windows-nt-4.0/private/ntos/w32/ntuser/kernel/capture.c

/****************************** Module Header ******************************\
* Module Name: capture.c
*
* Copyright (c) 1985-1996, Microsoft Corporation
*
* History:
* 08-Nov-1990 DavidPe   Created.
* 01-Feb-1991 MikeKe    Added Revalidation code
\***************************************************************************/

#include "precomp.h"
#pragma hdrstop

/***************************************************************************\
* xxxSetCapture (API)
*
* This function sets the capture window for the current queue.
*
* History:
* 08-Nov-1990 DavidPe   Created.
\***************************************************************************/

PWND xxxSetCapture(
    PWND pwnd)
{
    PQ   pq;
    PWND pwndCaptureOld;
    HWND hwndCaptureOld;

    pq = (PQ)PtiCurrent()->pq;

    /*
     * Don't allow the app to set capture to a window
     * from another queue.
     */
    if ((pwnd != NULL) && GETPTI(pwnd)->pq != pq)
        return NULL;

    /*
     * If full screen capture don't allow any other capture
     */
    if (gspwndScreenCapture)
        return NULL;

    pwndCaptureOld = pq->spwndCapture;
    hwndCaptureOld = HW(pwndCaptureOld);

    xxxCapture(PtiCurrent(), pwnd, CLIENT_CAPTURE);

    if (hwndCaptureOld != NULL) {

        if (RevalidateHwnd(hwndCaptureOld))
            return pwndCaptureOld;
    }

    return NULL;
}

/***************************************************************************\
* xxxReleaseCapture (API)
*
* This function release the capture for the current queue.
*
* History:
* 08-Nov-1990 DavidPe   Created.
* 16-May-1991 MikeKe    Changed to return BOOL
\***************************************************************************/

BOOL xxxReleaseCapture(VOID)
{
    PTHREADINFO ptiCurrent = PtiCurrent();

    /*
     * If we're releasing the capture from a window during tracking,
     * cancel tracking first.
     */
    if (ptiCurrent->pmsd != NULL) {

        /*
         * Only remove the tracking rectangle if it's
         * been made visible.
         */
        if (ptiCurrent->TIF_flags & TIF_TRACKRECTVISIBLE) {

            bSetDevDragRect(gpDispInfo->hDev, NULL, NULL);

            if (!(ptiCurrent->pmsd->fDragFullWindows))
                xxxDrawDragRect(ptiCurrent->pmsd, NULL, DDR_ENDCANCEL);

            ptiCurrent->TIF_flags &= ~(TIF_TRACKRECTVISIBLE | TIF_MOVESIZETRACKING);
        }
    }

    xxxCapture(ptiCurrent, NULL, NO_CAP_CLIENT);

    return TRUE;
}

/***************************************************************************\
* xxxCapture
*
* This is the workhorse routine of capture setting and releasing.
*
* History:
* 13-Nov-1990 DavidPe   Created.
\***************************************************************************/

VOID xxxCapture(
    PTHREADINFO pti,
    PWND        pwnd,
    UINT        code)
{
    if ((gspwndScreenCapture == NULL) ||
        (code == FULLSCREEN_CAPTURE) ||
        ((pwnd == NULL) && (code == NO_CAP_CLIENT) && (pti->pq != GETPTI(gspwndScreenCapture)->pq))) {

        PQ   pq;
        PWND pwndCaptureOld = NULL;

        if (code == FULLSCREEN_CAPTURE) {
            if (pwnd) {

                Lock(&gspwndScreenCapture, pwnd);

                /*
                 * We're going full screen so clear the mouse owner
                 */
                Unlock(&gspwndMouseOwner);

            } else {

                Unlock(&gspwndScreenCapture);
            }
        }

        /*
         * Internal capture works like Win 3.1 capture unlike the NT capture
         * which can be lost if the user clicks down on another application
         */
        if (code == CLIENT_CAPTURE_INTERNAL) {
            Lock(&gspwndInternalCapture, pwnd);
            code = CLIENT_CAPTURE;
        }

        /*
         * Free the internal capture if the app (thread) that did the internal
         * capture is freeing the capture.
         */
        if ((code == NO_CAP_CLIENT) &&
            gspwndInternalCapture   &&
            (pti == GETPTI(gspwndInternalCapture))) {

            Unlock(&gspwndInternalCapture);
        }

        if ((pq = pti->pq) != NULL) {

            /*
             * Make consistent picture of mouse tracking stuff for apps
             */
            if ((pq->spwndLastMouseMessage != NULL) &&
                    ((pwnd == pq->spwndLastMouseMessage) &&
                     (code != CLIENT_CAPTURE)) ||
                    ((pq->spwndCapture == pq->spwndLastMouseMessage) &&
                     (pq->codeCapture != CLIENT_CAPTURE))) {
                ResetMouseTracking(pq, NULL);
            }

            pwndCaptureOld = pq->spwndCapture;
            Lock(&pq->spwndCapture, pwnd);
            pq->codeCapture = code;
        }

        /*
         * If there was a capture window and we're releasing it, post
         * a WM_MOUSEMOVE to the window we're over so they can know about
         * the current mouse position.
         */
        if ((pwnd == NULL) && (pwndCaptureOld != NULL))
            SetFMouseMoved();

        /*
         * New for win95 - send  WM_CAPTURECHANGED.
         *
         * The FNID_DELETED_BIT is set in xxxFreeWindow which means we
         * DON'T want to send the message.
         */
        if (pwndCaptureOld                        &&
            TestWF(pwndCaptureOld, WFWIN40COMPAT) &&
            !(pwndCaptureOld->fnid & FNID_DELETED_BIT)) {

            TL tlpwnd;

            ThreadLock(pwndCaptureOld, &tlpwnd);
            xxxSendMessageCallback(pwndCaptureOld,
                    WM_CAPTURECHANGED,
                    FALSE,
                    (LPARAM)HW(pwnd),
                    NULL,
                    0,
                    FALSE);
            ThreadUnlock(&tlpwnd);
        }
    }
}