char*
CoinMempool::alloc()
{
lock_mutex();
if (first_free_ == NULL) {
unlock_mutex();
char* block = allocate_new_block();
lock_mutex();
#if (COIN_MEMPOOL_SAVE_BLOCKHEADS==1)
// see if we can record another block head. If not, then resize
// block_heads
if (max_block_num_ == block_num_) {
max_block_num_ = 2 * block_num_ + 10;
char** old_block_heads = block_heads_;
block_heads_ = (char**)malloc(max_block_num_ * sizeof(char*));
CoinMemcpyN( old_block_heads,block_num_,block_heads_);
free(old_block_heads);
}
// save the new block
block_heads_[block_num_++] = block;
#endif
// link in the new block
*(char**)(block+((last_block_size_-1)*entry_size_)) = first_free_;
first_free_ = block;
}
char* p = first_free_;
first_free_ = *(char**)p;
unlock_mutex();
return p;
}
Block* get_block(uint32_t chunk_size)
{
const int index = GET_POOL_INDEX(chunk_size);
assert(index >= 0 && index < sizeof(block_pools)/sizeof(*block_pools));
if(block_pools[index]) {
return block_pools[index];
}
// free memory from other threads and then try again. This requires a mutex
// lock, but this code should be rarely reached.
collect_memory_from_other_threads();
if(block_pools[index]) {
return block_pools[index];
}
Block* block = allocate_new_block(chunk_size);
if(block == NULL) {
return block;
}
add_block_to_pool(block);
return block;
}
