add missing include to ThreadId.h

Summary:
The syscall() function is defined in <unistd.h>
<sys/syscall.h> apparently only defines IDs to be used with syscall(), but does
not define the syscall() function itself.

This caused build failures for files that included ThreadId.h before unistd.h

Reviewed By: Orvid

Differential Revision: D5189658

fbshipit-source-id: 2ec8ea1d58f3fc14cf458a53ecaa811978527398

CMakeLists.txt

@@ -530,6 +530,7 @@ if (BUILD_TESTS)
       TEST synchronized_test SOURCES SynchronizedTest.cpp
       TEST thread_cached_arena_test SOURCES ThreadCachedArenaTest.cpp
       TEST thread_cached_int_test SOURCES ThreadCachedIntTest.cpp
+      TEST thread_id_test SOURCES ThreadIdTest.cpp
       TEST thread_local_test SOURCES ThreadLocalTest.cpp
       TEST thread_name_test SOURCES ThreadNameTest.cpp
       TEST timeout_queue_test SOURCES TimeoutQueueTest.cpp

folly/ThreadId.h

@@ -20,6 +20,7 @@
 
 #include <folly/portability/PThread.h>
 #include <folly/portability/SysSyscall.h>
+#include <folly/portability/Unistd.h>
 #include <folly/portability/Windows.h>
 
 namespace folly {

folly/test/Makefile.am

@@ -96,6 +96,9 @@ TESTS += fbstring_test_using_jemalloc
 thread_cached_int_test_SOURCES = ThreadCachedIntTest.cpp
 thread_cached_int_test_LDADD = libfollytestmain.la $(top_builddir)/libfollybenchmark.la
 
+thread_id_test_SOURCES = ThreadIdTest.cpp
+thread_id_test_LDADD = libfollytestmain.la
+
 thread_local_test_SOURCES = ThreadLocalTest.cpp
 thread_local_test_LDADD = libfollytestmain.la $(top_builddir)/libfollybenchmark.la
 thread_local_test_LDFLAGS = -ldl

folly/test/ThreadIdTest.cpp

+/*
+ * Copyright 2017 Facebook, Inc.
+ *
+ * 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
+ *
+ *   http://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.
+ */
+
+// Make sure we include ThreadId.h before anything else.
+// There is no ThreadId.cpp file, so this test is the only thing that verifies
+// that ThreadId.h compiles by itself when included first.
+#include <folly/ThreadId.h>
+
+#include <thread>
+
+#include <folly/portability/GTest.h>
+
+TEST(ThreadId, getCurrentID) {
+  auto thisThreadID = folly::getCurrentThreadID();
+  uint64_t otherThreadID;
+  std::thread otherThread{[&] { otherThreadID = folly::getCurrentThreadID(); }};
+  otherThread.join();
+  EXPECT_NE(thisThreadID, otherThreadID);
+}
+
+TEST(ThreadId, getOSThreadID) {
+  auto thisThreadID = folly::getOSThreadID();
+  uint64_t otherThreadID;
+  std::thread otherThread{[&] { otherThreadID = folly::getOSThreadID(); }};
+  otherThread.join();
+  EXPECT_NE(thisThreadID, otherThreadID);
+}