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