lzma.c

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/*
 * coreboot interface to memory-saving variant of LZMA decoder
 *
 * Copyright (C) 2006 Carl-Daniel Hailfinger
 * Released under the GNU GPL v2 or later
 *
 * Parts of this file are based on C/7zip/Compress/LZMA_C/LzmaTest.c from the
 * LZMA SDK 4.42, which is written and distributed to public domain by Igor
 * Pavlov.
 *
 */
 
#include <console/console.h>
#include <string.h>
#include <lib.h>
 
#include "lzmadecode.h"
 
size_t ulzman(const void *src, size_t srcn, void *dst, size_t dstn)
{
        unsigned char properties[LZMA_PROPERTIES_SIZE];
        const int data_offset = LZMA_PROPERTIES_SIZE + 8;
        UInt32 outSize;
        SizeT inProcessed;
        SizeT outProcessed;
        int res;
        CLzmaDecoderState state;
        SizeT mallocneeds;
        static unsigned char scratchpad[15980];
        const unsigned char *cp;
 
        if (srcn < data_offset) {
                printk(BIOS_WARNING, "lzma: Input too small.\n");
                return 0;
        }
 
        memcpy(properties, src, LZMA_PROPERTIES_SIZE);
        /* The outSize in LZMA stream is a 64bit integer stored in little-endian
         * (ref: lzma.cc@LZMACompress: put_64). To prevent accessing by
         * unaligned memory address and to load in correct endianness, read each
         * byte and re-construct. */
        cp = src + LZMA_PROPERTIES_SIZE;
        outSize = cp[3] << 24 | cp[2] << 16 | cp[1] << 8 | cp[0];
        if (outSize > dstn)
                outSize = dstn;
        if (LzmaDecodeProperties(&state.Properties, properties,
                                 LZMA_PROPERTIES_SIZE) != LZMA_RESULT_OK) {
                printk(BIOS_WARNING, "lzma: Incorrect stream properties.\n");
                return 0;
        }
        mallocneeds = (LzmaGetNumProbs(&state.Properties) * sizeof(CProb));
        if (mallocneeds > 15980) {
                printk(BIOS_WARNING, "lzma: Decoder scratchpad too small!\n");
                return 0;
        }
        state.Probs = (CProb *)scratchpad;
        res = LzmaDecode(&state, src + data_offset, srcn - data_offset,
                         &inProcessed, dst, outSize, &outProcessed);
        if (res != 0) {
                printk(BIOS_WARNING, "lzma: Decoding error = %d\n", res);
                return 0;
        }
        return outProcessed;
}