--- /dev/null
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "midx.h"
+
+#include "array.h"
+#include "buf.h"
+#include "filebuf.h"
+#include "futils.h"
+#include "hash.h"
+#include "odb.h"
+#include "pack.h"
+#include "fs_path.h"
+#include "repository.h"
+#include "str.h"
+
+#define MIDX_SIGNATURE 0x4d494458 /* "MIDX" */
+#define MIDX_VERSION 1
+#define MIDX_OBJECT_ID_VERSION 1
+struct git_midx_header {
+ uint32_t signature;
+ uint8_t version;
+ uint8_t object_id_version;
+ uint8_t chunks;
+ uint8_t base_midx_files;
+ uint32_t packfiles;
+};
+
+#define MIDX_PACKFILE_NAMES_ID 0x504e414d /* "PNAM" */
+#define MIDX_OID_FANOUT_ID 0x4f494446 /* "OIDF" */
+#define MIDX_OID_LOOKUP_ID 0x4f49444c /* "OIDL" */
+#define MIDX_OBJECT_OFFSETS_ID 0x4f4f4646 /* "OOFF" */
+#define MIDX_OBJECT_LARGE_OFFSETS_ID 0x4c4f4646 /* "LOFF" */
+
+struct git_midx_chunk {
+ off64_t offset;
+ size_t length;
+};
+
+typedef int (*midx_write_cb)(const char *buf, size_t size, void *cb_data);
+
+static int midx_error(const char *message)
+{
+ git_error_set(GIT_ERROR_ODB, "invalid multi-pack-index file - %s", message);
+ return -1;
+}
+
+static int midx_parse_packfile_names(
+ git_midx_file *idx,
+ const unsigned char *data,
+ uint32_t packfiles,
+ struct git_midx_chunk *chunk)
+{
+ int error;
+ uint32_t i;
+ char *packfile_name = (char *)(data + chunk->offset);
+ size_t chunk_size = chunk->length, len;
+ if (chunk->offset == 0)
+ return midx_error("missing Packfile Names chunk");
+ if (chunk->length == 0)
+ return midx_error("empty Packfile Names chunk");
+ if ((error = git_vector_init(&idx->packfile_names, packfiles, git__strcmp_cb)) < 0)
+ return error;
+ for (i = 0; i < packfiles; ++i) {
+ len = p_strnlen(packfile_name, chunk_size);
+ if (len == 0)
+ return midx_error("empty packfile name");
+ if (len + 1 > chunk_size)
+ return midx_error("unterminated packfile name");
+ git_vector_insert(&idx->packfile_names, packfile_name);
+ if (i && strcmp(git_vector_get(&idx->packfile_names, i - 1), packfile_name) >= 0)
+ return midx_error("packfile names are not sorted");
+ if (strlen(packfile_name) <= strlen(".idx") || git__suffixcmp(packfile_name, ".idx") != 0)
+ return midx_error("non-.idx packfile name");
+ if (strchr(packfile_name, '/') != NULL || strchr(packfile_name, '\\') != NULL)
+ return midx_error("non-local packfile");
+ packfile_name += len + 1;
+ chunk_size -= len + 1;
+ }
+ return 0;
+}
+
+static int midx_parse_oid_fanout(
+ git_midx_file *idx,
+ const unsigned char *data,
+ struct git_midx_chunk *chunk_oid_fanout)
+{
+ uint32_t i, nr;
+ if (chunk_oid_fanout->offset == 0)
+ return midx_error("missing OID Fanout chunk");
+ if (chunk_oid_fanout->length == 0)
+ return midx_error("empty OID Fanout chunk");
+ if (chunk_oid_fanout->length != 256 * 4)
+ return midx_error("OID Fanout chunk has wrong length");
+
+ idx->oid_fanout = (const uint32_t *)(data + chunk_oid_fanout->offset);
+ nr = 0;
+ for (i = 0; i < 256; ++i) {
+ uint32_t n = ntohl(idx->oid_fanout[i]);
+ if (n < nr)
