| /* XzIn.c - Xz input |
| 2009-06-19 : Igor Pavlov : Public domain */ |
| |
| #include <string.h> |
| |
| #include "7zCrc.h" |
| #include "CpuArch.h" |
| #include "Xz.h" |
| |
| SRes Xz_ReadHeader(CXzStreamFlags *p, ISeqInStream *inStream) |
| { |
| Byte sig[XZ_STREAM_HEADER_SIZE]; |
| RINOK(SeqInStream_Read2(inStream, sig, XZ_STREAM_HEADER_SIZE, SZ_ERROR_NO_ARCHIVE)); |
| if (memcmp(sig, XZ_SIG, XZ_SIG_SIZE) != 0) |
| return SZ_ERROR_NO_ARCHIVE; |
| return Xz_ParseHeader(p, sig); |
| } |
| |
| #define READ_VARINT_AND_CHECK(buf, pos, size, res) \ |
| { unsigned s = Xz_ReadVarInt(buf + pos, size - pos, res); \ |
| if (s == 0) return SZ_ERROR_ARCHIVE; pos += s; } |
| |
| SRes XzBlock_ReadHeader(CXzBlock *p, ISeqInStream *inStream, Bool *isIndex, UInt32 *headerSizeRes) |
| { |
| Byte header[XZ_BLOCK_HEADER_SIZE_MAX]; |
| unsigned headerSize; |
| *headerSizeRes = 0; |
| RINOK(SeqInStream_ReadByte(inStream, &header[0])); |
| headerSize = ((unsigned)header[0] << 2) + 4; |
| if (headerSize == 0) |
| { |
| *headerSizeRes = 1; |
| *isIndex = True; |
| return SZ_OK; |
| } |
| |
| *isIndex = False; |
| *headerSizeRes = headerSize; |
| RINOK(SeqInStream_Read(inStream, header + 1, headerSize - 1)); |
| return XzBlock_Parse(p, header); |
| } |
| |
| #define ADD_SIZE_CHECH(size, val) \ |
| { UInt64 newSize = size + (val); if (newSize < size) return XZ_SIZE_OVERFLOW; size = newSize; } |
| |
| UInt64 Xz_GetUnpackSize(const CXzStream *p) |
| { |
| UInt64 size = 0; |
| size_t i; |
| for (i = 0; i < p->numBlocks; i++) |
| ADD_SIZE_CHECH(size, p->blocks[i].unpackSize); |
| return size; |
| } |
| |
| UInt64 Xz_GetPackSize(const CXzStream *p) |
| { |
| UInt64 size = 0; |
| size_t i; |
| for (i = 0; i < p->numBlocks; i++) |
| ADD_SIZE_CHECH(size, (p->blocks[i].totalSize + 3) & ~(UInt64)3); |
| return size; |
| } |
| |
| /* |
| SRes XzBlock_ReadFooter(CXzBlock *p, CXzStreamFlags f, ISeqInStream *inStream) |
| { |
| return SeqInStream_Read(inStream, p->check, XzFlags_GetCheckSize(f)); |
| } |
| */ |
| |
| static SRes Xz_ReadIndex2(CXzStream *p, const Byte *buf, size_t size, ISzAlloc *alloc) |
| { |
| size_t i, numBlocks, crcStartPos, pos = 1; |
| UInt32 crc; |
| |
| if (size < 5 || buf[0] != 0) |
| return SZ_ERROR_ARCHIVE; |
| |
| size -= 4; |
| crc = CrcCalc(buf, size); |
| if (crc != GetUi32(buf + size)) |
| return SZ_ERROR_ARCHIVE; |
| |
| { |
| UInt64 numBlocks64; |
| READ_VARINT_AND_CHECK(buf, pos, size, &numBlocks64); |
| numBlocks = (size_t)numBlocks64; |
| if (numBlocks != numBlocks64 || numBlocks * 2 > size) |
| return SZ_ERROR_ARCHIVE; |
| } |
| |
| crcStartPos = pos; |
| Xz_Free(p, alloc); |
| if (numBlocks != 0) |
| { |
| p->numBlocks = numBlocks; |
| p->numBlocksAllocated = numBlocks; |
| p->blocks = alloc->Alloc(alloc, sizeof(CXzBlockSizes) * numBlocks); |
| if (p->blocks == 0) |
| return SZ_ERROR_MEM; |
| for (i = 0; i < numBlocks; i++) |
| { |
| CXzBlockSizes *block = &p->blocks[i]; |
