/*
* This file is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2,
* as published by the Free Software Foundation.
*
* In addition to the permissions in the GNU General Public License,
* the authors give you unlimited permission to link the compiled
* version of this file into combinations with other programs,
* and to distribute those combinations without any restriction
* coming from the use of this file. (The General Public License
* restrictions do apply in other respects; for example, they cover
* modification of the file, and distribution when not linked into
* a combined executable.)
*
* This file is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "git2/indexer.h"
#include "git2/object.h"
#include "git2/zlib.h"
#include "git2/oid.h"
#include "common.h"
#include "pack.h"
#include "mwindow.h"
#include "posix.h"
#include "pack.h"
#include "filebuf.h"
#include "sha1.h"
#define UINT31_MAX (0x7FFFFFFF)
struct entry {
git_oid oid;
uint32_t crc;
uint32_t offset;
uint64_t offset_long;
};
typedef struct git_indexer {
struct git_pack_file *pack;
struct stat st;
struct git_pack_header hdr;
size_t nr_objects;
git_vector objects;
git_filebuf file;
unsigned int fanout[256];
git_oid hash;
} git_indexer;
const git_oid *git_indexer_hash(git_indexer *idx)
{
return &idx->hash;
}
static int parse_header(git_indexer *idx)
{
int error;
/* Verify we recognize this pack file format. */
if ((error = p_read(idx->pack->mwf.fd, &idx->hdr, sizeof(idx->hdr))) < GIT_SUCCESS)
return git__rethrow(error, "Failed to read in pack header");
if (idx->hdr.hdr_signature != ntohl(PACK_SIGNATURE))
return git__throw(GIT_EOBJCORRUPTED, "Wrong pack signature");
if (!pack_version_ok(idx->hdr.hdr_version))
return git__throw(GIT_EOBJCORRUPTED, "Wrong pack version");
return GIT_SUCCESS;
}
int objects_cmp(const void *a, const void *b)
{
const struct entry *entrya = a;
const struct entry *entryb = b;
return git_oid_cmp(&entrya->oid, &entryb->oid);
}
int git_indexer_new(git_indexer **out, const char *packname)
{
git_indexer *idx;
unsigned int namelen;
int ret, error;
if (git_path_root(packname) < 0)
return git__throw(GIT_EINVALIDPATH, "Path is not absolute");
idx = git__malloc(sizeof(git_indexer));
if (idx == NULL)
return GIT_ENOMEM;
memset(idx, 0x0, sizeof(*idx));
namelen = strlen(packname);
idx->pack = git__malloc(sizeof(struct git_pack_file) + namelen + 1);
if (idx->pack == NULL) {
error = GIT_ENOMEM;
goto cleanup;
}
memset(idx->pack, 0x0, sizeof(struct git_pack_file));
memcpy(idx->pack->pack_name, packname, namelen + 1);
ret = p_stat(packname, &idx->st);
if (ret < 0) {
if (errno == ENOENT)
error = git__throw(GIT_ENOTFOUND, "Failed to stat packfile. File not found");
else
error = git__throw(GIT_EOSERR, "Failed to stat packfile.");
goto cleanup;
}
ret = p_open(idx->pack->pack_name, O_RDONLY);
if (ret < 0) {
error = git__throw(GIT_EOSERR, "Failed to open packfile");
goto cleanup;
}
idx->pack->mwf.fd = ret;
idx->pack->mwf.size = (git_off_t)idx->st.st_size;
error = parse_header(idx);
if (error < GIT_SUCCESS) {
error = git__rethrow(error, "Failed to parse packfile header");
goto cleanup;
}
idx->nr_objects = ntohl(idx->hdr.hdr_entries);
error = git_vector_init(&idx->objects, idx->nr_objects, objects_cmp);
if (error < GIT_SUCCESS) {
goto cleanup;
}
*out = idx;
return GIT_SUCCESS;
cleanup:
git_indexer_free(idx);
return error;
}
static void index_path(char *path, git_indexer *idx)
{
char *ptr;
const char prefix[] = "pack-", suffix[] = ".idx\0";
ptr = strrchr(path, '/') + 1;
memcpy(ptr, prefix, STRLEN(prefix));
ptr += STRLEN(prefix);
git_oid_fmt(ptr, &idx->hash);
ptr += GIT_OID_HEXSZ;
memcpy(ptr, suffix, STRLEN(suffix));
}
int git_indexer_write(git_indexer *idx)
{
git_mwindow *w = NULL;
int error, namelen;
unsigned int i, long_offsets = 0, left;
struct git_pack_idx_header hdr;
char filename[GIT_PATH_MAX];
struct entry *entry;
void *packfile_hash;
git_oid file_hash;
SHA_CTX ctx;
git_vector_sort(&idx->objects);
namelen = strlen(idx->pack->pack_name);
memcpy(filename, idx->pack->pack_name, namelen);
memcpy(filename + namelen - STRLEN("pack"), "idx\0", STRLEN("idx\0"));
error = git_filebuf_open(&idx->file, filename, GIT_FILEBUF_HASH_CONTENTS);
/* Write out the header */
hdr.idx_signature = htonl(PACK_IDX_SIGNATURE);
hdr.idx_version = htonl(2);
