* XML data type support.
*
*
- * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.22 2007/01/25 11:53:51 petere Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.76 2008/08/25 22:42:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
* fail. For one thing, this avoids having to manage variant catalog
* installations. But it also has nice effects such as that you can
* dump a database containing XML type data even if the server is not
- * linked with libxml. Thus, make sure xml_out() works even if nothing
+ * linked with libxml. Thus, make sure xml_out() works even if nothing
* else does.
*/
+/*
+ * Notes on memory management:
+ *
+ * Via callbacks, libxml is told to use palloc and friends for memory
+ * management, within a context that we reset at transaction end (and also at
+ * subtransaction abort) to prevent memory leaks. Resetting at transaction or
+ * subtransaction abort is necessary since we might have thrown a longjmp
+ * while some data structures were not linked from anywhere persistent.
+ * Resetting at transaction commit might not be necessary, but seems a good
+ * idea to forestall long-term leaks.
+ *
+ * Sometimes libxml allocates global structures in the hope that it can reuse
+ * them later on. Therefore, before resetting LibxmlContext, we must tell
+ * libxml to discard any global data it has. The libxml API documentation is
+ * not very good about specifying this, but for now we assume that
+ * xmlCleanupParser() will get rid of anything we need to worry about.
+ *
+ * We use palloc --- which will throw a longjmp on error --- for allocation
+ * callbacks that officially should act like malloc, ie, return NULL on
+ * out-of-memory. This is a bit risky since there is a chance of leaving
+ * persistent libxml data structures in an inconsistent partially-constructed
+ * state, perhaps leading to crash in xmlCleanupParser(). However, as of
+ * early 2008 it is *known* that libxml can crash on out-of-memory due to
+ * inadequate checks for NULL returns, so this behavior seems the lesser
+ * of two evils.
+ */
+
#include "postgres.h"
#ifdef USE_LIBXML
#include <libxml/tree.h>
#include <libxml/uri.h>
#include <libxml/xmlerror.h>
-#include <libxml/xmlsave.h>
#include <libxml/xmlwriter.h>
-#endif /* USE_LIBXML */
+#include <libxml/xpath.h>
+#include <libxml/xpathInternals.h>
+#endif /* USE_LIBXML */
+#include "catalog/namespace.h"
#include "catalog/pg_type.h"
+#include "commands/dbcommands.h"
#include "executor/executor.h"
+#include "executor/spi.h"
#include "fmgr.h"
+#include "lib/stringinfo.h"
#include "libpq/pqformat.h"
#include "mb/pg_wchar.h"
+#include "miscadmin.h"
#include "nodes/execnodes.h"
-#include "parser/parse_expr.h"
+#include "nodes/nodeFuncs.h"
#include "utils/array.h"
#include "utils/builtins.h"
+#include "utils/date.h"
+#include "utils/datetime.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/xml.h"
+/* GUC variables */
+int xmlbinary;
+int xmloption;
+
#ifdef USE_LIBXML
static StringInfo xml_err_buf = NULL;
-
-static void xml_init(void);
-#ifdef NOT_USED
-static void *xml_palloc(size_t size);
-static void *xml_repalloc(void *ptr, size_t size);
-static void xml_pfree(void *ptr);
-static char *xml_pstrdup(const char *string);
-#endif
-static void xml_ereport(int level, int sqlcode,
- const char *msg);
-static void xml_errorHandler(void *ctxt, const char *msg, ...);
-static void xml_ereport_by_code(int level, int sqlcode,
- const char *msg, int errcode);
+static MemoryContext LibxmlContext = NULL;
+
+static void xml_init(void);
+static void xml_memory_init(void);
+static void xml_memory_cleanup(void);
+static void *xml_palloc(size_t size);
+static void *xml_repalloc(void *ptr, size_t size);
+static void xml_pfree(void *ptr);
+static char *xml_pstrdup(const char *string);
+static void xml_ereport(int level, int sqlcode, const char *msg);
+static void xml_errorHandler(void *ctxt, const char *msg,...);
+static void xml_ereport_by_code(int level, int sqlcode,
+ const char *msg, int errcode);
static xmlChar *xml_text2xmlChar(text *in);
-static int parse_xml_decl(const xmlChar *str, size_t *lenp, xmlChar **version, xmlChar **encoding, int *standalone);
-static bool print_xml_decl(StringInfo buf, const xmlChar *version, pg_enc encoding, int standalone);
-static xmlDocPtr xml_parse(text *data, bool is_document, bool preserve_whitespace, xmlChar *encoding);
-
-#endif /* USE_LIBXML */
-
-XmlBinaryType xmlbinary;
-XmlOptionType xmloption;
-
+static int parse_xml_decl(const xmlChar * str, size_t *lenp,
+ xmlChar ** version, xmlChar ** encoding, int *standalone);
+static bool print_xml_decl(StringInfo buf, const xmlChar * version,
+ pg_enc encoding, int standalone);
+static xmlDocPtr xml_parse(text *data, XmlOptionType xmloption_arg,
+ bool preserve_whitespace, xmlChar * encoding);
+static text *xml_xmlnodetoxmltype(xmlNodePtr cur);
+#endif /* USE_LIBXML */
+
+static StringInfo query_to_xml_internal(const char *query, char *tablename,
+ const char *xmlschema, bool nulls, bool tableforest,
+ const char *targetns, bool top_level);
+static const char *map_sql_table_to_xmlschema(TupleDesc tupdesc, Oid relid,
+ bool nulls, bool tableforest, const char *targetns);
+static const char *map_sql_schema_to_xmlschema_types(Oid nspid,
+ List *relid_list, bool nulls,
+ bool tableforest, const char *targetns);
+static const char *map_sql_catalog_to_xmlschema_types(List *nspid_list,
+ bool nulls, bool tableforest,
+ const char *targetns);
+static const char *map_sql_type_to_xml_name(Oid typeoid, int typmod);
+static const char *map_sql_typecoll_to_xmlschema_types(List *tupdesc_list);
+static const char *map_sql_type_to_xmlschema_type(Oid typeoid, int typmod);
+static void SPI_sql_row_to_xmlelement(int rownum, StringInfo result,
+ char *tablename, bool nulls, bool tableforest,
+ const char *targetns, bool top_level);
#define NO_XML_SUPPORT() \
ereport(ERROR, \
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), \
- errmsg("no XML support in this installation")))
+ errmsg("unsupported XML feature"), \
+ errdetail("This functionality requires the server to be built with libxml support."), \
+ errhint("You need to rebuild PostgreSQL using --with-libxml.")))
+
+
+/* from SQL/XML:2003 section 4.7 */
+#define NAMESPACE_XSD "http://www.w3.org/2001/XMLSchema"
+#define NAMESPACE_XSI "http://www.w3.org/2001/XMLSchema-instance"
+#define NAMESPACE_SQLXML "http://standards.iso.org/iso/9075/2003/sqlxml"
+
+
+#ifdef USE_LIBXML
+
+static int
+xmlChar_to_encoding(xmlChar * encoding_name)
+{
+ int encoding = pg_char_to_encoding((char *) encoding_name);
+
+ if (encoding < 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("invalid encoding name \"%s\"",
+ (char *) encoding_name)));
+ return encoding;
+}
+#endif
+/*
+ * xml_in uses a plain C string to VARDATA conversion, so for the time being
+ * we use the conversion function for the text datatype.
+ *
+ * This is only acceptable so long as xmltype and text use the same
+ * representation.
+ */
Datum
xml_in(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
- char *s = PG_GETARG_CSTRING(0);
- size_t len;
- xmltype *vardata;
- xmlDocPtr doc;
+ char *s = PG_GETARG_CSTRING(0);
+ xmltype *vardata;
+ xmlDocPtr doc;
- len = strlen(s);
- vardata = palloc(len + VARHDRSZ);
- VARATT_SIZEP(vardata) = len + VARHDRSZ;
- memcpy(VARDATA(vardata), s, len);
+ vardata = (xmltype *) cstring_to_text(s);
/*
- * Parse the data to check if it is well-formed XML data. Assume
- * that ERROR occurred if parsing failed.
+ * Parse the data to check if it is well-formed XML data. Assume that
+ * ERROR occurred if parsing failed.
*/
- doc = xml_parse(vardata, (xmloption == XMLOPTION_DOCUMENT), true, NULL);
+ doc = xml_parse(vardata, xmloption, true, NULL);
xmlFreeDoc(doc);
PG_RETURN_XML_P(vardata);
#define PG_XML_DEFAULT_VERSION "1.0"
+/*
+ * xml_out_internal uses a plain VARDATA to C string conversion, so for the
+ * time being we use the conversion function for the text datatype.
+ *
+ * This is only acceptable so long as xmltype and text use the same
+ * representation.
+ */
static char *
xml_out_internal(xmltype *x, pg_enc target_encoding)
{
- char *str;
+ char *str;
size_t len;
+
#ifdef USE_LIBXML
- xmlChar *version;
- xmlChar *encoding;
+ xmlChar *version;
+ xmlChar *encoding;
int standalone;
int res_code;
#endif
- len = VARSIZE(x) - VARHDRSZ;
- str = palloc(len + 1);
- memcpy(str, VARDATA(x), len);
- str[len] = '\0';
+ str = text_to_cstring((text *) x);
+ len = strlen(str);
#ifdef USE_LIBXML
- if ((res_code = parse_xml_decl((xmlChar *) str, &len, &version, &encoding, &standalone)) == 0)
+ if ((res_code = parse_xml_decl((xmlChar *) str,
+ &len, &version, &encoding, &standalone)) == 0)
{
StringInfoData buf;
if (!print_xml_decl(&buf, version, target_encoding, standalone))
{
/*
- * If we are not going to produce an XML declaration, eat
- * a single newline in the original string to prevent
- * empty first lines in the output.
+ * If we are not going to produce an XML declaration, eat a single
+ * newline in the original string to prevent empty first lines in
+ * the output.
*/
if (*(str + len) == '\n')
len += 1;
}
xml_ereport_by_code(WARNING, ERRCODE_INTERNAL_ERROR,
- "could not parse XML declaration in stored value", res_code);
+ "could not parse XML declaration in stored value",
+ res_code);
#endif
return str;
}
Datum
xml_out(PG_FUNCTION_ARGS)
{
- xmltype *x = PG_GETARG_XML_P(0);
+ xmltype *x = PG_GETARG_XML_P(0);
/*
- * xml_out removes the encoding property in all cases. This is
- * because we cannot control from here whether the datum will be
- * converted to a different client encoding, so we'd do more harm
- * than good by including it.
+ * xml_out removes the encoding property in all cases. This is because we
+ * cannot control from here whether the datum will be converted to a
+ * different client encoding, so we'd do more harm than good by including
+ * it.
*/
PG_RETURN_CSTRING(xml_out_internal(x, 0));
}
{
#ifdef USE_LIBXML
StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
- xmltype *result;
+ xmltype *result;
char *str;
char *newstr;
int nbytes;
xmlDocPtr doc;
- xmlChar *encoding = NULL;
+ 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);
- VARATT_SIZEP(result) = 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.
+ * Parse the data to check if it is well-formed XML data. Assume that
+ * xml_parse will throw ERROR if not.
*/
- doc = xml_parse(result, (xmloption == XMLOPTION_DOCUMENT), true, encoding);
+ 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,
+ encoding ?
+ xmlChar_to_encoding(encoding) :
+ PG_UTF8,
GetDatabaseEncoding());
- pfree(str);
-
if (newstr != str)
{
- free(result);
-
- nbytes = strlen(newstr);
-
- result = palloc(nbytes + VARHDRSZ);
- VARATT_SIZEP(result) = nbytes + VARHDRSZ;
- memcpy(VARDATA(result), newstr, nbytes);
+ pfree(result);
+ result = (xmltype *) cstring_to_text(newstr);
+ pfree(newstr);
}
PG_RETURN_XML_P(result);
Datum
xml_send(PG_FUNCTION_ARGS)
{
- xmltype *x = PG_GETARG_XML_P(0);
- char *outval = xml_out_internal(x, pg_get_client_encoding());
+ xmltype *x = PG_GETARG_XML_P(0);
+ 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));
}
{
appendBinaryStringInfo(str, VARDATA(t), VARSIZE(t) - VARHDRSZ);
}
+#endif
static xmltype *
stringinfo_to_xmltype(StringInfo buf)
{
- int32 len;
- xmltype *result;
-
- len = buf->len + VARHDRSZ;
- result = palloc(len);
- VARATT_SIZEP(result) = len;
- memcpy(VARDATA(result), buf->data, buf->len);
-
- return result;
+ return (xmltype *) cstring_to_text_with_len(buf->data, buf->len);
}
-#ifdef NOT_USED
static xmltype *
cstring_to_xmltype(const char *string)
{
- int32 len;
- xmltype *result;
-
- len = strlen(string) + VARHDRSZ;
- result = palloc(len);
- VARATT_SIZEP(result) = len;
- memcpy(VARDATA(result), string, len - VARHDRSZ);
-
- return result;
+ return (xmltype *) cstring_to_text(string);
}
-#endif
+#ifdef USE_LIBXML
static xmltype *
xmlBuffer_to_xmltype(xmlBufferPtr buf)
{
- int32 len;
- xmltype *result;
-
- len = xmlBufferLength(buf) + VARHDRSZ;
- result = palloc(len);
- VARATT_SIZEP(result) = len;
- memcpy(VARDATA(result), xmlBufferContent(buf), len - VARHDRSZ);
-
- return result;
+ return (xmltype *) cstring_to_text_with_len((char *) xmlBufferContent(buf),
+ xmlBufferLength(buf));
}
#endif
xmlcomment(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
- text *arg = PG_GETARG_TEXT_P(0);
- int len = VARSIZE(arg) - VARHDRSZ;
+ text *arg = PG_GETARG_TEXT_P(0);
+ char *argdata = VARDATA(arg);
+ int len = VARSIZE(arg) - VARHDRSZ;
StringInfoData buf;
- int i;
+ int i;
/* check for "--" in string or "-" at the end */
for (i = 1; i < len; i++)
- if ((VARDATA(arg)[i] == '-' && VARDATA(arg)[i - 1] == '-')
- || (VARDATA(arg)[i] == '-' && i == len - 1))
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_XML_COMMENT),
- errmsg("invalid XML comment")));
+ {
+ if (argdata[i] == '-' && argdata[i - 1] == '-')
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_XML_COMMENT),
+ errmsg("invalid XML comment")));
+ }
+ if (len > 0 && argdata[len - 1] == '-')
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_XML_COMMENT),
+ errmsg("invalid XML comment")));
initStringInfo(&buf);
appendStringInfo(&buf, "<!--");
/*
* TODO: xmlconcat needs to merge the notations and unparsed entities
- * of the argument values. Not very important in practice, though.
