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pg_collation.c
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_collation.c
4  * routines to support manipulation of the pg_collation relation
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/catalog/pg_collation.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "access/htup_details.h"
18 #include "access/table.h"
19 #include "catalog/catalog.h"
20 #include "catalog/dependency.h"
21 #include "catalog/indexing.h"
22 #include "catalog/objectaccess.h"
23 #include "catalog/pg_collation.h"
24 #include "catalog/pg_namespace.h"
25 #include "mb/pg_wchar.h"
26 #include "utils/builtins.h"
27 #include "utils/rel.h"
28 #include "utils/syscache.h"
29 
30 
31 /*
32  * CollationCreate
33  *
34  * Add a new tuple to pg_collation.
35  *
36  * if_not_exists: if true, don't fail on duplicate name, just print a notice
37  * and return InvalidOid.
38  * quiet: if true, don't fail on duplicate name, just silently return
39  * InvalidOid (overrides if_not_exists).
40  */
41 Oid
42 CollationCreate(const char *collname, Oid collnamespace,
43  Oid collowner,
44  char collprovider,
45  bool collisdeterministic,
46  int32 collencoding,
47  const char *collcollate, const char *collctype,
48  const char *colllocale,
49  const char *collicurules,
50  const char *collversion,
51  bool if_not_exists,
52  bool quiet)
53 {
54  Relation rel;
55  TupleDesc tupDesc;
56  HeapTuple tup;
57  Datum values[Natts_pg_collation];
58  bool nulls[Natts_pg_collation];
59  NameData name_name;
60  Oid oid;
61  ObjectAddress myself,
62  referenced;
63 
64  Assert(collname);
65  Assert(collnamespace);
66  Assert(collowner);
67  Assert((collprovider == COLLPROVIDER_LIBC &&
68  collcollate && collctype && !colllocale) ||
69  (collprovider != COLLPROVIDER_LIBC &&
70  !collcollate && !collctype && colllocale));
71 
72  /*
73  * Make sure there is no existing collation of same name & encoding.
74  *
75  * This would be caught by the unique index anyway; we're just giving a
76  * friendlier error message. The unique index provides a backstop against
77  * race conditions.
78  */
79  oid = GetSysCacheOid3(COLLNAMEENCNSP,
80  Anum_pg_collation_oid,
81  PointerGetDatum(collname),
82  Int32GetDatum(collencoding),
83  ObjectIdGetDatum(collnamespace));
84  if (OidIsValid(oid))
85  {
86  if (quiet)
87  return InvalidOid;
88  else if (if_not_exists)
89  {
90  /*
91  * If we are in an extension script, insist that the pre-existing
92  * object be a member of the extension, to avoid security risks.
93  */
94  ObjectAddressSet(myself, CollationRelationId, oid);
96 
97  /* OK to skip */
100  collencoding == -1
101  ? errmsg("collation \"%s\" already exists, skipping",
102  collname)
103  : errmsg("collation \"%s\" for encoding \"%s\" already exists, skipping",
104  collname, pg_encoding_to_char(collencoding))));
105  return InvalidOid;
106  }
107  else
108  ereport(ERROR,
110  collencoding == -1
111  ? errmsg("collation \"%s\" already exists",
112  collname)
113  : errmsg("collation \"%s\" for encoding \"%s\" already exists",
114  collname, pg_encoding_to_char(collencoding))));
115  }
116 
117  /* open pg_collation; see below about the lock level */
118  rel = table_open(CollationRelationId, ShareRowExclusiveLock);
119 
120  /*
121  * Also forbid a specific-encoding collation shadowing an any-encoding
122  * collation, or an any-encoding collation being shadowed (see
123  * get_collation_name()). This test is not backed up by the unique index,
124  * so we take a ShareRowExclusiveLock earlier, to protect against
125  * concurrent changes fooling this check.
126  */
127  if (collencoding == -1)
128  oid = GetSysCacheOid3(COLLNAMEENCNSP,
129  Anum_pg_collation_oid,
130  PointerGetDatum(collname),
132  ObjectIdGetDatum(collnamespace));
133  else
134  oid = GetSysCacheOid3(COLLNAMEENCNSP,
135  Anum_pg_collation_oid,
136  PointerGetDatum(collname),
137  Int32GetDatum(-1),
138  ObjectIdGetDatum(collnamespace));
139  if (OidIsValid(oid))
140  {
141  if (quiet)
142  {
143  table_close(rel, NoLock);
144  return InvalidOid;
145  }
146  else if (if_not_exists)
147  {
148  /*
149  * If we are in an extension script, insist that the pre-existing
150  * object be a member of the extension, to avoid security risks.
