Bug#991067: x4d-icons FTBFS with imagemagick with the #987504 change

[Dennis Filder <d.filder@web.de>]

Control: tag -1 patch

The attached patch should fix this by loading a more permissive policy.

Regards,
Dennis Filder.

Description: Override overly strict ImageMagick coder policy (#987504)
 This creates a more permissive version of
 /etc/ImageMagick-6/policy.xml and ensures it gets loaded after the
 one from /etc.
 .
 It is done by means of a patch to make use of the debhelper-provided
 $HOME visible by dh_auto_*.
 .
 The relevant code is at:
 https://sources.debian.org/src/imagemagick/8:6.9.11.60+dfsg-1.3/magick/configure.c/#L860
Author: Dennis Filder <d.filder@web.de>
Last-Updated: 2021-07-15
--- a/generate.sh
+++ b/generate.sh
@@ -33,6 +33,29 @@
 generate XML '1.0' xml10
 generate XML '1.1' xml11
 
+# this relies on debhelper providing a $HOME directory for us to write
+# to
+polfile="/etc/$(convert -version|sed -n '/^Version: /s@Version: ImageMagick \([[:digit:]]\+\)\..*@ImageMagick-\1@p')"/policy.xml
+if [ ! -f "$polfile" ]; then
+    echo "Error: generate.sh: Policy file not found: $polfile" >&2;
+    exit 1
+fi
+if [ -e "$HOME"/.magick ]; then
+    rm -Rf "$HOME"/.magick
+fi;
+if [ -e "$HOME"/.magick ]; then
+    echo "Error: generate.sh: Failed to remove $HOME/.magick -- remove manually and try again." >&2;
+    exit 1
+fi
+mkdir "$HOME"/.magick
+if [ ! -d "$HOME"/.magick ]; then
+    echo "Error: generate.sh: Failed to create $HOME/.magick -- investigate, fix manually, then try again." >&2;
+    exit 1;
+fi
+
+sed -e '/<policy domain="coder" rights="none" pattern="EPS" .>/s@"none"@"read|write"@' "$polfile" \
+    > "$HOME"/.magick/policy.xml
+
 /bin/ls Icons/*.svg | sed 's/-v\.svg//' | xargs -I{} convert -background none {}-v.svg {}.png
 /bin/ls Icons/*.svg | sed 's/-v\.svg//' | xargs -I{} convert -background none {}-v.svg {}.gif
 /bin/ls Icons/*.svg | sed 's/-v\.svg//' | xargs -I{} convert -background none {}-v.svg {}-v.eps