/*
 * X11 clipboard windows driver
 *
 * Copyright 1994 Martin Ayotte
 * Copyright 1996 Alex Korobka
 * Copyright 1999 Noel Borthwick
 * Copyright 2003 Ulrich Czekalla for CodeWeavers
 * Copyright 2014 Damjan Jovanovic
 * Copyright 2016 Alexandre Julliard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 *
 * NOTES:
 *    This file contains the X specific implementation for the windows
 *    Clipboard API.
 *
 *    Wine's internal clipboard is exposed to external apps via the X
 *    selection mechanism.
 *    Currently the driver asserts ownership via two selection atoms:
 *    1. PRIMARY(XA_PRIMARY)
 *    2. CLIPBOARD
 *
 *    In our implementation, the CLIPBOARD selection takes precedence over PRIMARY,
 *    i.e. if a CLIPBOARD selection is available, it is used instead of PRIMARY.
 *    When Wine takes ownership of the clipboard, it takes ownership of BOTH selections.
 *    While giving up selection ownership, if the CLIPBOARD selection is lost,
 *    it will lose both PRIMARY and CLIPBOARD and empty the clipboard.
 *    However if only PRIMARY is lost, it will continue to hold the CLIPBOARD selection
 *    (leaving the clipboard cache content unaffected).
 *
 *      Every format exposed via a windows clipboard format is also exposed through
 *    a corresponding X selection target. A selection target atom is synthesized
 *    whenever a new Windows clipboard format is registered via RegisterClipboardFormat,
 *    or when a built-in format is used for the first time.
 *    Windows native format are exposed by prefixing the format name with "<WCF>"
 *    This allows us to uniquely identify windows native formats exposed by other
 *    running WINE apps.
 *
 *      In order to allow external applications to query WINE for supported formats,
 *    we respond to the "TARGETS" selection target. (See EVENT_SelectionRequest
 *    for implementation) We use the same mechanism to query external clients for
 *    availability of a particular format, by caching the list of available targets
 *    by using the clipboard cache's "delayed render" mechanism. If a selection client
 *    does not support the "TARGETS" selection target, we actually attempt to retrieve
 *    the format requested as a fallback mechanism.
 *
 *      Certain Windows native formats are automatically converted to X native formats
 *    and vice versa. If a native format is available in the selection, it takes
 *    precedence, in order to avoid unnecessary conversions.
 *
 * FIXME: global format list needs a critical section
 */

#include "config.h"
#include "wine/port.h"

#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <fcntl.h>
#include <limits.h>
#include <time.h>
#include <assert.h>

#include "windef.h"
#include "winbase.h"
#include "shlobj.h"
#include "shellapi.h"
#include "shlwapi.h"
#include "x11drv.h"
#include "wine/list.h"
#include "wine/debug.h"
#include "wine/unicode.h"

WINE_DEFAULT_DEBUG_CHANNEL(clipboard);

/* Maximum wait time for selection notify */
#define SELECTION_RETRIES 500  /* wait for .5 seconds */
#define SELECTION_WAIT    1000 /* us */

#define SELECTION_UPDATE_DELAY 2000   /* delay between checks of the X11 selection */

typedef BOOL (*EXPORTFUNC)( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
typedef HANDLE (*IMPORTFUNC)( Atom type, const void *data, size_t size );

struct clipboard_format
{
    struct list entry;
    UINT        id;
    Atom        atom;
    IMPORTFUNC  import;
    EXPORTFUNC  export;
};

static HANDLE import_data( Atom type, const void *data, size_t size );
static HANDLE import_enhmetafile( Atom type, const void *data, size_t size );
static HANDLE import_pixmap( Atom type, const void *data, size_t size );
static HANDLE import_image_bmp( Atom type, const void *data, size_t size );
static HANDLE import_string( Atom type, const void *data, size_t size );
static HANDLE import_utf8_string( Atom type, const void *data, size_t size );
static HANDLE import_compound_text( Atom type, const void *data, size_t size );
static HANDLE import_text( Atom type, const void *data, size_t size );
static HANDLE import_text_uri_list( Atom type, const void *data, size_t size );
static HANDLE import_targets( Atom type, const void *data, size_t size );

static BOOL export_data( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_string( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_utf8_string( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_text( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_compound_text( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_pixmap( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_image_bmp( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_enhmetafile( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_text_html( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_hdrop( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_targets( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_multiple( Display *display, Window win, Atom prop, Atom target, HANDLE handle );
static BOOL export_timestamp( Display *display, Window win, Atom prop, Atom target, HANDLE handle );

static BOOL X11DRV_CLIPBOARD_ReadProperty( Display *display, Window w, Atom prop,
                                           Atom *type, unsigned char **data, unsigned long *datasize );

/* Clipboard formats */

static const WCHAR RichTextFormatW[] = {'R','i','c','h',' ','T','e','x','t',' ','F','o','r','m','a','t',0};
static const WCHAR GIFW[] = {'G','I','F',0};
static const WCHAR JFIFW[] = {'J','F','I','F',0};
static const WCHAR PNGW[] = {'P','N','G',0};
static const WCHAR HTMLFormatW[] = {'H','T','M','L',' ','F','o','r','m','a','t',0};

static const struct
{
    const WCHAR  *name;
    UINT          id;
    UINT          data;
    IMPORTFUNC    import;
    EXPORTFUNC    export;
} builtin_formats[] =
{
    { 0, CF_UNICODETEXT,     XATOM_UTF8_STRING,         import_utf8_string,   export_utf8_string },
    { 0, CF_UNICODETEXT,     XATOM_COMPOUND_TEXT,       import_compound_text, export_compound_text },
    { 0, CF_UNICODETEXT,     XA_STRING,                 import_string,        export_string },
    { 0, CF_UNICODETEXT,     XATOM_text_plain,          import_string,        export_string },
    { 0, CF_UNICODETEXT,     XATOM_TEXT,                import_text,          export_text },
    { 0, CF_SYLK,            XATOM_WCF_SYLK,            import_data,          export_data },
    { 0, CF_DIF,             XATOM_WCF_DIF,             import_data,          export_data },
    { 0, CF_TIFF,            XATOM_WCF_TIFF,            import_data,          export_data },
    { 0, CF_DIB,             XA_PIXMAP,                 import_pixmap,        export_pixmap },
    { 0, CF_PENDATA,         XATOM_WCF_PENDATA,         import_data,          export_data },
    { 0, CF_RIFF,            XATOM_WCF_RIFF,            import_data,          export_data },
    { 0, CF_WAVE,            XATOM_WCF_WAVE,            import_data,          export_data },
    { 0, CF_ENHMETAFILE,     XATOM_WCF_ENHMETAFILE,     import_enhmetafile,   export_enhmetafile },
    { 0, CF_HDROP,           XATOM_text_uri_list,       import_text_uri_list, export_hdrop },
    { 0, CF_DIB,             XATOM_image_bmp,           import_image_bmp,     export_image_bmp },
    { RichTextFormatW, 0,    XATOM_text_rtf,            import_data,          export_data },
    { RichTextFormatW, 0,    XATOM_text_richtext,       import_data,          export_data },
    { GIFW, 0,               XATOM_image_gif,           import_data,          export_data },
    { JFIFW, 0,              XATOM_image_jpeg,          import_data,          export_data },
    { PNGW, 0,               XATOM_image_png,           import_data,          export_data },
    { HTMLFormatW, 0,        XATOM_HTML_Format,         import_data,          export_data },
    { HTMLFormatW, 0,        XATOM_text_html,           import_data,          export_text_html },
    { 0, 0,                  XATOM_TARGETS,             import_targets,       export_targets },
    { 0, 0,                  XATOM_MULTIPLE,            NULL,                 export_multiple },
    { 0, 0,                  XATOM_TIMESTAMP,           NULL,                 export_timestamp },
};

static struct list format_list = LIST_INIT( format_list );

#define NB_BUILTIN_FORMATS (sizeof(builtin_formats) / sizeof(builtin_formats[0]))
#define GET_ATOM(prop)  (((prop) < FIRST_XATOM) ? (Atom)(prop) : X11DRV_Atoms[(prop) - FIRST_XATOM])

static DWORD clipboard_thread_id;
static HWND clipboard_hwnd;
static BOOL is_clipboard_owner;
static Window selection_window;
static Window import_window;
static Atom current_selection;
static ULONG64 last_clipboard_update;
static struct clipboard_format **current_x11_formats;
static unsigned int nb_current_x11_formats;

