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-rw-r--r--third_party/abseil_cpp/absl/synchronization/internal/futex.h154
1 files changed, 0 insertions, 154 deletions
diff --git a/third_party/abseil_cpp/absl/synchronization/internal/futex.h b/third_party/abseil_cpp/absl/synchronization/internal/futex.h
deleted file mode 100644
index 06fbd6d072d1..000000000000
--- a/third_party/abseil_cpp/absl/synchronization/internal/futex.h
+++ /dev/null
@@ -1,154 +0,0 @@
-// Copyright 2020 The Abseil Authors.
-//
-// 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
-//
-//      https://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.
-#ifndef ABSL_SYNCHRONIZATION_INTERNAL_FUTEX_H_
-#define ABSL_SYNCHRONIZATION_INTERNAL_FUTEX_H_
-
-#include "absl/base/config.h"
-
-#ifdef _WIN32
-#include <windows.h>
-#else
-#include <sys/time.h>
-#include <unistd.h>
-#endif
-
-#ifdef __linux__
-#include <linux/futex.h>
-#include <sys/syscall.h>
-#endif
-
-#include <errno.h>
-#include <stdio.h>
-#include <time.h>
-
-#include <atomic>
-#include <cstdint>
-
-#include "absl/base/optimization.h"
-#include "absl/synchronization/internal/kernel_timeout.h"
-
-#ifdef ABSL_INTERNAL_HAVE_FUTEX
-#error ABSL_INTERNAL_HAVE_FUTEX may not be set on the command line
-#elif defined(__BIONIC__)
-// Bionic supports all the futex operations we need even when some of the futex
-// definitions are missing.
-#define ABSL_INTERNAL_HAVE_FUTEX
-#elif defined(__linux__) && defined(FUTEX_CLOCK_REALTIME)
-// FUTEX_CLOCK_REALTIME requires Linux >= 2.6.28.
-#define ABSL_INTERNAL_HAVE_FUTEX
-#endif
-
-#ifdef ABSL_INTERNAL_HAVE_FUTEX
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace synchronization_internal {
-
-// Some Android headers are missing these definitions even though they
-// support these futex operations.
-#ifdef __BIONIC__
-#ifndef SYS_futex
-#define SYS_futex __NR_futex
-#endif
-#ifndef FUTEX_WAIT_BITSET
-#define FUTEX_WAIT_BITSET 9
-#endif
-#ifndef FUTEX_PRIVATE_FLAG
-#define FUTEX_PRIVATE_FLAG 128
-#endif
-#ifndef FUTEX_CLOCK_REALTIME
-#define FUTEX_CLOCK_REALTIME 256
-#endif
-#ifndef FUTEX_BITSET_MATCH_ANY
-#define FUTEX_BITSET_MATCH_ANY 0xFFFFFFFF
-#endif
-#endif
-
-#if defined(__NR_futex_time64) && !defined(SYS_futex_time64)
-#define SYS_futex_time64 __NR_futex_time64
-#endif
-
-#if defined(SYS_futex_time64) && !defined(SYS_futex)
-#define SYS_futex SYS_futex_time64
-#endif
-
-class FutexImpl {
- public:
-  static int WaitUntil(std::atomic<int32_t> *v, int32_t val,
-                       KernelTimeout t) {
-    int err = 0;
-    if (t.has_timeout()) {
-      // https://locklessinc.com/articles/futex_cheat_sheet/
-      // Unlike FUTEX_WAIT, FUTEX_WAIT_BITSET uses absolute time.
-      struct timespec abs_timeout = t.MakeAbsTimespec();
-      // Atomically check that the futex value is still 0, and if it
-      // is, sleep until abs_timeout or until woken by FUTEX_WAKE.
-      err = syscall(
-          SYS_futex, reinterpret_cast<int32_t *>(v),
-          FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME, val,
-          &abs_timeout, nullptr, FUTEX_BITSET_MATCH_ANY);
-    } else {
-      // Atomically check that the futex value is still 0, and if it
-      // is, sleep until woken by FUTEX_WAKE.
-      err = syscall(SYS_futex, reinterpret_cast<int32_t *>(v),
-                    FUTEX_WAIT | FUTEX_PRIVATE_FLAG, val, nullptr);
-    }
-    if (ABSL_PREDICT_FALSE(err != 0)) {
-      err = -errno;
-    }
-    return err;
-  }
-
-  static int WaitBitsetAbsoluteTimeout(std::atomic<int32_t> *v, int32_t val,
-                                       int32_t bits,
-                                       const struct timespec *abstime) {
-    int err = syscall(SYS_futex, reinterpret_cast<int32_t *>(v),
-                      FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG, val, abstime,
-                      nullptr, bits);
-    if (ABSL_PREDICT_FALSE(err != 0)) {
-      err = -errno;
-    }
-    return err;
-  }
-
-  static int Wake(std::atomic<int32_t> *v, int32_t count) {
-    int err = syscall(SYS_futex, reinterpret_cast<int32_t *>(v),
-                      FUTEX_WAKE | FUTEX_PRIVATE_FLAG, count);
-    if (ABSL_PREDICT_FALSE(err < 0)) {
-      err = -errno;
-    }
-    return err;
-  }
-
-  // FUTEX_WAKE_BITSET
-  static int WakeBitset(std::atomic<int32_t> *v, int32_t count, int32_t bits) {
-    int err = syscall(SYS_futex, reinterpret_cast<int32_t *>(v),
-                      FUTEX_WAKE_BITSET | FUTEX_PRIVATE_FLAG, count, nullptr,
-                      nullptr, bits);
-    if (ABSL_PREDICT_FALSE(err < 0)) {
-      err = -errno;
-    }
-    return err;
-  }
-};
-
-class Futex : public FutexImpl {};
-
-}  // namespace synchronization_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_INTERNAL_HAVE_FUTEX
-
-#endif  // ABSL_SYNCHRONIZATION_INTERNAL_FUTEX_H_