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Diffstat (limited to 'sysdeps/nptl/libc-lock.h')
| -rw-r--r-- | sysdeps/nptl/libc-lock.h | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/sysdeps/nptl/libc-lock.h b/sysdeps/nptl/libc-lock.h new file mode 100644 index 0000000000..db11456b38 --- /dev/null +++ b/sysdeps/nptl/libc-lock.h @@ -0,0 +1,187 @@ +/* libc-internal interface for mutex locks. NPTL version. + Copyright (C) 1996-2016 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_LOCK_H +#define _LIBC_LOCK_H 1 + +#include <pthread.h> +#define __need_NULL +#include <stddef.h> + + +/* Mutex type. */ +#if defined _LIBC || defined _IO_MTSAFE_IO +# if (!IS_IN (libc) && !IS_IN (libpthread)) || !defined _LIBC +typedef struct { pthread_mutex_t mutex; } __libc_lock_recursive_t; +# else +typedef struct { int lock; int cnt; void *owner; } __libc_lock_recursive_t; +# endif +#else +typedef struct __libc_lock_recursive_opaque__ __libc_lock_recursive_t; +#endif + +/* 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_recursive(CLASS,NAME) \ + CLASS __libc_lock_recursive_t NAME; + +/* Define an initialized recursive lock variable NAME with storage + class CLASS. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +# define __libc_lock_define_initialized_recursive(CLASS, NAME) \ + CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER; +# define _LIBC_LOCK_RECURSIVE_INITIALIZER \ + { LLL_LOCK_INITIALIZER, 0, NULL } +#else +# define __libc_lock_define_initialized_recursive(CLASS,NAME) \ + CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER; +# define _LIBC_LOCK_RECURSIVE_INITIALIZER \ + {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP} +#endif + +/* Initialize a recursive mutex. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +# define __libc_lock_init_recursive(NAME) \ + ((void) ((NAME) = (__libc_lock_recursive_t) _LIBC_LOCK_RECURSIVE_INITIALIZER)) +#else +# define __libc_lock_init_recursive(NAME) \ + do { \ + if (__pthread_mutex_init != NULL) \ + { \ + pthread_mutexattr_t __attr; \ + __pthread_mutexattr_init (&__attr); \ + __pthread_mutexattr_settype (&__attr, PTHREAD_MUTEX_RECURSIVE_NP); \ + __pthread_mutex_init (&(NAME).mutex, &__attr); \ + __pthread_mutexattr_destroy (&__attr); \ + } \ + } while (0) +#endif + +/* Finalize recursive named lock. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +# define __libc_lock_fini_recursive(NAME) ((void) 0) +#else +# define __libc_lock_fini_recursive(NAME) \ + __libc_maybe_call (__pthread_mutex_destroy, (&(NAME).mutex), 0) +#endif + +/* Lock the recursive named lock variable. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +# define __libc_lock_lock_recursive(NAME) \ + do { \ + void *self = THREAD_SELF; \ + if ((NAME).owner != self) \ + { \ + lll_lock ((NAME).lock, LLL_PRIVATE); \ + (NAME).owner = self; \ + } \ + ++(NAME).cnt; \ + } while (0) +#else +# define __libc_lock_lock_recursive(NAME) \ + __libc_maybe_call (__pthread_mutex_lock, (&(NAME).mutex), 0) +#endif + +/* Try to lock the recursive named lock variable. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +# define __libc_lock_trylock_recursive(NAME) \ + ({ \ + int result = 0; \ + void *self = THREAD_SELF; \ + if ((NAME).owner != self) \ + { \ + if (lll_trylock ((NAME).lock) == 0) \ + { \ + (NAME).owner = self; \ + (NAME).cnt = 1; \ + } \ + else \ + result = EBUSY; \ + } \ + else \ + ++(NAME).cnt; \ + result; \ + }) +#else +# define __libc_lock_trylock_recursive(NAME) \ + __libc_maybe_call (__pthread_mutex_trylock, (&(NAME).mutex), 0) +#endif + +/* Unlock the recursive named lock variable. */ +#if defined _LIBC && (IS_IN (libc) || IS_IN (libpthread)) +/* We do no error checking here. */ +# define __libc_lock_unlock_recursive(NAME) \ + do { \ + if (--(NAME).cnt == 0) \ + { \ + (NAME).owner = NULL; \ + lll_unlock ((NAME).lock, LLL_PRIVATE); \ + } \ + } while (0) +#else +# define __libc_lock_unlock_recursive(NAME) \ + __libc_maybe_call (__pthread_mutex_unlock, (&(NAME).mutex), 0) +#endif + +/* Note that for I/O cleanup handling we are using the old-style + cancel handling. It does not have to be integrated with C++ since + 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_defer (struct _pthread_cleanup_buffer *buffer, + void (*routine) (void *), void *arg); +extern void _pthread_cleanup_pop_restore (struct _pthread_cleanup_buffer *buffer, + int execute); + +/* Start critical region with cleanup. */ +#define __libc_cleanup_region_start(DOIT, FCT, ARG) \ + { struct _pthread_cleanup_buffer _buffer; \ + int _avail; \ + if (DOIT) { \ + _avail = PTFAVAIL (_pthread_cleanup_push_defer); \ + if (_avail) { \ + __libc_ptf_call_always (_pthread_cleanup_push_defer, (&_buffer, FCT, \ + ARG)); \ + } else { \ + _buffer.__routine = (FCT); \ + _buffer.__arg = (ARG); \ + } \ + } else { \ + _avail = 0; \ + } + +/* End critical region with cleanup. */ +#define __libc_cleanup_region_end(DOIT) \ + if (_avail) { \ + __libc_ptf_call_always (_pthread_cleanup_pop_restore, (&_buffer, DOIT));\ + } else if (DOIT) \ + _buffer.__routine (_buffer.__arg); \ + } + + +/* Hide the definitions which are only supposed to be used inside libc in + a separate file. This file is not present in the installation! */ +#ifdef _LIBC +# include "libc-lockP.h" +#endif + +#endif /* libc-lock.h */ |