Display *clipboard_display = NULL;

static const char *debugstr_format( UINT id )
{
    WCHAR buffer[256];

    if (GetClipboardFormatNameW( id, buffer, 256 ))
        return wine_dbg_sprintf( "%04x %s", id, debugstr_w(buffer) );

    switch (id)
    {
    case 0: return "(none)";
#define BUILTIN(id) case id: return #id;
    BUILTIN(CF_TEXT)
    BUILTIN(CF_BITMAP)
    BUILTIN(CF_METAFILEPICT)
    BUILTIN(CF_SYLK)
    BUILTIN(CF_DIF)
    BUILTIN(CF_TIFF)
    BUILTIN(CF_OEMTEXT)
    BUILTIN(CF_DIB)
    BUILTIN(CF_PALETTE)
    BUILTIN(CF_PENDATA)
    BUILTIN(CF_RIFF)
    BUILTIN(CF_WAVE)
    BUILTIN(CF_UNICODETEXT)
    BUILTIN(CF_ENHMETAFILE)
    BUILTIN(CF_HDROP)
    BUILTIN(CF_LOCALE)
    BUILTIN(CF_DIBV5)
    BUILTIN(CF_OWNERDISPLAY)
    BUILTIN(CF_DSPTEXT)
    BUILTIN(CF_DSPBITMAP)
    BUILTIN(CF_DSPMETAFILEPICT)
    BUILTIN(CF_DSPENHMETAFILE)
#undef BUILTIN
    default: return wine_dbg_sprintf( "%04x", id );
    }
}

static const char *debugstr_xatom( Atom atom )
{
    const char *ret;
    char *name;

    if (!atom) return "(None)";
    name = XGetAtomName( thread_display(), atom );
    ret = debugstr_a( name );
    XFree( name );
    return ret;
}


static int is_atom_error( Display *display, XErrorEvent *event, void *arg )
{
    return (event->error_code == BadAtom);
}


/**************************************************************************
 *		find_win32_format
 */
static struct clipboard_format *find_win32_format( UINT id )
{
    struct clipboard_format *format;

    LIST_FOR_EACH_ENTRY( format, &format_list, struct clipboard_format, entry )
        if (format->id == id) return format;
    return NULL;
}


/**************************************************************************
 *		find_x11_format
 */
static struct clipboard_format *find_x11_format( Atom atom )
{
    struct clipboard_format *format;

    LIST_FOR_EACH_ENTRY( format, &format_list, struct clipboard_format, entry )
        if (format->atom == atom) return format;
    return NULL;
}


/**************************************************************************
 *		register_builtin_formats
 */
static void register_builtin_formats(void)
{
    struct clipboard_format *formats;
    unsigned int i;

    if (!(formats = HeapAlloc( GetProcessHeap(), 0, NB_BUILTIN_FORMATS * sizeof(*formats)))) return;

    for (i = 0; i < NB_BUILTIN_FORMATS; i++)
    {
        if (builtin_formats[i].name)
            formats[i].id = RegisterClipboardFormatW( builtin_formats[i].name );
        else
            formats[i].id = builtin_formats[i].id;

        formats[i].atom   = GET_ATOM(builtin_formats[i].data);
        formats[i].import = builtin_formats[i].import;
        formats[i].export = builtin_formats[i].export;
        list_add_tail( &format_list, &formats[i].entry );
    }
}


/**************************************************************************
 *		register_formats
 */
static void register_formats( const UINT *ids, const Atom *atoms, unsigned int count )
{
    struct clipboard_format *formats;
    unsigned int i;

    if (!(formats = HeapAlloc( GetProcessHeap(), 0, count * sizeof(*formats)))) return;

    for (i = 0; i < count; i++)
    {
        formats[i].id     = ids[i];
        formats[i].atom   = atoms[i];
        formats[i].import = import_data;
        formats[i].export = export_data;
        list_add_tail( &format_list, &formats[i].entry );
        TRACE( "registered %s atom %s\n", debugstr_format( ids[i] ), debugstr_xatom( atoms[i] ));
    }
}


/**************************************************************************
 *		register_win32_formats
 *
 * Register Win32 clipboard formats the first time we encounter them.
 */
static void register_win32_formats( const UINT *ids, UINT size )
{
    unsigned int count, len;
    UINT new_ids[256];
    char *names[256];
    Atom atoms[256];
    WCHAR buffer[256];

    if (list_empty( &format_list)) register_builtin_formats();

    while (size)
    {
        for (count = 0; count < 256 && size; ids++, size--)
        {
            if (find_win32_format( *ids )) continue;  /* it already exists */
            if (!GetClipboardFormatNameW( *ids, buffer, 256 )) continue;  /* not a named format */
            if (!(len = WideCharToMultiByte( CP_UNIXCP, 0, buffer, -1, NULL, 0, NULL, NULL ))) continue;
            if (!(names[count] = HeapAlloc( GetProcessHeap(), 0, len ))) continue;
            WideCharToMultiByte( CP_UNIXCP, 0, buffer, -1, names[count], len, NULL, NULL );
            new_ids[count++] = *ids;
        }
        if (!count) return;

        XInternAtoms( thread_display(), names, count, False, atoms );
        register_formats( new_ids, atoms, count );
        while (count) HeapFree( GetProcessHeap(), 0, names[--count] );
    }
}


/**************************************************************************
 *		register_x11_formats
 *
 * Register X11 atom formats the first time we encounter them.
 */
static void register_x11_formats( const Atom *atoms, UINT size )
{
    Display *display = thread_display();
    unsigned int i, pos, count;
    char *names[256];
    UINT ids[256];
    Atom new_atoms[256];
    WCHAR buffer[256];

    if (list_empty( &format_list)) register_builtin_formats();

    while (size)
    {
        for (count = 0; count < 256 && size; atoms++, size--)
            if (!find_x11_format( *atoms )) new_atoms[count++] = *atoms;

        if (!count) return;

        X11DRV_expect_error( display, is_atom_error, NULL );
        if (!XGetAtomNames( display, new_atoms, count, names )) count = 0;
        if (X11DRV_check_error())
        {
            WARN( "got some bad atoms, ignoring\n" );
            count = 0;
        }

        for (i = pos = 0; i < count; i++)
        {
            if (MultiByteToWideChar( CP_UNIXCP, 0, names[i], -1, buffer, 256 ) &&
                (ids[pos] = RegisterClipboardFormatW( buffer )))
                new_atoms[pos++] = new_atoms[i];
            XFree( names[i] );
        }
        register_formats( ids, new_atoms, pos );
    }
}


/**************************************************************************
 *		put_property
 *
 * Put data as a property on the specified window.
 */
static void put_property( Display *display, Window win, Atom prop, Atom type, int format,
                          const void *ptr, size_t size )
{
    const unsigned char *data = ptr;
    int mode = PropModeReplace;
    size_t width = (format == 32) ? sizeof(long) : format / 8;
    size_t max_size = XExtendedMaxRequestSize( display ) * 4;

    if (!max_size) max_size = XMaxRequestSize( display ) * 4;
    max_size -= 64; /* request overhead */

    do
    {
        size_t count = min( size, max_size / width );
        XChangeProperty( display, win, prop, type, format, mode, data, count );
        mode = PropModeAppend;
        size -= count;
        data += count * width;
    } while (size > 0);
}


/**************************************************************************
 *		convert_selection
 */
static Atom convert_selection( Display *display, Window win, Atom selection, Atom target )
{
    int i;
    XEvent event;

    XConvertSelection( display, selection, target, x11drv_atom(SELECTION_DATA), win, CurrentTime );

    for (i = 0; i < SELECTION_RETRIES; i++)
    {
        Bool res = XCheckTypedWindowEvent( display, win, SelectionNotify, &event );
        if (res && event.xselection.selection == selection && event.xselection.target == target)
            return event.xselection.property;
        usleep( SELECTION_WAIT );
    }
    ERR( "Timed out waiting for SelectionNotify event\n" );
    return None;
}


