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authorUlrich Drepper <drepper@redhat.com>2000-01-02 06:01:06 +0000
committerUlrich Drepper <drepper@redhat.com>2000-01-02 06:01:06 +0000
commit8d6f1731fcd082e4f744ba9cb4bde4be7c08f1b3 (patch)
tree099a250d7366aef2ab028fdb24f0d692cd784b4a /db2/mutex/mutex.c
parent9a6450d578556c11e7c173d2f28362345b8f1258 (diff)
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Update.
* Makeconfig (all-subdirs): Remove db and db2. * db/*: Removed. * db2/*: Removed.
Diffstat (limited to 'db2/mutex/mutex.c')
-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);
-}