Allow empty content in xml type

The xml type previously rejected "content" that is empty or consists
only of spaces.  But the SQL/XML standard allows that, so change that.
The accepted values for XML "documents" are not changed.

Reviewed-by: Ali Akbar <the.apaan@gmail.com>

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 422be69bd6d912a8449a2bb38800b6f44b0b8d54..119dfc7efecc6990cde092982bac366cc604043d 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1400,11 +1400,15 @@ xml_parse(text *data, XmlOptionType xmloption_arg, bool preserve_whitespace,
            doc->encoding = xmlStrdup((const xmlChar *) "UTF-8");
            doc->standalone = standalone;
 
-           res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0,
-                                                  utf8string + count, NULL);
-           if (res_code != 0 || xmlerrcxt->err_occurred)
-               xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_XML_CONTENT,
-                           "invalid XML content");
+           /* allow empty content */
+           if (*(utf8string + count))
+           {
+               res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0,
+                                                      utf8string + count, NULL);
+               if (res_code != 0 || xmlerrcxt->err_occurred)
+                   xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_XML_CONTENT,
+                               "invalid XML content");
+           }
        }
    }
    PG_CATCH();

diff --git a/src/test/regress/expected/xml.out b/src/test/regress/expected/xml.out
index 382f9df5093157f85351067fbf498bb18e2befa0..6e6c673dac591b1bd58efe92e373c911b16757e2 100644 (file)
--- a/src/test/regress/expected/xml.out
+++ b/src/test/regress/expected/xml.out
@@ -194,6 +194,18 @@ SELECT xmlelement(name foo, xmlattributes('<>&"''' as funny, xml 'b<a/>r' as fun
  <foo funny="&lt;&gt;&amp;&quot;'" funnier="b&lt;a/&gt;r"/>
 (1 row)
 
+SELECT xmlparse(content '');
+ xmlparse 
+----------
+ 
+(1 row)
+
+SELECT xmlparse(content '  ');
+ xmlparse 
+----------
+   
+(1 row)
+
 SELECT xmlparse(content 'abc');
  xmlparse 
 ----------
@@ -251,6 +263,22 @@ SELECT xmlparse(content '<nosuchprefix:tag/>');
  <nosuchprefix:tag/>
 (1 row)
 
+SELECT xmlparse(document '');
+ERROR:  invalid XML document
+DETAIL:  line 1: switching encoding : no input
+
+^
+line 1: Document is empty
+
+^
+line 1: Start tag expected, '<' not found
+
+^
+SELECT xmlparse(document '   ');
+ERROR:  invalid XML document
+DETAIL:  line 1: Start tag expected, '<' not found
+   
+   ^
 SELECT xmlparse(document 'abc');
 ERROR:  invalid XML document
 DETAIL:  line 1: Start tag expected, '<' not found

diff --git a/src/test/regress/expected/xml_1.out b/src/test/regress/expected/xml_1.out
index a34d1f41dd664cf8627cae2ccf254373d743c336..b0e00671e8b2089ac759c4a81b0edca9b729caef 100644 (file)
--- a/src/test/regress/expected/xml_1.out
+++ b/src/test/regress/expected/xml_1.out
@@ -164,6 +164,14 @@ SELECT xmlelement(name foo, xmlattributes('<>&"''' as funny, xml 'b<a/>r' as fun
 ERROR:  unsupported XML feature
 DETAIL:  This functionality requires the server to be built with libxml support.
 HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xmlparse(content '');
+ERROR:  unsupported XML feature
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xmlparse(content '  ');
+ERROR:  unsupported XML feature
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
 SELECT xmlparse(content 'abc');
 ERROR:  unsupported XML feature
 DETAIL:  This functionality requires the server to be built with libxml support.
@@ -196,6 +204,14 @@ SELECT xmlparse(content '<nosuchprefix:tag/>');
 ERROR:  unsupported XML feature
 DETAIL:  This functionality requires the server to be built with libxml support.
 HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xmlparse(document '');
+ERROR:  unsupported XML feature
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xmlparse(document '   ');
+ERROR:  unsupported XML feature
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
 SELECT xmlparse(document 'abc');
 ERROR:  unsupported XML feature
 DETAIL:  This functionality requires the server to be built with libxml support.

diff --git a/src/test/regress/sql/xml.sql b/src/test/regress/sql/xml.sql
index 90d4d67f04e289f9bee569c7c8eb349881d840a1..922ab7a604a3f99278e70113050ba1df32e1db62 100644 (file)
--- a/src/test/regress/sql/xml.sql
+++ b/src/test/regress/sql/xml.sql
@@ -60,6 +60,8 @@ SELECT xmlelement(name foo, xmlattributes('infinity'::timestamp as bar));
 SELECT xmlelement(name foo, xmlattributes('<>&"''' as funny, xml 'b<a/>r' as funnier));
 
 
+SELECT xmlparse(content '');
+SELECT xmlparse(content '  ');
 SELECT xmlparse(content 'abc');
 SELECT xmlparse(content '<abc>x</abc>');
 SELECT xmlparse(content '<invalidentity>&</invalidentity>');
@@ -69,6 +71,8 @@ SELECT xmlparse(content '<relativens xmlns=''relative''/>');
 SELECT xmlparse(content '<twoerrors>&idontexist;</unbalanced>');
 SELECT xmlparse(content '<nosuchprefix:tag/>');
 
+SELECT xmlparse(document '');
+SELECT xmlparse(document '   ');
 SELECT xmlparse(document 'abc');
 SELECT xmlparse(document '<abc>x</abc>');
 SELECT xmlparse(document '<invalidentity>&</abc>');