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+/* Private libc-internal interface for mutex locks. NPTL version.
+ Copyright (C) 1996-2015 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _LIBC_LOCKP_H
+#define _LIBC_LOCKP_H 1
+
+#include <pthread.h>
+#define __need_NULL
+#include <stddef.h>
+
+
+/* Fortunately Linux now has a mean to do locking which is realtime
+ safe without the aid of the thread library. We also need no fancy
+ options like error checking mutexes etc. We only need simple
+ locks, maybe recursive. This can be easily and cheaply implemented
+ using futexes. We will use them everywhere except in ld.so since
+ ld.so might be used on old kernels with a different libc.so. */
+#include <lowlevellock.h>
+#include <tls.h>
+#include <pthread-functions.h>
+
+#if IS_IN (libpthread)
+/* This gets us the declarations of the __pthread_* internal names,
+ and hidden_proto for them. */
+# include <nptl/pthreadP.h>
+#endif
+
+/* Mutex type. */
+#if !IS_IN (libc) && !IS_IN (libpthread)
+typedef pthread_mutex_t __libc_lock_t;
+#else
+typedef int __libc_lock_t;
+#endif
+typedef struct { pthread_mutex_t mutex; } __rtld_lock_recursive_t;
+typedef pthread_rwlock_t __libc_rwlock_t;
+
+/* Type for key to thread-specific data. */
+typedef pthread_key_t __libc_key_t;
+
+/* Define a lock variable NAME with storage class CLASS. The lock must be
+ initialized with __libc_lock_init before it can be used (or define it
+ with __libc_lock_define_initialized, below). Use `extern' for CLASS to
+ declare a lock defined in another module. In public structure
+ definitions you must use a pointer to the lock structure (i.e., NAME
+ begins with a `*'), because its storage size will not be known outside
+ of libc. */
+#define __libc_lock_define(CLASS,NAME) \
+ CLASS __libc_lock_t NAME;
+#define __libc_rwlock_define(CLASS,NAME) \
+ CLASS __libc_rwlock_t NAME;
+#define __rtld_lock_define_recursive(CLASS,NAME) \
+ CLASS __rtld_lock_recursive_t NAME;
+
+/* Define an initialized lock variable NAME with storage class CLASS.
+
+ For the C library we take a deeper look at the initializer. For
+ this implementation all fields are initialized to zero. Therefore
+ we don't initialize the variable which allows putting it into the
+ BSS section. (Except on PA-RISC and other odd architectures, where
+ initialized locks must be set to one due to the lack of normal
+ atomic operations.) */
+
+#if IS_IN (libc) || IS_IN (libpthread)
+# if LLL_LOCK_INITIALIZER == 0
+# define __libc_lock_define_initialized(CLASS,NAME) \
+ CLASS __libc_lock_t NAME;
+# else
+# define __libc_lock_define_initialized(CLASS,NAME) \
+ CLASS __libc_lock_t NAME = LLL_LOCK_INITIALIZER;
+# endif
+#else
+# define __libc_lock_define_initialized(CLASS,NAME) \
+ CLASS __libc_lock_t NAME;
+#endif
+
+#define __libc_rwlock_define_initialized(CLASS,NAME) \
+ CLASS __libc_rwlock_t NAME = PTHREAD_RWLOCK_INITIALIZER;
+
+#define __rtld_lock_define_initialized_recursive(CLASS,NAME) \
+ CLASS __rtld_lock_recursive_t NAME = _RTLD_LOCK_RECURSIVE_INITIALIZER;
+#define _RTLD_LOCK_RECURSIVE_INITIALIZER \
+ {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}
+
+#define __rtld_lock_initialize(NAME) \
+ (void) ((NAME) = (__rtld_lock_recursive_t) _RTLD_LOCK_RECURSIVE_INITIALIZER)
+
+/* If we check for a weakly referenced symbol and then perform a
+ normal jump to it te code generated for some platforms in case of
+ PIC is unnecessarily slow. What would happen is that the function
+ is first referenced as data and then it is called indirectly
+ through the PLT. We can make this a direct jump. */
+#ifdef __PIC__
+# define __libc_maybe_call(FUNC, ARGS, ELSE) \
+ (__extension__ ({ __typeof (FUNC) *_fn = (FUNC); \
