#include <stdio.h> #include <stdint.h> #include <stdlib.h> #include <string.h> #include "../common.h" #include "C/LzmaDec.h" #include "C/LzmaEnc.h" #define L (uint64_t) static inline uint64_t get_64(const void *p) { const unsigned char *data = (const unsigned char *)p; return (L data[0]) | (L data[1] << 8) | (L data[2] << 16) | (L data[3] << 24) | (L data [4] << 32) | (L data[5] << 40) | (L data[6] << 48) | (L data[7] << 56); } static void put_64(void *p, uint64_t value) { unsigned char *data = (unsigned char *)p; data[0] = value & 0xff; data[1] = (value >> 8) & 0xff; data[2] = (value >> 16) & 0xff; data[3] = (value >> 24) & 0xff; data[4] = (value >> 32) & 0xff; data[5] = (value >> 40) & 0xff; data[6] = (value >> 48) & 0xff; data[7] = (value >> 56) & 0xff; } /* Memory Allocation API */ static void *SzAlloc(unused void *u, size_t size) { return malloc(size); } static void SzFree(unused void *u, void *address) { free(address); } static struct ISzAlloc LZMAalloc = { SzAlloc, SzFree }; /* Streaming API */ struct vector_t { char *p; size_t pos; size_t size; }; static struct vector_t instream, outstream; static SRes Read(unused void *u, void *buf, size_t *size) { if ((instream.size - instream.pos) < *size) *size = instream.size - instream.pos; memcpy(buf, instream.p + instream.pos, *size); instream.pos += *size; return SZ_OK; } static size_t Write(unused void *u, const void *buf, size_t size) { if(outstream.size - outstream.pos < size) size = outstream.size - outstream.pos; memcpy(outstream.p + outstream.pos, buf, size); outstream.pos += size; return size; } static struct ISeqInStream is = { Read }; static struct ISeqOutStream os = { Write }; /** * Compress a buffer with lzma * Don't copy the result back if it is too large. * @param in a pointer to the buffer * @param in_len the length in bytes * @param out a pointer to a buffer of at least size in_len * @param out_len a pointer to the compressed length of in */ int do_lzma_compress(char *in, int in_len, char *out, int *out_len) { if (in_len == 0) { ERROR("LZMA: Input length is zero.\n"); return -1; } struct CLzmaEncProps props; LzmaEncProps_Init(&props); props.dictSize = in_len; props.pb = 0; /* PosStateBits, default: 2, range: 0..4 */ props.lp = 0; /* LiteralPosStateBits, default: 0, range: 0..4 */ props.lc = 1; /* LiteralContextBits, default: 3, range: 0..8 */ props.fb = 273; /* NumFastBytes */ props.mc = 0; /* MatchFinderCycles, default: 0 */ props.algo = 1; /* AlgorithmNo, apparently, 0 and 1 are valid values. 0 = fast mode */ props.numThreads = 1; switch (props.algo) { case 0: // quick: HC4 props.btMode = 0; props.level = 1; break; case 1: // full: BT4 default: props.level = 9; props.btMode = 1; props.numHashBytes = 4; break; } CLzmaEncHandle p = LzmaEnc_Create(&LZMAalloc); int res = LzmaEnc_SetProps(p, &props); if (res != SZ_OK) { ERROR("LZMA: LzmaEnc_SetProps failed.\n"); return -1; } unsigned char propsEncoded[LZMA_PROPS_SIZE + 8]; size_t propsSize = sizeof propsEncoded; res = LzmaEnc_WriteProperties(p, propsEncoded, &propsSize); if (res != SZ_OK) { ERROR("LZMA: LzmaEnc_WriteProperties failed.\n"); return -1; } instream.p = in; instream.pos = 0; instream.size = in_len; outstream.p = out; outstream.pos = 0; outstream.size = in_len; put_64(propsEncoded + LZMA_PROPS_SIZE, in_len); Write(&os, propsEncoded, LZMA_PROPS_SIZE+8); res = LzmaEnc_Encode(p, &os, &is, 0, &LZMAalloc, &LZMAalloc); LzmaEnc_Destroy(p, &LZMAalloc, &LZMAalloc); if (res != SZ_OK) { ERROR("LZMA: LzmaEnc_Encode failed %d.\n", res); return -1; } *out_len = outstream.pos; return 0; } int do_lzma_uncompress(char *dst, int dst_len, char *src, int src_len) { if (src_len <= LZMA_PROPS_SIZE + 8) { ERROR("LZMA: Input length is too small.\n"); return -1; } uint64_t out_sizemax = get_64(&src[LZMA_PROPS_SIZE]); if (out_sizemax > (size_t) dst_len) { ERROR("Not copying %d bytes to %d-byte buffer!\n", (unsigned int)out_sizemax, dst_len); return -1; } enum ELzmaStatus status; size_t destlen = out_sizemax; size_t srclen = src_len - (LZMA_PROPS_SIZE + 8); int res = LzmaDecode((uint8_t *) dst, &destlen, (uint8_t *) &src[LZMA_PROPS_SIZE + 8], &srclen, (uint8_t *) &src[0], LZMA_PROPS_SIZE, LZMA_FINISH_END, &status, &LZMAalloc); if (res != SZ_OK) { ERROR("Error while decompressing.\n"); return -1; } return 0; }