postgresql/contrib/xml2/xslt_proc.c
Tom Lane 45173ae24e Use new cstring/text conversion functions in some additional places.
These changes assume that the varchar and xml data types are represented
the same as text.  (I did not, however, accept the portions of the proposed
patch that wanted to assume bytea is the same as text --- tgl.)

Brendan Jurd
2008-05-04 16:42:41 +00:00

170 lines
3.2 KiB
C

/* XSLT processing functions (requiring libxslt) */
/* John Gray, for Torchbox 2003-04-01 */
#include "postgres.h"
#include "fmgr.h"
#include "executor/spi.h"
#include "funcapi.h"
#include "miscadmin.h"
/* libxml includes */
#include <libxml/xpath.h>
#include <libxml/tree.h>
#include <libxml/xmlmemory.h>
/* libxslt includes */
#include <libxslt/xslt.h>
#include <libxslt/xsltInternals.h>
#include <libxslt/transform.h>
#include <libxslt/xsltutils.h>
/* declarations to come from xpath.c */
extern void elog_error(int level, char *explain, int force);
extern void pgxml_parser_init();
extern xmlChar *pgxml_texttoxmlchar(text *textstring);
/* local defs */
static void parse_params(const char **params, text *paramstr);
Datum xslt_process(PG_FUNCTION_ARGS);
#define MAXPARAMS 20
PG_FUNCTION_INFO_V1(xslt_process);
Datum
xslt_process(PG_FUNCTION_ARGS)
{
text *doct = PG_GETARG_TEXT_P(0);
text *ssheet = PG_GETARG_TEXT_P(1);
text *paramstr;
const char *params[MAXPARAMS + 1]; /* +1 for the terminator */
xsltStylesheetPtr stylesheet = NULL;
xmlDocPtr doctree;
xmlDocPtr restree;
xmlDocPtr ssdoc = NULL;
xmlChar *resstr;
int resstat;
int reslen;
if (fcinfo->nargs == 3)
{
paramstr = PG_GETARG_TEXT_P(2);
parse_params(params, paramstr);
}
else
/* No parameters */
params[0] = NULL;
/* Setup parser */
pgxml_parser_init();
/* Check to see if document is a file or a literal */
if (VARDATA(doct)[0] == '<')
doctree = xmlParseMemory((char *) VARDATA(doct), VARSIZE(doct) - VARHDRSZ);
else
doctree = xmlParseFile(text_to_cstring(doct));
if (doctree == NULL)
{
xmlCleanupParser();
elog_error(ERROR, "error parsing XML document", 0);
PG_RETURN_NULL();
}
/* Same for stylesheet */
if (VARDATA(ssheet)[0] == '<')
{
ssdoc = xmlParseMemory((char *) VARDATA(ssheet),
VARSIZE(ssheet) - VARHDRSZ);
if (ssdoc == NULL)
{
xmlFreeDoc(doctree);
xmlCleanupParser();
elog_error(ERROR, "error parsing stylesheet as XML document", 0);
PG_RETURN_NULL();
}
stylesheet = xsltParseStylesheetDoc(ssdoc);
}
else
stylesheet = xsltParseStylesheetFile((xmlChar *) text_to_cstring(ssheet));
if (stylesheet == NULL)
{
xmlFreeDoc(doctree);
xsltCleanupGlobals();
xmlCleanupParser();
elog_error(ERROR, "failed to parse stylesheet", 0);
PG_RETURN_NULL();
}
restree = xsltApplyStylesheet(stylesheet, doctree, params);
resstat = xsltSaveResultToString(&resstr, &reslen, restree, stylesheet);
xsltFreeStylesheet(stylesheet);
xmlFreeDoc(restree);
xmlFreeDoc(doctree);
xsltCleanupGlobals();
xmlCleanupParser();
if (resstat < 0)
PG_RETURN_NULL();
PG_RETURN_TEXT_P(cstring_to_text_with_len(resstr, reslen));
}
void
parse_params(const char **params, text *paramstr)
{
char *pos;
char *pstr;
int i;
char *nvsep = "=";
char *itsep = ",";
pstr = text_to_cstring(paramstr);
pos = pstr;
for (i = 0; i < MAXPARAMS; i++)
{
params[i] = pos;
pos = strstr(pos, nvsep);
if (pos != NULL)
{
*pos = '\0';
pos++;
}
else
{
params[i] = NULL;
break;
}
/* Value */
i++;
params[i] = pos;
pos = strstr(pos, itsep);
if (pos != NULL)
{
*pos = '\0';
pos++;
}
else
break;
}
if (i < MAXPARAMS)
params[i + 1] = NULL;
}