+ return midx_error("index is non-monotonic");
+ nr = n;
+ }
+ idx->num_objects = nr;
+ return 0;
+}
+
+static int midx_parse_oid_lookup(
+ git_midx_file *idx,
+ const unsigned char *data,
+ struct git_midx_chunk *chunk_oid_lookup)
+{
+ uint32_t i;
+ unsigned char *oid, *prev_oid, zero_oid[GIT_OID_RAWSZ] = {0};
+
+ if (chunk_oid_lookup->offset == 0)
+ return midx_error("missing OID Lookup chunk");
+ if (chunk_oid_lookup->length == 0)
+ return midx_error("empty OID Lookup chunk");
+ if (chunk_oid_lookup->length != idx->num_objects * GIT_OID_RAWSZ)
+ return midx_error("OID Lookup chunk has wrong length");
+
+ idx->oid_lookup = oid = (unsigned char *)(data + chunk_oid_lookup->offset);
+ prev_oid = zero_oid;
+ for (i = 0; i < idx->num_objects; ++i, oid += GIT_OID_RAWSZ) {
+ if (git_oid_raw_cmp(prev_oid, oid) >= 0)
+ return midx_error("OID Lookup index is non-monotonic");
+ prev_oid = oid;
+ }
+
+ return 0;
+}
+
+static int midx_parse_object_offsets(
+ git_midx_file *idx,
+ const unsigned char *data,
+ struct git_midx_chunk *chunk_object_offsets)
+{
+ if (chunk_object_offsets->offset == 0)
+ return midx_error("missing Object Offsets chunk");
+ if (chunk_object_offsets->length == 0)
+ return midx_error("empty Object Offsets chunk");
+ if (chunk_object_offsets->length != idx->num_objects * 8)
+ return midx_error("Object Offsets chunk has wrong length");
+
+ idx->object_offsets = data + chunk_object_offsets->offset;
+
+ return 0;
+}
+
+static int midx_parse_object_large_offsets(
+ git_midx_file *idx,
+ const unsigned char *data,
+ struct git_midx_chunk *chunk_object_large_offsets)
+{
+ if (chunk_object_large_offsets->length == 0)
+ return 0;
+ if (chunk_object_large_offsets->length % 8 != 0)
+ return midx_error("malformed Object Large Offsets chunk");
+
+ idx->object_large_offsets = data + chunk_object_large_offsets->offset;
+ idx->num_object_large_offsets = chunk_object_large_offsets->length / 8;
+
+ return 0;
+}
+
+int git_midx_parse(
+ git_midx_file *idx,
+ const unsigned char *data,
+ size_t size)
+{
+ struct git_midx_header *hdr;
+ const unsigned char *chunk_hdr;
+ struct git_midx_chunk *last_chunk;
+ uint32_t i;
+ off64_t last_chunk_offset, chunk_offset, trailer_offset;
+ size_t checksum_size;
+ int error;
+ struct git_midx_chunk chunk_packfile_names = {0},
+ chunk_oid_fanout = {0},
+ chunk_oid_lookup = {0},
+ chunk_object_offsets = {0},
+ chunk_object_large_offsets = {0};
+
+ GIT_ASSERT_ARG(idx);
+
+ if (size < sizeof(struct git_midx_header) + GIT_OID_RAWSZ)
+ return midx_error("multi-pack index is too short");
+
+ hdr = ((struct git_midx_header *)data);
+
+ if (hdr->signature != htonl(MIDX_SIGNATURE) ||
+ hdr->version != MIDX_VERSION ||
+ hdr->object_id_version != MIDX_OBJECT_ID_VERSION) {
+ return midx_error("unsupported multi-pack index version");
+ }
+ if (hdr->chunks == 0)
+ return midx_error("no chunks in multi-pack index");
+
+ /*
+ * The very first chunk's offset should be after the header, all the chunk
+ * headers, and a special zero chunk.
