*
* xml.c
* XML data type support.
*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/backend/utils/adt/xml.c
*
* -------------------------------------------------------------------------
*/
* Generally, XML type support is only available when libxml use was
* configured during the build. But even if that is not done, the
* type and all the functions are available, but most of them will
* 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
* else does.
*/
* Notes on memory management:
*
* Sometimes libxml allocates global structures in the hope that it can reuse
* them later on. This makes it impractical to change the xmlMemSetup
* functions on-the-fly; that is likely to lead to trying to pfree_ext() chunks
* allocated with malloc() or vice versa. Since libxml might be used by
* loadable modules, eg libperl, our only safe choices are to change the
* functions at postmaster/backend launch or not at all. Since we'd rather
* not activate libxml in sessions that might never use it, the latter choice
* is the preferred one. However, for debugging purposes it can be awfully
* handy to constrain libxml's allocations to be done in a specific palloc
* context, where they're easy to track. Therefore there is code here that
* can be enabled in debug builds to redirect libxml's allocations into a
* special context LibxmlContext. It's not recommended to turn this on in
* a production build because of the possibility of bad interactions with
* external modules.
*/
#include "postgres.h"
#include "knl/knl_variable.h"
#ifdef USE_LIBXML
#include <libxml/chvalid.h>
#include <libxml/parser.h>
#include <libxml/parserInternals.h>
#include <libxml/tree.h>
#include <libxml/uri.h>
#include <libxml/xmlerror.h>
#include <libxml/xmlversion.h>
#include <libxml/xmlwriter.h>
#include <libxml/xpath.h>
#include <libxml/xpathInternals.h>
* We used to check for xmlStructuredErrorContext via a configure test; but
* that doesn't work on Windows, so instead use this grottier method of
* testing the library version number.
*/
#if LIBXML_VERSION >= 20704
#define HAVE_XMLSTRUCTUREDERRORCONTEXT 1
#endif
#endif
#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 "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/rel.h"
#include "utils/rel_gs.h"
#include "utils/syscache.h"
#include "utils/xml.h"
THR_LOCAL int xmloption;
#ifdef USE_LIBXML
#define ERRCXT_MAGIC 68275028
struct PgXmlErrorContext {
int magic;
PgXmlStrictness strictness;
bool err_occurred;
StringInfoData err_buf;
xmlStructuredErrorFunc saved_errfunc;
void* saved_errcxt;
xmlExternalEntityLoader saved_entityfunc;
};
static xmlParserInputPtr xmlPgEntityLoader(const char* URL, const char* ID, xmlParserCtxtPtr ctxt);
static void xml_error_handler(void* data, xmlErrorPtr error);
static void xml_ereport_by_code(int level, int sqlcode, const char* msg, int errcode);
static void chopStringInfoNewlines(StringInfo str);
static void appendStringInfoLineSeparator(StringInfo str);
#ifdef USE_LIBXMLCONTEXT
static MemoryContext LibxmlContext = NULL;
static void xml_memory_init(void);
static void* xml_palloc(size_t size);
static void* xml_repalloc(void* ptr, size_t size);
static void xml_pfree_ext(void* ptr);
static char* xml_pstrdup(const char* string);
#endif
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, XmlOptionType xmloption_arg, bool preserve_whitespace, int encoding,
bool can_ignore = false, bool try_another_parse_mode = false);
static text* xml_xmlnodetoxmltype(xmlNodePtr cur);
static int xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj, ArrayBuildState** astate, PgXmlErrorContext *xmlerrcxt);
#endif
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);
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 DEF_TARGETNS ""
#ifdef USE_LIBXML
#define NO_XML_SUPPORT()
#else
#define NO_XML_SUPPORT() \
ereport(ERROR, \
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), \
errmsg("unsupported XML feature"), \
errdetail("This functionality requires the server to be built with libxml support.")))
#endif
#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(const xmlChar* encoding_name)
{
int encoding = pg_char_to_encoding((const char*)encoding_name);
if (encoding < 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid encoding name \"%s\"", (const 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);
xmltype* vardata = NULL;
xmlDocPtr doc;
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.
*/
doc = xml_parse(vardata, (XmlOptionType)xmloption, true, GetDatabaseEncoding(), fcinfo->can_ignore, true);
xmlFreeDoc(doc);
PG_RETURN_XML_P(vardata);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
#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 = text_to_cstring((text*)x);
#ifdef USE_LIBXML
size_t len = strlen(str);
xmlChar* version = NULL;
int standalone;
int res_code;
if ((res_code = parse_xml_decl((xmlChar*)str, &len, &version, NULL, &standalone)) == 0) {
StringInfoData buf;
initStringInfo(&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 (*(str + len) == '\n')
len += 1;
}
appendStringInfoString(&buf, str + len);
pfree_ext(str);
return buf.data;
}
xml_ereport_by_code(
WARNING, ERRCODE_INVALID_XML_CONTENT, "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);
* 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, (pg_enc)0));
}
Datum xml_recv(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
StringInfo buf = (StringInfo)PG_GETARG_POINTER(0);
xmltype* result = NULL;
char* str = NULL;
char* newstr = NULL;
int nbytes;
xmlDocPtr doc;
xmlChar* encodingStr = NULL;
int encoding;
* 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);
* 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 = (xmltype*)palloc(nbytes + 1 + VARHDRSZ);
SET_VARSIZE(result, nbytes + VARHDRSZ);
int rc = memcpy_s(VARDATA(result), nbytes, str, nbytes);
securec_check(rc, "\0", "\0");
str = VARDATA(result);
str[nbytes] = '\0';
int res_code = parse_xml_decl((const xmlChar*)str, NULL, NULL, &encodingStr, NULL);
if (res_code != 0)
xml_ereport_by_code(
ERROR, ERRCODE_INVALID_XML_CONTENT, "invalid XML content: invalid XML declaration", res_code);
* If encoding wasn't explicitly specified in the XML header, treat it as
* UTF-8, as that's the default in XML. This is different from xml_in(),
* where the input has to go through the normal client to server encoding
* conversion.
*/
encoding = encodingStr ? xmlChar_to_encoding(encodingStr) : PG_UTF8;
* 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, (XmlOptionType)xmloption, true, encoding);
xmlFreeDoc(doc);
newstr = (char*)pg_do_encoding_conversion((unsigned char*)str, nbytes, encoding, GetDatabaseEncoding());
if (newstr != str) {
pfree_ext(result);
result = (xmltype*)cstring_to_text(newstr);
pfree_ext(newstr);
}
PG_RETURN_XML_P(result);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xml_send(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
xmltype* x = PG_GETARG_XML_P(0);
char* outval = NULL;
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_enc)pg_get_client_encoding());
pq_begintypsend(&buf);
pq_sendtext(&buf, outval, strlen(outval));
pfree_ext(outval);
PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}
#ifdef USE_LIBXML
static void appendStringInfoText(StringInfo str, const text* t)
{
appendBinaryStringInfo(str, VARDATA(t), VARSIZE(t) - VARHDRSZ);
}
#endif
xmltype* stringinfo_to_xmltype(StringInfo buf)
{
return (xmltype*)cstring_to_text_with_len(buf->data, buf->len);
}
static xmltype* cstring_to_xmltype(const char* string)
{
return (xmltype*)cstring_to_text(string);
}
#ifdef USE_LIBXML
static xmltype* xmlBuffer_to_xmltype(xmlBufferPtr buf)
{
return (xmltype*)cstring_to_text_with_len((const char*)xmlBufferContent(buf), xmlBufferLength(buf));
}
#endif
Datum xmlcomment(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
text* arg = PG_GETARG_TEXT_P(0);
char* argdata = VARDATA(arg);
int len = VARSIZE(arg) - VARHDRSZ;
StringInfoData buf;
int i;
for (i = 1; i < len; i++) {
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, "<!--");
appendStringInfoText(&buf, arg);
appendStringInfo(&buf, "-->");
PG_RETURN_XML_P(stringinfo_to_xmltype(&buf));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
* Xmlconcat needs to merge the notations and unparsed entities
* of the argument values. Not very important in practice, though.
*/
xmltype* xmlconcat(List* args)
{
#ifdef USE_LIBXML
int global_standalone = 1;
xmlChar* global_version = NULL;
bool global_version_no_value = false;
StringInfoData buf;
ListCell* v = NULL;
initStringInfo(&buf);
foreach (v, args) {
xmltype* x = DatumGetXmlP(PointerGetDatum(lfirst(v)));
size_t len;
xmlChar* version = NULL;
int standalone;
char* str = NULL;
len = VARSIZE(x) - VARHDRSZ;
str = text_to_cstring((text*)x);
int res_code = parse_xml_decl((xmlChar*)str, &len, &version, NULL, &standalone);
if (res_code != 0)
xml_ereport_by_code(
ERROR, ERRCODE_INVALID_XML_CONTENT, "invalid XML content: invalid XML declaration", res_code);
if (standalone == 0 && global_standalone == 1)
global_standalone = 0;
if (standalone < 0)
global_standalone = -1;
if (version == NULL)
global_version_no_value = true;
else if (global_version == NULL)
global_version = version;
else if (xmlStrcmp(version, global_version) != 0)
global_version_no_value = true;
appendStringInfoString(&buf, str + len);
pfree_ext(str);
}
if (!global_version_no_value || global_standalone >= 0) {
StringInfoData buf2;
initStringInfo(&buf2);
print_xml_decl(&buf2, (!global_version_no_value) ? global_version : NULL, (pg_enc)0, global_standalone);
appendStringInfoString(&buf2, buf.data);
buf = buf2;
}
return stringinfo_to_xmltype(&buf);
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
* XMLAGG support
*/
Datum xmlconcat2(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
if (PG_ARGISNULL(0)) {
if (PG_ARGISNULL(1))
PG_RETURN_NULL();
else
PG_RETURN_XML_P(PG_GETARG_XML_P(1));
} 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))));
}
Datum texttoxml(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
text* data = PG_GETARG_TEXT_P(0);
PG_RETURN_XML_P(xmlparse(data, (XmlOptionType)xmloption, true));
}
Datum xmltotext(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
xmltype* data = PG_GETARG_XML_P(0);
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")));
return (text*)data;
}
xmltype* xmlelement(XmlExprState* xmlExpr, ExprContext* econtext)
{
#ifdef USE_LIBXML
XmlExpr* xexpr = (XmlExpr*)xmlExpr->xprstate.expr;
xmltype* result = NULL;
List* named_arg_strings = NIL;
List* arg_strings = NIL;
ListCell* arg = NULL;
ListCell* narg = NULL;
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlBufferPtr buf = NULL;
volatile xmlTextWriterPtr writer = NULL;
* 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;
foreach (arg, xmlExpr->named_args) {
ExprState* e = (ExprState*)lfirst(arg);
Datum value;
bool isnull = false;
char* str = NULL;
value = ExecEvalExpr(e, econtext, &isnull, NULL);
if (isnull)
str = NULL;
else
str = map_sql_value_to_xml_value(value, exprType((Node*)e->expr), false);
named_arg_strings = lappend(named_arg_strings, str);
}
arg_strings = NIL;
foreach (arg, xmlExpr->args) {
ExprState* e = (ExprState*)lfirst(arg);
Datum value;
bool isnull = false;
char* str = NULL;
value = ExecEvalExpr(e, econtext, &isnull, NULL);
if (!isnull) {
str = map_sql_value_to_xml_value(value, exprType((Node*)e->expr), true);
arg_strings = lappend(arg_strings, str);
}
}
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
buf = xmlBufferCreate();
if (buf == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlBuffer");
writer = xmlNewTextWriterMemory(buf, 0);
if (writer == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlTextWriter");
xmlTextWriterStartElement(writer, (xmlChar*)xexpr->name);
forboth(arg, named_arg_strings, narg, xexpr->arg_names)
{
char* str = (char*)lfirst(arg);
char* argname = strVal(lfirst(narg));
if (str != NULL)
xmlTextWriterWriteAttribute(writer, (xmlChar*)argname, (xmlChar*)str);
}
foreach (arg, arg_strings) {
char* str = (char*)lfirst(arg);
xmlTextWriterWriteRaw(writer, (xmlChar*)str);
}
xmlTextWriterEndElement(writer);
xmlFreeTextWriter(writer);
writer = NULL;
result = xmlBuffer_to_xmltype(buf);
}
PG_CATCH();
{
if (writer)
xmlFreeTextWriter(writer);
if (buf)
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, false);
return result;
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
xmltype* xmlelementByFlatten(XmlExpr *xexpr,
Datum *named_argvalue, bool *named_argnull,
Datum *argvalue, bool *argnull)
{
#ifdef USE_LIBXML
xmltype* result = NULL;
List* named_arg_strings = NIL;
List* arg_strings = NIL;
int i;
ListCell* arg = NULL;
ListCell* narg = NULL;
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlBufferPtr buf = NULL;
volatile xmlTextWriterPtr writer = NULL;
* All arguments are already evaluated, and their values are passed in the
* named_argvalue/named_argnull or argvalue/argnull arrays. 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. We examine the
* original XmlExpr to identify the numbers and types of the arguments.
