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pg_conversion.c
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_conversion.c
4  * routines to support manipulation of the pg_conversion relation
5  *
6  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/catalog/pg_conversion.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "access/heapam.h"
18 #include "access/htup_details.h"
19 #include "access/sysattr.h"
20 #include "catalog/dependency.h"
21 #include "catalog/indexing.h"
22 #include "catalog/objectaccess.h"
23 #include "catalog/pg_conversion.h"
25 #include "catalog/pg_namespace.h"
26 #include "catalog/pg_proc.h"
27 #include "mb/pg_wchar.h"
28 #include "utils/builtins.h"
29 #include "utils/catcache.h"
30 #include "utils/fmgroids.h"
31 #include "utils/rel.h"
32 #include "utils/syscache.h"
33 #include "utils/tqual.h"
34 
35 /*
36  * ConversionCreate
37  *
38  * Add a new tuple to pg_conversion.
39  */
41 ConversionCreate(const char *conname, Oid connamespace,
42  Oid conowner,
43  int32 conforencoding, int32 contoencoding,
44  Oid conproc, bool def)
45 {
46  int i;
47  Relation rel;
48  TupleDesc tupDesc;
49  HeapTuple tup;
50  bool nulls[Natts_pg_conversion];
53  ObjectAddress myself,
54  referenced;
55 
56  /* sanity checks */
57  if (!conname)
58  elog(ERROR, "no conversion name supplied");
59 
60  /* make sure there is no existing conversion of same name */
62  PointerGetDatum(conname),
63  ObjectIdGetDatum(connamespace)))
64  ereport(ERROR,
66  errmsg("conversion \"%s\" already exists", conname)));
67 
68  if (def)
69  {
70  /*
71  * make sure there is no existing default <for encoding><to encoding>
72  * pair in this name space
73  */
74  if (FindDefaultConversion(connamespace,
75  conforencoding,
76  contoencoding))
77  ereport(ERROR,
79  errmsg("default conversion for %s to %s already exists",
80  pg_encoding_to_char(conforencoding),
81  pg_encoding_to_char(contoencoding))));
82  }
83 
84  /* open pg_conversion */
86  tupDesc = rel->rd_att;
87 
88  /* initialize nulls and values */
89  for (i = 0; i < Natts_pg_conversion; i++)
90  {
91  nulls[i] = false;
92  values[i] = (Datum) NULL;
93  }
94 
95  /* form a tuple */
96  namestrcpy(&cname, conname);
97  values[Anum_pg_conversion_conname - 1] = NameGetDatum(&cname);
98  values[Anum_pg_conversion_connamespace - 1] = ObjectIdGetDatum(connamespace);
99  values[Anum_pg_conversion_conowner - 1] = ObjectIdGetDatum(conowner);
100  values[Anum_pg_conversion_conforencoding - 1] = Int32GetDatum(conforencoding);
101  values[Anum_pg_conversion_contoencoding - 1] = Int32GetDatum(contoencoding);
102  values[Anum_pg_conversion_conproc - 1] = ObjectIdGetDatum(conproc);
103  values[Anum_pg_conversion_condefault - 1] = BoolGetDatum(def);
104 
105  tup = heap_form_tuple(tupDesc, values, nulls);
106 
107  /* insert a new tuple */
108  CatalogTupleInsert(rel, tup);
109 
110  myself.classId = ConversionRelationId;
111  myself.objectId = HeapTupleGetOid(tup);
112  myself.objectSubId = 0;
113 
114  /* create dependency on conversion procedure */
115  referenced.classId = ProcedureRelationId;
116  referenced.objectId = conproc;
117  referenced.objectSubId = 0;
118  recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
119 
120  /* create dependency on namespace */
121  referenced.classId = NamespaceRelationId;
122  referenced.objectId = connamespace;
123  referenced.objectSubId = 0;
124  recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
125 
126  /* create dependency on owner */
128  conowner);
129 
130  /* dependency on extension */
131  recordDependencyOnCurrentExtension(&myself, false);
132 
133  /* Post creation hook for new conversion */
135 
136  heap_freetuple(tup);
138 
139  return myself;
140 }
141 
142 /*
143  * RemoveConversionById
144  *
145  * Remove a tuple from pg_conversion by Oid. This function is solely
146  * called inside catalog/dependency.c
147  */
148 void
149 RemoveConversionById(Oid conversionOid)
150 {
151  Relation rel;
152  HeapTuple tuple;
153  HeapScanDesc scan;
154  ScanKeyData scanKeyData;
155 
156  ScanKeyInit(&scanKeyData,
158  BTEqualStrategyNumber, F_OIDEQ,
159  ObjectIdGetDatum(conversionOid));
160 
161  /* open pg_conversion */
163 
164  scan = heap_beginscan_catalog(rel, 1, &scanKeyData);
165 
166  /* search for the target tuple */
168  CatalogTupleDelete(rel, &tuple->t_self);
169  else
170  elog(ERROR, "could not find tuple for conversion %u", conversionOid);
171  heap_endscan(scan);
173 }
174 
175 /*
176  * FindDefaultConversion
177  *
178  * Find "default" conversion proc by for_encoding and to_encoding in the
179  * given namespace.
180  *
181  * If found, returns the procedure's oid, otherwise InvalidOid. Note that
182  * you get the procedure's OID not the conversion's OID!