+ */
+ last_chunk_offset =
+ sizeof(struct git_midx_header) +
+ (1 + hdr->chunks) * 12;
+
+ checksum_size = GIT_HASH_SHA1_SIZE;
+ trailer_offset = size - checksum_size;
+
+ if (trailer_offset < last_chunk_offset)
+ return midx_error("wrong index size");
+ memcpy(idx->checksum, data + trailer_offset, checksum_size);
+
+ chunk_hdr = data + sizeof(struct git_midx_header);
+ last_chunk = NULL;
+ for (i = 0; i < hdr->chunks; ++i, chunk_hdr += 12) {
+ uint32_t chunk_id = ntohl(*((uint32_t *)(chunk_hdr + 0)));
+ uint64_t high_offset = ((uint64_t)ntohl(*((uint32_t *)(chunk_hdr + 4)))) & 0xffffffffu;
+ uint64_t low_offset = ((uint64_t)ntohl(*((uint32_t *)(chunk_hdr + 8)))) & 0xffffffffu;
+
+ if (high_offset >= INT32_MAX)
+ return midx_error("chunk offset out of range");
+ chunk_offset = (off64_t)(high_offset << 32 | low_offset);
+ if (chunk_offset < last_chunk_offset)
+ return midx_error("chunks are non-monotonic");
+ if (chunk_offset >= trailer_offset)
+ return midx_error("chunks extend beyond the trailer");
+ if (last_chunk != NULL)
+ last_chunk->length = (size_t)(chunk_offset - last_chunk_offset);
+ last_chunk_offset = chunk_offset;
+
+ switch (chunk_id) {
+ case MIDX_PACKFILE_NAMES_ID:
+ chunk_packfile_names.offset = last_chunk_offset;
+ last_chunk = &chunk_packfile_names;
+ break;
+
+ case MIDX_OID_FANOUT_ID:
+ chunk_oid_fanout.offset = last_chunk_offset;
+ last_chunk = &chunk_oid_fanout;
+ break;
+
+ case MIDX_OID_LOOKUP_ID:
+ chunk_oid_lookup.offset = last_chunk_offset;
+ last_chunk = &chunk_oid_lookup;
+ break;
+
+ case MIDX_OBJECT_OFFSETS_ID:
+ chunk_object_offsets.offset = last_chunk_offset;
+ last_chunk = &chunk_object_offsets;
+ break;
+
+ case MIDX_OBJECT_LARGE_OFFSETS_ID:
+ chunk_object_large_offsets.offset = last_chunk_offset;
+ last_chunk = &chunk_object_large_offsets;
+ break;
+
+ default:
+ return midx_error("unrecognized chunk ID");
+ }
+ }
+ last_chunk->length = (size_t)(trailer_offset - last_chunk_offset);
+
+ error = midx_parse_packfile_names(
+ idx, data, ntohl(hdr->packfiles), &chunk_packfile_names);
+ if (error < 0)
+ return error;
+ error = midx_parse_oid_fanout(idx, data, &chunk_oid_fanout);
+ if (error < 0)
+ return error;
+ error = midx_parse_oid_lookup(idx, data, &chunk_oid_lookup);
+ if (error < 0)
+ return error;
+ error = midx_parse_object_offsets(idx, data, &chunk_object_offsets);
+ if (error < 0)
+ return error;
+ error = midx_parse_object_large_offsets(idx, data, &chunk_object_large_offsets);
+ if (error < 0)
+ return error;
+
+ return 0;
+}
+
+int git_midx_open(
+ git_midx_file **idx_out,
+ const char *path)
+{
+ git_midx_file *idx;
+ git_file fd = -1;
+ size_t idx_size;
+ struct stat st;
+ int error;
+
+ /* TODO: properly open the file without access time using O_NOATIME */
+ fd = git_futils_open_ro(path);
+ if (fd < 0)
+ return fd;
+
+ if (p_fstat(fd, &st) < 0) {
+ p_close(fd);
+ git_error_set(GIT_ERROR_ODB, "multi-pack-index file not found - '%s'", path);
+ return -1;
+ }
+
+ if (!S_ISREG(st.st_mode) || !git__is_sizet(st.st_size)) {
+ p_close(fd);
+ git_error_set(GIT_ERROR_ODB, "invalid pack index '%s'", path);
+ return -1;
+ }
+ idx_size = (size_t)st.st_size;
