Add 'third_party/abseil_cpp/' from commit '768eb2ca2857342673fcd462792ce04b8bac3fa3' r/781

git-subtree-dir: third_party/abseil_cpp
git-subtree-mainline: ffb2ae54beb5796cd408fbe15d2d2da09ff37adf
git-subtree-split: 768eb2ca2857342673fcd462792ce04b8bac3fa3

1 files changed, 46 insertions, 0 deletions

diff --git a/third_party/abseil_cpp/absl/base/internal/spinlock_posix.inc b/third_party/abseil_cpp/absl/base/internal/spinlock_posix.inc
new file mode 100644
index 000000000000..fcd21b151b6e
--- /dev/null
+++ b/third_party/abseil_cpp/absl/base/internal/spinlock_posix.inc
@@ -0,0 +1,46 @@
+// Copyright 2017 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.
+//
+// This file is a Posix-specific part of spinlock_wait.cc
+
+#include <sched.h>
+
+#include <atomic>
+#include <ctime>
+
+#include "absl/base/internal/errno_saver.h"
+#include "absl/base/internal/scheduling_mode.h"
+#include "absl/base/port.h"
+
+extern "C" {
+
+ABSL_ATTRIBUTE_WEAK void AbslInternalSpinLockDelay(
+    std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */, int loop,
+    absl::base_internal::SchedulingMode /* mode */) {
+  absl::base_internal::ErrnoSaver errno_saver;
+  if (loop == 0) {
+  } else if (loop == 1) {
+    sched_yield();
+  } else {
+    struct timespec tm;
+    tm.tv_sec = 0;
+    tm.tv_nsec = absl::base_internal::SpinLockSuggestedDelayNS(loop);
+    nanosleep(&tm, nullptr);
+  }
+}
+
+ABSL_ATTRIBUTE_WEAK void AbslInternalSpinLockWake(
+    std::atomic<uint32_t>* /* lock_word */, bool /* all */) {}
+
+}  // extern "C"