+ * of the argument values. Not very important in practice, though.
*/
xmltype *
xmlconcat(List *args)
{
#ifdef USE_LIBXML
- StringInfoData buf;
- ListCell *v;
-
int global_standalone = 1;
- xmlChar *global_version = NULL;
+ xmlChar *global_version = NULL;
bool global_version_no_value = false;
+ StringInfoData buf;
+ ListCell *v;
initStringInfo(&buf);
foreach(v, args)
{
+ xmltype *x = DatumGetXmlP(PointerGetDatum(lfirst(v)));
size_t len;
- xmlChar *version;
+ xmlChar *version;
int standalone;
- xmltype *x = DatumGetXmlP(PointerGetDatum(lfirst(v)));
char *str;
len = VARSIZE(x) - VARHDRSZ;
- str = palloc(len + 1);
- memcpy(str, VARDATA(x), len);
- str[len] = '\0';
+ str = text_to_cstring((text *) x);
parse_xml_decl((xmlChar *) str, &len, &version, NULL, &standalone);
initStringInfo(&buf2);
print_xml_decl(&buf2,
- (!global_version_no_value && global_version) ? global_version : NULL,
+ (!global_version_no_value) ? global_version : NULL,
0,
global_standalone);
else if (PG_ARGISNULL(1))
PG_RETURN_XML_P(PG_GETARG_XML_P(0));
else
- PG_RETURN_XML_P(xmlconcat(list_make2(PG_GETARG_XML_P(0), PG_GETARG_XML_P(1))));
+ PG_RETURN_XML_P(xmlconcat(list_make2(PG_GETARG_XML_P(0),
+ PG_GETARG_XML_P(1))));
}
{
text *data = PG_GETARG_TEXT_P(0);
- PG_RETURN_XML_P(xmlparse(data, (xmloption == XMLOPTION_DOCUMENT), true));
+ PG_RETURN_XML_P(xmlparse(data, xmloption, true));
+}
+
+
+Datum
+xmltotext(PG_FUNCTION_ARGS)
+{
+ xmltype *data = PG_GETARG_XML_P(0);
+
+ /* It's actually binary compatible. */
+ PG_RETURN_TEXT_P((text *) data);
+}
+
+
+text *
+xmltotext_with_xmloption(xmltype *data, XmlOptionType xmloption_arg)
+{
+ if (xmloption_arg == XMLOPTION_DOCUMENT && !xml_is_document(data))
+ ereport(ERROR,
+ (errcode(ERRCODE_NOT_AN_XML_DOCUMENT),
+ errmsg("not an XML document")));
+
+ /* It's actually binary compatible, save for the above check. */
+ return (text *) data;
}
xmlelement(XmlExprState *xmlExpr, ExprContext *econtext)
{
#ifdef USE_LIBXML
- XmlExpr *xexpr = (XmlExpr *) xmlExpr->xprstate.expr;
+ XmlExpr *xexpr = (XmlExpr *) xmlExpr->xprstate.expr;
+ xmltype *result;
+ List *named_arg_strings;
+ List *arg_strings;
int i;
ListCell *arg;
ListCell *narg;
- bool isnull;
- xmltype *result;
- Datum value;
- char *str;
-
xmlBufferPtr buf;
xmlTextWriterPtr writer;
+ /*
+ * We first evaluate all the arguments, then start up libxml and create
+ * the result. This avoids issues if one of the arguments involves a call
+ * to some other function or subsystem that wants to use libxml on its own
+ * terms.
+ */
+ named_arg_strings = NIL;
+ i = 0;
+ foreach(arg, xmlExpr->named_args)
+ {
+ ExprState *e = (ExprState *) lfirst(arg);
+ Datum value;
+ bool isnull;
+ char *str;
+
+ value = ExecEvalExpr(e, econtext, &isnull, NULL);
+ if (isnull)
+ str = NULL;
+ else
+ str = OutputFunctionCall(&xmlExpr->named_outfuncs[i], value);
+ named_arg_strings = lappend(named_arg_strings, str);
+ i++;
+ }
+
+ arg_strings = NIL;
+ foreach(arg, xmlExpr->args)
+ {
+ ExprState *e = (ExprState *) lfirst(arg);
+ Datum value;
+ bool isnull;
+ char *str;
+
+ value = ExecEvalExpr(e, econtext, &isnull, NULL);
+ /* here we can just forget NULL elements immediately */
+ if (!isnull)
+ {
+ str = map_sql_value_to_xml_value(value,
+ exprType((Node *) e->expr));
+ arg_strings = lappend(arg_strings, str);
+ }
+ }
+
+ /* now safe to run libxml */
+ xml_init();
+
buf = xmlBufferCreate();
writer = xmlNewTextWriterMemory(buf, 0);
xmlTextWriterStartElement(writer, (xmlChar *) xexpr->name);
- i = 0;
- forboth(arg, xmlExpr->named_args, narg, xexpr->arg_names)
+ forboth(arg, named_arg_strings, narg, xexpr->arg_names)
{
- ExprState *e = (ExprState *) lfirst(arg);
- char *argname = strVal(lfirst(narg));
+ char *str = (char *) lfirst(arg);
+ char *argname = strVal(lfirst(narg));
- value = ExecEvalExpr(e, econtext, &isnull, NULL);
- if (!isnull)
+ if (str)
{
- str = OutputFunctionCall(&xmlExpr->named_outfuncs[i], value);
- xmlTextWriterWriteAttribute(writer, (xmlChar *) argname, (xmlChar *) str);
+ xmlTextWriterWriteAttribute(writer,
+ (xmlChar *) argname,
+ (xmlChar *) str);
pfree(str);
}
- i++;
}
- foreach(arg, xmlExpr->args)
+ foreach(arg, arg_strings)
{
- ExprState *e = (ExprState *) lfirst(arg);
+ char *str = (char *) lfirst(arg);
- value = ExecEvalExpr(e, econtext, &isnull, NULL);
- if (!isnull)
- xmlTextWriterWriteRaw(writer, (xmlChar *) map_sql_value_to_xml_value(value, exprType((Node *) e->expr)));
+ xmlTextWriterWriteRaw(writer, (xmlChar *) str);
}
xmlTextWriterEndElement(writer);
result = xmlBuffer_to_xmltype(buf);
xmlBufferFree(buf);
+
return result;
#else
NO_XML_SUPPORT();
xmltype *
-xmlparse(text *data, bool is_document, bool preserve_whitespace)
+xmlparse(text *data, XmlOptionType xmloption_arg, bool preserve_whitespace)
{
#ifdef USE_LIBXML
xmlDocPtr doc;
- doc = xml_parse(data, is_document, preserve_whitespace, NULL);
+ doc = xml_parse(data, xmloption_arg, preserve_whitespace, NULL);
xmlFreeDoc(doc);
return (xmltype *) data;
xmlpi(char *target, text *arg, bool arg_is_null, bool *result_is_null)
{
#ifdef USE_LIBXML
- xmltype *result;
+ xmltype *result;
StringInfoData buf;
- if (pg_strncasecmp(target, "xml", 3) == 0)
+ if (pg_strcasecmp(target, "xml") == 0)
ereport(ERROR,
- (errcode(ERRCODE_SYNTAX_ERROR), /* really */
+ (errcode(ERRCODE_SYNTAX_ERROR), /* really */
errmsg("invalid XML processing instruction"),
- errdetail("XML processing instruction target name cannot start with \"xml\".")));
+ errdetail("XML processing instruction target name cannot be \"%s\".", target)));
/*
- * Following the SQL standard, the null check comes after the
- * syntax check above.
+ * Following the SQL standard, the null check comes after the syntax check
+ * above.
*/
*result_is_null = arg_is_null;
if (*result_is_null)
- return NULL;
+ return NULL;
initStringInfo(&buf);
if (arg != NULL)
{
- char *string;
+ char *string;
- string = DatumGetCString(DirectFunctionCall1(textout,
- PointerGetDatum(arg)));
+ string = text_to_cstring(arg);
if (strstr(string, "?>") != NULL)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_XML_PROCESSING_INSTRUCTION),
- errmsg("invalid XML processing instruction"),
- errdetail("XML processing instruction cannot contain \"?>\".")));
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_XML_PROCESSING_INSTRUCTION),
+ errmsg("invalid XML processing instruction"),
+ errdetail("XML processing instruction cannot contain \"?>\".")));
appendStringInfoChar(&buf, ' ');
appendStringInfoString(&buf, string + strspn(string, " "));
#ifdef USE_LIBXML
char *str;
size_t len;
- xmlChar *orig_version;
+ xmlChar *orig_version;
int orig_standalone;
StringInfoData buf;
len = VARSIZE(data) - VARHDRSZ;
- str = palloc(len + 1);
- memcpy(str, VARDATA(data), len);
- str[len] = '\0';
+ str = text_to_cstring((text *) data);
parse_xml_decl((xmlChar *) str, &len, &orig_version, NULL, &orig_standalone);
/*
* Validate document (given as string) against DTD (given as external link)
- * TODO !!! use text instead of cstring for second arg
- * TODO allow passing DTD as a string value (not only as an URI)
- * TODO redesign (see comment with '!!!' below)
+ *
+ * This has been removed because it is a security hole: unprivileged users
+ * should not be able to use Postgres to fetch arbitrary external files,
+ * which unfortunately is exactly what libxml is willing to do with the DTD
+ * parameter.
*/
Datum
xmlvalidate(PG_FUNCTION_ARGS)
{
-#ifdef USE_LIBXML
- text *data = PG_GETARG_TEXT_P(0);
- text *dtdOrUri = PG_GETARG_TEXT_P(1);
- bool result = false;
- xmlParserCtxtPtr ctxt = NULL;
- xmlDocPtr doc = NULL;
- xmlDtdPtr dtd = NULL;
-
- xml_init();
-
- /* We use a PG_TRY block to ensure libxml is cleaned up on error */
- PG_TRY();
- {
- ctxt = xmlNewParserCtxt();
- if (ctxt == NULL)
- xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
- "could not allocate parser context");
-
- doc = xmlCtxtReadMemory(ctxt, (char *) VARDATA(data),
- VARSIZE(data) - VARHDRSZ,
- NULL, NULL, 0);
- if (doc == NULL)
- xml_ereport(ERROR, ERRCODE_INVALID_XML_DOCUMENT,
- "could not parse XML data");
-
-#if 0
- uri = xmlCreateURI();
- elog(NOTICE, "dtd - %s", dtdOrUri);
- dtd = palloc(sizeof(xmlDtdPtr));
- uri = xmlParseURI(dtdOrUri);
- if (uri == NULL)
- xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
- "not implemented yet... (TODO)");
- else
-#endif
- dtd = xmlParseDTD(NULL, xml_text2xmlChar(dtdOrUri));
-
- if (dtd == NULL)
- xml_ereport(ERROR, ERRCODE_INVALID_XML_DOCUMENT,
- "could not load DTD");
-
- if (xmlValidateDtd(xmlNewValidCtxt(), doc, dtd) == 1)
- result = true;
-
- if (!result)
- xml_ereport(NOTICE, ERRCODE_INVALID_XML_DOCUMENT,
- "validation against DTD failed");
-
-#if 0
- if (uri)
- xmlFreeURI(uri);
-#endif
- if (dtd)
- xmlFreeDtd(dtd);
- if (doc)
- xmlFreeDoc(doc);
- if (ctxt)
- xmlFreeParserCtxt(ctxt);
- xmlCleanupParser();
- }
- PG_CATCH();
- {
-#if 0
- if (uri)
- xmlFreeURI(uri);
-#endif
- if (dtd)
- xmlFreeDtd(dtd);
- if (doc)
- xmlFreeDoc(doc);
- if (ctxt)
- xmlFreeParserCtxt(ctxt);
- xmlCleanupParser();
-
- PG_RE_THROW();
- }
- PG_END_TRY();
-
- PG_RETURN_BOOL(result);
-#else /* not USE_LIBXML */
- NO_XML_SUPPORT();
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("xmlvalidate is not implemented")));
return 0;
-#endif /* not USE_LIBXML */
}
PG_TRY();
{
- doc = xml_parse((text *) arg, true, true, NULL);
+ doc = xml_parse((text *) arg, XMLOPTION_DOCUMENT, true, NULL);
result = true;
}
PG_CATCH();
{
- ErrorData *errdata;
+ ErrorData *errdata;
MemoryContext ecxt;
ecxt = MemoryContextSwitchTo(ccxt);
xmlFreeDoc(doc);
return result;
-#else /* not USE_LIBXML */
+#else /* not USE_LIBXML */
NO_XML_SUPPORT();
return false;
-#endif /* not USE_LIBXML */
+#endif /* not USE_LIBXML */
+}
+
+
+/*
+ * xml cleanup function for transaction end. This is also called on
+ * subtransaction abort; see notes at top of file for rationale.
