reactos/lib/sdk/scrnsave/scrnsave.c

   1 /*
   2  * PROJECT:         ReactOS Screen Saver Library
   3  * LICENSE:         GPL v2 or any later version
   4  * FILE:            lib/sdk/scrnsave/scrnsave.c
   5  * PURPOSE:         Library for writing screen savers, compatible with MS' scrnsave.lib
   6  * PROGRAMMERS:     Anders Norlander <anorland@hem2.passagen.se>
   7  *                  Colin Finck <mail@colinfinck.de>
   8  */
   9
  10 #include <stdarg.h>
  11 #include <windef.h>
  12 #include <winbase.h>
  13 #include <wingdi.h>
  14 #include <winuser.h>
  15 #include <tchar.h>
  16 #include <scrnsave.h>
  17
  18 // Screen Saver window class
  19 #define CLASS_SCRNSAVE TEXT("WindowsScreenSaverClass")
  20
  21 // Globals
  22 HWND        hMainWindow = NULL;
  23 BOOL        fChildPreview = FALSE;
  24 HINSTANCE   hMainInstance;
  25 TCHAR       szName[TITLEBARNAMELEN];
  26 TCHAR       szAppName[APPNAMEBUFFERLEN];
  27 TCHAR       szIniFile[MAXFILELEN];
  28 TCHAR       szScreenSaver[22];
  29 TCHAR       szHelpFile[MAXFILELEN];
  30 TCHAR       szNoHelpMemory[BUFFLEN];
  31 UINT        MyHelpMessage;
  32
  33 // Local house keeping
  34 static POINT pt_orig;
  35
  36 static int ISSPACE(TCHAR c)
  37 {
  38     return (c == ' ' || c == '\t');
  39 }
  40
  41 #define ISNUM(c) ((c) >= '0' && c <= '9')
  42
  43 static ULONG_PTR _toulptr(const TCHAR *s)
  44 {
  45     ULONG_PTR res;
  46     ULONG_PTR n;
  47     const TCHAR *p;
  48
  49     for (p = s; *p; p++)
  50         if (!ISNUM(*p))
  51             break;
  52
  53     p--;
  54     res = 0;
  55
  56     for (n = 1; p >= s; p--, n *= 10)
  57         res += (*p - '0') * n;
  58
  59     return res;
  60 }
  61
  62 // This function takes care of *must* do tasks, like terminating screen saver
  63 static LRESULT WINAPI SysScreenSaverProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
  64 {
  65     switch(uMsg)
  66     {
  67         case WM_CREATE:
  68             // Mouse is not supposed to move from this position
  69             GetCursorPos(&pt_orig);
  70             break;
  71
  72         case WM_DESTROY:
  73             PostQuitMessage(0);
  74             break;
  75
  76         case WM_SYSCOMMAND:
  77             if (!fChildPreview)
  78             {
  79                 switch (wParam)
  80                 {
  81                     case SC_CLOSE:
  82                     case SC_SCREENSAVE:
  83                         return FALSE;
  84                 }
  85             }
  86             break;
  87     }
  88
  89     return ScreenSaverProc(hWnd, uMsg, wParam, lParam);
  90 }
  91
  92 LRESULT WINAPI DefScreenSaverProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
  93 {
  94     // Don't do any special processing when in preview mode
  95     if (fChildPreview)
  96         return DefWindowProc(hWnd, uMsg, wParam, lParam);
  97
  98     switch (uMsg)
  99     {
 100         case WM_NCACTIVATE:
 101         case WM_ACTIVATE:
 102         case WM_ACTIVATEAPP:
 103             if (!wParam)
 104             {
 105                 // wParam is FALSE, so the screensaver is losing the focus.
