/* $Xorg: xprop.c,v 1.6 2001/02/09 02:05:56 xorgcvs Exp $ */
/*

Copyright 1990, 1998  The Open Group
Copyright (c) 2000  The XFree86 Project, Inc.

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.
  
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from The Open Group.

*/
/* $XFree86: xc/programs/xprop/xprop.c,v 1.15 2003/09/24 02:43:38 dawes Exp $ */


#include <X11/Xlib.h>
#include <X11/Xos.h>
#include <X11/Xfuncs.h>
#include <X11/Xutil.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#ifdef HAS_WCHAR_H
#include <wchar.h>
#endif
#ifdef HAS_WCTYPE_H
#include <wctype.h>
#endif
#include <locale.h>

#ifndef HAS_WCTYPE_H
#define iswprint(x) isprint(x)
#endif

#include <X11/Xatom.h>
#include <X11/Xmu/WinUtil.h>

#include "dsimple.h"

#define MAXSTR 10000
#define MAXELEMENTS 64

#ifndef min
#define min(a,b)  ((a) < (b) ? (a) : (b))
#endif

/* isprint() in "C" locale */
#define c_isprint(c) ((c) >= 0x20 && (c) < 0x7f)

/*
 *
 * The Thunk Manager - routines to create, add to, and free thunk lists
 *
 */

typedef struct {
  int thunk_count;
  const char *propname;
  long value;
  Atom extra_encoding;
  const char *extra_value;
  const char *format;
  const char *dformat;
} thunk;

static thunk *
Create_Thunk_List (void)
{
    thunk *tptr;

    tptr = (thunk *) Malloc(sizeof(thunk));

    tptr->thunk_count = 0;

    return tptr;
}

#ifdef notused
static void
Free_Thunk_List (thunk *list)
{
    free(list);
}
#endif

static thunk *
Add_Thunk (thunk *list, thunk t)
{
    int i;

    i = list->thunk_count;

    list = (thunk *) realloc(list, (i+1)*sizeof(thunk));
    if (!list)
	Fatal_Error("Out of memory!");

    list[i++] = t;
    list->thunk_count = i;

    return list;
}

/*
 * Misc. routines
 */

static char *
Copy_String (const char *string)
{
    char *new;
    int length;

    length = strlen(string) + 1;

    new = (char *) Malloc(length);
    memcpy(new, string, length);

    return new;
}

static int
Read_Char (FILE *stream)
{
    int c;

    c = getc(stream);
    if (c == EOF)
	Fatal_Error("Bad format file: Unexpected EOF.");
    return c;
}

static void
Read_White_Space (FILE *stream)
{
    int c;

    while ((c = getc(stream)) == ' ' || c == '\n' || c == '\t');
    ungetc(c, stream);
}

static char _large_buffer[MAXSTR+10];

static char *
Read_Quoted (FILE *stream)
{
    char *ptr;
    int c, length;

    Read_White_Space(stream);
    if (Read_Char(stream)!='\'')
	Fatal_Error("Bad format file format: missing dformat.");

    ptr = _large_buffer; length = MAXSTR;
    for (;;) {
	if (length < 0)
	    Fatal_Error("Bad format file format: dformat too long.");
	c = Read_Char(stream);
	if (c == (int) '\'')
	    break;
	ptr++[0] = c; length--;
	if (c == (int) '\\') {
	    c = Read_Char(stream);
	    if (c == '\n') {
		ptr--; length++;
	    } else
		ptr++[0] = c; length--;
	}
    }
    ptr++[0] = '\0';

    return Copy_String(_large_buffer);
}

/*
 *
 * Parsing Routines: a group of routines to parse strings into values
 *
 * Routines: Parse_Atom, Scan_Long, Skip_Past_Right_Paren, Scan_Octal
 *
 * Routines of the form Parse_XXX take a string which is parsed to a value.
 * Routines of the form Scan_XXX take a string, parse the beginning to a value,
 * and return the rest of the string.  The value is returned via. the last
 * parameter.  All numeric values are longs!
 *
 */

static const char *
Skip_Digits (const char *string)
{
    while (isdigit((unsigned char) string[0])) string++;
    return string;
}

static const char *
Scan_Long (const char *string, long *value)
{
    if (!isdigit((unsigned char) *string))
	Fatal_Error("Bad number: %s.", string);

    *value = atol(string);
    return Skip_Digits(string);
}

static const char *
Scan_Octal (const char *string, unsigned long *value)
{
    if (sscanf(string, "%lo", value)!=1)
	Fatal_Error("Bad octal number: %s.", string);
    return Skip_Digits(string);
}

static Atom
Parse_Atom (const char *name, int only_if_exists)
{
    /* may return None = 0 */
    return XInternAtom(dpy, name, only_if_exists);
}

static const char *
Skip_Past_Right_Paren (const char *string)
{
    char c;
    int nesting = 0;

    while (c = string++[0], c != ')' || nesting)
	switch (c) {
	  case '\0':
	    Fatal_Error("Missing ')'.");
	  case '(':
	    nesting++;
	    break;
	  case ')':
	    nesting--;
	    break;
	  case '\\':
	    string++;
	    break;
	}
    return string;
}

/*
 *
 * Atom to format, dformat mapping Manager
 *
 */

#define D_FORMAT "0x"              /* Default format for properties */
#define D_DFORMAT " = $0+\n"       /* Default display pattern for properties */

static thunk *_property_formats = NULL;   /* Holds mapping */

static void
Apply_Default_Formats (const char **format, const char **dformat)
{
    if (!*format)
	*format = D_FORMAT;
    if (!*dformat)
	*dformat = D_DFORMAT;
}

static void
Lookup_Formats (Atom atom, const char **format, const char **dformat)
{
    int i;

    if (_property_formats)
	for (i = _property_formats->thunk_count-1; i >= 0; i--)
	    if (_property_formats[i].value == atom) {
		if (!*format)
		    *format = _property_formats[i].format;
		if (!*dformat)
		    *dformat = _property_formats[i].dformat;
		break;
	    }
}

static void
Add_Mapping (Atom atom, const char *format, const char *dformat)
{
    thunk t;

    if (!_property_formats)
	_property_formats = Create_Thunk_List();

    t.value = atom;
    t.format = format;
    t.dformat = dformat;

