Assorted code cleanup for contrib/xml2. No change in functionality,

just make it a bit less ugly in places.
This commit is contained in:
Tom Lane 2010-02-28 19:51:37 +00:00
parent bd7246f65e
commit a12333eed2
2 changed files with 145 additions and 181 deletions

View File

@ -1,5 +1,5 @@
/*
* $PostgreSQL: pgsql/contrib/xml2/xpath.c,v 1.25 2010/01/17 12:11:25 mha Exp $
* $PostgreSQL: pgsql/contrib/xml2/xpath.c,v 1.26 2010/02/28 19:51:37 tgl Exp $
*
* Parser interface for DOM-based parser (libxml) rather than
* stream-based SAX-type parser
@ -24,28 +24,7 @@
PG_MODULE_MAGIC;
/* declarations */
static void *pgxml_palloc(size_t size);
static void *pgxml_repalloc(void *ptr, size_t size);
static void pgxml_pfree(void *ptr);
static char *pgxml_pstrdup(const char *string);
static void pgxml_errorHandler(void *ctxt, const char *msg,...);
void elog_error(int level, char *explain, int force);
void pgxml_parser_init(void);
static xmlChar *pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
xmlChar *toptagname, xmlChar *septagname,
xmlChar *plainsep);
text *pgxml_result_to_text(xmlXPathObjectPtr res, xmlChar *toptag,
xmlChar *septag, xmlChar *plainsep);
xmlChar *pgxml_texttoxmlchar(text *textstring);
static xmlXPathObjectPtr pgxml_xpath(text *document, xmlChar *xpath);
/* externally accessible functions */
Datum xml_is_well_formed(PG_FUNCTION_ARGS);
Datum xml_encode_special_chars(PG_FUNCTION_ARGS);
@ -56,11 +35,34 @@ Datum xpath_bool(PG_FUNCTION_ARGS);
Datum xpath_list(PG_FUNCTION_ARGS);
Datum xpath_table(PG_FUNCTION_ARGS);
/* Global variables */
char *errbuf; /* per line error buffer */
char *pgxml_errorMsg = NULL; /* overall error message */
/* these are exported for use by xslt_proc.c */
void elog_error(const char *explain, bool force);
void pgxml_parser_init(void);
/* local declarations */
static void *pgxml_palloc(size_t size);
static void *pgxml_repalloc(void *ptr, size_t size);
static void pgxml_pfree(void *ptr);
static char *pgxml_pstrdup(const char *string);
static void pgxml_errorHandler(void *ctxt, const char *msg,...);
static xmlChar *pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
xmlChar *toptagname, xmlChar *septagname,
xmlChar *plainsep);
static text *pgxml_result_to_text(xmlXPathObjectPtr res, xmlChar *toptag,
xmlChar *septag, xmlChar *plainsep);
static xmlChar *pgxml_texttoxmlchar(text *textstring);
static xmlXPathObjectPtr pgxml_xpath(text *document, xmlChar *xpath);
/* Global variables */
static char *pgxml_errorMsg = NULL; /* overall error message */
#define ERRBUF_SIZE 200
/* memory handling passthrough functions (e.g. palloc, pstrdup are
currently macros, and the others might become so...) */
@ -92,75 +94,77 @@ pgxml_pstrdup(const char *string)
return pstrdup(string);
}
/* The error handling function. This formats an error message and sets
/*
* The error handling function. This formats an error message and sets
* a flag - an ereport will be issued prior to return
*/
static void
pgxml_errorHandler(void *ctxt, const char *msg,...)
{
char errbuf[1024]; /* per line error buffer */
va_list args;
/* Format the message */
va_start(args, msg);
vsnprintf(errbuf, ERRBUF_SIZE, msg, args);
vsnprintf(errbuf, sizeof(errbuf), msg, args);
va_end(args);
/* Now copy the argument across */
/* Store in, or append to, pgxml_errorMsg */
if (pgxml_errorMsg == NULL)
pgxml_errorMsg = pstrdup(errbuf);
else
{
int32 xsize = strlen(pgxml_errorMsg);
pgxml_errorMsg = repalloc(pgxml_errorMsg,
(size_t) (xsize + strlen(errbuf) + 1));
strncpy(&pgxml_errorMsg[xsize - 1], errbuf, strlen(errbuf));
pgxml_errorMsg[xsize + strlen(errbuf) - 1] = '\0';
size_t oldsize = strlen(pgxml_errorMsg);
size_t newsize = strlen(errbuf);
/*
* We intentionally discard the last char of the existing message,
* which should be a carriage return. (XXX wouldn't it be saner
* to keep it?)
