mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 11:37:35 +00:00
2fc507c98f
* modelines: tw -> sw shiftwidth, not textwidth. * space-surround modelines * fix irregular modelines * Fix modeline in titlegen.c
89 lines
4.2 KiB
C
89 lines
4.2 KiB
C
/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8 -*-│
|
|
│ vi: set noet ft=c ts=8 sw=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/calls/cp.internal.h"
|
|
#include "libc/dce.h"
|
|
#include "third_party/nsync/mu_semaphore.internal.h"
|
|
|
|
/* Apple's ulock (part by Cosmo futexes) is an internal API, but:
|
|
1. Unlike GCD it's cancellable, i.e. can be EINTR'd by signals
|
|
2. We currently always use ulock anyway for joining threads */
|
|
#define PREFER_GCD_OVER_ULOCK 1
|
|
|
|
asm(".ident\t\"\\n\\n\
|
|
*NSYNC (Apache 2.0)\\n\
|
|
Copyright 2016 Google, Inc.\\n\
|
|
https://github.com/google/nsync\"");
|
|
|
|
/* Initialize *s; the initial value is 0. */
|
|
void nsync_mu_semaphore_init (nsync_semaphore *s) {
|
|
if (PREFER_GCD_OVER_ULOCK && 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. If POSIX cancellations
|
|
are currently disabled by the thread, then this function always succeeds. When
|
|
they're enabled in MASKED mode, this function may return ECANCELED. Otherwise,
|
|
cancellation will occur by unwinding cleanup handlers pushed to the stack. */
|
|
errno_t nsync_mu_semaphore_p (nsync_semaphore *s) {
|
|
errno_t err;
|
|
BEGIN_CANCELATION_POINT;
|
|
if (PREFER_GCD_OVER_ULOCK && IsXnuSilicon ()) {
|
|
err = nsync_mu_semaphore_p_gcd (s);
|
|
} else if (IsNetbsd ()) {
|
|
err = nsync_mu_semaphore_p_sem (s);
|
|
} else {
|
|
err = nsync_mu_semaphore_p_futex (s);
|
|
}
|
|
END_CANCELATION_POINT;
|
|
return err;
|
|
}
|
|
|
|
/* Like nsync_mu_semaphore_p() this waits for the count of *s to exceed 0,
|
|
while additionally supporting a time parameter specifying at what point
|
|
in the future ETIMEDOUT should be returned, if neither cancelation, or
|
|
semaphore release happens. */
|
|
errno_t nsync_mu_semaphore_p_with_deadline (nsync_semaphore *s, nsync_time abs_deadline) {
|
|
errno_t err;
|
|
BEGIN_CANCELATION_POINT;
|
|
if (PREFER_GCD_OVER_ULOCK && IsXnuSilicon ()) {
|
|
err = nsync_mu_semaphore_p_with_deadline_gcd (s, abs_deadline);
|
|
} else if (IsNetbsd ()) {
|
|
err = nsync_mu_semaphore_p_with_deadline_sem (s, abs_deadline);
|
|
} else {
|
|
err = nsync_mu_semaphore_p_with_deadline_futex (s, abs_deadline);
|
|
}
|
|
END_CANCELATION_POINT;
|
|
return err;
|
|
}
|
|
|
|
/* Ensure that the count of *s is at least 1. */
|
|
void nsync_mu_semaphore_v (nsync_semaphore *s) {
|
|
if (PREFER_GCD_OVER_ULOCK && 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);
|
|
}
|
|
}
|