*/
named_arg_strings = NIL;
i = 0;
foreach(arg, xexpr->named_args)
{
Expr *e = (Expr *) lfirst(arg);
char* str = NULL;
if (named_argnull[i])
str = NULL;
else
str = map_sql_value_to_xml_value(named_argvalue[i], exprType((Node *)e), false);
named_arg_strings = lappend(named_arg_strings, str);
i++;
}
i = 0;
arg_strings = NIL;
i = 0;
foreach(arg, xexpr->args)
{
Expr *e = (Expr *) lfirst(arg);
char* str = NULL;
if (!argnull[i])
{
str = map_sql_value_to_xml_value(argvalue[i], exprType((Node *)e), true);
arg_strings = lappend(arg_strings, str);
}
i++;
}
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
buf = xmlBufferCreate();
if (buf == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlBuffer");
writer = xmlNewTextWriterMemory(buf, 0);
if (writer == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlTextWriter");
xmlTextWriterStartElement(writer, (xmlChar*)xexpr->name);
forboth(arg, named_arg_strings, narg, xexpr->arg_names)
{
char* str = (char*)lfirst(arg);
char* argname = strVal(lfirst(narg));
if (str != NULL)
xmlTextWriterWriteAttribute(writer, (xmlChar*)argname, (xmlChar*)str);
}
foreach (arg, arg_strings) {
char* str = (char*)lfirst(arg);
xmlTextWriterWriteRaw(writer, (xmlChar*)str);
}
xmlTextWriterEndElement(writer);
xmlFreeTextWriter(writer);
writer = NULL;
result = xmlBuffer_to_xmltype(buf);
}
PG_CATCH();
{
if (writer)
xmlFreeTextWriter(writer);
if (buf)
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, false);
return result;
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
xmltype* xmlparse(text* data, XmlOptionType xmloption_arg, bool preserve_whitespace)
{
#ifdef USE_LIBXML
xmlDocPtr doc;
doc = xml_parse(data, xmloption_arg, preserve_whitespace, GetDatabaseEncoding());
xmlFreeDoc(doc);
return (xmltype*)data;
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
xmltype* xmlpi(char* target, text* arg, bool arg_is_null, bool* result_is_null)
{
#ifdef USE_LIBXML
xmltype* result = NULL;
StringInfoData buf;
if (pg_strcasecmp(target, "xml") == 0)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid XML processing instruction"),
errdetail("XML processing instruction target name cannot be \"%s\".", target)));
* 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;
initStringInfo(&buf);
appendStringInfo(&buf, "<?%s", target);
if (arg != NULL) {
char* string = NULL;
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 \"?>\".")));
appendStringInfoChar(&buf, ' ');
appendStringInfoString(&buf, string + strspn(string, " "));
pfree_ext(string);
}
appendStringInfoString(&buf, "?>");
result = stringinfo_to_xmltype(&buf);
pfree_ext(buf.data);
return result;
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
xmltype* xmlroot(xmltype* data, text* version, int standalone)
{
#ifdef USE_LIBXML
char* str = NULL;
size_t len;
xmlChar* orig_version = NULL;
int orig_standalone;
StringInfoData buf;
len = VARSIZE(data) - VARHDRSZ;
str = text_to_cstring((text*)data);
int res_code = parse_xml_decl((xmlChar*)str, &len, &orig_version, NULL, &orig_standalone);
if (res_code != 0)
xml_ereport_by_code(
ERROR, ERRCODE_INVALID_XML_CONTENT, "invalid XML content: invalid XML declaration", res_code);
if (version != NULL)
orig_version = xml_text2xmlChar(version);
else
orig_version = NULL;
switch (standalone) {
case XML_STANDALONE_YES:
orig_standalone = 1;
break;
case XML_STANDALONE_NO:
orig_standalone = 0;
break;
case XML_STANDALONE_NO_VALUE:
orig_standalone = -1;
break;
case XML_STANDALONE_OMITTED:
break;
default:
break;
}
initStringInfo(&buf);
print_xml_decl(&buf, orig_version, (pg_enc)0, orig_standalone);
appendStringInfoString(&buf, str + len);
return stringinfo_to_xmltype(&buf);
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
* Validate document (given as string) against DTD (given as external link)
*
* 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)
{
ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("xmlvalidate is not implemented")));
return 0;
}
bool xml_is_document(xmltype* arg)
{
#ifdef USE_LIBXML
bool result = false;
volatile xmlDocPtr doc = NULL;
MemoryContext ccxt = CurrentMemoryContext;
PG_TRY();
{
doc = xml_parse((text*)arg, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
result = true;
}
PG_CATCH();
{
ErrorData* errdata = NULL;
MemoryContext ecxt;
ecxt = MemoryContextSwitchTo(ccxt);
errdata = CopyErrorData();
if (errdata->sqlerrcode == ERRCODE_INVALID_XML_DOCUMENT) {
FlushErrorState();
result = false;
} else {
MemoryContextSwitchTo(ecxt);
PG_RE_THROW();
}
}
PG_END_TRY();
if (doc)
xmlFreeDoc(doc);
return result;
#else
NO_XML_SUPPORT();
return false;
#endif
}
#ifdef USE_LIBXML
* pg_xml_init_library --- set up for use of libxml
*
* This should be called by each function that is about to use libxml
* facilities but doesn't require error handling. It initializes libxml
* and verifies compatibility with the loaded libxml version. These are
* once-per-session activities.
*
* XmlChar is utf8-char, need make proper tuning (initdb with enc!=utf8 and
* check)
*/
void pg_xml_init_library(void)
{
static bool first_time = true;
if (first_time) {
* Currently, we have no pure UTF-8 support for internals -- check if
* we can work.
*/
if (sizeof(char) != sizeof(xmlChar))
ereport(ERROR, (errcode(ERRCODE_DATATYPE_MISMATCH), errmsg("could not initialize XML library"),
errdetail("libxml2 has incompatible char type: sizeof(char)=%d, sizeof(xmlChar)=%d.",
(int)sizeof(char), (int)sizeof(xmlChar))));
#ifdef USE_LIBXMLCONTEXT
xml_memory_init();
#endif
LIBXML_TEST_VERSION;
first_time = false;
}
}
* pg_xml_init --- set up for use of libxml and register an error handler
*
* This should be called by each function that is about to use libxml
* facilities and requires error handling. It initializes libxml with
* pg_xml_init_library() and establishes our libxml error handler.
*
* strictness determines which errors are reported and which are ignored.
*
* Calls to this function MUST be followed by a PG_TRY block that guarantees
* that pg_xml_done() is called during either normal or error exit.
*
* This is exported for use by contrib/xml2, as well as other code that might
* wish to share use of this module's libxml error handler.
*/
PgXmlErrorContext* pg_xml_init(PgXmlStrictness strictness)
{
PgXmlErrorContext* errcxt = NULL;
void* new_errcxt = NULL;
pg_xml_init_library();
errcxt = (PgXmlErrorContext*)palloc(sizeof(PgXmlErrorContext));
errcxt->magic = ERRCXT_MAGIC;
errcxt->strictness = strictness;
errcxt->err_occurred = false;
initStringInfo(&errcxt->err_buf);
* Save original error handler and install ours. libxml originally didn't
* distinguish between the contexts for generic and for structured error
* handlers. If we're using an old libxml version, we must thus save the
* generic error context, even though we're using a structured error
* handler.
*/
errcxt->saved_errfunc = xmlStructuredError;
#ifdef HAVE_XMLSTRUCTUREDERRORCONTEXT
errcxt->saved_errcxt = xmlStructuredErrorContext;
#else
errcxt->saved_errcxt = xmlGenericErrorContext;
#endif
xmlSetStructuredErrorFunc((void*)errcxt, xml_error_handler);
* Verify that xmlSetStructuredErrorFunc set the context variable we
* expected it to. If not, the error context pointer we just saved is not
* the correct thing to restore, and since that leaves us without a way to
* restore the context in pg_xml_done, we must fail.
*
* The only known situation in which this test fails is if we compile with
* headers from a libxml2 that doesn't track the structured error context
* separately (< 2.7.4), but at runtime use a version that does, or vice
* versa. The libxml2 authors did not treat that change as constituting
* an ABI break, so the LIBXML_TEST_VERSION test in pg_xml_init_library
* fails to protect us from this.
*/
#ifdef HAVE_XMLSTRUCTUREDERRORCONTEXT
new_errcxt = xmlStructuredErrorContext;
#else
new_errcxt = xmlGenericErrorContext;
#endif
if (new_errcxt != (void*)errcxt)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("could not set up XML error handler"),
errhint("This probably indicates that the version of libxml2"
" being used is not compatible with the libxml2"
" header files that PostgreSQL was built with.")));
* Also, install an entity loader to prevent unwanted fetches of external
* files and URLs.
*/
errcxt->saved_entityfunc = xmlGetExternalEntityLoader();
xmlSetExternalEntityLoader(xmlPgEntityLoader);
return errcxt;
}
* pg_xml_done --- restore previous libxml error handling
*
* Resets libxml's global error-handling state to what it was before
* pg_xml_init() was called.
*
* This routine verifies that all pending errors have been dealt with
* (in assert-enabled builds, anyway).
*/
void pg_xml_done(PgXmlErrorContext* errcxt, bool isError)
{
void* cur_errcxt = NULL;
Assert(errcxt->magic == ERRCXT_MAGIC);
* In a normal exit, there should be no un-handled libxml errors. But we
* shouldn't try to enforce this during error recovery, since the longjmp
* could have been thrown before xml_ereport had a chance to run.
*/
Assert(!errcxt->err_occurred || isError);
* Check that libxml's global state is correct, warn if not. This is a
* real test and not an Assert because it has a higher probability of
* happening.
