In later patches we introduce the options and flag for commands
that modify the working directory, e.g. git-checkout.
This piece of code will be used universally for
all these working tree modifications as it
* supports dry run to answer the question:
"Is it safe to change the submodule to this new state?"
e.g. is it overwriting untracked files or are there local
changes that would be overwritten?
* supports a force flag that can be used for resetting
the tree.
Signed-off-by: Stefan Beller <sbeller@xxxxxxxxxx>
---
submodule.c | 135 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
submodule.h | 7 ++++
2 files changed, 142 insertions(+)
diff --git a/submodule.c b/submodule.c
index 0b2596e88a..bc5fecf8c5 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1239,6 +1239,141 @@ int bad_to_remove_submodule(const char *path, unsigned flags)
return ret;
}
+static int submodule_has_dirty_index(const struct submodule *sub)
+{
+ struct child_process cp = CHILD_PROCESS_INIT;
+
+ prepare_submodule_repo_env_no_git_dir(&cp.env_array);
+
+ cp.git_cmd = 1;
+ argv_array_pushl(&cp.args, "diff-index", "--quiet", \
+ "--cached", "HEAD", NULL);
+ cp.no_stdin = 1;
+ cp.no_stdout = 1;
+ cp.dir = sub->path;
+ if (start_command(&cp))
+ die("could not recurse into submodule '%s'", sub->path);
+
+ return finish_command(&cp);
+}
+
+static void submodule_reset_index(const char *path)
+{
+ struct child_process cp = CHILD_PROCESS_INIT;
+ prepare_submodule_repo_env_no_git_dir(&cp.env_array);
+
+ cp.git_cmd = 1;
+ cp.no_stdin = 1;
+ cp.dir = path;
+
+ argv_array_pushf(&cp.args, "--super-prefix=%s/", path);
+ argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
+
+ argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
+
+ if (run_command(&cp))
+ die("could not reset submodule index");
+}
+
+/**
+ * Moves a submodule at a given path from a given head to another new head.
+ * For edge cases (a submodule coming into existence or removing a submodule)
+ * pass NULL for old or new respectively.
+ */
+int submodule_move_head(const char *path,
+ const char *old,
+ const char *new,
+ unsigned flags)
+{
+ int ret = 0;
+ struct child_process cp = CHILD_PROCESS_INIT;
+ const struct submodule *sub;
+
+ sub = submodule_from_path(null_sha1, path);
+
+ if (!sub)
+ die("BUG: could not get submodule information for '%s'", path);
+
+ if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
+ /* Check if the submodule has a dirty index. */
+ if (submodule_has_dirty_index(sub))
+ return error(_("submodule '%s' has dirty index"), path);
+ }
+
+ if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
+ if (old) {
+ if (!submodule_uses_gitfile(path))
+ absorb_git_dir_into_superproject("", path,
+ ABSORB_GITDIR_RECURSE_SUBMODULES);
+ } else {
+ struct strbuf sb = STRBUF_INIT;
+ strbuf_addf(&sb, "%s/modules/%s",
+ get_git_common_dir(), sub->name);
+ connect_work_tree_and_git_dir(path, sb.buf);
+ strbuf_release(&sb);
+
+ /* make sure the index is clean as well */
+ submodule_reset_index(path);
+ }
+ }
+
+ prepare_submodule_repo_env_no_git_dir(&cp.env_array);
+
+ cp.git_cmd = 1;
+ cp.no_stdin = 1;
+ cp.dir = path;
+
+ argv_array_pushf(&cp.args, "--super-prefix=%s/", path);
+ argv_array_pushl(&cp.args, "read-tree", NULL);
+
+ if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
+ argv_array_push(&cp.args, "-n");
+ else
+ argv_array_push(&cp.args, "-u");
+
+ if (flags & SUBMODULE_MOVE_HEAD_FORCE)
+ argv_array_push(&cp.args, "--reset");
+ else
+ argv_array_push(&cp.args, "-m");
+
+ argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
+ argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
+
+ if (run_command(&cp)) {
+ ret = -1;
+ goto out;
+ }
+
+ if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
+ if (new) {
+ struct child_process cp1 = CHILD_PROCESS_INIT;
+ /* also set the HEAD accordingly */
+ cp1.git_cmd = 1;
+ cp1.no_stdin = 1;
+ cp1.dir = path;
+
+ argv_array_pushl(&cp1.args, "update-ref", "HEAD",
+ new ? new : EMPTY_TREE_SHA1_HEX, NULL);
+
+ if (run_command(&cp1)) {
+ ret = -1;
+ goto out;
+ }
+ } else {
+ struct strbuf sb = STRBUF_INIT;
+
+ strbuf_addf(&sb, "%s/.git", path);
+ unlink_or_warn(sb.buf);
+ strbuf_release(&sb);
+
+ if (is_empty_dir(path))
+ rmdir_or_warn(path);
+ }
+ }
+out:
+ return ret;
+}
+
static int find_first_merges(struct object_array *result, const char *path,
struct commit *a, struct commit *b)
{
diff --git a/submodule.h b/submodule.h
index 6f3fe85c7c..4cdf6445f7 100644
--- a/submodule.h
+++ b/submodule.h
@@ -96,6 +96,13 @@ extern int push_unpushed_submodules(struct sha1_array *commits,
extern void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir);
extern int parallel_submodules(void);
+#define SUBMODULE_MOVE_HEAD_DRY_RUN (1<<0)
+#define SUBMODULE_MOVE_HEAD_FORCE (1<<1)
+extern int submodule_move_head(const char *path,
+ const char *old,
+ const char *new,
+ unsigned flags);
+
/*
* Prepare the "env_array" parameter of a "struct child_process" for executing
* a submodule by clearing any repo-specific envirionment variables, but
--
2.12.0.rc1.45.g207f5fbb2b