+ _fn != NULL ? (*_fn) ARGS : ELSE; }))
+#else
+# define __libc_maybe_call(FUNC, ARGS, ELSE) \
+ (FUNC != NULL ? FUNC ARGS : ELSE)
+#endif
+
+/* Call thread functions through the function pointer table. */
+#if defined SHARED && IS_IN (libc)
+# define PTFAVAIL(NAME) __libc_pthread_functions_init
+# define __libc_ptf_call(FUNC, ARGS, ELSE) \
+ (__libc_pthread_functions_init ? PTHFCT_CALL (ptr_##FUNC, ARGS) : ELSE)
+# define __libc_ptf_call_always(FUNC, ARGS) \
+ PTHFCT_CALL (ptr_##FUNC, ARGS)
+#elif IS_IN (libpthread)
+# define PTFAVAIL(NAME) 1
+# define __libc_ptf_call(FUNC, ARGS, ELSE) \
+ FUNC ARGS
+# define __libc_ptf_call_always(FUNC, ARGS) \
+ FUNC ARGS
+#else
+# define PTFAVAIL(NAME) (NAME != NULL)
+# define __libc_ptf_call(FUNC, ARGS, ELSE) \
+ __libc_maybe_call (FUNC, ARGS, ELSE)
+# define __libc_ptf_call_always(FUNC, ARGS) \
+ FUNC ARGS
+#endif
+
+
+/* Initialize the named lock variable, leaving it in a consistent, unlocked
+ state. */
+#if IS_IN (libc) || IS_IN (libpthread)
+# define __libc_lock_init(NAME) \
+ ((void) ((NAME) = LLL_LOCK_INITIALIZER))
+#else
+# define __libc_lock_init(NAME) \
+ __libc_maybe_call (__pthread_mutex_init, (&(NAME), NULL), 0)
+#endif
+#if defined SHARED && IS_IN (libc)
+/* ((NAME) = (__libc_rwlock_t) PTHREAD_RWLOCK_INITIALIZER) is inefficient. */
+# define __libc_rwlock_init(NAME) \
+ ((void) __builtin_memset (&(NAME), '\0', sizeof (NAME)))
+#else
+# define __libc_rwlock_init(NAME) \
+ __libc_maybe_call (__pthread_rwlock_init, (&(NAME), NULL), 0)
+#endif
+
+/* Finalize the named lock variable, which must be locked. It cannot be
+ used again until __libc_lock_init is called again on it. This must be
+ called on a lock variable before the containing storage is reused. */
+#if IS_IN (libc) || IS_IN (libpthread)
+# define __libc_lock_fini(NAME) ((void) 0)
+#else
+# define __libc_lock_fini(NAME) \
+ __libc_maybe_call (__pthread_mutex_destroy, (&(NAME)), 0)
+#endif
+#if defined SHARED && IS_IN (libc)
+# define __libc_rwlock_fini(NAME) ((void) 0)
+#else
+# define __libc_rwlock_fini(NAME) \
+ __libc_maybe_call (__pthread_rwlock_destroy, (&(NAME)), 0)
+#endif
+
+/* Lock the named lock variable. */
+#if IS_IN (libc) || IS_IN (libpthread)
+# ifndef __libc_lock_lock
+# define __libc_lock_lock(NAME) \
+ ({ lll_lock (NAME, LLL_PRIVATE); 0; })
+# endif
+#else
+# undef __libc_lock_lock
+# define __libc_lock_lock(NAME) \
+ __libc_maybe_call (__pthread_mutex_lock, (&(NAME)), 0)
+#endif
+#define __libc_rwlock_rdlock(NAME) \
+ __libc_ptf_call (__pthread_rwlock_rdlock, (&(NAME)), 0)
+#define __libc_rwlock_wrlock(NAME) \
+ __libc_ptf_call (__pthread_rwlock_wrlock, (&(NAME)), 0)
+
+/* Try to lock the named lock variable. */
+#if IS_IN (libc) || IS_IN (libpthread)
+# ifndef __libc_lock_trylock
+# define __libc_lock_trylock(NAME) \
+ lll_trylock (NAME)
+# endif
+#else
+# undef __libc_lock_trylock
+# define __libc_lock_trylock(NAME) \
+ __libc_maybe_call (__pthread_mutex_trylock, (&(NAME)), 0)
+#endif
+#define __libc_rwlock_tryrdlock(NAME) \
+ __libc_maybe_call (__pthread_rwlock_tryrdlock, (&(NAME)), 0)
+#define __libc_rwlock_trywrlock(NAME) \
+ __libc_maybe_call (__pthread_rwlock_trywrlock, (&(NAME)), 0)
+
+#define __rtld_lock_trylock_recursive(NAME) \
+ __libc_maybe_call (__pthread_mutex_trylock, (&(NAME).mutex), 0)
+
+/* Unlock the named lock variable. */
+#if IS_IN (libc) || IS_IN (libpthread)
+# define __libc_lock_unlock(NAME) \
+ lll_unlock (NAME, LLL_PRIVATE)
+#else
+# define __libc_lock_unlock(NAME) \
+ __libc_maybe_call (__pthread_mutex_unlock, (&(NAME)), 0)
+#endif
+#define __libc_rwlock_unlock(NAME) \
+ __libc_ptf_call (__pthread_rwlock_unlock, (&(NAME)), 0)
+
+#ifdef SHARED
