simplify code so it always returns the same object

[wxWidgets.git] / src / gtk1 / app.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        src/gtk1/app.cpp
// Purpose:
// Author:      Robert Roebling
// Id:          $Id$
// Copyright:   (c) 1998 Robert Roebling, Julian Smart
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"

#include "wx/app.h"

#ifndef WX_PRECOMP
    #include "wx/intl.h"
    #include "wx/log.h"
    #include "wx/utils.h"
    #include "wx/dialog.h"
    #include "wx/settings.h"
    #include "wx/msgdlg.h"
    #include "wx/memory.h"
    #include "wx/font.h"
    #include "wx/gdicmn.h"
    #include "wx/image.h"
    #include "wx/module.h"
#endif

#include "wx/file.h"
#include "wx/filename.h"
#include "wx/thread.h"

#ifdef __WXGPE__
#include <gpe/init.h>
#endif

#ifdef __WXUNIVERSAL__
    #include "wx/univ/theme.h"
    #include "wx/univ/renderer.h"
#endif

#if wxUSE_THREADS
    #include "wx/thread.h"
#endif

#include <unistd.h>

#ifdef HAVE_POLL
    #if defined(__VMS)
        #include <poll.h>
    #else
        // bug in the OpenBSD headers: at least in 3.1 there is no extern "C"
        // in neither poll.h nor sys/poll.h which results in link errors later
        #ifdef __OPENBSD__
            extern "C"
            {
        #endif

        #include <sys/poll.h>

        #ifdef __OPENBSD__
            };
        #endif
    #endif // platform
#else // !HAVE_POLL
    // we implement poll() ourselves using select() which is supposed exist in
    // all modern Unices
    #include <sys/types.h>
    #include <sys/time.h>
    #include <unistd.h>
    #ifdef HAVE_SYS_SELECT_H
        #include <sys/select.h>
    #endif
#endif // HAVE_POLL/!HAVE_POLL

#include "wx/unix/private.h"
#include "wx/gtk1/win_gtk.h"

#include <gtk/gtk.h>

//-----------------------------------------------------------------------------
// global data
//-----------------------------------------------------------------------------

bool   g_mainThreadLocked = false;
gint   g_pendingTag = 0;

static GtkWidget *gs_RootWindow = NULL;

//-----------------------------------------------------------------------------
// idle system
//-----------------------------------------------------------------------------

extern bool g_isIdle;

void wxapp_install_idle_handler();

#if wxUSE_THREADS
static wxMutex gs_idleTagsMutex;
#endif


//-----------------------------------------------------------------------------
// wxWakeUpIdle
//-----------------------------------------------------------------------------

// RR/KH: The wxMutexGui calls are not needed on GTK2 according to
// the GTK faq, http://www.gtk.org/faq/#AEN500
// The calls to gdk_threads_enter() and leave() are specifically noted
// as not being necessary.  The MutexGui calls are still left in for GTK1.
// Eliminating the MutexGui calls fixes the long-standing "random" lockup
// when using wxPostEvent (which calls WakeUpIdle) from a thread.

void wxApp::WakeUpIdle()
{
#if wxUSE_THREADS
    if (!wxThread::IsMain())
        wxMutexGuiEnter();
#endif // wxUSE_THREADS

    wxapp_install_idle_handler();

#if wxUSE_THREADS
    if (!wxThread::IsMain())
        wxMutexGuiLeave();
#endif // wxUSE_THREADS
}

//-----------------------------------------------------------------------------
// local functions
//-----------------------------------------------------------------------------

// the callback functions must be extern "C" to comply with GTK+ declarations
extern "C"
{

static gint wxapp_pending_callback( gpointer WXUNUSED(data) )
{
    if (!wxTheApp) return TRUE;

    // When getting called from GDK's time-out handler
    // we are no longer within GDK's grab on the GUI
    // thread so we must lock it here ourselves.
    gdk_threads_enter();

    // Sent idle event to all who request them.
    wxTheApp->ProcessPendingEvents();

    {
#if wxUSE_THREADS
        wxMutexLocker lock(gs_idleTagsMutex);
#endif
        g_pendingTag = 0;
    }

    // Flush the logged messages if any.
#if wxUSE_LOG
    wxLog::FlushActive();
#endif // wxUSE_LOG

    // Release lock again
    gdk_threads_leave();

    // Return FALSE to indicate that no more idle events are
    // to be sent (single shot instead of continuous stream)
    return FALSE;
}

static gint wxapp_idle_callback( gpointer WXUNUSED(data) )
{
    if (!wxTheApp)
        return TRUE;