| READ_VARINT_AND_CHECK(buf, pos, size, &block->totalSize); |
| READ_VARINT_AND_CHECK(buf, pos, size, &block->unpackSize); |
| if (block->totalSize == 0) |
| return SZ_ERROR_ARCHIVE; |
| } |
| } |
| while ((pos & 3) != 0) |
| if (buf[pos++] != 0) |
| return SZ_ERROR_ARCHIVE; |
| return (pos == size) ? SZ_OK : SZ_ERROR_ARCHIVE; |
| } |
| |
| static SRes Xz_ReadIndex(CXzStream *p, ILookInStream *stream, UInt64 indexSize, ISzAlloc *alloc) |
| { |
| SRes res; |
| size_t size; |
| Byte *buf; |
| if (indexSize > ((UInt32)1 << 31)) |
| return SZ_ERROR_UNSUPPORTED; |
| size = (size_t)indexSize; |
| if (size != indexSize) |
| return SZ_ERROR_UNSUPPORTED; |
| buf = alloc->Alloc(alloc, size); |
| if (buf == 0) |
| return SZ_ERROR_MEM; |
| res = LookInStream_Read2(stream, buf, size, SZ_ERROR_UNSUPPORTED); |
| if (res == SZ_OK) |
| res = Xz_ReadIndex2(p, buf, size, alloc); |
| alloc->Free(alloc, buf); |
| return res; |
| } |
| |
| static SRes SeekFromCur(ILookInStream *inStream, Int64 *res) |
| { |
| return inStream->Seek(inStream, res, SZ_SEEK_CUR); |
| } |
| |
| static SRes Xz_ReadBackward(CXzStream *p, ILookInStream *stream, Int64 *startOffset, ISzAlloc *alloc) |
| { |
| UInt64 indexSize; |
| Byte buf[XZ_STREAM_FOOTER_SIZE]; |
| |
| if ((*startOffset & 3) != 0 || *startOffset < XZ_STREAM_FOOTER_SIZE) |
| return SZ_ERROR_NO_ARCHIVE; |
| *startOffset = -XZ_STREAM_FOOTER_SIZE; |
| RINOK(SeekFromCur(stream, startOffset)); |
| |
| RINOK(LookInStream_Read2(stream, buf, XZ_STREAM_FOOTER_SIZE, SZ_ERROR_NO_ARCHIVE)); |
| |
| if (memcmp(buf + 10, XZ_FOOTER_SIG, XZ_FOOTER_SIG_SIZE) != 0) |
| { |
| Int64 i = 0; |
| *startOffset += XZ_STREAM_FOOTER_SIZE; |
| for (;;) |
| { |
| int j; |
| size_t processedSize; |
| #define TEMP_BUF_SIZE (1 << 10) |
| Byte tempBuf[TEMP_BUF_SIZE]; |
| if (*startOffset < XZ_STREAM_FOOTER_SIZE || i > (1 << 16)) |
| return SZ_ERROR_NO_ARCHIVE; |
| processedSize = (*startOffset > TEMP_BUF_SIZE) ? TEMP_BUF_SIZE : (size_t)*startOffset; |
| i += processedSize; |
| *startOffset = -(Int64)processedSize; |
| RINOK(SeekFromCur(stream, startOffset)); |
| RINOK(LookInStream_Read2(stream, tempBuf, processedSize, SZ_ERROR_NO_ARCHIVE)); |
| for (j = (int)processedSize; j >= 1; j--) // FIXED j >= 0 => j >= 1 |
| if (tempBuf[j -1] != 0) |
| break; |
| if (j != 0) |
| { |
| if ((j & 3) != 0) |
| return SZ_ERROR_NO_ARCHIVE; |
| *startOffset += j; |
| if (*startOffset < XZ_STREAM_FOOTER_SIZE) |
| return SZ_ERROR_NO_ARCHIVE; |
| *startOffset -= XZ_STREAM_FOOTER_SIZE; |
| RINOK(stream->Seek(stream, startOffset, SZ_SEEK_SET)); |
| RINOK(LookInStream_Read2(stream, buf, XZ_STREAM_FOOTER_SIZE, SZ_ERROR_NO_ARCHIVE)); |
| if (memcmp(buf + 10, XZ_FOOTER_SIG, XZ_FOOTER_SIG_SIZE) != 0) |
| return SZ_ERROR_NO_ARCHIVE; |
| break; |
| } |
| } |
| } |
| |
| p->flags = (CXzStreamFlags)GetBe16(buf + 8); |
| |
| if (!XzFlags_IsSupported(p->flags)) |
| return SZ_ERROR_UNSUPPORTED; |
| |
| if (GetUi32(buf) != CrcCalc(buf + 4, 6)) |