183  */
184 Oid
185 FindDefaultConversion(Oid name_space, int32 for_encoding, int32 to_encoding)
186 {
187  CatCList *catlist;
188  HeapTuple tuple;
189  Form_pg_conversion body;
190  Oid proc = InvalidOid;
191  int i;
192 
194  ObjectIdGetDatum(name_space),
195  Int32GetDatum(for_encoding),
196  Int32GetDatum(to_encoding));
197 
198  for (i = 0; i < catlist->n_members; i++)
199  {
200  tuple = &catlist->members[i]->tuple;
201  body = (Form_pg_conversion) GETSTRUCT(tuple);
202  if (body->condefault)
203  {
204  proc = body->conproc;
205  break;
206  }
207  }
208  ReleaseSysCacheList(catlist);
209  return proc;
210 }
#define NamespaceRelationId
Definition: pg_namespace.h:34
#define NameGetDatum(X)
Definition: postgres.h:601
int n_members
Definition: catcache.h:154
#define GETSTRUCT(TUP)
Definition: htup_details.h:656
void heap_endscan(HeapScanDesc scan)
Definition: heapam.c:1578
#define InvokeObjectPostCreateHook(classId, objectId, subId)
Definition: objectaccess.h:145
#define Anum_pg_conversion_condefault
Definition: pg_conversion.h:70
#define ObjectIdAttributeNumber
Definition: sysattr.h:22
#define PointerGetDatum(X)
Definition: postgres.h:562
#define ProcedureRelationId
Definition: pg_proc.h:33
#define Anum_pg_conversion_contoencoding
Definition: pg_conversion.h:68
int errcode(int sqlerrcode)
Definition: elog.c:575
#define Natts_pg_conversion
Definition: pg_conversion.h:63
void CatalogTupleDelete(Relation heapRel, ItemPointer tid)
Definition: indexing.c:255
void recordDependencyOn(const ObjectAddress *depender, const ObjectAddress *referenced, DependencyType behavior)
Definition: pg_depend.c:44
HeapTuple heap_form_tuple(TupleDesc tupleDescriptor, Datum *values, bool *isnull)
Definition: heaptuple.c:692
#define heap_close(r, l)
Definition: heapam.h:97
void recordDependencyOnOwner(Oid classId, Oid objectId, Oid owner)
Definition: pg_shdepend.c:159
void heap_freetuple(HeapTuple htup)
Definition: heaptuple.c:1372
unsigned int Oid
Definition: postgres_ext.h:31
int namestrcpy(Name name, const char *str)
Definition: name.c:217
void RemoveConversionById(Oid conversionOid)
signed int int32
Definition: c.h:256
CatCTup * members[FLEXIBLE_ARRAY_MEMBER]
Definition: catcache.h:155
#define Anum_pg_conversion_conforencoding
Definition: pg_conversion.h:67
#define ObjectIdGetDatum(X)
Definition: postgres.h:513
#define ERROR
Definition: elog.h:43
Oid CatalogTupleInsert(Relation heapRel, HeapTuple tup)
Definition: indexing.c:162
ItemPointerData t_self
Definition: htup.h:65
Definition: c.h:493
#define RowExclusiveLock
Definition: lockdefs.h:38
HeapScanDesc heap_beginscan_catalog(Relation relation, int nkeys, ScanKey key)
Definition: heapam.c:1399
#define ereport(elevel, rest)
Definition: elog.h:122
#define ReleaseSysCacheList(x)
Definition: syscache.h:210
ObjectAddress ConversionCreate(const char *conname, Oid connamespace, Oid conowner, int32 conforencoding, int32 contoencoding, Oid conproc, bool def)
Definition: pg_conversion.c:41
uintptr_t Datum
Definition: postgres.h:372
FormData_pg_conversion * Form_pg_conversion
Definition: pg_conversion.h:56
HeapTuple heap_getnext(HeapScanDesc scan, ScanDirection direction)
Definition: heapam.c:1794
Relation heap_open(Oid relationId, LOCKMODE lockmode)
Definition: heapam.c:1284
TupleDesc rd_att
Definition: rel.h:115
#define BoolGetDatum(X)
Definition: postgres.h:408
#define InvalidOid
Definition: postgres_ext.h:36
const char * pg_encoding_to_char(int encoding)
Definition: encnames.c:607
#define HeapTupleIsValid(tuple)
Definition: htup.h:77
#define NULL
Definition: c.h:229
#define Anum_pg_conversion_conowner
Definition: pg_conversion.h:66
void recordDependencyOnCurrentExtension(const ObjectAddress *object, bool isReplace)
Definition: pg_depend.c:139
#define SearchSysCacheExists2(cacheId, key1, key2)
Definition: syscache.h:176
#define Anum_pg_conversion_conname
Definition: pg_conversion.h:64
static Datum values[MAXATTR]
Definition: bootstrap.c:163
#define Int32GetDatum(X)
Definition: postgres.h:485
int errmsg(const char *fmt,...)
Definition: elog.c:797
#define SearchSysCacheList3(cacheId, key1, key2, key3)
Definition: syscache.h:205
int i
void ScanKeyInit(ScanKey entry, AttrNumber attributeNumber, StrategyNumber strategy, RegProcedure procedure, Datum argument)
Definition: scankey.c:76
#define Anum_pg_conversion_conproc
Definition: pg_conversion.h:69
HeapTupleData tuple
Definition: catcache.h:116
#define elog
Definition: elog.h:219
Oid FindDefaultConversion(Oid name_space, int32 for_encoding, int32 to_encoding)
#define HeapTupleGetOid(tuple)
Definition: htup_details.h:695
#define Anum_pg_conversion_connamespace
Definition: pg_conversion.h:65
#define ERRCODE_DUPLICATE_OBJECT
Definition: streamutil.c:31
#define ConversionRelationId
Definition: pg_conversion.h:38
#define BTEqualStrategyNumber
Definition: stratnum.h:31