*/
pgxml_errorMsg = repalloc(pgxml_errorMsg, oldsize + newsize);
memcpy(&pgxml_errorMsg[oldsize - 1], errbuf, newsize);
pgxml_errorMsg[oldsize + newsize - 1] = '\0';
}
memset(errbuf, 0, ERRBUF_SIZE);
}
/* This function reports the current message at the level specified */
/*
* This function ereports the current message if any. If force is true
* then an error is thrown even if pgxml_errorMsg hasn't been set.
*/
void
elog_error(int level, char *explain, int force)
elog_error(const char *explain, bool force)
{
if (force || (pgxml_errorMsg != NULL))
if (force || pgxml_errorMsg != NULL)
{
if (pgxml_errorMsg == NULL)
{
ereport(level, (errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
errmsg("%s", explain)));
}
ereport(ERROR,
(errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
errmsg("%s", explain)));
else
{
ereport(level, (errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
errmsg("%s:%s", explain, pgxml_errorMsg)));
pfree(pgxml_errorMsg);
}
ereport(ERROR,
(errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
errmsg("%s: %s", explain, pgxml_errorMsg)));
}
}
/*
* Initialize for xml parsing.
*/
void
pgxml_parser_init()
pgxml_parser_init(void)
{
/*
* This code could also set parser settings from user-supplied info.
* Quite how these settings are made is another matter :)
*/
xmlMemSetup(pgxml_pfree, pgxml_palloc, pgxml_repalloc, pgxml_pstrdup);
xmlInitParser();
/* Set up error handling */
pgxml_errorMsg = NULL;
xmlSetGenericErrorFunc(NULL, pgxml_errorHandler);
/* Replace libxml memory handling (DANGEROUS) */
xmlMemSetup(pgxml_pfree, pgxml_palloc, pgxml_repalloc, pgxml_pstrdup);
/* Initialize libxml */
xmlInitParser();
xmlSubstituteEntitiesDefault(1);
xmlLoadExtDtdDefaultValue = 1;
pgxml_errorMsg = NULL;
errbuf = palloc(200);
memset(errbuf, 0, 200);
}
@ -171,10 +175,9 @@ PG_FUNCTION_INFO_V1(xml_is_well_formed);
Datum
xml_is_well_formed(PG_FUNCTION_ARGS)
{
/* called as xml_is_well_formed(document) */
xmlDocPtr doctree;
text *t = PG_GETARG_TEXT_P(0); /* document buffer */
int32 docsize = VARSIZE(t) - VARHDRSZ;
xmlDocPtr doctree;
pgxml_parser_init();
@ -184,8 +187,8 @@ xml_is_well_formed(PG_FUNCTION_ARGS)
xmlCleanupParser();
PG_RETURN_BOOL(false); /* i.e. not well-formed */
}
xmlCleanupParser();
xmlFreeDoc(doctree);
xmlCleanupParser();
PG_RETURN_BOOL(true);
}
@ -215,28 +218,23 @@ xml_encode_special_chars(PG_FUNCTION_ARGS)
PG_RETURN_TEXT_P(tout);
}
static xmlChar
*
/*
* Function translates a nodeset into a text representation
*
* iterates over each node in the set and calls xmlNodeDump to write it to
* an xmlBuffer -from which an xmlChar * string is returned.
*
* each representation is surrounded by <tagname> ... </tagname>
*
* plainsep is an ordinary (not tag) separator - if used, then nodes are
* cast to string as output method
*/
static xmlChar *
pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
xmlChar *toptagname,
xmlChar *septagname,
xmlChar *plainsep)
{
/* Function translates a nodeset into a text representation */
/*
* iterates over each node in the set and calls xmlNodeDump to write it to
* an xmlBuffer -from which an xmlChar * string is returned.
