cosmopolitan/third_party/nsync/mu_semaphore.c
Justine Tunney bcf9af94bf
Get threads working well on MacOS Arm64
- Now using 10x better GCD semaphores
- We now generate Linux-like thread ids
- We now use fast system clock / sleep libraries
- The APE M1 loader now generates Linux-like stacks
2023-06-04 01:57:10 -07:00

72 lines
3.3 KiB
C

/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
│vi: set et ft=c ts=8 tw=8 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2016 Google Inc. │
│ │
│ Licensed under the Apache License, Version 2.0 (the "License"); │
│ you may not use this file except in compliance with the License. │
│ You may obtain a copy of the License at │
│ │
│ http://www.apache.org/licenses/LICENSE-2.0 │
│ │
│ Unless required by applicable law or agreed to in writing, software │
│ distributed under the License is distributed on an "AS IS" BASIS, │
│ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. │
│ See the License for the specific language governing permissions and │
│ limitations under the License. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "third_party/nsync/mu_semaphore.h"
#include "libc/dce.h"
#include "third_party/nsync/mu_semaphore.internal.h"
asm(".ident\t\"\\n\\n\
*NSYNC (Apache 2.0)\\n\
Copyright 2016 Google, Inc.\\n\
https://github.com/google/nsync\"");
// clang-format off
/* Initialize *s; the initial value is 0. */
void nsync_mu_semaphore_init (nsync_semaphore *s) {
if (IsXnuSilicon ()) {
return nsync_mu_semaphore_init_gcd (s);
} else if (IsNetbsd ()) {
return nsync_mu_semaphore_init_sem (s);
} else {
return nsync_mu_semaphore_init_futex (s);
}
}
/* Wait until the count of *s exceeds 0, and decrement it. */
errno_t nsync_mu_semaphore_p (nsync_semaphore *s) {
if (IsXnuSilicon ()) {
return nsync_mu_semaphore_p_gcd (s);
} else if (IsNetbsd ()) {
return nsync_mu_semaphore_p_sem (s);
} else {
return nsync_mu_semaphore_p_futex (s);
}
}
/* Wait until one of:
the count of *s is non-zero, in which case decrement *s and return 0;
or abs_deadline expires, in which case return ETIMEDOUT. */
errno_t nsync_mu_semaphore_p_with_deadline (nsync_semaphore *s, nsync_time abs_deadline) {
if (IsXnuSilicon ()) {
return nsync_mu_semaphore_p_with_deadline_gcd (s, abs_deadline);
} else if (IsNetbsd ()) {
return nsync_mu_semaphore_p_with_deadline_sem (s, abs_deadline);
} else {
return nsync_mu_semaphore_p_with_deadline_futex (s, abs_deadline);
}
}
/* Ensure that the count of *s is at least 1. */
void nsync_mu_semaphore_v (nsync_semaphore *s) {
if (IsXnuSilicon ()) {
return nsync_mu_semaphore_v_gcd (s);
} else if (IsNetbsd ()) {
return nsync_mu_semaphore_v_sem (s);
} else {
return nsync_mu_semaphore_v_futex (s);
}
}