This patch fixes a crash in the libxml2 bindings for Python 3.x
that 'itstool' stumbles upon when processing UTF-8 data:

  https://issues.guix.gnu.org/issue/37468

Patch by Jan Matejek
from <https://bugzilla.opensuse.org/show_bug.cgi?id=1065270>.

--- libxml2-2.9.5.orig/python/libxml.c
+++ libxml2-2.9.5/python/libxml.c
@@ -1620,6 +1620,7 @@ libxml_xmlErrorFuncHandler(ATTRIBUTE_UNU
     PyObject *message;
     PyObject *result;
     char str[1000];
+    unsigned char *ptr = (unsigned char *)str;
 
 #ifdef DEBUG_ERROR
     printf("libxml_xmlErrorFuncHandler(%p, %s, ...) called\n", ctx, msg);
@@ -1636,12 +1637,20 @@ libxml_xmlErrorFuncHandler(ATTRIBUTE_UNU
 	    str[999] = 0;
         va_end(ap);
 
+#if PY_MAJOR_VERSION >= 3
+        /* Ensure the error string doesn't start at UTF8 continuation. */
+        while (*ptr && (*ptr & 0xc0) == 0x80)
+            ptr++;
+#endif
+
         list = PyTuple_New(2);
         PyTuple_SetItem(list, 0, libxml_xmlPythonErrorFuncCtxt);
         Py_XINCREF(libxml_xmlPythonErrorFuncCtxt);
-        message = libxml_charPtrConstWrap(str);
+        message = libxml_charPtrConstWrap(ptr);
         PyTuple_SetItem(list, 1, message);
         result = PyEval_CallObject(libxml_xmlPythonErrorFuncHandler, list);
+        /* Forget any errors caused in the error handler. */
+        PyErr_Clear();
         Py_XDECREF(list);
         Py_XDECREF(result);
     }
4a3e5a5e4b5020aa1906a7c635'>commit</a><a href='/guix/diff/gnu/tests/reconfigure.scm?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/tests/reconfigure.scm'>
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<div class='path'>path: <a href='/guix/log/?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635'>root</a>/<a href='/guix/log/gnu?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635'>gnu</a>/<a href='/guix/log/gnu/tests?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635'>tests</a>/<a href='/guix/log/gnu/tests/reconfigure.scm?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635'>reconfigure.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/tests/reconfigure.scm?id=30da7825aac8474a3e5a5e4b5020aa1906a7c635&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-04-08 00:05:48 +0200'>2024-04-08</span></td><td><a href='/guix/commit/gnu/tests/reconfigure.scm?id=a7f15c9ecffc1762f5886fb5a2a14490e2994c8c'>reconfigure: /run/current-system points to generation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/scripts/system/reconfigure.scm (switch-system-program): Set
‘GUIX_NEW_SYSTEM’ to GENERATION rather than OS, for consistency with
what ‘boot-system’ does.
* gnu/tests/reconfigure.scm (run-switch-to-system-test)
["script activated the new generation"]: Adjust accordingly.

Change-Id: I57b693606a41b8c952df32bbdc2b9120c6dbfd6a
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-05-06 17:12:45 +0200'>2023-05-06</span></td><td><a href='/guix/commit/gnu/tests/reconfigure.scm?id=f51888272558d98cf5c196b93fb6c499056fbf6c'>tests: Add missing module imports for marionette-evaluated code.</a><span class='msg-avail'>...<span class='msg-tooltip'>This missing imports became apparent with commit
a09c7da8f8d8e732f969cf0a09aaa78f87032ab1, which runs the marionette
service in a fresh Guile process with fewer imports.

* gnu/tests/databases.scm (run-postgresql-test, run-timescaledb-test)
(run-mysql-test): Add missing module imports for code passed to
'marionette-eval'.
* gnu/tests/docker.scm (run-docker-test, run-docker-system-test): Likewise.
* gnu/tests/mail.scm (run-dovecot-test, run-getmail-test): Likewise.
* gnu/tests/monitoring.scm (run-zabbix-server-test): Likewise.
* gnu/tests/pam.scm (run-test-pam-limits): Likewise.
* gnu/tests/reconfigure.scm (run-switch-to-system-test)
(run-install-bootloader-test): Likewise.
* gnu/tests/security-token.scm (run-pcscd-test): Likewise.
* gnu/tests/install.scm (gui-test-program): Likewise.
* gnu/tests/telephony.scm (run-jami-test): Add modules to
the #:imported-modules argument of 'marionette-operating-system'.
[test]: Remove them from 'with-imported-modules'; remove
'with-extensions'.  Add "d-bus tooling loaded" test to set up %load-path
and %load-compiled-path so the marionette process can find
guile-ac-d-bus and guile-packrat.
</span></span></td><td>Ludovic Courtès</td></tr>