 106                 PostMessage(hWnd, WM_CLOSE, 0, 0);
 107             }
 108             break;
 109
 110         case WM_MOUSEMOVE:
 111         {
 112             POINT pt;
 113             GetCursorPos(&pt);
 114             if (pt.x == pt_orig.x && pt.y == pt_orig.y)
 115                 break;
 116
 117             // Fall through
 118         }
 119
 120         case WM_LBUTTONDOWN:
 121         case WM_RBUTTONDOWN:
 122         case WM_MBUTTONDOWN:
 123         case WM_KEYDOWN:
 124         case WM_KEYUP:
 125             // Send a WM_CLOSE to close the screen saver (allows the screensaver author to do clean-up tasks)
 126             PostMessage(hWnd, WM_CLOSE, 0, 0);
 127             break;
 128
 129         case WM_SETCURSOR:
 130             SetCursor(NULL);
 131             return TRUE;
 132     }
 133
 134     return DefWindowProc(hWnd, uMsg, wParam, lParam);
 135 }
 136
 137 // Registers the screen saver window class
 138 static BOOL RegisterScreenSaverClass(void)
 139 {
 140     WNDCLASS cls = {0,};
 141
 142     cls.hIcon = LoadIcon(hMainInstance, MAKEINTATOM(ID_APP));
 143     cls.lpszClassName = CLASS_SCRNSAVE;
 144     cls.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
 145     cls.hInstance = hMainInstance;
 146     cls.style = CS_VREDRAW | CS_HREDRAW | CS_SAVEBITS | CS_PARENTDC;
 147     cls.lpfnWndProc = (WNDPROC)SysScreenSaverProc;
 148
 149     return RegisterClass(&cls) != 0;
 150 }
 151
 152 static void LaunchConfig(void)
 153 {
 154     // Only show the dialog if the RegisterDialogClasses function succeeded.
 155     // This is the same behaviour as MS' scrnsave.lib.
 156     if( RegisterDialogClasses(hMainInstance) )
 157         DialogBox(hMainInstance, MAKEINTRESOURCE(DLG_SCRNSAVECONFIGURE), GetForegroundWindow(), (DLGPROC) ScreenSaverConfigureDialog);
 158 }
 159
 160 static int LaunchScreenSaver(HWND hParent)
 161 {
 162     UINT style;
 163     RECT rc;
 164     MSG msg;
 165
 166     if (!RegisterScreenSaverClass())
 167     {
 168         MessageBox(NULL, TEXT("RegisterClass() failed"), NULL, MB_ICONHAND);
 169         return 1;
 170     }
 171
 172     // A slightly different approach needs to be used when displaying in a preview window
 173     if (hParent)
 174     {
 175         style = WS_CHILD;
 176         GetClientRect(hParent, &rc);
 177     }
 178     else
 179     {
 180         style = WS_POPUP;
 181         rc.right = GetSystemMetrics(SM_CXVIRTUALSCREEN);
 182         rc.bottom = GetSystemMetrics(SM_CYVIRTUALSCREEN);
 183         style |= WS_VISIBLE;
 184     }
 185
 186     // Create the main screen saver window
 187     hMainWindow = CreateWindowEx(hParent ? 0 : WS_EX_TOPMOST, CLASS_SCRNSAVE,
 188                                  TEXT("SCREENSAVER"), style,
 189                                  0, 0, rc.right, rc.bottom, hParent, NULL,
 190                                  hMainInstance, NULL);
 191
 192     if(!hMainWindow)
 193         return 1;
 194
 195     // Display window and start pumping messages
 196     ShowWindow(hMainWindow, SW_SHOW);
 197     if (!hParent)
 198         SetCursor(NULL);
 199
 200     while (GetMessage(&msg, NULL, 0, 0))
 201         DispatchMessage(&msg);
 202
 203     return msg.wParam;
 204 }
 205
 206 // Screen Saver entry point
 207 int APIENTRY _tWinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPTSTR CmdLine, int nCmdShow)
 208 {
 209     LPTSTR p;
 210
 211         UNREFERENCED_PARAMETER(nCmdShow);
 212         UNREFERENCED_PARAMETER(hPrevInst);
 213
 214     hMainInstance = hInst;
 215
 216     // Parse the arguments
 217     for (p = CmdLine; *p; p++)
 218     {
 219         switch (*p)
 220         {
 221             case 'S':
 222             case 's':
 223                 // Start the screen saver
 224                 return LaunchScreenSaver(NULL);
 225
 226             case 'P':
 227             case 'p':
 228             {
 229                 // Start the screen saver in preview mode
 230                 HWND hParent;
 231                 fChildPreview = TRUE;
 232
 233                 while (ISSPACE(*++p));
 234                 hParent = (HWND) _toulptr(p);
 235
 236                 if (hParent && IsWindow(hParent))
 237                     return LaunchScreenSaver(hParent);
 238             }
 239             return 0;
 240
 241             case 'C':
 242             case 'c':
 243                 // Display the configuration dialog
 244                 LaunchConfig();
 245                 return 0;
 246
 247             case '-':
 248             case '/':
 249             case ' ':
 250             default:
 251                 break;
 252         }
 253     }
 254
 255     LaunchConfig();
 256
 257     return 0;
 258 }