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 || is_absolute_path(arg))
  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 void setup_work_tree(void)
 244 {
 245         const char *work_tree, *git_dir;
 246         static int initialized = 0;
 247
 248         if (initialized)
 249                 return;
 250         work_tree = get_git_work_tree();
 251         git_dir = get_git_dir();
 252         if (!is_absolute_path(git_dir))
 253                 set_git_dir(make_absolute_path(git_dir));
 254         if (!work_tree || chdir(work_tree))
 255                 die("This operation must be run in a work tree");
 256         initialized = 1;
 257 }
 258
 259 /*
 260  * We cannot decide in this function whether we are in the work tree or
 261  * not, since the config can only be read _after_ this function was called.
 262  */
 263 const char *setup_git_directory_gently(int *nongit_ok)
 264 {
 265         const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
 266         static char cwd[PATH_MAX+1];
 267         const char *gitdirenv;
 268         int len, offset;
 269         int minoffset = 0;
 270
 271         /*
 272          * If GIT_DIR is set explicitly, we're not going
 273          * to do any discovery, but we still do repository
 274          * validation.
 275          */
 276         gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
 277         if (gitdirenv) {
 278                 if (PATH_MAX - 40 < strlen(gitdirenv))
 279                         die("'$%s' too big", GIT_DIR_ENVIRONMENT);
 280                 if (is_git_directory(gitdirenv)) {
 281                         static char buffer[1024 + 1];
 282                         const char *retval;
 283
 284                         if (!work_tree_env)
 285                                 return set_work_tree(gitdirenv);
 286                         retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
 287                                         get_git_work_tree());
 288                         if (!retval || !*retval)
 289                                 return NULL;
 290                         set_git_dir(make_absolute_path(gitdirenv));
 291                         if (chdir(work_tree_env) < 0)
 292                                 die ("Could not chdir to %s", work_tree_env);
 293                         strcat(buffer, "/");
 294                         return retval;
 295                 }
 296                 if (nongit_ok) {
 297                         *nongit_ok = 1;
 298                         return NULL;
 299                 }
 300                 die("Not a git repository: '%s'", gitdirenv);
 301         }
 302
 303         if (!getcwd(cwd, sizeof(cwd)-1))
 304                 die("Unable to read current working directory");
 305 #ifdef __MINGW32__
 306         if (cwd[1] == ':')
 307                 minoffset = 2;
 308 #endif
 309
 310         /*
 311          * Test in the following order (relative to the cwd):
 312          * - .git/
 313          * - ./ (bare)
 314          * - ../.git/
 315          * - ../ (bare)
 316          * - ../../.git/
 317          *   etc.
 318          */
 319         offset = len = strlen(cwd);
 320         for (;;) {
 321                 if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
 322                         break;
 323                 if (is_git_directory(".")) {
 324                         inside_git_dir = 1;
 325                         if (!work_tree_env)
 326                                 inside_work_tree = 0;
 327                         set_git_dir(".");
 328                         return NULL;
 329                 }
 330                 chdir("..");
 331                 do {
 332                         if (offset <= minoffset) {
 333                                 if (nongit_ok) {
 334                                         if (chdir(cwd))
 335                                                 die("Cannot come back to cwd");
 336                                         *nongit_ok = 1;
 337                                         return NULL;
 338                                 }
 339                                 die("Not a git repository");
 340                         }
 341                 } while (offset > minoffset && cwd[--offset] != '/');
 342         }
 343
 344         inside_git_dir = 0;
 345         if (!work_tree_env)
 346                 inside_work_tree = 1;
 347         git_work_tree_cfg = xstrndup(cwd, offset);
 348         if (offset == len)
 349                 return NULL;
 350
 351         /* Make "offset" point to past the '/', and add a '/' at the end */
 352         offset++;
 353         cwd[len++] = '/';
 354         cwd[len] = 0;
 355         return cwd + offset;
 356 }
 357
 358 int git_config_perm(const char *var, const char *value)
 359 {
 360         if (value) {
 361                 int i;
 362                 if (!strcmp(value, "umask"))
 363                         return PERM_UMASK;
 364                 if (!strcmp(value, "group"))
 365                         return PERM_GROUP;
 366                 if (!strcmp(value, "all") ||
 367                     !strcmp(value, "world") ||
 368                     !strcmp(value, "everybody"))
 369                         return PERM_EVERYBODY;
 370                 i = atoi(value);
 371                 if (i > 1)
 372                         return i;
 373         }
 374         return git_config_bool(var, value);
 375 }
 376
 377 int check_repository_format_version(const char *var, const char *value)
 378 {
 379         if (strcmp(var, "core.repositoryformatversion") == 0)
 380                 repository_format_version = git_config_int(var, value);
 381         else if (strcmp(var, "core.sharedrepository") == 0)
 382                 shared_repository = git_config_perm(var, value);
 383         else if (strcmp(var, "core.bare") == 0) {
 384                 is_bare_repository_cfg = git_config_bool(var, value);
 385                 if (is_bare_repository_cfg == 1)
 386                         inside_work_tree = -1;
 387         } else if (strcmp(var, "core.worktree") == 0) {
 388                 if (git_work_tree_cfg)
 389                         free(git_work_tree_cfg);
 390                 git_work_tree_cfg = xstrdup(value);
 391                 inside_work_tree = -1;
 392         }
 393         return 0;
 394 }
 395
 396 int check_repository_format(void)
 397 {
 398         git_config(check_repository_format_version);
 399         if (GIT_REPO_VERSION < repository_format_version)
 400                 die ("Expected git repo version <= %d, found %d",
 401                      GIT_REPO_VERSION, repository_format_version);
 402         return 0;
 403 }
 404
 405 const char *setup_git_directory(void)
 406 {
 407         const char *retval = setup_git_directory_gently(NULL);
 408         check_repository_format();
 409
 410         /* If the work tree is not the default one, recompute prefix */
 411         if (inside_work_tree < 0) {
 412                 static char buffer[PATH_MAX + 1];
 413                 char *rel;
 414                 if (retval && chdir(retval))
 415                         die ("Could not jump back into original cwd");
 416                 rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
 417                 return rel && *rel ? strcat(rel, "/") : NULL;
 418         }
 419
 420         return retval;
 421 }