nsSegmentedBuffer.h revision 677833bc953b6cb418c701facbdcf4aa18d6c44e
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#ifndef nsSegmentedBuffer_h__
#define nsSegmentedBuffer_h__
#include "nsMemory.h"
#include "prclist.h"
{
: mSegmentSize(0), mMaxSize(0),
mFirstSegmentIndex(0), mLastSegmentIndex(0) {}
~nsSegmentedBuffer() {
Empty();
}
// returns true if no more segments remain:
// returns true if no more segments remain:
// Call Realloc() on last segment. This is used to reduce memory
// consumption when data is not an exact multiple of segment size.
inline PRUint32 GetSegmentCount() {
if (mFirstSegmentIndex <= mLastSegmentIndex)
return mLastSegmentIndex - mFirstSegmentIndex;
else
}
return mSegmentArray[i];
}
"non-power-of-2 mSegmentArrayCount");
return result;
}
}
char** mSegmentArray;
};
// NS_SEGMENTARRAY_INITIAL_SIZE: This number needs to start out as a
// power of 2 given how it gets used. We double the segment array
// when we overflow it, and use that fact that it's a power of 2
// to compute a fast modulus operation in IsFull.
//
// 32 segment array entries can accommodate 128k of data if segments
// are 4k in size. That seems like a reasonable amount that will avoid
// needing to grow the segment array.
#define NS_SEGMENTARRAY_INITIAL_COUNT 32
#endif // nsSegmentedBuffer_h__