*/
#ifdef HAVE_XMLSTRUCTUREDERRORCONTEXT
cur_errcxt = xmlStructuredErrorContext;
#else
cur_errcxt = xmlGenericErrorContext;
#endif
if (cur_errcxt != (void*)errcxt)
elog(WARNING, "libxml error handling state is out of sync with xml.c");
xmlSetStructuredErrorFunc(errcxt->saved_errcxt, errcxt->saved_errfunc);
xmlSetExternalEntityLoader(errcxt->saved_entityfunc);
* Mark the struct as invalid, just in case somebody somehow manages to
* call xml_errorHandler or xml_ereport with it.
*/
errcxt->magic = 0;
pfree_ext(errcxt->err_buf.data);
pfree_ext(errcxt);
}
* pg_xml_error_occurred() --- test the error flag
*/
bool pg_xml_error_occurred(PgXmlErrorContext* errcxt)
{
return errcxt->err_occurred;
}
* SQL/XML allows storing "XML documents" or "XML content". "XML
* documents" are specified by the XML specification and are parsed
* easily by libxml. "XML content" is specified by SQL/XML as the
* production "XMLDecl? content". But libxml can only parse the
* "content" part, so we have to parse the XML declaration ourselves
* to complete this.
*/
#define SKIP_XML_SPACE(p) \
while (xmlIsBlank_ch(*(p))) \
(p)++
#define PG_XMLISNAMECHAR(c) \
(xmlIsBaseChar_ch(c) || xmlIsIdeographicQ(c) || xmlIsDigit_ch(c) || c == '.' || c == '-' || c == '_' || \
c == ':' || xmlIsCombiningQ(c) || xmlIsExtender_ch(c))
static xmlChar* xml_pnstrdup(const xmlChar* str, size_t len)
{
xmlChar* result = NULL;
result = (xmlChar*)palloc((len + 1) * sizeof(xmlChar));
errno_t rc = memcpy_s(result, (len + 1) * sizeof(xmlChar), str, len * sizeof(xmlChar));
securec_check(rc, "\0", "\0");
result[len] = 0;
return result;
}
static xmlChar* xml_charpnstrdup(char* str, size_t len)
{
xmlChar* result = NULL;
result = (xmlChar*)palloc((len + 1) * sizeof(xmlChar));
errno_t rc = memcpy_s(result, (len + 1) * sizeof(xmlChar), str, len);
securec_check(rc, "\0", "\0");
result[len] = 0;
return result;
}
* str is the null-terminated input string. Remaining arguments are
* output arguments; each can be NULL if value is not wanted.
* version and encoding are returned as locally-palloc'd strings.
* Result is 0 if OK, an error code if not.
*/
static int parse_xml_decl(const xmlChar* str, size_t* lenp, xmlChar** version, xmlChar** encoding, int* standalone)
{
const xmlChar* p = NULL;
const xmlChar* save_p = NULL;
size_t len;
int utf8char;
int utf8len;
* Only initialize libxml. We don't need error handling here, but we do
* need to make sure libxml is initialized before calling any of its
* functions. Note that this is safe (and a no-op) if caller has already
* done pg_xml_init().
*/
pg_xml_init_library();
if (version != NULL)
*version = NULL;
if (encoding != NULL)
*encoding = NULL;
if (standalone != NULL)
*standalone = -1;
p = str;
if (xmlStrncmp(p, (xmlChar*)"<?xml", 5) != 0)
goto finished;
utf8len = strlen((const char*)(p + 5));
utf8char = xmlGetUTF8Char(p + 5, &utf8len);
if (PG_XMLISNAMECHAR(utf8char))
goto finished;
p += 5;
if (!xmlIsBlank_ch(*(p)))
return XML_ERR_SPACE_REQUIRED;
SKIP_XML_SPACE(p);
if (xmlStrncmp(p, (xmlChar*)"version", 7) != 0)
return XML_ERR_VERSION_MISSING;
p += 7;
SKIP_XML_SPACE(p);
if (*p != '=')
return XML_ERR_VERSION_MISSING;
p += 1;
SKIP_XML_SPACE(p);
if (*p == '\'' || *p == '"') {
const xmlChar* q = NULL;
q = xmlStrchr(p + 1, *p);
if (q == NULL)
return XML_ERR_VERSION_MISSING;
if (version != NULL)
*version = xml_pnstrdup(p + 1, q - p - 1);
p = q + 1;
} else
return XML_ERR_VERSION_MISSING;
save_p = p;
SKIP_XML_SPACE(p);
if (xmlStrncmp(p, (xmlChar*)"encoding", 8) == 0) {
if (!xmlIsBlank_ch(*(save_p)))
return XML_ERR_SPACE_REQUIRED;
p += 8;
SKIP_XML_SPACE(p);
if (*p != '=')
return XML_ERR_MISSING_ENCODING;
p += 1;
SKIP_XML_SPACE(p);
if (*p == '\'' || *p == '"') {
const xmlChar* q = NULL;
q = xmlStrchr(p + 1, *p);
if (q == NULL)
return XML_ERR_MISSING_ENCODING;
if (encoding != NULL)
*encoding = xml_pnstrdup(p + 1, q - p - 1);
p = q + 1;
} else
return XML_ERR_MISSING_ENCODING;
} else {
p = save_p;
}
save_p = p;
SKIP_XML_SPACE(p);
if (xmlStrncmp(p, (xmlChar*)"standalone", 10) == 0) {
if (!xmlIsBlank_ch(*(save_p)))
return XML_ERR_SPACE_REQUIRED;
p += 10;
SKIP_XML_SPACE(p);
if (*p != '=')
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 (standalone != NULL)
*standalone = 1;
p += 5;
} else if (xmlStrncmp(p, (xmlChar*)"'no'", 4) == 0 || xmlStrncmp(p, (xmlChar*)"\"no\"", 4) == 0) {
if (standalone != NULL)
*standalone = 0;
p += 4;
} else
return XML_ERR_STANDALONE_VALUE;
} else {
p = save_p;
}
SKIP_XML_SPACE(p);
if (xmlStrncmp(p, (xmlChar*)"?>", 2) != 0)
return XML_ERR_XMLDECL_NOT_FINISHED;
p += 2;
finished:
len = p - str;
for (p = str; p < str + len; p++)
if (*p > 127)
return XML_ERR_INVALID_CHAR;
if (lenp != NULL)
*lenp = len;
return XML_ERR_OK;
}
* Write an XML declaration. On output, we adjust the XML declaration
* 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
* so that you don't get trivial things like xml '<foo/>' resulting in
* '<?xml version="1.0"?><foo/>', which would surely be annoying. We
* must provide a declaration if the standalone property is specified
* or if we include an encoding declaration. If we have a
* declaration, we must specify a version (XML requires this).
* Otherwise we only make a declaration if the version is not "1.0",
* which is the default version specified in SQL:2003.
*/
static bool print_xml_decl(StringInfo buf, const xmlChar* version, pg_enc encoding, int standalone)
{
if ((version && strcmp((const char*)version, PG_XML_DEFAULT_VERSION) != 0) || (encoding && encoding != PG_UTF8) ||
standalone != -1) {
appendStringInfoString(buf, "<?xml");
if (version != NULL)
appendStringInfo(buf, " version=\"%s\"", version);
else
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));
}
if (standalone == 1)
appendStringInfoString(buf, " standalone=\"yes\"");
else if (standalone == 0)
appendStringInfoString(buf, " standalone=\"no\"");
appendStringInfoString(buf, "?>");
return true;
} else
return false;
}
static xmlDocPtr try_xml_parse_on_document_mode(text* data, bool preserve_whitespace, int encoding)
{
volatile xmlDocPtr doc = NULL;
bool is_error_on_document = false;
PG_TRY();
{
doc = xml_parse(data, XMLOPTION_DOCUMENT, preserve_whitespace, encoding, false);
}
PG_CATCH();
{
is_error_on_document = true;
FlushErrorState();
}
PG_END_TRY();
if (doc != NULL && !is_error_on_document) {
return doc;
}
if (doc != NULL)
xmlFreeDoc(doc);
return NULL;
}
* Convert a C string to XML internal representation
*
* Note: it is caller's responsibility to xmlFreeDoc() the result,
* else a permanent memory leak will ensue!
*
* Maybe libxml2's xmlreader is better? (do not construct DOM,
* yet do not use SAX - see xmlreader.c)
*/
static xmlDocPtr xml_parse(text* data, XmlOptionType xmloption_arg, bool preserve_whitespace, int encoding,
bool can_ignore, bool try_another_parse_mode)
{
int32 len;
xmlChar* string = NULL;
xmlChar* utf8string = NULL;
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlParserCtxtPtr ctxt = NULL;
volatile xmlDocPtr doc = NULL;
volatile bool ignore_fail = false;
len = VARSIZE(data) - VARHDRSZ;
string = xml_text2xmlChar(data);
utf8string = pg_do_encoding_conversion(string, len, encoding, PG_UTF8);
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_WELLFORMED);
PG_TRY();
{
xmlInitParser();
ctxt = xmlNewParserCtxt();
if (ctxt == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate parser context");
if (xmloption_arg == XMLOPTION_DOCUMENT) {
* Note, that here we try to apply DTD defaults
* (XML_PARSE_DTDATTR) according to SQL/XML:2008 GR 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:2008 GR
* 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 || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, can_ignore ? WARNING : ERROR, ERRCODE_INVALID_XML_DOCUMENT,
"invalid XML document");
ignore_fail = true;
goto ignorable_error_handle;
}
} else {
int res_code;
size_t count;
xmlChar* version = NULL;
int standalone;
res_code = parse_xml_decl(utf8string, &count, &version, NULL, &standalone);
if (res_code != 0) {
if (can_ignore) {
xml_ereport(xmlerrcxt, WARNING, ERRCODE_INVALID_XML_DOCUMENT, "invalid XML document");
ignore_fail = true;
goto ignorable_error_handle;
} else {
xml_ereport_by_code(ERROR, ERRCODE_INVALID_XML_CONTENT,
"invalid XML content: invalid XML declaration", res_code);
}
}
doc = xmlNewDoc(version);
Assert(doc->encoding == NULL);
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) {
* we will try to use use XMLOPTION_DOCUMENT to parse again when we use XMLOPTION_CONTENT failed
*/
if (try_another_parse_mode) {
if (doc != NULL) {
xmlFreeDoc(doc);
doc = NULL;
}
doc = try_xml_parse_on_document_mode(data, preserve_whitespace, encoding);
if (doc != NULL) {
xmlFreeParserCtxt(ctxt);
pg_xml_done(xmlerrcxt, true);
return doc;
}
}
xml_ereport(xmlerrcxt, can_ignore ? WARNING : ERROR, ERRCODE_INVALID_XML_CONTENT,
"invalid XML content");
ignore_fail = true;
goto ignorable_error_handle;
}
}
ignorable_error_handle:
;
}
PG_CATCH();
{
if (doc != NULL)
xmlFreeDoc(doc);
if (ctxt != NULL)
xmlFreeParserCtxt(ctxt);
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
if (ignore_fail) {
if (doc != NULL)
xmlFreeDoc(doc);
text *new_data = cstring_to_text("null");
xmlChar *new_utf8string = pg_do_encoding_conversion(xml_text2xmlChar(new_data),
VARSIZE(new_data) - VARHDRSZ, encoding, PG_UTF8);
doc = xmlCtxtReadDoc(
ctxt, new_utf8string, NULL, "UTF-8",
XML_PARSE_NOENT | XML_PARSE_DTDATTR | (preserve_whitespace ? 0 : XML_PARSE_NOBLANKS));
}
xmlFreeParserCtxt(ctxt);
pg_xml_done(xmlerrcxt, ignore_fail);
return doc;
}
* xmlChar<->text conversions
*/
static xmlChar* xml_text2xmlChar(text* in)
{
return (xmlChar*)text_to_cstring(in);
}
#ifdef USE_LIBXMLCONTEXT
* Manage the special context used for all libxml allocations (but only
* in special debug builds; see notes at top of file)
*/
static void xml_memory_init(void)
{
if (LibxmlContext == NULL)
LibxmlContext = AllocSetContextCreate(t_thrd.top_mem_cxt,
"LibxmlContext",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
xmlMemSetup(xml_pfree, xml_palloc, xml_repalloc, xml_pstrdup);
}
* Wrappers for memory management functions
*/
static void* xml_palloc(size_t size)
{
return MemoryContextAlloc(LibxmlContext, size);
}
static void* xml_repalloc(void* ptr, size_t size)
{
return repalloc(ptr, size);
}
static void xml_pfree_ext(void* ptr)
{
if (ptr != NULL)
pfree_ext(ptr);
}
static char* xml_pstrdup(const char* string)
{
return MemoryContextStrdup(LibxmlContext, string);
}
#endif
* xmlPgEntityLoader --- entity loader callback function
*
* Silently prevent any external entity URL from being loaded. We don't want
* to throw an error, so instead make the entity appear to expand to an empty
* string.
