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