+
+ idx = git__calloc(1, sizeof(git_midx_file));
+ GIT_ERROR_CHECK_ALLOC(idx);
+
+ error = git_str_sets(&idx->filename, path);
+ if (error < 0)
+ return error;
+
+ error = git_futils_mmap_ro(&idx->index_map, fd, 0, idx_size);
+ p_close(fd);
+ if (error < 0) {
+ git_midx_free(idx);
+ return error;
+ }
+
+ if ((error = git_midx_parse(idx, idx->index_map.data, idx_size)) < 0) {
+ git_midx_free(idx);
+ return error;
+ }
+
+ *idx_out = idx;
+ return 0;
+}
+
+bool git_midx_needs_refresh(
+ const git_midx_file *idx,
+ const char *path)
+{
+ git_file fd = -1;
+ struct stat st;
+ ssize_t bytes_read;
+ unsigned char checksum[GIT_HASH_SHA1_SIZE];
+ size_t checksum_size;
+
+ /* TODO: properly open the file without access time using O_NOATIME */
+ fd = git_futils_open_ro(path);
+ if (fd < 0)
+ return true;
+
+ if (p_fstat(fd, &st) < 0) {
+ p_close(fd);
+ return true;
+ }
+
+ if (!S_ISREG(st.st_mode) ||
+ !git__is_sizet(st.st_size) ||
+ (size_t)st.st_size != idx->index_map.len) {
+ p_close(fd);
+ return true;
+ }
+
+ checksum_size = GIT_HASH_SHA1_SIZE;
+ bytes_read = p_pread(fd, checksum, checksum_size, st.st_size - GIT_OID_RAWSZ);
+ p_close(fd);
+
+ if (bytes_read != (ssize_t)checksum_size)
+ return true;
+
+ return (memcmp(checksum, idx->checksum, checksum_size) != 0);
+}
+
+int git_midx_entry_find(
+ git_midx_entry *e,
+ git_midx_file *idx,
+ const git_oid *short_oid,
+ size_t len)
+{
+ int pos, found = 0;
+ size_t pack_index;
+ uint32_t hi, lo;
+ unsigned char *current = NULL;
+ const unsigned char *object_offset;
+ off64_t offset;
+
+ GIT_ASSERT_ARG(idx);
+
+ hi = ntohl(idx->oid_fanout[(int)short_oid->id[0]]);
+ lo = ((short_oid->id[0] == 0x0) ? 0 : ntohl(idx->oid_fanout[(int)short_oid->id[0] - 1]));
+
+ pos = git_pack__lookup_sha1(idx->oid_lookup, GIT_OID_RAWSZ, lo, hi, short_oid->id);
+
+ if (pos >= 0) {
+ /* An object matching exactly the oid was found */
+ found = 1;
+ current = idx->oid_lookup + (pos * GIT_OID_RAWSZ);
+ } else {
+ /* No object was found */
+ /* pos refers to the object with the "closest" oid to short_oid */
+ pos = -1 - pos;
+ if (pos < (int)idx->num_objects) {
+ current = idx->oid_lookup + (pos * GIT_OID_RAWSZ);
+
+ if (!git_oid_raw_ncmp(short_oid->id, current, len))
+ found = 1;
+ }
+ }
+
+ if (found && len != GIT_OID_HEXSZ && pos + 1 < (int)idx->num_objects) {
+ /* Check for ambiguousity */
+ const unsigned char *next = current + GIT_OID_RAWSZ;
+
+ if (!git_oid_raw_ncmp(short_oid->id, next, len))
+ found = 2;
+ }
+
+ if (!found)
+ return git_odb__error_notfound("failed to find offset for multi-pack index entry", short_oid, len);
+ if (found > 1)
+ return git_odb__error_ambiguous("found multiple offsets for multi-pack index entry");
+
+ object_offset = idx->object_offsets + pos * 8;
+ offset = ntohl(*((uint32_t *)(object_offset + 4)));
+ if (idx->object_large_offsets && offset & 0x80000000) {
+ uint32_t object_large_offsets_pos = (uint32_t) (offset ^ 0x80000000);
+ const unsigned char *object_large_offsets_index = idx->object_large_offsets;
+
+ /* Make sure we're not being sent out of bounds */
+ if (object_large_offsets_pos >= idx->num_object_large_offsets)