+ */
+void
+AtEOXact_xml(void)
+{
+#ifdef USE_LIBXML
+ xml_memory_cleanup();
+#endif
}
#ifdef USE_LIBXML
/*
- * Container for some init stuff (not good design!)
- * TODO xmlChar is utf8-char, make proper tuning (initdb with enc!=utf8 and check)
+ * Set up for use of libxml --- this should be called by each function that
+ * is about to use libxml facilities.
+ *
+ * TODO: xmlChar is utf8-char, make proper tuning (initdb with enc!=utf8 and
+ * check)
*/
static void
xml_init(void)
{
- /*
- * Currently, we have no pure UTF-8 support for internals -- check
- * if we can work.
- */
- if (sizeof (char) != sizeof (xmlChar))
- ereport(ERROR,
- (errmsg("could not initialize XML library"),
- errdetail("libxml2 has incompatible char type: sizeof(char)=%u, sizeof(xmlChar)=%u.",
- (int) sizeof(char), (int) sizeof(xmlChar))));
+ static bool first_time = true;
- if (xml_err_buf == NULL)
+ if (first_time)
{
- /* First time through: create error buffer in permanent context */
+ /* Stuff we need do only once per session */
MemoryContext oldcontext;
+ /*
+ * Currently, we have no pure UTF-8 support for internals -- check if
+ * we can work.
+ */
+ if (sizeof(char) != sizeof(xmlChar))
+ ereport(ERROR,
+ (errmsg("could not initialize XML library"),
+ errdetail("libxml2 has incompatible char type: sizeof(char)=%u, sizeof(xmlChar)=%u.",
+ (int) sizeof(char), (int) sizeof(xmlChar))));
+
+ /* create error buffer in permanent context */
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
xml_err_buf = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
+
+ /* Now that xml_err_buf exists, safe to call xml_errorHandler */
+ xmlSetGenericErrorFunc(NULL, xml_errorHandler);
+
+ /* Set up memory allocation our way, too */
+ xml_memory_init();
+
+ /* Check library compatibility */
+ LIBXML_TEST_VERSION;
+
+ first_time = false;
}
else
{
/* Reset pre-existing buffer to empty */
- xml_err_buf->data[0] = '\0';
- xml_err_buf->len = 0;
+ Assert(xml_err_buf != NULL);
+ resetStringInfo(xml_err_buf);
+
+ /*
+ * We re-establish the callback functions every time. This makes it
+ * safe for other subsystems (PL/Perl, say) to also use libxml with
+ * their own callbacks ... so long as they likewise set up the
+ * callbacks on every use. It's cheap enough to not be worth worrying
+ * about, anyway.
+ */
+ xmlSetGenericErrorFunc(NULL, xml_errorHandler);
+ xml_memory_init();
}
- /* Now that xml_err_buf exists, safe to call xml_errorHandler */
- xmlSetGenericErrorFunc(NULL, xml_errorHandler);
-
-#ifdef NOT_USED
- /*
- * FIXME: This doesn't work because libxml assumes that whatever
- * libxml allocates, only libxml will free, so we can't just drop
- * memory contexts behind it. This needs to be refined.
- */
- xmlMemSetup(xml_pfree, xml_palloc, xml_repalloc, xml_pstrdup);
-#endif
- xmlInitParser();
- LIBXML_TEST_VERSION;
}
* to complete this.
*/
-#define CHECK_XML_SPACE(p) if (!xmlIsBlank_ch(*(p))) return XML_ERR_SPACE_REQUIRED
-#define SKIP_XML_SPACE(p) while (xmlIsBlank_ch(*(p))) (p)++
+#define CHECK_XML_SPACE(p) \
+ do { \
+ if (!xmlIsBlank_ch(*(p))) \
+ return XML_ERR_SPACE_REQUIRED; \
+ } while (0)
+
+#define SKIP_XML_SPACE(p) \
+ while (xmlIsBlank_ch(*(p))) (p)++
+
+/* Letter | Digit | '.' | '-' | '_' | ':' | CombiningChar | Extender */
+/* Beware of multiple evaluations of argument! */
+#define PG_XMLISNAMECHAR(c) \
+ (xmlIsBaseChar_ch(c) || xmlIsIdeographicQ(c) \
+ || xmlIsDigit_ch(c) \
+ || c == '.' || c == '-' || c == '_' || c == ':' \
+ || xmlIsCombiningQ(c) \
+ || xmlIsExtender_ch(c))
static int
-parse_xml_decl(const xmlChar *str, size_t *lenp, xmlChar **version, xmlChar **encoding, int *standalone)
+parse_xml_decl(const xmlChar * str, size_t *lenp,
+ xmlChar ** version, xmlChar ** encoding, int *standalone)
{
const xmlChar *p;
const xmlChar *save_p;
size_t len;
+ int utf8char;
+ int utf8len;
- p = str;
+ xml_init();
if (version)
*version = NULL;
if (standalone)
*standalone = -1;
- if (xmlStrncmp(p, (xmlChar *)"<?xml", 5) != 0)
+ p = str;
+
+ if (xmlStrncmp(p, (xmlChar *) "<?xml", 5) != 0)
+ goto finished;
+
+ /* if next char is name char, it's a PI like <?xml-stylesheet ...?> */
+ utf8len = strlen((const char *) (p + 5));
+ utf8char = xmlGetUTF8Char(p + 5, &utf8len);
+ if (PG_XMLISNAMECHAR(utf8char))
goto finished;
p += 5;
/* version */
CHECK_XML_SPACE(p);
SKIP_XML_SPACE(p);
- if (xmlStrncmp(p, (xmlChar *)"version", 7) != 0)
+ if (xmlStrncmp(p, (xmlChar *) "version", 7) != 0)
return XML_ERR_VERSION_MISSING;
p += 7;
SKIP_XML_SPACE(p);
/* encoding */
save_p = p;
SKIP_XML_SPACE(p);
- if (xmlStrncmp(p, (xmlChar *)"encoding", 8) == 0)
+ if (xmlStrncmp(p, (xmlChar *) "encoding", 8) == 0)
{
CHECK_XML_SPACE(save_p);
p += 8;
return XML_ERR_MISSING_ENCODING;
if (encoding)
- *encoding = xmlStrndup(p + 1, q - p - 1);
+ *encoding = xmlStrndup(p + 1, q - p - 1);
p = q + 1;
}
else
/* standalone */
save_p = p;
SKIP_XML_SPACE(p);
- if (xmlStrncmp(p, (xmlChar *)"standalone", 10) == 0)
+ if (xmlStrncmp(p, (xmlChar *) "standalone", 10) == 0)
{
CHECK_XML_SPACE(save_p);
p += 10;
return XML_ERR_STANDALONE_VALUE;
p += 1;
SKIP_XML_SPACE(p);
- if (xmlStrncmp(p, (xmlChar *)"'yes'", 5) == 0 || xmlStrncmp(p, (xmlChar *)"\"yes\"", 5) == 0)
+ if (xmlStrncmp(p, (xmlChar *) "'yes'", 5) == 0 ||
+ xmlStrncmp(p, (xmlChar *) "\"yes\"", 5) == 0)
{
*standalone = 1;
p += 5;
}
- else if (xmlStrncmp(p, (xmlChar *)"'no'", 4) == 0 || xmlStrncmp(p, (xmlChar *)"\"no\"", 4) == 0)
+ else if (xmlStrncmp(p, (xmlChar *) "'no'", 4) == 0 ||
+ xmlStrncmp(p, (xmlChar *) "\"no\"", 4) == 0)
{
*standalone = 0;
p += 4;
}
SKIP_XML_SPACE(p);
- if (xmlStrncmp(p, (xmlChar *)"?>", 2) != 0)
+ if (xmlStrncmp(p, (xmlChar *) "?>", 2) != 0)
return XML_ERR_XMLDECL_NOT_FINISHED;
p += 2;
/*
* Write an XML declaration. On output, we adjust the XML declaration
- * as follows. (These rules are the moral equivalent of the clause
+ * as follows. (These rules are the moral equivalent of the clause
* "Serialization of an XML value" in the SQL standard.)
*
* We try to avoid generating an XML declaration if possible. This is
* which is the default version specified in SQL:2003.
*/
static bool
-print_xml_decl(StringInfo buf, const xmlChar *version, pg_enc encoding, int standalone)
+print_xml_decl(StringInfo buf, const xmlChar * version,
+ pg_enc encoding, int standalone)
{
+ xml_init();
+
if ((version && strcmp((char *) version, PG_XML_DEFAULT_VERSION) != 0)
|| (encoding && encoding != PG_UTF8)
|| standalone != -1)
appendStringInfo(buf, " version=\"%s\"", PG_XML_DEFAULT_VERSION);
if (encoding && encoding != PG_UTF8)
- /* XXX might be useful to convert this to IANA names
- * (ISO-8859-1 instead of LATIN1 etc.); needs field
- * experience */
- appendStringInfo(buf, " encoding=\"%s\"", pg_encoding_to_char(encoding));
+ {
+ /*
+ * XXX might be useful to convert this to IANA names (ISO-8859-1
+ * instead of LATIN1 etc.); needs field experience
+ */
+ appendStringInfo(buf, " encoding=\"%s\"",
+ pg_encoding_to_char(encoding));
+ }
if (standalone == 1)
appendStringInfoString(buf, " standalone=\"yes\"");
/*
* Convert a C string to XML internal representation
*
- * TODO maybe, libxml2's xmlreader is better? (do not construct DOM, yet do not use SAX - see xml_reader.c)
+ * TODO maybe, libxml2's xmlreader is better? (do not construct DOM,
+ * yet do not use SAX - see xmlreader.c)
*/
static xmlDocPtr
-xml_parse(text *data, bool is_document, bool preserve_whitespace, xmlChar *encoding)
+xml_parse(text *data, XmlOptionType xmloption_arg, bool preserve_whitespace,
+ xmlChar * encoding)
{
- int32 len;
- xmlChar *string;
- xmlChar *utf8string;
- xmlParserCtxtPtr ctxt = NULL;
- xmlDocPtr doc = NULL;
+ int32 len;
+ xmlChar *string;
+ xmlChar *utf8string;
+ xmlParserCtxtPtr ctxt;
+ xmlDocPtr doc;
- len = VARSIZE(data) - VARHDRSZ; /* will be useful later */
+ len = VARSIZE(data) - VARHDRSZ; /* will be useful later */
string = xml_text2xmlChar(data);
utf8string = pg_do_encoding_conversion(string,
len,
- encoding
- ? pg_char_to_encoding((char *) encoding)
- : GetDatabaseEncoding(),
+ encoding ?
+ xmlChar_to_encoding(encoding) :
+ GetDatabaseEncoding(),
PG_UTF8);
xml_init();
+ xmlInitParser();
+ ctxt = xmlNewParserCtxt();
+ if (ctxt == NULL)
+ xml_ereport(ERROR, ERRCODE_OUT_OF_MEMORY,
+ "could not allocate parser context");
- /* We use a PG_TRY block to ensure libxml is cleaned up on error */
- PG_TRY();
+ if (xmloption_arg == XMLOPTION_DOCUMENT)
{
- ctxt = xmlNewParserCtxt();
- if (ctxt == NULL)
- xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
- "could not allocate parser context");
-
- if (is_document)
- {
- /*
- * Note, that here we try to apply DTD defaults
- * (XML_PARSE_DTDATTR) according to SQL/XML:10.16.7.d:
- * 'Default valies defined by internal DTD are applied'.