151  */
152  ObjectAddressSet(myself, CollationRelationId, oid);
154 
155  /* OK to skip */
156  table_close(rel, NoLock);
157  ereport(NOTICE,
159  errmsg("collation \"%s\" already exists, skipping",
160  collname)));
161  return InvalidOid;
162  }
163  else
164  ereport(ERROR,
166  errmsg("collation \"%s\" already exists",
167  collname)));
168  }
169 
170  tupDesc = RelationGetDescr(rel);
171 
172  /* form a tuple */
173  memset(nulls, 0, sizeof(nulls));
174 
175  namestrcpy(&name_name, collname);
176  oid = GetNewOidWithIndex(rel, CollationOidIndexId,
177  Anum_pg_collation_oid);
178  values[Anum_pg_collation_oid - 1] = ObjectIdGetDatum(oid);
179  values[Anum_pg_collation_collname - 1] = NameGetDatum(&name_name);
180  values[Anum_pg_collation_collnamespace - 1] = ObjectIdGetDatum(collnamespace);
181  values[Anum_pg_collation_collowner - 1] = ObjectIdGetDatum(collowner);
182  values[Anum_pg_collation_collprovider - 1] = CharGetDatum(collprovider);
183  values[Anum_pg_collation_collisdeterministic - 1] = BoolGetDatum(collisdeterministic);
184  values[Anum_pg_collation_collencoding - 1] = Int32GetDatum(collencoding);
185  if (collcollate)
186  values[Anum_pg_collation_collcollate - 1] = CStringGetTextDatum(collcollate);
187  else
188  nulls[Anum_pg_collation_collcollate - 1] = true;
189  if (collctype)
190  values[Anum_pg_collation_collctype - 1] = CStringGetTextDatum(collctype);
191  else
192  nulls[Anum_pg_collation_collctype - 1] = true;
193  if (colllocale)
194  values[Anum_pg_collation_colllocale - 1] = CStringGetTextDatum(colllocale);
195  else
196  nulls[Anum_pg_collation_colllocale - 1] = true;
197  if (collicurules)
198  values[Anum_pg_collation_collicurules - 1] = CStringGetTextDatum(collicurules);
199  else
200  nulls[Anum_pg_collation_collicurules - 1] = true;
201  if (collversion)
202  values[Anum_pg_collation_collversion - 1] = CStringGetTextDatum(collversion);
203  else
204  nulls[Anum_pg_collation_collversion - 1] = true;
205 
206  tup = heap_form_tuple(tupDesc, values, nulls);
207 
208  /* insert a new tuple */
209  CatalogTupleInsert(rel, tup);
210  Assert(OidIsValid(oid));
211 
212  /* set up dependencies for the new collation */
213  myself.classId = CollationRelationId;
214  myself.objectId = oid;
215  myself.objectSubId = 0;
216 
217  /* create dependency on namespace */
218  referenced.classId = NamespaceRelationId;
219  referenced.objectId = collnamespace;
220  referenced.objectSubId = 0;
221  recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
222 
223  /* create dependency on owner */
224  recordDependencyOnOwner(CollationRelationId, oid, collowner);
225 
226  /* dependency on extension */
227  recordDependencyOnCurrentExtension(&myself, false);
228 
229  /* Post creation hook for new collation */
230  InvokeObjectPostCreateHook(CollationRelationId, oid, 0);
231 
232  heap_freetuple(tup);
233  table_close(rel, NoLock);
234 
235  return oid;
236 }
static Datum values[MAXATTR]
Definition: bootstrap.c:152
#define CStringGetTextDatum(s)
Definition: builtins.h:97
signed int int32
Definition: c.h:494
#define Assert(condition)
Definition: c.h:858
#define OidIsValid(objectId)
Definition: c.h:775
Oid GetNewOidWithIndex(Relation relation, Oid indexId, AttrNumber oidcolumn)
Definition: catalog.c:391
@ DEPENDENCY_NORMAL
Definition: dependency.h:33
int errcode(int sqlerrcode)
Definition: elog.c:857
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define ERROR
Definition: elog.h:39
#define NOTICE
Definition: elog.h:35
#define ereport(elevel,...)
Definition: elog.h:149
HeapTuple heap_form_tuple(TupleDesc tupleDescriptor, const Datum *values, const bool *isnull)
Definition: heaptuple.c:1116
void heap_freetuple(HeapTuple htup)
Definition: heaptuple.c:1434
void CatalogTupleInsert(Relation heapRel, HeapTuple tup)
Definition: indexing.c:233
#define NoLock
Definition: lockdefs.h:34
#define ShareRowExclusiveLock
Definition: lockdefs.h:41
int GetDatabaseEncoding(void)
Definition: mbutils.c:1261
void namestrcpy(Name name, const char *str)
Definition: name.c:233
#define InvokeObjectPostCreateHook(classId, objectId, subId)
Definition: objectaccess.h:173
#define ObjectAddressSet(addr, class_id, object_id)
Definition: objectaddress.h:40
Oid CollationCreate(const char *collname, Oid collnamespace, Oid collowner, char collprovider, bool collisdeterministic, int32 collencoding, const char *collcollate, const char *collctype, const char *colllocale, const char *collicurules, const char *collversion, bool if_not_exists, bool quiet)
Definition: pg_collation.c:42
void checkMembershipInCurrentExtension(const ObjectAddress *object)
Definition: pg_depend.c:259
void recordDependencyOn(const ObjectAddress *depender, const ObjectAddress *referenced, DependencyType behavior)
Definition: pg_depend.c:46
void recordDependencyOnCurrentExtension(const ObjectAddress *object, bool isReplace)
Definition: pg_depend.c:194
void recordDependencyOnOwner(Oid classId, Oid objectId, Oid owner)
Definition: pg_shdepend.c:165
#define pg_encoding_to_char
Definition: pg_wchar.h:630
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
uintptr_t Datum
Definition: postgres.h:64
static Datum BoolGetDatum(bool X)
Definition: postgres.h:102
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:252
static Datum NameGetDatum(const NameData *X)
Definition: postgres.h:373
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:212
static Datum CharGetDatum(char X)
Definition: postgres.h:122
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
#define RelationGetDescr(relation)
Definition: rel.h:531
#define ERRCODE_DUPLICATE_OBJECT
Definition: streamutil.c:32
Definition: c.h:741
#define GetSysCacheOid3(cacheId, oidcol, key1, key2, key3)
Definition: syscache.h:108
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:40