postgresql/contrib/hstore_plpython/hstore_plpython.c

187 lines
5.1 KiB
C

#include "postgres.h"
#include "fmgr.h"
#include "hstore/hstore.h"
#include "plpy_typeio.h"
#include "plpython.h"
PG_MODULE_MAGIC;
extern void _PG_init(void);
/* Linkage to functions in plpython module */
typedef char *(*PLyObject_AsString_t) (PyObject *plrv);
static PLyObject_AsString_t PLyObject_AsString_p;
typedef PyObject *(*PLyUnicode_FromStringAndSize_t) (const char *s, Py_ssize_t size);
static PLyUnicode_FromStringAndSize_t PLyUnicode_FromStringAndSize_p;
/* Linkage to functions in hstore module */
typedef HStore *(*hstoreUpgrade_t) (Datum orig);
static hstoreUpgrade_t hstoreUpgrade_p;
typedef int (*hstoreUniquePairs_t) (Pairs *a, int32 l, int32 *buflen);
static hstoreUniquePairs_t hstoreUniquePairs_p;
typedef HStore *(*hstorePairs_t) (Pairs *pairs, int32 pcount, int32 buflen);
static hstorePairs_t hstorePairs_p;
typedef size_t (*hstoreCheckKeyLen_t) (size_t len);
static hstoreCheckKeyLen_t hstoreCheckKeyLen_p;
typedef size_t (*hstoreCheckValLen_t) (size_t len);
static hstoreCheckValLen_t hstoreCheckValLen_p;
/*
* Module initialize function: fetch function pointers for cross-module calls.
*/
void
_PG_init(void)
{
/* Asserts verify that typedefs above match original declarations */
AssertVariableIsOfType(&PLyObject_AsString, PLyObject_AsString_t);
PLyObject_AsString_p = (PLyObject_AsString_t)
load_external_function("$libdir/" PLPYTHON_LIBNAME, "PLyObject_AsString",
true, NULL);
AssertVariableIsOfType(&PLyUnicode_FromStringAndSize, PLyUnicode_FromStringAndSize_t);
PLyUnicode_FromStringAndSize_p = (PLyUnicode_FromStringAndSize_t)
load_external_function("$libdir/" PLPYTHON_LIBNAME, "PLyUnicode_FromStringAndSize",
true, NULL);
AssertVariableIsOfType(&hstoreUpgrade, hstoreUpgrade_t);
hstoreUpgrade_p = (hstoreUpgrade_t)
load_external_function("$libdir/hstore", "hstoreUpgrade",
true, NULL);
AssertVariableIsOfType(&hstoreUniquePairs, hstoreUniquePairs_t);
hstoreUniquePairs_p = (hstoreUniquePairs_t)
load_external_function("$libdir/hstore", "hstoreUniquePairs",
true, NULL);
AssertVariableIsOfType(&hstorePairs, hstorePairs_t);
hstorePairs_p = (hstorePairs_t)
load_external_function("$libdir/hstore", "hstorePairs",
true, NULL);
AssertVariableIsOfType(&hstoreCheckKeyLen, hstoreCheckKeyLen_t);
hstoreCheckKeyLen_p = (hstoreCheckKeyLen_t)
load_external_function("$libdir/hstore", "hstoreCheckKeyLen",
true, NULL);
AssertVariableIsOfType(&hstoreCheckValLen, hstoreCheckValLen_t);
hstoreCheckValLen_p = (hstoreCheckValLen_t)
load_external_function("$libdir/hstore", "hstoreCheckValLen",
true, NULL);
}
/* These defines must be after the module init function */
#define PLyObject_AsString PLyObject_AsString_p
#define PLyUnicode_FromStringAndSize PLyUnicode_FromStringAndSize_p
#define hstoreUpgrade hstoreUpgrade_p
#define hstoreUniquePairs hstoreUniquePairs_p
#define hstorePairs hstorePairs_p
#define hstoreCheckKeyLen hstoreCheckKeyLen_p
#define hstoreCheckValLen hstoreCheckValLen_p
PG_FUNCTION_INFO_V1(hstore_to_plpython);
Datum
hstore_to_plpython(PG_FUNCTION_ARGS)
{
HStore *in = PG_GETARG_HSTORE_P(0);
int i;
int count = HS_COUNT(in);
char *base = STRPTR(in);
HEntry *entries = ARRPTR(in);
PyObject *dict;
dict = PyDict_New();
if (!dict)
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
for (i = 0; i < count; i++)
{
PyObject *key;
key = PLyUnicode_FromStringAndSize(HSTORE_KEY(entries, base, i),
HSTORE_KEYLEN(entries, i));
if (HSTORE_VALISNULL(entries, i))
PyDict_SetItem(dict, key, Py_None);
else
{
PyObject *value;
value = PLyUnicode_FromStringAndSize(HSTORE_VAL(entries, base, i),
HSTORE_VALLEN(entries, i));
PyDict_SetItem(dict, key, value);
Py_XDECREF(value);
}
Py_XDECREF(key);
}
return PointerGetDatum(dict);
}
PG_FUNCTION_INFO_V1(plpython_to_hstore);
Datum
plpython_to_hstore(PG_FUNCTION_ARGS)
{
PyObject *dict;
PyObject *volatile items;
Py_ssize_t pcount;
HStore *volatile out;
dict = (PyObject *) PG_GETARG_POINTER(0);
if (!PyMapping_Check(dict))
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("not a Python mapping")));
pcount = PyMapping_Size(dict);
items = PyMapping_Items(dict);
PG_TRY();
{
int32 buflen;
Py_ssize_t i;
Pairs *pairs;
pairs = palloc(pcount * sizeof(*pairs));
for (i = 0; i < pcount; i++)
{
PyObject *tuple;
PyObject *key;
PyObject *value;
tuple = PyList_GetItem(items, i);
key = PyTuple_GetItem(tuple, 0);
value = PyTuple_GetItem(tuple, 1);
pairs[i].key = PLyObject_AsString(key);
pairs[i].keylen = hstoreCheckKeyLen(strlen(pairs[i].key));
pairs[i].needfree = true;
if (value == Py_None)
{
pairs[i].val = NULL;
pairs[i].vallen = 0;
pairs[i].isnull = true;
}
else
{
pairs[i].val = PLyObject_AsString(value);
pairs[i].vallen = hstoreCheckValLen(strlen(pairs[i].val));
pairs[i].isnull = false;
}
}
pcount = hstoreUniquePairs(pairs, pcount, &buflen);
out = hstorePairs(pairs, pcount, buflen);
}
PG_FINALLY();
{
Py_DECREF(items);
}
PG_END_TRY();
PG_RETURN_POINTER(out);
}