* generic/tkImgPNG.c (WriteIDAT): [Bug 2984787]: Use the correct

	flushing semantics when handling the last data from the image. Without
	this, many PNG readers (notably including Firefox) refuse to show the
	image and instead complain about errors.
	(ReadIDAT): Added sanity checks to ensure that when we've got bad data
	of the sorts of forms we were previously generating, we detect it and
	error out rather than silently failing.
	(WriteExtraChunks): New function to write in some basic metadata.

1 files changed, 14 insertions, 6 deletions

diff --git a/tests/imgPNG.test b/tests/imgPNG.test
index 7fb2622..1cfaad0 100644
--- a/tests/imgPNG.test
+++ b/tests/imgPNG.test
@@ -8,7 +8,7 @@
 # Copyright (c) 2008 Donal K. Fellows
 # All rights reserved.
 #
-# RCS: @(#) $Id: imgPNG.test,v 1.2 2009/01/13 01:46:06 patthoyts Exp $
+# RCS: @(#) $Id: imgPNG.test,v 1.3 2010/04/12 08:40:17 dkf Exp $
 
 package require tcltest 2.2
 namespace import ::tcltest::*
@@ -19,16 +19,20 @@ imageInit
 namespace eval png {
     variable encoded
     # Key names are from the names of the source images, which come from
-    # http://www.schaik.com/pngsuite/pngsuite.html
+    #    http://www.schaik.com/pngsuite/pngsuite.html
+    # The exception is "BadX", which is used to test handling badly compressed
+    # images.
     array set encoded {
 	basn0g08 "iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAAAAABWESUoAAAABGdBTUEAAYagMeiWXwAAAEFJREFUeJxjZGAkABQIyLMMBQWMDwgp+PcfP2B5MBwUMMoRkGdkonlcDAYFjI/wyv7/z/iH5nExGBQwyuCVZWQEAFDl/nE14thZAAAAAElFTkSuQmCC"
 	basn2c08 "iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAIAAAD8GO2jAAAABGdBTUEAAYagMeiWXwAAAEhJREFUeJzt1cEJADAMAkCF7JH9t3ITO0Qr9KH4zuErtA0EO4AKFPgcoO3kfUx4QIECD0qHH8KEBxQo8KB0OCOpQIG7cHejwAGCsfleD0DPSwAAAABJRU5ErkJggg=="
 	basn3p08 "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"
 	basn6a08 "iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAYAAABzenr0AAAABGdBTUEAAYagMeiWXwAAAG9JREFUeJzt1jEKgDAMRuEnZGhPofc/VQSPIcTdxUV4HVLoUCj8H00o2YoBMF57fpz/ujODHXUFRwPKBqj5DVigB041HiJ9gFyCVOMbsEIPXNwuAHkgiJL/4qABNqB7QAeUPBAE2QAZUDZAfwEb8ABSIBqcFg+4TAAAAABJRU5ErkJggg=="
+
+	BadX "iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAABHNCSVQICAgIfAhkiAAAABN0RVh0U29mdHdhcmUAVGsgOC42YjEuMcrtT1oAAAAcSURBVHicYmBgYPjPgAr+ozP+o0uj68BUiWEmAAAA//8SozfjAAAAAElFTkSuQmCC"
     }
 
 # $encoded(basn0g08), $encoded(basn2c08), $encoded(basn3p08), $encoded(basn6a08)
-test png-1.1 {reading basic images; grayscale} -setup {
+test imgPNG-1.1 {reading basic images; grayscale} -setup {
     catch {rename foo ""}
 } -body {
     image create photo foo -data $encoded(basn0g08)
@@ -36,7 +40,7 @@ test png-1.1 {reading basic images; grayscale} -setup {
 } -cleanup {
     rename foo ""
 } -result {32 32}
-test png-1.2 {reading basic images; color} -setup {
+test imgPNG-1.2 {reading basic images; color} -setup {
     catch {rename foo ""}
 } -body {
     image create photo foo -data $encoded(basn2c08)
@@ -44,7 +48,7 @@ test png-1.2 {reading basic images; color} -setup {
 } -cleanup {
     rename foo ""
 } -result {32 32}
-test png-1.3 {reading basic images; color with palette} -setup {
+test imgPNG-1.3 {reading basic images; color with palette} -setup {
     catch {rename foo ""}
 } -body {
     image create photo foo -data $encoded(basn3p08)
@@ -52,7 +56,7 @@ test png-1.3 {reading basic images; color with palette} -setup {
 } -cleanup {
     rename foo ""
 } -result {32 32}
-test png-1.4 {reading basic images; alpha} -setup {
+test imgPNG-1.4 {reading basic images; alpha} -setup {
     catch {rename foo ""}
 } -body {
     image create photo foo -data $encoded(basn6a08)
@@ -60,6 +64,10 @@ test png-1.4 {reading basic images; alpha} -setup {
 } -cleanup {
     rename foo ""
 } -result {32 32}
+
+test imgPNG-2.1 {reading a bad image} -body {
+    image create photo -data $encoded(BadX)
+} -returnCodes error -result {unfinalized data stream in PNG data}
 
 }
 namespace delete png