thirdparty/scummvm
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COMMON: Fix potential UB while shifting Common::BitStream

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Shifting a 32-bit value by more than 31 is undefined.
This commit is contained in:
Sven Hesse 2011-10-20 20:47:53 +02:00
parent eb8aee1335
commit 657ee2da59
1 changed files with 6 additions and 0 deletions
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6
common/bitstream.h
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@ -176,6 +176,9 @@ public:
/** Read a multi-bit value from the bit stream. */
uint32 getBits(uint8 n) {
if (n == 0)
return 0;
if (n > 32)
error("BitStreamImpl::getBits(): Too many bits requested to be read");
@ -225,6 +228,9 @@ public:
/** Add a bit to the value x, making it an n-bit value. */
void addBit(uint32 &x, uint32 n) {
if (n >= 32)
error("BitStreamImpl::addBit(): Too many bits requested to be read");
if (isMSB2LSB)
x = (x << 1) | getBit();
else