The code makes a lot of assumption but they are explicitly stated. It may work under some strictly defined conditions but after several months you or anyone else modifying may forget what those conditions were and it would lead to a memory corrupting bug which would be very hard to trace.
Tom Abracode
On Jan 10, 2005, at 2:39 PM, [EMAIL PROTECTED] wrote:
Windows XP, visual studio .NET. The malloc call ends up calling RtlAllocateHeap().
I hacked the code to allocate the aType structure from a circular ring
buffer. This small change made my app go from spending 60% of its time in
malloc to about 3%.
Here's the allocator I hacked in. No freeing is needed, the buffer just wraps. This assumes that by the time a wrap occurs, memory perviously allocated at the top is no longer needed. It seems to work ok from my limited testing. :-)
#define SQLITE_WORK_BUFF_SIZE (128*1024) // make power of 2 #define SQLITE_WORK_BUFF_MASK (SQLITE_WORK_BUFF_SIZE-1) char sqlite_workBuff[SQLITE_WORK_BUFF_SIZE]; int sqlite_writeIdx=0;
void *SQLITE_ALLOC(int nBytes)
{
void *ret;
sqlite_writeIdx = (sqlite_writeIdx + nBytes) & SQLITE_WORK_BUFF_MASK;
ret = sqlite_workBuff + sqlite_writeIdx;
sqlite_writeIdx+=nBytes;
return ret;
}
Matthew Arrington Sony Computer Entertainment America
