commit: simplify building parents list

Push pptr down into the FROM_MERGE branch of the if/else statement,
where it's actually used, and call commit_list_append() for appending
elements instead of playing tricks with commit_list_insert().  Call
copy_commit_list() in the amend branch instead of open-coding it.  Don't
bother setting pptr in the final branch as it's not used thereafter.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/commit.c b/builtin/commit.c
index e133037..f6d6c47 100644 (file)
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1639,7 +1639,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
        const char *index_file, *reflog_msg;
        char *nl;
        unsigned char sha1[20];
-       struct commit_list *parents = NULL, **pptr = &parents;
+       struct commit_list *parents = NULL;
        struct stat statbuf;
        struct commit *current_head = NULL;
        struct commit_extra_header *extra = NULL;
@@ -1681,20 +1681,18 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                if (!reflog_msg)
                        reflog_msg = "commit (initial)";
        } else if (amend) {
-               struct commit_list *c;
-
                if (!reflog_msg)
                        reflog_msg = "commit (amend)";
-               for (c = current_head->parents; c; c = c->next)
-                       pptr = &commit_list_insert(c->item, pptr)->next;
+               parents = copy_commit_list(current_head->parents);
        } else if (whence == FROM_MERGE) {
                struct strbuf m = STRBUF_INIT;
                FILE *fp;
                int allow_fast_forward = 1;
+               struct commit_list **pptr = &parents;
 
                if (!reflog_msg)
                        reflog_msg = "commit (merge)";
-               pptr = &commit_list_insert(current_head, pptr)->next;
+               pptr = commit_list_append(current_head, pptr);
                fp = fopen(git_path_merge_head(), "r");
                if (fp == NULL)
                        die_errno(_("could not open '%s' for reading"),
@@ -1705,7 +1703,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                        parent = get_merge_parent(m.buf);
                        if (!parent)
                                die(_("Corrupt MERGE_HEAD file (%s)"), m.buf);
-                       pptr = &commit_list_insert(parent, pptr)->next;
+                       pptr = commit_list_append(parent, pptr);
                }
                fclose(fp);
                strbuf_release(&m);
@@ -1722,7 +1720,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
                        reflog_msg = (whence == FROM_CHERRY_PICK)
                                        ? "commit (cherry-pick)"
                                        : "commit";
-               pptr = &commit_list_insert(current_head, pptr)->next;
+               commit_list_insert(current_head, &parents);
        }
 
        /* Finally, get the commit message */