    _property_formats = Add_Thunk(_property_formats, t);
}

/*
 *
 * Setup_Mapping: Routine to setup default atom to format, dformat mapping:
 * 
 */

typedef struct _propertyRec {
    const char *	name;
    Atom		atom;
    const char *	format;
    const char *	dformat;
} propertyRec;

#define ARC_DFORMAT	":\n"\
"\t\tarc at $0, $1\n"\
"\t\tsize: $2 by $3\n"\
"\t\tfrom angle $4 to angle $5\n"

#define RECTANGLE_DFORMAT	":\n"\
"\t\tupper left corner: $0, $1\n"\
"\t\tsize: $2 by $3\n"

#define RGB_COLOR_MAP_DFORMAT	":\n"\
"\t\tcolormap id #: $0\n"\
"\t\tred-max: $1\n"\
"\t\tred-mult: $2\n"\
"\t\tgreen-max: $3\n"\
"\t\tgreen-mult: $4\n"\
"\t\tblue-max: $5\n"\
"\t\tblue-mult: $6\n"\
"\t\tbase-pixel: $7\n"\
"\t\tvisual id #: $8\n"\
"\t\tkill id #: $9\n"

#define WM_HINTS_DFORMAT	":\n"\
"?m0(\t\tClient accepts input or input focus: $1\n)"\
"?m1(\t\tInitial state is "\
"?$2=0(Don't Care State)"\
"?$2=1(Normal State)"\
"?$2=2(Zoomed State)"\
"?$2=3(Iconic State)"\
"?$2=4(Inactive State)"\
".\n)"\
"?m2(\t\tbitmap id # to use for icon: $3\n)"\
"?m5(\t\tbitmap id # of mask for icon: $7\n)"\
"?m3(\t\twindow id # to use for icon: $4\n)"\
"?m4(\t\tstarting position for icon: $5, $6\n)"\
"?m6(\t\twindow id # of group leader: $8\n)"\
"?m8(\t\tThe visible hint bit is set\n)"

#define WM_ICON_SIZE_DFORMAT	":\n"\
"\t\tminimum icon size: $0 by $1\n"\
"\t\tmaximum icon size: $2 by $3\n"\
"\t\tincremental size change: $4 by $5\n"

#define WM_SIZE_HINTS_DFORMAT ":\n"\
"?m0(\t\tuser specified location: $1, $2\n)"\
"?m2(\t\tprogram specified location: $1, $2\n)"\
"?m1(\t\tuser specified size: $3 by $4\n)"\
"?m3(\t\tprogram specified size: $3 by $4\n)"\
"?m4(\t\tprogram specified minimum size: $5 by $6\n)"\
"?m5(\t\tprogram specified maximum size: $7 by $8\n)"\
"?m6(\t\tprogram specified resize increment: $9 by $10\n)"\
"?m7(\t\tprogram specified minimum aspect ratio: $11/$12\n"\
"\t\tprogram specified maximum aspect ratio: $13/$14\n)"\
"?m8(\t\tprogram specified base size: $15 by $16\n)"\
"?m9(\t\twindow gravity: "\
"?$17=0(Forget)"\
"?$17=1(NorthWest)"\
"?$17=2(North)"\
"?$17=3(NorthEast)"\
"?$17=4(West)"\
"?$17=5(Center)"\
"?$17=6(East)"\
"?$17=7(SouthWest)"\
"?$17=8(South)"\
"?$17=9(SouthEast)"\
"?$17=10(Static)"\
"\n)"

#define WM_STATE_DFORMAT	 ":\n"\
"\t\twindow state: ?$0=0(Withdrawn)?$0=1(Normal)?$0=3(Iconic)\n"\
"\t\ticon window: $1\n"

static propertyRec windowPropTable[] = {
    {"ARC",		XA_ARC,		"16iiccii",   ARC_DFORMAT },
    {"ATOM",		XA_ATOM,	 "32a",	      0 },
    {"BITMAP",		XA_BITMAP,	 "32x",	      ": bitmap id # $0\n" },
    {"CARDINAL",	XA_CARDINAL,	 "0c",	      0 },
    {"COLORMAP",	XA_COLORMAP,	 "32x",	      ": colormap id # $0\n" },
    {"CURSOR",		XA_CURSOR,	 "32x",	      ": cursor id # $0\n" },
    {"DRAWABLE",	XA_DRAWABLE,	 "32x",	      ": drawable id # $0\n" },
    {"FONT",		XA_FONT,	 "32x",	      ": font id # $0\n" },
    {"INTEGER",		XA_INTEGER,	 "0i",	      0 },
    {"PIXMAP",		XA_PIXMAP,	 "32x",	      ": pixmap id # $0\n" },
    {"POINT",		XA_POINT,	 "16ii",      " = $0, $1\n" },
    {"RECTANGLE",	XA_RECTANGLE,	 "16iicc",    RECTANGLE_DFORMAT },
    {"RGB_COLOR_MAP",	XA_RGB_COLOR_MAP,"32xcccccccxx",RGB_COLOR_MAP_DFORMAT},
    {"STRING",		XA_STRING,	 "8s",	      0 },
    {"WINDOW",		XA_WINDOW,	 "32x",	      ": window id # $0+\n" },
    {"VISUALID",	XA_VISUALID,	 "32x",	      ": visual id # $0\n" },
    {"WM_COLORMAP_WINDOWS",	0,	 "32x",       ": window id # $0+\n"},
    {"WM_COMMAND",	XA_WM_COMMAND,	 "8s",	      " = { $0+ }\n" },
    {"WM_HINTS",	XA_WM_HINTS,	 "32mbcxxiixx",	WM_HINTS_DFORMAT },
    {"WM_ICON_NAME",	XA_WM_ICON_NAME, "8t",	      0 },
    {"WM_ICON_SIZE",	XA_WM_ICON_SIZE, "32cccccc",  WM_ICON_SIZE_DFORMAT},
    {"WM_NAME",		XA_WM_NAME,	 "8t",	      0 },
    {"WM_PROTOCOLS",		0,	 "32a",	      ": protocols  $0+\n"},
    {"WM_SIZE_HINTS",	XA_WM_SIZE_HINTS,"32mii",     WM_SIZE_HINTS_DFORMAT },
    {"WM_STATE",		0,	 "32cx",      WM_STATE_DFORMAT}
};
#undef ARC_DFORMAT
#undef RECTANGLE_DFORMAT
#undef RGB_COLOR_MAP_DFORMAT
#undef WM_ICON_SIZE_DFORMAT
#undef WM_HINTS_DFORMAT
#undef WM_SIZE_HINTS_DFORMAT
#undef WM_STATE_DFORMAT