*/
/* each representation is surrounded by <tagname> ... </tagname> */
/*
* plainsep is an ordinary (not tag) seperator - if used, then nodes are
* cast to string as output method
*/
xmlBufferPtr buf;
xmlChar *result;
int i;
@ -253,7 +251,6 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
{
for (i = 0; i < nodeset->nodeNr; i++)
{
if (plainsep != NULL)
{
xmlBufferWriteCHAR(buf,
@ -265,8 +262,6 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
}
else
{
if ((septagname != NULL) && (xmlStrlen(septagname) > 0))
{
xmlBufferWriteChar(buf, "<");
@ -303,19 +298,18 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
/* Translate a PostgreSQL "varlena" -i.e. a variable length parameter
* into the libxml2 representation
*/
xmlChar *
static xmlChar *
pgxml_texttoxmlchar(text *textstring)
{
return (xmlChar *) text_to_cstring(textstring);
}
/* Public visible XPath functions */
/* Publicly visible XPath functions */
/* This is a "raw" xpath function. Check that it returns child elements
/*
* This is a "raw" xpath function. Check that it returns child elements
* properly
*/
PG_FUNCTION_INFO_V1(xpath_nodeset);
Datum
@ -325,8 +319,7 @@ xpath_nodeset(PG_FUNCTION_ARGS)
*toptag,
*septag;
int32 pathsize;
text
*xpathsupp,
text *xpathsupp,
*xpres;
/* PG_GETARG_TEXT_P(0) is document buffer */
@ -339,8 +332,7 @@ xpath_nodeset(PG_FUNCTION_ARGS)
xpath = pgxml_texttoxmlchar(xpathsupp);
xpres = pgxml_result_to_text(
pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
xpres = pgxml_result_to_text(pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
toptag, septag, NULL);
/* xmlCleanupParser(); done by result_to_text routine */
@ -351,9 +343,10 @@ xpath_nodeset(PG_FUNCTION_ARGS)
PG_RETURN_TEXT_P(xpres);
}
/* The following function is almost identical, but returns the elements in */
/* a list. */
/*
* The following function is almost identical, but returns the elements in
* a list.
*/
PG_FUNCTION_INFO_V1(xpath_list);
Datum
@ -362,8 +355,7 @@ xpath_list(PG_FUNCTION_ARGS)
xmlChar *xpath,
*plainsep;
int32 pathsize;
text
*xpathsupp,
text *xpathsupp,
*xpres;
/* PG_GETARG_TEXT_P(0) is document buffer */
@ -375,8 +367,7 @@ xpath_list(PG_FUNCTION_ARGS)
xpath = pgxml_texttoxmlchar(xpathsupp);
xpres = pgxml_result_to_text(
pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
xpres = pgxml_result_to_text(pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
NULL, NULL, plainsep);
/* xmlCleanupParser(); done by result_to_text routine */
@ -395,8 +386,7 @@ xpath_string(PG_FUNCTION_ARGS)
{
xmlChar *xpath;
int32 pathsize;
text
*xpathsupp,
text *xpathsupp,
*xpres;
/* PG_GETARG_TEXT_P(0) is document buffer */
@ -416,8 +406,7 @@ xpath_string(PG_FUNCTION_ARGS)
xpath[pathsize + 7] = ')';
xpath[pathsize + 8] = '\0';
xpres = pgxml_result_to_text(
pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
xpres = pgxml_result_to_text(pgxml_xpath(PG_GETARG_TEXT_P(0), xpath),
NULL, NULL, NULL);
xmlCleanupParser();
@ -436,9 +425,7 @@ xpath_number(PG_FUNCTION_ARGS)
{
xmlChar *xpath;
int32 pathsize;
text
*xpathsupp;
text *xpathsupp;
float4 fRes;
xmlXPathObjectPtr res;
@ -465,7 +452,6 @@ xpath_number(PG_FUNCTION_ARGS)
PG_RETURN_NULL();
PG_RETURN_FLOAT4(fRes);
}
@ -476,9 +462,7 @@ xpath_bool(PG_FUNCTION_ARGS)
{
xmlChar *xpath;
int32 pathsize;
text
*xpathsupp;
text *xpathsupp;
int bRes;
xmlXPathObjectPtr res;
@ -502,26 +486,21 @@ xpath_bool(PG_FUNCTION_ARGS)
bRes = xmlXPathCastToBoolean(res);
xmlCleanupParser();
PG_RETURN_BOOL(bRes);
}
/* Core function to evaluate XPath query */
xmlXPathObjectPtr
static xmlXPathObjectPtr
pgxml_xpath(text *document, xmlChar *xpath)
{
xmlDocPtr doctree;
xmlXPathContextPtr ctxt;
xmlXPathObjectPtr res;
xmlXPathCompExprPtr comppath;
int32 docsize;
docsize = VARSIZE(document) - VARHDRSZ;
pgxml_parser_init();
@ -535,16 +514,13 @@ pgxml_xpath(text *document, xmlChar *xpath)
ctxt = xmlXPathNewContext(doctree);
ctxt->node = xmlDocGetRootElement(doctree);
/* compile the path */
comppath = xmlXPathCompile(xpath);
if (comppath == NULL)
{
xmlCleanupParser();
xmlFreeDoc(doctree);
elog_error(ERROR, "XPath Syntax Error", 1);
return NULL;
elog_error("XPath Syntax Error", true);
}
/* Now evaluate the path expression. */
@ -563,8 +539,7 @@ pgxml_xpath(text *document, xmlChar *xpath)
return res;
}
text
*
static text *
pgxml_result_to_text(xmlXPathObjectPtr res,
xmlChar *toptag,
xmlChar *septag,
@ -595,7 +570,6 @@ pgxml_result_to_text(xmlXPathObjectPtr res,
xpresstr = xmlStrdup((const xmlChar *) "<unsupported/>");
}
/* Now convert this result back to text */
xpres = cstring_to_text((char *) xpresstr);
@ -605,27 +579,33 @@ pgxml_result_to_text(xmlXPathObjectPtr res,
xmlFree(xpresstr);
elog_error(ERROR, "XPath error", 0);
elog_error("XPath error", false);
return xpres;
}
/* xpath_table is a table function. It needs some tidying (as do the
/*
* xpath_table is a table function. It needs some tidying (as do the
* other functions here!
