[PATCH v3] Replace memcpy with hashcpy when dealing hash copy globally

[Sun He <sunheehnus@gmail.com>]

Replacing memcpy with hashcpy is more directly and elegant.

Leave ppc/sha1.c alone, as it is an isolated component.
Pull cache.h(actually ../cache.h) in just for one memcpy
there is not proper.

Helped-by: Michael Haggerty <mhagger@alum.mit.edu>
Helped-by: Duy Nguyen <pclouds@gmail.com>
Signed-off-by: Sun He <sunheehnus@gmail.com>
---

PATCH v3 delete the one-space indentation on each line of commit message
as is suggested by Eric Sunshine.
 Thanks to Eric Sunshine.

PATCH v2 leave ppc/sha1.c alone.

The general rule is if cache.h or git-compat-util.h is included,
it is the first #include, and system includes will be always in
git-compat-tuil.h.
       				via Duy Nguyen

The change in PATCH v1 is not proper because I placed cache.h
in the end.
And adding it to the head is not a good way to achieve the goal,
as is said above "---".
 Thanks to Duy Nguyen.

Find the potential places with memcpy by the bash command:
 $ find . | xargs grep "memcpy.*\(.*20.*\)"

ppc/sha1.c doesn't include cache.h and it cannot use hashcpy().
So just leave memcpy(in ppc/sha1.c) alone.

 bundle.c            | 2 +-
 grep.c              | 2 +-
 pack-bitmap-write.c | 2 +-
 reflog-walk.c       | 4 ++--
 refs.c              | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/bundle.c b/bundle.c
index e99065c..7809fbb 100644
--- a/bundle.c
+++ b/bundle.c
@@ -19,7 +19,7 @@ static void add_to_ref_list(const unsigned char *sha1, const char *name,
 		list->list = xrealloc(list->list,
 				list->alloc * sizeof(list->list[0]));
 	}
-	memcpy(list->list[list->nr].sha1, sha1, 20);
+	hashcpy(list->list[list->nr].sha1, sha1);
 	list->list[list->nr].name = xstrdup(name);
 	list->nr++;
 }
diff --git a/grep.c b/grep.c
index c668034..f5101f7 100644
--- a/grep.c
+++ b/grep.c
@@ -1650,7 +1650,7 @@ void grep_source_init(struct grep_source *gs, enum grep_source_type type,
 		break;
 	case GREP_SOURCE_SHA1:
 		gs->identifier = xmalloc(20);
-		memcpy(gs->identifier, identifier, 20);
+		hashcpy(gs->identifier, identifier);
 		break;
 	case GREP_SOURCE_BUF:
 		gs->identifier = NULL;
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c
index 1218bef..5f1791a 100644
--- a/pack-bitmap-write.c
+++ b/pack-bitmap-write.c
@@ -530,7 +530,7 @@ void bitmap_writer_finish(struct pack_idx_entry **index,
 	header.version = htons(default_version);
 	header.options = htons(flags | options);
 	header.entry_count = htonl(writer.selected_nr);
-	memcpy(header.checksum, writer.pack_checksum, 20);
+	hashcpy(header.checksum, writer.pack_checksum);
 
 	sha1write(f, &header, sizeof(header));
 	dump_bitmap(f, writer.commits);
diff --git a/reflog-walk.c b/reflog-walk.c
index b2fbdb2..d490f7d 100644
--- a/reflog-walk.c
+++ b/reflog-walk.c
@@ -32,8 +32,8 @@ static int read_one_reflog(unsigned char *osha1, unsigned char *nsha1,
 			sizeof(struct reflog_info));
 	}
 	item = array->items + array->nr;
-	memcpy(item->osha1, osha1, 20);
-	memcpy(item->nsha1, nsha1, 20);
+	hashcpy(item->osha1, osha1);
+	hashcpy(item->nsha1, nsha1);
 	item->email = xstrdup(email);
 	item->timestamp = timestamp;
 	item->tz = tz;
diff --git a/refs.c b/refs.c
index 89228e2..f90b7ea 100644
--- a/refs.c
+++ b/refs.c
@@ -1222,7 +1222,7 @@ static int resolve_gitlink_packed_ref(struct ref_cache *refs,
 	if (ref == NULL)
 		return -1;
 
-	memcpy(sha1, ref->u.value.sha1, 20);
+	hashcpy(sha1, ref->u.value.sha1);
 	return 0;
 }
 
-- 
1.9.0.138.g2de3478.dirty