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author | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:24:06 +0300 |
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committer | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:41:34 +0300 |
commit | e0e3e1717e3d33762ce61950504f9637a6e669ed (patch) | |
tree | bca3ff6939b10ed60c3d5c12439963a1146b9711 /contrib/tools/python/src/Python/thread_pthread.h | |
parent | 38f2c5852db84c7b4d83adfcb009eb61541d1ccd (diff) | |
download | ydb-e0e3e1717e3d33762ce61950504f9637a6e669ed.tar.gz |
add ydb deps
Diffstat (limited to 'contrib/tools/python/src/Python/thread_pthread.h')
-rw-r--r-- | contrib/tools/python/src/Python/thread_pthread.h | 553 |
1 files changed, 553 insertions, 0 deletions
diff --git a/contrib/tools/python/src/Python/thread_pthread.h b/contrib/tools/python/src/Python/thread_pthread.h new file mode 100644 index 0000000000..6d4b3b389f --- /dev/null +++ b/contrib/tools/python/src/Python/thread_pthread.h @@ -0,0 +1,553 @@ + +/* Posix threads interface */ + +#include <stdlib.h> +#include <string.h> +#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR) +#define destructor xxdestructor +#endif +#include <pthread.h> +#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR) +#undef destructor +#endif +#include <signal.h> + +/* The POSIX spec requires that use of pthread_attr_setstacksize + be conditional on _POSIX_THREAD_ATTR_STACKSIZE being defined. */ +#ifdef _POSIX_THREAD_ATTR_STACKSIZE +#ifndef THREAD_STACK_SIZE +#define THREAD_STACK_SIZE 0 /* use default stack size */ +#endif + +#if (defined(__APPLE__) || defined(__FreeBSD__)) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0 + /* The default stack size for new threads on OSX is small enough that + * we'll get hard crashes instead of 'maximum recursion depth exceeded' + * exceptions. + * + * The default stack size below is the minimal stack size where a + * simple recursive function doesn't cause a hard crash. + */ +#undef THREAD_STACK_SIZE +#define THREAD_STACK_SIZE 0x400000 +#endif +/* for safety, ensure a viable minimum stacksize */ +#define THREAD_STACK_MIN 0x8000 /* 32kB */ +#else /* !_POSIX_THREAD_ATTR_STACKSIZE */ +#ifdef THREAD_STACK_SIZE +#error "THREAD_STACK_SIZE defined but _POSIX_THREAD_ATTR_STACKSIZE undefined" +#endif +#endif + +/* The POSIX spec says that implementations supporting the sem_* + family of functions must indicate this by defining + _POSIX_SEMAPHORES. */ +#ifdef _POSIX_SEMAPHORES +/* On FreeBSD 4.x, _POSIX_SEMAPHORES is defined empty, so + we need to add 0 to make it work there as well. */ +#if (_POSIX_SEMAPHORES+0) == -1 +#define HAVE_BROKEN_POSIX_SEMAPHORES +#else +#include <semaphore.h> +#include <errno.h> +#endif +#endif + +/* Before FreeBSD 5.4, system scope threads was very limited resource + in default setting. So the process scope is preferred to get + enough number of threads to work. */ +#ifdef __FreeBSD__ +#include <osreldate.h> +#if __FreeBSD_version >= 500000 && __FreeBSD_version < 504101 +#undef PTHREAD_SYSTEM_SCHED_SUPPORTED +#endif +#endif + +#if !defined(pthread_attr_default) +# define pthread_attr_default ((pthread_attr_t *)NULL) +#endif +#if !defined(pthread_mutexattr_default) +# define pthread_mutexattr_default ((pthread_mutexattr_t *)NULL) +#endif +#if !defined(pthread_condattr_default) +# define pthread_condattr_default ((pthread_condattr_t *)NULL) +#endif + + +/* Whether or not to use semaphores directly rather than emulating them with + * mutexes and condition variables: + */ +#if defined(_POSIX_SEMAPHORES) && !defined(HAVE_BROKEN_POSIX_SEMAPHORES) +# define USE_SEMAPHORES +#else +# undef USE_SEMAPHORES +#endif + + +/* On platforms that