*/
PG_FUNCTION_INFO_V1(xpath_table);
Datum
xpath_table(PG_FUNCTION_ARGS)
{
/* SPI (input tuple) support */
/* Function parameters */
char *pkeyfield = text_to_cstring(PG_GETARG_TEXT_PP(0));
char *xmlfield = text_to_cstring(PG_GETARG_TEXT_PP(1));
char *relname = text_to_cstring(PG_GETARG_TEXT_PP(2));
char *xpathset = text_to_cstring(PG_GETARG_TEXT_PP(3));
char *condition = text_to_cstring(PG_GETARG_TEXT_PP(4));
/* SPI (input tuple) support */
SPITupleTable *tuptable;
HeapTuple spi_tuple;
TupleDesc spi_tupdesc;
/* Output tuple (tuplestore) support */
/* Output tuple (tuplestore) support */
Tuplestorestate *tupstore = NULL;
TupleDesc ret_tupdesc;
HeapTuple ret_tuple;
@ -635,13 +615,6 @@ xpath_table(PG_FUNCTION_ARGS)
MemoryContext per_query_ctx;
MemoryContext oldcontext;
/* Function parameters */
char *pkeyfield = text_to_cstring(PG_GETARG_TEXT_PP(0));
char *xmlfield = text_to_cstring(PG_GETARG_TEXT_PP(1));
char *relname = text_to_cstring(PG_GETARG_TEXT_PP(2));
char *xpathset = text_to_cstring(PG_GETARG_TEXT_PP(3));
char *condition = text_to_cstring(PG_GETARG_TEXT_PP(4));
char **values;
xmlChar **xpaths;
char *pos;
@ -655,7 +628,6 @@ xpath_table(PG_FUNCTION_ARGS)
int rownr; /* For issuing multiple rows from one original
* document */
int had_values; /* To determine end of nodeset results */
StringInfoData query_buf;
/* We only have a valid tuple description in table function mode */
@ -743,30 +715,28 @@ xpath_table(PG_FUNCTION_ARGS)
pkeyfield,
xmlfield,
relname,
condition
);
condition);
if ((ret = SPI_connect()) < 0)
elog(ERROR, "xpath_table: SPI_connect returned %d", ret);
if ((ret = SPI_exec(query_buf.data, 0)) != SPI_OK_SELECT)
elog(ERROR, "xpath_table: SPI execution failed for query %s", query_buf.data);
elog(ERROR, "xpath_table: SPI execution failed for query %s",
query_buf.data);
proc = SPI_processed;
/* elog(DEBUG1,"xpath_table: SPI returned %d rows",proc); */
tuptable = SPI_tuptable;
spi_tupdesc = tuptable->tupdesc;
/* Switch out of SPI context */
/* Switch out of SPI context */
MemoryContextSwitchTo(oldcontext);
/* Check that SPI returned correct result. If you put a comma into one of
* the function parameters, this will catch it when the SPI query returns
* e.g. 3 columns.
*/
/*
* Check that SPI returned correct result. If you put a comma into one of
* the function parameters, this will catch it when the SPI query returns
* e.g. 3 columns.
*/
if (spi_tupdesc->natts != 2)
{
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
@ -774,10 +744,12 @@ xpath_table(PG_FUNCTION_ARGS)
errdetail("Expected two columns in SPI result, got %d.", spi_tupdesc->natts)));
}
/* Setup the parser. Beware that this must happen in the same context as the
* cleanup - which means that any error from here on must do cleanup to
* ensure that the entity table doesn't get freed by being out of context.
