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 61d26c515f9cce531653bee28195adfc4df7ded5..0e656b22884d9bf91da27fabc684cdbce3112719 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.46 2007/07/13 03:43:23 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.47 2007/09/23 21:36:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -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));
 }