/***********************************************************************
 *           bitmap_info_size
 *
 * Return the size of the bitmap info structure including color table.
 */
static int bitmap_info_size( const BITMAPINFO * info, WORD coloruse )
{
    unsigned int colors, size, masks = 0;

    if (info->bmiHeader.biSize == sizeof(BITMAPCOREHEADER))
    {
        const BITMAPCOREHEADER *core = (const BITMAPCOREHEADER *)info;
        colors = (core->bcBitCount <= 8) ? 1 << core->bcBitCount : 0;
        return sizeof(BITMAPCOREHEADER) + colors *
             ((coloruse == DIB_RGB_COLORS) ? sizeof(RGBTRIPLE) : sizeof(WORD));
    }
    else  /* assume BITMAPINFOHEADER */
    {
        colors = info->bmiHeader.biClrUsed;
        if (!colors && (info->bmiHeader.biBitCount <= 8))
            colors = 1 << info->bmiHeader.biBitCount;
        if (info->bmiHeader.biCompression == BI_BITFIELDS) masks = 3;
        size = max( info->bmiHeader.biSize, sizeof(BITMAPINFOHEADER) + masks * sizeof(DWORD) );
        return size + colors * ((coloruse == DIB_RGB_COLORS) ? sizeof(RGBQUAD) : sizeof(WORD));
    }
}


/***********************************************************************
 *           create_dib_from_bitmap
 *
 *  Allocates a packed DIB and copies the bitmap data into it.
 */
static HGLOBAL create_dib_from_bitmap(HBITMAP hBmp)
{
    BITMAP bmp;
    HDC hdc;
    HGLOBAL hPackedDIB;
    LPBYTE pPackedDIB;
    LPBITMAPINFOHEADER pbmiHeader;
    unsigned int cDataSize, cPackedSize, OffsetBits;
    int nLinesCopied;

    if (!GetObjectW( hBmp, sizeof(bmp), &bmp )) return 0;

    /*
     * A packed DIB contains a BITMAPINFO structure followed immediately by
     * an optional color palette and the pixel data.
     */

    /* Calculate the size of the packed DIB */
    cDataSize = abs( bmp.bmHeight ) * (((bmp.bmWidth * bmp.bmBitsPixel + 31) / 8) & ~3);
    cPackedSize = sizeof(BITMAPINFOHEADER)
                  + ( (bmp.bmBitsPixel <= 8) ? (sizeof(RGBQUAD) * (1 << bmp.bmBitsPixel)) : 0 )
                  + cDataSize;
    /* Get the offset to the bits */
    OffsetBits = cPackedSize - cDataSize;

    /* Allocate the packed DIB */
    TRACE("\tAllocating packed DIB of size %d\n", cPackedSize);
    hPackedDIB = GlobalAlloc( GMEM_FIXED, cPackedSize );
    if ( !hPackedDIB )
    {
        WARN("Could not allocate packed DIB!\n");
        return 0;
    }

    /* A packed DIB starts with a BITMAPINFOHEADER */
    pPackedDIB = GlobalLock(hPackedDIB);
    pbmiHeader = (LPBITMAPINFOHEADER)pPackedDIB;

    /* Init the BITMAPINFOHEADER */
    pbmiHeader->biSize = sizeof(BITMAPINFOHEADER);
    pbmiHeader->biWidth = bmp.bmWidth;
    pbmiHeader->biHeight = bmp.bmHeight;
    pbmiHeader->biPlanes = 1;
    pbmiHeader->biBitCount = bmp.bmBitsPixel;
    pbmiHeader->biCompression = BI_RGB;
    pbmiHeader->biSizeImage = 0;
    pbmiHeader->biXPelsPerMeter = pbmiHeader->biYPelsPerMeter = 0;
    pbmiHeader->biClrUsed = 0;
    pbmiHeader->biClrImportant = 0;

    /* Retrieve the DIB bits from the bitmap and fill in the
     * DIB color table if present */
    hdc = GetDC( 0 );
    nLinesCopied = GetDIBits(hdc,                       /* Handle to device context */
                             hBmp,                      /* Handle to bitmap */
                             0,                         /* First scan line to set in dest bitmap */
                             bmp.bmHeight,              /* Number of scan lines to copy */
                             pPackedDIB + OffsetBits,   /* [out] Address of array for bitmap bits */
                             (LPBITMAPINFO) pbmiHeader, /* [out] Address of BITMAPINFO structure */
                             0);                        /* RGB or palette index */
    GlobalUnlock(hPackedDIB);
    ReleaseDC( 0, hdc );

    /* Cleanup if GetDIBits failed */
    if (nLinesCopied != bmp.bmHeight)
    {
        TRACE("\tGetDIBits returned %d. Actual lines=%d\n", nLinesCopied, bmp.bmHeight);
        GlobalFree(hPackedDIB);
        hPackedDIB = 0;
    }
    return hPackedDIB;
}


/***********************************************************************
 *           uri_to_dos
 *
 *  Converts a text/uri-list URI to DOS filename.
 */
static WCHAR* uri_to_dos(char *encodedURI)
{
    WCHAR *ret = NULL;
    int i;
    int j = 0;
    char *uri = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, strlen(encodedURI) + 1);
    if (uri == NULL)
        return NULL;
    for (i = 0; encodedURI[i]; ++i)
    {
        if (encodedURI[i] == '%')
        {
            if (encodedURI[i+1] && encodedURI[i+2])
            {
                char buffer[3];
                int number;
                buffer[0] = encodedURI[i+1];
                buffer[1] = encodedURI[i+2];
                buffer[2] = '\0';
                sscanf(buffer, "%x", &number);
                uri[j++] = number;
                i += 2;
            }
            else
            {
                WARN("invalid URI encoding in %s\n", debugstr_a(encodedURI));
                HeapFree(GetProcessHeap(), 0, uri);
                return NULL;
            }
        }
        else
            uri[j++] = encodedURI[i];
    }

    /* Read http://www.freedesktop.org/wiki/Draganddropwarts and cry... */
    if (strncmp(uri, "file:/", 6) == 0)
    {
        if (uri[6] == '/')
        {
            if (uri[7] == '/')
            {
                /* file:///path/to/file (nautilus, thunar) */
                ret = wine_get_dos_file_name(&uri[7]);
            }
            else if (uri[7])
            {
                /* file://hostname/path/to/file (X file drag spec) */
                char hostname[256];
                char *path = strchr(&uri[7], '/');
                if (path)
                {
                    *path = '\0';
                    if (strcmp(&uri[7], "localhost") == 0)
                    {
                        *path = '/';
                        ret = wine_get_dos_file_name(path);
                    }
                    else if (gethostname(hostname, sizeof(hostname)) == 0)
                    {
                        if (strcmp(hostname, &uri[7]) == 0)
                        {
                            *path = '/';
                            ret = wine_get_dos_file_name(path);
                        }
                    }
                }
            }
        }
        else if (uri[6])
        {
            /* file:/path/to/file (konqueror) */
            ret = wine_get_dos_file_name(&uri[5]);
        }
    }
    HeapFree(GetProcessHeap(), 0, uri);
    return ret;
}


/**************************************************************************
 *		unicode_text_from_string
 *
 * Convert a string in the specified encoding to CF_UNICODETEXT format.
 */
static HANDLE unicode_text_from_string( UINT codepage, const void *data, size_t size )
{
    DWORD i, j, count;
    WCHAR *strW;

    count = MultiByteToWideChar( codepage, 0, data, size, NULL, 0);

    if (!(strW = GlobalAlloc( GMEM_FIXED, (count * 2 + 1) * sizeof(WCHAR) ))) return 0;

    MultiByteToWideChar( codepage, 0, data, size, strW + count, count );
    for (i = j = 0; i < count; i++)
    {
        if (strW[i + count] == '\n') strW[j++] = '\r';
        strW[j++] = strW[i + count];
    }
    strW[j++] = 0;
    GlobalReAlloc( strW, j * sizeof(WCHAR), GMEM_FIXED );  /* release unused space */
    TRACE( "returning %s\n", debugstr_wn( strW, j - 1 ));
    return strW;
}


/**************************************************************************
 *		import_string
 *
 * Import XA_STRING, converting the string to CF_UNICODETEXT.
 */
static HANDLE import_string( Atom type, const void *data, size_t size )
{
    return unicode_text_from_string( 28591, data, size );
}


/**************************************************************************
 *		import_utf8_string
 *
 * Import XA_UTF8_STRING, converting the string to CF_UNICODETEXT.
 */
static HANDLE import_utf8_string( Atom type, const void *data, size_t size )
{
    return unicode_text_from_string( CP_UTF8, data, size );
}


