[PATCH 2/3] pack-write: split up finish_tmp_packfile() function

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Split up the finish_tmp_packfile() function and use the split-up
version in pack-objects.c. This change should not change any
functionality, but sets up code flow for a bug fix where we'll be able
to move the *.idx in-place after the *.bitmap is written.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 builtin/pack-objects.c |  9 ++++++---
 pack-write.c           | 39 +++++++++++++++++++++++++++++++--------
 pack.h                 |  9 +++++++++
 3 files changed, 46 insertions(+), 11 deletions(-)

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 717003563db..9fa4c6a9be8 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -1217,6 +1217,7 @@ static void write_pack_file(void)
 		if (!pack_to_stdout) {
 			struct stat st;
 			struct strbuf tmp_basename = STRBUF_INIT;
+			char *idx_tmp_name = NULL;
 
 			/*
 			 * Packs are runtime accessed in their mtime
@@ -1245,9 +1246,10 @@ static void write_pack_file(void)
 					&to_pack, written_list, nr_written);
 			}
 
-			finish_tmp_packfile(&tmp_basename, pack_tmp_name,
-					    written_list, nr_written,
-					    &pack_idx_opts, hash);
+			stage_tmp_packfile(&tmp_basename, pack_tmp_name,
+					   written_list, nr_written,
+					   &pack_idx_opts, hash, &idx_tmp_name);
+			rename_tmp_packfile_idx(&tmp_basename, hash, &idx_tmp_name);
 
 			if (write_bitmap_index) {
 				struct strbuf sb = STRBUF_INIT;
@@ -1267,6 +1269,7 @@ static void write_pack_file(void)
 				strbuf_release(&sb);
 			}
 
+			free(idx_tmp_name);
 			strbuf_release(&tmp_basename);
 			free(pack_tmp_name);
 			puts(hash_to_hex(hash));
diff --git a/pack-write.c b/pack-write.c
index 57b9fc11423..ba5c4767dc8 100644
--- a/pack-write.c
+++ b/pack-write.c
@@ -468,16 +468,33 @@ void finish_tmp_packfile(const struct strbuf *tmp_basename,
 			 uint32_t nr_written,
 			 struct pack_idx_option *pack_idx_opts,
 			 unsigned char hash[])
+{
+	char *idx_tmp_name = NULL;
+
+	stage_tmp_packfile(tmp_basename, pack_tmp_name, written_list,
+			   nr_written, pack_idx_opts, hash, &idx_tmp_name);
+	rename_tmp_packfile_idx(tmp_basename, hash, &idx_tmp_name);
+
+	free(idx_tmp_name);
+}
+
+void stage_tmp_packfile(const struct strbuf *tmp_basename,
+			const char *pack_tmp_name,
+			struct pack_idx_entry **written_list,
+			uint32_t nr_written,
+			struct pack_idx_option *pack_idx_opts,
+			unsigned char hash[],
+			char **idx_tmp_name)
 {
 	struct strbuf sb = STRBUF_INIT;
-	const char *idx_tmp_name, *rev_tmp_name = NULL;
+	const char *rev_tmp_name = NULL;
 
 	if (adjust_shared_perm(pack_tmp_name))
 		die_errno("unable to make temporary pack file readable");
 
-	idx_tmp_name = write_idx_file(NULL, written_list, nr_written,
-				      pack_idx_opts, hash);
-	if (adjust_shared_perm(idx_tmp_name))
+	*idx_tmp_name = (char *)write_idx_file(NULL, written_list, nr_written,
+					       pack_idx_opts, hash);
+	if (adjust_shared_perm(*idx_tmp_name))
 		die_errno("unable to make temporary index file readable");
 
 	rev_tmp_name = write_rev_file(NULL, written_list, nr_written, hash,
@@ -496,12 +513,18 @@ void finish_tmp_packfile(const struct strbuf *tmp_basename,
 		strbuf_reset(&sb);
 	}
 
+	strbuf_release(&sb);
+}
+
+void rename_tmp_packfile_idx(const struct strbuf *tmp_basename,
+			     unsigned char hash[], char **idx_tmp_name)
+{
+	struct strbuf sb = STRBUF_INIT;
+
 	strbuf_addf(&sb, "%s%s.idx", tmp_basename->buf, hash_to_hex(hash));
-	if (rename(idx_tmp_name, sb.buf))
+	if (rename(*idx_tmp_name, sb.buf))
 		die_errno("unable to rename temporary index file");
-	strbuf_reset(&sb);
-
-	free((void *)idx_tmp_name);
+	strbuf_release(&sb);
 }
 
 void write_promisor_file(const char *promisor_name, struct ref **sought, int nr_sought)
diff --git a/pack.h b/pack.h
index ae0c9e04cd9..6c1508c3de7 100644
--- a/pack.h
+++ b/pack.h
@@ -110,6 +110,15 @@ int encode_in_pack_object_header(unsigned char *hdr, int hdr_len,
 int read_pack_header(int fd, struct pack_header *);
 
 struct hashfile *create_tmp_packfile(char **pack_tmp_name);
+void stage_tmp_packfile(const struct strbuf *tmp_basename,
+			const char *pack_tmp_name,
+			struct pack_idx_entry **written_list,
+			uint32_t nr_written,
+			struct pack_idx_option *pack_idx_opts,
+			unsigned char hash[],
+			char **idx_tmp_name);
+void rename_tmp_packfile_idx(const struct strbuf *tmp_basename,
+			     unsigned char hash[], char **idx_tmp_name);
 void finish_tmp_packfile(const struct strbuf *name_buffer,
 			 const char *pack_tmp_name,
 			 struct pack_idx_entry **written_list,
-- 
2.33.0.818.gd2ef2916285