/* 
 * Font-specific mapping of property names to types:
 */
static propertyRec fontPropTable[] = {

    /* XLFD name properties */

    { "FOUNDRY",		0, 	 		"32a",	0 },
    { "FAMILY_NAME",		XA_FAMILY_NAME,		"32a",	0 },
    { "WEIGHT_NAME",		0,			"32a",	0 },
    { "SLANT",			0,			"32a",	0 },
    { "SETWIDTH_NAME",		0,			"32a",	0 },
    { "ADD_STYLE_NAME",		0,			"32a",	0 },
    { "PIXEL_SIZE",		0,			"32c",	0 },
    { "POINT_SIZE",		XA_POINT_SIZE,		"32c",	0 },
    { "RESOLUTION_X",		0,			"32c",	0 },
    { "RESOLUTION_Y",		0,			"32c",	0 },
    { "SPACING",		0,			"32a",	0 },
    { "AVERAGE_WIDTH",		0,			"32c",	0 },
    { "CHARSET_REGISTRY",	0,			"32a",	0 },
    { "CHARSET_ENCODING",	0,			"32a",	0 },

    /* other font properties referenced in the XLFD */

    { "QUAD_WIDTH",		XA_QUAD_WIDTH,		"32i",	0 },
    { "RESOLUTION",		XA_RESOLUTION,		"32c",	0 },
    { "MIN_SPACE",		XA_MIN_SPACE,		"32c",	0 },
    { "NORM_SPACE",		XA_NORM_SPACE,		"32c",	0 },
    { "MAX_SPACE",		XA_MAX_SPACE,		"32c",	0 },
    { "END_SPACE",		XA_END_SPACE,		"32c",	0 },
    { "SUPERSCRIPT_X",		XA_SUPERSCRIPT_X,	"32i",	0 },
    { "SUPERSCRIPT_Y",		XA_SUPERSCRIPT_Y,	"32i",	0 },
    { "SUBSCRIPT_X",		XA_SUBSCRIPT_X,		"32i",	0 },
    { "SUBSCRIPT_Y",		XA_SUBSCRIPT_Y,		"32i",	0 },
    { "UNDERLINE_POSITION",	XA_UNDERLINE_POSITION,	"32i",	0 },
    { "UNDERLINE_THICKNESS",	XA_UNDERLINE_THICKNESS,	"32i",	0 },
    { "STRIKEOUT_ASCENT",	XA_STRIKEOUT_ASCENT,	"32i",	0 },
    { "STRIKEOUT_DESCENT",	XA_STRIKEOUT_DESCENT,	"32i",	0 },
    { "ITALIC_ANGLE",		XA_ITALIC_ANGLE,	"32i",	0 },
    { "X_HEIGHT",		XA_X_HEIGHT,		"32i",	0 },
    { "WEIGHT",			XA_WEIGHT,		"32i",	0 },
    { "FACE_NAME",		0,			"32a",	0 },
    { "COPYRIGHT",		XA_COPYRIGHT,		"32a",	0 },
    { "AVG_CAPITAL_WIDTH",	0,			"32i",	0 },
    { "AVG_LOWERCASE_WIDTH",	0,			"32i",	0 },
    { "RELATIVE_SETWIDTH",	0,			"32c",	0 },
    { "RELATIVE_WEIGHT",	0,			"32c",	0 },
    { "CAP_HEIGHT",		XA_CAP_HEIGHT,		"32c",	0 },
    { "SUPERSCRIPT_SIZE",	0,			"32c",	0 },
    { "FIGURE_WIDTH",		0,			"32i",	0 },
    { "SUBSCRIPT_SIZE",		0,			"32c",	0 },
    { "SMALL_CAP_SIZE",		0,			"32i",	0 },
    { "NOTICE",			XA_NOTICE,		"32a",	0 },
    { "DESTINATION",		0,			"32c",	0 },

    /* other font properties */

    { "FONT",			XA_FONT,		"32a",	0 },
    { "FONT_NAME",		XA_FONT_NAME,		"32a",	0 },
};    

static int XpropMode;
#define XpropWindowProperties 0
#define XpropFontProperties   1

static void
Setup_Mapping (void)
{
    int n;
    propertyRec *p;
    
    if (XpropMode == XpropWindowProperties) {
	n = sizeof(windowPropTable) / sizeof(propertyRec);
	p = windowPropTable;
    } else {
	n = sizeof (fontPropTable) / sizeof (propertyRec);
	p = fontPropTable;
    }
    for ( ; --n >= 0; p++) {
	if (! p->atom) {
	    p->atom = XInternAtom(dpy, p->name, True);
	    if (p->atom == None)
		continue;
	}
	Add_Mapping(p->atom, p->format, p->dformat);
    }	
}

static const char *
GetAtomName (Atom atom)
{
    int n;
    propertyRec *p;

    if (XpropMode == XpropWindowProperties) {
	n = sizeof(windowPropTable) / sizeof(propertyRec);
	p = windowPropTable;
    } else {
	n = sizeof (fontPropTable) / sizeof (propertyRec);
	p = fontPropTable;
    }
    for ( ; --n >= 0; p++)
	if (p->atom == atom)
	    return p->name;

    return NULL;
}

/*
 * Read_Mapping: routine to read in additional mappings from a stream
 *               already open for reading.
 */

static void
Read_Mappings (FILE *stream)
{
    char format_buffer[100];
    char name[1000], *dformat, *format;
    int count, c;
    Atom atom;

    while ((count = fscanf(stream," %990s %90s ",name,format_buffer)) != EOF) {
	if (count != 2)
	    Fatal_Error("Bad format file format.");

	atom = Parse_Atom(name, False);
	format = Copy_String(format_buffer);

	Read_White_Space(stream);
	dformat = D_DFORMAT;
	c = getc(stream);
	ungetc(c, stream);
	if (c == (int) '\'')
	    dformat = Read_Quoted(stream);