*/
/*
* Setup the parser. Beware that this must happen in the same context as
* the cleanup - which means that any error from here on must do cleanup
* to ensure that the entity table doesn't get freed by being out of
* context.
*/
pgxml_parser_init();
/* For each row i.e. document returned from SPI */
@ -785,13 +757,10 @@ xpath_table(PG_FUNCTION_ARGS)
{
char *pkey;
char *xmldoc;
xmlDocPtr doctree;
xmlXPathContextPtr ctxt;
xmlXPathObjectPtr res;
xmlChar *resstr;
xmlXPathCompExprPtr comppath;
/* Extract the row data as C Strings */
@ -801,10 +770,9 @@ xpath_table(PG_FUNCTION_ARGS)
/*
* Clear the values array, so that not-well-formed documents return
* NULL in all columns.
* NULL in all columns. Note that this also means that spare columns
* will be NULL.
*/
/* Note that this also means that spare columns will be NULL. */
for (j = 0; j < ret_tupdesc->natts; j++)
values[j] = NULL;
@ -835,7 +803,6 @@ xpath_table(PG_FUNCTION_ARGS)
had_values = 0;
for (j = 0; j < numpaths; j++)
{
ctxt = xmlXPathNewContext(doctree);
ctxt->node = xmlDocGetRootElement(doctree);
xmlSetGenericErrorFunc(ctxt, pgxml_errorHandler);
@ -847,7 +814,7 @@ xpath_table(PG_FUNCTION_ARGS)
xmlCleanupParser();
xmlFreeDoc(doctree);
elog_error(ERROR, "XPath Syntax Error", 1);
elog_error("XPath Syntax Error", true);
PG_RETURN_NULL(); /* Keep compiler happy */
}
@ -882,7 +849,6 @@ xpath_table(PG_FUNCTION_ARGS)
resstr = xmlStrdup((const xmlChar *) "<unsupported/>");
}
/*
* Insert this into the appropriate column in the
* result tuple.
@ -891,6 +857,7 @@ xpath_table(PG_FUNCTION_ARGS)
}
xmlXPathFreeContext(ctxt);
}
/* Now add the tuple to the output, if there is one. */
if (had_values)
{
@ -900,9 +867,7 @@ xpath_table(PG_FUNCTION_ARGS)
}
rownr++;
} while (had_values);
}
xmlFreeDoc(doctree);
@ -914,7 +879,7 @@ xpath_table(PG_FUNCTION_ARGS)
}
xmlCleanupParser();
/* Needed to flag completeness in 7.3.1. 7.4 defines it as a no-op. */
tuplestore_donestoring(tupstore);
SPI_finish();
@ -929,5 +894,4 @@ xpath_table(PG_FUNCTION_ARGS)
* expecting.
*/
return (Datum) 0;
}

View File

@ -1,5 +1,5 @@
/*
* $PostgreSQL: pgsql/contrib/xml2/xslt_proc.c,v 1.16 2009/07/10 00:32:00 tgl Exp $
* $PostgreSQL: pgsql/contrib/xml2/xslt_proc.c,v 1.17 2010/02/28 19:51:37 tgl Exp $
*
* XSLT processing functions (requiring libxslt)
*
@ -27,16 +27,16 @@
#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);
/* externally accessible functions */
Datum xslt_process(PG_FUNCTION_ARGS);
/* declarations to come from xpath.c */
extern void elog_error(const char *explain, bool force);
extern void pgxml_parser_init(void);
/* local defs */
static void parse_params(const char **params, text *paramstr);
#define MAXPARAMS 20 /* must be even, see parse_params() */
@ -80,7 +80,7 @@ xslt_process(PG_FUNCTION_ARGS)
if (doctree == NULL)
{
xmlCleanupParser();
elog_error(ERROR, "error parsing XML document", 0);
elog_error("error parsing XML document", false);
PG_RETURN_NULL();
}
@ -94,7 +94,7 @@ xslt_process(PG_FUNCTION_ARGS)
{
xmlFreeDoc(doctree);
xmlCleanupParser();
elog_error(ERROR, "error parsing stylesheet as XML document", 0);
elog_error("error parsing stylesheet as XML document", false);
PG_RETURN_NULL();
}
@ -109,7 +109,7 @@ xslt_process(PG_FUNCTION_ARGS)
xmlFreeDoc(doctree);
xsltCleanupGlobals();
xmlCleanupParser();
elog_error(ERROR, "failed to parse stylesheet", 0);
elog_error("failed to parse stylesheet", false);
PG_RETURN_NULL();
}