Fix bugs in XML binary I/O functions. Heikki and Tom

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index f2b672b9b0986e1809a7aa47eea5e468a3a703f1..86a9aad19806b6bbebc8b2966a385c986acdd9c7 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -232,37 +232,51 @@ xml_recv(PG_FUNCTION_ARGS)
        xmlDocPtr       doc;
        xmlChar    *encoding = NULL;
 
-       str = pq_getmsgtext(buf, buf->len - buf->cursor, &nbytes);
+       /*
+        * Read the data in raw format. We don't know yet what the encoding
+        * is, as that information is embedded in the xml declaration; so we
+        * have to parse that before converting to server encoding.
+        */
+       nbytes = buf->len - buf->cursor;
+       str = (char *) pq_getmsgbytes(buf, nbytes);
 
-       result = palloc(nbytes + VARHDRSZ);
+       /*
+        * We need a null-terminated string to pass to parse_xml_decl().  Rather
+        * than make a separate copy, make the temporary result one byte bigger
+        * than it needs to be.
+        */
+       result = palloc(nbytes + 1 + VARHDRSZ);
        SET_VARSIZE(result, nbytes + VARHDRSZ);
        memcpy(VARDATA(result), str, nbytes);
+       str = VARDATA(result);
+       str[nbytes] = '\0';
 
        parse_xml_decl((xmlChar *) str, NULL, NULL, &encoding, NULL);
 
        /*
         * Parse the data to check if it is well-formed XML data.  Assume
-        * that ERROR occurred if parsing failed.
+        * that xml_parse will throw ERROR if not.
         */
        doc = xml_parse(result, xmloption, true, encoding);
        xmlFreeDoc(doc);
 
+       /* Now that we know what we're dealing with, convert to server encoding */
        newstr = (char *) pg_do_encoding_conversion((unsigned char *) str,
                                                                                                nbytes,
                                                                                                encoding ? pg_char_to_encoding((char *) encoding) : PG_UTF8,
                                                                                                GetDatabaseEncoding());
 
-       pfree(str);
-
        if (newstr != str)
        {
-               free(result);
+               pfree(result);
 
                nbytes = strlen(newstr);
 
                result = palloc(nbytes + VARHDRSZ);
                SET_VARSIZE(result, nbytes + VARHDRSZ);
                memcpy(VARDATA(result), newstr, nbytes);
+
+               pfree(newstr);
        }
 
        PG_RETURN_XML_P(result);
@@ -277,11 +291,18 @@ Datum
 xml_send(PG_FUNCTION_ARGS)
 {
        xmltype    *x = PG_GETARG_XML_P(0);
-       char       *outval = xml_out_internal(x, pg_get_client_encoding());
+       char       *outval;
        StringInfoData buf;
+       
+       /*
+        * xml_out_internal doesn't convert the encoding, it just prints
+        * the right declaration. pq_sendtext will do the conversion.
+        */
+       outval = xml_out_internal(x, pg_get_client_encoding());
 
        pq_begintypsend(&buf);
-       pq_sendstring(&buf, outval);
+       pq_sendtext(&buf, outval, strlen(outval));
+       pfree(outval);
        PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }