codekingpro/portable-devtools

1/*-------------------------------------------------------------------------2 *3 * mem.h4 *	  portability definitions for various memory operations5 *6 * Copyright (c) 2001-2023, PostgreSQL Global Development Group7 *8 * src/include/portability/mem.h9 *10 *-------------------------------------------------------------------------11 */12#ifndef MEM_H13#define MEM_H14 15#define IPCProtection	(0600)	/* access/modify by user only */16 17#ifdef SHM_SHARE_MMU			/* use intimate shared memory on Solaris */18#define PG_SHMAT_FLAGS			SHM_SHARE_MMU19#else20#define PG_SHMAT_FLAGS			021#endif22 23/* Linux prefers MAP_ANONYMOUS, but the flag is called MAP_ANON on other systems. */24#ifndef MAP_ANONYMOUS25#define MAP_ANONYMOUS			MAP_ANON26#endif27 28/* BSD-derived systems have MAP_HASSEMAPHORE, but it's not present (or needed) on Linux. */29#ifndef MAP_HASSEMAPHORE30#define MAP_HASSEMAPHORE		031#endif32 33/*34 * BSD-derived systems use the MAP_NOSYNC flag to prevent dirty mmap(2)35 * pages from being gratuitously flushed to disk.36 */37#ifndef MAP_NOSYNC38#define MAP_NOSYNC			039#endif40 41#define PG_MMAP_FLAGS			(MAP_SHARED|MAP_ANONYMOUS|MAP_HASSEMAPHORE)42 43/* Some really old systems don't define MAP_FAILED. */44#ifndef MAP_FAILED45#define MAP_FAILED ((void *) -1)46#endif47 48#endif							/* MEM_H */49