+ return git_odb__error_notfound("invalid index into the object large offsets table", short_oid, len);
+
+ object_large_offsets_index += 8 * object_large_offsets_pos;
+
+ offset = (((uint64_t)ntohl(*((uint32_t *)(object_large_offsets_index + 0)))) << 32) |
+ ntohl(*((uint32_t *)(object_large_offsets_index + 4)));
+ }
+ pack_index = ntohl(*((uint32_t *)(object_offset + 0)));
+ if (pack_index >= git_vector_length(&idx->packfile_names))
+ return midx_error("invalid index into the packfile names table");
+ e->pack_index = pack_index;
+ e->offset = offset;
+ git_oid_fromraw(&e->sha1, current);
+ return 0;
+}
+
+int git_midx_foreach_entry(
+ git_midx_file *idx,
+ git_odb_foreach_cb cb,
+ void *data)
+{
+ git_oid oid;
+ size_t i;
+ int error;
+
+ GIT_ASSERT_ARG(idx);
+
+ for (i = 0; i < idx->num_objects; ++i) {
+ if ((error = git_oid_fromraw(&oid, &idx->oid_lookup[i * GIT_OID_RAWSZ])) < 0)
+ return error;
+
+ if ((error = cb(&oid, data)) != 0)
+ return git_error_set_after_callback(error);
+ }
+
+ return error;
+}
+
+int git_midx_close(git_midx_file *idx)
+{
+ GIT_ASSERT_ARG(idx);
+
+ if (idx->index_map.data)
+ git_futils_mmap_free(&idx->index_map);
+
+ git_vector_free(&idx->packfile_names);
+
+ return 0;
+}
+
+void git_midx_free(git_midx_file *idx)
+{
+ if (!idx)
+ return;
+
+ git_str_dispose(&idx->filename);
+ git_midx_close(idx);
+ git__free(idx);
+}
+
+static int packfile__cmp(const void *a_, const void *b_)
+{
+ const struct git_pack_file *a = a_;
+ const struct git_pack_file *b = b_;
+
+ return strcmp(a->pack_name, b->pack_name);
+}
+
+int git_midx_writer_new(
+ git_midx_writer **out,
+ const char *pack_dir)
+{
+ git_midx_writer *w = git__calloc(1, sizeof(git_midx_writer));
+ GIT_ERROR_CHECK_ALLOC(w);
+
+ if (git_str_sets(&w->pack_dir, pack_dir) < 0) {
+ git__free(w);
+ return -1;
+ }
+ git_fs_path_squash_slashes(&w->pack_dir);
+
+ if (git_vector_init(&w->packs, 0, packfile__cmp) < 0) {
+ git_str_dispose(&w->pack_dir);
+ git__free(w);
+ return -1;
+ }
+
+ *out = w;
+ return 0;
+}
+
+void git_midx_writer_free(git_midx_writer *w)
+{
+ struct git_pack_file *p;
+ size_t i;
+
+ if (!w)
+ return;
+
+ git_vector_foreach (&w->packs, i, p)
+ git_mwindow_put_pack(p);
+ git_vector_free(&w->packs);
+ git_str_dispose(&w->pack_dir);
+ git__free(w);
+}
+
+int git_midx_writer_add(
+ git_midx_writer *w,
+ const char *idx_path)
+{
+ git_str idx_path_buf = GIT_STR_INIT;
+ int error;
+ struct git_pack_file *p;
+
+ error = git_fs_path_prettify(&idx_path_buf, idx_path, git_str_cstr(&w->pack_dir));
+ if (error < 0)
+ return error;
+
+ error = git_mwindow_get_pack(&p, git_str_cstr(&idx_path_buf));
+ git_str_dispose(&idx_path_buf);
+ if (error < 0)
+ return error;
+
+ error = git_vector_insert(&w->packs, p);
+ if (error < 0) {
+ git_mwindow_put_pack(p);
+ return error;
+ }
+
+ return 0;
+}
+
+typedef git_array_t(git_midx_entry) object_entry_array_t;
+
+struct object_entry_cb_state {
+ uint32_t pack_index;
+ object_entry_array_t *object_entries_array;
+};
+
+static int object_entry__cb(const git_oid *oid, off64_t offset, void *data)
+{
+ struct object_entry_cb_state *state = (struct object_entry_cb_state *)data;
+
