/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996-2002 * Sleepycat Software. All rights reserved. */ #include "db_config.h" #ifndef lint static const char revid[] = "$Id: os_region.c,v 11.15 2002/07/12 18:56:51 bostic Exp $"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES #include <sys/types.h> #endif #include "db_int.h" /* * __os_r_attach -- * Attach to a shared memory region. * * PUBLIC: int __os_r_attach __P((DB_ENV *, REGINFO *, REGION *)); */ int __os_r_attach(dbenv, infop, rp) DB_ENV *dbenv; REGINFO *infop; REGION *rp; { int ret; /* Round off the requested size for the underlying VM. */ OS_VMROUNDOFF(rp->size); #ifdef DB_REGIONSIZE_MAX /* Some architectures have hard limits on the maximum region size. */ if (rp->size > DB_REGIONSIZE_MAX) { __db_err(dbenv, "region size %lu is too large; maximum is %lu", (u_long)rp->size, (u_long)DB_REGIONSIZE_MAX); return (EINVAL); } #endif /* * If a region is private, malloc the memory. * * !!! * If this fails because the region is too large to malloc, mmap(2) * using the MAP_ANON or MAP_ANONYMOUS flags would be an alternative. * I don't know of any architectures (yet!) where malloc is a problem. */ if (F_ISSET(dbenv, DB_ENV_PRIVATE)) { #if defined(MUTEX_NO_MALLOC_LOCKS) /* * !!! * There exist spinlocks that don't work in malloc memory, e.g., * the HP/UX msemaphore interface. If we don't have locks that * will work in malloc memory, we better not be private or not * be threaded. */ if (F_ISSET(dbenv, DB_ENV_THREAD)) { __db_err(dbenv, "%s", "architecture does not support locks inside process-local (malloc) memory"); __db_err(dbenv, "%s", "application may not specify both DB_PRIVATE and DB_THREAD"); return (EINVAL); } #endif if ((ret = __os_malloc(dbenv, rp->size, &infop->addr)) != 0) return (ret); #if defined(UMRW) && !defined(DIAGNOSTIC) memset(infop->addr, CLEAR_BYTE, rp->size); #endif return (0); } /* If the user replaced the map call, call through their interface. */ if (DB_GLOBAL(j_map) != NULL) return (DB_GLOBAL(j_map)(infop->name, rp->size, 1, 0, &infop->addr)); return (__os_r_sysattach(dbenv, infop, rp)); } /* * __os_r_detach -- * Detach from a shared memory region. * * PUBLIC: int __os_r_detach __P((DB_ENV *, REGINFO *, int)); */ int __os_r_detach(dbenv, infop, destroy) DB_ENV *dbenv; REGINFO *infop; int destroy; { REGION *rp; rp = infop->rp; /* If a region is private, free the memory. */ if (F_ISSET(dbenv, DB_ENV_PRIVATE)) { __os_free(dbenv, infop->addr); return (0); } /* If the user replaced the map call, call through their interface. */ if (DB_GLOBAL(j_unmap) != NULL) return (DB_GLOBAL(j_unmap)(infop->addr, rp->size)); return (__os_r_sysdetach(dbenv, infop, destroy)); }