*
* We would prefer to allow loading entities that exist in the system's
* global XML catalog; but the available libxml2 APIs make that a complex
* and fragile task. For now, just shut down all external access.
*/
static xmlParserInputPtr xmlPgEntityLoader(const char* URL, const char* ID, xmlParserCtxtPtr ctxt)
{
return xmlNewStringInputStream(ctxt, (const xmlChar*)"");
}
* xml_ereport --- report an XML-related error
*
* The "msg" is the SQL-level message; some can be adopted from the SQL/XML
* standard. This function adds libxml's native error message, if any, as
* detail.
*
* This is exported for modules that want to share the core libxml error
* handler. Note that pg_xml_init() *must* have been called previously.
*/
void xml_ereport(PgXmlErrorContext* errcxt, int level, int sqlcode, const char* msg)
{
char* detail = NULL;
if (errcxt->magic != ERRCXT_MAGIC)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_INVALID_XML_ERROR_CONTEXT),
errmsg("xml_ereport called with invalid PgXmlErrorContext"))));
errcxt->err_occurred = false;
if (errcxt->err_buf.len > 0)
detail = errcxt->err_buf.data;
else
detail = NULL;
ereport(level, (errcode(sqlcode), errmsg_internal("%s", msg), detail ? errdetail_internal("%s", detail) : 0));
}
static void xml_append_errbuf(xmlErrorPtr error, const xmlChar* name, StringInfo errorBuf)
{
if (error->line > 0)
appendStringInfo(errorBuf, "line %d: ", error->line);
if (name != NULL)
appendStringInfo(errorBuf, "element %s: ", name);
if (error->message != NULL)
appendStringInfoString(errorBuf, error->message);
else
appendStringInfoString(errorBuf, "(no message provided)");
return;
}
* Error handler for libxml errors and warnings
*/
static void xml_error_handler(void* data, xmlErrorPtr error)
{
PgXmlErrorContext* xmlerrcxt = (PgXmlErrorContext*)data;
xmlParserCtxtPtr ctxt = (xmlParserCtxtPtr)error->ctxt;
xmlParserInputPtr input = (ctxt != NULL) ? ctxt->input : NULL;
xmlNodePtr node = (xmlNodePtr)error->node;
const xmlChar* name = (node != NULL && node->type == XML_ELEMENT_NODE) ? node->name : NULL;
int domain = error->domain;
int level = error->level;
StringInfo errorBuf;
* Defend against someone passing us a bogus context struct.
*
* We force a backend exit if this check fails because longjmp'ing out of
* libxml would likely render it unsafe to use further.
*/
if (xmlerrcxt->magic != ERRCXT_MAGIC) {
ereport(FATAL,
(errmodule(MOD_OPT),
(errcode(ERRCODE_INVALID_XML_ERROR_CONTEXT),
errmsg("xml_errorHandler called with invalid PgXmlErrorContext"))));
}
* Older libxml versions report some errors differently.
* First, some errors were previously reported as coming from the parser
* domain but are now reported as coming from the namespace domain.
* Second, some warnings were upgraded to errors.
* We attempt to compensate for that here.
* ----------
*/
switch (error->code) {
case XML_WAR_NS_URI:
level = XML_ERR_ERROR;
domain = XML_FROM_NAMESPACE;
break;
case XML_ERR_NS_DECL_ERROR:
case XML_WAR_NS_URI_RELATIVE:
case XML_WAR_NS_COLUMN:
case XML_NS_ERR_XML_NAMESPACE:
case XML_NS_ERR_UNDEFINED_NAMESPACE:
case XML_NS_ERR_QNAME:
case XML_NS_ERR_ATTRIBUTE_REDEFINED:
case XML_NS_ERR_EMPTY:
domain = XML_FROM_NAMESPACE;
break;
default:
break;
}
switch (domain) {
case XML_FROM_PARSER:
case XML_FROM_NONE:
case XML_FROM_MEMORY:
case XML_FROM_IO:
* Suppress warnings about undeclared entities. We need to do
* this to avoid problems due to not loading DTD definitions.
*/
if (error->code == XML_WAR_UNDECLARED_ENTITY)
return;
break;
default:
if (xmlerrcxt->strictness == PG_XML_STRICTNESS_WELLFORMED)
return;
break;
}
errorBuf = makeStringInfo();
xml_append_errbuf(error, name, errorBuf);
* Append context information to errorBuf.
*
* xmlParserPrintFileContext() uses libxml's "generic" error handler to
* write the context. Since we don't want to duplicate libxml
* functionality here, we set up a generic error handler temporarily.
*
* We use appendStringInfo() directly as libxml's generic error handler.
* This should work because it has essentially the same signature as
* libxml expects, namely (void *ptr, const char *msg, ...).
*/
if (input != NULL) {
xmlGenericErrorFunc errFuncSaved = xmlGenericError;
void* errCtxSaved = xmlGenericErrorContext;
xmlSetGenericErrorFunc((void*)errorBuf, (xmlGenericErrorFunc)appendStringInfo);
appendStringInfoLineSeparator(errorBuf);
xmlParserPrintFileContext(input);
xmlSetGenericErrorFunc(errCtxSaved, errFuncSaved);
}
chopStringInfoNewlines(errorBuf);
* Legacy error handling mode. err_occurred is never set, we just add the
* message to err_buf. This mode exists because the xml2 contrib module
* uses our error-handling infrastructure, but we don't want to change its
* behaviour since it's deprecated anyway. This is also why we don't
* distinguish between notices, warnings and errors here --- the old-style
* generic error handler wouldn't have done that either.
*/
if (xmlerrcxt->strictness == PG_XML_STRICTNESS_LEGACY) {
appendStringInfoLineSeparator(&xmlerrcxt->err_buf);
appendStringInfoString(&xmlerrcxt->err_buf, errorBuf->data);
pfree_ext(errorBuf->data);
pfree_ext(errorBuf);
return;
}
* We don't want to ereport() here because that'd probably leave libxml in
* an inconsistent state. Instead, we remember the error and ereport()
* from xml_ereport().
*
* Warnings and notices can be reported immediately since they won't cause
* a longjmp() out of libxml.
*/
if (level >= XML_ERR_ERROR) {
appendStringInfoLineSeparator(&xmlerrcxt->err_buf);
appendStringInfoString(&xmlerrcxt->err_buf, errorBuf->data);
xmlerrcxt->err_occurred = true;
} else if (level >= XML_ERR_WARNING) {
ereport(WARNING, (errmsg_internal("%s", errorBuf->data)));
} else {
ereport(NOTICE, (errmsg_internal("%s", errorBuf->data)));
}
pfree_ext(errorBuf->data);
pfree_ext(errorBuf);
}
* Wrapper for "ereport" function for XML-related errors. The "msg"
* is the SQL-level message; some can be adopted from the SQL/XML
* standard. This function uses "code" to create a textual detail
* message. At the moment, we only need to cover those codes that we
* may raise in this file.
*/
static void xml_ereport_by_code(int level, int sqlcode, const char* msg, int code)
{
const char* det = NULL;
switch (code) {
case XML_ERR_INVALID_CHAR:
det = gettext_noop("Invalid character value.");
break;
case XML_ERR_SPACE_REQUIRED:
det = gettext_noop("Space required.");
break;
case XML_ERR_STANDALONE_VALUE:
det = gettext_noop("standalone accepts only 'yes' or 'no'.");
break;
case XML_ERR_VERSION_MISSING:
det = gettext_noop("Malformed declaration: missing version.");
break;
case XML_ERR_MISSING_ENCODING:
det = gettext_noop("Missing encoding in text declaration.");
break;
case XML_ERR_XMLDECL_NOT_FINISHED:
det = gettext_noop("Parsing XML declaration: '?>' expected.");
break;
default:
det = gettext_noop("Unrecognized libxml error code: %d.");
break;
}
ereport(level, (errcode(sqlcode), errmsg_internal("%s", msg), errdetail(det, code)));
}
* Remove all trailing newlines from a StringInfo string
*/
static void chopStringInfoNewlines(StringInfo str)
{
while (str->len > 0 && str->data[str->len - 1] == '\n')
str->data[--str->len] = '\0';
}
* Append a newline after removing any existing trailing newlines
*/
static void appendStringInfoLineSeparator(StringInfo str)
{
chopStringInfoNewlines(str);
if (str->len > 0)
appendStringInfoChar(str, '\n');
}
* Convert one char in the current server encoding to a Unicode codepoint.
*/
static pg_wchar sqlchar_to_unicode(char* s)
{
char* utf8string = NULL;
pg_wchar ret[2];
utf8string = (char*)pg_do_encoding_conversion((unsigned char*)s, pg_mblen(s), GetDatabaseEncoding(), PG_UTF8);
pg_encoding_mb2wchar_with_len(PG_UTF8, utf8string, ret, pg_encoding_mblen(PG_UTF8, utf8string));
if (utf8string != s)
pfree_ext(utf8string);
return ret[0];
}
static bool is_valid_xml_namefirst(pg_wchar c)
{
return (xmlIsBaseCharQ(c) || xmlIsIdeographicQ(c) || c == '_' || c == ':');
}
static bool is_valid_xml_namechar(pg_wchar c)
{
return (xmlIsBaseCharQ(c) || xmlIsIdeographicQ(c) || xmlIsDigitQ(c) || c == '.' || c == '-' || c == '_' ||
c == ':' || xmlIsCombiningQ(c) || xmlIsExtenderQ(c));
}
#endif
* Map SQL identifier to XML name; see SQL/XML:2008 section 9.1.
*/
char* map_sql_identifier_to_xml_name(char* ident, bool fully_escaped, bool escape_period)
{
#ifdef USE_LIBXML
StringInfoData buf;
char* p = NULL;
* SQL/XML doesn't make use of this case anywhere, so it's probably a
* mistake.
