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-rw-r--r--db2/mutex/mutex.c318
1 files changed, 0 insertions, 318 deletions
diff --git a/db2/mutex/mutex.c b/db2/mutex/mutex.c
deleted file mode 100644
index 2fac14cf3d..0000000000
--- a/db2/mutex/mutex.c
+++ /dev/null
@@ -1,318 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- *	Sleepycat Software.  All rights reserved.
- */
-
-#include "config.h"
-
-#ifndef lint
-static const char sccsid[] = "@(#)mutex.c	10.52 (Sleepycat) 11/8/98";
-#endif /* not lint */
-
-#ifndef NO_SYSTEM_INCLUDES
-#include <sys/types.h>
-
-#include <errno.h>
-#include <fcntl.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#endif
-
-#include "db_int.h"
-
-#ifdef HAVE_SPINLOCKS
-
-#ifdef HAVE_FUNC_AIX
-#define	TSL_INIT(x)
-#define	TSL_SET(x)	(!_check_lock(x, 0, 1))
-#define	TSL_UNSET(x)	_clear_lock(x, 0)
-#endif
-
-#ifdef HAVE_ASSEM_MC68020_GCC
-#include "68020.gcc"
-#endif
-
-#if defined(HAVE_FUNC_MSEM)
-/*
- * !!!
- * Do not remove the MSEM_IF_NOWAIT flag.  The problem is that if a single
- * process makes two msem_lock() calls in a row, the second one returns an
- * error.  We depend on the fact that we can lock against ourselves in the
- * locking subsystem, where we set up a mutex so that we can block ourselves.
- * Tested on OSF1 v4.0.
- */
-#define	TSL_INIT(x)	(msem_init(x, MSEM_UNLOCKED) == NULL)
-#define	TSL_INIT_ERROR	1
-#define	TSL_SET(x)	(!msem_lock(x, MSEM_IF_NOWAIT))
-#define	TSL_UNSET(x)	msem_unlock(x, 0)
-#endif
-
-#ifdef HAVE_FUNC_RELIANT
-#define	TSL_INIT(x)	initspin(x, 1)
-#define	TSL_SET(x)	(cspinlock(x) == 0)
-#define	TSL_UNSET(x)	spinunlock(x)
-#endif
-
-#ifdef HAVE_FUNC_SGI
-#define	TSL_INIT(x)	(init_lock(x) != 0)
-#define	TSL_INIT_ERROR	1
-#define	TSL_SET(x)	(!acquire_lock(x))
-#define	TSL_UNSET(x)	release_lock(x)
-#endif
-
-#ifdef HAVE_FUNC_SOLARIS
-/*
- * Semaphore calls don't work on Solaris 5.5.
- *
- * #define	TSL_INIT(x)	(sema_init(x, 1, USYNC_PROCESS, NULL) != 0)
- * #define	TSL_INIT_ERROR	1
- * #define	TSL_SET(x)	(sema_wait(x) == 0)
- * #define	TSL_UNSET(x)	sema_post(x)
- */
-#define	TSL_INIT(x)
-#define	TSL_SET(x)	(_lock_try(x))
-#define	TSL_UNSET(x)	_lock_clear(x)
-#endif
-
-#ifdef HAVE_FUNC_VMS
-#include <builtins.h>
-#ifdef __ALPHA
-#define	TSL_SET(tsl)	(!__TESTBITSSI(tsl, 0))
-#else /* __VAX */
-#define	TSL_SET(tsl)	(!(int)_BBSSI(0, tsl))
-#endif
-#define	TSL_UNSET(tsl) 	(*(tsl) = 0)
-#define	TSL_INIT(tsl)	TSL_UNSET(tsl)
-#endif
-
-#ifdef HAVE_ASSEM_PARISC_GCC
-#include "parisc.gcc"
-#endif
-
-#ifdef HAVE_ASSEM_SCO_CC
-#include "sco.cc"
-#endif
-
-#ifdef HAVE_ASSEM_SPARC_GCC
-#include "sparc.gcc"
-#endif
-
-#ifdef HAVE_ASSEM_UTS4_CC
-#define TSL_INIT(x)
-#define TSL_SET(x)	(!uts_lock(x, 1))
-#define TSL_UNSET(x)	(*(x) = 0)
-#endif
-
-#ifdef HAVE_ASSEM_X86_GCC
-#include "x86.gcc"
-#endif
-
-#ifdef HAVE_ASSEM_ALPHA
-#include "alpha.h"
-#endif
-
-#ifdef WIN16
-/* Win16 spinlocks are simple because we cannot possibly be preempted. */
-#define	TSL_INIT(tsl)
-#define	TSL_SET(tsl)	(*(tsl) = 1)
-#define	TSL_UNSET(tsl)	(*(tsl) = 0)
-#endif
-
-#if defined(_WIN32)
-/*
- * XXX
- * DBDB this needs to be byte-aligned!!
- */
-#define	TSL_INIT(tsl)
-#define	TSL_SET(tsl)	(!InterlockedExchange((PLONG)tsl, 1))
-#define	TSL_UNSET(tsl)	(*(tsl) = 0)
-#endif
-
-#endif /* HAVE_SPINLOCKS */
-
-/*
- * __db_mutex_init --
- *	Initialize a DB mutex structure.