+ git_midx_entry *entry = git_array_alloc(*state->object_entries_array);
+ GIT_ERROR_CHECK_ALLOC(entry);
+
+ git_oid_cpy(&entry->sha1, oid);
+ entry->offset = offset;
+ entry->pack_index = state->pack_index;
+
+ return 0;
+}
+
+static int object_entry__cmp(const void *a_, const void *b_)
+{
+ const git_midx_entry *a = (const git_midx_entry *)a_;
+ const git_midx_entry *b = (const git_midx_entry *)b_;
+
+ return git_oid_cmp(&a->sha1, &b->sha1);
+}
+
+static int write_offset(off64_t offset, midx_write_cb write_cb, void *cb_data)
+{
+ int error;
+ uint32_t word;
+
+ word = htonl((uint32_t)((offset >> 32) & 0xffffffffu));
+ error = write_cb((const char *)&word, sizeof(word), cb_data);
+ if (error < 0)
+ return error;
+ word = htonl((uint32_t)((offset >> 0) & 0xffffffffu));
+ error = write_cb((const char *)&word, sizeof(word), cb_data);
+ if (error < 0)
+ return error;
+
+ return 0;
+}
+
+static int write_chunk_header(int chunk_id, off64_t offset, midx_write_cb write_cb, void *cb_data)
+{
+ uint32_t word = htonl(chunk_id);
+ int error = write_cb((const char *)&word, sizeof(word), cb_data);
+ if (error < 0)
+ return error;
+ return write_offset(offset, write_cb, cb_data);
+
+ return 0;
+}
+
+static int midx_write_buf(const char *buf, size_t size, void *data)
+{
+ git_str *b = (git_str *)data;
+ return git_str_put(b, buf, size);
+}
+
+struct midx_write_hash_context {
+ midx_write_cb write_cb;
+ void *cb_data;
+ git_hash_ctx *ctx;
+};
+
+static int midx_write_hash(const char *buf, size_t size, void *data)
+{
+ struct midx_write_hash_context *ctx = (struct midx_write_hash_context *)data;
+ int error;
+
+ error = git_hash_update(ctx->ctx, buf, size);
+ if (error < 0)
+ return error;
+
+ return ctx->write_cb(buf, size, ctx->cb_data);
+}
+
+static int midx_write(
+ git_midx_writer *w,
+ midx_write_cb write_cb,
+ void *cb_data)
+{
+ int error = 0;
+ size_t i;
+ struct git_pack_file *p;
+ struct git_midx_header hdr = {0};
+ uint32_t oid_fanout_count;
+ uint32_t object_large_offsets_count;
+ uint32_t oid_fanout[256];
+ off64_t offset;
+ git_str packfile_names = GIT_STR_INIT,
+ oid_lookup = GIT_STR_INIT,
+ object_offsets = GIT_STR_INIT,
+ object_large_offsets = GIT_STR_INIT;
+ unsigned char checksum[GIT_HASH_SHA1_SIZE];
+ size_t checksum_size;
+ git_midx_entry *entry;
+ object_entry_array_t object_entries_array = GIT_ARRAY_INIT;
+ git_vector object_entries = GIT_VECTOR_INIT;
+ git_hash_ctx ctx;
+ struct midx_write_hash_context hash_cb_data = {0};
+
+ hdr.signature = htonl(MIDX_SIGNATURE);
+ hdr.version = MIDX_VERSION;
+ hdr.object_id_version = MIDX_OBJECT_ID_VERSION;
+ hdr.base_midx_files = 0;
+
+ hash_cb_data.write_cb = write_cb;
+ hash_cb_data.cb_data = cb_data;
+ hash_cb_data.ctx = &ctx;
+
+ checksum_size = GIT_HASH_SHA1_SIZE;
+ error = git_hash_ctx_init(&ctx, GIT_HASH_ALGORITHM_SHA1);
+ if (error < 0)
+ return error;
+ cb_data = &hash_cb_data;
+ write_cb = midx_write_hash;
+
+ git_vector_sort(&w->packs);
+ git_vector_foreach (&w->packs, i, p) {
+ git_str relative_index = GIT_STR_INIT;
+ struct object_entry_cb_state state = {0};
+ size_t path_len;
+
+ state.pack_index = (uint32_t)i;
+ state.object_entries_array = &object_entries_array;