*/
Assert(fully_escaped || !escape_period);
initStringInfo(&buf);
for (p = ident; *p; p += pg_mblen(p)) {
if (*p == ':' && (p == ident || fully_escaped))
appendStringInfo(&buf, "_x003A_");
else if (*p == '_' && *(p + 1) == 'x')
appendStringInfo(&buf, "_x005F_");
else if (fully_escaped && p == ident && pg_strncasecmp(p, "xml", 3) == 0) {
if (*p == 'x')
appendStringInfo(&buf, "_x0078_");
else
appendStringInfo(&buf, "_x0058_");
} else if (escape_period && *p == '.')
appendStringInfo(&buf, "_x002E_");
else {
pg_wchar u = sqlchar_to_unicode(p);
if ((p == ident) ? !is_valid_xml_namefirst(u) : !is_valid_xml_namechar(u))
appendStringInfo(&buf, "_x%04X_", (unsigned int)u);
else
appendBinaryStringInfo(&buf, p, pg_mblen(p));
}
}
return buf.data;
#else
NO_XML_SUPPORT();
return NULL;
#endif
}
* Map a Unicode codepoint into the current server encoding.
*/
static char* unicode_to_sqlchar(pg_wchar c)
{
unsigned char utf8string[5];
char* result = NULL;
errno_t rc = 0;
rc = memset_s(utf8string, sizeof(utf8string), 0, sizeof(utf8string));
securec_check(rc, "\0", "\0");
unicode_to_utf8(c, utf8string);
result = (char*)pg_do_encoding_conversion(
utf8string, pg_encoding_mblen(PG_UTF8, (char*)utf8string), PG_UTF8, GetDatabaseEncoding());
if (result == (char*)utf8string)
result = pstrdup(result);
return result;
}
* Map XML name to SQL identifier; see SQL/XML:2008 section 9.3.
*/
char* map_xml_name_to_sql_identifier(char* name)
{
StringInfoData buf;
char* p = NULL;
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) == '_') {
unsigned int u;
errno_t ss_rc = sscanf_s(p + 2, "%X", &u);
securec_check_for_sscanf_s(ss_rc, 1, "\0", "\0");
appendStringInfoString(&buf, unicode_to_sqlchar(u));
p += 6;
} else
appendBinaryStringInfo(&buf, p, pg_mblen(p));
}
return buf.data;
}
* Map SQL value to XML value; see SQL/XML:2008 section 9.8.
*
* When xml_escape_strings is true, then certain characters in string
* values are replaced by entity references (< etc.), as specified
* in SQL/XML:2008 section 9.8 GR 9) a) iii). This is normally what is
* wanted. The false case is mainly useful when the resulting value
* is used with xmlTextWriterWriteAttribute() to write out an
* attribute, because that function does the escaping itself.
*/
char* map_sql_value_to_xml_value(Datum value, Oid type, bool xml_escape_strings)
{
if (type_is_array_domain(type)) {
ArrayType* array = NULL;
Oid elmtype;
int16 elmlen;
bool elmbyval = false;
char elmalign;
int num_elems;
Datum* elem_values = NULL;
bool* elem_nulls = NULL;
StringInfoData buf;
int i;
array = DatumGetArrayTypeP(value);
elmtype = ARR_ELEMTYPE(array);
get_typlenbyvalalign(elmtype, &elmlen, &elmbyval, &elmalign);
deconstruct_array(array, elmtype, elmlen, elmbyval, elmalign, &elem_values, &elem_nulls, &num_elems);
initStringInfo(&buf);
for (i = 0; i < num_elems; i++) {
if (elem_nulls[i])
continue;
appendStringInfoString(&buf, "<element>");
appendStringInfoString(&buf, map_sql_value_to_xml_value(elem_values[i], elmtype, true));
appendStringInfoString(&buf, "</element>");
}
pfree_ext(elem_values);
pfree_ext(elem_nulls);
return buf.data;
} else {
Oid typeOut;
bool isvarlena = false;
char* str = NULL;
* 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);
if (DATE_NOT_FINITE(date))
ereport(ERROR,
(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
errmsg("date out of range"),
errdetail("XML does not support infinite date values.")));
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 buf[MAXDATELEN + 1];
timestamp = DatumGetTimestamp(value);
if (TIMESTAMP_NOT_FINITE(timestamp))
ereport(ERROR,
(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
errmsg("timestamp out of range"),
errdetail("XML does not support infinite timestamp values.")));
else if (timestamp2tm(timestamp, NULL, &tm, &fsec, NULL, NULL) == 0)
EncodeDateTime(&tm, fsec, false, 0, NULL, 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;
const char* tzn = NULL;
char buf[MAXDATELEN + 1];
timestamp = DatumGetTimestamp(value);
if (TIMESTAMP_NOT_FINITE(timestamp))
ereport(ERROR,
(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
errmsg("timestamp out of range"),
errdetail("XML does not support infinite timestamp values.")));
else if (timestamp2tm(timestamp, &tz, &tm, &fsec, &tzn, NULL) == 0)
EncodeDateTime(&tm, fsec, true, tz, tzn, USE_XSD_DATES, buf);
else
ereport(ERROR, (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), errmsg("timestamp out of range")));
return pstrdup(buf);
}
#ifdef USE_LIBXML
case BYTEAOID: {
bytea* bstr = DatumGetByteaPP(value);
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlBufferPtr buf = NULL;
volatile xmlTextWriterPtr writer = NULL;
char* result = NULL;
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
buf = xmlBufferCreate();
if (buf == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlBuffer");
writer = xmlNewTextWriterMemory(buf, 0);
if (writer == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate xmlTextWriter");
if (u_sess->attr.attr_common.xmlbinary == XMLBINARY_BASE64)
xmlTextWriterWriteBase64(writer, VARDATA_ANY(bstr), 0, VARSIZE_ANY_EXHDR(bstr));
else
xmlTextWriterWriteBinHex(writer, VARDATA_ANY(bstr), 0, VARSIZE_ANY_EXHDR(bstr));
xmlFreeTextWriter(writer);
writer = NULL;
result = pstrdup((const char*)xmlBufferContent(buf));
}
PG_CATCH();
{
if (writer)
xmlFreeTextWriter(writer);
if (buf)
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlBufferFree(buf);
pg_xml_done(xmlerrcxt, false);
return result;
}
#endif
default:
break;
}
* otherwise, just use the type's native text representation
*/
getTypeOutputInfo(type, &typeOut, &isvarlena);
str = OidOutputFunctionCall(typeOut, value);
if (type == XMLOID || !xml_escape_strings)
return str;
return escape_xml(str);
}
}
* Escape characters in text that have special meanings in XML.
*
* Returns a palloc'd string.
*
* NB: this is intentionally not dependent on libxml.
*/
char* escape_xml(const char* str)
{
StringInfoData buf;
const char* p = NULL;
int charlen = 0;
initStringInfo(&buf);
p = str;
while (*p) {
charlen = pg_mblen(p);
switch (*p) {
case '&':
appendStringInfoString(&buf, "&");
break;
case '<':
appendStringInfoString(&buf, "<");
break;
case '>':
appendStringInfoString(&buf, ">");
break;
case '\r':
appendStringInfoString(&buf, "
");
break;
default: {
for (int i = 0; i < charlen; i++)
appendStringInfoCharMacro(&buf, p[i]);
break;
}
}
p += charlen;
}
return buf.data;
}
static char* _SPI_strdup(const char* s)
{
size_t len = strlen(s) + 1;
char* ret = (char*)SPI_palloc(len);
errno_t rc = memcpy_s(ret, len, s, len);
securec_check(rc, "\0", "\0");
return ret;
}
* SQL to XML mapping functions
*
* What follows below was at one point intentionally organized so that
* you can read along in the SQL/XML standard. The functions are
* mostly split up the way the clauses lay out in the standards
* document, and the identifiers are also aligned with the standard
* text. Unfortunately, SQL/XML:2006 reordered the clauses
* differently than SQL/XML:2003, so the order below doesn't make much
* sense anymore.
*
* 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:2008 section
* 4.10.8.
*/
* 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 < (int)SPI_processed; i++) {
Datum oid;
bool isnull = false;
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', 'm') 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)
{
return query_to_oid_list(
"SELECT oid FROM pg_catalog.pg_class WHERE relkind IN ('r', 'v', 'm') 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:2008
* section 9.11.
*/
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)
{
NO_XML_SUPPORT();
Oid relid = PG_GETARG_OID(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
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)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
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 = NULL;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
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)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
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 = NULL;
StringInfoData result;
Portal portal;
int i;
int rc = 0;
if (PG_ARGISNULL(4))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(4));
initStringInfo(&result);
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
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 < (int)SPI_processed; i++)
SPI_sql_row_to_xmlelement(i, &result, NULL, nulls, tableforest, targetns, true);
SPI_STACK_LOG("finish", portal->sourceText, NULL);
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)
{
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 != NULL) {
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 = NULL;
int i;
int rc = 0;
if (tablename != NULL)
xmltn = map_sql_identifier_to_xml_name(tablename, true, false);
else
xmltn = "table";
result = makeStringInfo();
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
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 != NULL)
appendStringInfo(result, "%s\n\n", xmlschema);
for (i = 0; i < (int)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_STACK_LOG("finish", query, NULL);
SPI_finish();
return result;
}
Datum table_to_xmlschema(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
Oid relid = PG_GETARG_OID(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
const char* result = NULL;
Relation rel;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
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)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
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 = NULL;
const char* result = NULL;
SPIPlanPtr plan;
Portal portal;
int rc = 0;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
if ((plan = SPI_prepare(query, 0, NULL)) == NULL)
ereport(ERROR,
(errmodule(MOD_OPT), (errcode(ERRCODE_SPI_PREPARE_FAILURE), errmsg("SPI_prepare(\"%s\") failed", query))));
if ((portal = SPI_cursor_open(NULL, plan, NULL, NULL, true)) == NULL)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CURSOR_OPEN_FAILURE), errmsg("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_STACK_LOG("finish", portal->sourceText, NULL);
SPI_finish();
PG_RETURN_XML_P(cstring_to_xmltype(result));
}
Datum cursor_to_xmlschema(PG_FUNCTION_ARGS)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
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 = NULL;
const char* xmlschema = NULL;
Portal portal;
int rc = 0;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
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_STACK_LOG("finish", portal->sourceText, NULL);
SPI_finish();
PG_RETURN_XML_P(cstring_to_xmltype(xmlschema));
}
Datum table_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
Oid relid = PG_GETARG_OID(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
Relation rel;
const char* xmlschema = NULL;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
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)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
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 = NULL;
const char* xmlschema = NULL;
SPIPlanPtr plan;
Portal portal;
int rc = 0;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
if ((plan = SPI_prepare(query, 0, NULL)) == NULL)
ereport(ERROR,
(errmodule(MOD_OPT), (errcode(ERRCODE_SPI_PREPARE_FAILURE), errmsg("SPI_prepare(\"%s\") failed", query))));
if ((portal = SPI_cursor_open(NULL, plan, NULL, NULL, true)) == NULL)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CURSOR_OPEN_FAILURE), errmsg("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_STACK_LOG("finish", portal->sourceText, NULL);
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:2008
* sections 9.13, 9.14.