- *
- * PUBLIC: int __db_mutex_init __P((db_mutex_t *, u_int32_t));
- */
-int
-__db_mutex_init(mp, off)
-	db_mutex_t *mp;
-	u_int32_t off;
-{
-#ifdef DIAGNOSTIC
-	if ((ALIGNTYPE)mp & (MUTEX_ALIGNMENT - 1)) {
-		(void)fprintf(stderr,
-		    "MUTEX ERROR: mutex NOT %d-byte aligned!\n",
-		    MUTEX_ALIGNMENT);
-		abort();
-	}
-#endif
-	memset(mp, 0, sizeof(db_mutex_t));
-
-#ifdef HAVE_SPINLOCKS
-	COMPQUIET(off, 0);
-
-#ifdef TSL_INIT_ERROR
-	if (TSL_INIT(&mp->tsl_resource))
-		return (errno);
-#else
-	TSL_INIT(&mp->tsl_resource);
-#endif
-	mp->spins = __os_spin();
-#else
-	mp->off = off;
-#endif
-	return (0);
-}
-
-#define	MS(n)		((n) * 1000)	/* Milliseconds to micro-seconds. */
-#define	SECOND		(MS(1000))	/* A second's worth of micro-seconds. */
-
-/*
- * __db_mutex_lock
- *	Lock on a mutex, logically blocking if necessary.
- *
- * PUBLIC: int __db_mutex_lock __P((db_mutex_t *, int));
- */
-int
-__db_mutex_lock(mp, fd)
-	db_mutex_t *mp;
-	int fd;
-{
-	u_long usecs;
-#ifdef HAVE_SPINLOCKS
-	int nspins;
-#else
-	struct flock k_lock;
-	pid_t mypid;
-	int locked;
-#endif
-
-	if (!DB_GLOBAL(db_mutexlocks))
-		return (0);
-
-#ifdef HAVE_SPINLOCKS
-	COMPQUIET(fd, 0);
-
-	for (usecs = MS(1);;) {
-		/* Try and acquire the uncontested resource lock for N spins. */
-		for (nspins = mp->spins; nspins > 0; --nspins)
-			if (TSL_SET(&mp->tsl_resource)) {
-#ifdef DIAGNOSTIC
-				if (mp->pid != 0) {
-					(void)fprintf(stderr,
-		    "MUTEX ERROR: __db_mutex_lock: lock currently locked\n");
-					abort();
-				}
-				mp->pid = getpid();
-#endif
-				if (usecs == MS(1))
-					++mp->mutex_set_nowait;
-				else
-					++mp->mutex_set_wait;
-				return (0);
-			}
-
-		/* Yield the processor; wait 1ms initially, up to 1 second. */
-		__os_yield(usecs);
-		if ((usecs <<= 1) > SECOND)
-			usecs = SECOND;
-	}
-	/* NOTREACHED */
-
-#else /* !HAVE_SPINLOCKS */
-
-	/* Initialize the lock. */
-	k_lock.l_whence = SEEK_SET;
-	k_lock.l_start = mp->off;
-	k_lock.l_len = 1;
-
-	for (locked = 0, mypid = getpid();;) {
-		/*
-		 * Wait for the lock to become available; wait 1ms initially,
-		 * up to 1 second.
-		 */
-		for (usecs = MS(1); mp->pid != 0;) {
-			__os_yield(usecs);
-			if ((usecs <<= 1) > SECOND)
-				usecs = SECOND;
-		}
-
-		/* Acquire an exclusive kernel lock. */
-		k_lock.l_type = F_WRLCK;
-		if (fcntl(fd, F_SETLKW, &k_lock))
-			return (errno);
-
-		/* If the resource tsl is still available, it's ours. */
-		if (mp->pid == 0) {
-			locked = 1;
-			mp->pid = mypid;
-		}
-
-		/* Release the kernel lock. */
-		k_lock.l_type = F_UNLCK;
-		if (fcntl(fd, F_SETLK, &k_lock))
-			return (errno);
-
-		/*
-		 * If we got the resource tsl we're done.
-		 *
-		 * !!!
-		 * We can't check to see if the lock is ours, because we may
-		 * be trying to block ourselves in the lock manager, and so
-		 * the holder of the lock that's preventing us from getting
-		 * the lock may be us!  (Seriously.)
-		 */
-		if (locked)
-			break;
-	}
-	return (0);
-#endif /* !HAVE_SPINLOCKS */
-}
-
-/*
- * __db_mutex_unlock --
- *	Release a lock.
- *
- * PUBLIC: int __db_mutex_unlock __P((db_mutex_t *, int));
- */
-int
-__db_mutex_unlock(mp, fd)
-	db_mutex_t *mp;
-	int fd;
-{
-	if (!DB_GLOBAL(db_mutexlocks))
-		return (0);
-
-#ifdef DIAGNOSTIC
-	if (mp->pid == 0) {
-		(void)fprintf(stderr,
-	    "MUTEX ERROR: __db_mutex_unlock: lock already unlocked\n");
-		abort();
-	}
-#endif
-
-#ifdef HAVE_SPINLOCKS
-	COMPQUIET(fd, 0);
-
-#ifdef DIAGNOSTIC
-	mp->pid = 0;
-#endif
-
-	/* Release the resource tsl. */
-	TSL_UNSET(&mp->tsl_resource);
-#else
-	/*
-	 * Release the resource tsl.  We don't have to acquire any locks
-	 * because processes trying to acquire the lock are checking for
-	 * a pid of 0, not a specific value.
-	 */
-	mp->pid = 0;
-#endif
-	return (0);
-}
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