| /* Xz.c - Xz |
| 2009-04-15 : Igor Pavlov : Public domain */ |
| |
| #include "7zCrc.h" |
| #include "CpuArch.h" |
| #include "Xz.h" |
| #include "XzCrc64.h" |
| |
| Byte XZ_SIG[XZ_SIG_SIZE] = { 0xFD, '7', 'z', 'X', 'Z', 0 }; |
| Byte XZ_FOOTER_SIG[XZ_FOOTER_SIG_SIZE] = { 'Y', 'Z' }; |
| |
| unsigned Xz_WriteVarInt(Byte *buf, UInt64 v) |
| { |
| unsigned i = 0; |
| do |
| { |
| buf[i++] = (Byte)((v & 0x7F) | 0x80); |
| v >>= 7; |
| } |
| while (v != 0); |
| buf[i - 1] &= 0x7F; |
| return i; |
| } |
| |
| void Xz_Construct(CXzStream *p) |
| { |
| p->numBlocks = p->numBlocksAllocated = 0; |
| p->blocks = 0; |
| p->flags = 0; |
| } |
| |
| void Xz_Free(CXzStream *p, ISzAlloc *alloc) |
| { |
| alloc->Free(alloc, p->blocks); |
| p->numBlocks = p->numBlocksAllocated = 0; |
| p->blocks = 0; |
| } |
| |
| unsigned XzFlags_GetCheckSize(CXzStreamFlags f) |
| { |
| int t = XzFlags_GetCheckType(f); |
| return (t == 0) ? 0 : (4 << ((t - 1) / 3)); |
| } |
| |
| void XzCheck_Init(CXzCheck *p, int mode) |
| { |
| p->mode = mode; |
| switch (mode) |
| { |
| case XZ_CHECK_CRC32: p->crc = CRC_INIT_VAL; break; |
| case XZ_CHECK_CRC64: p->crc64 = CRC64_INIT_VAL; break; |
| case XZ_CHECK_SHA256: Sha256_Init(&p->sha); break; |
| } |
| } |
| |
| void XzCheck_Update(CXzCheck *p, const void *data, size_t size) |
| { |
| switch (p->mode) |
| { |
| case XZ_CHECK_CRC32: p->crc = CrcUpdate(p->crc, data, size); break; |
| case XZ_CHECK_CRC64: p->crc64 = Crc64Update(p->crc64, data, size); break; |
| case XZ_CHECK_SHA256: Sha256_Update(&p->sha, (const Byte *)data, size); break; |
| } |
| } |
| |
| int XzCheck_Final(CXzCheck *p, Byte *digest) |
| { |
| switch (p->mode) |
| { |
| case XZ_CHECK_CRC32: |
| SetUi32(digest, CRC_GET_DIGEST(p->crc)); |
| break; |
| case XZ_CHECK_CRC64: |
| { |
| int i; |
| UInt64 v = CRC64_GET_DIGEST(p->crc64); |
| for (i = 0; i < 8; i++, v >>= 8) |
| digest[i] = (Byte)(v & 0xFF); |
| break; |
| } |
| case XZ_CHECK_SHA256: |
| Sha256_Final(&p->sha, digest); |
| break; |
| default: |
| return 0; |
| } |
| return 1; |
| } |