setup: split off a function to checks working dir for .git file

diff --git a/setup.c b/setup.c
index 0e4cfe603f1afe515365c9daf1ad8406de8e7fa8..3d25d0f205ba7ad555a7f26e40be7590ac16d926 100644 (file)
--- a/setup.c
+++ b/setup.c
@@ -170,6 +170,8 @@ static int is_git_directory(const char *suspect)
        char path[PATH_MAX];
        size_t len = strlen(suspect);
 
+       if (PATH_MAX <= len + strlen("/objects"))
+               die("Too long path: %.*s", 60, suspect);
        strcpy(path, suspect);
        if (getenv(DB_ENVIRONMENT)) {
                if (access(getenv(DB_ENVIRONMENT), X_OK))
@@ -311,6 +313,53 @@ const char *read_gitfile_gently(const char *path)
        return path;
 }
 
+static const char *setup_explicit_git_dir(const char *gitdirenv,
+                               const char *work_tree_env, int *nongit_ok)
+{
+       static char buffer[1024 + 1];
+       const char *retval;
+
+       if (PATH_MAX - 40 < strlen(gitdirenv))
+               die("'$%s' too big", GIT_DIR_ENVIRONMENT);
+       if (!is_git_directory(gitdirenv)) {
+               if (nongit_ok) {
+                       *nongit_ok = 1;
+                       return NULL;
+               }
+               die("Not a git repository: '%s'", gitdirenv);
+       }
+       if (!work_tree_env) {
+               retval = set_work_tree(gitdirenv);
+               /* config may override worktree */
+               if (check_repository_format_gently(nongit_ok))
+                       return NULL;
+               return retval;
+       }
+       if (check_repository_format_gently(nongit_ok))
+               return NULL;
+       retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
+                       get_git_work_tree());
+       if (!retval || !*retval)
+               return NULL;
+       set_git_dir(make_absolute_path(gitdirenv));
+       if (chdir(work_tree_env) < 0)
+               die_errno ("Could not chdir to '%s'", work_tree_env);
+       strcat(buffer, "/");
+       return retval;
+}
+
+static int cwd_contains_git_dir(const char **gitfile_dirp)
+{
+       const char *gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
+       *gitfile_dirp = gitfile_dir;
+       if (gitfile_dir) {
+               if (set_git_dir(gitfile_dir))
+                       die("Repository setup failed");
+               return 1;
+       }
+       return is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT);
+}
+
 /*
  * We cannot decide in this function whether we are in the work tree or
  * not, since the config can only be read _after_ this function was called.
@@ -323,6 +372,9 @@ const char *setup_git_directory_gently(int *nongit_ok)
        const char *gitdirenv;
        const char *gitfile_dir;
        int len, offset, ceil_offset, root_len;
+       dev_t current_device = 0;
+       int one_filesystem = 1;
+       struct stat buf;
 
        /*
         * Let's assume that we are in a git repository.
@@ -338,38 +390,8 @@ const char *setup_git_directory_gently(int *nongit_ok)
         * validation.
         */
        gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
-       if (gitdirenv) {
-               if (PATH_MAX - 40 < strlen(gitdirenv))
-                       die("'$%s' too big", GIT_DIR_ENVIRONMENT);
-               if (is_git_directory(gitdirenv)) {
-                       static char buffer[1024 + 1];
-                       const char *retval;
-
-                       if (!work_tree_env) {
-                               retval = set_work_tree(gitdirenv);
-                               /* config may override worktree */
-                               if (check_repository_format_gently(nongit_ok))
-                                       return NULL;
-                               return retval;
-                       }
-                       if (check_repository_format_gently(nongit_ok))
-                               return NULL;
-                       retval = get_relative_cwd(buffer, sizeof(buffer) - 1,
-                                       get_git_work_tree());
-                       if (!retval || !*retval)
-                               return NULL;
-                       set_git_dir(make_absolute_path(gitdirenv));
-                       if (chdir(work_tree_env) < 0)
-                               die_errno ("Could not chdir to '%s'", work_tree_env);
-                       strcat(buffer, "/");
-                       return retval;
-               }
-               if (nongit_ok) {
-                       *nongit_ok = 1;
-                       return NULL;
-               }
-               die("Not a git repository: '%s'", gitdirenv);
-       }
+       if (gitdirenv)
+               return setup_explicit_git_dir(gitdirenv, work_tree_env, nongit_ok);
 
        if (!getcwd(cwd, sizeof(cwd)-1))
                die_errno("Unable to read current working directory");
@@ -390,14 +412,14 @@ const char *setup_git_directory_gently(int *nongit_ok)
         *   etc.
         */
        offset = len = strlen(cwd);
+       one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
+       if (one_filesystem) {
+               if (stat(".", &buf))
+                       die_errno("failed to stat '.'");
+               current_device = buf.st_dev;
+       }
        for (;;) {
-               gitfile_dir = read_gitfile_gently(DEFAULT_GIT_DIR_ENVIRONMENT);
-               if (gitfile_dir) {
-                       if (set_git_dir(gitfile_dir))
-                               die("Repository setup failed");
-                       break;
-               }
-               if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
+               if (cwd_contains_git_dir(&gitfile_dir))
                        break;
                if (is_git_directory(".")) {
                        inside_git_dir = 1;
@@ -422,8 +444,27 @@ const char *setup_git_directory_gently(int *nongit_ok)
                        }
                        die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
                }
-               if (chdir(".."))
+               if (one_filesystem) {
+                       if (stat("..", &buf)) {
+                               cwd[offset] = '\0';
+                               die_errno("failed to stat '%s/..'", cwd);
+                       }
+                       if (buf.st_dev != current_device) {
+                               if (nongit_ok) {
+                                       if (chdir(cwd))
+                                               die_errno("Cannot come back to cwd");
+                                       *nongit_ok = 1;
+                                       return NULL;
+                               }
+                               cwd[offset] = '\0';
+                               die("Not a git repository (or any parent up to mount parent %s)\n"
+                               "Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
+                       }
+               }
+               if (chdir("..")) {
+                       cwd[offset] = '\0';
                        die_errno("Cannot change to '%s/..'", cwd);
+               }
        }
 
        inside_git_dir = 0;