error = git_filebuf_write(&idx->file, &hdr, sizeof(hdr));
/* Write out the fanout table */
for (i = 0; i < 256; ++i) {
uint32_t n = htonl(idx->fanout[i]);
error = git_filebuf_write(&idx->file, &n, sizeof(n));
if (error < GIT_SUCCESS)
goto cleanup;
}
/* Write out the object names (SHA-1 hashes) */
SHA1_Init(&ctx);
git_vector_foreach(&idx->objects, i, entry) {
error = git_filebuf_write(&idx->file, &entry->oid, sizeof(git_oid));
SHA1_Update(&ctx, &entry->oid, GIT_OID_RAWSZ);
if (error < GIT_SUCCESS)
goto cleanup;
}
SHA1_Final(idx->hash.id, &ctx);
/* Write out the CRC32 values */
git_vector_foreach(&idx->objects, i, entry) {
error = git_filebuf_write(&idx->file, &entry->crc, sizeof(uint32_t));
if (error < GIT_SUCCESS)
goto cleanup;
}
/* Write out the offsets */
git_vector_foreach(&idx->objects, i, entry) {
uint32_t n;
if (entry->offset == UINT32_MAX)
n = htonl(0x80000000 | long_offsets++);
else
n = htonl(entry->offset);
error = git_filebuf_write(&idx->file, &n, sizeof(uint32_t));
if (error < GIT_SUCCESS)
goto cleanup;
}
/* Write out the long offsets */
git_vector_foreach(&idx->objects, i, entry) {
uint32_t split[2];
if (entry->offset != UINT32_MAX)
continue;
split[0] = htonl(entry->offset_long >> 32);
split[1] = htonl(entry->offset_long & 0xffffffff);
error = git_filebuf_write(&idx->file, &split, sizeof(uint32_t) * 2);
if (error < GIT_SUCCESS)
goto cleanup;
}
/* Write out the packfile trailer */
packfile_hash = git_mwindow_open(&idx->pack->mwf, &w, idx->st.st_size - GIT_OID_RAWSZ, GIT_OID_RAWSZ, &left);
if (packfile_hash == NULL) {
error = git__rethrow(GIT_ENOMEM, "Failed to open window to packfile hash");
goto cleanup;
}
memcpy(&file_hash, packfile_hash, GIT_OID_RAWSZ);
git_mwindow_close(&w);
error = git_filebuf_write(&idx->file, &file_hash, sizeof(git_oid));
/* Write out the index sha */
error = git_filebuf_hash(&file_hash, &idx->file);
if (error < GIT_SUCCESS)
goto cleanup;
error = git_filebuf_write(&idx->file, &file_hash, sizeof(git_oid));
if (error < GIT_SUCCESS)
goto cleanup;
/* Figure out what the final name should be */
index_path(filename, idx);
/* Commit file */
error = git_filebuf_commit_at(&idx->file, filename);
cleanup:
if (error < GIT_SUCCESS)
git_filebuf_cleanup(&idx->file);
return error;
}
int git_indexer_run(git_indexer *idx, git_indexer_stats *stats)
{
git_mwindow_file *mwf;
off_t off = sizeof(struct git_pack_header);
int error;
struct entry *entry;
unsigned int left, processed;
assert(idx && stats);
mwf = &idx->pack->mwf;
error = git_mwindow_file_register(mwf);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to register mwindow file");
stats->total = idx->nr_objects;
stats->processed = processed = 0;
while (processed < idx->nr_objects) {
git_rawobj obj;
git_oid oid;
git_mwindow *w = NULL;
char hdr[512] = {0}; /* FIXME: How long should this be? */
int i, hdr_len;
off_t entry_start = off;
void *packed;
size_t entry_size;
entry = git__malloc(sizeof(struct entry));
memset(entry, 0x0, sizeof(struct entry));
if (off > UINT31_MAX) {
entry->offset = UINT32_MAX;
entry->offset_long = off;
} else {
entry->offset = off;
}
error = git_packfile_unpack(&obj, idx->pack, &off);
if (error < GIT_SUCCESS) {
error = git__rethrow(error, "Failed to unpack object");
goto cleanup;
}
error = git_odb__hash_obj(&oid, hdr, sizeof(hdr), &hdr_len, &obj);
if (error < GIT_SUCCESS) {
error = git__rethrow(error, "Failed to hash object");
goto cleanup;
}
git_oid_cpy(&entry->oid, &oid);
entry->crc = crc32(0L, Z_NULL, 0);
entry_size = off - entry_start;
packed = git_mwindow_open(mwf, &w, entry_start, entry_size, &left);
if (packed == NULL) {
error = git__rethrow(error, "Failed to open window to read packed data");
goto cleanup;
}
entry->crc = htonl(crc32(entry->crc, packed, entry_size));
git_mwindow_close(&w);
/* Add the object to the list */
error = git_vector_insert(&idx->objects, entry);
if (error < GIT_SUCCESS) {
error = git__rethrow(error, "Failed to add entry to list");
goto cleanup;
}
for (i = oid.id[0]; i < 256; ++i) {
idx->fanout[i]++;
}
free(obj.data);
stats->processed = ++processed;
}
cleanup:
git_mwindow_free_all(mwf);
return error;
}
void git_indexer_free(git_indexer *idx)
{
unsigned int i;
struct entry *e;
p_close(idx->pack->mwf.fd);
git_vector_foreach(&idx->objects, i, e)
free(e);
git_vector_free(&idx->objects);
free(idx->pack);
free(idx);
}
