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pg_type.h
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_type.h
4  * definition of the "type" system catalog (pg_type)
5  *
6  *
7  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/catalog/pg_type.h
11  *
12  * NOTES
13  * The Catalog.pm module reads this file and derives schema
14  * information.
15  *
16  *-------------------------------------------------------------------------
17  */
18 #ifndef PG_TYPE_H
19 #define PG_TYPE_H
20 
21 #include "catalog/genbki.h"
22 #include "catalog/pg_type_d.h"
23 
24 #include "catalog/objectaddress.h"
25 #include "nodes/nodes.h"
26 
27 /* ----------------
28  * pg_type definition. cpp turns this into
29  * typedef struct FormData_pg_type
30  *
31  * Some of the values in a pg_type instance are copied into
32  * pg_attribute instances. Some parts of Postgres use the pg_type copy,
33  * while others use the pg_attribute copy, so they must match.
34  * See struct FormData_pg_attribute for details.
35  * ----------------
36  */
37 CATALOG(pg_type,1247,TypeRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(71,TypeRelation_Rowtype_Id) BKI_SCHEMA_MACRO
38 {
39  Oid oid; /* oid */
40 
41  /* type name */
43 
44  /* OID of namespace containing this type */
45  Oid typnamespace BKI_DEFAULT(PGNSP);
46 
47  /* type owner */
48  Oid typowner BKI_DEFAULT(PGUID);
49 
50  /*
51  * For a fixed-size type, typlen is the number of bytes we use to
52  * represent a value of this type, e.g. 4 for an int4. But for a
53  * variable-length type, typlen is negative. We use -1 to indicate a
54  * "varlena" type (one that has a length word), -2 to indicate a
55  * null-terminated C string.
56  */
57  int16 typlen BKI_ARRAY_DEFAULT(-1);
58 
59  /*
60  * typbyval determines whether internal Postgres routines pass a value of
61  * this type by value or by reference. typbyval had better be false if
62  * the length is not 1, 2, or 4 (or 8 on 8-byte-Datum machines).
63  * Variable-length types are always passed by reference. Note that
64  * typbyval can be false even if the length would allow pass-by-value; for
65  * example, type macaddr8 is pass-by-ref even when Datum is 8 bytes.
66  */
67  bool typbyval BKI_ARRAY_DEFAULT(f);
68 
69  /*
70  * typtype is 'b' for a base type, 'c' for a composite type (e.g., a
71  * table's rowtype), 'd' for a domain, 'e' for an enum type, 'p' for a
72  * pseudo-type, or 'r' for a range type. (Use the TYPTYPE macros below.)
73  *
74  * If typtype is 'c', typrelid is the OID of the class' entry in pg_class.
75  */
76  char typtype BKI_DEFAULT(b) BKI_ARRAY_DEFAULT(b);
77 
78  /*
79  * typcategory and typispreferred help the parser distinguish preferred
80  * and non-preferred coercions. The category can be any single ASCII
81  * character (but not \0). The categories used for built-in types are
82  * identified by the TYPCATEGORY macros below.
83  */
84 
85  /* arbitrary type classification */
86  char typcategory BKI_ARRAY_DEFAULT(A);
87 
88  /* is type "preferred" within its category? */
89  bool typispreferred BKI_DEFAULT(f) BKI_ARRAY_DEFAULT(f);
90 
91  /*
92  * If typisdefined is false, the entry is only a placeholder (forward
93  * reference). We know the type's name and owner, but not yet anything
94  * else about it.
95  */
96  bool typisdefined BKI_DEFAULT(t);
97 
98  /* delimiter for arrays of this type */
99  char typdelim BKI_DEFAULT(',');
100 
101  /* associated pg_class OID if a composite type, else 0 */
102  Oid typrelid BKI_DEFAULT(0) BKI_ARRAY_DEFAULT(0) BKI_LOOKUP(pg_class);
103 
104  /*
105  * If typelem is not 0 then it identifies another row in pg_type. The
106  * current type can then be subscripted like an array yielding values of
107  * type typelem. A non-zero typelem does not guarantee this type to be a
108  * "real" array type; some ordinary fixed-length types can also be
109  * subscripted (e.g., name, point). Variable-length types can *not* be
110  * turned into pseudo-arrays like that. Hence, the way to determine
111  * whether a type is a "true" array type is if:
112  *
113  * typelem != 0 and typlen == -1.
