Defend against null error message reported by libxml2.

While this isn't really supposed to happen, it can occur in OOM
situations and perhaps others.  Instead of crashing, substitute
"(no message provided)".

I didn't worry about localizing this text, since we aren't
localizing anything else here; besides, if we're on the edge of
OOM, it's unlikely gettext() would work.

Report and fix by Sergio Conde Gómez in bug #15624.

Discussion: https://postgr.es/m/15624-4dea54091a2864e6@postgresql.org

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 96f187c6ef4fc4cca16c8315cdc3d016aa0c0149..8b0d9f7181cb89dc5e9620c958625d2a67e0288f 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1640,7 +1640,10 @@ xml_errorHandler(void *data, xmlErrorPtr error)
        appendStringInfo(errorBuf, "line %d: ", error->line);
    if (name != NULL)
        appendStringInfo(errorBuf, "element %s: ", name);
-   appendStringInfoString(errorBuf, error->message);
+   if (error->message != NULL)
+       appendStringInfoString(errorBuf, error->message);
+   else
+       appendStringInfoString(errorBuf, "(no message provided)");
 
    /*
     * Append context information to errorBuf.