[Isolates] Merge from bleeding_edge to isolates, revisions 6100-6300.

src/platform-macos.cc

Index: src/platform-macos.cc
===================================================================
--- src/platform-macos.cc	(revision 6941)
+++ src/platform-macos.cc	(working copy)
@@ -28,6 +28,7 @@
 // Platform specific code for MacOS goes here. For the POSIX comaptible parts
 // the implementation is in platform-posix.cc.
 
+#include <dlfcn.h>
 #include <unistd.h>
 #include <sys/mman.h>
 #include <mach/mach_init.h>
@@ -49,7 +50,6 @@
 #include <sys/types.h>
 #include <stdarg.h>
 #include <stdlib.h>
-
 #include <errno.h>
 
 #undef MAP_TYPE
@@ -420,19 +420,46 @@
 Thread::Thread(Isolate* isolate)
     : ThreadHandle(ThreadHandle::INVALID),
       isolate_(isolate) {
+  set_name("v8:<unknown>");
 }
 
 
+Thread::Thread(Isolate* isolate, const char* name)
+    : ThreadHandle(ThreadHandle::INVALID),
+      isolate_(isolate) {
+  set_name(name);
+}
+
+
 Thread::~Thread() {
 }
 
 
+
+static void SetThreadName(const char* name) {
+  // pthread_setname_np is only available in 10.6 or later, so test
+  // for it at runtime.
+  int (*dynamic_pthread_setname_np)(const char*);
+  *reinterpret_cast<void**>(&dynamic_pthread_setname_np) =
+    dlsym(RTLD_DEFAULT, "pthread_setname_np");
+  if (!dynamic_pthread_setname_np)
+    return;
+
+  // Mac OS X does not expose the length limit of the name, so hardcode it.
+  static const int kMaxNameLength = 63;
+  USE(kMaxNameLength);
+  ASSERT(Thread::kMaxThreadNameLength <= kMaxNameLength);
+  dynamic_pthread_setname_np(name);
+}
+
+
 static void* ThreadEntry(void* arg) {
   Thread* thread = reinterpret_cast<Thread*>(arg);
   // This is also initialized by the first argument to pthread_create() but we
   // don't know which thread will run first (the original thread or the new
   // one) so we initialize it here too.
   thread->thread_handle_data()->thread_ = pthread_self();
+  SetThreadName(thread->name());
   ASSERT(thread->IsValid());
   Thread::SetThreadLocal(Isolate::isolate_key(), thread->isolate());
   thread->Run();
@@ -440,6 +467,12 @@
 }
 
 
+void Thread::set_name(const char* name) {
+  strncpy(name_, name, sizeof(name_));
+  name_[sizeof(name_) - 1] = '\0';
+}
+
+
 void Thread::Start() {
   pthread_create(&thread_handle_data()->thread_, NULL, ThreadEntry, this);
 }