114  */
115  Oid typelem BKI_DEFAULT(0) BKI_LOOKUP(pg_type);
116 
117  /*
118  * If there is a "true" array type having this type as element type,
119  * typarray links to it. Zero if no associated "true" array type.
120  */
121  Oid typarray BKI_DEFAULT(0) BKI_ARRAY_DEFAULT(0) BKI_LOOKUP(pg_type);
122 
123  /*
124  * I/O conversion procedures for the datatype.
125  */
126 
127  /* text format (required) */
128  regproc typinput BKI_ARRAY_DEFAULT(array_in) BKI_LOOKUP(pg_proc);
129  regproc typoutput BKI_ARRAY_DEFAULT(array_out) BKI_LOOKUP(pg_proc);
130 
131  /* binary format (optional) */
132  regproc typreceive BKI_ARRAY_DEFAULT(array_recv) BKI_LOOKUP(pg_proc);
134 
135  /*
136  * I/O functions for optional type modifiers.
137  */
138  regproc typmodin BKI_DEFAULT(-) BKI_LOOKUP(pg_proc);
139  regproc typmodout BKI_DEFAULT(-) BKI_LOOKUP(pg_proc);
140 
141  /*
142  * Custom ANALYZE procedure for the datatype (0 selects the default).
143  */
145 
146  /* ----------------
147  * typalign is the alignment required when storing a value of this
148  * type. It applies to storage on disk as well as most
149  * representations of the value inside Postgres. When multiple values
150  * are stored consecutively, such as in the representation of a
151  * complete row on disk, padding is inserted before a datum of this
152  * type so that it begins on the specified boundary. The alignment
153  * reference is the beginning of the first datum in the sequence.
154  *
155  * 'c' = CHAR alignment, ie no alignment needed.
156  * 's' = SHORT alignment (2 bytes on most machines).
157  * 'i' = INT alignment (4 bytes on most machines).
158  * 'd' = DOUBLE alignment (8 bytes on many machines, but by no means all).
159  *
160  * See include/access/tupmacs.h for the macros that compute these
161  * alignment requirements. Note also that we allow the nominal alignment
162  * to be violated when storing "packed" varlenas; the TOAST mechanism
163  * takes care of hiding that from most code.
164  *
165  * NOTE: for types used in system tables, it is critical that the
166  * size and alignment defined in pg_type agree with the way that the
167  * compiler will lay out the field in a struct representing a table row.
168  * ----------------
169  */
170  char typalign;
171 
172  /* ----------------
173  * typstorage tells if the type is prepared for toasting and what
174  * the default strategy for attributes of this type should be.
175  *
176  * 'p' PLAIN type not prepared for toasting
177  * 'e' EXTERNAL external storage possible, don't try to compress
178  * 'x' EXTENDED try to compress and store external if required
179  * 'm' MAIN like 'x' but try to keep in main tuple
180  * ----------------
181  */
182  char typstorage BKI_DEFAULT(p) BKI_ARRAY_DEFAULT(x);
183 
184  /*
185  * This flag represents a "NOT NULL" constraint against this datatype.
186  *
187  * If true, the attnotnull column for a corresponding table column using
188  * this datatype will always enforce the NOT NULL constraint.
189  *
190  * Used primarily for domain types.
191  */
192  bool typnotnull BKI_DEFAULT(f);
193 
194  /*
195  * Domains use typbasetype to show the base (or domain) type that the
196  * domain is based on. Zero if the type is not a domain.
197  */
198  Oid typbasetype BKI_DEFAULT(0);
199 
200  /*
201  * Domains use typtypmod to record the typmod to be applied to their base
202  * type (-1 if base type does not use a typmod). -1 if this type is not a
203  * domain.
204  */
205  int32 typtypmod BKI_DEFAULT(-1);
206 
207  /*
208  * typndims is the declared number of dimensions for an array domain type
209  * (i.e., typbasetype is an array type). Otherwise zero.
