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- /* Copyright (c) 2000, 2014, Oracle and/or its affiliates.
- Copyright (c) 2009, 2014, MariaDB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; version 2 of the License.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */
- /* Defines to make different thread packages compatible */
- #ifndef _my_pthread_h
- #define _my_pthread_h
- #include "my_global.h" /* myf */
- #ifndef ETIME
- #define ETIME ETIMEDOUT /* For FreeBSD */
- #endif
- #ifdef __cplusplus
- #define EXTERNC extern "C"
- extern "C" {
- #else
- #define EXTERNC
- #endif /* __cplusplus */
- #if defined(__WIN__)
- typedef CRITICAL_SECTION pthread_mutex_t;
- typedef DWORD pthread_t;
- typedef struct thread_attr {
- DWORD dwStackSize ;
- DWORD dwCreatingFlag ;
- } pthread_attr_t ;
- typedef struct { int dummy; } pthread_condattr_t;
- /* Implementation of posix conditions */
- typedef struct st_pthread_link {
- DWORD thread_id;
- struct st_pthread_link *next;
- } pthread_link;
- /**
- Implementation of Windows condition variables.
- We use native conditions on Vista and later, and fallback to own
- implementation on earlier OS version.
- */
- typedef union
- {
- /* Native condition (used on Vista and later) */
- CONDITION_VARIABLE native_cond;
- /* Own implementation (used on XP) */
- struct
- {
- uint32 waiting;
- CRITICAL_SECTION lock_waiting;
- enum
- {
- SIGNAL= 0,
- BROADCAST= 1,
- MAX_EVENTS= 2
- } EVENTS;
- HANDLE events[MAX_EVENTS];
- HANDLE broadcast_block_event;
- };
- } pthread_cond_t;
- typedef int pthread_mutexattr_t;
- #define pthread_self() GetCurrentThreadId()
- #define pthread_handler_t EXTERNC void * __cdecl
- typedef void * (__cdecl *pthread_handler)(void *);
- typedef volatile LONG my_pthread_once_t;
- #define MY_PTHREAD_ONCE_INIT 0
- #define MY_PTHREAD_ONCE_INPROGRESS 1
- #define MY_PTHREAD_ONCE_DONE 2
- #if !STRUCT_TIMESPEC_HAS_TV_SEC || !STRUCT_TIMESPEC_HAS_TV_NSEC
- struct timespec {
- time_t tv_sec;
- long tv_nsec;
- };
- #endif
- int win_pthread_mutex_trylock(pthread_mutex_t *mutex);
- int pthread_create(pthread_t *, const pthread_attr_t *, pthread_handler, void *);
- int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr);
- int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);
- int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
- const struct timespec *abstime);
- int pthread_cond_signal(pthread_cond_t *cond);
- int pthread_cond_broadcast(pthread_cond_t *cond);
- int pthread_cond_destroy(pthread_cond_t *cond);
- int pthread_attr_init(pthread_attr_t *connect_att);
- int pthread_attr_setstacksize(pthread_attr_t *connect_att,DWORD stack);
- int pthread_attr_destroy(pthread_attr_t *connect_att);
- int my_pthread_once(my_pthread_once_t *once_control,void (*init_routine)(void));
- static inline struct tm *localtime_r(const time_t *timep, struct tm *tmp)
- {
- localtime_s(tmp, timep);
- return tmp;
- }
- static inline struct tm *gmtime_r(const time_t *clock, struct tm *res)
- {
- gmtime_s(res, clock);
- return res;
- }
- void pthread_exit(void *a);
- int pthread_join(pthread_t thread, void **value_ptr);
- int pthread_cancel(pthread_t thread);
- #ifndef ETIMEDOUT
- #define ETIMEDOUT 145 /* Win32 doesn't have this */
- #endif
- #define getpid() GetCurrentThreadId()
- #define HAVE_LOCALTIME_R 1
- #define _REENTRANT 1
- #define HAVE_PTHREAD_ATTR_SETSTACKSIZE 1
- #undef SAFE_MUTEX /* This will cause conflicts */
- #define pthread_key(T,V) DWORD V
