base: add GetNumberOfThreads() to Linux and Android.

NOTRY=true

Review URL: https://chromiumcodereview.appspot.com/12193017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@180914 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 19 insertions, 0 deletions

diff --git a/base/process_util_unittest.cc b/base/process_util_unittest.cc
index 9897e41..309b87c 100644
--- a/base/process_util_unittest.cc
+++ b/base/process_util_unittest.cc
@@ -19,6 +19,7 @@
 #include "base/test/test_timeouts.h"
 #include "base/third_party/dynamic_annotations/dynamic_annotations.h"
 #include "base/threading/platform_thread.h"
+#include "base/threading/thread.h"
 #include "base/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/multiprocess_func_list.h"
@@ -944,6 +945,24 @@ TEST_F(ProcessUtilTest, ParseProcStatCPU) {
 
   EXPECT_EQ(0, base::ParseProcStatCPU(kSelfStat));
 }
+
+TEST_F(ProcessUtilTest, GetNumberOfThreads) {
+  const base::ProcessHandle current = base::GetCurrentProcessHandle();
+  const int initial_threads = base::GetNumberOfThreads(current);
+  ASSERT_GT(initial_threads, 0);
+  const int kNumAdditionalThreads = 10;
+  {
+    scoped_ptr<base::Thread> my_threads[kNumAdditionalThreads];
+    for (int i = 0; i < kNumAdditionalThreads; ++i) {
+      my_threads[i].reset(new base::Thread("GetNumberOfThreadsTest"));
+      my_threads[i]->Start();
+      ASSERT_EQ(base::GetNumberOfThreads(current), initial_threads + 1 + i);
+    }
+  }
+  // The Thread destructor will stop them.
+  ASSERT_EQ(initial_threads, base::GetNumberOfThreads(current));
+}
+
 #endif  // defined(OS_LINUX) || defined(OS_ANDROID)
 
 // TODO(port): port those unit tests.