don't use standard POSIX threads pthread_sigmask() + * isn't present. DEC threads uses sigprocmask() instead as do most + * other UNIX International compliant systems that don't have the full + * pthread implementation. + */ +#if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK) +# define SET_THREAD_SIGMASK pthread_sigmask +#else +# define SET_THREAD_SIGMASK sigprocmask +#endif + + +/* A pthread mutex isn't sufficient to model the Python lock type + * because, according to Draft 5 of the docs (P1003.4a/D5), both of the + * following are undefined: + * -> a thread tries to lock a mutex it already has locked + * -> a thread tries to unlock a mutex locked by a different thread + * pthread mutexes are designed for serializing threads over short pieces + * of code anyway, so wouldn't be an appropriate implementation of + * Python's locks regardless. + * + * The pthread_lock struct implements a Python lock as a "locked?" bit + * and a <condition, mutex> pair. In general, if the bit can be acquired + * instantly, it is, else the pair is used to block the thread until the + * bit is cleared. 9 May 1994 tim@ksr.com + */ + +typedef struct { + char locked; /* 0=unlocked, 1=locked */ + /* a <cond, mutex> pair to handle an acquire of a locked lock */ + pthread_cond_t lock_released; + pthread_mutex_t mut; +} pthread_lock; + +#define CHECK_STATUS(name) if (status != 0) { perror(name); error = 1; } + +/* + * Initialization. + */ + +#ifdef _HAVE_BSDI +static +void _noop(void) +{ +} + +static void +PyThread__init_thread(void) +{ + /* DO AN INIT BY STARTING THE THREAD */ + static int dummy = 0; + pthread_t thread1; + pthread_create(&thread1, NULL, (void *) _noop, &dummy); + pthread_join(thread1, NULL); +} + +#else /* !_HAVE_BSDI */ + +static void +PyThread__init_thread(void) +{ +#if defined(_AIX) && defined(__GNUC__) + extern void pthread_init(void); + pthread_init(); +#endif +} + +#endif /* !_HAVE_BSDI */ + +/* + * Thread support. + */ + +/* bpo-33015: pythread_callback struct and pythread_wrapper() cast + "void func(void *)" to "void* func(void *)": always return NULL. + + PyThread_start_new_thread() uses "void func(void *)" type, whereas + pthread_create() requires a void* return value. */ +typedef struct { + void (*func) (void *); + void *arg; +} pythread_callback; + +static void * +pythread_wrapper(void *arg) +{ + /* copy func and func_arg and free the temporary structure */ + pythread_callback *callback = arg; + void (*func)(void *) = callback->func; + void *func_arg = callback->arg; + free(arg); + + func(func_arg); + return NULL; +} + +long +PyThread_start_new_thread(void (*func)(void *), void *arg) +{ + pthread_t th; + int status; +#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED) + pthread_attr_t attrs; +#endif +#if defined(THREAD_STACK_SIZE) + size_t tss; +#endif + + dprintf(("PyThread_start_new_thread called\n")); + if (!initialized) + PyThread_init_thread(); + +#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED) + if (pthread_attr_init(&attrs) != 0) + return -1; +#endif +#if defined(THREAD_STACK_SIZE) + tss = (_pythread_stacksize != 0) ? _pythread_stacksize + : THREAD_STACK_SIZE; + if (tss != 0) { + if (pthread_attr_setstacksize(&attrs, tss) != 0) { + pthread_attr_destroy(&attrs); + return -1; + } + } +#endif +#if defined(PTHREAD_SYSTEM_SCHED_SUPPORTED) + pthread_attr_setscope(&attrs, PTHREAD_SCOPE_SYSTEM); +#endif + + pythread_callback *callback = malloc(sizeof(pythread_callback)); + + if (callback == NULL) { + return -1; + } + + callback->func = func; + callback->arg = arg; + + status = pthread_create(&th, +#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED) + &attrs, +#else + (pthread_attr_t*)NULL, +#endif + pythread_wrapper, callback); + +#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED) + pthread_attr_destroy(&attrs); +#endif + + if (status != 0) { + free(callback); + return -1; + } + + pthread_detach(th); + +#if SIZEOF_PTHREAD_T <= SIZEOF_LONG + return (long) th; +#else + return (long) *(long *) &th; +#endif +} + +/* XXX This implementation is considered (to quote Tim Peters) "inherently + hosed" because: + - It does not guarantee the promise that a non-zero integer is returned. + - The cast to long is inherently unsafe. + - It is not clear that the 'volatile' (for AIX?) and ugly casting in the + latter return statement (for Alpha OSF/1) are any longer necessary. +*/ +long +PyThread_get_thread_ident(void) +{ + volatile pthread_t threadid; + if (!initialized) + PyThread_init_thread(); + /* Jump through some hoops for Alpha OSF/1 */ + threadid = pthread_self(); +#if SIZEOF_PTHREAD_T <= SIZEOF_LONG + return (long) threadid; +#else + return (long) *(long *) &threadid; +#endif +} + +void +PyThread_exit_thread(void) +{ + dprintf(("PyThread_exit_thread called\n")); + if (!initialized) { + exit(0); + } +} + +#ifdef USE_SEMAPHORES + +/* + * Lock support. + */ + +PyThread_type_lock +PyThread_allocate_lock(void) +{ + sem_t *lock; + int status, error = 0; + + dprintf(("PyThread_allocate_lock called\n")); + if (!initialized) + PyThread_init_thread(); + + lock = (sem_t *)malloc(sizeof(sem_t)); + + if (lock) { + status = sem_init(lock,0,1); + CHECK_STATUS("sem_init"); + + if (error) { + free((void *)lock); + lock = NULL; + } + } + + dprintf(("PyThread_allocate_lock() -> %p\n", lock)); + return (PyThread_type_lock)lock; +} + +void +PyThread_free_lock(PyThread_type_lock lock) +{ + sem_t *thelock = (sem_t *)lock; + int status, error = 0; + + (void) error; /* silence unused-but-set-variable warning */ + dprintf(("PyThread_free_lock(%p) called\n", lock)); + + if (!thelock) + return; + + status = sem_destroy(thelock); + CHECK_STATUS("sem_destroy"); + + free((void *)thelock); +} + +/* + * As of February 2002, Cygwin thread implementations mistakenly report error + * codes in the return value of the sem_ calls (like the pthread_ functions). + * Correct implementations return -1 and put the code in errno. This supports + * either. + */ +static int +fix_status(int status) +{ + return (status == -1) ? errno : status; +} + +int +PyThread_acquire_lock(PyThread_type_lock lock, int waitflag) +{ + int success; + sem_t *thelock = (sem_t *)lock; + int status, error = 0; + + (void) error; /* silence unused-but-set-variable warning */ + dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag)); + + do { + if (waitflag) + status = fix_status(sem_wait(thelock)); + else + status = fix_status(sem_trywait(thelock)); + } while (status == EINTR); /* Retry if interrupted by a signal */ + + if (waitflag) { + CHECK_STATUS("sem_wait"); + } else if (status != EAGAIN) { + CHECK_STATUS("sem_trywait"); + } + + success = (status == 0) ? 1 : 0; + + dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success)); + return success; +} + +void +PyThread_release_lock(PyThread_type_lock lock) +{ + sem_t *thelock = (sem_t *)lock; + int status, error = 0; + + (void) error; /* silence unused-but-set-variable warning */ + dprintf(("PyThread_release_lock(%p) called\n", lock)); + + status = sem_post(thelock); + CHECK_STATUS("sem_post"); +} + +#else /* USE_SEMAPHORES */ + +/* + * Lock support. + */ +PyThread_type_lock +PyThread_allocate_lock(void) +{ + pthread_lock *lock; + int status, error = 0; + + dprintf(("PyThread_allocate_lock called\n")); + if (!initialized) + PyThread_init_thread(); + + lock = (pthread_lock *) malloc(sizeof(pthread_lock)); + if (lock) { + memset((void *)lock, '\0', sizeof(pthread_lock)); + lock->locked = 0; + + status = pthread_mutex_init(&lock->mut, + pthread_mutexattr_default); + CHECK_STATUS("pthread_mutex_init"); + + status = pthread_cond_init(&lock->lock_released, + pthread_condattr_default); + CHECK_STATUS("pthread_cond_init"); + + if (error) { + free((void *)lock); + lock = 0; + } + } + + dprintf(("PyThread_allocate_lock() -> %p\n", lock)); + return (PyThread_type_lock) lock; +} + +void +PyThread_free_lock(PyThread_type_lock lock) +{ + pthread_lock *thelock = (pthread_lock *)lock; + int status, error = 0; + + (void) error; /* silence unused-but-set-variable warning */ + dprintf(("PyThread_free_lock(%p) called\n", lock)); + + status = pthread_mutex_destroy( &thelock->mut ); + CHECK_STATUS("pthread_mutex_destroy"); + + status = pthread_cond_destroy( &thelock->lock_released ); + CHECK_STATUS("pthread_cond_destroy"); + + free((void *)thelock); +} + +int +PyThread_acquire_lock(PyThread_type_lock lock, int waitflag) +{ + int success = 0; + pthread_lock *thelock = (pthread_lock *)lock; + int status, error = 0; + + dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag)); + + if (waitflag) { + status = pthread_mutex_lock( &thelock->mut ); + CHECK_STATUS("pthread_mutex_lock[1]"); + } + else { + status = pthread_mutex_trylock( &thelock->mut ); + if (status != EBUSY) + CHECK_STATUS("pthread_mutex_trylock[1]"); + } + if (status == 0) { + success = thelock->locked == 0; + + if ( !success && waitflag ) { + /* continue trying until we get the lock */ + + /* mut must be locked by me -- part of the condition + * protocol */ + while ( thelock->locked ) { + status = pthread_cond_wait(&thelock->lock_released, + &thelock->mut); + CHECK_STATUS("pthread_cond_wait"); + } + success = 1; + } + + if (success) thelock->locked = 1; + status = pthread_mutex_unlock( &thelock->mut ); + CHECK_STATUS("pthread_mutex_unlock[1]"); + } + + if (error) success = 0; + dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success)); + return success; +} + +void +PyThread_release_lock(PyThread_type_lock lock) +{ + pthread_lock *thelock = (pthread_lock *)lock; + int status, error = 0; + + (void) error; /* silence unused-but-set-variable warning */ + dprintf(("PyThread_release_lock(%p) called\n", lock)); + + status = pthread_mutex_lock( &thelock->mut ); + CHECK_STATUS("pthread_mutex_lock[3]"); + + thelock->locked = 0; + + status = pthread_mutex_unlock( &thelock->mut ); + CHECK_STATUS("pthread_mutex_unlock[3]"); + + /* wake up someone (anyone, if any) waiting on the lock */ + status = pthread_cond_signal( &thelock->lock_released ); + CHECK_STATUS("pthread_cond_signal"); +} + +#endif /* USE_SEMAPHORES */ + +/* set the thread stack size. + * Return 0 if size is valid, -1 if size is invalid, + * -2 if setting stack size is not supported. + */ +static int +_pythread_pthread_set_stacksize(size_t size) +{ +#if defined(THREAD_STACK_SIZE) + pthread_attr_t attrs; + size_t tss_min; + int rc = 0; +#endif + + /* set to default */ + if (size == 0) { + _pythread_stacksize = 0; + return 0; + } + +#if defined(THREAD_STACK_SIZE) +#if defined(PTHREAD_STACK_MIN) + tss_min = PTHREAD_STACK_MIN > THREAD_STACK_MIN ? PTHREAD_STACK_MIN + : THREAD_STACK_MIN; +#else + tss_min = THREAD_STACK_MIN; +#endif + if (size >= tss_min) { + /* validate stack size by setting thread attribute */ + if (pthread_attr_init(&attrs) == 0) { + rc = pthread_attr_setstacksize(&attrs, size); + pthread_attr_destroy(&attrs); + if (rc == 0) { + _pythread_stacksize = size; + return 0; + } + } + } + return -1; +#else + return -2; +#endif +} + +#define THREAD_SET_STACKSIZE(x) _pythread_pthread_set_stacksize(x) |