codekingpro/portable-devtools

1/*-------------------------------------------------------------------------2 *3 * dsm.h4 *	  manage dynamic shared memory segments5 *6 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group7 * Portions Copyright (c) 1994, Regents of the University of California8 *9 * src/include/storage/dsm.h10 *11 *-------------------------------------------------------------------------12 */13#ifndef DSM_H14#define DSM_H15 16#include "storage/dsm_impl.h"17 18typedef struct dsm_segment dsm_segment;19 20#define DSM_CREATE_NULL_IF_MAXSEGMENTS			0x000121 22/* Startup and shutdown functions. */23struct PGShmemHeader;			/* avoid including pg_shmem.h */24extern void dsm_cleanup_using_control_segment(dsm_handle old_control_handle);25extern void dsm_postmaster_startup(struct PGShmemHeader *);26extern void dsm_backend_shutdown(void);27extern void dsm_detach_all(void);28 29extern size_t dsm_estimate_size(void);30extern void dsm_shmem_init(void);31 32#ifdef EXEC_BACKEND33extern void dsm_set_control_handle(dsm_handle h);34#endif35 36/* Functions that create or remove mappings. */37extern dsm_segment *dsm_create(Size size, int flags);38extern dsm_segment *dsm_attach(dsm_handle h);39extern void dsm_detach(dsm_segment *seg);40 41/* Resource management functions. */42extern void dsm_pin_mapping(dsm_segment *seg);43extern void dsm_unpin_mapping(dsm_segment *seg);44extern void dsm_pin_segment(dsm_segment *seg);45extern void dsm_unpin_segment(dsm_handle handle);46extern dsm_segment *dsm_find_mapping(dsm_handle handle);47 48/* Informational functions. */49extern void *dsm_segment_address(dsm_segment *seg);50extern Size dsm_segment_map_length(dsm_segment *seg);51extern dsm_handle dsm_segment_handle(dsm_segment *seg);52 53/* Cleanup hooks. */54typedef void (*on_dsm_detach_callback) (dsm_segment *, Datum arg);55extern void on_dsm_detach(dsm_segment *seg,56						  on_dsm_detach_callback function, Datum arg);57extern void cancel_on_dsm_detach(dsm_segment *seg,58								 on_dsm_detach_callback function, Datum arg);59extern void reset_on_dsm_detach(void);60 61#endif							/* DSM_H */62