1 #include "postgres.h"
2 
3 #include "fmgr.h"
4 #include "plpython.h"
5 #include "plpy_typeio.h"
6 #include "hstore.h"
7 
8 PG_MODULE_MAGIC;
9 
10 extern void _PG_init(void);
11 
12 /* Linkage to functions in plpython module */
13 typedef char *(*PLyObject_AsString_t) (PyObject *plrv);
14 static PLyObject_AsString_t PLyObject_AsString_p;
15 #if PY_MAJOR_VERSION >= 3
16 typedef PyObject *(*PLyUnicode_FromStringAndSize_t) (const char *s, Py_ssize_t size);
17 static PLyUnicode_FromStringAndSize_t PLyUnicode_FromStringAndSize_p;
18 #endif
19 
20 /* Linkage to functions in hstore module */
21 typedef HStore *(*hstoreUpgrade_t) (Datum orig);
22 static hstoreUpgrade_t hstoreUpgrade_p;
23 typedef int (*hstoreUniquePairs_t) (Pairs *a, int32 l, int32 *buflen);
24 static hstoreUniquePairs_t hstoreUniquePairs_p;
25 typedef HStore *(*hstorePairs_t) (Pairs *pairs, int32 pcount, int32 buflen);
26 static hstorePairs_t hstorePairs_p;
27 typedef size_t (*hstoreCheckKeyLen_t) (size_t len);
28 static hstoreCheckKeyLen_t hstoreCheckKeyLen_p;
29 typedef size_t (*hstoreCheckValLen_t) (size_t len);
30 static hstoreCheckValLen_t hstoreCheckValLen_p;
31 
32 
33 /*
34  * Module initialize function: fetch function pointers for cross-module calls.
35  */
36 void
_PG_init(void)37 _PG_init(void)
38 {
39 	/* Asserts verify that typedefs above match original declarations */
40 	AssertVariableIsOfType(&PLyObject_AsString, PLyObject_AsString_t);
41 	PLyObject_AsString_p = (PLyObject_AsString_t)
42 		load_external_function("$libdir/" PLPYTHON_LIBNAME, "PLyObject_AsString",
43 							   true, NULL);
44 #if PY_MAJOR_VERSION >= 3
45 	AssertVariableIsOfType(&PLyUnicode_FromStringAndSize, PLyUnicode_FromStringAndSize_t);
46 	PLyUnicode_FromStringAndSize_p = (PLyUnicode_FromStringAndSize_t)
47 		load_external_function("$libdir/" PLPYTHON_LIBNAME, "PLyUnicode_FromStringAndSize",
48 							   true, NULL);
49 #endif
50 	AssertVariableIsOfType(&hstoreUpgrade, hstoreUpgrade_t);
51 	hstoreUpgrade_p = (hstoreUpgrade_t)
52 		load_external_function("$libdir/hstore", "hstoreUpgrade",
53 							   true, NULL);
54 	AssertVariableIsOfType(&hstoreUniquePairs, hstoreUniquePairs_t);
55 	hstoreUniquePairs_p = (hstoreUniquePairs_t)
56 		load_external_function("$libdir/hstore", "hstoreUniquePairs",
57 							   true, NULL);
58 	AssertVariableIsOfType(&hstorePairs, hstorePairs_t);
59 	hstorePairs_p = (hstorePairs_t)
60 		load_external_function("$libdir/hstore", "hstorePairs",
61 							   true, NULL);
62 	AssertVariableIsOfType(&hstoreCheckKeyLen, hstoreCheckKeyLen_t);
63 	hstoreCheckKeyLen_p = (hstoreCheckKeyLen_t)
64 		load_external_function("$libdir/hstore", "hstoreCheckKeyLen",
65 							   true, NULL);
66 	AssertVariableIsOfType(&hstoreCheckValLen, hstoreCheckValLen_t);
67 	hstoreCheckValLen_p = (hstoreCheckValLen_t)
68 		load_external_function("$libdir/hstore", "hstoreCheckValLen",
69 							   true, NULL);
70 }
71 
72 
73 /* These defines must be after the module init function */