- * As for external DTDs, we try to support them too, (see
- * SQL/XML:10.16.7.e)
- */
- doc = xmlCtxtReadDoc(ctxt, utf8string,
- NULL,
- "UTF-8",
- XML_PARSE_NOENT | XML_PARSE_DTDATTR
- | (preserve_whitespace ? 0 : XML_PARSE_NOBLANKS));
- if (doc == NULL)
- xml_ereport(ERROR, ERRCODE_INVALID_XML_DOCUMENT,
- "invalid XML document");
- }
- else
- {
- int res_code;
- size_t count;
- xmlChar *version = NULL;
- int standalone = -1;
-
- doc = xmlNewDoc(NULL);
-
- res_code = parse_xml_decl(utf8string, &count, &version, NULL, &standalone);
- if (res_code != 0)
- xml_ereport_by_code(ERROR, ERRCODE_INVALID_XML_CONTENT,
- "invalid XML content: invalid XML declaration", res_code);
-
- res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0, utf8string + count, NULL);
- if (res_code != 0)
- xml_ereport(ERROR, ERRCODE_INVALID_XML_CONTENT,
- "invalid XML content");
-
- doc->version = xmlStrdup(version);
- doc->encoding = xmlStrdup((xmlChar *) "UTF-8");
- doc->standalone = standalone;
- }
-
- if (ctxt)
- xmlFreeParserCtxt(ctxt);
- xmlCleanupParser();
+ /*
+ * Note, that here we try to apply DTD defaults
+ * (XML_PARSE_DTDATTR) according to SQL/XML:10.16.7.d: 'Default
+ * values defined by internal DTD are applied'. As for external
+ * DTDs, we try to support them too, (see SQL/XML:10.16.7.e)
+ */
+ doc = xmlCtxtReadDoc(ctxt, utf8string,
+ NULL,
+ "UTF-8",
+ XML_PARSE_NOENT | XML_PARSE_DTDATTR
+ | (preserve_whitespace ? 0 : XML_PARSE_NOBLANKS));
+ if (doc == NULL)
+ xml_ereport(ERROR, ERRCODE_INVALID_XML_DOCUMENT,
+ "invalid XML document");
}
- PG_CATCH();
+ else
{
- if (doc)
- xmlFreeDoc(doc);
- doc = NULL;
- if (ctxt)
- xmlFreeParserCtxt(ctxt);
- xmlCleanupParser();
-
- PG_RE_THROW();
+ int res_code;
+ size_t count;
+ xmlChar *version = NULL;
+ int standalone = -1;
+
+ doc = xmlNewDoc(NULL);
+
+ res_code = parse_xml_decl(utf8string,
+ &count, &version, NULL, &standalone);
+ if (res_code != 0)
+ xml_ereport_by_code(ERROR, ERRCODE_INVALID_XML_CONTENT,
+ "invalid XML content: invalid XML declaration",
+ res_code);
+
+ res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0,
+ utf8string + count, NULL);
+ if (res_code != 0)
+ xml_ereport(ERROR, ERRCODE_INVALID_XML_CONTENT,
+ "invalid XML content");
+
+ doc->version = xmlStrdup(version);
+ doc->encoding = xmlStrdup((xmlChar *) "UTF-8");
+ doc->standalone = standalone;
}
- PG_END_TRY();
+
+ xmlFreeParserCtxt(ctxt);
return doc;
}
/*
- * xmlChar<->text convertions
+ * xmlChar<->text conversions
*/
static xmlChar *
xml_text2xmlChar(text *in)
{
- int32 len = VARSIZE(in) - VARHDRSZ;
- xmlChar *res;
+ return (xmlChar *) text_to_cstring(in);
+}
- res = palloc(len + 1);
- memcpy(res, VARDATA(in), len);
- res[len] = '\0';
- return(res);
+/*
+ * Manage the special context used for all libxml allocations
+ */
+static void
+xml_memory_init(void)
+{
+ /*
+ * Create memory context if not there already. We make it a child of
+ * TopMemoryContext, even though our current policy is that it doesn't
+ * survive past transaction end, because we want to be really really
+ * sure it doesn't go away before we've called xmlCleanupParser().
+ */
+ if (LibxmlContext == NULL)
+ LibxmlContext = AllocSetContextCreate(TopMemoryContext,
+ "LibxmlContext",
+ ALLOCSET_DEFAULT_MINSIZE,
+ ALLOCSET_DEFAULT_INITSIZE,
+ ALLOCSET_DEFAULT_MAXSIZE);
+
+ /* Re-establish the callbacks even if already set */
+ xmlMemSetup(xml_pfree, xml_palloc, xml_repalloc, xml_pstrdup);
}
+static void
+xml_memory_cleanup(void)
+{
+ if (LibxmlContext != NULL)
+ {
+ /* Give libxml a chance to clean up dangling pointers */
+ xmlCleanupParser();
+
+ /* And flush the context */
+ MemoryContextDelete(LibxmlContext);
+ LibxmlContext = NULL;
+ }
+}
-#ifdef NOT_USED
/*
* Wrappers for memory management functions
*/
static void *
xml_palloc(size_t size)
{
- return palloc(size);
+ return MemoryContextAlloc(LibxmlContext, size);
}
static char *
xml_pstrdup(const char *string)
{
- return pstrdup(string);
+ return MemoryContextStrdup(LibxmlContext, string);
}
-#endif /* NOT_USED */
/*
* any, as detail.
*/
static void
-xml_ereport(int level, int sqlcode,
- const char *msg)
+xml_ereport(int level, int sqlcode, const char *msg)
{
- char *detail;
+ char *detail;
if (xml_err_buf->len > 0)
{
detail = pstrdup(xml_err_buf->data);
- xml_err_buf->data[0] = '\0';
- xml_err_buf->len = 0;
+ resetStringInfo(xml_err_buf);
}
else
detail = NULL;
/* libxml error messages end in '\n'; get rid of it */
if (detail)
{
- size_t len;
+ size_t len;
len = strlen(detail);
- if (len > 0 && detail[len-1] == '\n')
- detail[len-1] = '\0';
+ if (len > 0 && detail[len - 1] == '\n')
+ detail[len - 1] = '\0';
ereport(level,
(errcode(sqlcode),
xml_ereport_by_code(int level, int sqlcode,
const char *msg, int code)
{
- const char *det;
+ const char *det;
- switch (code)
+ switch (code)
{
case XML_ERR_INVALID_CHAR:
- det = "Invalid character value";
+ det = gettext_noop("Invalid character value.");
break;
case XML_ERR_SPACE_REQUIRED:
- det = "Space required";
+ det = gettext_noop("Space required.");
break;
case XML_ERR_STANDALONE_VALUE:
- det = "standalone accepts only 'yes' or 'no'";
+ det = gettext_noop("standalone accepts only 'yes' or 'no'.");
break;
case XML_ERR_VERSION_MISSING:
- det = "Malformed declaration expecting version";
+ det = gettext_noop("Malformed declaration: missing version.");
break;
case XML_ERR_MISSING_ENCODING:
- det = "Missing encoding in text declaration";
+ det = gettext_noop("Missing encoding in text declaration.");
break;
case XML_ERR_XMLDECL_NOT_FINISHED:
- det = "Parsing XML declaration: '?>' expected";
+ det = gettext_noop("Parsing XML declaration: '?>' expected.");
break;
- default:
- det = "Unrecognized libxml error code: %d";
+ default:
+ det = gettext_noop("Unrecognized libxml error code: %d.");
break;
}
static pg_wchar
sqlchar_to_unicode(char *s)
{
- char *utf8string;
- pg_wchar ret[2]; /* need space for trailing zero */
+ char *utf8string;
+ pg_wchar ret[2]; /* need space for trailing zero */
utf8string = (char *) pg_do_encoding_conversion((unsigned char *) s,
pg_mblen(s),
|| xmlIsCombiningQ(c)
|| xmlIsExtenderQ(c));
}
-#endif /* USE_LIBXML */
+#endif /* USE_LIBXML */
/*
* Map SQL identifier to XML name; see SQL/XML:2003 section 9.1.
*/
char *
-map_sql_identifier_to_xml_name(char *ident, bool fully_escaped)
+map_sql_identifier_to_xml_name(char *ident, bool fully_escaped,
+ bool escape_period)
{
#ifdef USE_LIBXML
StringInfoData buf;
- char *p;
+ char *p;
+
+ /*
+ * SQL/XML doesn't make use of this case anywhere, so it's probably a
+ * mistake.
+ */
+ Assert(fully_escaped || !escape_period);
initStringInfo(&buf);
{
if (*p == ':' && (p == ident || fully_escaped))
appendStringInfo(&buf, "_x003A_");
- else if (*p == '_' && *(p+1) == 'x')
+ else if (*p == '_' && *(p + 1) == 'x')
appendStringInfo(&buf, "_x005F_");
else if (fully_escaped && p == ident &&
pg_strncasecmp(p, "xml", 3) == 0)
else
appendStringInfo(&buf, "_x0058_");
}
+ else if (escape_period && *p == '.')
+ appendStringInfo(&buf, "_x002E_");
else
{
- pg_wchar u = sqlchar_to_unicode(p);
+ pg_wchar u = sqlchar_to_unicode(p);
if ((p == ident)
? !is_valid_xml_namefirst(u)
}
return buf.data;
-#else /* not USE_LIBXML */
+#else /* not USE_LIBXML */
NO_XML_SUPPORT();
return NULL;
-#endif /* not USE_LIBXML */
+#endif /* not USE_LIBXML */
}
static char *
unicode_to_sqlchar(pg_wchar c)
{
- static unsigned char utf8string[4];
+ static unsigned char utf8string[5]; /* need trailing zero */
if (c <= 0x7F)
{
map_xml_name_to_sql_identifier(char *name)
{
StringInfoData buf;
- char *p;
+ char *p;
initStringInfo(&buf);
for (p = name; *p; p += pg_mblen(p))
{
- if (*p == '_' && *(p+1) == 'x'
- && isxdigit((unsigned char) *(p+2))
- && isxdigit((unsigned char) *(p+3))
- && isxdigit((unsigned char) *(p+4))
- && isxdigit((unsigned char) *(p+5))
- && *(p+6) == '_')
+ if (*p == '_' && *(p + 1) == 'x'
+ && isxdigit((unsigned char) *(p + 2))
+ && isxdigit((unsigned char) *(p + 3))
+ && isxdigit((unsigned char) *(p + 4))
+ && isxdigit((unsigned char) *(p + 5))
+ && *(p + 6) == '_')
{
unsigned int u;
return buf.data;
}
-
/*
* Map SQL value to XML value; see SQL/XML:2003 section 9.16.
*/
initStringInfo(&buf);
- if (is_array_type(type))
+ if (type_is_array(type))
{
- int i;
- ArrayType *array;
- Oid elmtype;
- int16 elmlen;
- bool elmbyval;
- char elmalign;
+ ArrayType *array;
+ Oid elmtype;
+ int16 elmlen;
+ bool elmbyval;
+ char elmalign;
+ int num_elems;
+ Datum *elem_values;
+ bool *elem_nulls;
+ int i;
array = DatumGetArrayTypeP(value);
-
- /* TODO: need some code-fu here to remove this limitation */
- if (ARR_NDIM(array) != 1)
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("only supported for one-dimensional array")));
-
elmtype = ARR_ELEMTYPE(array);
get_typlenbyvalalign(elmtype, &elmlen, &elmbyval, &elmalign);
- for (i = ARR_LBOUND(array)[0];
- i < ARR_LBOUND(array)[0] + ARR_DIMS(array)[0];
- i++)
- {
- Datum subval;
- bool isnull;
+ deconstruct_array(array, elmtype,
+ elmlen, elmbyval, elmalign,
+ &elem_values, &elem_nulls,
+ &num_elems);
- subval = array_ref(array, 1, &i, -1, elmlen, elmbyval, elmalign, &isnull);
+ for (i = 0; i < num_elems; i++)
+ {
+ if (elem_nulls[i])
+ continue;
appendStringInfoString(&buf, "<element>");
- appendStringInfoString(&buf, map_sql_value_to_xml_value(subval, elmtype));
+ appendStringInfoString(&buf,
+ map_sql_value_to_xml_value(elem_values[i],
+ elmtype));
appendStringInfoString(&buf, "</element>");
}
+
+ pfree(elem_values);
+ pfree(elem_nulls);
}
else
{
- Oid typeOut;
- bool isvarlena;
- char *p, *str;
+ Oid typeOut;
+ bool isvarlena;
+ char *p,
+ *str;
+
+ /*
+ * Special XSD formatting for some data types
+ */
+ switch (type)
+ {
+ case BOOLOID:
+ if (DatumGetBool(value))
+ return "true";
+ else
+ return "false";
+
+ case DATEOID:
+ {
+ DateADT date;
+ struct pg_tm tm;
+ char buf[MAXDATELEN + 1];
+
+ date = DatumGetDateADT(value);
+ j2date(date + POSTGRES_EPOCH_JDATE,
+ &(tm.tm_year), &(tm.tm_mon), &(tm.tm_mday));
+ EncodeDateOnly(&tm, USE_XSD_DATES, buf);
+
+ return pstrdup(buf);
+ }
+
+ case TIMESTAMPOID:
+ {
+ Timestamp timestamp;
+ struct pg_tm tm;
+ fsec_t fsec;
+ char *tzn = NULL;
+ char buf[MAXDATELEN + 1];
+
+ timestamp = DatumGetTimestamp(value);
+
+ /* XSD doesn't support infinite values */
+ if (TIMESTAMP_NOT_FINITE(timestamp))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
+ errmsg("timestamp out of range")));
+ else if (timestamp2tm(timestamp, NULL, &tm, &fsec, NULL, NULL) == 0)
+ EncodeDateTime(&tm, fsec, NULL, &tzn, USE_XSD_DATES, buf);
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
+ errmsg("timestamp out of range")));
+
+ return pstrdup(buf);
+ }
+
+ case TIMESTAMPTZOID:
+ {
+ TimestampTz timestamp;
+ struct pg_tm tm;
+ int tz;
+ fsec_t fsec;
+ char *tzn = NULL;
+ char buf[MAXDATELEN + 1];
+
+ timestamp = DatumGetTimestamp(value);
+
+ /* XSD doesn't support infinite values */
+ if (TIMESTAMP_NOT_FINITE(timestamp))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
+ errmsg("timestamp out of range")));
+ else if (timestamp2tm(timestamp, &tz, &tm, &fsec, &tzn, NULL) == 0)
+ EncodeDateTime(&tm, fsec, &tz, &tzn, USE_XSD_DATES, buf);
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
+ errmsg("timestamp out of range")));
+
+ return pstrdup(buf);
+ }
+ }
getTypeOutputInfo(type, &typeOut, &isvarlena);
str = OidOutputFunctionCall(typeOut, value);
{
xmlBufferPtr buf;
xmlTextWriterPtr writer;
- char *result;
+ char *result;
+
+ xml_init();
buf = xmlBufferCreate();
writer = xmlNewTextWriterMemory(buf, 0);
xmlBufferFree(buf);
return result;
}
-#endif /* USE_LIBXML */
+#endif /* USE_LIBXML */
for (p = str; *p; p += pg_mblen(p))
{
return buf.data;
}
+
+
+static char *
+_SPI_strdup(const char *s)
+{
+ size_t len = strlen(s) + 1;
+ char *ret = SPI_palloc(len);
+
+ memcpy(ret, s, len);
+ return ret;
+}
+
+
+/*
+ * SQL to XML mapping functions
+ *
+ * What follows below is intentionally organized so that you can read
+ * along in the SQL/XML:2003 standard. The functions are mostly split
+ * up and ordered they way the clauses lay out in the standards
+ * document, and the identifiers are also aligned with the standard
+ * text. (SQL/XML:2006 appears to be ordered differently,
+ * unfortunately.)