- #define pthread_key_create(A,B) ((*A=TlsAlloc())==0xFFFFFFFF)
- #define pthread_key_delete(A) TlsFree(A)
- #define my_pthread_setspecific_ptr(T,V) (!TlsSetValue((T),(V)))
- #define pthread_setspecific(A,B) (!TlsSetValue((A),(B)))
- #define pthread_getspecific(A) (TlsGetValue(A))
- #define my_pthread_getspecific(T,A) ((T) TlsGetValue(A))
- #define my_pthread_getspecific_ptr(T,V) ((T) TlsGetValue(V))
- #define pthread_equal(A,B) ((A) == (B))
- #define pthread_mutex_init(A,B) (InitializeCriticalSection(A),0)
- #define pthread_mutex_lock(A) (EnterCriticalSection(A),0)
- #define pthread_mutex_trylock(A) win_pthread_mutex_trylock((A))
- #define pthread_mutex_unlock(A) (LeaveCriticalSection(A), 0)
- #define pthread_mutex_destroy(A) (DeleteCriticalSection(A), 0)
- #define pthread_kill(A,B) pthread_dummy((A) ? 0 : ESRCH)
- /* Dummy defines for easier code */
- #define pthread_attr_setdetachstate(A,B) pthread_dummy(0)
- #define pthread_attr_setscope(A,B)
- #define pthread_detach_this_thread()
- #define pthread_condattr_init(A)
- #define pthread_condattr_destroy(A)
- #define pthread_yield() SwitchToThread()
- #define my_sigset(A,B) signal(A,B)
- #else /* Normal threads */
- #ifdef HAVE_rts_threads
- #define sigwait org_sigwait
- #include <signal.h>
- #undef sigwait
- #endif
- #include <pthread.h>
- #ifndef _REENTRANT
- #define _REENTRANT
- #endif
- #ifdef HAVE_THR_SETCONCURRENCY
- #include <thread.h> /* Probably solaris */
- #endif
- #ifdef HAVE_SCHED_H
- #include <sched.h>
- #endif
- #ifdef HAVE_SYNCH_H
- #include <synch.h>
- #endif
- #define pthread_key(T,V) pthread_key_t V
- #define my_pthread_getspecific_ptr(T,V) my_pthread_getspecific(T,(V))
- #define my_pthread_setspecific_ptr(T,V) pthread_setspecific(T,(void*) (V))
- #define pthread_detach_this_thread() { pthread_t tmp=pthread_self() ; pthread_detach(tmp); }
- #define pthread_handler_t EXTERNC void *
- typedef void *(* pthread_handler)(void *);
- #define my_pthread_once_t pthread_once_t
- #if defined(PTHREAD_ONCE_INITIALIZER)
- #define MY_PTHREAD_ONCE_INIT PTHREAD_ONCE_INITIALIZER
- #else
- #define MY_PTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
- #endif
- #define my_pthread_once(C,F) pthread_once(C,F)
- /* Test first for RTS or FSU threads */
- #if defined(PTHREAD_SCOPE_GLOBAL) && !defined(PTHREAD_SCOPE_SYSTEM)
- #define HAVE_rts_threads
- extern int my_pthread_create_detached;
- #define pthread_sigmask(A,B,C) sigprocmask((A),(B),(C))
- #define PTHREAD_CREATE_DETACHED &my_pthread_create_detached
- #define PTHREAD_SCOPE_SYSTEM PTHREAD_SCOPE_GLOBAL
- #define PTHREAD_SCOPE_PROCESS PTHREAD_SCOPE_LOCAL
- #define USE_ALARM_THREAD
- #endif /* defined(PTHREAD_SCOPE_GLOBAL) && !defined(PTHREAD_SCOPE_SYSTEM) */
- #if defined(_BSDI_VERSION) && _BSDI_VERSION < 199910
- int sigwait(sigset_t *set, int *sig);
- #endif
- #define my_sigwait(A,B) sigwait((A),(B))
- #if defined(HAVE_SIGTHREADMASK) && !defined(HAVE_PTHREAD_SIGMASK)
- #define pthread_sigmask(A,B,C) sigthreadmask((A),(B),(C))
- #endif
- #if !defined(HAVE_SIGWAIT) && !defined(HAVE_rts_threads) && !defined(sigwait) && !defined(alpha_linux_port) && !defined(_AIX)
- int sigwait(sigset_t *setp, int *sigp); /* Use our implemention */
- #endif
- /*
- We define my_sigset() and use that instead of the system sigset() so that
- we can favor an implementation based on sigaction(). On some systems, such
- as Mac OS X, sigset() results in flags such as SA_RESTART being set, and
- we want to make sure that no such flags are set.
