#include "pack-revindex.h"
#include "object-store.h"
#include "packfile.h"
+#include "config.h"
struct revindex_entry {
off_t offset;
sort_revindex(p->revindex, num_ent, p->pack_size);
}
-int load_pack_revindex(struct packed_git *p)
+static int create_pack_revindex_in_memory(struct packed_git *p)
{
- if (!p->revindex) {
- if (open_pack_index(p))
- return -1;
- create_pack_revindex(p);
- }
+ if (git_env_bool(GIT_TEST_REV_INDEX_DIE_IN_MEMORY, 0))
+ die("dying as requested by '%s'",
+ GIT_TEST_REV_INDEX_DIE_IN_MEMORY);
+ if (open_pack_index(p))
+ return -1;
+ create_pack_revindex(p);
return 0;
}
+static char *pack_revindex_filename(struct packed_git *p)
+{
+ size_t len;
+ if (!strip_suffix(p->pack_name, ".pack", &len))
+ BUG("pack_name does not end in .pack");
+ return xstrfmt("%.*s.rev", (int)len, p->pack_name);
+}
+
+#define RIDX_HEADER_SIZE (12)
+#define RIDX_MIN_SIZE (RIDX_HEADER_SIZE + (2 * the_hash_algo->rawsz))
+
+struct revindex_header {
+ uint32_t signature;
+ uint32_t version;
+ uint32_t hash_id;
+};
+
+static int load_revindex_from_disk(char *revindex_name,
+ uint32_t num_objects,
+ const uint32_t **data_p, size_t *len_p)
+{
+ int fd, ret = 0;
+ struct stat st;
+ void *data = NULL;
+ size_t revindex_size;
+ struct revindex_header *hdr;
+
+ fd = git_open(revindex_name);
+
+ if (fd < 0) {
+ ret = -1;
+ goto cleanup;
+ }
+ if (fstat(fd, &st)) {
+ ret = error_errno(_("failed to read %s"), revindex_name);
+ goto cleanup;
+ }
+
+ revindex_size = xsize_t(st.st_size);
+
+ if (revindex_size < RIDX_MIN_SIZE) {
+ ret = error(_("reverse-index file %s is too small"), revindex_name);
+ goto cleanup;
+ }
+
+ if (revindex_size - RIDX_MIN_SIZE != st_mult(sizeof(uint32_t), num_objects)) {
+ ret = error(_("reverse-index file %s is corrupt"), revindex_name);
+ goto cleanup;
+ }
+
+ data = xmmap(NULL, revindex_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ hdr = data;
+
+ if (ntohl(hdr->signature) != RIDX_SIGNATURE) {
+ ret = error(_("reverse-index file %s has unknown signature"), revindex_name);
+ goto cleanup;
+ }
+ if (ntohl(hdr->version) != 1) {
+ ret = error(_("reverse-index file %s has unsupported version %"PRIu32),
+ revindex_name, ntohl(hdr->version));
+ goto cleanup;
+ }
+ if (!(ntohl(hdr->hash_id) == 1 || ntohl(hdr->hash_id) == 2)) {
+ ret = error(_("reverse-index file %s has unsupported hash id %"PRIu32),
+ revindex_name, ntohl(hdr->hash_id));
+ goto cleanup;
+ }
+
+cleanup:
+ if (ret) {
+ if (data)
+ munmap(data, revindex_size);
+ } else {
+ *len_p = revindex_size;
+ *data_p = (const uint32_t *)data;
+ }
+
+ close(fd);
+ return ret;
+}
+
+static int load_pack_revindex_from_disk(struct packed_git *p)
+{
+ char *revindex_name;
+ int ret;
+ if (open_pack_index(p))
+ return -1;
+
+ revindex_name = pack_revindex_filename(p);
+
+ ret = load_revindex_from_disk(revindex_name,
+ p->num_objects,
+ &p->revindex_map,
+ &p->revindex_size);
+ if (ret)
+ goto cleanup;
+
+ p->revindex_data = (const uint32_t *)((const char *)p->revindex_map + RIDX_HEADER_SIZE);
+
+cleanup:
+ free(revindex_name);
+ return ret;
+}
+
+int load_pack_revindex(struct packed_git *p)
+{
+ if (p->revindex || p->revindex_data)
+ return 0;
+
+ if (!load_pack_revindex_from_disk(p))
+ return 0;
+ else if (!create_pack_revindex_in_memory(p))
+ return 0;
+ return -1;
+}
+
int offset_to_pack_pos(struct packed_git *p, off_t ofs, uint32_t *pos)
{
unsigned lo, hi;
- const struct revindex_entry *revindex;
if (load_pack_revindex(p) < 0)
return -1;
lo = 0;
hi = p->num_objects + 1;
- revindex = p->revindex;
do {
const unsigned mi = lo + (hi - lo) / 2;
- if (revindex[mi].offset == ofs) {
+ off_t got = pack_pos_to_offset(p, mi);
+
+ if (got == ofs) {
*pos = mi;
return 0;
- } else if (ofs < revindex[mi].offset)
+ } else if (ofs < got)
hi = mi;
else
lo = mi + 1;
uint32_t pack_pos_to_index(struct packed_git *p, uint32_t pos)
{
- if (!p->revindex)
+ if (!(p->revindex || p->revindex_data))
BUG("pack_pos_to_index: reverse index not yet loaded");
if (p->num_objects <= pos)
BUG("pack_pos_to_index: out-of-bounds object at %"PRIu32, pos);
- return p->revindex[pos].nr;
+
+ if (p->revindex)
+ return p->revindex[pos].nr;
+ else
+ return get_be32(p->revindex_data + pos);
}
off_t pack_pos_to_offset(struct packed_git *p, uint32_t pos)
{
- if (!p->revindex)
+ if (!(p->revindex || p->revindex_data))
BUG("pack_pos_to_index: reverse index not yet loaded");
if (p->num_objects < pos)
BUG("pack_pos_to_offset: out-of-bounds object at %"PRIu32, pos);
- return p->revindex[pos].offset;
+
+ if (p->revindex)
+ return p->revindex[pos].offset;
+ else if (pos == p->num_objects)
+ return p->pack_size - the_hash_algo->rawsz;
+ else
+ return nth_packed_object_offset(p, pack_pos_to_index(p, pos));
}
projects / thirdparty / git.git / blobdiff