From 44bc3084ec36302edcb0bb01854245158dbbfe8a Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Tue, 6 Dec 2005 19:49:12 +0000
Subject: [PATCH] avoid overlong strings in Xft measures and in editors

svn: r1540
---
 src/mred/wxme/wx_media.cxx              | 24 ++++++++++++++----------
 src/wxxt/src/DeviceContexts/WindowDC.cc | 25 +++++++++++++++++++++----
 2 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/src/mred/wxme/wx_media.cxx b/src/mred/wxme/wx_media.cxx
index 08f1e6835a..9e2f115ff0 100644
--- a/src/mred/wxme/wx_media.cxx
+++ b/src/mred/wxme/wx_media.cxx
@@ -1577,7 +1577,7 @@ void wxMediaEdit::_Insert(wxSnip *isnip, long strlen, wxchar *str, wxList *snips
 	break;
     }
   } else {
-    int sp;
+    int sp, cnt;
 
     addlen = strlen;
     
@@ -1677,6 +1677,7 @@ void wxMediaEdit::_Insert(wxSnip *isnip, long strlen, wxchar *str, wxList *snips
     snipStartPos = start;
     str = snip->buffer;
     sp = s + snip->dtext;
+    cnt = 0;
     for (i = 0; i < addlen; i++) {
       if (str[sp] == '\r')
 	str[sp] = '\n';
@@ -1766,16 +1767,19 @@ void wxMediaEdit::_Insert(wxSnip *isnip, long strlen, wxchar *str, wxList *snips
 	snipStartPos = i + start + 1;
 	str = snip->buffer;
 	sp = snip->dtext;
-      } else
+	cnt = 0;
+      } else if (cnt > MAX_COUNT_FOR_SNIP) {
+	/* Divide up snip because it's too large: */
+	MakeSnipset(i + start, i + start);
+	snip = (wxTextSnip *)FindSnip(i + start, +1);
+	snipStartPos = i + start;
+	str = snip->buffer;
+	sp = snip->dtext + 1;
+	cnt = 1;
+      } else {
 	sp++;
-    }
-
-    /* Divide up snip if it's too large: */
-    while (snip->count > MAX_COUNT_FOR_SNIP) {
-      long next = snipStartPos + MAX_COUNT_FOR_SNIP - 10;
-      MakeSnipset(snipStartPos, next);
-      snip = (wxTextSnip *)FindSnip(next, +1);
-      snipStartPos = next;
+	cnt++;
+      }
     }
 
     firstLine = lineRoot->First();
diff --git a/src/wxxt/src/DeviceContexts/WindowDC.cc b/src/wxxt/src/DeviceContexts/WindowDC.cc
index ccab51f84d..754d3093ce 100644
--- a/src/wxxt/src/DeviceContexts/WindowDC.cc
+++ b/src/wxxt/src/DeviceContexts/WindowDC.cc
@@ -2216,6 +2216,10 @@ static unsigned int *convert_to_drawable_format(const char *s, int ds, long *_ul
 #endif
 static unsigned int cvt_buf[WX_CVT_BUF_SIZE];
 
+/* Xft measurements use a `short'. Avoid string lengths that are
+   likely to overflow it. */
+#define MAX_TEXT_LENGTH_FOR_MEASURE 100
+
 void wxWindowDC::DrawText(char *orig_text, double x, double y, 
 			  Bool combine, Bool isUnicode, int dt,
 			  double angle)
@@ -2352,6 +2356,12 @@ void wxWindowDC::DrawText(char *orig_text, double x, double y,
       try_sub = 1;
 
       while(textlen) {
+	int nowlen;
+	nowlen = textlen;
+	if (nowlen > MAX_TEXT_LENGTH_FOR_MEASURE) {
+	  nowlen = MAX_TEXT_LENGTH_FOR_MEASURE;
+	}
+
 	if (angle != 0.0)
 	  no_rotate = (wxFontStruct*)current_font->GetInternalAAFont(e_scale_x, e_scale_y, 0.0);
 	else
@@ -2381,7 +2391,7 @@ void wxWindowDC::DrawText(char *orig_text, double x, double y,
 	  
 	  /* Get a longer range that won't need a substitution */
 	  if (this_time == xfontinfo) {
-	    while (partlen < textlen) {
+	    while (partlen < nowlen) {
 	      cval = text[dt + partlen];
 	      if (((this_time != xfontinfo)
 		   && XftGlyphExists(DPY, xfontinfo, cval))
@@ -2391,7 +2401,7 @@ void wxWindowDC::DrawText(char *orig_text, double x, double y,
 	    }
 	  }
 	} else {
-	  partlen = textlen;
+	  partlen = nowlen;
 	  this_time = xfontinfo;
 	  this_time_no_rotate = no_rotate;
 	}
@@ -2532,10 +2542,17 @@ void wxGetTextExtent(Display *dpy, double scale_x, double scale_y,
     w = 0;
 
     while (textlen) {
+      int nowlen;
+      nowlen = textlen;
+      if (nowlen > MAX_TEXT_LENGTH_FOR_MEASURE) {
+	nowlen = MAX_TEXT_LENGTH_FOR_MEASURE;
+      }
+
       if (try_sub) {
 	int index = 1, cval;
 	partlen = 1;
 	this_time = xfontinfo;
+	
 	while (1) {
 	  cval = s[dt];
 	  if (!XftGlyphExists(dpy, this_time, cval)) {
@@ -2550,7 +2567,7 @@ void wxGetTextExtent(Display *dpy, double scale_x, double scale_y,
 
 	/* Get a longer range that won't need a substitution */
 	if (this_time == xfontinfo) {
-	  while (partlen < textlen) {
+	  while (partlen < nowlen) {
 	    cval = s[dt + partlen];
 	    if (((this_time != xfontinfo)
 		 && XftGlyphExists(dpy, xfontinfo, cval))
@@ -2560,7 +2577,7 @@ void wxGetTextExtent(Display *dpy, double scale_x, double scale_y,
 	  }
 	}
       } else {
-	partlen = textlen;
+	partlen = nowlen;
 	this_time = xfontinfo;
       }