	Add_Mapping(atom, format, dformat);
    }
}

/*
 *
 * Formatting Routines: a group of routines to translate from various
 *                      values to a static read-only string useful for output.
 *
 * Routines: Format_Hex, Format_Unsigned, Format_Signed, Format_Atom,
 *           Format_Mask_Word, Format_Bool, Format_String, Format_Len_String.
 *
 * All of the above routines take a long except for Format_String and
 * Format_Len_String.
 *
 */
static char _formatting_buffer[MAXSTR+100];
static char _formatting_buffer2[21];

static const char *
Format_Hex (long wrd)
{
    sprintf(_formatting_buffer2, "0x%lx", wrd);
    return _formatting_buffer2;
}

static const char *
Format_Unsigned (long wrd)
{
    sprintf(_formatting_buffer2, "%lu", wrd);
    return _formatting_buffer2;
}

static const char *
Format_Signed (long wrd)
{
    sprintf(_formatting_buffer2, "%ld", wrd);
    return _formatting_buffer2;
}

/*ARGSUSED*/
static int
ignore_errors (Display *dpy, XErrorEvent *ev)
{
    return 0;
}

static const char *
Format_Atom (Atom atom)
{
    const char *found;
    char *name;
    XErrorHandler handler;

    if ((found = GetAtomName(atom)) != NULL)
	return found;

    handler = XSetErrorHandler (ignore_errors);
    name = XGetAtomName(dpy, atom);
    XSetErrorHandler(handler);
    if (! name)
	sprintf(_formatting_buffer, "undefined atom # 0x%lx", atom);
    else {
	int namelen = strlen(name);
	if (namelen > MAXSTR) namelen = MAXSTR;
	memcpy(_formatting_buffer, name, namelen);
	_formatting_buffer[namelen] = '\0';
	XFree(name);
    }
    return _formatting_buffer;
}

static const char *
Format_Mask_Word (long wrd)
{
    long bit_mask, bit;
    int seen = 0;

    strcpy(_formatting_buffer, "{MASK: ");
    for (bit=0, bit_mask=1; bit <= sizeof(long)*8; bit++, bit_mask<<=1) {
	if (bit_mask & wrd) {
	    if (seen) {
		strcat(_formatting_buffer, ", ");
	    }
	    seen = 1;
	    strcat(_formatting_buffer, Format_Unsigned(bit));
	}
    }
    strcat(_formatting_buffer, "}");

    return _formatting_buffer;
}

static const char *
Format_Bool (long value)
{
    if (!value)
	return "False";

    return "True";
}

static char *_buf_ptr;
static int _buf_len;

static void
_put_char (char c)
{
    if (--_buf_len < 0) {
	_buf_ptr[0] = '\0';
	return;
    }
    _buf_ptr++[0] = c;
}

static void
_format_char (char c)
{
    switch (c) {
      case '\\':
      case '\"':
	_put_char('\\');
	_put_char(c);
	break;
      case '\n':
	_put_char('\\');
	_put_char('n');
	break;
      case '\t':
	_put_char('\\');
	_put_char('t');
	break;
      default:
	if (!c_isprint(c)) {
	    _put_char('\\');
	    sprintf(_buf_ptr, "%03o", (unsigned char) c);
	    _buf_ptr += 3;
	    _buf_len -= 3;
	} else
	  _put_char(c);
    }
}

static const char *
Format_String (const char *string)
{
    char c;

    _buf_ptr = _formatting_buffer;
    _buf_len = MAXSTR;
    _put_char('\"');

    while ((c = string++[0]))
	_format_char(c);

    *_buf_ptr++ = '"';
    *_buf_ptr++ = '\0';
    return _formatting_buffer;
}

static const char *
Format_Len_String (const char *string, int len)
{
    char *data;
    const char *result;

    data = (char *) Malloc(len+1);

    memcpy(data, string, len);
    data[len] = '\0';

    result = Format_String(data);
    free(data);

    return result;
}  

static const char *
Format_Len_Text (const char *string, int len, Atom encoding)
{
    XTextProperty textprop;
    char **list;
    int count;

    /* Try to convert to local encoding. */
    textprop.encoding = encoding;
    textprop.format = 8;
    textprop.value = (unsigned char *) string;
    textprop.nitems = len;
    if (XmbTextPropertyToTextList(dpy, &textprop, &list, &count) == Success) {
	_buf_ptr = _formatting_buffer;
	_buf_len = MAXSTR;
	*_buf_ptr++ = '"';
	while (count > 0) {
	    string = *list++;
	    len = strlen(string);
	    while (len > 0) {
		wchar_t wc;
		int n = mbtowc(&wc, string, len);
		if (n > 0 && iswprint(wc)) {
		    if (_buf_len >= n) {
			memcpy(_buf_ptr, string, n);
			_buf_ptr += n;
			_buf_len -= n;
		    }
		    string += n;
		    len -= n;
		} else {
		    _put_char('\\');
		    sprintf(_buf_ptr, "%03o", (unsigned char) *string);
		    _buf_ptr += 3;
		    _buf_len -= 3;
		    string++;
		    len--;
		}
	    }
	    count--;
	    if (count > 0) {
		sprintf(_buf_ptr, "\\000");
	        _buf_ptr += 4;
		_buf_len -= 4;
	    }
	}
	*_buf_ptr++ = '"';
	*_buf_ptr++ = '\0';
	return _formatting_buffer;
    } else
	return Format_Len_String(string, len);
}

/*
 *
 * The Format Manager: a group of routines to manage "formats"
 *
 */

static int
Is_A_Format (const char *string)
{
    return isdigit((unsigned char) string[0]);
}

static int
Get_Format_Size (const char *format)
{
    long size;

    Scan_Long(format, &size);

    /* Check for legal sizes */
    if (size != 0 && size != 8 && size != 16 && size != 32)
	Fatal_Error("bad format: %s", format);

    return (int) size;
}

static char
Get_Format_Char (const char *format, int i)
{
    long size;

    /* Remove # at front of format */
    format = Scan_Long(format, &size);
    if (!*format)
	Fatal_Error("bad format: %s", format);

