diff options
Diffstat (limited to 'lib/glthread')
| -rw-r--r-- | lib/glthread/lock.c | 42 | ||||
| -rw-r--r-- | lib/glthread/lock.h | 151 | ||||
| -rw-r--r-- | lib/glthread/once.c | 80 | ||||
| -rw-r--r-- | lib/glthread/once.h | 272 |
4 files changed, 356 insertions, 189 deletions
diff --git a/lib/glthread/lock.c b/lib/glthread/lock.c index 6661ad6a..40b2a5ee 100644 --- a/lib/glthread/lock.c +++ b/lib/glthread/lock.c @@ -240,8 +240,6 @@ glthread_recursive_lock_destroy (gl_recursive_lock_t *lock) return 0; } -/* -------------------------- gl_once_t datatype -------------------------- */ - #endif /* ========================================================================= */ @@ -698,46 +696,6 @@ glthread_recursive_lock_destroy_multithreaded (gl_recursive_lock_t *lock) # endif -/* -------------------------- gl_once_t datatype -------------------------- */ - -static const pthread_once_t fresh_once = PTHREAD_ONCE_INIT; - -int -glthread_once_singlethreaded (pthread_once_t *once_control) -{ - /* We don't know whether pthread_once_t is an integer type, a floating-point - type, a pointer type, or a structure type. */ - char *firstbyte = (char *)once_control; - if (*firstbyte == *(const char *)&fresh_once) - { - /* First time use of once_control. Invert the first byte. */ - *firstbyte = ~ *(const char *)&fresh_once; - return 1; - } - else - return 0; -} - -# if !(PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK) - -int -glthread_once_multithreaded (pthread_once_t *once_control, - void (*init_function) (void)) -{ - int err = pthread_once (once_control, init_function); - if (err == ENOSYS) - { - /* This happens on FreeBSD 11: The pthread_once function in libc returns - ENOSYS. */ - if (glthread_once_singlethreaded (once_control)) - init_function (); - return 0; - } - return err; -} - -# endif - #endif /* ========================================================================= */ diff --git a/lib/glthread/lock.h b/lib/glthread/lock.h index 2d5cb320..2b9c0f2e 100644 --- a/lib/glthread/lock.h +++ b/lib/glthread/lock.h @@ -64,13 +64,6 @@ Taking the lock: err = glthread_recursive_lock_lock (&name); Releasing the lock: err = glthread_recursive_lock_unlock (&name); De-initialization: err = glthread_recursive_lock_destroy (&name); - - Once-only execution: - Type: gl_once_t - Initializer: gl_once_define(extern, name) - Execution: gl_once (name, initfunction); - Equivalent functions with control of error handling: - Execution: err = glthread_once (&name, initfunction); */ @@ -88,17 +81,9 @@ #include <errno.h> #include <stdlib.h> -#if !defined c11_threads_in_use -# if HAVE_THREADS_H && USE_POSIX_THREADS_FROM_LIBC -# define c11_threads_in_use() 1 -# elif HAVE_THREADS_H && USE_POSIX_THREADS_WEAK -# include <threads.h> -# pragma weak thrd_exit -# define c11_threads_in_use() (thrd_exit != NULL) -# else -# define c11_threads_in_use() 0 -# endif -#endif +#include "glthread/once.h" + +/* c11_threads_in_use() is defined in glthread/once.h. */ /* ========================================================================= */ @@ -195,14 +180,6 @@ extern int glthread_recursive_lock_lock (gl_recursive_lock_t *lock); extern int glthread_recursive_lock_unlock (gl_recursive_lock_t *lock); extern int glthread_recursive_lock_destroy (gl_recursive_lock_t *lock); -/* -------------------------- gl_once_t datatype -------------------------- */ - -typedef once_flag gl_once_t; -# define gl_once_define(STORAGECLASS, NAME) \ - STORAGECLASS once_flag NAME = ONCE_FLAG_INIT; -# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ - (call_once (ONCE_CONTROL, INITFUNCTION), 0) - # ifdef __cplusplus } # endif @@ -221,80 +198,7 @@ typedef once_flag gl_once_t; extern "C" { # endif -# if PTHREAD_IN_USE_DETECTION_HARD - -/* The pthread_in_use() detection needs to be done at runtime. */ -# define pthread_in_use() \ - glthread_in_use () -extern int glthread_in_use (void); - -# endif - -# if USE_POSIX_THREADS_WEAK - -/* Use weak references to the POSIX threads library. */ - -/* Weak references avoid dragging in external libraries if the other parts - of the program don't use them. Here we use them, because we don't want - every program that uses libintl to depend on libpthread. This assumes - that libpthread would not be loaded after libintl; i.e. if libintl is - loaded first, by an executable that does not depend on libpthread, and - then a module is dynamically loaded that depends on libpthread, libintl - will not be multithread-safe. */ - -/* The way to test at runtime whether libpthread is present is to test - whether a function pointer's value, such as &pthread_mutex_init, is - non-NULL. However, some versions of GCC have a bug through which, in - PIC mode, &foo != NULL always evaluates to true if there is a direct - call to foo(...) in the same function. To avoid this, we test the - address of a function in libpthread that we don't use. */ - -# pragma weak pthread_mutex_init -# pragma weak pthread_mutex_lock -# pragma weak pthread_mutex_unlock -# pragma weak pthread_mutex_destroy -# pragma weak pthread_rwlock_init -# pragma weak pthread_rwlock_rdlock -# pragma weak pthread_rwlock_wrlock -# pragma weak pthread_rwlock_unlock -# pragma weak pthread_rwlock_destroy -# pragma weak pthread_once -# pragma weak pthread_cond_init -# pragma weak pthread_cond_wait -# pragma weak pthread_cond_signal -# pragma weak pthread_cond_broadcast -# pragma weak pthread_cond_destroy -# pragma weak pthread_mutexattr_init -# pragma weak pthread_mutexattr_settype -# pragma weak pthread_mutexattr_destroy -# pragma weak pthread_rwlockattr_init -# if __GNU_LIBRARY__ > 1 -# pragma weak pthread_rwlockattr_setkind_np -# endif -# pragma weak pthread_rwlockattr_destroy -# ifndef pthread_self -# pragma weak pthread_self -# endif - -# if !PTHREAD_IN_USE_DETECTION_HARD - /* Considering all platforms with USE_POSIX_THREADS_WEAK, only few symbols - can be used to determine whether libpthread is in use. These are: - pthread_mutexattr_gettype - pthread_rwlockattr_destroy - pthread_rwlockattr_init - */ -# pragma weak pthread_mutexattr_gettype -# define pthread_in_use() \ - (pthread_mutexattr_gettype != NULL || c11_threads_in_use ()) -# endif - -# else - -# if !PTHREAD_IN_USE_DETECTION_HARD -# define pthread_in_use() 1 -# endif - -# endif +/* pthread_in_use() is defined in glthread/once.h. */ /* -------------------------- gl_lock_t datatype -------------------------- */ @@ -510,26 +414,6 @@ extern int glthread_recursive_lock_destroy_multithreaded (gl_recursive_lock_t *l # endif -/* -------------------------- gl_once_t datatype -------------------------- */ - -typedef pthread_once_t gl_once_t; -# define gl_once_define(STORAGECLASS, NAME) \ - STORAGECLASS pthread_once_t NAME = PTHREAD_ONCE_INIT; -# if PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK -# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ - (pthread_in_use () \ - ? pthread_once (ONCE_CONTROL, INITFUNCTION) \ - : (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0)) -# else -# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ - (pthread_in_use () \ - ? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION) \ - : (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0)) -extern int glthread_once_multithreaded (pthread_once_t *once_control, - void (*init_function) (void)); -# endif -extern int glthread_once_singlethreaded (pthread_once_t *once_control); - # ifdef __cplusplus } # endif @@ -546,7 +430,6 @@ extern int glthread_once_singlethreaded (pthread_once_t *once_control); # include "windows-mutex.h" # include "windows-rwlock.h" # include "windows-recmutex.h" -# include "windows-once.h" # ifdef __cplusplus extern "C" { @@ -619,14 +502,6 @@ typedef glwthread_recmutex_t gl_recursive_lock_t; # define glthread_recursive_lock_destroy(LOCK) \ glwthread_recmutex_destroy (LOCK) -/* -------------------------- gl_once_t datatype -------------------------- */ - -typedef glwthread_once_t gl_once_t; -# define gl_once_define(STORAGECLASS, NAME) \ - STORAGECLASS gl_once_t NAME = GLWTHREAD_ONCE_INIT; -# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ - (glwthread_once (ONCE_CONTROL, INITFUNCTION), 0) - # ifdef __cplusplus } # endif @@ -670,14 +545,6 @@ typedef int gl_recursive_lock_t; # define glthread_recursive_lock_unlock(NAME) 0 # define glthread_recursive_lock_destroy(NAME) 0 -/* -------------------------- gl_once_t datatype -------------------------- */ - -typedef int gl_once_t; -# define gl_once_define(STORAGECLASS, NAME) \ - STORAGECLASS gl_once_t NAME = 0; -# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ - (*(ONCE_CONTROL) == 0 ? (*(ONCE_CONTROL) = ~ 0, INITFUNCTION (), 0) : 0) - #endif /* ========================================================================= */ @@ -784,16 +651,6 @@ typedef int gl_once_t; } \ while (0) -/* -------------------------- gl_once_t datatype -------------------------- */ - -#define gl_once(NAME, INITFUNCTION) \ - do \ - { \ - if (glthread_once (&NAME, INITFUNCTION)) \ - abort (); \ - } \ - while (0) - /* ========================================================================= */ #endif /* _LOCK_H */ diff --git a/lib/glthread/once.c b/lib/glthread/once.c new file mode 100644 index 00000000..869ba3ba --- /dev/null +++ b/lib/glthread/once.c @@ -0,0 +1,80 @@ +/* Once-only initialization in multithreaded situations. + Copyright (C) 2005-2024 Free Software Foundation, Inc. + + This file 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. + + This file 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 this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible <bruno@clisp.org>, 2005. + Based on GCC's gthr-posix.h, gthr-posix95.h. */ + +#include <config.h> + +#include "glthread/once.h" + +/* ========================================================================= */ + +#if USE_ISOC_THREADS || USE_ISOC_AND_POSIX_THREADS + +#endif + +/* ========================================================================= */ + +#if USE_POSIX_THREADS + +static const pthread_once_t fresh_once = PTHREAD_ONCE_INIT; + +int +glthread_once_singlethreaded (pthread_once_t *once_control) +{ + /* We don't know whether pthread_once_t is an integer type, a floating-point + type, a pointer type, or a structure type. */ + char *firstbyte = (char *)once_control; + if (*firstbyte == *(const char *)&fresh_once) + { + /* First time use of once_control. Invert the first byte. */ + *firstbyte = ~ *(const char *)&fresh_once; + return 1; + } + else + return 0; +} + +# if !(PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK) + +int +glthread_once_multithreaded (pthread_once_t *once_control, + void (*init_function) (void)) +{ + int err = pthread_once (once_control, init_function); + if (err == ENOSYS) + { + /* This happens on FreeBSD 11: The pthread_once function in libc returns + ENOSYS. */ + if (glthread_once_singlethreaded (once_control)) + init_function (); + return 0; + } + return err; +} + +# endif + +#endif + +/* ========================================================================= */ + +#if USE_WINDOWS_THREADS + +#endif + +/* ========================================================================= */ diff --git a/lib/glthread/once.h b/lib/glthread/once.h new file mode 100644 index 00000000..2452f88d --- /dev/null +++ b/lib/glthread/once.h @@ -0,0 +1,272 @@ +/* Once-only initialization in multithreaded situations. + Copyright (C) 2005-2024 Free Software Foundation, Inc. + + This file 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. + + This file 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 this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by Bruno Haible <bruno@clisp.org>, 2005. + Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-win32.h. */ + +/* This file contains once-only initialization primitives for use with a given + thread library. + It does not contain primitives for creating threads or for other + synchronization primitives. + + Once-only execution: + Type: gl_once_t + Initializer: gl_once_define(extern, name) + Execution: gl_once (name, initfunction); + Equivalent functions with control of error handling: + Execution: err = glthread_once (&name, initfunction); +*/ + + +#ifndef _ONCE_H +#define _ONCE_H + +/* This file uses HAVE_THREADS_H. */ +#if !