Thread: Getting heap allocations

Depends how you're counting the bytes. If you're just counting the dwCommittedSize of the HEAP_REGION blocks you'll miss the big blocks since they are counted as seperate regions but not tagged as such (it's described in the PROCESS_HEAP_ENTRY::iRegionIndex docs). Summing up the cbData member of all PROCESS_HEAP_ENTRY_BUSY blocks will get you an accurate committed byte count.

Maybe this'll help:

Code:

void DisplayHeapsInfo(std::ostream& out = std::cout)
{
    std::vector<HANDLE> heaps(GetProcessHeaps(0, NULL));
    GetProcessHeaps(heaps.size(), &heaps[0]);
    DWORD totalBytes = 0;
    for(DWORD i = 0; i < heaps.size(); ++i)
    {
        out << "Heap handle: 0x" << heaps[i] << '\n';
        PROCESS_HEAP_ENTRY phi = {0};
        while(HeapWalk(heaps[i], &phi))
        {
            out << "Block Start Address: 0x" << phi.lpData << '\n';
            out << "\tSize: " << phi.cbData << " - Overhead: "
                           << static_cast<DWORD>(phi.cbOverhead) << '\n';
            out << "\tBlock is a";
            if(phi.wFlags & PROCESS_HEAP_REGION)
            {
                out << " VMem region:\n";
                out << "\tCommitted size: " << phi.Region.dwCommittedSize << '\n';
                out << "\tUncomitted size: " << phi.Region.dwUnCommittedSize << '\n';
                out << "\tFirst block: 0x" << phi.Region.lpFirstBlock << '\n';
                out << "\tLast block: 0x" << phi.Region.lpLastBlock << '\n';
            }
            else 
            {
                if(phi.wFlags & PROCESS_HEAP_UNCOMMITTED_RANGE)
                {
                    out << "n uncommitted range\n";
                }
                else if(phi.wFlags & PROCESS_HEAP_ENTRY_BUSY)
                {
                    totalBytes += phi.cbData;
                    out << "n Allocated range: Region index - " 
                                   << static_cast<unsigned>(phi.iRegionIndex) << '\n';
                    if(phi.wFlags & PROCESS_HEAP_ENTRY_MOVEABLE)
                    {
                        out << "\tMovable: Handle is 0x" << phi.Block.hMem << '\n';
                    }
                    else if(phi.wFlags & PROCESS_HEAP_ENTRY_DDESHARE)
                    {
                        out << "\tDDE Sharable\n";
                    }
                }
                else out << " block, no other flags specified\n";
            }
            out << std::endl;
        }
    }
    out << "End of report - total of " << std::dec << totalBytes << " allocated" << std::endl;
}