# HG changeset patch
# User Matti Hamalainen <ccr@tnsp.org>
# Date 1349893389 -10800
# Node ID 31e62b1f1b6ec8e3b88b761a53ea8170eb41aa53
# Parent  3b5493fac9289bee5eafd007fc3d8a62e5a77441
Add boundary checks for the scope drawing.

diff -r 3b5493fac928 -r 31e62b1f1b6e ppl.c
--- a/ppl.c	Wed Oct 10 20:45:10 2012 +0300
+++ b/ppl.c	Wed Oct 10 21:23:09 2012 +0300
@@ -262,6 +262,7 @@
 
     int xc, ym = y0 + (y1 - y0) / 2, vol = FP_GETH(chn->chVolume);
     int pitch = screen->pitch / sizeof(Uint32);
+    int len = chn->chSize;
     DMFixedPoint offs = chn->chPos;
     Uint32 coln = dmCol(0.0, 0.8, 0.0), colx = dmCol(1.0, 0, 0);
     Uint32 *pix = screen->pixels;
@@ -276,14 +277,27 @@
     if (chn->chData == NULL || !chn->chPlaying)
         return;
 
-    for (xc = x0 + 1; xc < x1 - 1; xc++)
+    if (chn->chDirection)
     {
-        Sint16 val = ym + (data[FP_GETH(offs)] * yh * vol) / (65535 * 255);
-        pix[xc + val * pitch] = coln;
-        if (chn->chDirection)
+        for (xc = x0 + 1; xc < x1 - 1; xc++)
+        {
+            if (FP_GETH(offs) >= len)
+                break;
+            Sint16 val = ym + (data[FP_GETH(offs)] * yh * vol) / (65535 * 255);
+            pix[xc + val * pitch] = coln;
             FP_ADD(offs, chn->chDeltaO);
-        else
+        }
+    }
+    else
+    {
+        for (xc = x0 + 1; xc < x1 - 1; xc++)
+        {
+            if (FP_GETH(offs) < 0)
+                break;
+            Sint16 val = ym + (data[FP_GETH(offs)] * yh * vol) / (65535 * 255);
+            pix[xc + val * pitch] = coln;
             FP_SUB(offs, chn->chDeltaO);
+        }
     }
 }