dependency.h

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/*-------------------------------------------------------------------------
 *
 * dependency.h
 *    Routines to support inter-object dependencies.
 *
 *
 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/catalog/dependency.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef DEPENDENCY_H
#define DEPENDENCY_H
 
#include "catalog/objectaddress.h"
 
 
/*
 * Precise semantics of a dependency relationship are specified by the
 * DependencyType code (which is stored in a "char" field in pg_depend,
 * so we assign ASCII-code values to the enumeration members).
 *
 * In all cases, a dependency relationship indicates that the referenced
 * object may not be dropped without also dropping the dependent object.
 * However, there are several subflavors; see the description of pg_depend
 * in catalogs.sgml for details.
 */
 
typedef enum DependencyType
{
    DEPENDENCY_NORMAL = 'n',
    DEPENDENCY_AUTO = 'a',
    DEPENDENCY_INTERNAL = 'i',
    DEPENDENCY_PARTITION_PRI = 'P',
    DEPENDENCY_PARTITION_SEC = 'S',
    DEPENDENCY_EXTENSION = 'e',
    DEPENDENCY_AUTO_EXTENSION = 'x',
} DependencyType;
 
/*
 * There is also a SharedDependencyType enum type that determines the exact
 * semantics of an entry in pg_shdepend.  Just like regular dependency entries,
 * any pg_shdepend entry means that the referenced object cannot be dropped
 * unless the dependent object is dropped at the same time.  There are some
 * additional rules however:
 *
 * (a) a SHARED_DEPENDENCY_OWNER entry means that the referenced object is
 * the role owning the dependent object.  The referenced object must be
 * a pg_authid entry.
 *
 * (b) a SHARED_DEPENDENCY_ACL entry means that the referenced object is
 * a role mentioned in the ACL field of the dependent object.  The referenced
 * object must be a pg_authid entry.  (SHARED_DEPENDENCY_ACL entries are not
 * created for the owner of an object; hence two objects may be linked by
 * one or the other, but not both, of these dependency types.)
 *
 * (c) a SHARED_DEPENDENCY_INITACL entry means that the referenced object is
 * a role mentioned in a pg_init_privs entry for the dependent object.
 * The referenced object must be a pg_authid entry.  (Unlike the case for
 * SHARED_DEPENDENCY_ACL, we make an entry for such a role whether or not
 * it is the object's owner.)
 *
 * (d) a SHARED_DEPENDENCY_POLICY entry means that the referenced object is
 * a role mentioned in a policy object.  The referenced object must be a
 * pg_authid entry.
 *
 * (e) a SHARED_DEPENDENCY_TABLESPACE entry means that the referenced
 * object is a tablespace mentioned in a relation without storage.  The
 * referenced object must be a pg_tablespace entry.  (Relations that have
 * storage don't need this: they are protected by the existence of a physical
 * file in the tablespace.)
 *
 * SHARED_DEPENDENCY_INVALID is a value used as a parameter in internal
 * routines, and is not valid in the catalog itself.
 */
typedef enum SharedDependencyType
{
    SHARED_DEPENDENCY_OWNER = 'o',
    SHARED_DEPENDENCY_ACL = 'a',
    SHARED_DEPENDENCY_INITACL = 'i',
    SHARED_DEPENDENCY_POLICY = 'r',
    SHARED_DEPENDENCY_TABLESPACE = 't',
    SHARED_DEPENDENCY_INVALID = 0,
} SharedDependencyType;
 
/* expansible list of ObjectAddresses (private in dependency.c) */
typedef struct ObjectAddresses ObjectAddresses;
 
/* flag bits for performDeletion/performMultipleDeletions: */
#define PERFORM_DELETION_INTERNAL           0x0001  /* internal action */
#define PERFORM_DELETION_CONCURRENTLY       0x0002  /* concurrent drop */
#define PERFORM_DELETION_QUIETLY            0x0004  /* suppress notices */
#define PERFORM_DELETION_SKIP_ORIGINAL      0x0008  /* keep original obj */
#define PERFORM_DELETION_SKIP_EXTENSIONS    0x0010  /* keep extensions */
#define PERFORM_DELETION_CONCURRENT_LOCK    0x0020  /* normal drop with
                                                     * concurrent lock mode */
 