210  */
211  int32 typndims BKI_DEFAULT(0);
212 
213  /*
214  * Collation: 0 if type cannot use collations, nonzero (typically
215  * DEFAULT_COLLATION_OID) for collatable base types, possibly some other
216  * OID for domains over collatable types
217  */
218  Oid typcollation BKI_DEFAULT(0) BKI_LOOKUP(pg_collation);
219 
220 #ifdef CATALOG_VARLEN /* variable-length fields start here */
221 
222  /*
223  * If typdefaultbin is not NULL, it is the nodeToString representation of
224  * a default expression for the type. Currently this is only used for
225  * domains.
226  */
227  pg_node_tree typdefaultbin BKI_DEFAULT(_null_) BKI_ARRAY_DEFAULT(_null_);
228 
229  /*
230  * typdefault is NULL if the type has no associated default value. If
231  * typdefaultbin is not NULL, typdefault must contain a human-readable
232  * version of the default expression represented by typdefaultbin. If
233  * typdefaultbin is NULL and typdefault is not, then typdefault is the
234  * external representation of the type's default value, which may be fed
235  * to the type's input converter to produce a constant.
236  */
237  text typdefault BKI_DEFAULT(_null_) BKI_ARRAY_DEFAULT(_null_);
238 
239  /*
240  * Access permissions
241  */
242  aclitem typacl[1] BKI_DEFAULT(_null_);
243 #endif
245 
246 /* ----------------
247  * Form_pg_type corresponds to a pointer to a row with
248  * the format of pg_type relation.
249  * ----------------
250  */
252 
253 #ifdef EXPOSE_TO_CLIENT_CODE
254 
255 /*
256  * macros for values of poor-mans-enumerated-type columns
257  */
258 #define TYPTYPE_BASE 'b' /* base type (ordinary scalar type) */
259 #define TYPTYPE_COMPOSITE 'c' /* composite (e.g., table's rowtype) */
260 #define TYPTYPE_DOMAIN 'd' /* domain over another type */
261 #define TYPTYPE_ENUM 'e' /* enumerated type */
262 #define TYPTYPE_PSEUDO 'p' /* pseudo-type */
263 #define TYPTYPE_RANGE 'r' /* range type */
264 
265 #define TYPCATEGORY_INVALID '\0' /* not an allowed category */
266 #define TYPCATEGORY_ARRAY 'A'
267 #define TYPCATEGORY_BOOLEAN 'B'
268 #define TYPCATEGORY_COMPOSITE 'C'
269 #define TYPCATEGORY_DATETIME 'D'
270 #define TYPCATEGORY_ENUM 'E'
271 #define TYPCATEGORY_GEOMETRIC 'G'
272 #define TYPCATEGORY_NETWORK 'I' /* think INET */
273 #define TYPCATEGORY_NUMERIC 'N'
274 #define TYPCATEGORY_PSEUDOTYPE 'P'
275 #define TYPCATEGORY_RANGE 'R'
276 #define TYPCATEGORY_STRING 'S'
277 #define TYPCATEGORY_TIMESPAN 'T'
278 #define TYPCATEGORY_USER 'U'
279 #define TYPCATEGORY_BITSTRING 'V' /* er ... "varbit"? */
280 #define TYPCATEGORY_UNKNOWN 'X'
281 
282 /* Is a type OID a polymorphic pseudotype? (Beware of multiple evaluation) */
283 #define IsPolymorphicType(typid) \
284  ((typid) == ANYELEMENTOID || \
285  (typid) == ANYARRAYOID || \
286  (typid) == ANYNONARRAYOID || \
287  (typid) == ANYENUMOID || \
288  (typid) == ANYRANGEOID)
289 
290 #endif /* EXPOSE_TO_CLIENT_CODE */
291 
292 
293 extern ObjectAddress TypeShellMake(const char *typeName,
294  Oid typeNamespace,
295  Oid ownerId);
296 
297 extern ObjectAddress TypeCreate(Oid newTypeOid,
298  const char *typeName,
299  Oid typeNamespace,
300  Oid relationOid,
301  char relationKind,
302  Oid ownerId,
303  int16 internalSize,
304  char typeType,
305  char typeCategory,
306  bool typePreferred,
307  char typDelim,
308  Oid inputProcedure,
309  Oid outputProcedure,