_GL_CONFIG_H_INCLUDED + #error "Please include config.h first." +#endif + +#include <errno.h> +#include <stdlib.h> + +#if !defined c11_threads_in_use +# if HAVE_THREADS_H && USE_POSIX_THREADS_FROM_LIBC +# define c11_threads_in_use() 1 +# elif HAVE_THREADS_H && USE_POSIX_THREADS_WEAK +# include <threads.h> +# pragma weak thrd_exit +# define c11_threads_in_use() (thrd_exit != NULL) +# else +# define c11_threads_in_use() 0 +# endif +#endif + +/* ========================================================================= */ + +#if USE_ISOC_THREADS || USE_ISOC_AND_POSIX_THREADS + +/* Use the ISO C threads library. */ + +# include <threads.h> + +# ifdef __cplusplus +extern "C" { +# endif + +/* -------------------------- gl_once_t datatype -------------------------- */ + +typedef once_flag gl_once_t; +# define gl_once_define(STORAGECLASS, NAME) \ + STORAGECLASS once_flag NAME = ONCE_FLAG_INIT; +# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ + (call_once (ONCE_CONTROL, INITFUNCTION), 0) + +# ifdef __cplusplus +} +# endif + +#endif + +/* ========================================================================= */ + +#if USE_POSIX_THREADS + +/* Use the POSIX threads library. */ + +# include <pthread.h> + +# ifdef __cplusplus +extern "C" { +# endif + +# if PTHREAD_IN_USE_DETECTION_HARD + +/* The pthread_in_use() detection needs to be done at runtime. */ +# define pthread_in_use() \ + glthread_in_use () +extern int glthread_in_use (void); + +# endif + +# if USE_POSIX_THREADS_WEAK + +/* Use weak references to the POSIX threads library. */ + +/* Weak references avoid dragging in external libraries if the other parts + of the program don't use them. Here we use them, because we don't want + every program that uses libintl to depend on libpthread. This assumes + that libpthread would not be loaded after libintl; i.e. if libintl is + loaded first, by an executable that does not depend on libpthread, and + then a module is dynamically loaded that depends on libpthread, libintl + will not be multithread-safe. */ + +/* The way to test at runtime whether libpthread is present is to test + whether a function pointer's value, such as &pthread_mutex_init, is + non-NULL. However, some versions of GCC have a bug through which, in + PIC mode, &foo != NULL always evaluates to true if there is a direct + call to foo(...) in the same function. To avoid this, we test the + address of a function in libpthread that we don't use. */ + +# pragma weak pthread_mutex_init +# pragma weak pthread_mutex_lock +# pragma weak pthread_mutex_unlock +# pragma weak pthread_mutex_destroy +/* Work around clang bug <https://github.com/llvm/llvm-project/issues/104670> */ +# ifndef pthread_rwlock_init +# pragma weak pthread_rwlock_init +# endif +# pragma weak pthread_rwlock_rdlock +# pragma weak pthread_rwlock_wrlock +# pragma weak pthread_rwlock_unlock +# pragma weak pthread_rwlock_destroy +# pragma weak pthread_once +# pragma weak pthread_cond_init +# pragma weak pthread_cond_wait +# pragma weak pthread_cond_signal +# pragma weak pthread_cond_broadcast +# pragma weak pthread_cond_destroy +# pragma weak pthread_mutexattr_init +# pragma weak pthread_mutexattr_settype +# pragma weak pthread_mutexattr_destroy +/* Work around clang bug <https://github.com/llvm/llvm-project/issues/104670> */ +# ifndef pthread_rwlockattr_init +# pragma weak pthread_rwlockattr_init +# endif +# if __GNU_LIBRARY__ > 1 +# pragma weak pthread_rwlockattr_setkind_np +# endif +# pragma weak pthread_rwlockattr_destroy +# ifndef pthread_self +# pragma weak pthread_self +# endif + +# if !PTHREAD_IN_USE_DETECTION_HARD + /* Considering all platforms with USE_POSIX_THREADS_WEAK, only few symbols + can be used to determine whether libpthread is in use. These are: + pthread_mutexattr_gettype + pthread_rwlockattr_destroy + pthread_rwlockattr_init + */ +# pragma weak pthread_mutexattr_gettype +# define pthread_in_use() \ + (pthread_mutexattr_gettype != NULL || c11_threads_in_use ()) +# endif + +# else + +# if !PTHREAD_IN_USE_DETECTION_HARD +# define pthread_in_use() 1 +# endif + +# endif + +/* -------------------------- gl_once_t datatype -------------------------- */ + +typedef pthread_once_t gl_once_t; +# define gl_once_define(STORAGECLASS, NAME) \ + STORAGECLASS pthread_once_t NAME = PTHREAD_ONCE_INIT; +# if PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK +# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ + (pthread_in_use () \ + ? pthread_once (ONCE_CONTROL, INITFUNCTION) \ + : (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0)) +# else +# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ + (pthread_in_use () \ + ? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION) \ + : (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0)) +extern int glthread_once_multithreaded (pthread_once_t *once_control, + void (*init_function) (void)); +# endif +extern int glthread_once_singlethreaded (pthread_once_t *once_control); + +# ifdef __cplusplus +} +# endif + +#endif + +/* ========================================================================= */ + +#if USE_WINDOWS_THREADS + +# define WIN32_LEAN_AND_MEAN /* avoid including junk */ +# include <windows.h> + +# include "windows-once.h" + +# ifdef __cplusplus +extern "C" { +# endif + +/* We can use CRITICAL_SECTION directly, rather than the native Windows Event, + Mutex, Semaphore types, because + - we need only to synchronize inside a single process (address space), + not inter-process locking, + - we don't need to support trylock operations. (TryEnterCriticalSection + does not work on Windows 95/98/ME. Packages that need trylock usually + define their own mutex type.) */ + +/* There is no way to statically initialize a CRITICAL_SECTION. It needs + to be done lazily, once only. For this we need spinlocks. */ + +/* -------------------------- gl_once_t datatype -------------------------- */ + +typedef glwthread_once_t gl_once_t; +# define gl_once_define(STORAGECLASS, NAME) \ + STORAGECLASS gl_once_t NAME = GLWTHREAD_ONCE_INIT; +# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ + (glwthread_once (ONCE_CONTROL, INITFUNCTION), 0) + +# ifdef __cplusplus +} +# endif + +#endif + +/* ========================================================================= */ + +#if !(USE_ISOC_THREADS || USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS || USE_WINDOWS_THREADS) + +/* Provide dummy implementation if threads are not supported. */ + +/* -------------------------- gl_once_t datatype -------------------------- */ + +typedef int gl_once_t; +# define gl_once_define(STORAGECLASS, NAME) \ + STORAGECLASS gl_once_t NAME = 0; +# define glthread_once(ONCE_CONTROL, INITFUNCTION) \ + (*(ONCE_CONTROL) == 0 ? (*(ONCE_CONTROL) = ~ 0, INITFUNCTION (), 0) : 0) + +#endif + +/* ========================================================================= */ + +/* Macros with built-in error handling. */ + +/* -------------------------- gl_once_t datatype -------------------------- */ + +#define gl_once(NAME, INITFUNCTION) \ + do \ + { \ + if (glthread_once (&NAME, INITFUNCTION)) \ + abort (); \ + } \ + while (0) + +/* ========================================================================= */ + +#endif /* _ONCE_H */ |