git-init: set core.worktree if GIT_WORK_TREE is specified

Now you can do the following to create a repository which
has a separate working tree:

    /tmp/foo$ export GIT_DIR=/tmp/bar
    /tmp/foo$ git --work-tree . init
    Initialized empty Git repository in /tmp/bar/
    /tmp/foo$ git config core.worktree
    /tmp/foo

Signed-off-by: Matthias Lederhofer <matled@gmx.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-init-db.c b/builtin-init-db.c
index d429ced..66ddaeb 100644 (file)
--- a/builtin-init-db.c
+++ b/builtin-init-db.c
@@ -174,7 +174,36 @@ static void copy_templates(const char *git_dir, int len, const char *template_di
        closedir(dir);
 }
 
-static int create_default_files(const char *git_dir, const char *template_path)
+/*
+ * Get the full path to the working tree specified in $GIT_WORK_TREE
+ * or NULL if no working tree is specified.
+ */
+static const char *get_work_tree(void)
+{
+       const char *git_work_tree;
+       char cwd[PATH_MAX];
+       static char worktree[PATH_MAX];
+
+       git_work_tree = getenv(GIT_WORK_TREE_ENVIRONMENT);
+       if (!git_work_tree)
+               return NULL;
+       if (!getcwd(cwd, sizeof(cwd)))
+               die("Unable to read current working directory");
+       if (chdir(git_work_tree))
+               die("Cannot change directory to specified working tree '%s'",
+                       git_work_tree);
+       if (git_work_tree[0] != '/') {
+               if (!getcwd(worktree, sizeof(worktree)))
+                       die("Unable to read current working directory");
+               git_work_tree = worktree;
+       }
+       if (chdir(cwd))
+               die("Cannot come back to cwd");
+       return git_work_tree;
+}
+
+static int create_default_files(const char *git_dir, const char *git_work_tree,
+       const char *template_path)
 {
        unsigned len = strlen(git_dir);
        static char path[PATH_MAX];
@@ -253,7 +282,7 @@ static int create_default_files(const char *git_dir, const char *template_path)
        }
        git_config_set("core.filemode", filemode ? "true" : "false");
 
-       if (is_bare_repository()) {
+       if (is_bare_repository() && !git_work_tree) {
                git_config_set("core.bare", "true");
        }
        else {
@@ -261,6 +290,8 @@ static int create_default_files(const char *git_dir, const char *template_path)
                /* allow template config file to override the default */
                if (log_all_ref_updates == -1)
                    git_config_set("core.logallrefupdates", "true");
+               if (git_work_tree)
+                       git_config_set("core.worktree", git_work_tree);
        }
        return reinit;
 }
@@ -277,6 +308,7 @@ static const char init_db_usage[] =
 int cmd_init_db(int argc, const char **argv, const char *prefix)
 {
        const char *git_dir;
+       const char *git_work_tree;
        const char *sha1_dir;
        const char *template_dir = NULL;
        char *path;
@@ -297,6 +329,8 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
                        usage(init_db_usage);
        }
 
+       git_work_tree = get_work_tree();
+
        /*
         * Set up the default .git directory contents
         */
@@ -312,7 +346,7 @@ int cmd_init_db(int argc, const char **argv, const char *prefix)
         */
        check_repository_format();
 
-       reinit = create_default_files(git_dir, template_dir);
+       reinit = create_default_files(git_dir, git_work_tree, template_dir);
 
        /*
         * And set up the object store.