public void AddModule(string filename, ulong baseOfDll, int sizeOfDll)
{
var baseAddress = NativeDbgHelp.SymLoadModule64(_hProcess, IntPtr.Zero, filename, null, baseOfDll, (uint)sizeOfDll);
if (baseAddress == 0)
{
// should work if the same module is added more than once
if (Marshal.GetLastWin32Error() == ERROR_SUCCESS)
{
return;
}
Console.WriteLine($"SymLoadModule64 failed for {filename}");
}
}
private bool SymInitialize(IntPtr hProcess, bool loadModules = false)
{
// read https://docs.microsoft.com/en-us/windows/win32/api/dbghelp/nf-dbghelp-symsetoptions for more details
// maybe SYMOPT_NO_PROMPTS and SYMOPT_FAIL_CRITICAL_ERRORS could be used
NativeDbgHelp.SymSetOptions(
NativeDbgHelp.SYMOPT_DEFERRED_LOADS | // performance optimization
NativeDbgHelp.SYMOPT_UNDNAME // C++ names are not mangled
);
// https://docs.microsoft.com/en-us/windows/win32/api/dbghelp/nf-dbghelp-syminitialize
// search path for symbols:
// - The current working directory of the application
// - The _NT_SYMBOL_PATH environment variable
// - The _NT_ALTERNATE_SYMBOL_PATH environment variable
//
// passing false as last parameter means that we will need to call SymLoadModule64
// each time a module is loaded in the process
return(NativeDbgHelp.SymInitialize(hProcess, null, loadModules));
}
private string GetNativeMethodName(ulong address)
{
var symbol = new NativeDbgHelp.SYMBOL_INFO();
symbol.MaxNameLen = 1024;
symbol.SizeOfStruct = (uint)Marshal.SizeOf(symbol) - 1024; // char buffer is not counted
// the ANSI version of SymFromAddr is called so each character is 1 byte long
if (NativeDbgHelp.SymFromAddr(_hProcess, address, out var displacement, ref symbol))
{
var buffer = new StringBuilder(symbol.Name.Length);
// remove weird "$##" at the end of some symbols
var pos = symbol.Name.LastIndexOf("$##");
if (pos == -1)
{
buffer.Append(symbol.Name);
}
else
{
buffer.Append(symbol.Name, 0, pos);
}
// add offset if any
if (displacement != 0)
{
buffer.Append($"+0x{displacement}");
}
return(buffer.ToString());
}
// default value is just the address in HEX
#if DEBUG
return($"0x{address:x} (SymFromAddr failed with 0x{Marshal.GetLastWin32Error():x})");
#else
return($"0x{address:x}");
#endif
}