    /* Last character repeats forever... */
    if (i >= (int)strlen(format))
	i = strlen(format)-1;

    return format[i];
}

static const char *
Format_Thunk (thunk t, char format_char)
{
    long value;
    value = t.value;

    switch (format_char) {
      case 's':
	return Format_Len_String(t.extra_value, (int)t.value);
      case 't':
	return Format_Len_Text(t.extra_value, (int)t.value, t.extra_encoding);
      case 'x':
	return Format_Hex(value);
      case 'c':
	return Format_Unsigned(value);
      case 'i':
	return Format_Signed(value);
      case 'b':
	return Format_Bool(value);
      case 'm':
	return Format_Mask_Word(value);
      case 'a':
	return Format_Atom(value);
      default:
	Fatal_Error("bad format character: %c", format_char);
    }
}

static const char *
Format_Thunk_I (thunk *thunks, const char *format, int i)
{
    if (i >= thunks->thunk_count)
	return "<field not available>";

    return Format_Thunk(thunks[i], Get_Format_Char(format, i));
}

static long
Mask_Word (thunk *thunks, const char *format)
{
    int j;

    for (j = 0; j  < (int)strlen(format); j++)
	if (Get_Format_Char(format, j) == 'm')
	    return thunks[j].value;
    return 0;
}

/*
 *
 * The Display Format Manager:
 *
 */

static int
Is_A_DFormat (const char *string)
{
    return string[0] && string[0] != '-'
	   && !(isalpha((unsigned char) string[0]) || string[0] == '_');
}

static const char *
Handle_Backslash (const char *dformat)
{
    char c;
    unsigned long i;

    if (!(c = *(dformat++)))
	return dformat;

    switch (c) {
      case 'n':
	putchar('\n');
	break;
      case 't':
	putchar('\t');
	break;
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
	dformat = Scan_Octal(dformat, &i);
	putchar((int) i);
	break;
      default:
	putchar(c);
	break;
    }
    return dformat;
}

static const char *
Handle_Dollar_sign (const char *dformat, thunk *thunks, const char *format)
{
    long i;

    dformat = Scan_Long(dformat, &i);

    if (dformat[0] == '+') {
	int seen = 0;
	dformat++;
	for (; i < thunks->thunk_count; i++) {
	    if (seen)
		printf(", ");
	    seen = 1;
	    printf("%s", Format_Thunk_I(thunks, format, (int) i));
	}
    } else
	printf("%s", Format_Thunk_I(thunks, format, (int) i));

    return dformat;
}

static int
Mask_Bit_I (thunk *thunks, const char *format, int i)
{
    long value;

    value = Mask_Word(thunks, format);

    value = value & (1L<<i);
    if (value)
	value = 1;
    return value;
}

static const char *
Scan_Term (const char *string, thunk *thunks, const char *format, long *value)
{
    long i;

    *value = 0;

    if (isdigit((unsigned char) *string))
	string = Scan_Long(string, value);
    else if (*string == '$') {
	string = Scan_Long(++string, &i);
	if (i >= thunks->thunk_count)
	    i = thunks->thunk_count;
	*value = thunks[i].value;
    } else if (*string == 'm') {
	string = Scan_Long(++string, &i);
	*value = Mask_Bit_I(thunks, format, (int) i);
    } else
	Fatal_Error("Bad term: %s.", string);

    return string;
}

static const char *
Scan_Exp (const char *string, thunk *thunks, const char *format, long *value)
{
    long temp;

    if (string[0] == '(') {
	string = Scan_Exp(++string, thunks, format, value);
	if (string[0]!=')')
	    Fatal_Error("Missing ')'");
	return ++string;
    }
    if (string[0] == '!') {
	string = Scan_Exp(++string, thunks, format, value);
	*value = !*value;
	return string;
    }

    string = Scan_Term(string, thunks, format, value);

    if (string[0] == '=') {
	string = Scan_Exp(++string, thunks, format, &temp);
	*value = *value == temp;
    }

    return string;
}

static const char *
Handle_Question_Mark (const char *dformat, thunk *thunks, const char *format)
{
    long true;

    dformat = Scan_Exp(dformat, thunks, format, &true);

    if (*dformat != '(')
	Fatal_Error("Bad conditional: '(' expected: %s.", dformat);
    ++dformat;

    if (!true)
	dformat = Skip_Past_Right_Paren(dformat);

    return dformat;
}

static void
Display_Property (thunk *thunks, const char *dformat, const char *format)
{
    char c;

    while ((c = *(dformat++)))
	switch (c) {
	  case ')':
	    continue;
	  case '\\':
	    dformat = Handle_Backslash(dformat);
	    continue;
	  case '$':
	    dformat = Handle_Dollar_sign(dformat, thunks, format);
	    continue;
	  case '?':
	    dformat = Handle_Question_Mark(dformat, thunks, format);
	    continue;
	  default:
	    putchar(c);
	    continue;
	}
}

/*
 *
 * Routines to convert property data to thunks
 *
 */

static long
Extract_Value (const char **pointer, int *length, int size, int signedp)
{
    long value;

    switch (size) {
      case 8:
	if (signedp)
	    value = * (const signed char *) *pointer;
	else
	    value = * (const unsigned char *) *pointer;
	*pointer += 1;
	*length -= 1;
	break;
      case 16:
	if (signedp)
	    value = * (const short *) *pointer;
	else
	    value = * (const unsigned short *) *pointer;
	*pointer += sizeof(short);
	*length -= sizeof(short);
	break;
      case 32:
	if (signedp)
	    value = * (const long *) *pointer;
	else
	    value = * (const unsigned long *) *pointer & 0xffffffff;
	*pointer += sizeof(long);
	*length -= sizeof(long);
	break;
      default:
	abort();
    }
    return value;
}

static long
Extract_Len_String (const char **pointer, int *length, int size, const char **string)
{
    int len;

    if (size != 8)
	Fatal_Error("can't use format character 's' with any size except 8.");
    len = 0; *string = *pointer;
    while ((len++, --*length, *((*pointer)++)) && *length>0);

    return len;
}

static thunk *
Break_Down_Property (const char *pointer, int length, Atom type, const char *format, int size)
{
    thunk *thunks;
    thunk t;
    int i;
    char format_char;

    thunks = Create_Thunk_List();
    i = 0;

    while (length >= size/8) {
	format_char = Get_Format_Char(format, i);
	if (format_char == 's')
	    t.value = Extract_Len_String(&pointer,&length,size,&t.extra_value);
	else if (format_char == 't') {
	    t.extra_encoding = type;
	    t.value = Extract_Len_String(&pointer,&length,size,&t.extra_value);
	} else
	    t.value = Extract_Value(&pointer,&length,size,format_char=='i');
	thunks = Add_Thunk(thunks, t);
	i++;
    }

    return thunks;
}

/*
 * Variables set by main()
 */

static Window target_win = 0;
static int notype = 0;
static int max_len = MAXSTR;
static XFontStruct *font;
static unsigned long _font_prop;