*/
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 = NULL;
List* relid_list = NIL;
ListCell* cell = NULL;
int rc = 0;
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 != NULL)
appendStringInfo(result, "%s\n\n", xmlschema);
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
relid_list = schema_get_xml_visible_tables(nspid);
SPI_STACK_LOG("push", NULL, NULL);
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_STACK_LOG("pop", NULL, NULL);
SPI_pop();
SPI_STACK_LOG("finish", NULL, NULL);
SPI_finish();
xmldata_root_element_end(result, xmlsn);
return result;
}
Datum schema_to_xml(PG_FUNCTION_ARGS)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
Name name = PG_GETARG_NAME(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
char* schemaname = NULL;
Oid nspid;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
schemaname = NameStr(*name);
if (schemaname == NULL) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("schema name is NULL.")));
}
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 = NIL;
List* tupdesc_list = NIL;
ListCell* cell = NULL;
StringInfo result;
int rc = 0;
result = makeStringInfo();
if (schemaname == NULL) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("schema name is NULL.")));
}
nspid = LookupExplicitNamespace(schemaname);
xsd_schema_element_start(result, targetns);
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
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_STACK_LOG("finish", NULL, NULL);
SPI_finish();
return result;
}
Datum schema_to_xmlschema(PG_FUNCTION_ARGS)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
Name name = PG_GETARG_NAME(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
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)
{
* If you want to remove the macro, please fix the issue caused by
* NULL input of first param. Check input of text_to_cstring? or
* modify the code below? or set proisstrict in pg_proc?
*/
NO_XML_SUPPORT();
Name name = PG_GETARG_NAME(0);
bool nulls = PG_GETARG_BOOL(1);
bool tableforest = PG_GETARG_BOOL(2);
const char* targetns = NULL;
char* schemaname = NULL;
Oid nspid;
StringInfo xmlschema;
if (PG_ARGISNULL(3))
targetns = DEF_TARGETNS;
else
targetns = text_to_cstring(PG_GETARG_TEXT_PP(3));
schemaname = NameStr(*name);
if (schemaname == NULL) {
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("schema name is NULL.")));
}
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:2008
* sections 9.16, 9.17.
*/
static StringInfo database_to_xml_internal(const char* xmlschema, bool nulls, bool tableforest, const char* targetns)
{
StringInfo result;
List* nspid_list = NIL;
ListCell* cell = NULL;
char* xmlcn = NULL;
int rc = 0;
xmlcn = map_sql_identifier_to_xml_name(get_and_check_db_name(u_sess->proc_cxt.MyDatabaseId, true), true, false);
result = makeStringInfo();
xmldata_root_element_start(result, xmlcn, xmlschema, targetns, true);
if (xmlschema != NULL)
appendStringInfo(result, "%s\n\n", xmlschema);
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
nspid_list = database_get_xml_visible_schemas();
SPI_STACK_LOG("push", NULL, NULL);
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_STACK_LOG("pop", NULL, NULL);
SPI_pop();
SPI_STACK_LOG("finish", NULL, NULL);
SPI_finish();
xmldata_root_element_end(result, xmlcn);
return result;
}
Datum database_to_xml(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
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 = NIL;
List* nspid_list = NIL;
List* tupdesc_list = NIL;
ListCell* cell = NULL;
StringInfo result;
int rc = 0;
result = makeStringInfo();
xsd_schema_element_start(result, targetns);
* Connect to SPI manager
*/
SPI_STACK_LOG("connect", NULL, NULL);
if ((rc = SPI_connect()) != SPI_OK_CONNECT)
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_SPI_CONNECTION_FAILURE),
errmsg("SPI_connect failed: %s", SPI_result_code_string(rc)))));
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));
xsd_schema_element_end(result);
SPI_STACK_LOG("finish", NULL, NULL);
SPI_finish();
return result;
}
Datum database_to_xmlschema(PG_FUNCTION_ARGS)
{
NO_XML_SUPPORT();
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)
{
NO_XML_SUPPORT();
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:2008 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 != NULL)
appendStringInfo(&result, "%s", map_sql_identifier_to_xml_name(a, true, true));
if (b != NULL)
appendStringInfo(&result, ".%s", map_sql_identifier_to_xml_name(b, true, true));
if (c != NULL)
appendStringInfo(&result, ".%s", map_sql_identifier_to_xml_name(c, true, true));
if (d != NULL)
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:2008
* section 9.11.
*
* Map an SQL table to XML Schema data types; see SQL/XML:2008 section
* 9.9.
*/
static const char* map_sql_table_to_xmlschema(
TupleDesc tupdesc, Oid relid, bool nulls, bool tableforest, const char* targetns)
{
int i;
char* xmltn = NULL;
char* tabletypename = NULL;
char* rowtypename = NULL;
StringInfoData result;
initStringInfo(&result);
if (OidIsValid(relid)) {
HeapTuple tuple;
Form_pg_class reltuple;
tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
if (!HeapTupleIsValid(tuple)) {
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_CACHE_LOOKUP_FAILED), errmsg("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(u_sess->proc_cxt.MyDatabaseId),
get_namespace_name(reltuple->relnamespace),
NameStr(reltuple->relname));
rowtypename = map_multipart_sql_identifier_to_xml_name("RowType",
get_database_name(u_sess->proc_cxt.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++) {
if (tupdesc->attrs[i].attisdropped)
continue;
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:2008
* section 9.12.
*/
static const char* map_sql_schema_to_xmlschema_types(
Oid nspid, List* relid_list, bool nulls, bool tableforest, const char* targetns)
{
char* dbname = NULL;
char* nspname = NULL;
char* xmlsn = NULL;
char* schematypename = NULL;
StringInfoData result;
ListCell* cell = NULL;
dbname = get_database_name(u_sess->proc_cxt.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(
(char*)(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:2008
* section 9.15.
*/
static const char* map_sql_catalog_to_xmlschema_types(List* nspid_list)
{
char* dbname = NULL;
char* xmlcn = NULL;
char* catalogtypename = NULL;
StringInfoData result;
ListCell* cell = NULL;
dbname = get_database_name(u_sess->proc_cxt.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:2008 section 9.4.
*/
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",
((unsigned int)(typmod - VARHDRSZ) >> 16) & 0xffff,
(unsigned int)(typmod - VARHDRSZ) & 0xffff);
break;
case INT4OID:
appendStringInfo(&result, "INTEGER");
break;
case INT2OID:
appendStringInfo(&result, "SMALLINT");
break;
case INT1OID:
appendStringInfo(&result, "TINYINT");
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 SMALLDATETIMEOID:
appendStringInfo(&result, "SMALLDATETIME");
break;
case DATEOID:
appendStringInfo(&result, "DATE");
break;
case XMLOID:
appendStringInfo(&result, "XML");
break;
default: {
HeapTuple tuple;
Form_pg_type typtuple;
tuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typeoid));
if (!HeapTupleIsValid(tuple)) {
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_CACHE_LOOKUP_FAILED), errmsg("cache lookup failed for type %u", typeoid))));
}
typtuple = (Form_pg_type)GETSTRUCT(tuple);
appendStringInfoString(&result,
map_multipart_sql_identifier_to_xml_name(
(char*)((typtuple->typtype == TYPTYPE_DOMAIN) ? "Domain" : "UDT"),
get_database_name(u_sess->proc_cxt.MyDatabaseId),
get_namespace_name(typtuple->typnamespace),
NameStr(typtuple->typname)));
ReleaseSysCache(tuple);
} break;
}
return result.data;
}
* Map a collection of SQL data types to XML Schema data types; see
* SQL/XML:2008 section 9.7.
*/
static const char* map_sql_typecoll_to_xmlschema_types(List* tupdesc_list)
{
List* uniquetypes = NIL;
int i;
StringInfoData result;
ListCell* cell0 = NULL;
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);
}
}
foreach (cell0, uniquetypes) {
Oid typid = lfirst_oid(cell0);
Oid basetypid = getBaseType(typid);
if (basetypid != typid)
uniquetypes = list_append_unique_oid(uniquetypes, basetypid);
}
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:2008 sections 9.5 and 9.6.
*
* (The distinction between 9.5 and 9.6 is basically that 9.6 adds
* a name attribute, which this function does. The name-less version
* 9.5 doesn't appear to be required anywhere.)
*/
static const char* map_sql_type_to_xmlschema_type(Oid typeoid, int typmod)
{
StringInfoData result;
const char* typname = 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", typname);
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",
(u_sess->attr.attr_common.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",
((unsigned int)(typmod - VARHDRSZ) >> 16) & 0xffff,
(short)((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:2008 section 9.10.
*/
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 = NULL;
if (tablename != NULL)
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 = NULL;
Datum colval;
bool isnull = false;
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), true),
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)
{
xmltype* result = NULL;
if (cur->type == XML_ELEMENT_NODE) {
xmlBufferPtr buf;
buf = xmlBufferCreate();
PG_TRY();
{
xmlNodeDump(buf, NULL, cur, 0, 1);
result = xmlBuffer_to_xmltype(buf);
}
PG_CATCH();
{
xmlBufferFree(buf);
PG_RE_THROW();
}
PG_END_TRY();
xmlBufferFree(buf);
} else {
xmlChar* str = NULL;
str = xmlXPathCastNodeToString(cur);
PG_TRY();
{
char* escaped = escape_xml((char*)str);
result = (xmltype*)cstring_to_text(escaped);
pfree_ext(escaped);
}
PG_CATCH();
{
xmlFree(str);
PG_RE_THROW();
}
PG_END_TRY();
xmlFree(str);
}
return result;
}
* Convert an XML XPath object (the result of evaluating an XPath expression)
* to an array of xml values, which is returned at *astate. The function
* result value is the number of elements in the array.
*
* If "astate" is NULL then we don't generate the array value, but we still
* return the number of elements it would have had.
*
* Nodesets are converted to an array containing the nodes' textual
* representations. Primitive values (float, double, string) are converted
* to a single-element array containing the value's string representation.
*/
static int xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj, ArrayBuildState** astate, PgXmlErrorContext *xmlerrcxt)
{
int result = 0;
Datum datum;
Oid datumtype;
char* result_str = NULL;
if (astate != NULL)
*astate = NULL;
switch (xpathobj->type) {
case XPATH_NODESET:
if (xpathobj->nodesetval != NULL) {
result = xpathobj->nodesetval->nodeNr;
if (astate != NULL) {
int i;
for (i = 0; i < result; i++) {
datum = PointerGetDatum(xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i]));
*astate = accumArrayResult(*astate, datum, false, XMLOID, CurrentMemoryContext);
}
}
}
return result;
case XPATH_BOOLEAN:
if (astate == NULL)
return 1;
datum = BoolGetDatum(xpathobj->boolval);
datumtype = BOOLOID;
break;
case XPATH_NUMBER:
if (astate == NULL)
return 1;
datum = Float8GetDatum(xpathobj->floatval);
datumtype = FLOAT8OID;
break;
case XPATH_STRING:
if (astate == NULL)
return 1;
datum = CStringGetDatum((char*)xpathobj->stringval);
datumtype = CSTRINGOID;
break;
default:
ereport(ERROR,
(errmodule(MOD_OPT),
(errcode(ERRCODE_CHECK_VIOLATION),
errmsg("xpath expression result type %d is unsupported", xpathobj->type))));
return 0;
}
result_str = map_sql_value_to_xml_value(datum, datumtype, true);
datum = PointerGetDatum(cstring_to_xmltype(result_str));
*astate = accumArrayResult(*astate, datum, false, XMLOID, CurrentMemoryContext);
return 1;
}
* Common code for xpath() and xmlexists()
*
* Evaluate XPath expression and return number of nodes in res_items
* and array of XML values in astate. Either of those pointers can be
* NULL if the corresponding result isn't wanted.
*
* It is up to the user to ensure that the XML passed is in fact
* an XML document - XPath doesn't work easily on fragments without
* a context node being known.
