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-rw-r--r--third_party/abseil_cpp/absl/base/internal/thread_identity.cc155
1 files changed, 0 insertions, 155 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/thread_identity.cc b/third_party/abseil_cpp/absl/base/internal/thread_identity.cc
deleted file mode 100644
index 6ea010ed0d31..000000000000
--- a/third_party/abseil_cpp/absl/base/internal/thread_identity.cc
+++ /dev/null
@@ -1,155 +0,0 @@
-// 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.
-
-#include "absl/base/internal/thread_identity.h"
-
-#ifndef _WIN32
-#include <pthread.h>
-#include <signal.h>
-#endif
-
-#include <atomic>
-#include <cassert>
-#include <memory>
-
-#include "absl/base/attributes.h"
-#include "absl/base/call_once.h"
-#include "absl/base/internal/raw_logging.h"
-#include "absl/base/internal/spinlock.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace base_internal {
-
-#if ABSL_THREAD_IDENTITY_MODE != ABSL_THREAD_IDENTITY_MODE_USE_CPP11
-namespace {
-// Used to co-ordinate one-time creation of our pthread_key
-absl::once_flag init_thread_identity_key_once;
-pthread_key_t thread_identity_pthread_key;
-std::atomic<bool> pthread_key_initialized(false);
-
-void AllocateThreadIdentityKey(ThreadIdentityReclaimerFunction reclaimer) {
-  pthread_key_create(&thread_identity_pthread_key, reclaimer);
-  pthread_key_initialized.store(true, std::memory_order_release);
-}
-}  // namespace
-#endif
-
-#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \
-    ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
-// The actual TLS storage for a thread's currently associated ThreadIdentity.
-// This is referenced by inline accessors in the header.
-// "protected" visibility ensures that if multiple instances of Abseil code
-// exist within a process (via dlopen() or similar), references to
-// thread_identity_ptr from each instance of the code will refer to
-// *different* instances of this ptr.
-// Apple platforms have the visibility attribute, but issue a compile warning
-// that protected visibility is unsupported.
-#if ABSL_HAVE_ATTRIBUTE(visibility) && !defined(__APPLE__)
-__attribute__((visibility("protected")))
-#endif  // ABSL_HAVE_ATTRIBUTE(visibility) && !defined(__APPLE__)
-#if ABSL_PER_THREAD_TLS
-// Prefer __thread to thread_local as benchmarks indicate it is a bit faster.
-ABSL_PER_THREAD_TLS_KEYWORD ThreadIdentity* thread_identity_ptr = nullptr;
-#elif defined(ABSL_HAVE_THREAD_LOCAL)
-thread_local ThreadIdentity* thread_identity_ptr = nullptr;
-#endif  // ABSL_PER_THREAD_TLS
-#endif  // TLS or CPP11
-
-void SetCurrentThreadIdentity(
-    ThreadIdentity* identity, ThreadIdentityReclaimerFunction reclaimer) {
-  assert(CurrentThreadIdentityIfPresent() == nullptr);
-  // Associate our destructor.
-  // NOTE: This call to pthread_setspecific is currently the only immovable
-  // barrier to CurrentThreadIdentity() always being async signal safe.
-#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
-  // NOTE: Not async-safe.  But can be open-coded.
-  absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,
-                  reclaimer);
-
-#if defined(__EMSCRIPTEN__) || defined(__MINGW32__)
-  // Emscripten and MinGW pthread implementations does not support signals.
-  // See https://kripken.github.io/emscripten-site/docs/porting/pthreads.html
-  // for more information.
-  pthread_setspecific(thread_identity_pthread_key,
-                      reinterpret_cast<void*>(identity));
-#else
-  // We must mask signals around the call to setspecific as with current glibc,
-  // a concurrent getspecific (needed for GetCurrentThreadIdentityIfPresent())
-  // may zero our value.
-  //
-  // While not officially async-signal safe, getspecific within a signal handler
-  // is otherwise OK.
-  sigset_t all_signals;
-  sigset_t curr_signals;
-  sigfillset(&all_signals);
-  pthread_sigmask(SIG_SETMASK, &all_signals, &curr_signals);
-  pthread_setspecific(thread_identity_pthread_key,
-                      reinterpret_cast<void*>(identity));
-  pthread_sigmask(SIG_SETMASK, &curr_signals, nullptr);
-#endif  // !__EMSCRIPTEN__ && !__MINGW32__
-
-#elif ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS
-  // NOTE: Not async-safe.  But can be open-coded.
-  absl::call_once(init_thread_identity_key_once, AllocateThreadIdentityKey,
-                  reclaimer);
-  pthread_setspecific(thread_identity_pthread_key,
-                      reinterpret_cast<void*>(identity));
-  thread_identity_ptr = identity;
-#elif ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
-  thread_local std::unique_ptr<ThreadIdentity, ThreadIdentityReclaimerFunction>
-      holder(identity, reclaimer);
-  thread_identity_ptr = identity;
-#else
-#error Unimplemented ABSL_THREAD_IDENTITY_MODE
-#endif
-}
-
-#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \
-    ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
-
-// Please see the comment on `CurrentThreadIdentityIfPresent` in
-// thread_identity.h. Because DLLs cannot expose thread_local variables in
-// headers, we opt for the correct-but-slower option of placing the definition
-// of this function only in a translation unit inside DLL.
-#if defined(ABSL_BUILD_DLL) || defined(ABSL_CONSUME_DLL)
-ThreadIdentity* CurrentThreadIdentityIfPresent() { return thread_identity_ptr; }
-#endif
-#endif
-
-void ClearCurrentThreadIdentity() {
-#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_TLS || \
-    ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_CPP11
-  thread_identity_ptr = nullptr;
-#elif ABSL_THREAD_IDENTITY_MODE == \
-      ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
-  // pthread_setspecific expected to clear value on destruction
-  assert(CurrentThreadIdentityIfPresent() == nullptr);
-#endif
-}
-
-#if ABSL_THREAD_IDENTITY_MODE == ABSL_THREAD_IDENTITY_MODE_USE_POSIX_SETSPECIFIC
-ThreadIdentity* CurrentThreadIdentityIfPresent() {
-  bool initialized = pthread_key_initialized.load(std::memory_order_acquire);
-  if (!initialized) {
-    return nullptr;
-  }
-  return reinterpret_cast<ThreadIdentity*>(
-      pthread_getspecific(thread_identity_pthread_key));
-}
-#endif
-
-}  // namespace base_internal
-ABSL_NAMESPACE_END
-}  // namespace absl