/*
 *
 * Other Stuff (temp.):
 *
 */

static const char *
Get_Font_Property_Data_And_Type (Atom atom,
                                 long *length, Atom *type, int *size)
{
    int i;
	
    *type = None;
	
    for (i = 0; i < font->n_properties; i++)
	if (atom == font->properties[i].name) {
	    _font_prop = font->properties[i].card32;
	    *length = sizeof(long);
	    *size = 32;
	    return (const char *) &_font_prop;
	}
    *size = 0;
    return NULL;
}

static const char *
Get_Window_Property_Data_And_Type (Atom atom,
                                   long *length, Atom *type, int *size)
{
    Atom actual_type;
    int actual_format;
    unsigned long nitems;
    unsigned long nbytes;
    unsigned long bytes_after;
    unsigned char *prop;
    int status;
	
    status = XGetWindowProperty(dpy, target_win, atom, 0, (max_len+3)/4,
				False, AnyPropertyType, &actual_type,
				&actual_format, &nitems, &bytes_after,
				&prop);
    if (status == BadWindow)
	Fatal_Error("window id # 0x%lx does not exists!", target_win);
    if (status != Success)
	Fatal_Error("XGetWindowProperty failed!");

    if (actual_format == 32)
	nbytes = sizeof(long);
    else if (actual_format == 16)
	nbytes = sizeof(short);
    else if (actual_format == 8)
	nbytes = 1;
    else if (actual_format == 0)
        nbytes = 0;
    else
	abort();
    *length = min(nitems * nbytes, max_len);
    *type = actual_type;
    *size = actual_format;
    return (const char *)prop;
}

static const char *
Get_Property_Data_And_Type (Atom atom, long *length, Atom *type, int *size)
{
    if (target_win == -1)
	return Get_Font_Property_Data_And_Type(atom, length, type, size);
    else
	return Get_Window_Property_Data_And_Type(atom, length, type, size);
}

static void
Show_Prop (const char *format, const char *dformat, const char *prop)
{
    const char *data;
    long length;
    Atom atom, type;
    thunk *thunks;
    int size, fsize;

    printf("%s", prop);
    atom = Parse_Atom(prop, True);
    if (atom == None) {
	printf(":  no such atom on any window.\n");
	return;
    }

    data = Get_Property_Data_And_Type(atom, &length, &type, &size);
    if (!size) {
	puts(":  not found.");
	return;
    }

    if (!notype && type != None)
	printf("(%s)", Format_Atom(type));

    Lookup_Formats(atom, &format, &dformat);
    if (type != None)
	Lookup_Formats(type, &format, &dformat);
    Apply_Default_Formats(&format, &dformat);

    fsize = Get_Format_Size(format);
    if (fsize != size && fsize != 0) {
	printf(": Type mismatch: assumed size %d bits, actual size %d bits.\n",
	       fsize, size);
	return;
    }

    thunks = Break_Down_Property(data, (int)length, type, format, size);

    Display_Property(thunks, dformat, format);
}

static void
Show_All_Props (void)
{
    Atom *atoms, atom;
    const char *name;
    int count, i;

    if (target_win != -1) {
	atoms = XListProperties(dpy, target_win, &count);
	for (i = 0; i < count; i++) {
	    name = Format_Atom(atoms[i]);
	    Show_Prop(NULL, NULL, name);
	}
    } else
	for (i = 0; i < font->n_properties; i++) {
	    atom = font->properties[i].name;
	    name = Format_Atom(atom);
	    Show_Prop(NULL, NULL, name);
	}
}

static thunk *
Handle_Prop_Requests (int argc, char **argv)
{
    char *format, *dformat, *prop;
    thunk *thunks, t;

    thunks = Create_Thunk_List();

    /* if no prop referenced, by default list all properties for given window */
    if (!argc) {
	Show_All_Props();
	return NULL;
    }

    while (argc > 0) {
	format = NULL;
	dformat = NULL;

	/* Get overriding formats, if any */
	if (Is_A_Format(argv[0])) {
	    format = argv++[0]; argc--;
	    if (!argc) usage();
	}
	if (Is_A_DFormat(argv[0])) {
	    dformat = argv++[0]; argc--;
	    if (!argc) usage();
	}

	/* Get property name */
	prop = argv++[0]; argc--;

	t.propname = prop;
	t.value = Parse_Atom(prop, True);
	t.format = format;
	t.dformat = dformat;
	if (t.value)
	    thunks = Add_Thunk(thunks, t);
	Show_Prop(format, dformat, prop);
    }
    return thunks;
}

static void
Remove_Property (Display *dpy, Window w, const char *propname)
{
    Atom id = XInternAtom (dpy, propname, True);

    if (id == None) {
	fprintf (stderr, "%s:  no such property \"%s\"\n",
		 program_name, propname);
	return;
    }
    XDeleteProperty (dpy, w, id);
}

static void
Set_Property (Display *dpy, Window w, const char *propname, const char *value)
{
    Atom atom;
    const char *format;
    const char *dformat;
    int size;
    char format_char;
    Atom type = 0;
    unsigned char *data = NULL;
    int nelements = 0;

    atom = Parse_Atom(propname, False);

    format = dformat = NULL;
    Lookup_Formats(atom, &format, &dformat);
    if (format == NULL)
	Fatal_Error("unsupported conversion for %s", propname);

    size = Get_Format_Size(format);