+ *
+ * There are many things going on there:
+ *
+ * There are two kinds of mappings: Mapping SQL data (table contents)
+ * to XML documents, and mapping SQL structure (the "schema") to XML
+ * Schema. And there are functions that do both at the same time.
+ *
+ * Then you can map a database, a schema, or a table, each in both
+ * ways. This breaks down recursively: Mapping a database invokes
+ * mapping schemas, which invokes mapping tables, which invokes
+ * mapping rows, which invokes mapping columns, although you can't
+ * call the last two from the outside. Because of this, there are a
+ * number of xyz_internal() functions which are to be called both from
+ * the function manager wrapper and from some upper layer in a
+ * recursive call.
+ *
+ * See the documentation about what the common function arguments
+ * nulls, tableforest, and targetns mean.
+ *
+ * Some style guidelines for XML output: Use double quotes for quoting
+ * XML attributes. Indent XML elements by two spaces, but remember
+ * that a lot of code is called recursively at different levels, so
+ * it's better not to indent rather than create output that indents
+ * and outdents weirdly. Add newlines to make the output look nice.
+ */
+
+
+/*
+ * Visibility of objects for XML mappings; see SQL/XML:2003 section
+ * 4.8.5.
+ */
+
+/*
+ * Given a query, which must return type oid as first column, produce
+ * a list of Oids with the query results.
+ */
+static List *
+query_to_oid_list(const char *query)
+{
+ int i;
+ List *list = NIL;
+
+ SPI_execute(query, true, 0);
+
+ for (i = 0; i < SPI_processed; i++)
+ {
+ Datum oid;
+ bool isnull;
+
+ oid = SPI_getbinval(SPI_tuptable->vals[i],
+ SPI_tuptable->tupdesc,
+ 1,
+ &isnull);
+ if (!isnull)
+ list = lappend_oid(list, DatumGetObjectId(oid));
+ }
+
+ return list;
+}
+
+
+static List *
+schema_get_xml_visible_tables(Oid nspid)
+{
+ StringInfoData query;
+
+ initStringInfo(&query);
+ appendStringInfo(&query, "SELECT oid FROM pg_catalog.pg_class WHERE relnamespace = %u AND relkind IN ('r', 'v') AND pg_catalog.has_table_privilege (oid, 'SELECT') ORDER BY relname;", nspid);
+
+ return query_to_oid_list(query.data);
+}
+
+
+/*
+ * Including the system schemas is probably not useful for a database
+ * mapping.
+ */
+#define XML_VISIBLE_SCHEMAS_EXCLUDE "(nspname ~ '^pg_' OR nspname = 'information_schema')"
+
+#define XML_VISIBLE_SCHEMAS "SELECT oid FROM pg_catalog.pg_namespace WHERE pg_catalog.has_schema_privilege (oid, 'USAGE') AND NOT " XML_VISIBLE_SCHEMAS_EXCLUDE
+
+
+static List *
+database_get_xml_visible_schemas(void)
+{
+ return query_to_oid_list(XML_VISIBLE_SCHEMAS " ORDER BY nspname;");
+}
+
+
+static List *
+database_get_xml_visible_tables(void)
+{
+ /* At the moment there is no order required here. */
+ return query_to_oid_list("SELECT oid FROM pg_catalog.pg_class WHERE relkind IN ('r', 'v') AND pg_catalog.has_table_privilege (pg_class.oid, 'SELECT') AND relnamespace IN (" XML_VISIBLE_SCHEMAS ");");
+}
+
+
+/*
+ * Map SQL table to XML and/or XML Schema document; see SQL/XML:2003
+ * section 9.3.
+ */
+
+static StringInfo
+table_to_xml_internal(Oid relid,
+ const char *xmlschema, bool nulls, bool tableforest,
+ const char *targetns, bool top_level)
+{
+ StringInfoData query;
+
+ initStringInfo(&query);
+ appendStringInfo(&query, "SELECT * FROM %s",
+ DatumGetCString(DirectFunctionCall1(regclassout,
+ ObjectIdGetDatum(relid))));
+ return query_to_xml_internal(query.data, get_rel_name(relid),
+ xmlschema, nulls, tableforest,
+ targetns, top_level);
+}
+
+
+Datum
+table_to_xml(PG_FUNCTION_ARGS)
+{
+ Oid relid = PG_GETARG_OID(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(table_to_xml_internal(relid, NULL,
+ nulls, tableforest,
+ targetns, true)));
+}
+
+
+Datum
+query_to_xml(PG_FUNCTION_ARGS)
+{
+ char *query = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(query_to_xml_internal(query, NULL,
+ NULL, nulls, tableforest,
+ targetns, true)));
+}
+
+
+Datum
+cursor_to_xml(PG_FUNCTION_ARGS)
+{
+ char *name = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ int32 count = PG_GETARG_INT32(1);
+ bool nulls = PG_GETARG_BOOL(2);
+ bool tableforest = PG_GETARG_BOOL(3);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(4));
+
+ StringInfoData result;
+ Portal portal;
+ int i;
+
+ initStringInfo(&result);
+
+ SPI_connect();
+ portal = SPI_cursor_find(name);
+ if (portal == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_CURSOR),
+ errmsg("cursor \"%s\" does not exist", name)));
+
+ SPI_cursor_fetch(portal, true, count);
+ for (i = 0; i < SPI_processed; i++)
+ SPI_sql_row_to_xmlelement(i, &result, NULL, nulls,
+ tableforest, targetns, true);
+
+ SPI_finish();
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(&result));
+}
+
+
+/*
+ * Write the start tag of the root element of a data mapping.
+ *
+ * top_level means that this is the very top level of the eventual
+ * output. For example, when the user calls table_to_xml, then a call
+ * with a table name to this function is the top level. When the user
+ * calls database_to_xml, then a call with a schema name to this
+ * function is not the top level. If top_level is false, then the XML
+ * namespace declarations are omitted, because they supposedly already
+ * appeared earlier in the output. Repeating them is not wrong, but
+ * it looks ugly.
+ */
+static void
+xmldata_root_element_start(StringInfo result, const char *eltname,
+ const char *xmlschema, const char *targetns,
+ bool top_level)
+{
+ /* This isn't really wrong but currently makes no sense. */
+ Assert(top_level || !xmlschema);
+
+ appendStringInfo(result, "<%s", eltname);
+ if (top_level)
+ {
+ appendStringInfoString(result, " xmlns:xsi=\"" NAMESPACE_XSI "\"");
+ if (strlen(targetns) > 0)
+ appendStringInfo(result, " xmlns=\"%s\"", targetns);
+ }
+ if (xmlschema)
+ {
+ /* FIXME: better targets */
+ if (strlen(targetns) > 0)
+ appendStringInfo(result, " xsi:schemaLocation=\"%s #\"", targetns);
+ else
+ appendStringInfo(result, " xsi:noNamespaceSchemaLocation=\"#\"");
+ }
+ appendStringInfo(result, ">\n\n");
+}
+
+
+static void
+xmldata_root_element_end(StringInfo result, const char *eltname)
+{
+ appendStringInfo(result, "</%s>\n", eltname);
+}
+
+
+static StringInfo
+query_to_xml_internal(const char *query, char *tablename,
+ const char *xmlschema, bool nulls, bool tableforest,
+ const char *targetns, bool top_level)
+{
+ StringInfo result;
+ char *xmltn;
+ int i;
+
+ if (tablename)
+ xmltn = map_sql_identifier_to_xml_name(tablename, true, false);
+ else
+ xmltn = "table";
+
+ result = makeStringInfo();
+
+ SPI_connect();
+ if (SPI_execute(query, true, 0) != SPI_OK_SELECT)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_EXCEPTION),
+ errmsg("invalid query")));
+
+ if (!tableforest)
+ xmldata_root_element_start(result, xmltn, xmlschema,
+ targetns, top_level);
+
+ if (xmlschema)
+ appendStringInfo(result, "%s\n\n", xmlschema);
+
+ for (i = 0; i < SPI_processed; i++)
+ SPI_sql_row_to_xmlelement(i, result, tablename, nulls,
+ tableforest, targetns, top_level);
+
+ if (!tableforest)
+ xmldata_root_element_end(result, xmltn);
+
+ SPI_finish();
+
+ return result;
+}
+
+
+Datum
+table_to_xmlschema(PG_FUNCTION_ARGS)
+{
+ Oid relid = PG_GETARG_OID(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+ const char *result;
+ Relation rel;
+
+ rel = heap_open(relid, AccessShareLock);
+ result = map_sql_table_to_xmlschema(rel->rd_att, relid, nulls,
+ tableforest, targetns);
+ heap_close(rel, NoLock);
+
+ PG_RETURN_XML_P(cstring_to_xmltype(result));
+}
+
+
+Datum
+query_to_xmlschema(PG_FUNCTION_ARGS)
+{
+ char *query = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+ const char *result;
+ SPIPlanPtr plan;
+ Portal portal;
+
+ SPI_connect();
+
+ if ((plan = SPI_prepare(query, 0, NULL)) == NULL)
+ elog(ERROR, "SPI_prepare(\"%s\") failed", query);
+
+ if ((portal = SPI_cursor_open(NULL, plan, NULL, NULL, true)) == NULL)
+ elog(ERROR, "SPI_cursor_open(\"%s\") failed", query);
+
+ result = _SPI_strdup(map_sql_table_to_xmlschema(portal->tupDesc,
+ InvalidOid, nulls,
+ tableforest, targetns));
+ SPI_cursor_close(portal);
+ SPI_finish();
+
+ PG_RETURN_XML_P(cstring_to_xmltype(result));
+}
+
+
+Datum
+cursor_to_xmlschema(PG_FUNCTION_ARGS)
+{
+ char *name = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+ const char *xmlschema;
+ Portal portal;
+
+ SPI_connect();
+ portal = SPI_cursor_find(name);
+ if (portal == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_CURSOR),
+ errmsg("cursor \"%s\" does not exist", name)));
+
+ xmlschema = _SPI_strdup(map_sql_table_to_xmlschema(portal->tupDesc,
+ InvalidOid, nulls,
+ tableforest, targetns));
+ SPI_finish();
+
+ PG_RETURN_XML_P(cstring_to_xmltype(xmlschema));
+}
+
+
+Datum
+table_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
+{
+ Oid relid = PG_GETARG_OID(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+ Relation rel;
+ const char *xmlschema;
+
+ rel = heap_open(relid, AccessShareLock);
+ xmlschema = map_sql_table_to_xmlschema(rel->rd_att, relid, nulls,
+ tableforest, targetns);
+ heap_close(rel, NoLock);
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(table_to_xml_internal(relid,
+ xmlschema, nulls, tableforest,
+ targetns, true)));
+}
+
+
+Datum
+query_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
+{
+ char *query = text_to_cstring(PG_GETARG_TEXT_PP(0));
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+
+ const char *xmlschema;
+ SPIPlanPtr plan;
+ Portal portal;
+
+ SPI_connect();
+
+ if ((plan = SPI_prepare(query, 0, NULL)) == NULL)
+ elog(ERROR, "SPI_prepare(\"%s\") failed", query);
+
+ if ((portal = SPI_cursor_open(NULL, plan, NULL, NULL, true)) == NULL)
+ elog(ERROR, "SPI_cursor_open(\"%s\") failed", query);
+
+ xmlschema = _SPI_strdup(map_sql_table_to_xmlschema(portal->tupDesc,
+ InvalidOid, nulls, tableforest, targetns));
+ SPI_cursor_close(portal);
+ SPI_finish();
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(query_to_xml_internal(query, NULL,
+ xmlschema, nulls, tableforest,
+ targetns, true)));
+}
+
+
+/*
+ * Map SQL schema to XML and/or XML Schema document; see SQL/XML:2003
+ * section 9.4.
