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