[C/C++] Inline-Assembler - API Wrapper

#include <map>
#include <vector>
using namespace std;

typedef struct {
 char * cszFilename;
 HMODULE hHandle;
} tDLL;
std::map<int, tDLL*> pDLL;

int FindFreeHandle() {
 if(pDLL.size() == 0) {
 return 0x01;
 } else {
 return (pDLL.end()->first)+1;
 }
}

unsigned int API_Wrapper LoadDLL(const char *cszFilename) {
 tDLL * pSubDLL = new tDLL;
 memset(pSubDLL,0,sizeof(tDLL));
 _cprintf("Loading Library\n");
 HMODULE hMod = LoadLibraryA((LPCSTR)cszFilename);
 int handle = FindFreeHandle();
 if(hMod) {
 pSubDLL->cszFilename = new char[strlen(cszFilename)];
 strcpy(pSubDLL->cszFilename, cszFilename);
 _cprintf("File: %s\n", pSubDLL->cszFilename);
 pSubDLL->hHandle = hMod;
 _cprintf("Handle: %u | %u\n", pSubDLL->hHandle, hMod);
 pDLL[handle] = pSubDLL;
 return handle;
 } else {
 return NULL;
 }
}

void * API_Wrapper CallDLL(unsigned int uHandle, unsigned int uCallConvention, const char *cszFunction, ...) {
 vector<void*> args;

 va_list va;
 void * aPointer;
 void * tmpEax;
 int n = 0;
 std::map<int, tDLL*>::iterator itr = pDLL.find((int)uHandle);
 if(itr != pDLL.end()) {
 HMODULE hMod = itr->second->hHandle;
 _cprintf("Calling (%s | %s): %u\n", itr->second->cszFilename, cszFunction, hMod);
 __asm {
 push cszFunction;
 push hMod;
 call dword ptr [GetProcAddress];
 cmp eax,0;
 jz func_end;
 mov tmpEax, eax
 }
 va_start(va, cszFunction);
 printf("Arglist: %p", va);
 if(va) {
 do {
 aPointer = (void*)va_arg(va, void*);
 if(aPointer) {
 args.push_back(aPointer);
 n += 4;
 }
 } while (aPointer);
 }
 va_end(va);

 for(int i = args.size(); i = 0; i = i -1) {
 if(args[i] != 0) {
 void * pArg = (void*)args[i];
 __asm {
 push pArg;
 }
 }
 }
 __asm {
 mov eax, tmpEax;
 call eax;
 }
 if(uCallConvention == 0x01) {
 if(n != 0) {
 __asm {
 add esp, n;
 }
 }
 }
 __asm {
func_end:
 retn;
 }
 } else {
 return NULL;
 }
 return NULL; //Nothing worked?
}

unsigned int CloseDLL(int uHandle) {
 std::map<int, tDLL*>::iterator itr = pDLL.find((int)uHandle);
 if(itr != pDLL.end()) {
 bool ret = FreeLibrary(itr->second->hHandle);
 pDLL.erase(itr);
 return (int)ret;
 }
 return 0;
}

push Filename;
call LoadLibraryA;
push ExportName;
push eax;
call GetProcAddress
push argument1
push argument2
call eax;
add esp,8
retn