+# define __rtld_lock_default_lock_recursive(lock) \
+ ++((pthread_mutex_t *)(lock))->__data.__count;
+
+# define __rtld_lock_default_unlock_recursive(lock) \
+ --((pthread_mutex_t *)(lock))->__data.__count;
+
+# define __rtld_lock_lock_recursive(NAME) \
+ GL(dl_rtld_lock_recursive) (&(NAME).mutex)
+
+# define __rtld_lock_unlock_recursive(NAME) \
+ GL(dl_rtld_unlock_recursive) (&(NAME).mutex)
+#else
+# define __rtld_lock_lock_recursive(NAME) \
+ __libc_maybe_call (__pthread_mutex_lock, (&(NAME).mutex), 0)
+
+# define __rtld_lock_unlock_recursive(NAME) \
+ __libc_maybe_call (__pthread_mutex_unlock, (&(NAME).mutex), 0)
+#endif
+
+/* Define once control variable. */
+#if PTHREAD_ONCE_INIT == 0
+/* Special case for static variables where we can avoid the initialization
+ if it is zero. */
+# define __libc_once_define(CLASS, NAME) \
+ CLASS pthread_once_t NAME
+#else
+# define __libc_once_define(CLASS, NAME) \
+ CLASS pthread_once_t NAME = PTHREAD_ONCE_INIT
+#endif
+
+/* Call handler iff the first call. */
+#define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
+ do { \
+ if (PTFAVAIL (__pthread_once)) \
+ __libc_ptf_call_always (__pthread_once, (&(ONCE_CONTROL), \
+ INIT_FUNCTION)); \
+ else if ((ONCE_CONTROL) == PTHREAD_ONCE_INIT) { \
+ INIT_FUNCTION (); \
+ (ONCE_CONTROL) |= 2; \
+ } \
+ } while (0)
+
+/* Get once control variable. */
+#define __libc_once_get(ONCE_CONTROL) ((ONCE_CONTROL) != PTHREAD_ONCE_INIT)
+
+/* Note that for I/O cleanup handling we are using the old-style
+ cancel handling. It does not have to be integrated with C++ snce
+ no C++ code is called in the middle. The old-style handling is
+ faster and the support is not going away. */
+extern void _pthread_cleanup_push (struct _pthread_cleanup_buffer *buffer,
+ void (*routine) (void *), void *arg);
+extern void _pthread_cleanup_pop (struct _pthread_cleanup_buffer *buffer,
+ int execute);
+extern void _pthread_cleanup_push_defer (struct _pthread_cleanup_buffer *buffer,
+ void (*routine) (void *), void *arg);
+extern void _pthread_cleanup_pop_restore (struct _pthread_cleanup_buffer *buffer,
+ int execute);
+
+/* Sometimes we have to exit the block in the middle. */
+#define __libc_cleanup_end(DOIT) \
+ if (_avail) { \
+ __libc_ptf_call_always (_pthread_cleanup_pop_restore, (&_buffer, DOIT));\
+ } else if (DOIT) \
+ _buffer.__routine (_buffer.__arg)
+
+
+/* Normal cleanup handling, based on C cleanup attribute. */
+__extern_inline void
+__libc_cleanup_routine (struct __pthread_cleanup_frame *f)
+{
+ if (f->__do_it)
+ f->__cancel_routine (f->__cancel_arg);
+}
+
+#define __libc_cleanup_push(fct, arg) \
+ do { \
+ struct __pthread_cleanup_frame __clframe \
+ __attribute__ ((__cleanup__ (__libc_cleanup_routine))) \
+ = { .__cancel_routine = (fct), .__cancel_arg = (arg), \
+ .__do_it = 1 };
+
+#define __libc_cleanup_pop(execute) \
+ __clframe.__do_it = (execute); \
+ } while (0)
+
+
+/* Create thread-specific key. */
+#define __libc_key_create(KEY, DESTRUCTOR) \
+ __libc_ptf_call (__pthread_key_create, (KEY, DESTRUCTOR), 1)
+
+/* Get thread-specific data. */
+#define __libc_getspecific(KEY) \
+ __libc_ptf_call (__pthread_getspecific, (KEY), NULL)
+
+/* Set thread-specific data. */
+#define __libc_setspecific(KEY, VALUE) \
+ __libc_ptf_call (__pthread_setspecific, (KEY, VALUE), 0)
+
+
+/* Register handlers to execute before and after `fork'. Note that the
+ last parameter is NULL. The handlers registered by the libc are
+ never removed so this is OK. */
+#define __libc_atfork(PREPARE, PARENT, CHILD) \
+ __register_atfork (PREPARE, PARENT, CHILD, NULL)
+extern int __register_atfork (void (*__prepare) (void),
+ void (*__parent) (void),
+ void (*__child) (void),
+ void *__dso_handle);