#if wxDEBUG_LEVEL
    // don't generate the idle events while the assert modal dialog is shown,
    // this completely confuses the apps which don't expect to be reentered
    // from some safely-looking functions
    if ( wxTheApp->IsInAssert() )
    {
        // But repaint the assertion message if necessary
        if (wxTopLevelWindows.GetCount() > 0)
        {
            wxWindow* win = (wxWindow*) wxTopLevelWindows.GetLast()->GetData();
            if (win->IsKindOf(CLASSINFO(wxGenericMessageDialog)))
                win->OnInternalIdle();
        }
        return TRUE;
    }
#endif // wxDEBUG_LEVEL

    // When getting called from GDK's time-out handler
    // we are no longer within GDK's grab on the GUI
    // thread so we must lock it here ourselves.
    gdk_threads_enter();

    // Indicate that we are now in idle mode and event handlers
    // will have to reinstall the idle handler again.
    {
#if wxUSE_THREADS
        wxMutexLocker lock(gs_idleTagsMutex);
#endif
        g_isIdle = TRUE;
        wxTheApp->m_idleTag = 0;
    }

    // Send idle event to all who request them as long as
    // no events have popped up in the event queue.
    while (wxTheApp->ProcessIdle() && (gtk_events_pending() == 0))
        ;

    // Release lock again
    gdk_threads_leave();

    // Return FALSE to indicate that no more idle events are
    // to be sent (single shot instead of continuous stream).
    return FALSE;
}

#if wxUSE_THREADS

#ifdef HAVE_POLL
    #define wxPoll poll
    #define wxPollFd pollfd
#else // !HAVE_POLL

typedef GPollFD wxPollFd;

int wxPoll(wxPollFd *ufds, unsigned int nfds, int timeout)
{
    // convert timeout from ms to struct timeval (s/us)
    timeval tv_timeout;
    tv_timeout.tv_sec = timeout/1000;
    tv_timeout.tv_usec = (timeout%1000)*1000;

    // remember the highest fd used here
    int fdMax = -1;

    // and fill the sets for select()
    fd_set readfds;
    fd_set writefds;
    fd_set exceptfds;
    wxFD_ZERO(&readfds);
    wxFD_ZERO(&writefds);
    wxFD_ZERO(&exceptfds);

    unsigned int i;
    for ( i = 0; i < nfds; i++ )
    {
        wxASSERT_MSG( ufds[i].fd < FD_SETSIZE, wxT("fd out of range") );

        if ( ufds[i].events & G_IO_IN )
            wxFD_SET(ufds[i].fd, &readfds);

        if ( ufds[i].events & G_IO_PRI )
            wxFD_SET(ufds[i].fd, &exceptfds);

        if ( ufds[i].events & G_IO_OUT )
            wxFD_SET(ufds[i].fd, &writefds);

        if ( ufds[i].fd > fdMax )
            fdMax = ufds[i].fd;
    }

    fdMax++;
    int res = select(fdMax, &readfds, &writefds, &exceptfds, &tv_timeout);

    // translate the results back
    for ( i = 0; i < nfds; i++ )
    {
        ufds[i].revents = 0;

        if ( wxFD_ISSET(ufds[i].fd, &readfds ) )
            ufds[i].revents |= G_IO_IN;

        if ( wxFD_ISSET(ufds[i].fd, &exceptfds ) )
            ufds[i].revents |= G_IO_PRI;

        if ( wxFD_ISSET(ufds[i].fd, &writefds ) )
            ufds[i].revents |= G_IO_OUT;
    }

    return res;
}

#endif // HAVE_POLL/!HAVE_POLL

static gint wxapp_poll_func( GPollFD *ufds, guint nfds, gint timeout )
{
    gdk_threads_enter();

    wxMutexGuiLeave();
    g_mainThreadLocked = true;

    // we rely on the fact that glib GPollFD struct is really just pollfd but
    // I wonder how wise is this in the long term (VZ)
    gint res = wxPoll( (wxPollFd *) ufds, nfds, timeout );

    wxMutexGuiEnter();
    g_mainThreadLocked = false;

    gdk_threads_leave();

    return res;
}

#endif // wxUSE_THREADS

} // extern "C"

void wxapp_install_idle_handler()
{
#if wxUSE_THREADS
    wxMutexLocker lock(gs_idleTagsMutex);
#endif

    // Don't install the handler if it's already installed. This test *MUST*
    // be done when gs_idleTagsMutex is locked!
    if (!g_isIdle)
        return;

    // GD: this assert is raised when using the thread sample (which works)
    //     so the test is probably not so easy. Can widget callbacks be
    //     triggered from child threads and, if so, for which widgets?
    // wxASSERT_MSG( wxThread::IsMain() || gs_WakeUpIdle, wxT("attempt to install idle handler from widget callback in child thread (should be exclusively from wxWakeUpIdle)") );

    wxASSERT_MSG( wxTheApp->m_idleTag == 0, wxT("attempt to install idle handler twice") );

    g_isIdle = false;

    if (g_pendingTag == 0)
        g_pendingTag = gtk_idle_add_priority( 900, wxapp_pending_callback, (gpointer) NULL );

