Merge pull request #461 from negativeExponent/libchdr

[pcsx_rearmed.git] / deps / lzma-16.04 / C / Xz.c

/* Xz.c - Xz\r
2015-05-01 : Igor Pavlov : Public domain */\r
\r
#include "Precomp.h"\r
\r
#include "7zCrc.h"\r
#include "CpuArch.h"\r
#include "Xz.h"\r
#include "XzCrc64.h"\r
\r
const Byte XZ_SIG[XZ_SIG_SIZE] = { 0xFD, '7', 'z', 'X', 'Z', 0 };\r
const Byte XZ_FOOTER_SIG[XZ_FOOTER_SIG_SIZE] = { 'Y', 'Z' };\r
\r
unsigned Xz_WriteVarInt(Byte *buf, UInt64 v)\r
{\r
  unsigned i = 0;\r
  do\r
  {\r
    buf[i++] = (Byte)((v & 0x7F) | 0x80);\r
    v >>= 7;\r
  }\r
  while (v != 0);\r
  buf[i - 1] &= 0x7F;\r
  return i;\r
}\r
\r
void Xz_Construct(CXzStream *p)\r
{\r
  p->numBlocks = p->numBlocksAllocated = 0;\r
  p->blocks = 0;\r
  p->flags = 0;\r
}\r
\r
void Xz_Free(CXzStream *p, ISzAlloc *alloc)\r
{\r
  alloc->Free(alloc, p->blocks);\r
  p->numBlocks = p->numBlocksAllocated = 0;\r
  p->blocks = 0;\r
}\r
\r
unsigned XzFlags_GetCheckSize(CXzStreamFlags f)\r
{\r
  unsigned t = XzFlags_GetCheckType(f);\r
  return (t == 0) ? 0 : (4 << ((t - 1) / 3));\r
}\r
\r
void XzCheck_Init(CXzCheck *p, unsigned mode)\r
{\r
  p->mode = mode;\r
  switch (mode)\r
  {\r
    case XZ_CHECK_CRC32: p->crc = CRC_INIT_VAL; break;\r
    case XZ_CHECK_CRC64: p->crc64 = CRC64_INIT_VAL; break;\r
    case XZ_CHECK_SHA256: Sha256_Init(&p->sha); break;\r
  }\r
}\r
\r
void XzCheck_Update(CXzCheck *p, const void *data, size_t size)\r
{\r
  switch (p->mode)\r
  {\r
    case XZ_CHECK_CRC32: p->crc = CrcUpdate(p->crc, data, size); break;\r
    case XZ_CHECK_CRC64: p->crc64 = Crc64Update(p->crc64, data, size); break;\r
    case XZ_CHECK_SHA256: Sha256_Update(&p->sha, (const Byte *)data, size); break;\r
  }\r
}\r
\r
int XzCheck_Final(CXzCheck *p, Byte *digest)\r
{\r
  switch (p->mode)\r
  {\r
    case XZ_CHECK_CRC32:\r
      SetUi32(digest, CRC_GET_DIGEST(p->crc));\r
      break;\r
    case XZ_CHECK_CRC64:\r
    {\r
      int i;\r
      UInt64 v = CRC64_GET_DIGEST(p->crc64);\r
      for (i = 0; i < 8; i++, v >>= 8)\r
        digest[i] = (Byte)(v & 0xFF);\r
      break;\r
    }\r
    case XZ_CHECK_SHA256:\r
      Sha256_Final(&p->sha, digest);\r
      break;\r
    default:\r
      return 0;\r
  }\r
  return 1;\r
}\r