From 6e3c1595c66e2b192a2a516447c5645814766339 Mon Sep 17 00:00:00 2001 From: Stefan Beller Date: Tue, 14 Mar 2017 14:46:37 -0700 Subject: [PATCH] update submodules: add submodule_move_head 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 Signed-off-by: Junio C Hamano --- submodule.c | 137 ++++++++++++++++++++++++++++++++++++++++++++++++++++ submodule.h | 7 +++ 2 files changed, 144 insertions(+) diff --git a/submodule.c b/submodule.c index d8efbdb96e..6e8825b451 100644 --- a/submodule.c +++ b/submodule.c @@ -1247,6 +1247,143 @@ static const char *get_super_prefix_or_empty(void) return s; } +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%s/", + get_super_prefix_or_empty(), 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%s/", + get_super_prefix_or_empty(), 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 -- 2.39.2