310  Oid receiveProcedure,
311  Oid sendProcedure,
312  Oid typmodinProcedure,
313  Oid typmodoutProcedure,
314  Oid analyzeProcedure,
315  Oid elementType,
316  bool isImplicitArray,
317  Oid arrayType,
318  Oid baseType,
319  const char *defaultTypeValue,
320  char *defaultTypeBin,
321  bool passedByValue,
322  char alignment,
323  char storage,
324  int32 typeMod,
325  int32 typNDims,
326  bool typeNotNull,
327  Oid typeCollation);
328 
329 extern void GenerateTypeDependencies(Oid typeObjectId,
330  Form_pg_type typeForm,
331  Node *defaultExpr,
332  void *typacl,
333  char relationKind, /* only for relation
334  * rowtypes */
335  bool isImplicitArray,
336  bool isDependentType,
337  bool rebuild);
338 
339 extern void RenameTypeInternal(Oid typeOid, const char *newTypeName,
340  Oid typeNamespace);
341 
342 extern char *makeArrayTypeName(const char *typeName, Oid typeNamespace);
343 
344 extern bool moveArrayTypeName(Oid typeOid, const char *typeName,
345  Oid typeNamespace);
346 
347 #endif /* PG_TYPE_H */
#define BKI_BOOTSTRAP
Definition: genbki.h:26
signed short int16
Definition: c.h:345
Datum array_send(PG_FUNCTION_ARGS)
Definition: arrayfuncs.c:1547
Oid typnamespace BKI_DEFAULT(PGNSP)
Definition: nodes.h:525
bool moveArrayTypeName(Oid typeOid, const char *typeName, Oid typeNamespace)
Definition: pg_type.c:850
Datum array_recv(PG_FUNCTION_ARGS)
Definition: arrayfuncs.c:1267
int16 typlen BKI_ARRAY_DEFAULT(-1)
unsigned int Oid
Definition: postgres_ext.h:31
Datum array_out(PG_FUNCTION_ARGS)
Definition: arrayfuncs.c:1012
signed int int32
Definition: c.h:346
FormData_pg_type
Definition: pg_type.h:244
void GenerateTypeDependencies(Oid typeObjectId, Form_pg_type typeForm, Node *defaultExpr, void *typacl, char relationKind, bool isImplicitArray, bool isDependentType, bool rebuild)
Definition: pg_type.c:537
void RenameTypeInternal(Oid typeOid, const char *newTypeName, Oid typeNamespace)
Definition: pg_type.c:709
char typalign
Definition: pg_type.h:170
Definition: c.h:603
char * makeArrayTypeName(const char *typeName, Oid typeNamespace)
Definition: pg_type.c:784
#define BKI_LOOKUP(catalog)
Definition: genbki.h:42
NameData typname
Definition: pg_type.h:42
Datum array_typanalyze(PG_FUNCTION_ARGS)
#define BKI_ROWTYPE_OID(oid, oidmacro)
Definition: genbki.h:28
ObjectAddress TypeCreate(Oid newTypeOid, const char *typeName, Oid typeNamespace, Oid relationOid, char relationKind, Oid ownerId, int16 internalSize, char typeType, char typeCategory, bool typePreferred, char typDelim, Oid inputProcedure, Oid outputProcedure, Oid receiveProcedure, Oid sendProcedure, Oid typmodinProcedure, Oid typmodoutProcedure, Oid analyzeProcedure, Oid elementType, bool isImplicitArray, Oid arrayType, Oid baseType, const char *defaultTypeValue, char *defaultTypeBin, bool passedByValue, char alignment, char storage, int32 typeMod, int32 typNDims, bool typeNotNull, Oid typeCollation)
Definition: pg_type.c:192
TypeRelation_Rowtype_Id BKI_SCHEMA_MACRO
Definition: pg_type.h:38
ObjectAddress TypeShellMake(const char *typeName, Oid typeNamespace, Oid ownerId)
Definition: pg_type.c:56
FormData_pg_type * Form_pg_type
Definition: pg_type.h:251
Oid regproc
Definition: c.h:504
Definition: c.h:549
Datum array_in(PG_FUNCTION_ARGS)
Definition: arrayfuncs.c:172
CATALOG(pg_type, 1247, TypeRelationId) BKI_BOOTSTRAP BKI_ROWTYPE_OID(71