    format_char = Get_Format_Char(format, 0);
    switch (format_char) {
      case 's':
	if (size != 8)
	    Fatal_Error("can't use format character 's' with any size except 8.");
	type = XA_STRING;
	data = (unsigned char *) value;
	nelements = strlen(value);
	break;
      case 't': {
	XTextProperty textprop;
	if (size != 8)
	    Fatal_Error("can't use format character 't' with any size except 8.");
	if (XmbTextListToTextProperty(dpy, (char **) &value, 1,
				      XStdICCTextStyle, &textprop) != Success) {
	    fprintf(stderr, "cannot convert %s argument to STRING or COMPOUND_TEXT.\n", propname);
	    return;
	}
	type = textprop.encoding;
	data = textprop.value;
	nelements = textprop.nitems;
	break;
      }
      case 'x':
      case 'c': {
	static unsigned char data8[MAXELEMENTS];
	static unsigned short data16[MAXELEMENTS];
	static unsigned long data32[MAXELEMENTS];
	unsigned long intvalue;
	char * value2 = strdup(value);
	char * tmp = strtok(value2,",");
	nelements = 1;
	intvalue = strtoul(tmp, NULL, 0);
	switch(size) {
	    case 8:
	        data8[0] = intvalue; data = (unsigned char *) data8; break;
	    case 16:    
	        data16[0] = intvalue; data = (unsigned char *) data16; break;
	    case 32:    
	        data32[0] = intvalue; data = (unsigned char *) data32; break;
	}
	tmp = strtok(NULL,",");
	while(tmp != NULL){
	    intvalue = strtoul(tmp, NULL,0);
	    switch(size) {
		case 8:
	    	    data8[nelements] = intvalue; break;
		case 16:    
	    	    data16[nelements] = intvalue; break;
		case 32:    
	    	    data32[nelements] = intvalue; break;
	    }
	    nelements++;
	    if(nelements == MAXELEMENTS){
		fprintf(stderr, "Maximum number of elements reached (%d). List truncated.\n",MAXELEMENTS);
		break;
	    }
	    tmp = strtok(NULL,",");
	}
	
	type = XA_CARDINAL;
	free(value2);
	break;
      }
      case 'i': {
	static unsigned char data8[MAXELEMENTS];
	static unsigned short data16[MAXELEMENTS];
	static unsigned long data32[MAXELEMENTS];
	unsigned long intvalue;
	char * value2 = strdup(value);
	char * tmp = strtok(value2,",");
	nelements = 1;
	intvalue = strtoul(tmp, NULL, 0);
	switch(size) {
	    case 8:
	        data8[0] = intvalue; data = (unsigned char *) data8; break;
	    case 16:    
	        data16[0] = intvalue; data = (unsigned char *) data16; break;
	    case 32:    
	        data32[0] = intvalue; data = (unsigned char *) data32; break;
	}
	tmp = strtok(NULL,",");
	while(tmp != NULL){
	    intvalue = strtoul(tmp, NULL,0);
	    switch(size) {
		case 8:
	    	    data8[nelements] = intvalue; break;
		case 16:    
	    	    data16[nelements] = intvalue; break;
		case 32:    
	    	    data32[nelements] = intvalue; break;
	    }
	    nelements++;
	    if(nelements == MAXELEMENTS){
		fprintf(stderr, "Maximum number of elements reached (%d). List truncated.\n",MAXELEMENTS);
		break;
	    }
	    tmp = strtok(NULL,",");
	}
	
	type = XA_INTEGER;
	free(value2);
	break;
      }
      case 'b': {
	unsigned long boolvalue;
	static unsigned char data8;
	static unsigned short data16;
	static unsigned long data32;
	if (!strcmp(value, "True"))
	    boolvalue = 1;
	else if (!strcmp(value, "False"))
	    boolvalue = 0;
	else {
	    fprintf(stderr, "cannot convert %s argument to Bool\n", propname);
	    return;
	}
	type = XA_INTEGER;
	switch (size) {
	  case 8:
	    data8 = boolvalue; data = (unsigned char *) &data8; break;
	  case 16:
	    data16 = boolvalue; data = (unsigned char *) &data16; break;
	  case 32: default:
	    data32 = boolvalue; data = (unsigned char *) &data32; break;
	}
	nelements = 1;
	break;
      }
      case 'a': {
	static Atom avalue;
	avalue = Parse_Atom(value, False);
	type = XA_ATOM;
	data = (unsigned char *) &avalue;
	nelements = 1;
	break;
      }
      case 'm':
	/* NYI */
      default:
	Fatal_Error("bad format character: %c", format_char);
    }

    XChangeProperty(dpy, target_win, atom, type, size, PropModeReplace,
		    data, nelements);
}

/*
 * 
 * Routines for parsing command line:
 *
 */

void
usage (void)
{
    char **cpp;
    static char *help_message[] = {
"where options include:",
"    -grammar                       print out full grammar for command line",
"    -display host:dpy              the X server to contact",
"    -id id                         resource id of window to examine",
"    -name name                     name of window to examine",
"    -font name                     name of font to examine",
"    -remove propname               remove a property",
"    -set propname value            set a property to a given value",
"    -root                          examine the root window",
"    -len n                         display at most n bytes of any property",
"    -notype                        do not display the type field",
"    -fs filename                   where to look for formats for properties",
"    -frame                         don't ignore window manager frames",
"    -f propname format [dformat]   formats to use for property of given name",
"    -spy                           examine window properties forever",
NULL};

    fflush (stdout);
    fprintf (stderr,
	     "usage:  %s [-options ...] [[format [dformat]] atom] ...\n\n", 
	     program_name);
    for (cpp = help_message; *cpp; cpp++) {
	fprintf (stderr, "%s\n", *cpp);
    }
    fprintf (stderr, "\n");
    exit (1);
}

static void
grammar (void)
{
    printf ("Grammar for xprop:\n\n");
    printf("\t%s [<disp>] [<select option>] <option>* <mapping>* <spec>*",
	   program_name);
    printf("\n\n\tdisp ::= -display host:dpy\
\n\tselect option ::= -root | -id <id> | -font <font> | -name <name>\
\n\toption ::= -len <n> | -notype | -spy | {-formats|-fs} <format file>\
\n\tmapping ::= {-f|-format} <atom> <format> [<dformat>]\
\n\t            | -remove <propname>\
\n\t            | -set <propname> <value>\
\n\tspec ::= [<format> [<dformat>]] <atom>\
\n\tformat ::= {0|8|16|32}{a|b|c|i|m|s|t|x}*\
\n\tdformat ::= <unit><unit>*             (can't start with a letter or '-')\
\n\tunit ::= ?<exp>(<unit>*) | $<n> | <display char>\
\n\texp ::= <term> | <term>=<exp> | !<exp>\
\n\tterm ::= <n> | $<n> | m<n>\
\n\tdisplay char ::= <normal char> | \\<non digit char> | \\<octal number>\
\n\tnormal char ::= <any char except a digit, $, ?, \\, or )>\
\n\n");
    exit(0);
}

static void
Parse_Format_Mapping (int *argc, char ***argv)
{
#define ARGC (*argc)
#define ARGV (*argv)
#define OPTION ARGV[0]
#define NXTOPT if (++ARGV, --ARGC==0) usage()
    char *type_name, *format, *dformat;
  
