git/pack-write.c
Dana L. How 8b0eca7c7b Create pack-write.c for common pack writing code
Include a generalized fixup_pack_header_footer() in this new file.
Needed by git-repack --max-pack-size feature in a later patchset.

[sp: Moved close(pack_fd) to callers, to support index-pack, and
     changed name to better indicate it is for packfiles.]

Signed-off-by: Dana L. How <danahow@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2007-05-02 13:24:18 -04:00

40 lines
1,019 B
C

#include "cache.h"
#include "pack.h"
void fixup_pack_header_footer(int pack_fd,
unsigned char *pack_file_sha1,
const char *pack_name,
uint32_t object_count)
{
static const int buf_sz = 128 * 1024;
SHA_CTX c;
struct pack_header hdr;
char *buf;
if (lseek(pack_fd, 0, SEEK_SET) != 0)
die("Failed seeking to start: %s", strerror(errno));
if (read_in_full(pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
die("Unable to reread header of %s: %s", pack_name, strerror(errno));
if (lseek(pack_fd, 0, SEEK_SET) != 0)
die("Failed seeking to start: %s", strerror(errno));
hdr.hdr_entries = htonl(object_count);
write_or_die(pack_fd, &hdr, sizeof(hdr));
SHA1_Init(&c);
SHA1_Update(&c, &hdr, sizeof(hdr));
buf = xmalloc(buf_sz);
for (;;) {
size_t n = xread(pack_fd, buf, buf_sz);
if (!n)
break;
if (n < 0)
die("Failed to checksum %s: %s", pack_name, strerror(errno));
SHA1_Update(&c, buf, n);
}
free(buf);
SHA1_Final(pack_file_sha1, &c);
write_or_die(pack_fd, pack_file_sha1, 20);
}