/**************************************************************************
 *		import_compound_text
 *
 * Import COMPOUND_TEXT to CF_UNICODETEXT.
 */
static HANDLE import_compound_text( Atom type, const void *data, size_t size )
{
    char** srcstr;
    int count;
    HANDLE ret;
    XTextProperty txtprop;

    txtprop.value = (BYTE *)data;
    txtprop.nitems = size;
    txtprop.encoding = x11drv_atom(COMPOUND_TEXT);
    txtprop.format = 8;
    if (XmbTextPropertyToTextList( thread_display(), &txtprop, &srcstr, &count ) != Success) return 0;
    if (!count) return 0;

    ret = unicode_text_from_string( CP_UNIXCP, srcstr[0], strlen(srcstr[0]) + 1 );
    XFreeStringList(srcstr);
    return ret;
}


/**************************************************************************
 *		import_text
 *
 * Import XA_TEXT, converting the string to CF_UNICODETEXT.
 */
static HANDLE import_text( Atom type, const void *data, size_t size )
{
    if (type == XA_STRING) return import_string( type, data, size );
    if (type == x11drv_atom(UTF8_STRING)) return import_utf8_string( type, data, size );
    if (type == x11drv_atom(COMPOUND_TEXT)) return import_compound_text( type, data, size );
    FIXME( "unsupported TEXT type %s\n", debugstr_xatom( type ));
    return 0;
}


/**************************************************************************
 *		import_pixmap
 *
 *  Import XA_PIXMAP, converting the image to CF_DIB.
 */
static HANDLE import_pixmap( Atom type, const void *data, size_t size )
{
    const Pixmap *pPixmap = (const Pixmap *)data;
    BYTE *ptr = NULL;
    XVisualInfo vis = default_visual;
    char buffer[FIELD_OFFSET( BITMAPINFO, bmiColors[256] )];
    BITMAPINFO *info = (BITMAPINFO *)buffer;
    struct gdi_image_bits bits;
    Window root;
    int x,y;               /* Unused */
    unsigned border_width; /* Unused */
    unsigned int depth, width, height;

    /* Get the Pixmap dimensions and bit depth */
    if (!XGetGeometry(gdi_display, *pPixmap, &root, &x, &y, &width, &height,
                      &border_width, &depth)) depth = 0;
    if (!pixmap_formats[depth]) return 0;

    TRACE( "pixmap properties: width=%d, height=%d, depth=%d\n", width, height, depth );

    if (depth != vis.depth) switch (pixmap_formats[depth]->bits_per_pixel)
    {
        case 1:
        case 4:
        case 8:
            break;
        case 16:  /* assume R5G5B5 */
            vis.red_mask   = 0x7c00;
            vis.green_mask = 0x03e0;
            vis.blue_mask  = 0x001f;
            break;
        case 24:  /* assume R8G8B8 */
        case 32:  /* assume A8R8G8B8 */
            vis.red_mask   = 0xff0000;
            vis.green_mask = 0x00ff00;
            vis.blue_mask  = 0x0000ff;
            break;
        default:
            return 0;
    }

    if (!get_pixmap_image( *pPixmap, width, height, &vis, info, &bits ))
    {
        DWORD info_size = bitmap_info_size( info, DIB_RGB_COLORS );

        ptr = GlobalAlloc( GMEM_FIXED, info_size + info->bmiHeader.biSizeImage );
        if (ptr)
        {
            memcpy( ptr, info, info_size );
            memcpy( ptr + info_size, bits.ptr, info->bmiHeader.biSizeImage );
        }
        if (bits.free) bits.free( &bits );
    }
    return ptr;
}


/**************************************************************************
 *		import_image_bmp
 *
 *  Import image/bmp, converting the image to CF_DIB.
 */
static HANDLE import_image_bmp( Atom type, const void *data, size_t size )
{
    HANDLE hClipData = 0;
    const BITMAPFILEHEADER *bfh = data;

    if (size >= sizeof(BITMAPFILEHEADER)+sizeof(BITMAPCOREHEADER) &&
        bfh->bfType == 0x4d42 /* "BM" */)
    {
        const BITMAPINFO *bmi = (const BITMAPINFO *)(bfh + 1);
        HBITMAP hbmp;
        HDC hdc = GetDC(0);

        if ((hbmp = CreateDIBitmap( hdc, &bmi->bmiHeader, CBM_INIT,
                                    (const BYTE *)data + bfh->bfOffBits, bmi, DIB_RGB_COLORS )))
        {
            hClipData = create_dib_from_bitmap( hbmp );
            DeleteObject(hbmp);
        }
        ReleaseDC(0, hdc);
    }
    return hClipData;
}


/**************************************************************************
 *		import_enhmetafile
 */
static HANDLE import_enhmetafile( Atom type, const void *data, size_t size )
{
    return SetEnhMetaFileBits( size, data );
}


/**************************************************************************
 *      import_text_uri_list
 *
 *  Import text/uri-list.
 */
static HANDLE import_text_uri_list( Atom type, const void *data, size_t size )
{
    const char *uriList = data;
    char *uri;
    WCHAR *path;
    WCHAR *out = NULL;
    int total = 0;
    int capacity = 4096;
    int start = 0;
    int end = 0;
    DROPFILES *dropFiles = NULL;

    if (!(out = HeapAlloc(GetProcessHeap(), 0, capacity * sizeof(WCHAR)))) return 0;

    while (end < size)
    {
        while (end < size && uriList[end] != '\r')
            ++end;
        if (end < (size - 1) && uriList[end+1] != '\n')
        {
            WARN("URI list line doesn't end in \\r\\n\n");
            break;
        }

        uri = HeapAlloc(GetProcessHeap(), 0, end - start + 1);
        if (uri == NULL)
            break;
        lstrcpynA(uri, &uriList[start], end - start + 1);
        path = uri_to_dos(uri);
        TRACE("converted URI %s to DOS path %s\n", debugstr_a(uri), debugstr_w(path));
        HeapFree(GetProcessHeap(), 0, uri);

        if (path)
        {
            int pathSize = strlenW(path) + 1;
            if (pathSize > capacity - total)
            {
                capacity = 2*capacity + pathSize;
                out = HeapReAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, out, (capacity + 1)*sizeof(WCHAR));
                if (out == NULL)
                    goto done;
            }
            memcpy(&out[total], path, pathSize * sizeof(WCHAR));
            total += pathSize;
        done:
            HeapFree(GetProcessHeap(), 0, path);
            if (out == NULL)
                break;
        }

        start = end + 2;
        end = start;
    }
    if (out && end >= size)
    {
        if ((dropFiles = GlobalAlloc( GMEM_FIXED, sizeof(DROPFILES) + (total + 1) * sizeof(WCHAR) )))
        {
            dropFiles->pFiles = sizeof(DROPFILES);
            dropFiles->pt.x = 0;
            dropFiles->pt.y = 0;
            dropFiles->fNC = 0;
            dropFiles->fWide = TRUE;
            out[total] = '\0';
            memcpy( (char*)dropFiles + dropFiles->pFiles, out, (total + 1) * sizeof(WCHAR) );
        }
    }
    HeapFree(GetProcessHeap(), 0, out);
    return dropFiles;
}


/**************************************************************************
 *		import_targets
 *
 *  Import TARGETS and mark the corresponding clipboard formats as available.
 */
static HANDLE import_targets( Atom type, const void *data, size_t size )
{
    UINT i, pos, count = size / sizeof(Atom);
    const Atom *properties = data;
    struct clipboard_format *format, **formats;

    if (type != XA_ATOM && type != x11drv_atom(TARGETS)) return 0;

    register_x11_formats( properties, count );

    /* the builtin formats contain duplicates, so allocate some extra space */
    if (!(formats = HeapAlloc( GetProcessHeap(), 0, (count + NB_BUILTIN_FORMATS) * sizeof(*formats ))))
        return 0;

    pos = 0;
    LIST_FOR_EACH_ENTRY( format, &format_list, struct clipboard_format, entry )
    {
        for (i = 0; i < count; i++) if (properties[i] == format->atom) break;
        if (i == count) continue;
        if (format->import && format->id)
        {
            TRACE( "property %s -> format %s\n",
                   debugstr_xatom( properties[i] ), debugstr_format( format->id ));
            SetClipboardData( format->id, 0 );
            formats[pos++] = format;
        }
        else TRACE( "property %s (ignoring)\n", debugstr_xatom( properties[i] ));
    }

    HeapFree( GetProcessHeap(), 0, current_x11_formats );
    current_x11_formats = formats;
    nb_current_x11_formats = pos;
    return (HANDLE)1;
}


