Description:
------------
Incorrect use of OCI-Lob->close() can cause a crash.  The crash is
ultimately due to Oracle bug 6786812 and is related to thread
handling.

It reproduces with PHP 5.3 (after DRCP support was added). It is
likely to reproduce in threaded builds of PHP 5.x on Windows.

There is a code workaround below, but because this might add to the
roundtrip count in the general case, I'd like to investigate other
solutions.

--- oci8_lob.c	24 Jan 2008 14:09:36 -0000	1.7.2.6.2.14.2.3
+++ oci8_lob.c	31 Jan 2008 21:27:10 -0000
@@ -570,13 +570,17 @@
int php_oci_lob_close (php_oci_descriptor *descriptor TSRMLS_DC)
{
php_oci_connection *connection = descriptor->connection;
-	
-	PHP_OCI_CALL_RETURN(connection->errcode, OCILobClose, (connection->svc, connection->err, descriptor->descriptor));
+	boolean flag = 0;
 
-	if (connection->errcode != OCI_SUCCESS) {
-		php_oci_error(connection->err, connection->errcode TSRMLS_CC);
-		PHP_OCI_HANDLE_ERROR(connection, connection->errcode);
-		return 1;
+	PHP_OCI_CALL_RETURN(connection->errcode, OCILobIsOpen, (connection->svc, connection->err, descriptor->descriptor, &flag));
+	if (connection->errcode == OCI_SUCCESS && flag) {
+		PHP_OCI_CALL_RETURN(connection->errcode, OCILobClose, (connection->svc, connection->err, descriptor->descriptor));
+		
+		if (connection->errcode != OCI_SUCCESS) {
+			php_oci_error(connection->err, connection->errcode TSRMLS_CC);
+			PHP_OCI_HANDLE_ERROR(connection, connection->errcode);
+			return 1;
+		}
}

Reproduce code:
---------------
<?php

$c = oci_connect('hr', 'hrpwd', '//ca-tools1/XE');

$stmtarray = array(
    "create or replace procedure ctest (p in out clob)
    as begin p := 'A'; end;"
);

foreach ($stmtarray as $stmt) {
    $s = oci_parse($c, $stmt);
    @oci_execute($s);
}

$stmt = oci_parse($c,'begin ctest(:c_data); end;');
$textLob = oci_new_descriptor($c, OCI_D_LOB);
oci_bind_by_name($stmt, ":c_data", $textLob, -1, OCI_B_CLOB);
oci_execute($stmt, OCI_DEFAULT);
$r = $textLob->load();
echo $r;

// Incorrectly closing the lob causes a crash.  OCI-LOB->close() is
// documented for use only with OCI-Lob->writeTemporary()
$textLob->close();

print "ok\n";

?>