- */
- #if defined(HAVE_SIGACTION) && !defined(my_sigset)
- #define my_sigset(A,B) do { struct sigaction l_s; sigset_t l_set; \
- DBUG_ASSERT((A) != 0); \
- sigemptyset(&l_set); \
- l_s.sa_handler = (B); \
- l_s.sa_mask = l_set; \
- l_s.sa_flags = 0; \
- sigaction((A), &l_s, NULL); \
- } while (0)
- #elif defined(HAVE_SIGSET) && !defined(my_sigset)
- #define my_sigset(A,B) sigset((A),(B))
- #elif !defined(my_sigset)
- #define my_sigset(A,B) signal((A),(B))
- #endif
- #if !defined(HAVE_PTHREAD_ATTR_SETSCOPE)
- #define pthread_attr_setscope(A,B)
- #undef HAVE_GETHOSTBYADDR_R /* No definition */
- #endif
- #define my_pthread_getspecific(A,B) ((A) pthread_getspecific(B))
- #ifndef HAVE_LOCALTIME_R
- struct tm *localtime_r(const time_t *clock, struct tm *res);
- #endif
- #ifndef HAVE_GMTIME_R
- struct tm *gmtime_r(const time_t *clock, struct tm *res);
- #endif
- #ifdef HAVE_PTHREAD_CONDATTR_CREATE
- /* DCE threads on HPUX 10.20 */
- #define pthread_condattr_init pthread_condattr_create
- #define pthread_condattr_destroy pthread_condattr_delete
- #endif
- /* FSU THREADS */
- #if !defined(HAVE_PTHREAD_KEY_DELETE) && !defined(pthread_key_delete)
- #define pthread_key_delete(A) pthread_dummy(0)
- #endif
- #if defined(HAVE_PTHREAD_ATTR_CREATE) && !defined(HAVE_SIGWAIT)
- /* This is set on AIX_3_2 and Siemens unix (and DEC OSF/1 3.2 too) */
- #define pthread_key_create(A,B) \
- pthread_keycreate(A,(B) ?\
- (pthread_destructor_t) (B) :\
- (pthread_destructor_t) pthread_dummy)
- #define pthread_attr_init(A) pthread_attr_create(A)
- #define pthread_attr_destroy(A) pthread_attr_delete(A)
- #define pthread_attr_setdetachstate(A,B) pthread_dummy(0)
- #define pthread_create(A,B,C,D) pthread_create((A),*(B),(C),(D))
- #ifndef pthread_sigmask
- #define pthread_sigmask(A,B,C) sigprocmask((A),(B),(C))
- #endif
- #define pthread_kill(A,B) pthread_dummy((A) ? 0 : ESRCH)
- #undef pthread_detach_this_thread
- #define pthread_detach_this_thread() { pthread_t tmp=pthread_self() ; pthread_detach(&tmp); }
- #else /* HAVE_PTHREAD_ATTR_CREATE && !HAVE_SIGWAIT */
- #define HAVE_PTHREAD_KILL
- #endif
- #endif /* defined(__WIN__) */
- #if defined(HPUX10) && !defined(DONT_REMAP_PTHREAD_FUNCTIONS)
- #undef pthread_cond_timedwait
- #define pthread_cond_timedwait(a,b,c) my_pthread_cond_timedwait((a),(b),(c))
- int my_pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
- struct timespec *abstime);
- #endif
- #if defined(HPUX10)
- #define pthread_attr_getstacksize(A,B) my_pthread_attr_getstacksize(A,B)
- void my_pthread_attr_getstacksize(pthread_attr_t *attrib, size_t *size);
- #endif
- #if defined(HAVE_POSIX1003_4a_MUTEX) && !defined(DONT_REMAP_PTHREAD_FUNCTIONS)
- #undef pthread_mutex_trylock
- #define pthread_mutex_trylock(a) my_pthread_mutex_trylock((a))
- int my_pthread_mutex_trylock(pthread_mutex_t *mutex);
- #endif
- #if !defined(HAVE_PTHREAD_YIELD_ZERO_ARG)
- /* no pthread_yield() available */
- #ifdef HAVE_SCHED_YIELD
- #define pthread_yield() sched_yield()
- #elif defined(HAVE_PTHREAD_YIELD_NP) /* can be Mac OS X */
- #define pthread_yield() pthread_yield_np()
- #elif defined(HAVE_THR_YIELD)
- #define pthread_yield() thr_yield()
- #endif
- #endif
- /*
- The defines set_timespec and set_timespec_nsec should be used
- for calculating an absolute time at which
- pthread_cond_timedwait should timeout
- */
- #define set_timespec(ABSTIME,SEC) set_timespec_nsec((ABSTIME),(SEC)*1000000000ULL)
- #ifndef set_timespec_nsec
- #define set_timespec_nsec(ABSTIME,NSEC) \
- set_timespec_time_nsec((ABSTIME), my_hrtime().val*1000 + (NSEC))
- #endif /* !set_timespec_nsec */
- /* adapt for two different flavors of struct timespec */
- #ifdef HAVE_TIMESPEC_TS_SEC
- #define MY_tv_sec ts_sec
- #define MY_tv_nsec ts_nsec
- #else
- #define MY_tv_sec tv_sec
- #define MY_tv_nsec tv_nsec
- #endif /* HAVE_TIMESPEC_TS_SEC */
- /**
- Compare two timespec structs.