74 #define PLyObject_AsString PLyObject_AsString_p
75 #define PLyUnicode_FromStringAndSize PLyUnicode_FromStringAndSize_p
76 #define hstoreUpgrade hstoreUpgrade_p
77 #define hstoreUniquePairs hstoreUniquePairs_p
78 #define hstorePairs hstorePairs_p
79 #define hstoreCheckKeyLen hstoreCheckKeyLen_p
80 #define hstoreCheckValLen hstoreCheckValLen_p
81 
82 
83 PG_FUNCTION_INFO_V1(hstore_to_plpython);
84 
85 Datum
hstore_to_plpython(PG_FUNCTION_ARGS)86 hstore_to_plpython(PG_FUNCTION_ARGS)
87 {
88 	HStore	   *in = PG_GETARG_HS(0);
89 	int			i;
90 	int			count = HS_COUNT(in);
91 	char	   *base = STRPTR(in);
92 	HEntry	   *entries = ARRPTR(in);
93 	PyObject   *dict;
94 
95 	dict = PyDict_New();
96 
97 	for (i = 0; i < count; i++)
98 	{
99 		PyObject   *key;
100 
101 		key = PyString_FromStringAndSize(HSTORE_KEY(entries, base, i),
102 										 HSTORE_KEYLEN(entries, i));
103 		if (HSTORE_VALISNULL(entries, i))
104 			PyDict_SetItem(dict, key, Py_None);
105 		else
106 		{
107 			PyObject   *value;
108 
109 			value = PyString_FromStringAndSize(HSTORE_VAL(entries, base, i),
110 											   HSTORE_VALLEN(entries, i));
111 			PyDict_SetItem(dict, key, value);
112 			Py_XDECREF(value);
113 		}
114 		Py_XDECREF(key);
115 	}
116 
117 	return PointerGetDatum(dict);
118 }
119 
120 
121 PG_FUNCTION_INFO_V1(plpython_to_hstore);
122 
123 Datum
plpython_to_hstore(PG_FUNCTION_ARGS)124 plpython_to_hstore(PG_FUNCTION_ARGS)
125 {
126 	PyObject   *dict;
127 	PyObject *volatile items = NULL;
128 	int32		pcount;
129 	HStore	   *out;
130 
131 	dict = (PyObject *) PG_GETARG_POINTER(0);
132 	if (!PyMapping_Check(dict))
133 		ereport(ERROR,
134 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
135 				 errmsg("not a Python mapping")));
136 
137 	pcount = PyMapping_Size(dict);
138 	items = PyMapping_Items(dict);
139 
140 	PG_TRY();
141 	{
142 		int32		buflen;
143 		int32		i;
144 		Pairs	   *pairs;
145 
146 		pairs = palloc(pcount * sizeof(*pairs));
147 
148 		for (i = 0; i < pcount; i++)
149 		{
150 			PyObject   *tuple;
151 			PyObject   *key;
152 			PyObject   *value;
153 
154 			tuple = PyList_GetItem(items, i);
155 			key = PyTuple_GetItem(tuple, 0);
156 			value = PyTuple_GetItem(tuple, 1);
157 
158 			pairs[i].key = PLyObject_AsString(key);
159 			pairs[i].keylen = hstoreCheckKeyLen(strlen(pairs[i].key));
160 			pairs[i].needfree = true;
161 
162 			if (value == Py_None)
163 			{
164 				pairs[i].val = NULL;
165 				pairs[i].vallen = 0;
166 				pairs[i].isnull = true;
167 			}
168 			else
169 			{
170 				pairs[i].val = PLyObject_AsString(value);
171 				pairs[i].vallen = hstoreCheckValLen(strlen(pairs[i].val));
172 				pairs[i].isnull = false;
173 			}
174 		}
175 		Py_DECREF(items);
176 
177 		pcount = hstoreUniquePairs(pairs, pcount, &buflen);
178 		out = hstorePairs(pairs, pcount, buflen);
179 	}
180 	PG_CATCH();
181 	{
182 		Py_DECREF(items);
183 		PG_RE_THROW();
184 	}
185 	PG_END_TRY();
186 
187 	PG_RETURN_POINTER(out);
188 }
189