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/*
* Copyright 2015 The Emscripten Authors. All rights reserved.
* Emscripten is available under two separate licenses, the MIT license and the
* University of Illinois/NCSA Open Source License. Both these licenses can be
* found in the LICENSE file.
*/
#define _GNU_SOURCE
#include "../internal/libc.h"
#include "../internal/pthread_impl.h"
#include <assert.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <sys/time.h>
#include <termios.h>
#include <threads.h>
#include <unistd.h>
#include <utime.h>
#include <emscripten.h>
#include <emscripten/proxying.h>
#include <emscripten/stack.h>
#include <emscripten/threading.h>
#include "threading_internal.h"
#include "emscripten_internal.h"
int emscripten_pthread_attr_gettransferredcanvases(const pthread_attr_t* a, const char** str) {
*str = a->_a_transferredcanvases;
return 0;
}
int emscripten_pthread_attr_settransferredcanvases(pthread_attr_t* a, const char* str) {
a->_a_transferredcanvases = str;
return 0;
}
int sched_get_priority_max(int policy) {
// Web workers do not actually support prioritizing threads,
// but mimic values that Linux apparently reports, see
// http://man7.org/linux/man-pages/man2/sched_get_priority_min.2.html
if (policy == SCHED_FIFO || policy == SCHED_RR)
return 99;
else
return 0;
}
int sched_get_priority_min(int policy) {
// Web workers do not actually support prioritizing threads,
// but mimic values that Linux apparently reports, see
// http://man7.org/linux/man-pages/man2/sched_get_priority_min.2.html
if (policy == SCHED_FIFO || policy == SCHED_RR)
return 1;
else
return 0;
}
int pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *restrict attr, int *restrict prioceiling)
{
// Not supported either in Emscripten or musl, return a faked value.
if (prioceiling) *prioceiling = 99;
return 0;
}
int pthread_mutexattr_setprioceiling(pthread_mutexattr_t *attr, int prioceiling)
{
// Not supported either in Emscripten or musl, return an error.
return EPERM;
}
static uint32_t dummyZeroAddress = 0;
void emscripten_thread_sleep(double msecs) {
double now = emscripten_get_now();
double target = now + msecs;
// If we have less than this many msecs left to wait, busy spin that instead.
double min_ms_slice_to_sleep = 0.1;
// runtime thread may need to run proxied calls, so sleep in very small slices to be responsive.
double max_ms_slice_to_sleep = emscripten_is_main_runtime_thread() ? 1 : 100;
emscripten_conditional_set_current_thread_status(
EM_THREAD_STATUS_RUNNING, EM_THREAD_STATUS_SLEEPING);
do {
// Keep processing the main loop of the calling thread.
__pthread_testcancel(); // pthreads spec: sleep is a cancellation point, so must test if this
// thread is cancelled during the sleep.
emscripten_current_thread_process_queued_calls();
now = emscripten_get_now();
double ms_to_sleep = target - now;
if (ms_to_sleep < min_ms_slice_to_sleep)
continue;
if (ms_to_sleep > max_ms_slice_to_sleep)
ms_to_sleep = max_ms_slice_to_sleep;
emscripten_futex_wait(&dummyZeroAddress, 0, ms_to_sleep);
now = emscripten_get_now();
} while (now < target);
emscripten_conditional_set_current_thread_status(
EM_THREAD_STATUS_SLEEPING, EM_THREAD_STATUS_RUNNING);
}
static struct pthread __main_pthread;
pthread_t emscripten_main_runtime_thread_id() {
return &__main_pthread;
}
void emscripten_current_thread_process_queued_calls() {
emscripten_proxy_execute_queue(emscripten_proxy_get_system_queue());
}
void emscripten_main_thread_process_queued_calls() {
assert(emscripten_is_main_runtime_thread());
emscripten_current_thread_process_queued_calls();
}
int _emscripten_thread_is_valid(pthread_t thread) {
return thread->self == thread;
}
static void *dummy_tsd[1] = { 0 };
weak_alias(dummy_tsd, __pthread_tsd_main);
// See system/lib/README.md for static constructor ordering.
__attribute__((constructor(48)))
void _emscripten_init_main_thread(void) {
_emscripten_init_main_thread_js(&__main_pthread);
// The pthread struct has a field that points to itself - this is used as
// a magic ID to detect whether the pthread_t structure is 'alive'.
__main_pthread.self = &__main_pthread;
__main_pthread.stack = (void*)emscripten_stack_get_base();
__main_pthread.stack_size = emscripten_stack_get_base() - emscripten_stack_get_end();
__main_pthread.detach_state = DT_JOINABLE;
// pthread struct robust_list head should point to itself.
__main_pthread.robust_list.head = &__main_pthread.robust_list.head;
// Main thread ID is always 1. It can't be 0 because musl assumes
// tid is always non-zero.
__main_pthread.tid = getpid();
__main_pthread.locale = &libc.global_locale;
// pthread struct prev and next should initially point to itself (see __init_tp),
// this is used by pthread_key_delete for deleting thread-specific data.
__main_pthread.next = __main_pthread.prev = &__main_pthread;
__main_pthread.tsd = (void **)__pthread_tsd_main;
_emscripten_thread_mailbox_init(&__main_pthread);
_emscripten_thread_mailbox_await(&__main_pthread);
}
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