/**************************************************************************
 *		import_data
 *
 *  Generic import clipboard data routine.
 */
static HANDLE import_data( Atom type, const void *data, size_t size )
{
    void *ret = GlobalAlloc( GMEM_FIXED, size );

    if (ret) memcpy( ret, data, size );
    return ret;
}


/**************************************************************************
 *		import_selection
 *
 * Import the specified format from the selection and return a global handle to the data.
 */
static HANDLE import_selection( Display *display, Window win, Atom selection,
                                struct clipboard_format *format )
{
    unsigned char *data;
    unsigned long size;
    Atom prop, type;
    HANDLE ret;

    if (!format->import) return 0;

    TRACE( "import %s from %s win %lx to format %s\n",
           debugstr_xatom( format->atom ), debugstr_xatom( selection ),
           win, debugstr_format( format->id ) );

    if ((prop = convert_selection( display, win, selection, format->atom )) == None)
    {
        TRACE( "failed to convert selection\n" );
        return 0;
    }
    if (!X11DRV_CLIPBOARD_ReadProperty( display, win, prop, &type, &data, &size ))
    {
        TRACE( "failed to read property\n" );
        return 0;
    }
    ret = format->import( type, data, size );
    HeapFree( GetProcessHeap(), 0, data );
    return ret;
}


/**************************************************************************
 *      X11DRV_CLIPBOARD_ImportSelection
 *
 *  Import the X selection into the clipboard format registered for the given X target.
 */
void X11DRV_CLIPBOARD_ImportSelection( Display *display, Window win, Atom selection,
                                       Atom *targets, UINT count,
                                       void (*callback)( Atom, UINT, HANDLE ))
{
    UINT i;
    HANDLE handle;
    struct clipboard_format *format;

    register_x11_formats( targets, count );

    for (i = 0; i < count; i++)
    {
        if (!(format = find_x11_format( targets[i] ))) continue;
        if (!format->id) continue;
        if (!(handle = import_selection( display, win, selection, format ))) continue;
        callback( targets[i], format->id, handle );
    }
}


/**************************************************************************
 *		render_format
 */
static void render_format( UINT id )
{
    Display *display = thread_display();
    unsigned int i;
    HANDLE handle = 0;

    if (!current_selection) return;

    for (i = 0; i < nb_current_x11_formats; i++)
    {
        if (current_x11_formats[i]->id != id) continue;
        handle = import_selection( display, import_window, current_selection, current_x11_formats[i] );
        if (handle) SetClipboardData( id, handle );
        break;
    }
}


/**************************************************************************
 *		export_data
 *
 *  Generic export clipboard data routine.
 */
static BOOL export_data( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    void *ptr = GlobalLock( handle );

    if (!ptr) return FALSE;
    put_property( display, win, prop, target, 8, ptr, GlobalSize( handle ));
    GlobalUnlock( handle );
    return TRUE;
}


/**************************************************************************
 *		string_from_unicode_text
 *
 * Convert CF_UNICODETEXT data to a string in the specified codepage.
 */
static char *string_from_unicode_text( UINT codepage, HANDLE handle, UINT *size )
{
    UINT i, j;
    char *str;
    WCHAR *strW = GlobalLock( handle );
    UINT lenW = GlobalSize( handle ) / sizeof(WCHAR);
    DWORD len = WideCharToMultiByte( codepage, 0, strW, lenW, NULL, 0, NULL, NULL );

    if ((str = HeapAlloc( GetProcessHeap(), 0, len )))
    {
        WideCharToMultiByte( codepage, 0, strW, lenW, str, len, NULL, NULL);
        GlobalUnlock( handle );

        /* remove carriage returns */
        for (i = j = 0; i < len; i++)
        {
            if (str[i] == '\r' && (i == len - 1 || str[i + 1] == '\n')) continue;
            str[j++] = str[i];
        }
        if (j && !str[j - 1]) j--;  /* remove trailing null */
        *size = j;
        TRACE( "returning %s\n", debugstr_an( str, j ));
    }
    GlobalUnlock( handle );
    return str;
}


/**************************************************************************
 *		export_string
 *
 * Export CF_UNICODETEXT converting the string to XA_STRING.
 */
static BOOL export_string( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    UINT size;
    char *text = string_from_unicode_text( 28591, handle, &size );

    if (!text) return FALSE;
    put_property( display, win, prop, target, 8, text, size );
    HeapFree( GetProcessHeap(), 0, text );
    GlobalUnlock( handle );
    return TRUE;
}


/**************************************************************************
 *		export_utf8_string
 *
 *  Export CF_UNICODE converting the string to UTF8.
 */
static BOOL export_utf8_string( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    UINT size;
    char *text = string_from_unicode_text( CP_UTF8, handle, &size );

    if (!text) return FALSE;
    put_property( display, win, prop, target, 8, text, size );
    HeapFree( GetProcessHeap(), 0, text );
    GlobalUnlock( handle );
    return TRUE;
}


/**************************************************************************
 *		export_text
 *
 *  Export CF_UNICODE to the polymorphic TEXT type, using UTF8.
 */
static BOOL export_text( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    return export_utf8_string( display, win, prop, x11drv_atom(UTF8_STRING), handle );
}


/**************************************************************************
 *		export_compound_text
 *
 *  Export CF_UNICODE to COMPOUND_TEXT
 */
static BOOL export_compound_text( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    XTextProperty textprop;
    XICCEncodingStyle style;
    UINT size;
    char *text = string_from_unicode_text( CP_UNIXCP, handle, &size );

    if (!text) return FALSE;
    if (target == x11drv_atom(COMPOUND_TEXT))
        style = XCompoundTextStyle;
    else
        style = XStdICCTextStyle;

    /* Update the X property */
    if (XmbTextListToTextProperty( display, &text, 1, style, &textprop ) == Success)
    {
        XSetTextProperty( display, win, &textprop, prop );
        XFree( textprop.value );
    }

    HeapFree( GetProcessHeap(), 0, text );
    return TRUE;
}


/**************************************************************************
 *		export_pixmap
 *
 *  Export CF_DIB to XA_PIXMAP.
 */
static BOOL export_pixmap( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    Pixmap pixmap;
    BITMAPINFO *pbmi;
    struct gdi_image_bits bits;

    pbmi = GlobalLock( handle );
    bits.ptr = (LPBYTE)pbmi + bitmap_info_size( pbmi, DIB_RGB_COLORS );
    bits.free = NULL;
    bits.is_copy = FALSE;
    pixmap = create_pixmap_from_image( 0, &default_visual, pbmi, &bits, DIB_RGB_COLORS );
    GlobalUnlock( handle );

    put_property( display, win, prop, target, 32, &pixmap, 1 );
    /* FIXME: free the pixmap when the property is deleted */
    return TRUE;
}


/**************************************************************************
 *		export_image_bmp
 *
 *  Export CF_DIB to image/bmp.
 */
static BOOL export_image_bmp( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    LPBYTE dibdata = GlobalLock( handle );
    UINT bmpsize;
    BITMAPFILEHEADER *bfh;

    bmpsize = sizeof(BITMAPFILEHEADER) + GlobalSize( handle );
    bfh = HeapAlloc( GetProcessHeap(), 0, bmpsize );
    if (bfh)
    {
        /* bitmap file header */
        bfh->bfType = 0x4d42; /* "BM" */
        bfh->bfSize = bmpsize;
        bfh->bfReserved1 = 0;
        bfh->bfReserved2 = 0;
        bfh->bfOffBits = sizeof(BITMAPFILEHEADER) + bitmap_info_size((BITMAPINFO*)dibdata, DIB_RGB_COLORS);

        /* rest of bitmap is the same as the packed dib */
        memcpy(bfh+1, dibdata, bmpsize-sizeof(BITMAPFILEHEADER));
    }
    GlobalUnlock( handle );
    put_property( display, win, prop, target, 8, bfh, bmpsize );
    HeapFree( GetProcessHeap(), 0, bfh );
    return TRUE;
}


/**************************************************************************
 *		export_enhmetafile
 *
 *  Export EnhMetaFile.
 */
static BOOL export_enhmetafile( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    unsigned int size;
    void *ptr;

    if (!(size = GetEnhMetaFileBits( handle, 0, NULL ))) return FALSE;
    if (!(ptr = HeapAlloc( GetProcessHeap(), 0, size ))) return FALSE;

