inline void *place(void *bp, size_t aSize) //alloc!
{
#ifdef __DEBUG__
printf("placing on %u, size %u\n",getBlockHeader(bp), aSize);
#endif
erase(getSize(getBlockHeader(bp)), bp); //no empty
size_t cSize = getSize(getBlockHeader(bp));
if((cSize - aSize) >= 2*DSIZE)
{
if(aSize>=100) { //huge block to right
set(getBlockHeader(bp), setMask(cSize - aSize, 0));
set(getBlockFooter(bp), setMask(cSize - aSize, 0));
bp = getNextBlock(bp);
set(getBlockHeader(bp), setMask(aSize, 1));
set(getBlockFooter(bp), setMask(aSize, 1));
push_back(cSize-aSize, getPrevBlock(bp));
return bp;
} else { //tiny block to left
set(getBlockHeader(bp), setMask(aSize, 1));
set(getBlockFooter(bp), setMask(aSize, 1));
bp = getNextBlock(bp);
set(getBlockHeader(bp), setMask(cSize - aSize, 0));
set(getBlockFooter(bp), setMask(cSize - aSize, 0));
push_back(cSize-aSize, bp);
return getPrevBlock(bp);
}
}
else
{
set(getBlockHeader(bp), setMask(cSize, 1));
set(getBlockFooter(bp), setMask(cSize, 1));
}
return bp;
}
static void *coalesce(void *bp)
{
unsigned int prev_allocfield = getAlloc(getBlockFooter(getPrevBlock(bp)));
unsigned int next_allocfield = getAlloc(getBlockHeader(getNextBlock(bp)));
unsigned int size = getSize(getBlockHeader(bp));
if(prev_allocfield && next_allocfield)
return bp;
if(prev_allocfield && !next_allocfield)
{
size += getSize(getBlockHeader(getNextBlock(bp)));
put(getBlockHeader(bp),pack(size,0));
put(getBlockFooter(bp),pack(size,0));
}
else if(!prev_allocfield && next_allocfield)
{
size += getSize(getBlockHeader(getPrevBlock(bp)));
put(getBlockHeader(getPrevBlock(bp)),pack(size,0));
put(getBlockFooter(bp),pack(size,0));
}
else
{
size += getSize(getBlockHeader(getPrevBlock(bp))) + getSize(getBlockHeader(getNextBlock(bp)));
put(getBlockHeader(getPrevBlock(bp)),pack(size,0));
put(getBlockFooter(getNextBlock(bp)),pack(size,0));
bp = getPrevBlock(bp);
}
return bp;
}
static void *coalesce(void *bp)
{
#ifdef __DEBUG__
fprintf(stderr, "Coalescing...\n");
#endif
size_t p = isAllocated(getBlockHeader(getPrevBlock(bp))); //allocated "physically" previous block?
size_t n = isAllocated(getBlockHeader(getNextBlock(bp))); //allocated "physicall" next block?
size_t size = getSize(getBlockHeader(bp)); //get block size
if(p && n) { //no coalescing
return bp;
}
else if(!p && n) //previous block is empty!
{
#ifdef __DEBUG__
fprintf(stderr, "Merging %u(size : %u) and %u(size : %u)...\n", getPrevBlock(bp), getSize(getBlockHeader(getPrevBlock(bp))), bp, getSize(getBlockHeader(bp)));
#endif
erase(size, bp); //delete current block
erase(getSize(getBlockHeader(getPrevBlock(bp))), getPrevBlock(bp)); //delete previous block
size += getSize(getBlockHeader(getPrevBlock(bp)));
set(getBlockFooter(bp), setMask(size, 0));
set(getBlockHeader(getPrevBlock(bp)), setMask(size, 0));
push_back(size, getPrevBlock(bp)); //add summed block
return getPrevBlock(bp);
}
else if(p && !n) //next block is empty!
{
#ifdef __DEBUG__
fprintf(stderr, "Merging %u(size : %u) and %u(size : %u)...\n", bp, getSize(getBlockHeader(bp)), getNextBlock(bp), getSize(getBlockHeader(getNextBlock(bp))));
#endif
erase(size, bp); //delete current
erase(getSize(getBlockHeader(getNextBlock(bp))), getNextBlock(bp)); //delete next
size += getSize(getBlockHeader(getNextBlock(bp)));
set(getBlockHeader(bp), setMask(size, 0));
set(getBlockFooter(bp), setMask(size, 0));
push_back(size, bp); //add summed block
return bp;
}
else //both block are empty!
{
#ifdef __DEBUG__
fprintf(stderr, "Merging %u(size : %u), %u(size : %u) and %u(size : %u)...\n", getPrevBlock(bp), getSize(getBlockHeader(getPrevBlock(bp))), bp, getSize(getBlockHeader(bp)), getNextBlock(bp), getSize(getBlockHeader(getNextBlock(bp))));
#endif
erase(size, bp); //delete every adjacent block
erase(getSize(getBlockHeader(getPrevBlock(bp))), getPrevBlock(bp));
erase(getSize(getBlockHeader(getNextBlock(bp))), getNextBlock(bp));
size += getSize(getBlockHeader(getNextBlock(bp))) + getSize(getBlockHeader(getPrevBlock(bp)));
set(getBlockHeader(getPrevBlock(bp)), setMask(size, 0));
set(getBlockFooter(getNextBlock(bp)), setMask(size, 0));
push_back(size, getPrevBlock(bp)); //sum up
return getPrevBlock(bp);
}
}
