Reland "Turn libbase into a component"

src/base/platform/mutex.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_BASE_PLATFORM_MUTEX_H_
 #define V8_BASE_PLATFORM_MUTEX_H_
 
+#include "src/base/base-export.h"
 #include "src/base/lazy-instance.h"
 #if V8_OS_WIN
 #include "src/base/win32-headers.h"
 #endif
 #include "src/base/logging.h"
 
 #if V8_OS_POSIX
 #include <pthread.h>  // NOLINT
 #endif
 
 namespace v8 {
 namespace base {
 
 // ----------------------------------------------------------------------------
 // Mutex
 //
 // This class is a synchronization primitive that can be used to protect shared
 // data from being simultaneously accessed by multiple threads. A mutex offers
 // exclusive, non-recursive ownership semantics:
 // - A calling thread owns a mutex from the time that it successfully calls
 //   either |Lock()| or |TryLock()| until it calls |Unlock()|.
 // - When a thread owns a mutex, all other threads will block (for calls to
 //   |Lock()|) or receive a |false| return value (for |TryLock()|) if they
 //   attempt to claim ownership of the mutex.
 // A calling thread must not own the mutex prior to calling |Lock()| or
 // |TryLock()|. The behavior of a program is undefined if a mutex is destroyed
 // while still owned by some thread. The Mutex class is non-copyable.
 
-class Mutex final {
+class V8_BASE_EXPORT Mutex final {
  public:
   Mutex();
   ~Mutex();
 
   // Locks the given mutex. If the mutex is currently unlocked, it becomes
   // locked and owned by the calling thread, and immediately. If the mutex
   // is already locked by another thread, suspends the calling thread until
   // the mutex is unlocked.
   void Lock();
 
@@ skipping 73 matching lines @@
 //   calls to |Unlock()|.
 // - When a thread owns a recursive mutex, all other threads will block (for
 //   calls to |Lock()|) or receive a |false| return value (for |TryLock()|) if
 //   they attempt to claim ownership of the recursive mutex.
 // - The maximum number of times that a recursive mutex may be locked is
 //   unspecified, but after that number is reached, calls to |Lock()| will
 //   probably abort the process and calls to |TryLock()| return false.
 // The behavior of a program is undefined if a recursive mutex is destroyed
 // while still owned by some thread. The RecursiveMutex class is non-copyable.
 
-class RecursiveMutex final {
+class V8_BASE_EXPORT RecursiveMutex final {
  public:
   RecursiveMutex();
   ~RecursiveMutex();
 
   // Locks the mutex. If another thread has already locked the mutex, a call to
   // |Lock()| will block execution until the lock is acquired. A thread may call
   // |Lock()| on a recursive mutex repeatedly. Ownership will only be released
   // after the thread makes a matching number of calls to |Unlock()|.
   // The behavior is undefined if the mutex is not unlocked before being
   // destroyed, i.e. some thread still owns it.
@@ skipping 66 matching lines @@
  private:
   Mutex* mutex_;
 
   DISALLOW_COPY_AND_ASSIGN(LockGuard);
 };
 
 }  // namespace base
 }  // namespace v8
 
 #endif  // V8_BASE_PLATFORM_MUTEX_H_