More PNaCL fixes (without GYP/Makefile tweaks)

src/base/platform/semaphore.cc

 // 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.
 
 #include "src/base/platform/semaphore.h"
 
 #if V8_OS_MACOSX
 #include <mach/mach_init.h>
 #include <mach/task.h>
 #endif
 
 #include <errno.h>
 
 #include "src/base/logging.h"
+#include "src/base/platform/elapsed-timer.h"
 #include "src/base/platform/time.h"
 
 namespace v8 {
 namespace base {
 
 #if V8_OS_MACOSX
 
 Semaphore::Semaphore(int count) {
   kern_return_t result = semaphore_create(
       mach_task_self(), &native_handle_, SYNC_POLICY_FIFO, count);
@@ skipping 74 matching lines @@
     int result = sem_wait(&native_handle_);
     if (result == 0) return;  // Semaphore was signalled.
     // Signal caused spurious wakeup.
     DCHECK_EQ(-1, result);
     DCHECK_EQ(EINTR, errno);
   }
 }
 
 
 bool Semaphore::WaitFor(const TimeDelta& rel_time) {
+#if V8_OS_NACL
+  // PNaCL doesn't support sem_timedwait, do ugly busy waiting.
+  ElapsedTimer timer;
+  timer.Start();
+  do {
+    int result = sem_trywait(&native_handle_);
+    if (result == 0) return true;
+    DCHECK(errno == EAGAIN || error == EINTR);
+  } while (!timer.HasExpired(rel_time));
+  return false;
+#else
   // Compute the time for end of timeout.
   const Time time = Time::NowFromSystemTime() + rel_time;
   const struct timespec ts = time.ToTimespec();
 
   // Wait for semaphore signalled or timeout.
   while (true) {
     int result = sem_timedwait(&native_handle_, &ts);
     if (result == 0) return true;  // Semaphore was signalled.
 #if V8_LIBC_GLIBC && !V8_GLIBC_PREREQ(2, 4)
     if (result > 0) {
       // sem_timedwait in glibc prior to 2.3.4 returns the errno instead of -1.
       errno = result;
       result = -1;
     }
 #endif
     if (result == -1 && errno == ETIMEDOUT) {
       // Timed out while waiting for semaphore.
       return false;
     }
     // Signal caused spurious wakeup.
     DCHECK_EQ(-1, result);
     DCHECK_EQ(EINTR, errno);
   }
+#endif
 }
 
 #elif V8_OS_WIN
 
 Semaphore::Semaphore(int count) {
   DCHECK(count >= 0);
   native_handle_ = ::CreateSemaphoreA(NULL, count, 0x7fffffff, NULL);
   DCHECK(native_handle_ != NULL);
 }
 
@@ skipping 40 matching lines @@
       }
       DCHECK(result == WAIT_OBJECT_0);
       return true;
     }
   }
 }
 
 #endif  // V8_OS_MACOSX
 
 } }  // namespace v8::base