[PATCH v4 4/9] commit: move post-rewrite code to libgit

[Phillip Wood]

From: Phillip Wood <phillip.w...@dunelm.org.uk>

Move run_rewrite_hook() from bulitin/commit.c to sequencer.c so it can
be shared with other commands and add a new function
commit_post_rewrite() based on the code in builtin/commit.c that
encapsulates rewriting notes and running the post-rewrite hook. Once
the sequencer learns how to create commits without forking 'git
commit' these functions will be used when squashing commits.

Signed-off-by: Phillip Wood <phillip.w...@dunelm.org.uk>
---

Notes:
    changes since v1:
     - reword commit message to explain why the code is being moved

 builtin/commit.c | 42 +-----------------------------------------
 sequencer.c      | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 sequencer.h      |  2 ++
 3 files changed, 50 insertions(+), 41 deletions(-)

diff --git a/builtin/commit.c b/builtin/commit.c
index 
eb144556bf37b7bf357bd976b94305171b4fd159..d251cfcebad3476c365492d83803e7821fdfdf2b
 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -31,9 +31,7 @@
 #include "gpg-interface.h"
 #include "column.h"
 #include "sequencer.h"
-#include "notes-utils.h"
 #include "mailmap.h"
-#include "sigchain.h"
 
 static const char * const builtin_commit_usage[] = {
        N_("git commit [<options>] [--] <pathspec>..."),
@@ -1497,37 +1495,6 @@ static int git_commit_config(const char *k, const char 
*v, void *cb)
        return git_status_config(k, v, s);
 }
 
-static int run_rewrite_hook(const struct object_id *oldoid,
-                           const struct object_id *newoid)
-{
-       struct child_process proc = CHILD_PROCESS_INIT;
-       const char *argv[3];
-       int code;
-       struct strbuf sb = STRBUF_INIT;
-
-       argv[0] = find_hook("post-rewrite");
-       if (!argv[0])
-               return 0;
-
-       argv[1] = "amend";
-       argv[2] = NULL;
-
-       proc.argv = argv;
-       proc.in = -1;
-       proc.stdout_to_stderr = 1;
-
-       code = start_command(&proc);
-       if (code)
-               return code;
-       strbuf_addf(&sb, "%s %s\n", oid_to_hex(oldoid), oid_to_hex(newoid));
-       sigchain_push(SIGPIPE, SIG_IGN);
-       write_in_full(proc.in, sb.buf, sb.len);
-       close(proc.in);
-       strbuf_release(&sb);
-       sigchain_pop(SIGPIPE);
-       return finish_command(&proc);
-}
-
 int run_commit_hook(int editor_is_used, const char *index_file, const char 
*name, ...)
 {
        struct argv_array hook_env = ARGV_ARRAY_INIT;
@@ -1758,14 +1725,7 @@ int cmd_commit(int argc, const char **argv, const char 
*prefix)
        rerere(0);
        run_commit_hook(use_editor, get_index_file(), "post-commit", NULL);
        if (amend && !no_post_rewrite) {
-               struct notes_rewrite_cfg *cfg;
-               cfg = init_copy_notes_for_rewrite("amend");
-               if (cfg) {
-                       /* we are amending, so current_head is not NULL */
-                       copy_note_for_rewrite(cfg, &current_head->object.oid, 
&oid);
-                       finish_copy_notes_for_rewrite(cfg, "Notes added by 'git 
commit --amend'");
-               }
-               run_rewrite_hook(&current_head->object.oid, &oid);
+               commit_post_rewrite(current_head, &oid);
        }
        if (!quiet)
                print_summary(prefix, &oid, !current_head);
diff --git a/sequencer.c b/sequencer.c
index 
ef262980c5255d90ee023c0b29c6c1c628b3c7d2..6bc8346d42bb3cb1d2dc6a2238dd1b38e4308914
 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -21,6 +21,8 @@
 #include "log-tree.h"
 #include "wt-status.h"
 #include "hashmap.h"
+#include "notes-utils.h"
+#include "sigchain.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
@@ -789,6 +791,51 @@ int update_head_with_reflog(const struct commit *old_head,
        return ret;
 }
 
+static int run_rewrite_hook(const struct object_id *oldoid,
+                           const struct object_id *newoid)
+{
+       struct child_process proc = CHILD_PROCESS_INIT;
+       const char *argv[3];
+       int code;
+       struct strbuf sb = STRBUF_INIT;
+
+       argv[0] = find_hook("post-rewrite");
+       if (!argv[0])
+               return 0;
+
+       argv[1] = "amend";
+       argv[2] = NULL;
+
+       proc.argv = argv;
+       proc.in = -1;
+       proc.stdout_to_stderr = 1;
+
+       code = start_command(&proc);
+       if (code)
+               return code;
+       strbuf_addf(&sb, "%s %s\n", oid_to_hex(oldoid), oid_to_hex(newoid));
+       sigchain_push(SIGPIPE, SIG_IGN);
+       write_in_full(proc.in, sb.buf, sb.len);
+       close(proc.in);
+       strbuf_release(&sb);
+       sigchain_pop(SIGPIPE);
+       return finish_command(&proc);
+}
+
+void commit_post_rewrite(const struct commit *old_head,
+                        const struct object_id *new_head)
+{
+       struct notes_rewrite_cfg *cfg;
+
+       cfg = init_copy_notes_for_rewrite("amend");
+       if (cfg) {
+               /* we are amending, so old_head is not NULL */
+               copy_note_for_rewrite(cfg, &old_head->object.oid, new_head);
+               finish_copy_notes_for_rewrite(cfg, "Notes added by 'git commit 
--amend'");
+       }
+       run_rewrite_hook(&old_head->object.oid, new_head);
+}
+
 static int is_original_commit_empty(struct commit *commit)
 {
        const struct object_id *ptree_oid;
diff --git a/sequencer.h b/sequencer.h
index 
81a2098e900f0aca30e45ed7f19ae4bf3ce682f0..ec13b679c40dc4012a84a761ea856d6e75953490
 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -73,4 +73,6 @@ int update_head_with_reflog(const struct commit *old_head,
                            const struct object_id *new_head,
                            const char *action, const struct strbuf *msg,
                            struct strbuf *err);
+void commit_post_rewrite(const struct commit *current_head,
+                        const struct object_id *new_head);
 #endif
-- 
2.15.0