+ */
+
+static StringInfo
+schema_to_xml_internal(Oid nspid, const char *xmlschema, bool nulls,
+ bool tableforest, const char *targetns, bool top_level)
+{
+ StringInfo result;
+ char *xmlsn;
+ List *relid_list;
+ ListCell *cell;
+
+ xmlsn = map_sql_identifier_to_xml_name(get_namespace_name(nspid),
+ true, false);
+ result = makeStringInfo();
+
+ xmldata_root_element_start(result, xmlsn, xmlschema, targetns, top_level);
+
+ if (xmlschema)
+ appendStringInfo(result, "%s\n\n", xmlschema);
+
+ SPI_connect();
+
+ relid_list = schema_get_xml_visible_tables(nspid);
+
+ SPI_push();
+
+ foreach(cell, relid_list)
+ {
+ Oid relid = lfirst_oid(cell);
+ StringInfo subres;
+
+ subres = table_to_xml_internal(relid, NULL, nulls, tableforest,
+ targetns, false);
+
+ appendStringInfoString(result, subres->data);
+ appendStringInfoChar(result, '\n');
+ }
+
+ SPI_pop();
+ SPI_finish();
+
+ xmldata_root_element_end(result, xmlsn);
+
+ return result;
+}
+
+
+Datum
+schema_to_xml(PG_FUNCTION_ARGS)
+{
+ Name name = PG_GETARG_NAME(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+
+ char *schemaname;
+ Oid nspid;
+
+ schemaname = NameStr(*name);
+ nspid = LookupExplicitNamespace(schemaname);
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(schema_to_xml_internal(nspid, NULL,
+ nulls, tableforest, targetns, true)));
+}
+
+
+/*
+ * Write the start element of the root element of an XML Schema mapping.
+ */
+static void
+xsd_schema_element_start(StringInfo result, const char *targetns)
+{
+ appendStringInfoString(result,
+ "<xsd:schema\n"
+ " xmlns:xsd=\"" NAMESPACE_XSD "\"");
+ if (strlen(targetns) > 0)
+ appendStringInfo(result,
+ "\n"
+ " targetNamespace=\"%s\"\n"
+ " elementFormDefault=\"qualified\"",
+ targetns);
+ appendStringInfoString(result,
+ ">\n\n");
+}
+
+
+static void
+xsd_schema_element_end(StringInfo result)
+{
+ appendStringInfoString(result, "</xsd:schema>");
+}
+
+
+static StringInfo
+schema_to_xmlschema_internal(const char *schemaname, bool nulls,
+ bool tableforest, const char *targetns)
+{
+ Oid nspid;
+ List *relid_list;
+ List *tupdesc_list;
+ ListCell *cell;
+ StringInfo result;
+
+ result = makeStringInfo();
+
+ nspid = LookupExplicitNamespace(schemaname);
+
+ xsd_schema_element_start(result, targetns);
+
+ SPI_connect();
+
+ relid_list = schema_get_xml_visible_tables(nspid);
+
+ tupdesc_list = NIL;
+ foreach(cell, relid_list)
+ {
+ Relation rel;
+
+ rel = heap_open(lfirst_oid(cell), AccessShareLock);
+ tupdesc_list = lappend(tupdesc_list, CreateTupleDescCopy(rel->rd_att));
+ heap_close(rel, NoLock);
+ }
+
+ appendStringInfoString(result,
+ map_sql_typecoll_to_xmlschema_types(tupdesc_list));
+
+ appendStringInfoString(result,
+ map_sql_schema_to_xmlschema_types(nspid, relid_list,
+ nulls, tableforest, targetns));
+
+ xsd_schema_element_end(result);
+
+ SPI_finish();
+
+ return result;
+}
+
+
+Datum
+schema_to_xmlschema(PG_FUNCTION_ARGS)
+{
+ Name name = PG_GETARG_NAME(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(schema_to_xmlschema_internal(NameStr(*name),
+ nulls, tableforest, targetns)));
+}
+
+
+Datum
+schema_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
+{
+ Name name = PG_GETARG_NAME(0);
+ bool nulls = PG_GETARG_BOOL(1);
+ bool tableforest = PG_GETARG_BOOL(2);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
+ char *schemaname;
+ Oid nspid;
+ StringInfo xmlschema;
+
+ schemaname = NameStr(*name);
+ nspid = LookupExplicitNamespace(schemaname);
+
+ xmlschema = schema_to_xmlschema_internal(schemaname, nulls,
+ tableforest, targetns);
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(schema_to_xml_internal(nspid,
+ xmlschema->data, nulls,
+ tableforest, targetns, true)));
+}
+
+
+/*
+ * Map SQL database to XML and/or XML Schema document; see SQL/XML:2003
+ * section 9.5.
+ */
+
+static StringInfo
+database_to_xml_internal(const char *xmlschema, bool nulls,
+ bool tableforest, const char *targetns)
+{
+ StringInfo result;
+ List *nspid_list;
+ ListCell *cell;
+ char *xmlcn;
+
+ xmlcn = map_sql_identifier_to_xml_name(get_database_name(MyDatabaseId),
+ true, false);
+ result = makeStringInfo();
+
+ xmldata_root_element_start(result, xmlcn, xmlschema, targetns, true);
+
+ if (xmlschema)
+ appendStringInfo(result, "%s\n\n", xmlschema);
+
+ SPI_connect();
+
+ nspid_list = database_get_xml_visible_schemas();
+
+ SPI_push();
+
+ foreach(cell, nspid_list)
+ {
+ Oid nspid = lfirst_oid(cell);
+ StringInfo subres;
+
+ subres = schema_to_xml_internal(nspid, NULL, nulls,
+ tableforest, targetns, false);
+
+ appendStringInfoString(result, subres->data);
+ appendStringInfoChar(result, '\n');
+ }
+
+ SPI_pop();
+ SPI_finish();
+
+ xmldata_root_element_end(result, xmlcn);
+
+ return result;
+}
+
+
+Datum
+database_to_xml(PG_FUNCTION_ARGS)
+{
+ bool nulls = PG_GETARG_BOOL(0);
+ bool tableforest = PG_GETARG_BOOL(1);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(2));
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(database_to_xml_internal(NULL, nulls,
+ tableforest, targetns)));
+}
+
+
+static StringInfo
+database_to_xmlschema_internal(bool nulls, bool tableforest,
+ const char *targetns)
+{
+ List *relid_list;
+ List *nspid_list;
+ List *tupdesc_list;
+ ListCell *cell;
+ StringInfo result;
+
+ result = makeStringInfo();
+
+ xsd_schema_element_start(result, targetns);
+
+ SPI_connect();
+
+ relid_list = database_get_xml_visible_tables();
+ nspid_list = database_get_xml_visible_schemas();
+
+ tupdesc_list = NIL;
+ foreach(cell, relid_list)
+ {
+ Relation rel;
+
+ rel = heap_open(lfirst_oid(cell), AccessShareLock);
+ tupdesc_list = lappend(tupdesc_list, CreateTupleDescCopy(rel->rd_att));
+ heap_close(rel, NoLock);
+ }
+
+ appendStringInfoString(result,
+ map_sql_typecoll_to_xmlschema_types(tupdesc_list));
+
+ appendStringInfoString(result,
+ map_sql_catalog_to_xmlschema_types(nspid_list, nulls, tableforest, targetns));
+
+ xsd_schema_element_end(result);
+
+ SPI_finish();
+
+ return result;
+}
+
+
+Datum
+database_to_xmlschema(PG_FUNCTION_ARGS)
+{
+ bool nulls = PG_GETARG_BOOL(0);
+ bool tableforest = PG_GETARG_BOOL(1);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(2));
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(database_to_xmlschema_internal(nulls,
+ tableforest, targetns)));
+}
+
+
+Datum
+database_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
+{
+ bool nulls = PG_GETARG_BOOL(0);
+ bool tableforest = PG_GETARG_BOOL(1);
+ const char *targetns = text_to_cstring(PG_GETARG_TEXT_PP(2));
+ StringInfo xmlschema;
+
+ xmlschema = database_to_xmlschema_internal(nulls, tableforest, targetns);
+
+ PG_RETURN_XML_P(stringinfo_to_xmltype(database_to_xml_internal(xmlschema->data,
+ nulls, tableforest, targetns)));
+}
+
+
+/*
+ * Map a multi-part SQL name to an XML name; see SQL/XML:2003 section
+ * 9.2.
+ */
+static char *
+map_multipart_sql_identifier_to_xml_name(char *a, char *b, char *c, char *d)
+{
+ StringInfoData result;
+
+ initStringInfo(&result);
+
+ if (a)
+ appendStringInfo(&result, "%s",
+ map_sql_identifier_to_xml_name(a, true, true));
+ if (b)
+ appendStringInfo(&result, ".%s",
+ map_sql_identifier_to_xml_name(b, true, true));
+ if (c)
+ appendStringInfo(&result, ".%s",
+ map_sql_identifier_to_xml_name(c, true, true));
+ if (d)
+ appendStringInfo(&result, ".%s",
+ map_sql_identifier_to_xml_name(d, true, true));
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL table to an XML Schema document; see SQL/XML:2003
+ * section 9.3.
+ *
+ * Map an SQL table to XML Schema data types; see SQL/XML:2003 section
+ * 9.6.
+ */
+static const char *
+map_sql_table_to_xmlschema(TupleDesc tupdesc, Oid relid, bool nulls,
+ bool tableforest, const char *targetns)
+{
+ int i;
+ char *xmltn;
+ char *tabletypename;
+ char *rowtypename;
+ StringInfoData result;
+
+ initStringInfo(&result);
+
+ if (OidIsValid(relid))
+ {
+ HeapTuple tuple;
+ Form_pg_class reltuple;
+
+ tuple = SearchSysCache(RELOID,
+ ObjectIdGetDatum(relid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(tuple))
+ elog(ERROR, "cache lookup failed for relation %u", relid);
+ reltuple = (Form_pg_class) GETSTRUCT(tuple);
+
+ xmltn = map_sql_identifier_to_xml_name(NameStr(reltuple->relname),
+ true, false);
+
+ tabletypename = map_multipart_sql_identifier_to_xml_name("TableType",
+ get_database_name(MyDatabaseId),
+ get_namespace_name(reltuple->relnamespace),
+ NameStr(reltuple->relname));
+
+ rowtypename = map_multipart_sql_identifier_to_xml_name("RowType",
+ get_database_name(MyDatabaseId),
+ get_namespace_name(reltuple->relnamespace),
+ NameStr(reltuple->relname));
+
+ ReleaseSysCache(tuple);
+ }
+ else
+ {
+ if (tableforest)
+ xmltn = "row";
+ else
+ xmltn = "table";
+
+ tabletypename = "TableType";
+ rowtypename = "RowType";
+ }
+
+ xsd_schema_element_start(&result, targetns);
+
+ appendStringInfoString(&result,
+ map_sql_typecoll_to_xmlschema_types(list_make1(tupdesc)));
+
+ appendStringInfo(&result,
+ "<xsd:complexType name=\"%s\">\n"
+ " <xsd:sequence>\n",
+ rowtypename);
+
+ for (i = 0; i < tupdesc->natts; i++)
+ appendStringInfo(&result,
+ " <xsd:element name=\"%s\" type=\"%s\"%s></xsd:element>\n",
+ map_sql_identifier_to_xml_name(NameStr(tupdesc->attrs[i]->attname),
+ true, false),
+ map_sql_type_to_xml_name(tupdesc->attrs[i]->atttypid, -1),
+ nulls ? " nillable=\"true\"" : " minOccurs=\"0\"");
+
+ appendStringInfoString(&result,
+ " </xsd:sequence>\n"
+ "</xsd:complexType>\n\n");
+
+ if (!tableforest)
+ {
+ appendStringInfo(&result,
+ "<xsd:complexType name=\"%s\">\n"
+ " <xsd:sequence>\n"
+ " <xsd:element name=\"row\" type=\"%s\" minOccurs=\"0\" maxOccurs=\"unbounded\"/>\n"
+ " </xsd:sequence>\n"
+ "</xsd:complexType>\n\n",
+ tabletypename, rowtypename);
+
+ appendStringInfo(&result,
+ "<xsd:element name=\"%s\" type=\"%s\"/>\n\n",
+ xmltn, tabletypename);
+ }
+ else
+ appendStringInfo(&result,
+ "<xsd:element name=\"%s\" type=\"%s\"/>\n\n",
+ xmltn, rowtypename);
+
+ xsd_schema_element_end(&result);
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL schema to XML Schema data types; see SQL/XML section
+ * 9.7.
