git-branch: show detached HEAD

diff --git a/setup.c b/setup.c
index 4612f110ee0beaeada3cb31ce7d47ad7175eec9c..2ae57f7c94e304ef3468a27cd245c314a08046ed 100644 (file)
--- a/setup.c
+++ b/setup.c
@@ -131,28 +131,46 @@ const char **get_pathspec(const char *prefix, const char **pathspec)
 }
 
 /*
- * Test if it looks like we're at the top level git directory.
+ * Test if it looks like we're at a git directory.
  * We want to see:
  *
- *  - either a .git/objects/ directory _or_ the proper
+ *  - either a objects/ directory _or_ the proper
  *    GIT_OBJECT_DIRECTORY environment variable
- *  - a refs/ directory under ".git"
+ *  - a refs/ directory
  *  - either a HEAD symlink or a HEAD file that is formatted as
  *    a proper "ref:".
  */
-static int is_toplevel_directory(void)
+static int is_git_directory(const char *suspect)
 {
-       if (access(".git/refs/", X_OK) ||
-           access(getenv(DB_ENVIRONMENT) ?
-                  getenv(DB_ENVIRONMENT) : ".git/objects/", X_OK) ||
-           validate_symref(".git/HEAD"))
+       char path[PATH_MAX];
+       size_t len = strlen(suspect);
+
+       strcpy(path, suspect);
+       if (getenv(DB_ENVIRONMENT)) {
+               if (access(getenv(DB_ENVIRONMENT), X_OK))
+                       return 0;
+       }
+       else {
+               strcpy(path + len, "/objects");
+               if (access(path, X_OK))
+                       return 0;
+       }
+
+       strcpy(path + len, "/refs");
+       if (access(path, X_OK))
+               return 0;
+
+       strcpy(path + len, "/HEAD");
+       if (validate_symref(path))
                return 0;
+
        return 1;
 }
 
 const char *setup_git_directory_gently(int *nongit_ok)
 {
        static char cwd[PATH_MAX+1];
+       const char *gitdirenv;
        int len, offset;
 
        /*
@@ -160,32 +178,17 @@ const char *setup_git_directory_gently(int *nongit_ok)
         * to do any discovery, but we still do repository
         * validation.
         */
-       if (getenv(GIT_DIR_ENVIRONMENT)) {
-               char path[PATH_MAX];
-               int len = strlen(getenv(GIT_DIR_ENVIRONMENT));
-               if (sizeof(path) - 40 < len)
+       gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
+       if (gitdirenv) {
+               if (PATH_MAX - 40 < strlen(gitdirenv))
                        die("'$%s' too big", GIT_DIR_ENVIRONMENT);
-               memcpy(path, getenv(GIT_DIR_ENVIRONMENT), len);
-               
-               strcpy(path + len, "/refs");
-               if (access(path, X_OK))
-                       goto bad_dir_environ;
-               strcpy(path + len, "/HEAD");
-               if (validate_symref(path))
-                       goto bad_dir_environ;
-               if (getenv(DB_ENVIRONMENT)) {
-                       if (access(getenv(DB_ENVIRONMENT), X_OK))
-                               goto bad_dir_environ;
-               }
-               else {
-                       strcpy(path + len, "/objects");
-                       if (access(path, X_OK))
-                               goto bad_dir_environ;
+               if (is_git_directory(gitdirenv))
+                       return NULL;
+               if (nongit_ok) {
+                       *nongit_ok = 1;
+                       return NULL;
                }
-               return NULL;
-       bad_dir_environ:
-               path[len] = 0;
-               die("Not a git repository: '%s'", path);
+               die("Not a git repository: '%s'", gitdirenv);
        }
 
        if (!getcwd(cwd, sizeof(cwd)) || cwd[0] != '/')
@@ -193,11 +196,17 @@ const char *setup_git_directory_gently(int *nongit_ok)
 
        offset = len = strlen(cwd);
        for (;;) {
-               if (is_toplevel_directory())
+               if (is_git_directory(".git"))
                        break;
                chdir("..");
                do {
                        if (!offset) {
+                               if (is_git_directory(cwd)) {
+                                       if (chdir(cwd))
+                                               die("Cannot come back to cwd");
+                                       setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
+                                       return NULL;
+                               }
                                if (nongit_ok) {
                                        if (chdir(cwd))
                                                die("Cannot come back to cwd");