| return SZ_ERROR_ARCHIVE; |
| |
| indexSize = ((UInt64)GetUi32(buf + 4) + 1) << 2; |
| |
| *startOffset = -(Int64)(indexSize + XZ_STREAM_FOOTER_SIZE); |
| RINOK(SeekFromCur(stream, startOffset)); |
| |
| RINOK(Xz_ReadIndex(p, stream, indexSize, alloc)); |
| |
| { |
| UInt64 totalSize = Xz_GetPackSize(p); |
| UInt64 sum = XZ_STREAM_HEADER_SIZE + totalSize + indexSize; |
| if (totalSize == XZ_SIZE_OVERFLOW || |
| sum >= ((UInt64)1 << 63) || |
| totalSize >= ((UInt64)1 << 63)) |
| return SZ_ERROR_ARCHIVE; |
| *startOffset = -(Int64)sum; |
| RINOK(SeekFromCur(stream, startOffset)); |
| } |
| { |
| CXzStreamFlags headerFlags; |
| CSecToRead secToRead; |
| SecToRead_CreateVTable(&secToRead); |
| secToRead.realStream = stream; |
| |
| RINOK(Xz_ReadHeader(&headerFlags, &secToRead.s)); |
| return (p->flags == headerFlags) ? SZ_OK : SZ_ERROR_ARCHIVE; |
| } |
| } |
| |
| |
| /* ---------- Xz Streams ---------- */ |
| |
| void Xzs_Construct(CXzs *p) |
| { |
| p->num = p->numAllocated = 0; |
| p->streams = 0; |
| } |
| |
| void Xzs_Free(CXzs *p, ISzAlloc *alloc) |
| { |
| size_t i; |
| for (i = 0; i < p->num; i++) |
| Xz_Free(&p->streams[i], alloc); |
| alloc->Free(alloc, p->streams); |
| p->num = p->numAllocated = 0; |
| p->streams = 0; |
| } |
| |
| UInt64 Xzs_GetNumBlocks(const CXzs *p) |
| { |
| UInt64 num = 0; |
| size_t i; |
| for (i = 0; i < p->num; i++) |
| num += p->streams[i].numBlocks; |
| return num; |
| } |
| |
| UInt64 Xzs_GetUnpackSize(const CXzs *p) |
| { |
| UInt64 size = 0; |
| size_t i; |
| for (i = 0; i < p->num; i++) |
| ADD_SIZE_CHECH(size, Xz_GetUnpackSize(&p->streams[i])); |
| return size; |
| } |
| |
| /* |
| UInt64 Xzs_GetPackSize(const CXzs *p) |
| { |
| UInt64 size = 0; |
| size_t i; |
| for (i = 0; i < p->num; i++) |
| ADD_SIZE_CHECH(size, Xz_GetTotalSize(&p->streams[i])); |
| return size; |
| } |
| */ |
| |
| SRes Xzs_ReadBackward(CXzs *p, ILookInStream *stream, Int64 *startOffset, ICompressProgress *progress, ISzAlloc *alloc) |
| { |
| Int64 endOffset = 0; |
| RINOK(stream->Seek(stream, &endOffset, SZ_SEEK_END)); |
| *startOffset = endOffset; |
| for (;;) |
| { |
| CXzStream st; |
| SRes res; |
| Xz_Construct(&st); |
| res = Xz_ReadBackward(&st, stream, startOffset, alloc); |
| st.startOffset = *startOffset; |
| RINOK(res); |
| if (p->num == p->numAllocated) |
| { |
| size_t newNum = p->num + p->num / 4 + 1; |
| Byte *data = (Byte *)alloc->Alloc(alloc, newNum * sizeof(CXzStream)); |
| if (data == 0) |
| return SZ_ERROR_MEM; |
| p->numAllocated = newNum; |
| memcpy(data, p->streams, p->num * sizeof(CXzStream)); |
| alloc->Free(alloc, p->streams); |
| p->streams = (CXzStream *)data; |
| } |
| p->streams[p->num++] = st; |
| if (*startOffset == 0) |
| break; |
| RINOK(stream->Seek(stream, startOffset, SZ_SEEK_SET)); |
| if (progress && progress->Progress(progress, endOffset - *startOffset, (UInt64)(Int64)-1) != SZ_OK) |
| return SZ_ERROR_PROGRESS; |
| } |
| return SZ_OK; |
| } |