 245 void setup_work_tree(void)
 246 {
 247         const char *work_tree, *git_dir;
 248         static int initialized = 0;
 249
 250         if (initialized)
 251                 return;
 252         work_tree = get_git_work_tree();
 253         git_dir = get_git_dir();
 254         if (!is_absolute_path(git_dir))
 255                 set_git_dir(make_absolute_path(git_dir));
 256         if (!work_tree || chdir(work_tree))
 257                 die("This operation must be run in a work tree");
 258         initialized = 1;
 259 }
 260
 261 static int check_repository_format_gently(int *nongit_ok)
 262 {
 263         git_config(check_repository_format_version);
 264         if (GIT_REPO_VERSION < repository_format_version) {
 265                 if (!nongit_ok)
 266                         die ("Expected git repo version <= %d, found %d",
 267                              GIT_REPO_VERSION, repository_format_version);
 268                 warning("Expected git repo version <= %d, found %d",
 269                         GIT_REPO_VERSION, repository_format_version);
 270                 warning("Please upgrade Git");
 271                 *nongit_ok = -1;
 272                 return -1;
 273         }
 274         return 0;
 275 }
 276
 277 /*
 278  * We cannot decide in this function whether we are in the work tree or
 279  * not, since the config can only be read _after_ this function was called.
 280  */
 281 const char *setup_git_directory_gently(int *nongit_ok)
 282 {
 283         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 284         static char cwd[PATH_MAX+1];
 285         const char *gitdirenv;
 286         int len, offset;
 287         int minoffset = 0;
 288
 289         /*
 290          * If GIT_DIR is set explicitly, we're not going
 291          * to do any discovery, but we still do repository
 292          * validation.
 293          */
 294         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 295         if (gitdirenv) {
 296                 if (PATH_MAX - 40 < strlen(gitdirenv))
 297                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 298                 if (is_git_directory(gitdirenv)) {
 299                         static char buffer[1024 + 1];
 300                         const char *retval;
 301
 302                         if (!work_tree_env) {
 303                                 retval = set_work_tree(gitdirenv);
 304                                 /* config may override worktree */
 305                                 if (check_repository_format_gently(nongit_ok))
 306                                         return NULL;
 307                                 return retval;
 308                         }
 309                         if (check_repository_format_gently(nongit_ok))
 310                                 return NULL;
 311                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 312                                         get_git_work_tree());
 313                         if (!retval || !*retval)
 314                                 return NULL;
 315                         set_git_dir(make_absolute_path(gitdirenv));
 316                         if (chdir(work_tree_env) < 0)
 317                                 die ("Could not chdir to %s", work_tree_env);
 318                         strcat(buffer, "/");
 319                         return retval;
 320                 }
 321                 if (nongit_ok) {
 322                         *nongit_ok = 1;
 323                         return NULL;
 324                 }
 325                 die("Not a git repository: '%s'", gitdirenv);
 326         }
 327
 328         if (!getcwd(cwd, sizeof(cwd)-1))
 329                 die("Unable to read current working directory");
 330 #ifdef __MINGW32__
 331         if (cwd[1] == ':')
 332                 minoffset = 2;
 333 #endif
 334
 335         /*
 336          * Test in the following order (relative to the cwd):
 337          * - .git/
 338          * - ./ (bare)
 339          * - ../.git/
 340          * - ../ (bare)
 341          * - ../../.git/
 342          *   etc.
 343          */
 344         offset = len = strlen(cwd);
 345         for (;;) {
 346                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 347                         break;
 348                 if (is_git_directory(".")) {
 349                         inside_git_dir = 1;
 350                         if (!work_tree_env)
 351                                 inside_work_tree = 0;
 352                         setenv(GIT_DIR_ENVIRONMENT, ".", 1);
 353                         check_repository_format_gently(nongit_ok);
 354                         return NULL;
 355                 }
 356                 chdir("..");
 357                 do {
 358                         if (offset <= minoffset) {
 359                                 if (nongit_ok) {
 360                                         if (chdir(cwd))
 361                                                 die("Cannot come back to cwd");
 362                                         *nongit_ok = 1;
 363                                         return NULL;
 364                                 }
 365                                 die("Not a git repository");
 366                         }
 367                 } while (offset > minoffset && cwd[--offset] != '/');
 368         }
 369
 370         inside_git_dir = 0;
 371         if (!work_tree_env)
 372                 inside_work_tree = 1;
 373         git_work_tree_cfg = xstrndup(cwd, offset);
 374         if (check_repository_format_gently(nongit_ok))
 375                 return NULL;
 376         if (offset == len)
 377                 return NULL;
 378
 379         /* Make "offset" point to past the '/', and add a '/' at the end */
 380         offset++;
 381         cwd[len++] = '/';
 382         cwd[len] = 0;
 383         return cwd + offset;
 384 }
 385
 386 int git_config_perm(const char *var, const char *value)
 387 {
 388         if (value) {
 389                 int i;
 390                 if (!strcmp(value, "umask"))
 391                         return PERM_UMASK;
 392                 if (!strcmp(value, "group"))
 393                         return PERM_GROUP;
 394                 if (!strcmp(value, "all") ||
 395                     !strcmp(value, "world") ||
 396                     !strcmp(value, "everybody"))
 397                         return PERM_EVERYBODY;
 398                 i = atoi(value);
 399                 if (i > 1)
 400                         return i;
 401         }
 402         return git_config_bool(var, value);
 403 }
 404
 405 int check_repository_format_version(const char *var, const char *value)
 406 {
 407         if (strcmp(var, "core.repositoryformatversion") == 0)
 408                 repository_format_version = git_config_int(var, value);
 409         else if (strcmp(var, "core.sharedrepository") == 0)
 410                 shared_repository = git_config_perm(var, value);
 411         else if (strcmp(var, "core.bare") == 0) {
 412                 is_bare_repository_cfg = git_config_bool(var, value);
 413                 if (is_bare_repository_cfg == 1)
 414                         inside_work_tree = -1;
 415         } else if (strcmp(var, "core.worktree") == 0) {
 416                 if (git_work_tree_cfg)
 417                         free(git_work_tree_cfg);
 418                 git_work_tree_cfg = xstrdup(value);
 419                 inside_work_tree = -1;
 420         }
 421         return 0;
 422 }
 423
 424 int check_repository_format(void)
 425 {
 426         return check_repository_format_gently(NULL);
 427 }
 428
 429 const char *setup_git_directory(void)
 430 {
 431         const char *retval = setup_git_directory_gently(NULL);
 432
 433         /* If the work tree is not the default one, recompute prefix */
 434         if (inside_work_tree < 0) {
 435                 static char buffer[PATH_MAX + 1];
 436                 char *rel;
 437                 if (retval && chdir(retval))
 438                         die ("Could not jump back into original cwd");
 439                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 440                 return rel && *rel ? strcat(rel, "/") : NULL;
 441         }
 442
 443         return retval;
 444 }