index-pack: smarter memory usage when appending objects

In the same spirit as commit 9892bebafe, let's avoid allocating the full
buffer for the deflated data in write_compressed() in order to write it.
Let's deflate and write the data in chunks instead to reduce memory
usage.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nicolas Pitre 2010-04-12 16:50:35 -04:00 committed by Junio C Hamano
parent 7ce4721ad8
commit 7734d7f2f6

View File

@ -669,25 +669,25 @@ static void parse_pack_objects(unsigned char *sha1)
static int write_compressed(struct sha1file *f, void *in, unsigned int size)
{
z_stream stream;
unsigned long maxsize;
void *out;
int status;
unsigned char outbuf[4096];
memset(&stream, 0, sizeof(stream));
deflateInit(&stream, zlib_compression_level);
maxsize = deflateBound(&stream, size);
out = xmalloc(maxsize);
/* Compress it */
stream.next_in = in;
stream.avail_in = size;
stream.next_out = out;
stream.avail_out = maxsize;
while (deflate(&stream, Z_FINISH) == Z_OK);
deflateEnd(&stream);
do {
stream.next_out = outbuf;
stream.avail_out = sizeof(outbuf);
status = deflate(&stream, Z_FINISH);
sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
} while (status == Z_OK);
if (status != Z_STREAM_END)
die("unable to deflate appended object (%d)", status);
size = stream.total_out;
sha1write(f, out, size);
free(out);
deflateEnd(&stream);
return size;
}