receive-pack: refactor updateInstead codepath

Keep the "there is nothing to update in a bare repository", "when
the check and update process runs, here are the GIT_DIR and
GIT_WORK_TREE" logic, which will be common regardless of how the
decision to update and the actual update are done, in the original
update_worktree() function, and split out the "working tree and
the index must match the original HEAD exactly" and "use two-way
read-tree to update the working tree" into a new push_to_deploy()
helper function.  This will allow customizing the logic more cleanly
and easily.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index c047418..11800cd 100644 (file)
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -733,7 +733,9 @@ static int update_shallow_ref(struct command *cmd, struct shallow_info *si)
        return 0;
 }
 
-static const char *update_worktree(unsigned char *sha1)
+static const char *push_to_deploy(unsigned char *sha1,
+                                 struct argv_array *env,
+                                 const char *work_tree)
 {
        const char *update_refresh[] = {
                "update-index", "-q", "--ignore-submodules", "--refresh", NULL
@@ -748,69 +750,70 @@ static const char *update_worktree(unsigned char *sha1)
        const char *read_tree[] = {
                "read-tree", "-u", "-m", NULL, NULL
        };
-       const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
-       struct argv_array env = ARGV_ARRAY_INIT;
        struct child_process child = CHILD_PROCESS_INIT;
 
-       if (is_bare_repository())
-               return "denyCurrentBranch = updateInstead needs a worktree";
-
-       argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
-
        child.argv = update_refresh;
-       child.env = env.argv;
+       child.env = env->argv;
        child.dir = work_tree;
        child.no_stdin = 1;
        child.stdout_to_stderr = 1;
        child.git_cmd = 1;
-       if (run_command(&child)) {
-               argv_array_clear(&env);
+       if (run_command(&child))
                return "Up-to-date check failed";
-       }
 
        /* run_command() does not clean up completely; reinitialize */
        child_process_init(&child);
        child.argv = diff_files;
-       child.env = env.argv;
+       child.env = env->argv;
        child.dir = work_tree;
        child.no_stdin = 1;
        child.stdout_to_stderr = 1;
        child.git_cmd = 1;
-       if (run_command(&child)) {
-               argv_array_clear(&env);
+       if (run_command(&child))
                return "Working directory has unstaged changes";
-       }
 
        child_process_init(&child);
        child.argv = diff_index;
-       child.env = env.argv;
+       child.env = env->argv;
        child.no_stdin = 1;
        child.no_stdout = 1;
        child.stdout_to_stderr = 0;
        child.git_cmd = 1;
-       if (run_command(&child)) {
-               argv_array_clear(&env);
+       if (run_command(&child))
                return "Working directory has staged changes";
-       }
 
        read_tree[3] = sha1_to_hex(sha1);
        child_process_init(&child);
        child.argv = read_tree;
-       child.env = env.argv;
+       child.env = env->argv;
        child.dir = work_tree;
        child.no_stdin = 1;
        child.no_stdout = 1;
        child.stdout_to_stderr = 0;
        child.git_cmd = 1;
-       if (run_command(&child)) {
-               argv_array_clear(&env);
+       if (run_command(&child))
                return "Could not update working tree to new HEAD";
-       }
 
-       argv_array_clear(&env);
        return NULL;
 }
 
+static const char *update_worktree(unsigned char *sha1)
+{
+       const char *retval;
+       const char *work_tree = git_work_tree_cfg ? git_work_tree_cfg : "..";
+       struct argv_array env = ARGV_ARRAY_INIT;
+
+       if (is_bare_repository())
+               return "denyCurrentBranch = updateInstead needs a worktree";
+
+       argv_array_pushf(&env, "GIT_DIR=%s", absolute_path(get_git_dir()));
+
+       retval = push_to_deploy(sha1, &env, work_tree);
+
+       argv_array_clear(&env);
+       return retval;
+}
+
 static const char *update(struct command *cmd, struct shallow_info *si)
 {
        const char *name = cmd->ref_name;