+ */
+static const char *
+map_sql_schema_to_xmlschema_types(Oid nspid, List *relid_list, bool nulls,
+ bool tableforest, const char *targetns)
+{
+ char *dbname;
+ char *nspname;
+ char *xmlsn;
+ char *schematypename;
+ StringInfoData result;
+ ListCell *cell;
+
+ dbname = get_database_name(MyDatabaseId);
+ nspname = get_namespace_name(nspid);
+
+ initStringInfo(&result);
+
+ xmlsn = map_sql_identifier_to_xml_name(nspname, true, false);
+
+ schematypename = map_multipart_sql_identifier_to_xml_name("SchemaType",
+ dbname,
+ nspname,
+ NULL);
+
+ appendStringInfo(&result,
+ "<xsd:complexType name=\"%s\">\n", schematypename);
+ if (!tableforest)
+ appendStringInfoString(&result,
+ " <xsd:all>\n");
+ else
+ appendStringInfoString(&result,
+ " <xsd:sequence>\n");
+
+ foreach(cell, relid_list)
+ {
+ Oid relid = lfirst_oid(cell);
+ char *relname = get_rel_name(relid);
+ char *xmltn = map_sql_identifier_to_xml_name(relname, true, false);
+ char *tabletypename = map_multipart_sql_identifier_to_xml_name(tableforest ? "RowType" : "TableType",
+ dbname,
+ nspname,
+ relname);
+
+ if (!tableforest)
+ appendStringInfo(&result,
+ " <xsd:element name=\"%s\" type=\"%s\"/>\n",
+ xmltn, tabletypename);
+ else
+ appendStringInfo(&result,
+ " <xsd:element name=\"%s\" type=\"%s\" minOccurs=\"0\" maxOccurs=\"unbounded\"/>\n",
+ xmltn, tabletypename);
+ }
+
+ if (!tableforest)
+ appendStringInfoString(&result,
+ " </xsd:all>\n");
+ else
+ appendStringInfoString(&result,
+ " </xsd:sequence>\n");
+ appendStringInfoString(&result,
+ "</xsd:complexType>\n\n");
+
+ appendStringInfo(&result,
+ "<xsd:element name=\"%s\" type=\"%s\"/>\n\n",
+ xmlsn, schematypename);
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL catalog to XML Schema data types; see SQL/XML section
+ * 9.8.
+ */
+static const char *
+map_sql_catalog_to_xmlschema_types(List *nspid_list, bool nulls,
+ bool tableforest, const char *targetns)
+{
+ char *dbname;
+ char *xmlcn;
+ char *catalogtypename;
+ StringInfoData result;
+ ListCell *cell;
+
+ dbname = get_database_name(MyDatabaseId);
+
+ initStringInfo(&result);
+
+ xmlcn = map_sql_identifier_to_xml_name(dbname, true, false);
+
+ catalogtypename = map_multipart_sql_identifier_to_xml_name("CatalogType",
+ dbname,
+ NULL,
+ NULL);
+
+ appendStringInfo(&result,
+ "<xsd:complexType name=\"%s\">\n", catalogtypename);
+ appendStringInfoString(&result,
+ " <xsd:all>\n");
+
+ foreach(cell, nspid_list)
+ {
+ Oid nspid = lfirst_oid(cell);
+ char *nspname = get_namespace_name(nspid);
+ char *xmlsn = map_sql_identifier_to_xml_name(nspname, true, false);
+ char *schematypename = map_multipart_sql_identifier_to_xml_name("SchemaType",
+ dbname,
+ nspname,
+ NULL);
+
+ appendStringInfo(&result,
+ " <xsd:element name=\"%s\" type=\"%s\"/>\n",
+ xmlsn, schematypename);
+ }
+
+ appendStringInfoString(&result,
+ " </xsd:all>\n");
+ appendStringInfoString(&result,
+ "</xsd:complexType>\n\n");
+
+ appendStringInfo(&result,
+ "<xsd:element name=\"%s\" type=\"%s\"/>\n\n",
+ xmlcn, catalogtypename);
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL data type to an XML name; see SQL/XML:2003 section 9.9.
+ */
+static const char *
+map_sql_type_to_xml_name(Oid typeoid, int typmod)
+{
+ StringInfoData result;
+
+ initStringInfo(&result);
+
+ switch (typeoid)
+ {
+ case BPCHAROID:
+ if (typmod == -1)
+ appendStringInfo(&result, "CHAR");
+ else
+ appendStringInfo(&result, "CHAR_%d", typmod - VARHDRSZ);
+ break;
+ case VARCHAROID:
+ if (typmod == -1)
+ appendStringInfo(&result, "VARCHAR");
+ else
+ appendStringInfo(&result, "VARCHAR_%d", typmod - VARHDRSZ);
+ break;
+ case NUMERICOID:
+ if (typmod == -1)
+ appendStringInfo(&result, "NUMERIC");
+ else
+ appendStringInfo(&result, "NUMERIC_%d_%d",
+ ((typmod - VARHDRSZ) >> 16) & 0xffff,
+ (typmod - VARHDRSZ) & 0xffff);
+ break;
+ case INT4OID:
+ appendStringInfo(&result, "INTEGER");
+ break;
+ case INT2OID:
+ appendStringInfo(&result, "SMALLINT");
+ break;
+ case INT8OID:
+ appendStringInfo(&result, "BIGINT");
+ break;
+ case FLOAT4OID:
+ appendStringInfo(&result, "REAL");
+ break;
+ case FLOAT8OID:
+ appendStringInfo(&result, "DOUBLE");
+ break;
+ case BOOLOID:
+ appendStringInfo(&result, "BOOLEAN");
+ break;
+ case TIMEOID:
+ if (typmod == -1)
+ appendStringInfo(&result, "TIME");
+ else
+ appendStringInfo(&result, "TIME_%d", typmod);
+ break;
+ case TIMETZOID:
+ if (typmod == -1)
+ appendStringInfo(&result, "TIME_WTZ");
+ else
+ appendStringInfo(&result, "TIME_WTZ_%d", typmod);
+ break;
+ case TIMESTAMPOID:
+ if (typmod == -1)
+ appendStringInfo(&result, "TIMESTAMP");
+ else
+ appendStringInfo(&result, "TIMESTAMP_%d", typmod);
+ break;
+ case TIMESTAMPTZOID:
+ if (typmod == -1)
+ appendStringInfo(&result, "TIMESTAMP_WTZ");
+ else
+ appendStringInfo(&result, "TIMESTAMP_WTZ_%d", typmod);
+ break;
+ case DATEOID:
+ appendStringInfo(&result, "DATE");
+ break;
+ case XMLOID:
+ appendStringInfo(&result, "XML");
+ break;
+ default:
+ {
+ HeapTuple tuple;
+ Form_pg_type typtuple;
+
+ tuple = SearchSysCache(TYPEOID,
+ ObjectIdGetDatum(typeoid),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(tuple))
+ elog(ERROR, "cache lookup failed for type %u", typeoid);
+ typtuple = (Form_pg_type) GETSTRUCT(tuple);
+
+ appendStringInfoString(&result,
+ map_multipart_sql_identifier_to_xml_name((typtuple->typtype == TYPTYPE_DOMAIN) ? "Domain" : "UDT",
+ get_database_name(MyDatabaseId),
+ get_namespace_name(typtuple->typnamespace),
+ NameStr(typtuple->typname)));
+
+ ReleaseSysCache(tuple);
+ }
+ }
+
+ return result.data;
+}
+
+
+/*
+ * Map a collection of SQL data types to XML Schema data types; see
+ * SQL/XML:2002 section 9.10.
+ */
+static const char *
+map_sql_typecoll_to_xmlschema_types(List *tupdesc_list)
+{
+ List *uniquetypes = NIL;
+ int i;
+ StringInfoData result;
+ ListCell *cell0;
+
+ /* extract all column types used in the set of TupleDescs */
+ foreach(cell0, tupdesc_list)
+ {
+ TupleDesc tupdesc = (TupleDesc) lfirst(cell0);
+
+ for (i = 0; i < tupdesc->natts; i++)
+ {
+ if (tupdesc->attrs[i]->attisdropped)
+ continue;
+ uniquetypes = list_append_unique_oid(uniquetypes,
+ tupdesc->attrs[i]->atttypid);
+ }
+ }
+
+ /* add base types of domains */
+ foreach(cell0, uniquetypes)
+ {
+ Oid typid = lfirst_oid(cell0);
+ Oid basetypid = getBaseType(typid);
+
+ if (basetypid != typid)
+ uniquetypes = list_append_unique_oid(uniquetypes, basetypid);
+ }
+
+ /* Convert to textual form */
+ initStringInfo(&result);
+
+ foreach(cell0, uniquetypes)
+ {
+ appendStringInfo(&result, "%s\n",
+ map_sql_type_to_xmlschema_type(lfirst_oid(cell0),
+ -1));
+ }
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL data type to a named XML Schema data type; see SQL/XML
+ * sections 9.11 and 9.15.
+ *
+ * (The distinction between 9.11 and 9.15 is basically that 9.15 adds
+ * a name attribute, which this function does. The name-less version
+ * 9.11 doesn't appear to be required anywhere.)
+ */
+static const char *
+map_sql_type_to_xmlschema_type(Oid typeoid, int typmod)
+{
+ StringInfoData result;
+ const char *typename = map_sql_type_to_xml_name(typeoid, typmod);
+
+ initStringInfo(&result);
+
+ if (typeoid == XMLOID)
+ {
+ appendStringInfo(&result,
+ "<xsd:complexType mixed=\"true\">\n"
+ " <xsd:sequence>\n"
+ " <xsd:any name=\"element\" minOccurs=\"0\" maxOccurs=\"unbounded\" processContents=\"skip\"/>\n"
+ " </xsd:sequence>\n"
+ "</xsd:complexType>\n");
+ }
+ else
+ {
+ appendStringInfo(&result,
+ "<xsd:simpleType name=\"%s\">\n", typename);
+
+ switch (typeoid)
+ {
+ case BPCHAROID:
+ case VARCHAROID:
+ case TEXTOID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:string\">\n");
+ if (typmod != -1)
+ appendStringInfo(&result,
+ " <xsd:maxLength value=\"%d\"/>\n",
+ typmod - VARHDRSZ);
+ appendStringInfo(&result,
+ " </xsd:restriction>\n");
+ break;
+
+ case BYTEAOID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:%s\">\n"
+ " </xsd:restriction>\n",
+ xmlbinary == XMLBINARY_BASE64 ? "base64Binary" : "hexBinary");
+ break;
+
+ case NUMERICOID:
+ if (typmod != -1)
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:decimal\">\n"
+ " <xsd:totalDigits value=\"%d\"/>\n"
+ " <xsd:fractionDigits value=\"%d\"/>\n"
+ " </xsd:restriction>\n",
+ ((typmod - VARHDRSZ) >> 16) & 0xffff,
+ (typmod - VARHDRSZ) & 0xffff);
+ break;
+
+ case INT2OID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:short\">\n"
+ " <xsd:maxInclusive value=\"%d\"/>\n"
+ " <xsd:minInclusive value=\"%d\"/>\n"
+ " </xsd:restriction>\n",
+ SHRT_MAX, SHRT_MIN);
+ break;
+
+ case INT4OID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:int\">\n"
+ " <xsd:maxInclusive value=\"%d\"/>\n"
+ " <xsd:minInclusive value=\"%d\"/>\n"
+ " </xsd:restriction>\n",
+ INT_MAX, INT_MIN);
+ break;
+
+ case INT8OID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:long\">\n"
+ " <xsd:maxInclusive value=\"" INT64_FORMAT "\"/>\n"
+ " <xsd:minInclusive value=\"" INT64_FORMAT "\"/>\n"
+ " </xsd:restriction>\n",
+ (((uint64) 1) << (sizeof(int64) * 8 - 1)) - 1,
+ (((uint64) 1) << (sizeof(int64) * 8 - 1)));
+ break;
+
+ case FLOAT4OID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:float\"></xsd:restriction>\n");
+ break;
+
+ case FLOAT8OID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:double\"></xsd:restriction>\n");
+ break;
+
+ case BOOLOID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:boolean\"></xsd:restriction>\n");
+ break;
+
+ case TIMEOID:
+ case TIMETZOID:
+ {
+ const char *tz = (typeoid == TIMETZOID ? "(+|-)\\p{Nd}{2}:\\p{Nd}{2}" : "");
+
+ if (typmod == -1)
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:time\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}(.\\p{Nd}+)?%s\"/>\n"
+ " </xsd:restriction>\n", tz);
+ else if (typmod == 0)
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:time\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}%s\"/>\n"
+ " </xsd:restriction>\n", tz);
+ else
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:time\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}.\\p{Nd}{%d}%s\"/>\n"
+ " </xsd:restriction>\n", typmod - VARHDRSZ, tz);
+ break;
+ }
+
+ case TIMESTAMPOID:
+ case TIMESTAMPTZOID:
+ {
+ const char *tz = (typeoid == TIMESTAMPTZOID ? "(+|-)\\p{Nd}{2}:\\p{Nd}{2}" : "");
+
+ if (typmod == -1)
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:dateTime\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{4}-\\p{Nd}{2}-\\p{Nd}{2}T\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}(.\\p{Nd}+)?%s\"/>\n"
+ " </xsd:restriction>\n", tz);
+ else if (typmod == 0)
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:dateTime\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{4}-\\p{Nd}{2}-\\p{Nd}{2}T\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}%s\"/>\n"
+ " </xsd:restriction>\n", tz);
+ else
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:dateTime\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{4}-\\p{Nd}{2}-\\p{Nd}{2}T\\p{Nd}{2}:\\p{Nd}{2}:\\p{Nd}{2}.\\p{Nd}{%d}%s\"/>\n"
+ " </xsd:restriction>\n", typmod - VARHDRSZ, tz);
+ break;
+ }
+
+ case DATEOID:
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"xsd:date\">\n"
+ " <xsd:pattern value=\"\\p{Nd}{4}-\\p{Nd}{2}-\\p{Nd}{2}\"/>\n"
+ " </xsd:restriction>\n");
+ break;
+
+ default:
+ if (get_typtype(typeoid) == TYPTYPE_DOMAIN)
+ {
+ Oid base_typeoid;
+ int32 base_typmod = -1;
+
+ base_typeoid = getBaseTypeAndTypmod(typeoid, &base_typmod);
+
+ appendStringInfo(&result,
+ " <xsd:restriction base=\"%s\"/>\n",
+ map_sql_type_to_xml_name(base_typeoid, base_typmod));
+ }
+ break;
+ }
+ appendStringInfo(&result,
+ "</xsd:simpleType>\n");
+ }
+
+ return result.data;
+}
+
+
+/*
+ * Map an SQL row to an XML element, taking the row from the active
+ * SPI cursor. See also SQL/XML:2003 section 9.12.
