1N/A/*
1N/A * Copyright (c) 2000-2001, 2003, 2005 Sendmail, Inc. and its suppliers.
1N/A * All rights reserved.
1N/A *
1N/A * By using this file, you agree to the terms and conditions set
1N/A * forth in the LICENSE file which can be found at the top level of
1N/A * the sendmail distribution.
1N/A */
1N/A
1N/A#pragma ident "%Z%%M% %I% %E% SMI"
1N/A
1N/A#include <sm/gen.h>
1N/ASM_RCSID("@(#)$Id: shm.c,v 1.19 2005/07/14 22:34:28 ca Exp $")
1N/A
1N/A#if SM_CONF_SHM
1N/A# include <stdlib.h>
1N/A# include <unistd.h>
1N/A# include <errno.h>
1N/A# include <sm/string.h>
1N/A# include <sm/shm.h>
1N/A
1N/A
1N/A/*
1N/A** SM_SHMSTART -- initialize shared memory segment.
1N/A**
1N/A** Parameters:
1N/A** key -- key for shared memory.
1N/A** size -- size of segment.
1N/A** shmflag -- initial flags.
1N/A** shmid -- pointer to return id.
1N/A** owner -- create segment.
1N/A**
1N/A** Returns:
1N/A** pointer to shared memory segment,
1N/A** NULL on failure.
1N/A**
1N/A** Side Effects:
1N/A** attaches shared memory segment.
1N/A*/
1N/A
1N/Avoid *
1N/Asm_shmstart(key, size, shmflg, shmid, owner)
1N/A key_t key;
1N/A int size;
1N/A int shmflg;
1N/A int *shmid;
1N/A bool owner;
1N/A{
1N/A int save_errno;
1N/A void *shm = SM_SHM_NULL;
1N/A
1N/A /* default: user/group accessible */
1N/A if (shmflg == 0)
1N/A shmflg = SHM_R|SHM_W|(SHM_R>>3)|(SHM_W>>3);
1N/A if (owner)
1N/A shmflg |= IPC_CREAT|IPC_EXCL;
1N/A *shmid = shmget(key, size, shmflg);
1N/A if (*shmid < 0)
1N/A goto error;
1N/A
1N/A shm = shmat(*shmid, (void *) 0, 0);
1N/A if (shm == SM_SHM_NULL)
1N/A goto error;
1N/A
1N/A return shm;
1N/A
1N/A error:
1N/A save_errno = errno;
1N/A if (shm != SM_SHM_NULL || *shmid >= 0)
1N/A sm_shmstop(shm, *shmid, owner);
1N/A *shmid = SM_SHM_NO_ID;
1N/A errno = save_errno;
1N/A return (void *) 0;
1N/A}
1N/A
1N/A
1N/A/*
1N/A** SM_SHMSTOP -- stop using shared memory segment.
1N/A**
1N/A** Parameters:
1N/A** shm -- pointer to shared memory.
1N/A** shmid -- id.
1N/A** owner -- delete segment.
1N/A**
1N/A** Returns:
1N/A** 0 on success.
1N/A** < 0 on failure.
1N/A**
1N/A** Side Effects:
1N/A** detaches (and maybe removes) shared memory segment.
1N/A*/
1N/A
1N/A
1N/Aint
1N/Asm_shmstop(shm, shmid, owner)
1N/A void *shm;
1N/A int shmid;
1N/A bool owner;
1N/A{
1N/A int r;
1N/A
1N/A if (shm != SM_SHM_NULL && (r = shmdt(shm)) < 0)
1N/A return r;
1N/A if (owner && shmid >= 0 && (r = shmctl(shmid, IPC_RMID, NULL)) < 0)
1N/A return r;
1N/A return 0;
1N/A}
1N/A
1N/A
1N/A/*
1N/A** SM_SHMSETOWNER -- set owner/group/mode of shared memory segment.
1N/A**
1N/A** Parameters:
1N/A** shmid -- id.
1N/A** uid -- uid to use
1N/A** gid -- gid to use
1N/A** mode -- mode to use
1N/A**
1N/A** Returns:
1N/A** 0 on success.
1N/A** < 0 on failure.
1N/A*/
1N/A
1N/Aint
1N/Asm_shmsetowner(shmid, uid, gid, mode)
1N/A int shmid;
1N/A uid_t uid;
1N/A gid_t gid;
1N/A mode_t mode;
1N/A{
1N/A int r;
1N/A struct shmid_ds shmid_ds;
1N/A
1N/A memset(&shmid_ds, 0, sizeof(shmid_ds));
1N/A if ((r = shmctl(shmid, IPC_STAT, &shmid_ds)) < 0)
1N/A return r;
1N/A shmid_ds.shm_perm.uid = uid;
1N/A shmid_ds.shm_perm.gid = gid;
1N/A shmid_ds.shm_perm.mode = mode;
1N/A if ((r = shmctl(shmid, IPC_SET, &shmid_ds)) < 0)
1N/A return r;
1N/A return 0;
1N/A}
1N/A#endif /* SM_CONF_SHM */