*/
static void xpath_internal(
text* xpath_expr_text, xmltype* data, ArrayType* namespaces, int* res_nitems, ArrayBuildState** astate)
{
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlParserCtxtPtr ctxt = NULL;
volatile xmlDocPtr doc = NULL;
volatile xmlXPathContextPtr xpathctx = NULL;
volatile xmlXPathCompExprPtr xpathcomp = NULL;
volatile xmlXPathObjectPtr xpathobj = NULL;
char* datastr = NULL;
int32 len;
int32 xpath_len;
xmlChar* string = NULL;
xmlChar* xpath_expr = NULL;
int i;
int ndim;
Datum* ns_names_uris = NULL;
bool* ns_names_uris_nulls = NULL;
int ns_count;
size_t xmldecl_len = 0;
* 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 = namespaces ? ARR_NDIM(namespaces) : 0;
if (ndim != 0) {
int* dims = NULL;
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);
ns_count /= 2;
} 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")));
string = xml_charpnstrdup(datastr, len);
xpath_expr = xml_charpnstrdup(VARDATA(xpath_expr_text), xpath_len);
if (GetDatabaseEncoding() == PG_UTF8) {
parse_xml_decl(string, &xmldecl_len, NULL, NULL, NULL);
}
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
xmlInitParser();
* redundant XML parsing (two parsings for the same value during one
* command execution are possible)
*/
ctxt = xmlNewParserCtxt();
if (ctxt == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate parser context");
doc = xmlCtxtReadMemory(ctxt, (char*)string + xmldecl_len, len - xmldecl_len, NULL, NULL, 0);
if (doc == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_XML_DOCUMENT, "could not parse XML document");
xpathctx = xmlXPathNewContext(doc);
if (xpathctx == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate XPath context");
xpathctx->node = xmlDocGetRootElement(doc);
if (xpathctx->node == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not find root XML element");
if (ns_count > 0) {
for (i = 0; i < ns_count; i++) {
char* ns_name = NULL;
char* ns_uri = NULL;
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,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg(
"could not register XML namespace with name \"%s\" and URI \"%s\"", ns_name, ns_uri)));
}
}
xpathcomp = xmlXPathCompile(xpath_expr);
if (xpathcomp == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_FILE, "invalid XPath expression");
* Version 2.6.27 introduces a function named
* xmlXPathCompiledEvalToBoolean, which would be enough for xmlexists,
* but we can derive the existence by whether any nodes are returned,
* thereby preventing a library version upgrade and keeping the code
* the same.
*/
xpathobj = xmlXPathCompiledEval(xpathcomp, xpathctx);
if (xpathobj == NULL || xmlerrcxt->err_occurred)
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNEXPECTED_NULL_VALUE, "could not create XPath object");
* Extract the results as requested.
*/
if (res_nitems != NULL)
*res_nitems = xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
else
(void)xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
}
PG_CATCH();
{
if (xpathobj)
xmlXPathFreeObject(xpathobj);
if (xpathcomp)
xmlXPathFreeCompExpr(xpathcomp);
if (xpathctx)
xmlXPathFreeContext(xpathctx);
if (doc)
xmlFreeDoc(doc);
if (ctxt)
xmlFreeParserCtxt(ctxt);
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlXPathFreeObject(xpathobj);
xmlXPathFreeCompExpr(xpathcomp);
xmlXPathFreeContext(xpathctx);
xmlFreeDoc(doc);
xmlFreeParserCtxt(ctxt);
pg_xml_done(xmlerrcxt, false);
}
static xmlChar* buildXpathAbsolutePath(text* xpath_expr_text)
{
xmlChar* xpath_expr = NULL;
int xpath_len = VARSIZE(xpath_expr_text) - VARHDRSZ;
if (xpath_len == 0)
ereport(ERROR, (errcode(ERRCODE_DATA_EXCEPTION), errmsg("empty XPath expression")));
xpath_expr = xml_charpnstrdup(VARDATA(xpath_expr_text), xpath_len);
return xpath_expr;
}
* Common code for xmltype_extract(), xmltype_xmlsequence() and xmltype_existsnode()
*
* Evaluate XPath expression and return number of nodes in res_items
* and array of XML values in astate. Either of those pointers can be
* NULL if the corresponding result isn't wanted.
*
* It is up to the user to ensure that the XML passed is in fact
* an XML document - XPath doesn't work easily on fragments without
* a context node being known.
*/
static void extract_internal(
xmltype* data, text* xpath_expr_text, ArrayType* namespaces, int* res_nitems, ArrayBuildState** astate)
{
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlDocPtr doc = NULL;
volatile xmlXPathContextPtr xpathctx = NULL;
volatile xmlXPathObjectPtr xpathobj = NULL;
xmlChar* xpath_expr = NULL;
int i = 0;
int ndim = 0;
Datum* ns_names_uris = NULL;
bool* ns_names_uris_nulls = NULL;
int ns_count = 0;
ndim = namespaces ? ARR_NDIM(namespaces) : 0;
if (ndim != 0) {
int* dim = NULL;
dim = ARR_DIMS(namespaces);
if (ndim != 2 && dim[1] != 2) {
ereport(ERROR, (errcode(ERRCODE_DATA_EXCEPTION),
errmsg("invalid array for XML namespaces mapping"),
errdetail("The array mast be two-dimensional with the length of second axis equal to 2.")));
} else {
ns_names_uris = NULL;
ns_names_uris_nulls = NULL;
ns_count = 0;
}
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);
ns_count /= 2;
}
xpath_expr = buildXpathAbsolutePath(xpath_expr_text);
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
doc = xml_parse(data, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
xpathctx = xmlXPathNewContext(doc);
if (xpathctx == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate XPath context");
}
xpathctx->node = xmlDocGetRootElement(doc);
if (xpathctx->node == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not find root XML element");
}
if (ns_count > 0) {
for (i = 0; i < ns_count; i++) {
char* ns_name = NULL;
char* ns_uri = NULL;
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_nulls[i * 2]);
ns_uri = TextDatumGetCString(ns_names_uris_nulls[i * 2 + 1]);
if (xmlXPathRegisterNs(xpathctx, (xmlChar*)ns_name, (xmlChar*)ns_uri) != 0) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not register XML namespace with name \"%s\" and \
URI \"%s\"", ns_name, ns_uri)));
}
}
}
xpathobj = xmlXPathEvalExpression(xpath_expr, xpathctx);
if (xpathobj == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_OPERATION, "could not create XPath object");
}
if (res_nitems != NULL) {
*res_nitems = xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
} else {
(void)xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
}
}
PG_CATCH();
{
if (xpathobj) {
xmlXPathFreeObject(xpathobj);
}
if (xpathctx) {
xmlXPathFreeContext(xpathctx);
}
if (doc) {
xmlFreeDoc(doc);
}
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlXPathFreeObject(xpathobj);
xmlXPathFreeContext(xpathctx);
xmlFreeDoc(doc);
pg_xml_done(xmlerrcxt, false);
}
* Get xmltype node value
*/
static char* xpath_extractvalue(xmltype* data, text* xpath_expr_text, ArrayType* namespaces)
{
PgXmlErrorContext* xmlerrcxt = NULL;
volatile xmlDocPtr doc = NULL;
volatile xmlXPathContextPtr xpathctx = NULL;
volatile xmlXPathObjectPtr xpathobj = NULL;
xmlChar* xpath_expr = NULL;
char* result = NULL;
xmlChar* value = NULL;
int i = 0;
int ndim = 0;
Datum* ns_names_uris = NULL;
bool* ns_names_uris_nulls = NULL;
int ns_count = 0;
int div_num = 2;
ndim = namespaces ? ARR_NDIM(namespaces) : 0;
if (ndim != 0) {
int* dim = NULL;
dim = ARR_DIMS(namespaces);
if (ndim != 2 && dim[1] != 2) {
ereport(ERROR, (errcode(ERRCODE_DATA_EXCEPTION),
errmsg("invalid array for XML namespaces mapping"),
errdetail("The array mast be two-dimensional with the length of second axis equal to 2.")));
} else {
ns_names_uris = NULL;
ns_names_uris_nulls = NULL;
ns_count = 0;
}
Assert(ARR_ELEMTYPE(namespaces) == TEXTOID);
deconstruct_array(namespaces, TEXTOID, -1, false, 'i', &ns_names_uris, &ns_names_uris_nulls, &ns_count);
Assert(ns_count % div_num == 0);
ns_count /= div_num;
}
xpath_expr = buildXpathAbsolutePath(xpath_expr_text);
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
PG_TRY();
{
doc = xml_parse(data, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
xpathctx = xmlXPathNewContext(doc);
if (xpathctx == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate XPath context");
}
xpathctx->node = xmlDocGetRootElement(doc);
if (xpathctx->node == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not find root XML element");
}
if (ns_count > 0) {
for (i = 0; i < ns_count; i++) {
char* ns_name = NULL;
char* ns_uri = NULL;
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_nulls[i * 2]);
ns_uri = TextDatumGetCString(ns_names_uris_nulls[i * 2 + 1]);
if (xmlXPathRegisterNs(xpathctx, (xmlChar*)ns_name, (xmlChar*)ns_uri) != 0) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not register XML namespace with name \"%s\" and URI \"%s\"", ns_name, ns_uri)));
}
}
}
xpathobj = xmlXPathEvalExpression(xpath_expr, xpathctx);
if (xpathobj == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_OPERATION, "could not create XPath object");
}
if (xpathobj->type == XPATH_NODESET && xpathobj->nodesetval != NULL) {
if (xpathobj->nodesetval->nodeNr > 1) {
xml_ereport(xmlerrcxt,
ERROR, ERRCODE_UNEXPECTED_NULL_VALUE, "EXTRACTVALUE returns value of only one node.");
} else if (xpathobj->nodesetval->nodeNr == 1) {
xmlNodePtr node = xpathobj->nodesetval->nodeTab[0];
value = xmlXPathCastNodeToString(node);
if (value) {
result = pstrdup((char*)value);
xmlFree(value);
value = NULL;
}
}
}
}
PG_CATCH();
{
if (xpathobj) {
xmlXPathFreeObject(xpathobj);
}
if (xpathctx) {
xmlXPathFreeContext(xpathctx);
}
if (doc) {
xmlFreeDoc(doc);
}
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
xmlXPathFreeObject(xpathobj);
xmlXPathFreeContext(xpathctx);
xmlFreeDoc(doc);
pg_xml_done(xmlerrcxt, false);
return result;
}
static char* appendNewChildXml(xmltype* rootxml, text* xpath_expr_text,
ArrayType* namespaces, text* appendData_text)
{
PgXmlErrorContext* xmlerrcxt = NULL;
xmlDocPtr doc = NULL;
xmlChar* xpathStr = NULL;
xmlNodePtr curNode = NULL;
xmlDocPtr appendDoc = NULL;
xmlNodePtr appendNode = NULL;
int i = 0;
int nodeSize = 0;
xmlChar* resdata = NULL;
int rescount = 0;
xmlXPathContextPtr xpathctx = NULL;
xmlXPathObjectPtr xpathObj = NULL;
Datum* ns_names_uris = NULL;
bool* ns_names_uris_nulls = NULL;
char* res = NULL;
int ns_count = 0;
int ndim;
xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
