Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
midx.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++--
midx.h | 2 ++
object-store.h | 1 +
packfile.c | 8 ++++-
4 files changed, 104 insertions(+), 3 deletions(-)
diff --git a/midx.c b/midx.c
index 5e9290ca8f..6eca8f1b12 100644
--- a/midx.c
+++ b/midx.c
@@ -3,6 +3,7 @@
#include "dir.h"
#include "csum-file.h"
#include "lockfile.h"
+#include "sha1-lookup.h"
#include "object-store.h"
#include "packfile.h"
#include "midx.h"
@@ -64,7 +65,7 @@ struct midxed_git *load_midxed_git(const char *object_dir)
m = xcalloc(1, sizeof(*m) + strlen(object_dir) + 1);
strcpy(m->object_dir, object_dir);
- m->data = midx_map;
+ m->data = (const unsigned char*)midx_map;
m->signature = get_be32(m->data);
if (m->signature != MIDX_SIGNATURE) {
@@ -145,7 +146,9 @@ struct midxed_git *load_midxed_git(const char *object_dir)
m->num_objects = ntohl(m->chunk_oid_fanout[255]);
- m->pack_names = xcalloc(m->num_packs, sizeof(const char *));
+ m->packs = xcalloc(m->num_packs, sizeof(*m->packs));
+
+ ALLOC_ARRAY(m->pack_names, m->num_packs);
for (i = 0; i < m->num_packs; i++) {
if (i) {
if (ntohl(m->chunk_pack_lookup[i]) <=
ntohl(m->chunk_pack_lookup[i - 1])) {
@@ -175,6 +178,95 @@ struct midxed_git *load_midxed_git(const char *object_dir)
exit(1);
}
+static int prepare_midx_pack(struct midxed_git *m, uint32_t pack_int_id)
+{
+ struct strbuf pack_name = STRBUF_INIT;
+
+ if (pack_int_id >= m->num_packs)
+ BUG("bad pack-int-id");
+
+ if (m->packs[pack_int_id])
+ return 0;
+
+ strbuf_addstr(&pack_name, m->object_dir);
+ strbuf_addstr(&pack_name, "/pack/");
+ strbuf_addstr(&pack_name, m->pack_names[pack_int_id]);
+
+ m->packs[pack_int_id] = add_packed_git(pack_name.buf, pack_name.len, 1);
+ strbuf_release(&pack_name);
+ return !m->packs[pack_int_id];
+}
+
+int bsearch_midx(const struct object_id *oid, struct midxed_git *m, uint32_t
*result)
+{
+ return bsearch_hash(oid->hash, m->chunk_oid_fanout, m->chunk_oid_lookup,
+ MIDX_HASH_LEN, result);
+}
+
+static off_t nth_midxed_offset(struct midxed_git *m, uint32_t pos)
+{
+ const unsigned char *offset_data;
+ uint32_t offset32;
+
+ offset_data = m->chunk_object_offsets + pos * MIDX_CHUNK_OFFSET_WIDTH;
+ offset32 = get_be32(offset_data + sizeof(uint32_t));
+
+ if (m->chunk_large_offsets && offset32 & MIDX_LARGE_OFFSET_NEEDED) {
+ if (sizeof(offset32) < sizeof(uint64_t))
+ die(_("multi-pack-index stores a 64-bit offset, but
off_t is too small"));
+
+ offset32 ^= MIDX_LARGE_OFFSET_NEEDED;
+ return get_be64(m->chunk_large_offsets + sizeof(uint64_t) *
offset32);
+ }
+
+ return offset32;
+}
+
+static uint32_t nth_midxed_pack_int_id(struct midxed_git *m, uint32_t pos)
+{
+ return get_be32(m->chunk_object_offsets + pos *
MIDX_CHUNK_OFFSET_WIDTH);
+}
+
+static int nth_midxed_pack_entry(struct midxed_git *m, struct pack_entry *e,
uint32_t pos)
+{
+ uint32_t pack_int_id;
+ struct packed_git *p;
+
+ if (pos >= m->num_objects)
+ return 0;
+
+ pack_int_id = nth_midxed_pack_int_id(m, pos);
+
+ if (prepare_midx_pack(m, pack_int_id))
+ die(_("error preparing packfile from multi-pack-index"));
+ p = m->packs[pack_int_id];
+
+ /*
+ * We are about to tell the caller where they can locate the
+ * requested object. We better make sure the packfile is
+ * still here and can be accessed before supplying that
+ * answer, as it may have been deleted since the MIDX was
+ * loaded!
+ */
+ if (!is_pack_valid(p))
+ return 0;
+
+ e->offset = nth_midxed_offset(m, pos);
+ e->p = p;
+
+ return 1;
+}
+
+int fill_midx_entry(const struct object_id *oid, struct pack_entry *e, struct
midxed_git *m)
+{
+ uint32_t pos;
+
+ if (!bsearch_midx(oid, m, &pos))
+ return 0;
+
+ return nth_midxed_pack_entry(m, e, pos);
+}
+
int prepare_midxed_git_one(struct repository *r, const char *object_dir)
{
struct midxed_git *m = r->objects->midxed_git;
diff --git a/midx.h b/midx.h
index 793203fc4a..0c66812229 100644
--- a/midx.h
+++ b/midx.h
@@ -8,6 +8,8 @@
#include "repository.h"
struct midxed_git *load_midxed_git(const char *object_dir);
+int bsearch_midx(const struct object_id *oid, struct midxed_git *m, uint32_t
*result);
+int fill_midx_entry(const struct object_id *oid, struct pack_entry *e, struct
midxed_git *m);
int prepare_midxed_git_one(struct repository *r, const char *object_dir);
int write_midx_file(const char *object_dir);
diff --git a/object-store.h b/object-store.h
index 7908d46e34..5af2a852bc 100644
--- a/object-store.h
+++ b/object-store.h
@@ -108,6 +108,7 @@ struct midxed_git {
const unsigned char *chunk_large_offsets;
const char **pack_names;
+ struct packed_git **packs;
char object_dir[FLEX_ARRAY];
};
diff --git a/packfile.c b/packfile.c
index b91ca9b9f5..73f8cc28ee 100644
--- a/packfile.c
+++ b/packfile.c
@@ -1857,11 +1857,17 @@ static int fill_pack_entry(const struct object_id *oid,
int find_pack_entry(struct repository *r, const struct object_id *oid, struct
pack_entry *e)
{
struct list_head *pos;
+ struct midxed_git *m;
prepare_packed_git(r);
- if (!r->objects->packed_git)
+ if (!r->objects->packed_git && !r->objects->midxed_git)
return 0;
+ for (m = r->objects->midxed_git; m; m = m->next) {
+ if (fill_midx_entry(oid, e, m))
+ return 1;
+ }
+
list_for_each(pos, &r->objects->packed_git_mru) {
struct packed_git *p = list_entry(pos, struct packed_git, mru);
if (fill_pack_entry(oid, e, p)) {
--
2.18.0.rc1