- @retval 1 If TS1 ends after TS2.
- @retval 0 If TS1 is equal to TS2.
- @retval -1 If TS1 ends before TS2.
- */
- #ifndef cmp_timespec
- #define cmp_timespec(TS1, TS2) \
- ((TS1.MY_tv_sec > TS2.MY_tv_sec || \
- (TS1.MY_tv_sec == TS2.MY_tv_sec && TS1.MY_tv_nsec > TS2.MY_tv_nsec)) ? 1 : \
- ((TS1.MY_tv_sec < TS2.MY_tv_sec || \
- (TS1.MY_tv_sec == TS2.MY_tv_sec && TS1.MY_tv_nsec < TS2.MY_tv_nsec)) ? -1 : 0))
- #endif /* !cmp_timespec */
- #ifndef set_timespec_time_nsec
- #define set_timespec_time_nsec(ABSTIME,NSEC) do { \
- ulonglong _now_= (NSEC); \
- (ABSTIME).MY_tv_sec= (_now_ / 1000000000ULL); \
- (ABSTIME).MY_tv_nsec= (_now_ % 1000000000ULL); \
- } while(0)
- #endif /* !set_timespec_time_nsec */
- /* safe_mutex adds checking to mutex for easier debugging */
- struct st_hash;
- typedef struct st_safe_mutex_t
- {
- pthread_mutex_t global,mutex;
- const char *file, *name;
- uint line,count;
- myf create_flags, active_flags;
- ulong id;
- pthread_t thread;
- struct st_hash *locked_mutex, *used_mutex;
- struct st_safe_mutex_t *prev, *next;
- #ifdef SAFE_MUTEX_DETECT_DESTROY
- struct st_safe_mutex_info_t *info; /* to track destroying of mutexes */
- #endif
- } safe_mutex_t;
- typedef struct st_safe_mutex_deadlock_t
- {
- const char *file, *name;
- safe_mutex_t *mutex;
- uint line;
- ulong count;
- ulong id;
- my_bool warning_only;
- } safe_mutex_deadlock_t;
- #ifdef SAFE_MUTEX_DETECT_DESTROY
- /*
- Used to track the destroying of mutexes. This needs to be a seperate
- structure because the safe_mutex_t structure could be freed before
- the mutexes are destroyed.