xpathStr = buildXpathAbsolutePath(xpath_expr_text);
ndim = namespaces ? ARR_NDIM(namespaces) : 0;
if (ndim != 0) {
int* dim = NULL;
dim = ARR_DIMS(namespaces);
if (ndim != 2 || dim[1] != 2) {
ereport(ERROR, (errcode(ERRCODE_DATA_EXCEPTION),
errmsg("invalid array for XML namespace mapping"),
errdetail("The array mast be two-dimensional with the length of 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);
ns_count /= 2;
} else {
ns_names_uris = NULL;
ns_names_uris_nulls = NULL;
ns_count = 0;
}
PG_TRY();
{
xmlKeepBlanksDefault(0);
doc = xml_parse(rootxml, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
xpathctx = xmlXPathNewContext(doc);
if (xpathctx == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY, "could not allocate XPath context");
}
xpathctx->node = xmlDocGetRootElement(doc);
if (xpathctx->node == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not find root XML element");
}
if (ns_count > 0) {
for (i = 0; i < ns_count; i++) {
char* ns_name = NULL;
char* ns_uri = NULL;
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, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not register XML namespace with name \"%s\" and URI \"%s\"", ns_name, ns_uri)));
}
}
}
xpathObj = xmlXPathEvalExpression(xpathStr, xpathctx);
if (xpathObj == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_OPERATION, "could not create XPath object");
}
char* appendstr = text_to_cstring(appendData_text);
if (appendstr[0] == '<') {
appendDoc = xml_parse(appendData_text, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
appendNode = xmlDocGetRootElement(appendDoc);
if (appendNode == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not find root XML element");
}
} else {
appendNode = xmlNewText((xmlChar*)appendstr);
if (appendNode == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_UNDEFINED_OBJECT, "could not parse XML content");
}
}
nodeSize = (xpathObj->nodesetval) ? xpathObj->nodesetval->nodeNr : 0;
for (i = 0; i < nodeSize; i++) {
curNode = xpathObj->nodesetval->nodeTab[i];
xmlNodePtr resNode = xmlAddChildList(curNode, xmlCopyNode(appendNode, 1));
if (resNode == NULL || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OPERATE_FAILED, "append child xml failed");
}
}
xmlDocDumpFormatMemory(doc, &resdata, &rescount, 1);
if (rescount == 0 || xmlerrcxt->err_occurred) {
xml_ereport(xmlerrcxt, ERROR, ERRCODE_OPERATE_FAILED, "xml document dump failed");
}
}
PG_CATCH();
{
if (xpathObj) {
xmlXPathFreeObject(xpathObj);
}
if (xpathctx) {
xmlXPathFreeContext(xpathctx);
}
if (appendDoc) {
xmlFreeDoc(appendDoc);
} else if (appendNode) {
xmlFreeNodeList(appendNode);
}
if (resdata) {
xmlFree(resdata);
}
if (doc) {
xmlFreeDoc(doc);
}
pg_xml_done(xmlerrcxt, true);
PG_RE_THROW();
}
PG_END_TRY();
res = pstrdup((char*)resdata);
xmlFree(resdata);
xmlXPathFreeObject(xpathObj);
xmlXPathFreeContext(xpathctx);
if (appendDoc) {
xmlFreeDoc(appendDoc);
} else if (appendNode) {
xmlFreeNodeList(appendNode);
}
xmlFreeDoc(doc);
pg_xml_done(xmlerrcxt, false);
return res;
}
#endif
static void XMLTYPE_SUPPORT()
{
if (u_sess->attr.attr_sql.sql_compatibility != A_FORMAT) {
ereport(ERROR, (errcode(ERRCODE_INVALID_OPERATION),
errmsg("Functions for xmltype are only supported in database which dbcompatibility = 'A'.")));
}
}
Datum xmltype_extract(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
if (PG_ARGISNULL(1)) {
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("Invalid XPATH expression")));
}
text* xpath_expr_text = PG_GETARG_TEXT_P(1);
xmltype* data = PG_GETARG_XML_P(0);
ArrayType* namespaces = PG_GETARG_ARRAYTYPE_P(2);
int res_nitems = 0;
ArrayBuildState* astate = NULL;
extract_internal(data, xpath_expr_text, namespaces, &res_nitems, &astate);
if (res_nitems == 0) {
PG_RETURN_NULL();
} else {
StringInfoData buf;
initStringInfo(&buf);
for (int i = 0; i < astate->nelems; ++i) {
if (astate->dnulls && astate->dnulls[i]) {
continue;
} else {
xmltype* xml = (xmltype*)astate->dvalues[i];
char* xmlchar = text_to_cstring((text*)xml);
appendStringInfo(&buf, "%s\n", xmlchar);
}
}
buf.data[buf.len - 1] = '\0';
buf.len--;
PG_RETURN_XML_P(stringinfo_to_xmltype(&buf));
}
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_extractvalue(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
text* xpath_expr_text = PG_GETARG_TEXT_P(1);
xmltype* data = PG_GETARG_XML_P(0);
ArrayType* namespaces = PG_GETARG_ARRAYTYPE_P(2);
char* resvalue = NULL;
resvalue = xpath_extractvalue(data, xpath_expr_text, namespaces);
if (resvalue == NULL) {
PG_RETURN_NULL();
}
PG_RETURN_CSTRING(cstring_to_text((char*)resvalue));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_xmlsequence(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
if (PG_ARGISNULL(0)) {
PG_RETURN_ARRAYTYPE_P(construct_empty_array(XMLOID));
}
xmltype* data = PG_GETARG_XML_P(0);
ArrayBuildState* astate = NULL;
MemoryContext oldcontext = CurrentMemoryContext;
PG_TRY();
{
xmlDocPtr doc = NULL;
doc = xml_parse(data, XMLOPTION_DOCUMENT, true, GetDatabaseEncoding());
xmlFreeDoc(doc);
astate = accumArrayResult(astate, PointerGetDatum(data), false, XMLOID, CurrentMemoryContext);
if (astate->nelems == 0) {
PG_RETURN_ARRAYTYPE_P(construct_empty_array(XMLOID));
} else {
PG_RETURN_ARRAYTYPE_P(makeArrayResult(astate, CurrentMemoryContext));
}
}
PG_CATCH();
{
FlushErrorState();
MemoryContextSwitchTo(oldcontext);
int res_nitems = 0;
StringInfoData buf;
initStringInfo(&buf);
char* node_open = "<begin>";
char* node_close = "</begin>";
appendStringInfo(&buf, "%s", node_open);
appendStringInfo(&buf, "%s", text_to_cstring((text*)data));
appendStringInfo(&buf, "%s", node_close);
xmltype* xmlbuf = stringinfo_to_xmltype(&buf);
char* xpath_root_node = "/begin/*";
text* xpath_root_path = cstring_to_text(xpath_root_node);
extract_internal(xmlbuf, xpath_root_path, NULL, &res_nitems, &astate);
if (res_nitems == 0) {
PG_RETURN_ARRAYTYPE_P(construct_empty_array(XMLOID));
} else {
PG_RETURN_ARRAYTYPE_P(makeArrayResult(astate, CurrentMemoryContext));
}
}
PG_END_TRY();
return 0;
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_xmlsequence_array(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
PG_RETURN_ARRAYTYPE_P(PG_GETARG_ARRAYTYPE_P(0));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_existsnode(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
text* xpath_expr_text = PG_GETARG_TEXT_P(1);
xmltype* data = PG_GETARG_XML_P(0);
int res_nitems = 0;
extract_internal(data, xpath_expr_text, NULL, &res_nitems, NULL);
if (res_nitems > 0) {
PG_RETURN_UINT8(1);
} else {
PG_RETURN_UINT8(0);
}
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_getstringval(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
xmltype* data = PG_GETARG_XML_P(0);
PG_RETURN_VARCHAR_P((VarChar*)data);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_getstringval_array(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
ArrayType* v = PG_GETARG_ARRAYTYPE_P(0);
if (ARR_NDIM(v) <= 0 || ARR_NDIM(v) > MAXDIM) {
PG_RETURN_NULL();
}
VarChar* resvalue;
FunctionCallInfoData info;
InitFunctionCallInfoData(info, fcinfo->flinfo, 2, InvalidOid, NULL, NULL);
info.arg[0] = fcinfo->arg[0];
info.arg[1] = CStringGetTextDatum(" \n");
info.argnull[0] = false;
info.argnull[1] = false;
resvalue = (VarChar*)DatumGetPointer(array_to_text(&info));
PG_RETURN_VARCHAR_P(resvalue);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xmltype_appendchildxml(PG_FUNCTION_ARGS)
{
XMLTYPE_SUPPORT();
#ifdef USE_LIBXML
if (PG_ARGISNULL(0)) {
ereport(ERROR, (errcode(ERRCODE_INVALID_XML_DOCUMENT),
errmsg("invaild xml tag, got no context")));
}
if (PG_ARGISNULL(1)) {
PG_RETURN_NULL();
}
if (PG_ARGISNULL(2)) {
PG_RETURN_XML_P(PG_GETARG_XML_P(0));
}
xmltype* data = PG_GETARG_XML_P(0);
text* xpath_expr_text = PG_GETARG_TEXT_P(1);
text* appendData = PG_GETARG_TEXT_P(2);
ArrayType* namespaces = NULL;
if (!PG_ARGISNULL(3)) {
namespaces = PG_GETARG_ARRAYTYPE_P(3);
}
char* res = appendNewChildXml(data, xpath_expr_text, namespaces, appendData);
PG_RETURN_XML_P(cstring_to_xmltype(res));
#else
NO_XML_SUPPORT();
return 0;
#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).
*/
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);
int res_nitems;
ArrayBuildState* astate = NULL;
xpath_internal(xpath_expr_text, data, namespaces, &res_nitems, &astate);
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
}
* Determines if the node specified by the supplied XPath exists
* in a given XML document, returning a boolean.
*/
Datum xmlexists(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
text* xpath_expr_text = PG_GETARG_TEXT_P(0);
xmltype* data = PG_GETARG_XML_P(1);
int res_nitems;
xpath_internal(xpath_expr_text, data, NULL, &res_nitems, NULL);
PG_RETURN_BOOL(res_nitems > 0);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
* Determines if the node specified by the supplied XPath exists
* in a given XML document, returning a boolean. Differs from
* xmlexists as it supports namespaces and is not defined in SQL/XML.
*/
Datum xpath_exists(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);
int res_nitems;
xpath_internal(xpath_expr_text, data, namespaces, &res_nitems, NULL);
PG_RETURN_BOOL(res_nitems > 0);
#else
NO_XML_SUPPORT();
return 0;
#endif
}
* Functions for checking well-formed-ness
*/
#ifdef USE_LIBXML
static bool wellformed_xml(text* data, XmlOptionType xmloption_arg)
{
bool result = false;
volatile xmlDocPtr doc = NULL;
PG_TRY();
{
doc = xml_parse(data, xmloption_arg, true, GetDatabaseEncoding());
result = true;
}
PG_CATCH();
{
FlushErrorState();
result = false;
}
PG_END_TRY();
if (doc)
xmlFreeDoc(doc);
return result;
}
#endif
Datum xml_is_well_formed(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
text* data = PG_GETARG_TEXT_P(0);
PG_RETURN_BOOL(wellformed_xml(data, (XmlOptionType)xmloption));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xml_is_well_formed_document(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
text* data = PG_GETARG_TEXT_P(0);
PG_RETURN_BOOL(wellformed_xml(data, XMLOPTION_DOCUMENT));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
Datum xml_is_well_formed_content(PG_FUNCTION_ARGS)
{
#ifdef USE_LIBXML
text* data = PG_GETARG_TEXT_P(0);
PG_RETURN_BOOL(wellformed_xml(data, XMLOPTION_CONTENT));
#else
NO_XML_SUPPORT();
return 0;
#endif
}
