Fix bad logic in == NULL test.
[wine/multimedia.git] / windows / queue.c
blob4ac460810629a425a4d5237b2a74a1297d699895
1 /*
2 * Message queues related functions
4 * Copyright 1993, 1994 Alexandre Julliard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <string.h>
22 #include <signal.h>
23 #include <assert.h>
24 #include "windef.h"
25 #include "wingdi.h"
26 #include "winerror.h"
27 #include "wine/winbase16.h"
28 #include "wine/winuser16.h"
29 #include "message.h"
30 #include "win.h"
31 #include "user.h"
32 #include "thread.h"
33 #include "wine/debug.h"
34 #include "wine/server.h"
36 WINE_DEFAULT_DEBUG_CHANNEL(msg);
39 /***********************************************************************
40 * QUEUE_CreateMsgQueue
42 * Creates a message queue. Doesn't link it into queue list!
44 static HQUEUE16 QUEUE_CreateMsgQueue(void)
46 HQUEUE16 hQueue;
47 HANDLE handle;
48 MESSAGEQUEUE * msgQueue;
50 TRACE_(msg)("(): Creating message queue...\n");
52 if (!(hQueue = GlobalAlloc16( GMEM_FIXED | GMEM_ZEROINIT,
53 sizeof(MESSAGEQUEUE) )))
54 return 0;
56 msgQueue = (MESSAGEQUEUE *) GlobalLock16( hQueue );
57 if ( !msgQueue )
58 return 0;
60 SERVER_START_REQ( get_msg_queue )
62 wine_server_call_err( req );
63 handle = reply->handle;
65 SERVER_END_REQ;
66 if (!handle)
68 ERR_(msg)("Cannot get thread queue");
69 GlobalFree16( hQueue );
70 return 0;
72 msgQueue->server_queue = handle;
73 msgQueue->self = hQueue;
74 return hQueue;
78 /***********************************************************************
79 * QUEUE_Current
81 * Get the current thread queue, creating it if required.
82 * QUEUE_Unlock is not needed since the queue can only be deleted by
83 * the current thread anyway.
85 MESSAGEQUEUE *QUEUE_Current(void)
87 HQUEUE16 hQueue = NtCurrentTeb()->queue;
89 if (!hQueue)
91 if (!(hQueue = QUEUE_CreateMsgQueue())) return NULL;
92 SetThreadQueue16( 0, hQueue );
95 return GlobalLock16( hQueue );
100 /***********************************************************************
101 * QUEUE_DeleteMsgQueue
103 * Delete a message queue.
105 void QUEUE_DeleteMsgQueue(void)
107 HQUEUE16 hQueue = NtCurrentTeb()->queue;
108 MESSAGEQUEUE * msgQueue;
110 if (!hQueue) return; /* thread doesn't have a queue */
112 TRACE("(): Deleting message queue %04x\n", hQueue);
114 if (!(msgQueue = GlobalLock16( hQueue )))
116 ERR("invalid thread queue\n");
117 return;
120 SetThreadQueue16( 0, 0 );
121 CloseHandle( msgQueue->server_queue );
122 GlobalFree16( hQueue );
126 /***********************************************************************
127 * InitThreadInput (USER.409)
129 HQUEUE16 WINAPI InitThreadInput16( WORD unknown, WORD flags )
131 MESSAGEQUEUE *queue = QUEUE_Current();
132 return queue ? queue->self : 0;
135 /***********************************************************************
136 * GetQueueStatus (USER32.@)
138 DWORD WINAPI GetQueueStatus( UINT flags )
140 DWORD ret = 0;
142 SERVER_START_REQ( get_queue_status )
144 req->clear = 1;
145 wine_server_call( req );
146 ret = MAKELONG( reply->changed_bits & flags, reply->wake_bits & flags );
148 SERVER_END_REQ;
149 return ret;
153 /***********************************************************************
154 * GetInputState (USER32.@)
156 BOOL WINAPI GetInputState(void)
158 DWORD ret = 0;
160 SERVER_START_REQ( get_queue_status )
162 req->clear = 0;
163 wine_server_call( req );
164 ret = reply->wake_bits & (QS_KEY | QS_MOUSEBUTTON);
166 SERVER_END_REQ;
167 return ret;
170 /***********************************************************************
171 * GetMessagePos (USER.119)
172 * GetMessagePos (USER32.@)
174 * The GetMessagePos() function returns a long value representing a
175 * cursor position, in screen coordinates, when the last message
176 * retrieved by the GetMessage() function occurs. The x-coordinate is
177 * in the low-order word of the return value, the y-coordinate is in
178 * the high-order word. The application can use the MAKEPOINT()
179 * macro to obtain a POINT structure from the return value.
181 * For the current cursor position, use GetCursorPos().
183 * RETURNS
185 * Cursor position of last message on success, zero on failure.
187 * CONFORMANCE
189 * ECMA-234, Win32
192 DWORD WINAPI GetMessagePos(void)
194 MESSAGEQUEUE *queue;
196 if (!(queue = QUEUE_Current())) return 0;
197 return queue->GetMessagePosVal;
201 /***********************************************************************
202 * GetMessageTime (USER.120)
203 * GetMessageTime (USER32.@)
205 * GetMessageTime() returns the message time for the last message
206 * retrieved by the function. The time is measured in milliseconds with
207 * the same offset as GetTickCount().
209 * Since the tick count wraps, this is only useful for moderately short
210 * relative time comparisons.
212 * RETURNS
214 * Time of last message on success, zero on failure.
216 * CONFORMANCE
218 * ECMA-234, Win32
221 LONG WINAPI GetMessageTime(void)
223 MESSAGEQUEUE *queue;
225 if (!(queue = QUEUE_Current())) return 0;
226 return queue->GetMessageTimeVal;
230 /***********************************************************************
231 * GetMessageExtraInfo (USER.288)
232 * GetMessageExtraInfo (USER32.@)
234 LONG WINAPI GetMessageExtraInfo(void)
236 MESSAGEQUEUE *queue;
238 if (!(queue = QUEUE_Current())) return 0;
239 return queue->GetMessageExtraInfoVal;