- */
- typedef struct st_safe_mutex_info_t
- {
- struct st_safe_mutex_info_t *next;
- struct st_safe_mutex_info_t *prev;
- const char *init_file;
- uint32 init_line;
- } safe_mutex_info_t;
- #endif /* SAFE_MUTEX_DETECT_DESTROY */
- int safe_mutex_init(safe_mutex_t *mp, const pthread_mutexattr_t *attr,
- const char *name, const char *file, uint line);
- int safe_mutex_lock(safe_mutex_t *mp, myf my_flags, const char *file,
- uint line);
- int safe_mutex_unlock(safe_mutex_t *mp,const char *file, uint line);
- int safe_mutex_destroy(safe_mutex_t *mp,const char *file, uint line);
- int safe_cond_wait(pthread_cond_t *cond, safe_mutex_t *mp,const char *file,
- uint line);
- int safe_cond_timedwait(pthread_cond_t *cond, safe_mutex_t *mp,
- const struct timespec *abstime,
- const char *file, uint line);
- void safe_mutex_global_init(void);
- void safe_mutex_end(FILE *file);
- void safe_mutex_free_deadlock_data(safe_mutex_t *mp);
- /* Wrappers if safe mutex is actually used */
- #define MYF_TRY_LOCK 1
- #define MYF_NO_DEADLOCK_DETECTION 2
- #ifdef SAFE_MUTEX
- #define safe_mutex_assert_owner(mp) \
- DBUG_ASSERT((mp)->count > 0 && \
- pthread_equal(pthread_self(), (mp)->thread))
- #define safe_mutex_assert_not_owner(mp) \
- DBUG_ASSERT(! (mp)->count || \
- ! pthread_equal(pthread_self(), (mp)->thread))
- #define safe_mutex_setflags(mp, F) do { (mp)->create_flags|= (F); } while (0)
- #define my_cond_timedwait(A,B,C) safe_cond_timedwait((A),(B),(C),__FILE__,__LINE__)
- #define my_cond_wait(A,B) safe_cond_wait((A), (B), __FILE__, __LINE__)
- #else
- #define safe_mutex_assert_owner(mp) do {} while (0)
- #define safe_mutex_assert_not_owner(mp) do {} while (0)
- #define safe_mutex_setflags(mp, F) do {} while (0)
- #if defined(MY_PTHREAD_FASTMUTEX)
- #define my_cond_timedwait(A,B,C) pthread_cond_timedwait((A), &(B)->mutex, (C))
- #define my_cond_wait(A,B) pthread_cond_wait((A), &(B)->mutex)
- #else
- #define my_cond_timedwait(A,B,C) pthread_cond_timedwait((A),(B),(C))
- #define my_cond_wait(A,B) pthread_cond_wait((A), (B))
- #endif /* MY_PTHREAD_FASTMUTEX */
- #endif /* !SAFE_MUTEX */
- #if defined(MY_PTHREAD_FASTMUTEX) && !defined(SAFE_MUTEX)
- typedef struct st_my_pthread_fastmutex_t
- {
- pthread_mutex_t mutex;
- uint spins;
- uint rng_state;
- } my_pthread_fastmutex_t;
- void fastmutex_global_init(void);
- int my_pthread_fastmutex_init(my_pthread_fastmutex_t *mp,
- const pthread_mutexattr_t *attr);
- int my_pthread_fastmutex_lock(my_pthread_fastmutex_t *mp);
- #endif /* defined(MY_PTHREAD_FASTMUTEX) && !defined(SAFE_MUTEX) */
- /* READ-WRITE thread locking */
- #if defined(USE_MUTEX_INSTEAD_OF_RW_LOCKS)
- /* use these defs for simple mutex locking */
- #define rw_lock_t pthread_mutex_t
- #define my_rwlock_init(A,B) pthread_mutex_init((A),(B))
- #define rw_rdlock(A) pthread_mutex_lock((A))
- #define rw_wrlock(A) pthread_mutex_lock((A))
- #define rw_tryrdlock(A) pthread_mutex_trylock((A))
- #define rw_trywrlock(A) pthread_mutex_trylock((A))
- #define rw_unlock(A) pthread_mutex_unlock((A))
- #define rwlock_destroy(A) pthread_mutex_destroy((A))
- #elif defined(HAVE_PTHREAD_RWLOCK_RDLOCK)
- #define rw_lock_t pthread_rwlock_t
- #define my_rwlock_init(A,B) pthread_rwlock_init((A),(B))
- #define rw_rdlock(A) pthread_rwlock_rdlock(A)
- #define rw_wrlock(A) pthread_rwlock_wrlock(A)
- #define rw_tryrdlock(A) pthread_rwlock_tryrdlock((A))
- #define rw_trywrlock(A) pthread_rwlock_trywrlock((A))
- #define rw_unlock(A) pthread_rwlock_unlock(A)
- #define rwlock_destroy(A) pthread_rwlock_destroy(A)
- #elif defined(HAVE_RWLOCK_INIT)
- #ifdef HAVE_RWLOCK_T /* For example Solaris 2.6-> */
- #define rw_lock_t rwlock_t
- #endif
- #define my_rwlock_init(A,B) rwlock_init((A),USYNC_THREAD,0)
- #else
- /* Use our own version of read/write locks */
- #define NEED_MY_RW_LOCK 1
- #define rw_lock_t my_rw_lock_t
- #define my_rwlock_init(A,B) my_rw_init((A))
- #define rw_rdlock(A) my_rw_rdlock((A))
- #define rw_wrlock(A) my_rw_wrlock((A))
- #define rw_tryrdlock(A) my_rw_tryrdlock((A))
- #define rw_trywrlock(A) my_rw_trywrlock((A))
- #define rw_unlock(A) my_rw_unlock((A))
- #define rwlock_destroy(A) my_rw_destroy((A))
- #define rw_lock_assert_write_owner(A) my_rw_lock_assert_write_owner((A))
- #define rw_lock_assert_not_write_owner(A) my_rw_lock_assert_not_write_owner((A))
- #endif /* USE_MUTEX_INSTEAD_OF_RW_LOCKS */
- /**
- Portable implementation of special type of read-write locks.
