bug#27563: [PATCH v4 2/3] gnu: ghostscript: Make XMP UUID headers optional, depending on environment variable.

[Danny Milosavljevic]

* gnu/packages/patches/ghostscript-no-header-uuid.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/ghostscript.scm (ghostscript): Use it.
---
 gnu/local.mk                                       |  1 +
 gnu/packages/ghostscript.scm                       |  3 +-
 .../patches/ghostscript-no-header-uuid.patch       | 43 ++++++++++++++++++++++
 3 files changed, 46 insertions(+), 1 deletion(-)
 create mode 100644 gnu/packages/patches/ghostscript-no-header-uuid.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index 8cbded44e..9cf4648aa 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -620,6 +620,7 @@ dist_patch_DATA =                                           
\
   %D%/packages/patches/ghc-dont-pass-linker-flags-via-response-files.patch     
\
   %D%/packages/patches/ghostscript-CVE-2017-8291.patch         \
   %D%/packages/patches/ghostscript-no-header-id.patch          \
+  %D%/packages/patches/ghostscript-no-header-uuid.patch                \
   %D%/packages/patches/ghostscript-runpath.patch               \
   %D%/packages/patches/glib-networking-ssl-cert-file.patch     \
   %D%/packages/patches/glib-tests-timer.patch                  \
diff --git a/gnu/packages/ghostscript.scm b/gnu/packages/ghostscript.scm
index af565f3e3..3a84db3e4 100644
--- a/gnu/packages/ghostscript.scm
+++ b/gnu/packages/ghostscript.scm
@@ -144,7 +144,8 @@ printing, and psresize, for adjusting page sizes.")
           "0lyhjcrkmd5fcmh8h56bs4xr9k4jasmikv5vsix1hd4ai0ad1q9b"))
         (patches (search-patches "ghostscript-runpath.patch"
                                  "ghostscript-CVE-2017-8291.patch"
-                                 "ghostscript-no-header-id.patch"))
+                                 "ghostscript-no-header-id.patch"
+                                 "ghostscript-no-header-uuid.patch"))
         (modules '((guix build utils)))
         (snippet
           ;; Remove bundled libraries. The bundled OpenJPEG is a patched fork 
so
diff --git a/gnu/packages/patches/ghostscript-no-header-uuid.patch 
b/gnu/packages/patches/ghostscript-no-header-uuid.patch
new file mode 100644
index 000000000..53bef90f0
--- /dev/null
+++ b/gnu/packages/patches/ghostscript-no-header-uuid.patch
@@ -0,0 +1,43 @@
+This patch makes the UUIDs in the XMP header optional, depending on the
+setting of the environment variable GS_GENERATE_UUIDS.
+
+diff -ur orig/gnu-ghostscript-9.14.0/devices/vector/gdevpdfe.c 
aa/gnu-ghostscript-9.14.0/devices/vector/gdevpdfe.c
+--- orig/gnu-ghostscript-9.14.0/devices/vector/gdevpdfe.c      2017-07-09 
23:30:28.960479189 +0200
++++ gnu-ghostscript-9.14.0/devices/vector/gdevpdfe.c   2017-07-10 
01:04:12.252478276 +0200
+@@ -617,7 +617,7 @@
+         return code;
+ 
+     /* PDF/A XMP reference recommends setting UUID to empty. If not empty 
must be a URI */
+-    if (pdev->PDFA != 0)
++    if (pdev->PDFA != 0 || (getenv("GS_GENERATE_UUIDS") && 
(strcmp(getenv("GS_GENERATE_UUIDS"), "0") == 0 || 
strcmp(getenv("GS_GENERATE_UUIDS"), "no") == 0)))
+         instance_uuid[0] = 0x00;
+ 
+     cre_date_time_len = pdf_get_docinfo_item(pdev, "/CreationDate", 
cre_date_time, sizeof(cre_date_time));
+@@ -719,15 +719,18 @@
+             pdf_xml_tag_close(s, "rdf:Description");
+             pdf_xml_newline(s);
+ 
+-            pdf_xml_tag_open_beg(s, "rdf:Description");
+-            pdf_xml_attribute_name(s, "rdf:about");
+-            pdf_xml_attribute_value(s, instance_uuid);
+-            pdf_xml_attribute_name(s, "xmlns:xapMM");
+-            pdf_xml_attribute_value(s, "http://ns.adobe.com/xap/1.0/mm/";);
+-            pdf_xml_attribute_name(s, "xapMM:DocumentID");
+-            pdf_xml_attribute_value(s, document_uuid);
+-            pdf_xml_tag_end_empty(s);
+-            pdf_xml_newline(s);
++            if (!getenv("GS_GENERATE_UUIDS") || 
(strcmp(getenv("GS_GENERATE_UUIDS"), "0") != 0 && 
strcmp(getenv("GS_GENERATE_UUIDS"), "no") != 0))
++            {
++                pdf_xml_tag_open_beg(s, "rdf:Description");
++                pdf_xml_attribute_name(s, "rdf:about");
++                pdf_xml_attribute_value(s, instance_uuid);
++                pdf_xml_attribute_name(s, "xmlns:xapMM");
++                pdf_xml_attribute_value(s, "http://ns.adobe.com/xap/1.0/mm/";);
++                pdf_xml_attribute_name(s, "xapMM:DocumentID");
++                pdf_xml_attribute_value(s, document_uuid);
++                pdf_xml_tag_end_empty(s);
++                pdf_xml_newline(s);
++            }
+ 
+             pdf_xml_tag_open_beg(s, "rdf:Description");
+             pdf_xml_attribute_name(s, "rdf:about");