Programación Avanzada código dll tarea 9

#include <windows.h>
#include <malloc.h>
#include <stdio.h>
#include <tchar.h>

extern "C"
{
    typedef BOOL (WINAPI *LPFN_GLPI)(PSYSTEM_LOGICAL_PROCESSOR_INFORMATION,PDWORD);

    __declspec(dllexport) int getCoreCount(){
        LPFN_GLPI glpi;
        BOOL done = FALSE;
        PSYSTEM_LOGICAL_PROCESSOR_INFORMATION buffer = NULL;
        PSYSTEM_LOGICAL_PROCESSOR_INFORMATION ptr = NULL;
        DWORD returnLength = 0;
        DWORD processorCoreCount = 0;
        DWORD byteOffset = 0;
        HINSTANCE hDll;

        hDll=LoadLibrary("kernel32.dll");
        if (hDll==NULL) {
            printf("ERROR!!!\n");
            return(1);
        }

        glpi = (LPFN_GLPI) GetProcAddress(hDll,"GetLogicalProcessorInformation");
        if (NULL == glpi) {
            printf("\nGetLogicalProcessorInformation is not supported.\n");
            return (1);
        }

        while (!done) {
            DWORD rc = glpi(buffer, &returnLength);
            if (FALSE == rc) {
                if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
                    if (buffer)
                        free(buffer);
                    buffer = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION)malloc(
                            returnLength);
                    if (NULL == buffer) {
                        printf("\nError: Allocation failure\n");
                        return (2);
                    }
                } else {
                    printf("\nError %d\n", GetLastError());
                    return (3);
                }
            } else {
                done = TRUE;
            }
        }

        ptr = buffer;

        while (byteOffset + sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION) <= returnLength) {
            if (ptr->Relationship == RelationProcessorCore) {
                processorCoreCount++;
            }
            byteOffset += sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
            ptr++;
        }
    /*
        printf("Number of processor cores: %d\n",
                 processorCoreCount);
    */
        free(buffer);

        FreeLibrary(hDll);
        return processorCoreCount;
    }
}