- These locks have two properties which are unusual for rwlocks:
- 1) They "prefer readers" in the sense that they do not allow
- situations in which rwlock is rd-locked and there is a
- pending rd-lock which is blocked (e.g. due to pending
- request for wr-lock).
- This is a stronger guarantee than one which is provided for
- PTHREAD_RWLOCK_PREFER_READER_NP rwlocks in Linux.
- MDL subsystem deadlock detector relies on this property for
- its correctness.
- 2) They are optimized for uncontended wr-lock/unlock case.
- This is scenario in which they are most oftenly used
- within MDL subsystem. Optimizing for it gives significant
- performance improvements in some of tests involving many
- connections.
- Another important requirement imposed on this type of rwlock
- by the MDL subsystem is that it should be OK to destroy rwlock
- object which is in unlocked state even though some threads might
- have not yet fully left unlock operation for it (of course there
- is an external guarantee that no thread will try to lock rwlock
- which is destroyed).
- Putting it another way the unlock operation should not access
- rwlock data after changing its state to unlocked.
- TODO/FIXME: We should consider alleviating this requirement as
- it blocks us from doing certain performance optimizations.
- */
- typedef struct st_rw_pr_lock_t {
- /**
- Lock which protects the structure.
- Also held for the duration of wr-lock.
- */
- pthread_mutex_t lock;
- /**
- Condition variable which is used to wake-up
- writers waiting for readers to go away.
- */
- pthread_cond_t no_active_readers;
- /** Number of active readers. */
- uint active_readers;
- /** Number of writers waiting for readers to go away. */
- uint writers_waiting_readers;
- /** Indicates whether there is an active writer. */
- my_bool active_writer;
- #ifdef SAFE_MUTEX
- /** Thread holding wr-lock (for debug purposes only). */
- pthread_t writer_thread;
- #endif
- } rw_pr_lock_t;
- extern int rw_pr_init(rw_pr_lock_t *);
- extern int rw_pr_rdlock(rw_pr_lock_t *);
- extern int rw_pr_wrlock(rw_pr_lock_t *);
- extern int rw_pr_unlock(rw_pr_lock_t *);
- extern int rw_pr_destroy(rw_pr_lock_t *);
- #ifdef SAFE_MUTEX
- #define rw_pr_lock_assert_write_owner(A) \
- DBUG_ASSERT((A)->active_writer && pthread_equal(pthread_self(), \
- (A)->writer_thread))
- #define rw_pr_lock_assert_not_write_owner(A) \
- DBUG_ASSERT(! (A)->active_writer || ! pthread_equal(pthread_self(), \
- (A)->writer_thread))
- #else
- #define rw_pr_lock_assert_write_owner(A)
- #define rw_pr_lock_assert_not_write_owner(A)
- #endif /* SAFE_MUTEX */
- #ifdef NEED_MY_RW_LOCK
- #ifdef _WIN32
- /**
- Implementation of Windows rwlock.
- We use native (slim) rwlocks on Win7 and later, and fallback to portable
- implementation on earlier Windows.
- slim rwlock are also available on Vista/WS2008, but we do not use it
- ("trylock" APIs are missing on Vista)
- */
- typedef union
- {
- /* Native rwlock (is_srwlock == TRUE) */
- struct
- {
- SRWLOCK srwlock; /* native reader writer lock */
- BOOL have_exclusive_srwlock; /* used for unlock */
- };
- /*
- Portable implementation (is_srwlock == FALSE)
- Fields are identical with Unix my_rw_lock_t fields.