    GetEnhMetaFileBits( handle, size, ptr );
    put_property( display, win, prop, target, 8, ptr, size );
    HeapFree( GetProcessHeap(), 0, ptr );
    return TRUE;
}


/**************************************************************************
 *		get_html_description_field
 *
 *  Find the value of a field in an HTML Format description.
 */
static LPCSTR get_html_description_field(LPCSTR data, LPCSTR keyword)
{
    LPCSTR pos=data;

    while (pos && *pos && *pos != '<')
    {
        if (memcmp(pos, keyword, strlen(keyword)) == 0)
            return pos+strlen(keyword);

        pos = strchr(pos, '\n');
        if (pos) pos++;
    }

    return NULL;
}


/**************************************************************************
 *		export_text_html
 *
 *  Export HTML Format to text/html.
 *
 * FIXME: We should attempt to add an <a base> tag and convert windows paths.
 */
static BOOL export_text_html( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    LPCSTR data, field_value;
    UINT fragmentstart, fragmentend;

    data = GlobalLock( handle );

    /* read the important fields */
    field_value = get_html_description_field(data, "StartFragment:");
    if (!field_value)
    {
        ERR("Couldn't find StartFragment value\n");
        goto failed;
    }
    fragmentstart = atoi(field_value);

    field_value = get_html_description_field(data, "EndFragment:");
    if (!field_value)
    {
        ERR("Couldn't find EndFragment value\n");
        goto failed;
    }
    fragmentend = atoi(field_value);

    /* export only the fragment */
    put_property( display, win, prop, target, 8, &data[fragmentstart], fragmentend - fragmentstart );
    GlobalUnlock( handle );
    return TRUE;

failed:
    GlobalUnlock( handle );
    return FALSE;
}


/**************************************************************************
 *      export_hdrop
 *
 *  Export CF_HDROP format to text/uri-list.
 */
static BOOL export_hdrop( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    UINT i;
    UINT numFiles;
    char *textUriList;
    UINT textUriListSize = 32;
    UINT next = 0;

    textUriList = HeapAlloc( GetProcessHeap(), 0, textUriListSize );
    if (!textUriList) return FALSE;
    numFiles = DragQueryFileW( handle, 0xFFFFFFFF, NULL, 0 );
    for (i = 0; i < numFiles; i++)
    {
        UINT dosFilenameSize;
        WCHAR *dosFilename = NULL;
        char *unixFilename = NULL;
        UINT uriSize;
        UINT u;

        dosFilenameSize = 1 + DragQueryFileW( handle, i, NULL, 0 );
        dosFilename = HeapAlloc(GetProcessHeap(), 0, dosFilenameSize*sizeof(WCHAR));
        if (dosFilename == NULL) goto failed;
        DragQueryFileW( handle, i, dosFilename, dosFilenameSize );
        unixFilename = wine_get_unix_file_name(dosFilename);
        HeapFree(GetProcessHeap(), 0, dosFilename);
        if (unixFilename == NULL) goto failed;
        uriSize = 8 + /* file:/// */
                3 * (lstrlenA(unixFilename) - 1) + /* "%xy" per char except first '/' */
                2; /* \r\n */
        if ((next + uriSize) > textUriListSize)
        {
            UINT biggerSize = max( 2 * textUriListSize, next + uriSize );
            void *bigger = HeapReAlloc( GetProcessHeap(), 0, textUriList, biggerSize );
            if (bigger)
            {
                textUriList = bigger;
                textUriListSize = biggerSize;
            }
            else
            {
                HeapFree(GetProcessHeap(), 0, unixFilename);
                goto failed;
            }
        }
        lstrcpyA(&textUriList[next], "file:///");
        next += 8;
        /* URL encode everything - unnecessary, but easier/lighter than linking in shlwapi, and can't hurt */
        for (u = 1; unixFilename[u]; u++)
        {
            static const char hex_table[] = "0123456789abcdef";
            textUriList[next++] = '%';
            textUriList[next++] = hex_table[unixFilename[u] >> 4];
            textUriList[next++] = hex_table[unixFilename[u] & 0xf];
        }
        textUriList[next++] = '\r';
        textUriList[next++] = '\n';
        HeapFree(GetProcessHeap(), 0, unixFilename);
    }
    put_property( display, win, prop, target, 8, textUriList, next );
    HeapFree( GetProcessHeap(), 0, textUriList );
    return TRUE;

failed:
    HeapFree( GetProcessHeap(), 0, textUriList );
    return FALSE;
}


/***********************************************************************
 *           get_clipboard_formats
 *
 * Return a list of all formats currently available on the Win32 clipboard.
 * Helper for export_targets.
 */
static UINT *get_clipboard_formats( UINT *size )
{
    UINT *ids;

    *size = 256;
    for (;;)
    {
        if (!(ids = HeapAlloc( GetProcessHeap(), 0, *size * sizeof(*ids) ))) return NULL;
        if (GetUpdatedClipboardFormats( ids, *size, size )) break;
        HeapFree( GetProcessHeap(), 0, ids );
        if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) return NULL;
    }
    register_win32_formats( ids, *size );
    return ids;
}


/***********************************************************************
 *           is_format_available
 *
 * Check if a clipboard format is included in the list.
 * Helper for export_targets.
 */
static BOOL is_format_available( UINT format, const UINT *ids, unsigned int count )
{
    while (count--) if (*ids++ == format) return TRUE;
    return FALSE;
}


/***********************************************************************
 *           export_targets
 *
 *  Service a TARGETS selection request event
 */
static BOOL export_targets( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    struct clipboard_format *format;
    UINT pos, count, *formats;
    Atom *targets;

    if (!(formats = get_clipboard_formats( &count ))) return FALSE;

    /* the builtin formats contain duplicates, so allocate some extra space */
    if (!(targets = HeapAlloc( GetProcessHeap(), 0, (count + NB_BUILTIN_FORMATS) * sizeof(*targets) )))
    {
        HeapFree( GetProcessHeap(), 0, formats );
        return FALSE;
    }

    pos = 0;
    LIST_FOR_EACH_ENTRY( format, &format_list, struct clipboard_format, entry )
    {
        if (!format->export) continue;
        /* formats with id==0 are always exported */
        if (format->id && !is_format_available( format->id, formats, count )) continue;
        TRACE( "%d: %s -> %s\n", pos, debugstr_format( format->id ), debugstr_xatom( format->atom ));
        targets[pos++] = format->atom;
    }

    put_property( display, win, prop, XA_ATOM, 32, targets, pos );
    HeapFree( GetProcessHeap(), 0, targets );
    HeapFree( GetProcessHeap(), 0, formats );
    return TRUE;
}


/**************************************************************************
 *      export_selection
 *
 * Export selection data, depending on the target type.
 */
static BOOL export_selection( Display *display, Window win, Atom prop, Atom target )
{
    struct clipboard_format *format;
    HANDLE handle = 0;
    BOOL open = FALSE, ret = FALSE;

    LIST_FOR_EACH_ENTRY( format, &format_list, struct clipboard_format, entry )
    {
        if (format->atom != target) continue;
        if (!format->export) continue;
        if (!format->id)
        {
            TRACE( "win %lx prop %s target %s\n", win, debugstr_xatom( prop ), debugstr_xatom( target ));
            ret = format->export( display, win, prop, target, 0 );
            break;
        }
        if (!open && !(open = OpenClipboard( clipboard_hwnd )))
        {
            ERR( "failed to open clipboard for %s\n", debugstr_xatom( target ));
            return FALSE;
        }
        if ((handle = GetClipboardData( format->id )))
        {
            TRACE( "win %lx prop %s target %s exporting %s %p\n",
                   win, debugstr_xatom( prop ), debugstr_xatom( target ),
                   debugstr_format( format->id ), handle );

            ret = format->export( display, win, prop, target, handle );
            break;
        }
        /* keep looking for another Win32 format mapping to the same target */
    }
    if (open) CloseClipboard();
    return ret;
}


/***********************************************************************
 *           export_multiple
 *
 *  Service a MULTIPLE selection request event
 *  prop contains a list of (target,property) atom pairs.
 *  The first atom names a target and the second names a property.
 *  The effect is as if we have received a sequence of SelectionRequest events
 *  (one for each atom pair) except that:
 *  1. We reply with a SelectionNotify only when all the requested conversions
 *  have been performed.
 *  2. If we fail to convert the target named by an atom in the MULTIPLE property,
 *  we replace the atom in the property by None.
 */
static BOOL export_multiple( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    Atom atype;
    int aformat;
    Atom *list;
    unsigned long i, count, failed, remain;

