Obtain function args from callstack address

Question

I am printing out some debug information about the callstack. I can get the function name easily enough using SymFromAddr

void getFunctionInfo(FunctionInfo& funcInfo, uintptr_t address)
{
   DWORD64 dwDisplacement; //not used

   static char buffer[ sizeof(SYMBOL_INFO) + MAX_SYM_NAME ];
   PSYMBOL_INFO pSymbol = (PSYMBOL_INFO) buffer;

   pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
   pSymbol->MaxNameLen = MAX_SYM_NAME;

   if ( SymFromAddr( m_process, address, &dwDisplacement, pSymbol) )
   {
    strcpy(funcInfo.funcName, pSymbol->Name, MAX_SYM_NAME);     
   }

   //TODO get function arguments 

}

However I want to reproduce the full signature of the function in order to disambiguate between overrides and basically reproduce what is shown in the visual studio callstack window. I am unable to find an api call to achieve this.

Is there one?

Answer 1

Thanks to @IInspectable for providing me with the answer: UnDecorateSymbolName

This is my modified code:

void getFunctionInfo(FunctionInfo& funcInfo, uintptr_t address)
{

    static char buffer[ sizeof(SYMBOL_INFO) + MAX_SYM_NAME ];
    PSYMBOL_INFO pSymbol = (PSYMBOL_INFO) buffer;

    pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
    pSymbol->MaxNameLen = MAX_SYM_NAME;

   //set sym options to get the mangled function name 

    DWORD64 dwDisplacement;
    DWORD options = SymGetOptions();
    DWORD newOptions = options & ~SYMOPT_UNDNAME;
    newOptions = newOptions | SYMOPT_PUBLICS_ONLY;
    SymSetOptions(newOptions);

    if (SymFromAddr(m_process, address, &dwDisplacement, pSymbol))  //m_process is set up elsewhere
    {
       //convert to full function name complete with params      
       char undecoratedName[MAX_SYM_NAME];
       UnDecorateSymbolName(pSymbol->Name, undecoratedName, MAX_SYM_NAME, UNDNAME_COMPLETE);

       strncpy(funcInfo.funcName, undecoratedName, MAX_SYM_NAME);
    }

    //revert to original options
    SymSetOptions(options);   
}

There is also a more complicated but more powerful way of getting function parameters and more besides by using SymGetTypeInfo. Details of this can be found at this excellent CodeProject article: Using PDB files and symbols to debug your application