From e5605e92924b0055da19905d761919e3011c29a3 Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@keybit.net>
Date: Tue, 14 Apr 2015 11:26:05 +0200
Subject: [PATCH] Fix crash in schema parser

Closes #71.
Includes testcase.
---
 lib/pc_schema.c           | 7 -------
 pgsql/Makefile            | 2 +-
 pgsql/expected/schema.out | 8 ++++++++
 pgsql/sql/schema.sql      | 2 ++
 4 files changed, 11 insertions(+), 8 deletions(-)
 create mode 100644 pgsql/expected/schema.out
 create mode 100644 pgsql/sql/schema.sql

diff --git a/lib/pc_schema.c b/lib/pc_schema.c
index b800c17..98e459f 100644
--- a/lib/pc_schema.c
+++ b/lib/pc_schema.c
@@ -402,7 +402,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 	xml_doc = xmlReadMemory(xml_ptr, xml_size, NULL, NULL, 0);
 	if ( ! xml_doc )
 	{
-		xmlCleanupParser();
 		pcwarn("unable to parse schema XML");
 		return PC_FAILURE;
 	}
@@ -417,7 +416,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 	if( ! xpath_ctx )
 	{
 		xmlFreeDoc(xml_doc);
-		xmlCleanupParser();
 		pcwarn("unable to create new XPath context to read schema XML");
 		return PC_FAILURE;
 	}
@@ -432,7 +430,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 	{
 		xmlXPathFreeContext(xpath_ctx);
 		xmlFreeDoc(xml_doc);
-		xmlCleanupParser();
 		pcwarn("unable to evaluate xpath expression \"%s\" against schema XML", xpath_str);
 		return PC_FAILURE;
 	}
@@ -512,7 +509,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 						xmlXPathFreeObject(xpath_obj);
 						xmlXPathFreeContext(xpath_ctx);
 						xmlFreeDoc(xml_doc);
-						xmlCleanupParser();
 						pc_schema_free(s);
 						pcwarn("schema dimension at position \"%d\" is declared twice", d->position + 1, ndims);
 						return PC_FAILURE;
@@ -532,7 +528,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 					xmlXPathFreeObject(xpath_obj);
 					xmlXPathFreeContext(xpath_ctx);
 					xmlFreeDoc(xml_doc);
-					xmlCleanupParser();
 					pc_schema_free(s);
 					pcwarn("schema dimension states position \"%d\", but number of XML dimensions is \"%d\"", d->position + 1, ndims);
 					return PC_FAILURE;
@@ -554,7 +549,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 	{
 		xmlXPathFreeContext(xpath_ctx);
 		xmlFreeDoc(xml_doc);
-		xmlCleanupParser();
 		pcwarn("unable to evaluate xpath expression \"%s\" against schema XML", xpath_metadata_str);
 		return PC_FAILURE;
 	}
@@ -594,7 +588,6 @@ pc_schema_from_xml(const char *xml_str, PCSCHEMA **schema)
 
 	xmlXPathFreeContext(xpath_ctx);
 	xmlFreeDoc(xml_doc);
-	xmlCleanupParser();
 
 	return PC_SUCCESS;
 }
diff --git a/pgsql/Makefile b/pgsql/Makefile
index 7b5492a..44c40cc 100644
--- a/pgsql/Makefile
+++ b/pgsql/Makefile
@@ -24,7 +24,7 @@ DATA_built = \
   $(EXTENSION)--$(EXTVERSION).sql \
   $(UPGRADES)
 
-REGRESS = pointcloud pointcloud_columns
+REGRESS = pointcloud pointcloud_columns schema
 
 ifneq ($(GHT_LDFLAGS),)
 REGRESS += pointcloud-ght
diff --git a/pgsql/expected/schema.out b/pgsql/expected/schema.out
new file mode 100644
index 0000000..3b1a726
--- /dev/null
+++ b/pgsql/expected/schema.out
@@ -0,0 +1,8 @@
+-- See https://github.com/pgpointcloud/pointcloud/issues/71
+select '#71', PC_SchemaIsValid('<xml/>'::xml::text);
+WARNING:  unable to evaluate xpath expression "/pc:PointCloudSchema/pc:dimension" against schema XML
+ ?column? | pc_schemaisvalid 
+----------+------------------
+ #71      | f
+(1 row)
+
diff --git a/pgsql/sql/schema.sql b/pgsql/sql/schema.sql
new file mode 100644
index 0000000..34a1133
--- /dev/null
+++ b/pgsql/sql/schema.sql
@@ -0,0 +1,2 @@
+-- See https://github.com/pgpointcloud/pointcloud/issues/71
+select '#71', PC_SchemaIsValid('<xml/>'::xml::text);