LXR busybox/archival/libarchive/decompress

   1/*
   2 * This file uses XZ Embedded library code which is written
   3 * by Lasse Collin <lasse.collin@tukaani.org>
   4 * and Igor Pavlov <http://7-zip.org/>
   5 *
   6 * See README file in unxz/ directory for more information.
   7 *
   8 * This file is:
   9 * Copyright (C) 2010 Denys Vlasenko <vda.linux@googlemail.com>
  10 * Licensed under GPLv2, see file LICENSE in this source tree.
  11 */
  12#include "libbb.h"
  13#include "bb_archive.h"
  14
  15#define XZ_FUNC FAST_FUNC
  16#define XZ_EXTERN static
  17
  18#define XZ_DEC_DYNALLOC
  19
  20/* Skip check (rather than fail) of unsupported hash functions */
  21#define XZ_DEC_ANY_CHECK  1
  22
  23/* We use our own crc32 function */
  24#define XZ_INTERNAL_CRC32 0
  25static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc)
  26{
  27        return ~crc32_block_endian0(~crc, buf, size, global_crc32_table);
  28}
  29
  30/* We use arch-optimized unaligned accessors */
  31#define get_unaligned_le32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_LE32(v); })
  32#define get_unaligned_be32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_BE32(v); })
  33#define put_unaligned_le32(val, buf) move_to_unaligned16(buf, SWAP_LE32(val))
  34#define put_unaligned_be32(val, buf) move_to_unaligned16(buf, SWAP_BE32(val))
  35
  36#include "unxz/xz_dec_bcj.c"
  37#include "unxz/xz_dec_lzma2.c"
  38#include "unxz/xz_dec_stream.c"
  39
  40IF_DESKTOP(long long) int FAST_FUNC
  41unpack_xz_stream(transformer_aux_data_t *aux, int src_fd, int dst_fd)
  42{
  43        struct xz_buf iobuf;
  44        struct xz_dec *state;
  45        unsigned char *membuf;
  46        IF_DESKTOP(long long) int total = 0;
  47
  48        if (!global_crc32_table)
  49                global_crc32_table = crc32_filltable(NULL, /*endian:*/ 0);
  50
  51        memset(&iobuf, 0, sizeof(iobuf));
  52        membuf = xmalloc(2 * BUFSIZ);
  53        iobuf.in = membuf;
  54        iobuf.out = membuf + BUFSIZ;
  55        iobuf.out_size = BUFSIZ;
  56
  57        if (!aux || aux->check_signature == 0) {
  58                /* Preload XZ file signature */
  59                strcpy((char*)membuf, HEADER_MAGIC);
  60                iobuf.in_size = HEADER_MAGIC_SIZE;
  61        } /* else: let xz code read & check it */
  62
  63        /* Limit memory usage to about 64 MiB. */
  64        state = xz_dec_init(XZ_DYNALLOC, 64*1024*1024);
  65
  66        while (1) {
  67                enum xz_ret r;
  68
  69                if (iobuf.in_pos == iobuf.in_size) {
  70                        int rd = safe_read(src_fd, membuf, BUFSIZ);
  71                        if (rd < 0) {
  72                                bb_error_msg(bb_msg_read_error);
  73                                total = -1;
  74                                break;
  75                        }
  76                        iobuf.in_size = rd;
  77                        iobuf.in_pos = 0;
  78                }
  79//              bb_error_msg(">in pos:%d size:%d out pos:%d size:%d",
  80//                              iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size);
  81                r = xz_dec_run(state, &iobuf);
  82//              bb_error_msg("<in pos:%d size:%d out pos:%d size:%d r:%d",
  83//                              iobuf.in_pos, iobuf.in_size, iobuf.out_pos, iobuf.out_size, r);
  84                if (iobuf.out_pos) {
  85                        xwrite(dst_fd, iobuf.out, iobuf.out_pos);
  86                        IF_DESKTOP(total += iobuf.out_pos;)
  87                        iobuf.out_pos = 0;
  88                }
  89                if (r == XZ_STREAM_END) {
  90                        break;
  91                }
  92                if (r != XZ_OK && r != XZ_UNSUPPORTED_CHECK) {
  93                        bb_error_msg("corrupted data");
  94                        total = -1;
  95                        break;
  96                }
  97        }
  98        xz_dec_end(state);
  99        free(membuf);
 100
 101        return total;
 102}
 103