diff options
Diffstat (limited to 'CPP/7zip/Archive/Cab/CabBlockInStream.cpp')
| -rw-r--r-- | CPP/7zip/Archive/Cab/CabBlockInStream.cpp | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/CPP/7zip/Archive/Cab/CabBlockInStream.cpp b/CPP/7zip/Archive/Cab/CabBlockInStream.cpp index 625276f3..c193434f 100644 --- a/CPP/7zip/Archive/Cab/CabBlockInStream.cpp +++ b/CPP/7zip/Archive/Cab/CabBlockInStream.cpp @@ -29,15 +29,24 @@ CCabBlockInStream::~CCabBlockInStream() static UInt32 CheckSum(const Byte *p, UInt32 size) { UInt32 sum = 0; - for (UInt32 i = size >> 2; i != 0; i--) + + for (; size >= 8; size -= 8) + { + sum ^= GetUi32(p) ^ GetUi32(p + 4); + p += 8; + } + + if (size >= 4) { sum ^= GetUi32(p); p += 4; } + size &= 3; if (size > 2) sum ^= (UInt32)(*p++) << 16; if (size > 1) sum ^= (UInt32)(*p++) << 8; if (size > 0) sum ^= (UInt32)(*p++); + return sum; } |