 
/* in dependency.c */
 
extern void AcquireDeletionLock(const ObjectAddress *object, int flags);
 
extern void ReleaseDeletionLock(const ObjectAddress *object);
 
extern void performDeletion(const ObjectAddress *object,
                            DropBehavior behavior, int flags);
 
extern void performMultipleDeletions(const ObjectAddresses *objects,
                                     DropBehavior behavior, int flags);
 
extern void recordDependencyOnExpr(const ObjectAddress *depender,
                                   Node *expr, List *rtable,
                                   DependencyType behavior);
 
extern void recordDependencyOnSingleRelExpr(const ObjectAddress *depender,
                                            Node *expr, Oid relId,
                                            DependencyType behavior,
                                            DependencyType self_behavior,
                                            bool reverse_self);
 
extern ObjectAddresses *new_object_addresses(void);
 
extern void add_exact_object_address(const ObjectAddress *object,
                                     ObjectAddresses *addrs);
 
extern bool object_address_present(const ObjectAddress *object,
                                   const ObjectAddresses *addrs);
 
extern void record_object_address_dependencies(const ObjectAddress *depender,
                                               ObjectAddresses *referenced,
                                               DependencyType behavior);
 
extern void sort_object_addresses(ObjectAddresses *addrs);
 
extern void free_object_addresses(ObjectAddresses *addrs);
 
/* in pg_depend.c */
 
extern void recordDependencyOn(const ObjectAddress *depender,
                               const ObjectAddress *referenced,
                               DependencyType behavior);
 
extern void recordMultipleDependencies(const ObjectAddress *depender,
                                       const ObjectAddress *referenced,
                                       int nreferenced,
                                       DependencyType behavior);
 
extern void recordDependencyOnCurrentExtension(const ObjectAddress *object,
                                               bool isReplace);
 
extern void checkMembershipInCurrentExtension(const ObjectAddress *object);
 
extern long deleteDependencyRecordsFor(Oid classId, Oid objectId,
                                       bool skipExtensionDeps);
 
extern long deleteDependencyRecordsForClass(Oid classId, Oid objectId,
                                            Oid refclassId, char deptype);
 
extern long deleteDependencyRecordsForSpecific(Oid classId, Oid objectId,
                                               char deptype,
                                               Oid refclassId, Oid refobjectId);
 
extern long changeDependencyFor(Oid classId, Oid objectId,
                                Oid refClassId, Oid oldRefObjectId,
                                Oid newRefObjectId);
 
extern long changeDependenciesOf(Oid classId, Oid oldObjectId,
                                 Oid newObjectId);
 
extern long changeDependenciesOn(Oid refClassId, Oid oldRefObjectId,
                                 Oid newRefObjectId);
 
extern Oid  getExtensionOfObject(Oid classId, Oid objectId);
extern List *getAutoExtensionsOfObject(Oid classId, Oid objectId);
 
extern bool sequenceIsOwned(Oid seqId, char deptype, Oid *tableId, int32 *colId);
extern List *getOwnedSequences(Oid relid);
extern Oid  getIdentitySequence(Relation rel, AttrNumber attnum, bool missing_ok);
 
extern Oid  get_index_constraint(Oid indexId);
 
extern List *get_index_ref_constraints(Oid indexId);
 
/* in pg_shdepend.c */
 
extern void recordSharedDependencyOn(ObjectAddress *depender,
                                     ObjectAddress *referenced,
                                     SharedDependencyType deptype);
 
extern void deleteSharedDependencyRecordsFor(Oid classId, Oid objectId,
                                             int32 objectSubId);
 
extern void recordDependencyOnOwner(Oid classId, Oid objectId, Oid owner);
 
extern void changeDependencyOnOwner(Oid classId, Oid objectId,
                                    Oid newOwnerId);
 
extern void recordDependencyOnTablespace(Oid classId, Oid objectId,
                                         Oid tablespace);
 
extern void changeDependencyOnTablespace(Oid classId, Oid objectId,
                                         Oid newTablespaceId);
 
extern void updateAclDependencies(Oid classId, Oid objectId, int32 objsubId,
                                  Oid ownerId,
                                  int noldmembers, Oid *oldmembers,
                                  int nnewmembers, Oid *newmembers);
 
extern void updateInitAclDependencies(Oid classId, Oid objectId, int32 objsubId,
                                      int noldmembers, Oid *oldmembers,
                                      int nnewmembers, Oid *newmembers);
 
extern bool checkSharedDependencies(Oid classId, Oid objectId,
                                    char **detail_msg, char **detail_log_msg);
 
extern void shdepLockAndCheckObject(Oid classId, Oid objectId);
 
extern void copyTemplateDependencies(Oid templateDbId, Oid newDbId);
 
extern void dropDatabaseDependencies(Oid databaseId);
 
extern void shdepDropOwned(List *roleids, DropBehavior behavior);
 
extern void shdepReassignOwned(List *roleids, Oid newrole);
 
#endif                          /* DEPENDENCY_H */