    /* Read the MULTIPLE property contents. This should contain a list of
     * (target,property) atom pairs.
     */
    if (XGetWindowProperty( display, win, prop, 0, 0x3FFF, False, AnyPropertyType, &atype, &aformat,
                            &count, &remain, (unsigned char**)&list ))
        return FALSE;

    TRACE( "type %s format %d count %ld remain %ld\n",
           debugstr_xatom( atype ), aformat, count, remain );

    /*
     * Make sure we got what we expect.
     * NOTE: According to the X-ICCCM Version 2.0 documentation the property sent
     * in a MULTIPLE selection request should be of type ATOM_PAIR.
     * However some X apps(such as XPaint) are not compliant with this and return
     * a user defined atom in atype when XGetWindowProperty is called.
     * The data *is* an atom pair but is not denoted as such.
     */
    if (aformat == 32 /* atype == xAtomPair */ )
    {
        for (i = failed = 0; i < count; i += 2)
        {
            if (list[i+1] == None) continue;
            if (export_selection( display, win, list[i + 1], list[i] )) continue;
            failed++;
            list[i + 1] = None;
        }
        if (failed) put_property( display, win, prop, atype, 32, list, count );
    }
    XFree( list );
    return TRUE;
}


/***********************************************************************
 *           export_timestamp
 *
 * Export the timestamp that was used to acquire the selection
 */
static BOOL export_timestamp( Display *display, Window win, Atom prop, Atom target, HANDLE handle )
{
    Time time = CurrentTime;  /* FIXME */
    put_property( display, win, prop, XA_INTEGER, 32, &time, 1 );
    return TRUE;
}


/**************************************************************************
 *		X11DRV_CLIPBOARD_GetProperty
 *  Gets type, data and size.
 */
static BOOL X11DRV_CLIPBOARD_GetProperty(Display *display, Window w, Atom prop,
    Atom *atype, unsigned char** data, unsigned long* datasize)
{
    int aformat;
    unsigned long pos = 0, nitems, remain, count;
    unsigned char *val = NULL, *buffer;

    for (;;)
    {
        if (XGetWindowProperty(display, w, prop, pos, INT_MAX / 4, False,
                               AnyPropertyType, atype, &aformat, &nitems, &remain, &buffer))
        {
            WARN("Failed to read property\n");
            HeapFree( GetProcessHeap(), 0, val );
            return FALSE;
        }

        count = get_property_size( aformat, nitems );
        if (!val) *data = HeapAlloc( GetProcessHeap(), 0, pos * sizeof(int) + count + 1 );
        else *data = HeapReAlloc( GetProcessHeap(), 0, val, pos * sizeof(int) + count + 1 );

        if (!*data)
        {
            XFree( buffer );
            HeapFree( GetProcessHeap(), 0, val );
            return FALSE;
        }
        val = *data;
        memcpy( (int *)val + pos, buffer, count );
        XFree( buffer );
        if (!remain)
        {
            *datasize = pos * sizeof(int) + count;
            val[*datasize] = 0;
            break;
        }
        pos += count / sizeof(int);
    }

    TRACE( "got property %s type %s format %u len %lu from window %lx\n",
           debugstr_xatom( prop ), debugstr_xatom( *atype ), aformat, *datasize, w );

    /* Delete the property on the window now that we are done
     * This will send a PropertyNotify event to the selection owner. */
    XDeleteProperty(display, w, prop);
    return TRUE;
}


struct clipboard_data_packet {
    struct list entry;
    unsigned long size;
    unsigned char *data;
};

/**************************************************************************
 *		X11DRV_CLIPBOARD_ReadProperty
 *  Reads the contents of the X selection property.
 */
static BOOL X11DRV_CLIPBOARD_ReadProperty( Display *display, Window w, Atom prop,
                                           Atom *type, unsigned char** data, unsigned long* datasize )
{
    XEvent xe;

    if (prop == None)
        return FALSE;

    while (XCheckTypedWindowEvent(display, w, PropertyNotify, &xe))
        ;

    if (!X11DRV_CLIPBOARD_GetProperty(display, w, prop, type, data, datasize))
        return FALSE;

    if (*type == x11drv_atom(INCR))
    {
        unsigned char *buf;
        unsigned long bufsize = 0;
        struct list packets;
        struct clipboard_data_packet *packet, *packet2;
        BOOL res;

        HeapFree(GetProcessHeap(), 0, *data);
        *data = NULL;

        list_init(&packets);

        for (;;)
        {
            int i;
            unsigned char *prop_data;
            unsigned long prop_size;

            /* Wait until PropertyNotify is received */
            for (i = 0; i < SELECTION_RETRIES; i++)
            {
                Bool res;

                res = XCheckTypedWindowEvent(display, w, PropertyNotify, &xe);
                if (res && xe.xproperty.atom == prop &&
                    xe.xproperty.state == PropertyNewValue)
                    break;
                usleep(SELECTION_WAIT);
            }

            if (i >= SELECTION_RETRIES ||
                !X11DRV_CLIPBOARD_GetProperty(display, w, prop, type, &prop_data, &prop_size))
            {
                res = FALSE;
                break;
            }

            /* Retrieved entire data. */
            if (prop_size == 0)
            {
                HeapFree(GetProcessHeap(), 0, prop_data);
                res = TRUE;
                break;
            }

            packet = HeapAlloc(GetProcessHeap(), 0, sizeof(*packet));
            if (!packet)
            {
                HeapFree(GetProcessHeap(), 0, prop_data);
                res = FALSE;
                break;
            }

            packet->size = prop_size;
            packet->data = prop_data;
            list_add_tail(&packets, &packet->entry);
            bufsize += prop_size;
        }

        if (res)
        {
            buf = HeapAlloc(GetProcessHeap(), 0, bufsize + 1);
            if (buf)
            {
                unsigned long bytes_copied = 0;
                *datasize = bufsize;
                LIST_FOR_EACH_ENTRY( packet, &packets, struct clipboard_data_packet, entry)
                {
                    memcpy(&buf[bytes_copied], packet->data, packet->size);
                    bytes_copied += packet->size;
                }
                buf[bufsize] = 0;
                *data = buf;
            }
            else
                res = FALSE;
        }

        LIST_FOR_EACH_ENTRY_SAFE( packet, packet2, &packets, struct clipboard_data_packet, entry)
        {
            HeapFree(GetProcessHeap(), 0, packet->data);
            HeapFree(GetProcessHeap(), 0, packet);
        }

        return res;
    }

    return TRUE;
}


/**************************************************************************
 *		acquire_selection
 *
 * Acquire the X11 selection when the Win32 clipboard has changed.
 */
static void acquire_selection( Display *display )
{
    if (selection_window) XDestroyWindow( display, selection_window );

    selection_window = XCreateWindow( display, root_window, 0, 0, 1, 1, 0, CopyFromParent,
                                      InputOutput, CopyFromParent, 0, NULL );
    if (!selection_window) return;

    XSetSelectionOwner( display, x11drv_atom(CLIPBOARD), selection_window, CurrentTime );
    if (use_primary_selection) XSetSelectionOwner( display, XA_PRIMARY, selection_window, CurrentTime );
    TRACE( "win %lx\n", selection_window );
}


/**************************************************************************
 *		release_selection
 *
 * Release the X11 selection when some other X11 app has grabbed it.
 */
static void release_selection( Display *display, Time time )
{
    assert( selection_window );

    TRACE( "win %lx\n", selection_window );

    /* release PRIMARY if we still own it */
    if (use_primary_selection && XGetSelectionOwner( display, XA_PRIMARY ) == selection_window)
        XSetSelectionOwner( display, XA_PRIMARY, None, time );