- */
- struct
- {
- pthread_mutex_t lock; /* lock for structure */
- pthread_cond_t readers; /* waiting readers */
- pthread_cond_t writers; /* waiting writers */
- int state; /* -1:writer,0:free,>0:readers */
- int waiters; /* number of waiting writers */
- #ifdef SAFE_MUTEX
- pthread_t write_thread;
- #endif
- };
- } my_rw_lock_t;
- #else /* _WIN32 */
- /*
- On systems which don't support native read/write locks we have
- to use own implementation.
- */
- typedef struct st_my_rw_lock_t {
- pthread_mutex_t lock; /* lock for structure */
- pthread_cond_t readers; /* waiting readers */
- pthread_cond_t writers; /* waiting writers */
- int state; /* -1:writer,0:free,>0:readers */
- int waiters; /* number of waiting writers */
- #ifdef SAFE_MUTEX
- pthread_t write_thread;
- #endif
- } my_rw_lock_t;
- #endif /*! _WIN32 */
- extern int my_rw_init(my_rw_lock_t *);
- extern int my_rw_destroy(my_rw_lock_t *);
- extern int my_rw_rdlock(my_rw_lock_t *);
- extern int my_rw_wrlock(my_rw_lock_t *);
- extern int my_rw_unlock(my_rw_lock_t *);
- extern int my_rw_tryrdlock(my_rw_lock_t *);
- extern int my_rw_trywrlock(my_rw_lock_t *);
- #ifdef SAFE_MUTEX
- #define my_rw_lock_assert_write_owner(A) \
- DBUG_ASSERT((A)->state == -1 && pthread_equal(pthread_self(), \
- (A)->write_thread))
- #define my_rw_lock_assert_not_write_owner(A) \
- DBUG_ASSERT((A)->state >= 0 || ! pthread_equal(pthread_self(), \
- (A)->write_thread))
- #else
- #define my_rw_lock_assert_write_owner(A)
- #define my_rw_lock_assert_not_write_owner(A)
- #endif
- #endif /* NEED_MY_RW_LOCK */
- #define GETHOSTBYADDR_BUFF_SIZE 2048
- #ifndef HAVE_THR_SETCONCURRENCY
- #define thr_setconcurrency(A) pthread_dummy(0)
- #endif
- #if !defined(HAVE_PTHREAD_ATTR_SETSTACKSIZE) && ! defined(pthread_attr_setstacksize)
- #define pthread_attr_setstacksize(A,B) pthread_dummy(0)
- #endif
- /* Define mutex types, see my_thr_init.c */
- #define MY_MUTEX_INIT_SLOW NULL
- #ifdef PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
- extern pthread_mutexattr_t my_fast_mutexattr;
- #define MY_MUTEX_INIT_FAST &my_fast_mutexattr
- #else
- #define MY_MUTEX_INIT_FAST NULL
- #endif
- #ifdef PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP
- extern pthread_mutexattr_t my_errorcheck_mutexattr;
- #define MY_MUTEX_INIT_ERRCHK &my_errorcheck_mutexattr
- #else
- #define MY_MUTEX_INIT_ERRCHK NULL
- #endif
- #ifndef ESRCH
- /* Define it to something */
- #define ESRCH 1
- #endif
- typedef ulong my_thread_id;
- extern void my_threadattr_global_init(void);
- extern my_bool my_thread_global_init(void);
- extern void my_thread_global_reinit(void);
- extern void my_thread_global_end(void);
- extern my_bool my_thread_init(void);
- extern void my_thread_end(void);
- extern const char *my_thread_name(void);
- extern my_thread_id my_thread_dbug_id(void);
- extern int pthread_dummy(int);
- extern void my_mutex_init(void);
- extern void my_mutex_end(void);
- /* All thread specific variables are in the following struct */
- #define THREAD_NAME_SIZE 10
- #ifndef DEFAULT_THREAD_STACK
- /*
- We need to have at least 256K stack to handle calls to myisamchk_init()
- with the current number of keys and key parts.