+
+/* Functions that are used by this file and are internal to the GNU C
+ library. */
+
+extern int __pthread_mutex_init (pthread_mutex_t *__mutex,
+ const pthread_mutexattr_t *__mutex_attr);
+
+extern int __pthread_mutex_destroy (pthread_mutex_t *__mutex);
+
+extern int __pthread_mutex_trylock (pthread_mutex_t *__mutex);
+
+extern int __pthread_mutex_lock (pthread_mutex_t *__mutex);
+
+extern int __pthread_mutex_unlock (pthread_mutex_t *__mutex);
+
+extern int __pthread_mutexattr_init (pthread_mutexattr_t *__attr);
+
+extern int __pthread_mutexattr_destroy (pthread_mutexattr_t *__attr);
+
+extern int __pthread_mutexattr_settype (pthread_mutexattr_t *__attr,
+ int __kind);
+
+extern int __pthread_rwlock_init (pthread_rwlock_t *__rwlock,
+ const pthread_rwlockattr_t *__attr);
+
+extern int __pthread_rwlock_destroy (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_rwlock_rdlock (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_rwlock_tryrdlock (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_rwlock_wrlock (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_rwlock_trywrlock (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_rwlock_unlock (pthread_rwlock_t *__rwlock);
+
+extern int __pthread_key_create (pthread_key_t *__key,
+ void (*__destr_function) (void *));
+
+extern int __pthread_setspecific (pthread_key_t __key,
+ const void *__pointer);
+
+extern void *__pthread_getspecific (pthread_key_t __key);
+
+extern int __pthread_once (pthread_once_t *__once_control,
+ void (*__init_routine) (void));
+
+extern int __pthread_atfork (void (*__prepare) (void),
+ void (*__parent) (void),
+ void (*__child) (void));
+
+
+
+/* Make the pthread functions weak so that we can elide them from
+ single-threaded processes. */
+#ifndef __NO_WEAK_PTHREAD_ALIASES
+# ifdef weak_extern
+weak_extern (__pthread_mutex_init)
+weak_extern (__pthread_mutex_destroy)
+weak_extern (__pthread_mutex_lock)
+weak_extern (__pthread_mutex_trylock)
+weak_extern (__pthread_mutex_unlock)
+weak_extern (__pthread_mutexattr_init)
+weak_extern (__pthread_mutexattr_destroy)
+weak_extern (__pthread_mutexattr_settype)
+weak_extern (__pthread_rwlock_init)
+weak_extern (__pthread_rwlock_destroy)
+weak_extern (__pthread_rwlock_rdlock)
+weak_extern (__pthread_rwlock_tryrdlock)
+weak_extern (__pthread_rwlock_wrlock)
+weak_extern (__pthread_rwlock_trywrlock)
+weak_extern (__pthread_rwlock_unlock)
+weak_extern (__pthread_key_create)
+weak_extern (__pthread_setspecific)
+weak_extern (__pthread_getspecific)
+weak_extern (__pthread_once)
+weak_extern (__pthread_initialize)
+weak_extern (__pthread_atfork)
+weak_extern (_pthread_cleanup_push_defer)
+weak_extern (_pthread_cleanup_pop_restore)
+weak_extern (pthread_setcancelstate)
+# else
+# pragma weak __pthread_mutex_init
+# pragma weak __pthread_mutex_destroy
+# pragma weak __pthread_mutex_lock
+# pragma weak __pthread_mutex_trylock
+# pragma weak __pthread_mutex_unlock
+# pragma weak __pthread_mutexattr_init
+# pragma weak __pthread_mutexattr_destroy
+# pragma weak __pthread_mutexattr_settype
+# pragma weak __pthread_rwlock_destroy
+# pragma weak __pthread_rwlock_rdlock
+# pragma weak __pthread_rwlock_tryrdlock
+# pragma weak __pthread_rwlock_wrlock
+# pragma weak __pthread_rwlock_trywrlock
+# pragma weak __pthread_rwlock_unlock
+# pragma weak __pthread_key_create
+# pragma weak __pthread_setspecific
+# pragma weak __pthread_getspecific
+# pragma weak __pthread_once
+# pragma weak __pthread_initialize
+# pragma weak __pthread_atfork
+# pragma weak _pthread_cleanup_push_defer
+# pragma weak _pthread_cleanup_pop_restore
+# pragma weak pthread_setcancelstate
+# endif
+#endif
+
+#endif /* libc-lockP.h */