    XDestroyWindow( display, selection_window );
    selection_window = 0;
}


/**************************************************************************
 *		request_selection_contents
 *
 * Retrieve the contents of the X11 selection when it's owned by an X11 app.
 */
static void request_selection_contents( Display *display )
{
    struct clipboard_format *targets = find_x11_format( x11drv_atom(TARGETS) );
    struct clipboard_format *string = find_x11_format( XA_STRING );

    assert( targets );
    assert( string );

    current_selection = 0;
    if (use_primary_selection && XGetSelectionOwner( display, XA_PRIMARY ))
    {
        if (import_selection( display, import_window, XA_PRIMARY, targets ))
            current_selection = XA_PRIMARY;
        else
            import_selection( display, import_window, XA_PRIMARY, string );
    }
    else if (XGetSelectionOwner( display, x11drv_atom(CLIPBOARD) ))
    {
        if (import_selection( display, import_window, x11drv_atom(CLIPBOARD), targets ))
            current_selection = x11drv_atom(CLIPBOARD);
        else
            import_selection( display, import_window, x11drv_atom(CLIPBOARD), string );
    }
}


/**************************************************************************
 *		grab_win32_clipboard
 *
 * Grab the Win32 clipboard when an X11 app has grabbed the X11 selection,
 * and fill it with the selection contents.
 */
static BOOL grab_win32_clipboard( Display *display )
{
    if (!OpenClipboard( clipboard_hwnd )) return FALSE;
    EmptyClipboard();
    is_clipboard_owner = TRUE;
    last_clipboard_update = GetTickCount64();
    request_selection_contents( display );
    CloseClipboard();
    return TRUE;
}


/**************************************************************************
 *		update_clipboard
 *
 * Periodically update the clipboard while the selection is owned by an X11 app.
 */
BOOL update_clipboard( HWND hwnd )
{
    if (hwnd != clipboard_hwnd) return TRUE;
    if (!is_clipboard_owner) return TRUE;
    if (GetTickCount64() - last_clipboard_update <= SELECTION_UPDATE_DELAY) return TRUE;
    return grab_win32_clipboard( thread_display() );
}


/**************************************************************************
 *		clipboard_wndproc
 *
 * Window procedure for the clipboard manager.
 */
static LRESULT CALLBACK clipboard_wndproc( HWND hwnd, UINT msg, WPARAM wp, LPARAM lp )
{
    switch (msg)
    {
    case WM_NCCREATE:
        return TRUE;
    case WM_CLIPBOARDUPDATE:
        if (is_clipboard_owner) break;  /* ignore our own changes */
        acquire_selection( thread_init_display() );
        break;
    case WM_RENDERFORMAT:
        render_format( wp );
        break;
    case WM_DESTROYCLIPBOARD:
        TRACE( "WM_DESTROYCLIPBOARD: lost ownership\n" );
        is_clipboard_owner = FALSE;
        break;
    }
    return DefWindowProcW( hwnd, msg, wp, lp );
}


/**************************************************************************
 *		wait_clipboard_mutex
 *
 * Make sure that there's only one clipboard thread per window station.
 */
static BOOL wait_clipboard_mutex(void)
{
    static const WCHAR prefix[] = {'_','_','w','i','n','e','_','c','l','i','p','b','o','a','r','d','_'};
    WCHAR buffer[MAX_PATH + sizeof(prefix) / sizeof(WCHAR)];
    HANDLE mutex;

    memcpy( buffer, prefix, sizeof(prefix) );
    if (!GetUserObjectInformationW( GetProcessWindowStation(), UOI_NAME,
                                    buffer + sizeof(prefix) / sizeof(WCHAR),
                                    sizeof(buffer) - sizeof(prefix), NULL ))
    {
        ERR( "failed to get winstation name\n" );
        return FALSE;
    }
    mutex = CreateMutexW( NULL, TRUE, buffer );
    if (GetLastError() == ERROR_ALREADY_EXISTS)
    {
        TRACE( "waiting for mutex %s\n", debugstr_w( buffer ));
        WaitForSingleObject( mutex, INFINITE );
    }
    return TRUE;
}


/**************************************************************************
 *		clipboard_thread
 *
 * Thread running inside the desktop process to manage the clipboard
 */
static DWORD WINAPI clipboard_thread( void *arg )
{
    static const WCHAR clipboard_classname[] = {'_','_','w','i','n','e','_','c','l','i','p','b','o','a','r','d','_','m','a','n','a','g','e','r',0};
    XSetWindowAttributes attr;
    WNDCLASSW class;
    MSG msg;

    if (!wait_clipboard_mutex()) return 0;

    clipboard_display = thread_init_display();
    attr.event_mask = PropertyChangeMask;
    import_window = XCreateWindow( clipboard_display, root_window, 0, 0, 1, 1, 0, CopyFromParent,
                                   InputOutput, CopyFromParent, CWEventMask, &attr );
    if (!import_window)
    {
        ERR( "failed to create import window\n" );
        return 0;
    }

    memset( &class, 0, sizeof(class) );
    class.lpfnWndProc   = clipboard_wndproc;
    class.lpszClassName = clipboard_classname;

    if (!RegisterClassW( &class ) && GetLastError() != ERROR_CLASS_ALREADY_EXISTS)
    {
        ERR( "could not register clipboard window class err %u\n", GetLastError() );
        return 0;
    }
    if (!(clipboard_hwnd = CreateWindowW( clipboard_classname, NULL, 0, 0, 0, 0, 0,
                                          HWND_MESSAGE, 0, 0, NULL )))
    {
        ERR( "failed to create clipboard window err %u\n", GetLastError() );
        return 0;
    }

    clipboard_thread_id = GetCurrentThreadId();
    AddClipboardFormatListener( clipboard_hwnd );
    register_builtin_formats();
    grab_win32_clipboard( clipboard_display );

    TRACE( "clipboard thread %04x running\n", GetCurrentThreadId() );
    while (GetMessageW( &msg, 0, 0, 0 )) DispatchMessageW( &msg );
    return 0;
}


/**************************************************************************
 *		X11DRV_UpdateClipboard
 */
void CDECL X11DRV_UpdateClipboard(void)
{
    static ULONG last_update;
    ULONG now;
    DWORD_PTR ret;

    if (GetCurrentThreadId() == clipboard_thread_id) return;
    now = GetTickCount();
    if ((int)(now - last_update) <= SELECTION_UPDATE_DELAY) return;
    if (SendMessageTimeoutW( GetClipboardOwner(), WM_X11DRV_UPDATE_CLIPBOARD, 0, 0,
                             SMTO_ABORTIFHUNG, 5000, &ret ) && ret)
        last_update = now;
}


/***********************************************************************
 *           X11DRV_HandleSelectionRequest
 */
BOOL X11DRV_SelectionRequest( HWND hwnd, XEvent *xev )
{
    XSelectionRequestEvent *event = &xev->xselectionrequest;
    Display *display = event->display;
    XEvent result;
    Atom rprop = None;

    TRACE( "got request on %lx for selection %s target %s win %lx prop %s\n",
           event->owner, debugstr_xatom( event->selection ), debugstr_xatom( event->target ),
           event->requestor, debugstr_xatom( event->property ));

    if (event->owner != selection_window) goto done;
    if ((event->selection != x11drv_atom(CLIPBOARD)) &&
        (!use_primary_selection || event->selection != XA_PRIMARY)) goto done;

    /* If the specified property is None the requestor is an obsolete client.
     * We support these by using the specified target atom as the reply property.
     */
    rprop = event->property;
    if( rprop == None )
        rprop = event->target;

    if (!export_selection( display, event->requestor, rprop, event->target ))
        rprop = None;  /* report failure to client */

done:
    result.xselection.type = SelectionNotify;
    result.xselection.display = display;
    result.xselection.requestor = event->requestor;
    result.xselection.selection = event->selection;
    result.xselection.property = rprop;
    result.xselection.target = event->target;
    result.xselection.time = event->time;
    TRACE( "sending SelectionNotify for %s to %lx\n", debugstr_xatom( rprop ), event->requestor );
    XSendEvent( display, event->requestor, False, NoEventMask, &result );
    return FALSE;
}


/***********************************************************************
 *           X11DRV_SelectionClear
 */
BOOL X11DRV_SelectionClear( HWND hwnd, XEvent *xev )
{
    XSelectionClearEvent *event = &xev->xselectionclear;

    if (event->window != selection_window) return FALSE;
    if (event->selection != x11drv_atom(CLIPBOARD)) return FALSE;

    release_selection( event->display, event->time );
    grab_win32_clipboard( event->display );
    return FALSE;
}


/**************************************************************************
 *		X11DRV_InitClipboard
 */
void X11DRV_InitClipboard(void)
{
    DWORD id;
    HANDLE handle = CreateThread( NULL, 0, clipboard_thread, NULL, 0, &id );

    if (handle) CloseHandle( handle );
    else ERR( "failed to create clipboard thread\n" );
}
