Hey all, I'm got some decently complex code here, using a dll to set up a global mouse hook(windows stuff). Anyway, I am getting this error:
C:/Users/JohnJr/Desktop/My Programs/Hooks/Test/main.cpp
.text$_ZN9MouseHook11SetFunctionEPc[MouseHook::SetFunction(char*)]+0x55): undefined reference to `__imp__MProc@12'
I'm not quite sure why it isn't recognizing the MProc. Here's my code, and I have linked the .a file to my project.
Program main.cpp
Code:
#include <windows.h>
#include <iostream>
#include "C:\Users\JohnJr\Desktop\My Programs\Hooks\MouseHook.h"
#include "C:\Users\JohnJr\Desktop\My Programs\Hooks\HookProcs\main.h"
/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);
/* Make the class name into a global variable */
char szClassName[ ] = "CodeBlocksWindowsApp";
extern int mouseX;
extern int mouseY;
MouseHook* h = 0;
int WINAPI WinMain (HINSTANCE hThisInstance,
HINSTANCE hPrevInstance,
LPSTR lpszArgument,
int nCmdShow)
{
HWND hwnd; /* This is the handle for our window */
MSG messages; /* Here messages to the application are saved */
WNDCLASSEX wincl; /* Data structure for the windowclass */
/* The Window structure */
wincl.hInstance = hThisInstance;
wincl.lpszClassName = szClassName;
wincl.lpfnWndProc = WindowProcedure; /* This function is called by windows */
wincl.style = CS_DBLCLKS; /* Catch double-clicks */
wincl.cbSize = sizeof (WNDCLASSEX);
/* Use default icon and mouse-pointer */
wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
wincl.lpszMenuName = NULL; /* No menu */
wincl.cbClsExtra = 0; /* No extra bytes after the window class */
wincl.cbWndExtra = 0; /* structure or the window instance */
/* Use Windows's default colour as the background of the window */
wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;
/* Register the window class, and if it fails quit the program */
if (!RegisterClassEx (&wincl))
return 0;
/* The class is registered, let's create the program*/
hwnd = CreateWindowEx (
0, /* Extended possibilites for variation */
szClassName, /* Classname */
"Code::Blocks Template Windows App", /* Title Text */
WS_OVERLAPPEDWINDOW, /* default window */
CW_USEDEFAULT, /* Windows decides the position */
CW_USEDEFAULT, /* where the window ends up on the screen */
544, /* The programs width */
375, /* and height in pixels */
HWND_DESKTOP, /* The window is a child-window to desktop */
NULL, /* No menu */
hThisInstance, /* Program Instance handler */
NULL /* No Window Creation data */
);
/* Make the window visible on the screen */
ShowWindow (hwnd, nCmdShow);
h = new MouseHook();
h->SetFunction("C:/Users/JohnJr/Desktop/My Programs/Hooks/HookProcs/bin/Debug/HookProcs.dll");
/* Run the message loop. It will run until GetMessage() returns 0 */
while (GetMessage (&messages, NULL, 0, 0))
{
/* Translate virtual-key messages into character messages */
TranslateMessage(&messages);
std::cout << mouseX;
/* Send message to WindowProcedure */
DispatchMessage(&messages);
}
/* The program return-value is 0 - The value that PostQuitMessage() gave */
return messages.wParam;
}
/* This function is called by the Windows function DispatchMessage() */
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message) /* handle the messages */
{
case WM_DESTROY:
PostQuitMessage (0); /* send a WM_QUIT to the message queue */
break;
case WM_KEYUP:
if(wParam == VK_SPACE)
h->Set();
else
h->UnSet();
break;
default: /* for messages that we don't deal with */
return DefWindowProc (hwnd, message, wParam, lParam);
}
return 0;
}
MouseHook.h(The interface class)
Code:
/****************************
MouseHookClass
Author: John M
*****************************/
#ifndef MHookClass
#define MHookClass
#include <windows.h>
#include <iostream>
#include "C:\Users\JohnJr\Desktop\My Programs\Hooks\HookProcs\main.h"
class MouseHook
{
private:
LRESULT CALLBACK (*MouseProc)(int nCode, WPARAM wParam, LPARAM lParam); //MouseProc pointer
HINSTANCE hLib;
HHOOK hook; //handle to hook
public:
MouseHook()
{
hook = NULL;
hLib = NULL;
}
~MouseHook()
{
if(MouseProc != 0)
UnSet();
}
bool SetFunction(char* dll)
{
hLib=LoadLibrary(dll);
if(hLib==NULL)
{
std::cout << "Unable to load library!" << std::endl;
return false;
}
MouseProc = &MProc; << Error call is right here!
return true;
}
bool Set()
{
if(hLib == NULL)
return false;
if(hook != NULL)
return false;
hook = SetWindowsHookEx(
WH_MOUSE,
(HOOKPROC)MouseProc,
hLib,
0);
std::cout << "Hook is set";
if(hook != NULL)
return true;
return false;
}
bool UnSet()
{
if (hook == NULL)
return false;
hook = NULL;
return UnhookWindowsHookEx(hook);
}
};
#endif
The dll's main.h
Code:
#ifndef __MAIN_H__
#define __MAIN_H__
#include <windows.h>
/* To use this exported function of dll, include this header
* in your project.
*/
#ifdef BUILD_DLL
#define DLL_EXPORT __declspec(dllexport)
#else
#define DLL_EXPORT __declspec(dllimport)
#endif
#ifdef __cplusplus
extern "C"
{
#endif
DLL_EXPORT LRESULT CALLBACK MProc(int nCode, WPARAM wParam, LPARAM lParam);
int mouseX;
int mouseY;
#ifdef __cplusplus
}
#endif
#endif // __MAIN_H__
Then the main.cpp of the dll
Code:
#include "main.h"
//May need to place in shared segment
int mouseX = 0;
int mouseY = 0;
// a sample exported function
DLL_EXPORT LRESULT CALLBACK MProc(int nCode, WPARAM wParam, LPARAM lParam)
{
if(nCode < 0)
return CallNextHookEx(NULL, nCode, wParam, lParam);
//Check wParam here
if (wParam == WM_LBUTTONUP)
{
MOUSEHOOKSTRUCT * hHook = (MOUSEHOOKSTRUCT*)lParam;
mouseX = hHook->pt.x;
mouseY = hHook->pt.y;
}
return CallNextHookEx(NULL, nCode, wParam, lParam);
}
BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
{
switch (fdwReason)
{
case DLL_PROCESS_ATTACH:
// attach to process
// return FALSE to fail DLL load
break;
case DLL_PROCESS_DETACH:
// detach from process
break;
case DLL_THREAD_ATTACH:
// attach to thread
break;
case DLL_THREAD_DETACH:
// detach from thread
break;
}
return TRUE; // succesful
}
Please, if anyone can explain why the MProc isn't being recognized, I'm fairly new to DLL's and this is actually my first attempt alone. Thanks in advance!!
Solved thanks to arpsmack.. Thanks!
Originally Posted by arpsmack