    // This routine gets called by all event handlers
    // indicating that the idle is over. It may also
    // get called from other thread for sending events
    // to the main thread (and processing these in
    // idle time). Very low priority.
    wxTheApp->m_idleTag = gtk_idle_add_priority( 1000, wxapp_idle_callback, (gpointer) NULL );
}

static bool wxOKlibc()
{
#if defined(__UNIX__) && defined(__GLIBC__)
    // glibc 2.0 uses UTF-8 even when it shouldn't
    wchar_t res = 0;
    if ((MB_CUR_MAX == 2) &&
        (wxMB2WC(&res, "\xdd\xa5", 1) == 1) &&
        (res==0x765))
    {
        // this is UTF-8 allright, check whether that's what we want
        char *cur_locale = setlocale(LC_CTYPE, NULL);
        if ((strlen(cur_locale) < 4) ||
        (strcasecmp(cur_locale + strlen(cur_locale) - 4, "utf8")) ||
        (strcasecmp(cur_locale + strlen(cur_locale) - 5, "utf-8"))) {
        // nope, don't use libc conversion
        return false;
        }
    }
#endif
    return true;
}

//-----------------------------------------------------------------------------
// Access to the root window global
//-----------------------------------------------------------------------------

GtkWidget* wxGetRootWindow()
{
    if (gs_RootWindow == NULL)
    {
        gs_RootWindow = gtk_window_new( GTK_WINDOW_TOPLEVEL );
        gtk_widget_realize( gs_RootWindow );
    }
    return gs_RootWindow;
}

//-----------------------------------------------------------------------------
// wxApp
//-----------------------------------------------------------------------------

IMPLEMENT_DYNAMIC_CLASS(wxApp,wxEvtHandler)

wxApp::wxApp()
{
    m_isInAssert = false;

    m_idleTag = 0;
    g_isIdle = TRUE;
    wxapp_install_idle_handler();

#if wxUSE_THREADS
    g_main_set_poll_func( wxapp_poll_func );
#endif

    m_colorCube = (unsigned char*) NULL;

    // this is NULL for a "regular" wxApp, but is set (and freed) by a wxGLApp
    m_glVisualInfo = NULL;
    m_glFBCInfo = NULL;
}

wxApp::~wxApp()
{
    if (m_idleTag) gtk_idle_remove( m_idleTag );

    if (m_colorCube) free(m_colorCube);
}

bool wxApp::OnInitGui()
{
    if ( !wxAppBase::OnInitGui() )
        return false;

    GdkVisual *visual = gdk_visual_get_system();

    // if this is a wxGLApp (derived from wxApp), and we've already
    // chosen a specific visual, then derive the GdkVisual from that
    if (m_glVisualInfo != NULL)
    {
        GdkVisual* vis = gdkx_visual_get(
            ((XVisualInfo *) m_glVisualInfo) ->visualid );
        gtk_widget_set_default_visual( vis );

        GdkColormap *colormap = gdk_colormap_new( vis, FALSE );
        gtk_widget_set_default_colormap( colormap );

        visual = vis;
    }

    // On some machines, the default visual is just 256 colours, so
    // we make sure we get the best. This can sometimes be wasteful.

    else
    if ((gdk_visual_get_best() != gdk_visual_get_system()) && (m_useBestVisual))
    {
        GdkVisual* vis = gdk_visual_get_best();
        gtk_widget_set_default_visual( vis );

        GdkColormap *colormap = gdk_colormap_new( vis, FALSE );
        gtk_widget_set_default_colormap( colormap );

        visual = vis;
    }

    // Nothing to do for 15, 16, 24, 32 bit displays
    if (visual->depth > 8) return TRUE;

    // initialize color cube for 8-bit color reduction dithering

    GdkColormap *cmap = gtk_widget_get_default_colormap();

    m_colorCube = (unsigned char*)malloc(32 * 32 * 32);

    for (int r = 0; r < 32; r++)
    {
        for (int g = 0; g < 32; g++)
        {
            for (int b = 0; b < 32; b++)
            {
                int rr = (r << 3) | (r >> 2);
                int gg = (g << 3) | (g >> 2);
                int bb = (b << 3) | (b >> 2);

                int index = -1;

