3 files changed, 24 insertions, 0 deletions

diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index d0be879443..03e36f0183 100644
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -44,6 +44,7 @@ struct object_entry {
 				 * be used as the base objectto delta huge
 				 * objects against.
 				 */
+	uint32_t crc32;		/* crc of raw pack data for this object */
 };
 
 /*
@@ -381,6 +382,9 @@ static unsigned long write_object(struct sha1file *f,
 	enum object_type obj_type;
 	int to_reuse = 0;
 
+	if (!pack_to_stdout)
+		crc32_begin(f);
+
 	obj_type = entry->type;
 	if (! entry->in_pack)
 		to_reuse = 0;	/* can't reuse what we don't have */
@@ -496,6 +500,8 @@ static unsigned long write_object(struct sha1file *f,
 	if (entry->delta)
 		written_delta++;
 	written++;
+	if (!pack_to_stdout)
+		entry->crc32 = crc32_end(f);
 	return hdrlen + datalen;
 }
 
diff --git a/csum-file.c b/csum-file.c
index b7174c6c05..7c806ada48 100644
--- a/csum-file.c
+++ b/csum-file.c
@@ -49,6 +49,8 @@ int sha1close(struct sha1file *f, unsigned char *result, int update)
 
 int sha1write(struct sha1file *f, void *buf, unsigned int count)
 {
+	if (f->do_crc)
+		f->crc32 = crc32(f->crc32, buf, count);
 	while (count) {
 		unsigned offset = f->offset;
 		unsigned left = sizeof(f->buffer) - offset;
@@ -91,6 +93,7 @@ struct sha1file *sha1create(const char *fmt, ...)
 	f->fd = fd;
 	f->error = 0;
 	f->offset = 0;
+	f->do_crc = 0;
 	SHA1_Init(&f->ctx);
 	return f;
 }
@@ -111,6 +114,7 @@ struct sha1file *sha1fd(int fd, const char *name)
 	f->fd = fd;
 	f->error = 0;
 	f->offset = 0;
+	f->do_crc = 0;
 	SHA1_Init(&f->ctx);
 	return f;
 }
@@ -143,4 +147,14 @@ int sha1write_compressed(struct sha1file *f, void *in, unsigned int size)
 	return size;
 }
 
+void crc32_begin(struct sha1file *f)
+{
+	f->crc32 = crc32(0, Z_NULL, 0);
+	f->do_crc = 1;
+}
 
+uint32_t crc32_end(struct sha1file *f)
+{
+	f->do_crc = 0;
+	return f->crc32;
+}
diff --git a/csum-file.h b/csum-file.h
index 3ad1a992a7..7e1339189d 100644
--- a/csum-file.h
+++ b/csum-file.h
@@ -7,6 +7,8 @@ struct sha1file {
 	unsigned int offset, namelen;
 	SHA_CTX ctx;
 	char name[PATH_MAX];
+	int do_crc;
+	uint32_t crc32;
 	unsigned char buffer[8192];
 };
 
@@ -15,5 +17,7 @@ extern struct sha1file *sha1create(const char *fmt, ...) __attribute__((format (
 extern int sha1close(struct sha1file *, unsigned char *, int);
 extern int sha1write(struct sha1file *, void *, unsigned int);
 extern int sha1write_compressed(struct sha1file *, void *, unsigned int);
+extern void crc32_begin(struct sha1file *);
+extern uint32_t crc32_end(struct sha1file *);
 
 #endif