+
+ error = git_str_sets(&relative_index, p->pack_name);
+ if (error < 0)
+ goto cleanup;
+ error = git_fs_path_make_relative(&relative_index, git_str_cstr(&w->pack_dir));
+ if (error < 0) {
+ git_str_dispose(&relative_index);
+ goto cleanup;
+ }
+ path_len = git_str_len(&relative_index);
+ if (path_len <= strlen(".pack") || git__suffixcmp(git_str_cstr(&relative_index), ".pack") != 0) {
+ git_str_dispose(&relative_index);
+ git_error_set(GIT_ERROR_INVALID, "invalid packfile name: '%s'", p->pack_name);
+ error = -1;
+ goto cleanup;
+ }
+ path_len -= strlen(".pack");
+
+ git_str_put(&packfile_names, git_str_cstr(&relative_index), path_len);
+ git_str_puts(&packfile_names, ".idx");
+ git_str_putc(&packfile_names, '\0');
+ git_str_dispose(&relative_index);
+
+ error = git_pack_foreach_entry_offset(p, object_entry__cb, &state);
+ if (error < 0)
+ goto cleanup;
+ }
+
+ /* Sort the object entries. */
+ error = git_vector_init(&object_entries, git_array_size(object_entries_array), object_entry__cmp);
+ if (error < 0)
+ goto cleanup;
+ git_array_foreach (object_entries_array, i, entry) {
+ if ((error = git_vector_set(NULL, &object_entries, i, entry)) < 0)
+ goto cleanup;
+ }
+ git_vector_set_sorted(&object_entries, 0);
+ git_vector_sort(&object_entries);
+ git_vector_uniq(&object_entries, NULL);
+
+ /* Pad the packfile names so it is a multiple of four. */
+ while (git_str_len(&packfile_names) & 3)
+ git_str_putc(&packfile_names, '\0');
+
+ /* Fill the OID Fanout table. */
+ oid_fanout_count = 0;
+ for (i = 0; i < 256; i++) {
+ while (oid_fanout_count < git_vector_length(&object_entries) &&
+ ((const git_midx_entry *)git_vector_get(&object_entries, oid_fanout_count))->sha1.id[0] <= i)
+ ++oid_fanout_count;
+ oid_fanout[i] = htonl(oid_fanout_count);
+ }
+
+ /* Fill the OID Lookup table. */
+ git_vector_foreach (&object_entries, i, entry) {
+ error = git_str_put(&oid_lookup, (char *)&entry->sha1.id, GIT_OID_RAWSZ);
+ if (error < 0)
+ goto cleanup;
+ }
+
+ /* Fill the Object Offsets and Object Large Offsets tables. */
+ object_large_offsets_count = 0;
+ git_vector_foreach (&object_entries, i, entry) {
+ uint32_t word;
+
+ word = htonl((uint32_t)entry->pack_index);
+ error = git_str_put(&object_offsets, (const char *)&word, sizeof(word));
+ if (error < 0)
+ goto cleanup;
+ if (entry->offset >= 0x80000000l) {
+ word = htonl(0x80000000u | object_large_offsets_count++);
+ if ((error = write_offset(entry->offset, midx_write_buf, &object_large_offsets)) < 0)
+ goto cleanup;
+ } else {
+ word = htonl((uint32_t)entry->offset & 0x7fffffffu);
+ }
+
+ error = git_str_put(&object_offsets, (const char *)&word, sizeof(word));
+ if (error < 0)
+ goto cleanup;
+ }
+
+ /* Write the header. */
+ hdr.packfiles = htonl((uint32_t)git_vector_length(&w->packs));
+ hdr.chunks = 4;
+ if (git_str_len(&object_large_offsets) > 0)
+ hdr.chunks++;
+ error = write_cb((const char *)&hdr, sizeof(hdr), cb_data);
+ if (error < 0)
+ goto cleanup;
+
+ /* Write the chunk headers. */
+ offset = sizeof(hdr) + (hdr.chunks + 1) * 12;
+ error = write_chunk_header(MIDX_PACKFILE_NAMES_ID, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+ offset += git_str_len(&packfile_names);