+ */
+static void
+SPI_sql_row_to_xmlelement(int rownum, StringInfo result, char *tablename,
+ bool nulls, bool tableforest,
+ const char *targetns, bool top_level)
+{
+ int i;
+ char *xmltn;
+
+ if (tablename)
+ xmltn = map_sql_identifier_to_xml_name(tablename, true, false);
+ else
+ {
+ if (tableforest)
+ xmltn = "row";
+ else
+ xmltn = "table";
+ }
+
+ if (tableforest)
+ xmldata_root_element_start(result, xmltn, NULL, targetns, top_level);
+ else
+ appendStringInfoString(result, "<row>\n");
+
+ for (i = 1; i <= SPI_tuptable->tupdesc->natts; i++)
+ {
+ char *colname;
+ Datum colval;
+ bool isnull;
+
+ colname = map_sql_identifier_to_xml_name(SPI_fname(SPI_tuptable->tupdesc, i),
+ true, false);
+ colval = SPI_getbinval(SPI_tuptable->vals[rownum],
+ SPI_tuptable->tupdesc,
+ i,
+ &isnull);
+ if (isnull)
+ {
+ if (nulls)
+ appendStringInfo(result, " <%s xsi:nil=\"true\"/>\n", colname);
+ }
+ else
+ appendStringInfo(result, " <%s>%s</%s>\n",
+ colname,
+ map_sql_value_to_xml_value(colval,
+ SPI_gettypeid(SPI_tuptable->tupdesc, i)),
+ colname);
+ }
+
+ if (tableforest)
+ {
+ xmldata_root_element_end(result, xmltn);
+ appendStringInfoChar(result, '\n');
+ }
+ else
+ appendStringInfoString(result, "</row>\n\n");
+}
+
+
+/*
+ * XPath related functions
+ */
+
+#ifdef USE_LIBXML
+/*
+ * Convert XML node to text (dump subtree in case of element,
+ * return value otherwise)
+ */
+static text *
+xml_xmlnodetoxmltype(xmlNodePtr cur)
+{
+ xmlChar *str;
+ xmltype *result;
+ xmlBufferPtr buf;
+
+ if (cur->type == XML_ELEMENT_NODE)
+ {
+ buf = xmlBufferCreate();
+ xmlNodeDump(buf, NULL, cur, 0, 1);
+ result = xmlBuffer_to_xmltype(buf);
+ xmlBufferFree(buf);
+ }
+ else
+ {
+ str = xmlXPathCastNodeToString(cur);
+ result = (xmltype *) cstring_to_text((char *) str);
+ xmlFree(str);
+ }
+
+ return result;
+}
+#endif
+
+
+/*
+ * Evaluate XPath expression and return array of XML values.
+ *
+ * As we have no support of XQuery sequences yet, this function seems
+ * to be the most useful one (array of XML functions plays a role of
+ * some kind of substitution for XQuery sequences).
+ *
+ * Workaround here: we parse XML data in different way to allow XPath for
+ * fragments (see "XPath for fragment" TODO comment inside).
+ */
+Datum
+xpath(PG_FUNCTION_ARGS)
+{
+#ifdef USE_LIBXML
+ text *xpath_expr_text = PG_GETARG_TEXT_P(0);
+ xmltype *data = PG_GETARG_XML_P(1);
+ ArrayType *namespaces = PG_GETARG_ARRAYTYPE_P(2);
+ ArrayBuildState *astate = NULL;
+ xmlParserCtxtPtr ctxt;
+ xmlDocPtr doc;
+ xmlXPathContextPtr xpathctx;
+ xmlXPathCompExprPtr xpathcomp;
+ xmlXPathObjectPtr xpathobj;
+ char *datastr;
+ int32 len;
+ int32 xpath_len;
+ xmlChar *string;
+ xmlChar *xpath_expr;
+ int i;
+ int res_nitems;
+ int ndim;
+ Datum *ns_names_uris;
+ bool *ns_names_uris_nulls;
+ int ns_count;
+
+ /*
+ * Namespace mappings are passed as text[]. If an empty array is passed
+ * (ndim = 0, "0-dimensional"), then there are no namespace mappings.
+ * Else, a 2-dimensional array with length of the second axis being equal
+ * to 2 should be passed, i.e., every subarray contains 2 elements, the
+ * first element defining the name, the second one the URI. Example:
+ * ARRAY[ARRAY['myns', 'http://example.com'], ARRAY['myns2',
+ * 'http://example2.com']].
+ */
+ ndim = ARR_NDIM(namespaces);
+ if (ndim != 0)
+ {
+ int *dims;
+
+ dims = ARR_DIMS(namespaces);
+
+ if (ndim != 2 || dims[1] != 2)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_EXCEPTION),
+ errmsg("invalid array for XML namespace mapping"),
+ errdetail("The array must be two-dimensional with length of the second axis equal to 2.")));
+
+ Assert(ARR_ELEMTYPE(namespaces) == TEXTOID);
+
+ deconstruct_array(namespaces, TEXTOID, -1, false, 'i',
+ &ns_names_uris, &ns_names_uris_nulls,
+ &ns_count);
+
+ Assert((ns_count % 2) == 0); /* checked above */
+ ns_count /= 2; /* count pairs only */
+ }
+ else
+ {
+ ns_names_uris = NULL;
+ ns_names_uris_nulls = NULL;
+ ns_count = 0;
+ }
+
+ datastr = VARDATA(data);
+ len = VARSIZE(data) - VARHDRSZ;
+ xpath_len = VARSIZE(xpath_expr_text) - VARHDRSZ;
+ if (xpath_len == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATA_EXCEPTION),
+ errmsg("empty XPath expression")));
+
+ xml_init();
+
+ /*
+ * To handle both documents and fragments, regardless of the fact whether
+ * the XML datum has a single root (XML well-formedness), we wrap the XML
+ * datum in a dummy element (<x>...</x>) and extend the XPath expression
+ * accordingly. To do it, throw away the XML prolog, if any.
+ */
+ if (len >= 5 &&
+ xmlStrncmp((xmlChar *) datastr, (xmlChar *) "<?xml", 5) == 0)
+ {
+ i = 5;
+ while (i < len &&
+ !(datastr[i - 1] == '?' && datastr[i] == '>'))
+ i++;
+
+ if (i == len)
+ xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
+ "could not parse XML data");
+
+ ++i;
+
+ datastr += i;
+ len -= i;
+ }
+
+ string = (xmlChar *) palloc((len + 8) * sizeof(xmlChar));
+ memcpy(string, "<x>", 3);
+ memcpy(string + 3, datastr, len);
+ memcpy(string + 3 + len, "</x>", 5);
+ len += 7;
+
+ xpath_expr = (xmlChar *) palloc((xpath_len + 3) * sizeof(xmlChar));
+ memcpy(xpath_expr, "/x", 2);
+ memcpy(xpath_expr + 2, VARDATA(xpath_expr_text), xpath_len);
+ xpath_expr[xpath_len + 2] = '\0';
+ xpath_len += 2;
+
+ xmlInitParser();
+
+ /*
+ * redundant XML parsing (two parsings for the same value during one
+ * command execution are possible)
+ */
+ ctxt = xmlNewParserCtxt();
+ if (ctxt == NULL)
+ xml_ereport(ERROR, ERRCODE_OUT_OF_MEMORY,
+ "could not allocate parser context");
+ doc = xmlCtxtReadMemory(ctxt, (char *) string, len, NULL, NULL, 0);
+ if (doc == NULL)
+ xml_ereport(ERROR, ERRCODE_INVALID_XML_DOCUMENT,
+ "could not parse XML data");
+ xpathctx = xmlXPathNewContext(doc);
+ if (xpathctx == NULL)
+ xml_ereport(ERROR, ERRCODE_OUT_OF_MEMORY,
+ "could not allocate XPath context");
+ xpathctx->node = xmlDocGetRootElement(doc);
+ if (xpathctx->node == NULL)
+ xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
+ "could not find root XML element");
+
+ /* register namespaces, if any */
+ if (ns_count > 0)
+ {
+ for (i = 0; i < ns_count; i++)
+ {
+ char *ns_name;
+ char *ns_uri;
+
+ if (ns_names_uris_nulls[i * 2] ||
+ ns_names_uris_nulls[i * 2 + 1])
+ ereport(ERROR,
+ (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
+ errmsg("neither namespace name nor URI may be null")));
+ ns_name = TextDatumGetCString(ns_names_uris[i * 2]);
+ ns_uri = TextDatumGetCString(ns_names_uris[i * 2 + 1]);
+ if (xmlXPathRegisterNs(xpathctx,
+ (xmlChar *) ns_name,
+ (xmlChar *) ns_uri) != 0)
+ ereport(ERROR, /* is this an internal error??? */
+ (errmsg("could not register XML namespace with name \"%s\" and URI \"%s\"",
+ ns_name, ns_uri)));
+ }
+ }
+
+ xpathcomp = xmlXPathCompile(xpath_expr);
+ if (xpathcomp == NULL) /* TODO: show proper XPath error details */
+ xml_ereport(ERROR, ERRCODE_INTERNAL_ERROR,
+ "invalid XPath expression");
+
+ xpathobj = xmlXPathCompiledEval(xpathcomp, xpathctx);
+ if (xpathobj == NULL) /* TODO: reason? */
+ ereport(ERROR,
+ (errmsg("could not create XPath object")));
+
+ xmlXPathFreeCompExpr(xpathcomp);
+
+ /* return empty array in cases when nothing is found */
+ if (xpathobj->nodesetval == NULL)
+ res_nitems = 0;
+ else
+ res_nitems = xpathobj->nodesetval->nodeNr;
+
+ if (res_nitems)
+ {
+ for (i = 0; i < xpathobj->nodesetval->nodeNr; i++)
+ {
+ Datum elem;
+ bool elemisnull = false;
+
+ elem = PointerGetDatum(xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i]));
+ astate = accumArrayResult(astate, elem,
+ elemisnull, XMLOID,
+ CurrentMemoryContext);
+ }
+ }
+
+ xmlXPathFreeObject(xpathobj);
+ xmlXPathFreeContext(xpathctx);
+ xmlFreeDoc(doc);
+ xmlFreeParserCtxt(ctxt);
+
+ if (res_nitems == 0)
+ PG_RETURN_ARRAYTYPE_P(construct_empty_array(XMLOID));
+ else
+ PG_RETURN_ARRAYTYPE_P(makeArrayResult(astate, CurrentMemoryContext));
+#else
+ NO_XML_SUPPORT();
+ return 0;
+#endif
+}