- */
- #define DEFAULT_THREAD_STACK (289*1024L)
- #endif
- #define MY_PTHREAD_LOCK_READ 0
- #define MY_PTHREAD_LOCK_WRITE 1
- #include <mysql/psi/mysql_thread.h>
- #define INSTRUMENT_ME 0
- struct st_my_thread_var
- {
- int thr_errno;
- mysql_cond_t suspend;
- mysql_mutex_t mutex;
- mysql_mutex_t * volatile current_mutex;
- mysql_cond_t * volatile current_cond;
- pthread_t pthread_self;
- my_thread_id id;
- int volatile abort;
- my_bool init;
- struct st_my_thread_var *next,**prev;
- void *keycache_link;
- uint lock_type; /* used by conditional release the queue */
- void *stack_ends_here;
- safe_mutex_t *mutex_in_use;
- #ifndef DBUG_OFF
- void *dbug;
- char name[THREAD_NAME_SIZE+1];
- #endif
- };
- extern struct st_my_thread_var *_my_thread_var(void) __attribute__ ((const));
- extern void **my_thread_var_dbug(void);
- extern safe_mutex_t **my_thread_var_mutex_in_use(void);
- extern uint my_thread_end_wait_time;
- extern my_bool safe_mutex_deadlock_detector;
- #define my_thread_var (_my_thread_var())
- #define my_errno my_thread_var->thr_errno
- /*
- Keep track of shutdown,signal, and main threads so that my_end() will not
- report errors with them
- */
- /* Which kind of thread library is in use */
- #define THD_LIB_OTHER 1
- #define THD_LIB_NPTL 2
- #define THD_LIB_LT 4
- extern uint thd_lib_detected;
- /*
- thread_safe_xxx functions are for critical statistic or counters.
- The implementation is guaranteed to be thread safe, on all platforms.
- Note that the calling code should *not* assume the counter is protected
- by the mutex given, as the implementation of these helpers may change
- to use my_atomic operations instead.
- */
- #ifndef thread_safe_increment
- #ifdef _WIN32
- #define thread_safe_increment(V,L) InterlockedIncrement((long*) &(V))
- #define thread_safe_decrement(V,L) InterlockedDecrement((long*) &(V))
- #else
- #define thread_safe_increment(V,L) \
- (mysql_mutex_lock((L)), (V)++, mysql_mutex_unlock((L)))
- #define thread_safe_decrement(V,L) \
- (mysql_mutex_lock((L)), (V)--, mysql_mutex_unlock((L)))
- #endif
- #endif
- #ifndef thread_safe_add
- #ifdef _WIN32
- #define thread_safe_add(V,C,L) InterlockedExchangeAdd((long*) &(V),(C))
- #define thread_safe_sub(V,C,L) InterlockedExchangeAdd((long*) &(V),-(long) (C))
- #else
- #define thread_safe_add(V,C,L) \
- (mysql_mutex_lock((L)), (V)+=(C), mysql_mutex_unlock((L)))
- #define thread_safe_sub(V,C,L) \
- (mysql_mutex_lock((L)), (V)-=(C), mysql_mutex_unlock((L)))
- #endif
- #endif
- /*
- statistics_xxx functions are for non critical statistic,
- maintained in global variables.
- When compiling with SAFE_STATISTICS:
- - race conditions can not occur.
- - some locking occurs, which may cause performance degradation.
- When compiling without SAFE_STATISTICS:
- - race conditions can occur, making the result slightly inaccurate.
- - the lock given is not honored.
- */
- #ifdef SAFE_STATISTICS
- #define statistic_increment(V,L) thread_safe_increment((V),(L))
- #define statistic_decrement(V,L) thread_safe_decrement((V),(L))
- #define statistic_add(V,C,L) thread_safe_add((V),(C),(L))
- #define statistic_sub(V,C,L) thread_safe_sub((V),(C),(L))
- #else
- #define statistic_decrement(V,L) (V)--
- #define statistic_increment(V,L) (V)++
- #define statistic_add(V,C,L) (V)+=(C)
- #define statistic_sub(V,C,L) (V)-=(C)
- #endif /* SAFE_STATISTICS */
- /*
- No locking needed, the counter is owned by the thread
- */
- #define status_var_increment(V) (V)++
- #define status_var_decrement(V) (V)--
- #define status_var_add(V,C) (V)+=(C)
- #define status_var_sub(V,C) (V)-=(C)
- #ifdef SAFE_MUTEX
- #define mysql_mutex_record_order(A,B) \
- do { \
- mysql_mutex_lock(A); mysql_mutex_lock(B); \
- mysql_mutex_unlock(B); mysql_mutex_unlock(A); \
- } while(0)
- #else
- #define mysql_mutex_record_order(A,B) do { } while(0)
- #endif
- /* At least Windows and NetBSD do not have this definition */
- #ifndef PTHREAD_STACK_MIN
- #define PTHREAD_STACK_MIN 65536
- #endif
- #ifdef __cplusplus
- }
- #endif
- #endif /* _my_ptread_h */
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