                GdkColor *colors = cmap->colors;
                if (colors)
                {
                    int max = 3 * 65536;

                    for (int i = 0; i < cmap->size; i++)
                    {
                        int rdiff = ((rr << 8) - colors[i].red);
                        int gdiff = ((gg << 8) - colors[i].green);
                        int bdiff = ((bb << 8) - colors[i].blue);
                        int sum = ABS (rdiff) + ABS (gdiff) + ABS (bdiff);
                        if (sum < max)
                        {
                            index = i; max = sum;
                        }
                    }
                }
                else
                {
                    // assume 8-bit true or static colors. this really exists
                    GdkVisual* vis = gdk_colormap_get_visual( cmap );
                    index = (r >> (5 - vis->red_prec)) << vis->red_shift;
                    index |= (g >> (5 - vis->green_prec)) << vis->green_shift;
                    index |= (b >> (5 - vis->blue_prec)) << vis->blue_shift;
                }
                m_colorCube[ (r*1024) + (g*32) + b ] = index;
            }
        }
    }

    return true;
}

GdkVisual *wxApp::GetGdkVisual()
{
    GdkVisual *visual = NULL;

    if (m_glVisualInfo)
        visual = gdkx_visual_get( ((XVisualInfo *) m_glVisualInfo)->visualid );
    else
        visual = gdk_window_get_visual( wxGetRootWindow()->window );

    wxASSERT( visual );

    return visual;
}

bool wxApp::Initialize(int& argc, wxChar **argv)
{
    bool init_result;

#if wxUSE_THREADS
    // GTK 1.2 up to version 1.2.3 has broken threads
    if ((gtk_major_version == 1) &&
        (gtk_minor_version == 2) &&
        (gtk_micro_version < 4))
    {
        printf( "wxWidgets warning: GUI threading disabled due to outdated GTK version\n" );
    }
    else
    {
        if (!g_thread_supported())
            g_thread_init(NULL);
    }
#endif // wxUSE_THREADS

    gtk_set_locale();

    if (!wxOKlibc())
        wxConvCurrent = &wxConvLocal;

#if wxUSE_UNICODE
    // gtk_init() wants UTF-8, not wchar_t, so convert
    int i;
    char **argvGTK = new char *[argc + 1];
    for ( i = 0; i < argc; i++ )
    {
        argvGTK[i] = wxStrdupA(wxConvUTF8.cWX2MB(argv[i]));
    }

    argvGTK[argc] = NULL;

    int argcGTK = argc;

#ifdef __WXGPE__
    init_result = true;  // is there a _check() version of this?
    gpe_application_init( &argcGTK, &argvGTK );
#else
    init_result = gtk_init_check( &argcGTK, &argvGTK );
#endif

    if ( argcGTK != argc )
    {
        // we have to drop the parameters which were consumed by GTK+
        for ( i = 0; i < argcGTK; i++ )
        {
            while ( strcmp(wxConvUTF8.cWX2MB(argv[i]), argvGTK[i]) != 0 )
            {
                memmove(argv + i, argv + i + 1, argc - i);
            }
        }

        argc = argcGTK;
    }
    //else: gtk_init() didn't modify our parameters

    // free our copy
    for ( i = 0; i < argcGTK; i++ )
    {
        free(argvGTK[i]);
    }

    delete [] argvGTK;
#else // !wxUSE_UNICODE
    // gtk_init() shouldn't actually change argv itself (just its contents) so
    // it's ok to pass pointer to it
    init_result = gtk_init_check( &argc, &argv );
#endif // wxUSE_UNICODE/!wxUSE_UNICODE

    if (!init_result) {
        wxLogError(wxT("Unable to initialize gtk, is DISPLAY set properly?"));
        return false;
    }

    // we cannot enter threads before gtk_init is done
    gdk_threads_enter();

    if ( !wxAppBase::Initialize(argc, argv) )
    {
        gdk_threads_leave();

        return false;
    }

    wxSetDetectableAutoRepeat( TRUE );

#if wxUSE_INTL
    wxFont::SetDefaultEncoding(wxLocale::GetSystemEncoding());
#endif

    return true;
}

void wxApp::CleanUp()
{
    gdk_threads_leave();

    wxAppBase::CleanUp();
}

void wxApp::OnAssertFailure(const wxChar *file,
                            int line,
                            const wxChar* func,
                            const wxChar* cond,
                            const wxChar *msg)
{
    // there is no need to do anything if asserts are disabled in this build
    // anyhow
#if wxDEBUG_LEVEL
    // block wx idle events while assert dialog is showing
    m_isInAssert = true;

    wxAppBase::OnAssertFailure(file, line, func, cond, msg);

    m_isInAssert = false;
#else // !wxDEBUG_LEVEL
    wxUnusedVar(file);
    wxUnusedVar(line);
    wxUnusedVar(func);
    wxUnusedVar(cond);
    wxUnusedVar(msg);
#endif // wxDEBUG_LEVEL/!wxDEBUG_LEVEL
}

void wxApp::RemoveIdleTag()
{
#if wxUSE_THREADS
    wxMutexLocker lock(gs_idleTagsMutex);
#endif
    if (!g_isIdle)
    {
        gtk_idle_remove( wxTheApp->m_idleTag );
        wxTheApp->m_idleTag = 0;
        g_isIdle = true;
    }
}