+ error = write_chunk_header(MIDX_OID_FANOUT_ID, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+ offset += sizeof(oid_fanout);
+ error = write_chunk_header(MIDX_OID_LOOKUP_ID, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+ offset += git_str_len(&oid_lookup);
+ error = write_chunk_header(MIDX_OBJECT_OFFSETS_ID, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+ offset += git_str_len(&object_offsets);
+ if (git_str_len(&object_large_offsets) > 0) {
+ error = write_chunk_header(MIDX_OBJECT_LARGE_OFFSETS_ID, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+ offset += git_str_len(&object_large_offsets);
+ }
+ error = write_chunk_header(0, offset, write_cb, cb_data);
+ if (error < 0)
+ goto cleanup;
+
+ /* Write all the chunks. */
+ error = write_cb(git_str_cstr(&packfile_names), git_str_len(&packfile_names), cb_data);
+ if (error < 0)
+ goto cleanup;
+ error = write_cb((const char *)oid_fanout, sizeof(oid_fanout), cb_data);
+ if (error < 0)
+ goto cleanup;
+ error = write_cb(git_str_cstr(&oid_lookup), git_str_len(&oid_lookup), cb_data);
+ if (error < 0)
+ goto cleanup;
+ error = write_cb(git_str_cstr(&object_offsets), git_str_len(&object_offsets), cb_data);
+ if (error < 0)
+ goto cleanup;
+ error = write_cb(git_str_cstr(&object_large_offsets), git_str_len(&object_large_offsets), cb_data);
+ if (error < 0)
+ goto cleanup;
+
+ /* Finalize the checksum and write the trailer. */
+ error = git_hash_final(checksum, &ctx);
+ if (error < 0)
+ goto cleanup;
+ error = write_cb((char *)checksum, checksum_size, cb_data);
+ if (error < 0)
+ goto cleanup;
+
+cleanup:
+ git_array_clear(object_entries_array);
+ git_vector_free(&object_entries);
+ git_str_dispose(&packfile_names);
+ git_str_dispose(&oid_lookup);
+ git_str_dispose(&object_offsets);
+ git_str_dispose(&object_large_offsets);
+ git_hash_ctx_cleanup(&ctx);
+ return error;
+}
+
+static int midx_write_filebuf(const char *buf, size_t size, void *data)
+{
+ git_filebuf *f = (git_filebuf *)data;
+ return git_filebuf_write(f, buf, size);
+}
+
+int git_midx_writer_commit(
+ git_midx_writer *w)
+{
+ int error;
+ int filebuf_flags = GIT_FILEBUF_DO_NOT_BUFFER;
+ git_str midx_path = GIT_STR_INIT;
+ git_filebuf output = GIT_FILEBUF_INIT;
+
+ error = git_str_joinpath(&midx_path, git_str_cstr(&w->pack_dir), "multi-pack-index");
+ if (error < 0)
+ return error;
+
+ if (git_repository__fsync_gitdir)
+ filebuf_flags |= GIT_FILEBUF_FSYNC;
+ error = git_filebuf_open(&output, git_str_cstr(&midx_path), filebuf_flags, 0644);
+ git_str_dispose(&midx_path);
+ if (error < 0)
+ return error;
+
+ error = midx_write(w, midx_write_filebuf, &output);
+ if (error < 0) {
+ git_filebuf_cleanup(&output);
+ return error;
+ }
+
+ return git_filebuf_commit(&output);
+}
+
+int git_midx_writer_dump(
+ git_buf *midx,
+ git_midx_writer *w)
+{
+ git_str str = GIT_STR_INIT;
+ int error;
+
+ if ((error = git_buf_tostr(&str, midx)) < 0 ||
+ (error = midx_write(w, midx_write_buf, &str)) == 0)
+ error = git_buf_fromstr(midx, &str);
+
+ git_str_dispose(&str);
+ return error;
+}
projects / libgit2.git / blobdiff