    NXTOPT; type_name = OPTION;

    NXTOPT; format = OPTION;
    if (!Is_A_Format(format))
	Fatal_Error("Bad format: %s.", format);

    dformat = NULL;
    if (ARGC>1 && Is_A_DFormat(ARGV[1])) {
	ARGV++; ARGC--; dformat = OPTION;
    }

    Add_Mapping(Parse_Atom(type_name, False), format, dformat);
}

/*
 *
 * The Main Program:
 *
 */

static int spy = 0;

int
main (int argc, char **argv)
{
    FILE *stream;
    char *name;
    thunk *props;
    thunk *remove_props = NULL;
    thunk *set_props = NULL;
    Bool frame_only = False;
    int n;
    char **nargv;

    INIT_NAME;

    /* Set locale for XmbTextProptertyToTextList and iswprint(). */
    setlocale(LC_CTYPE, "");

    /* Handle display name, opening the display */
    Setup_Display_And_Screen(&argc, argv);

    /* Handle selecting the window to display properties for */
    target_win = Select_Window_Args(&argc, argv);

    /* Set up default atom to format, dformat mapping */
    XpropMode = XpropWindowProperties;
    for (n = argc, nargv = argv; n; nargv++, n--)
	if (! strcmp(nargv[0], "-font")) {
	    XpropMode = XpropFontProperties;
	    break;
	}
    Setup_Mapping();
    if ((name = getenv("XPROPFORMATS"))) {
	if (!(stream = fopen(name, "r")))
	    Fatal_Error("unable to open file %s for reading.", name);
	Read_Mappings(stream);
	fclose(stream);
    }

    /* Handle '-' options to setup xprop, select window to work on */
    while (argv++, --argc>0 && **argv == '-') {
	if (!strcmp(argv[0], "-"))
	    continue;
	if (!strcmp(argv[0], "-grammar")) {
	    grammar ();
	    /* NOTREACHED */
	}
	if (!strcmp(argv[0], "-notype")) {
	    notype = 1;
	    continue;
	}
	if (!strcmp(argv[0], "-spy")) {
	    spy = 1;
	    continue;
	}
	if (!strcmp(argv[0], "-len")) {
	    if (++argv, --argc == 0) usage();
	    max_len = atoi(argv[0]);
	    continue;
	}
	if (!strcmp(argv[0], "-formats") || !strcmp(argv[0], "-fs")) {
	    if (++argv, --argc == 0) usage();
	    if (!(stream = fopen(argv[0], "r")))
		Fatal_Error("unable to open file %s for reading.", argv[0]);
	    Read_Mappings(stream);
	    fclose(stream);
	    continue;
	}
	if (!strcmp(argv[0], "-font")) {
	    if (++argv, --argc == 0) usage();
	    font = Open_Font(argv[0]);
	    target_win = -1;
	    continue;
	}
	if (!strcmp(argv[0], "-remove")) {
	    thunk t;
	    if (++argv, --argc == 0) usage();
	    t.propname = argv[0];
	    if (remove_props == NULL) remove_props = Create_Thunk_List();
	    remove_props = Add_Thunk(remove_props, t);
	    continue;
	}
	if (!strcmp(argv[0], "-set")) {
	    thunk t;
	    if (argc < 3) usage();
	    t.propname = argv[1];
	    t.extra_value = argv[2];
	    argv += 3; argc -= 3;
	    if (set_props == NULL) set_props = Create_Thunk_List();
	    set_props = Add_Thunk(set_props, t);
	    continue;
	}
	if (!strcmp(argv[0], "-frame")) {
	    frame_only = True;
	    continue;
	}
	if (!strcmp(argv[0], "-f") || !strcmp(argv[0], "-format")) {
	    Parse_Format_Mapping(&argc, &argv);
	    continue;
	}
	usage();
    }

    if ((remove_props != NULL || set_props != NULL) && argc > 0)
	usage();

    if (target_win == None) {
	target_win = Select_Window(dpy);
	if (target_win != None && !frame_only) {
	    Window root;
	    int dummyi;
	    unsigned int dummy;

	    if (XGetGeometry (dpy, target_win, &root, &dummyi, &dummyi,
			      &dummy, &dummy, &dummy, &dummy)
		&& target_win != root)
		target_win = XmuClientWindow (dpy, target_win);
	}
    }

    if (remove_props != NULL) {
	int count;

	if (target_win == -1)
	    Fatal_Error("-remove works only on windows, not fonts");

	count = remove_props->thunk_count;
	for (; count > 0; remove_props++, count--)
	    Remove_Property (dpy, target_win, remove_props->propname);
    }

    if (set_props != NULL) {
	int count;

	if (target_win == -1)
	    Fatal_Error("-set works only on windows, not fonts");

	count = set_props->thunk_count;
	for (; count > 0; set_props++, count--)
	    Set_Property (dpy, target_win, set_props->propname,
			  set_props->extra_value);
    }

    if (remove_props != NULL || set_props != NULL) {
	XCloseDisplay (dpy);
	exit (0);
    }

    props = Handle_Prop_Requests(argc, argv);

    if (spy && target_win != -1) {
	XEvent event;
	const char *format, *dformat;
	
	XSelectInput(dpy, target_win, PropertyChangeMask);
	for (;;) {
	    XNextEvent(dpy, &event);
	    format = dformat = NULL;
	    if (props) {
		int i;
		for (i = 0; i < props->thunk_count; i++)
		    if (props[i].value == event.xproperty.atom)
			break;
		if (i >= props->thunk_count)
		    continue;
		format = props[i].format;
		dformat = props[i].dformat;
	    }
	    Show_Prop(format, dformat, Format_Atom(event.xproperty.atom));
	}
    }
    exit (0);
}