SkOncePtr

New abstraction to replace all of: SkOnce, SkLazyPtr, SkLazyFnPtr.

BUG=skia:

Review URL: https://codereview.chromium.org/1301323006

1 files changed, 50 insertions, 0 deletions

diff --git a/tests/OncePtrTest.cpp b/tests/OncePtrTest.cpp
new file mode 100644
index 0000000000..1b348dfd2d
--- /dev/null
+++ b/tests/OncePtrTest.cpp
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Test.h"
+#include "SkOncePtr.h"
+#include "SkTaskGroup.h"
+
+DEF_TEST(OncePtr, r) {
+    SkOncePtr<int> once;
+
+    static SkAtomic<int> calls(0);
+    auto create = [&] {
+        calls.fetch_add(1);
+        return new int(5);
+    };
+
+    SkAtomic<int> force_a_race(sk_num_cores());
+
+    sk_parallel_for(sk_num_cores()*4, [&](size_t) {
+        force_a_race.fetch_add(-1);
+        while (force_a_race.load() > 0);
+
+        int* n = once.get(create);
+        REPORTER_ASSERT(r, *n == 5);
+    });
+    REPORTER_ASSERT(r, calls.load() == 1);
+
+    delete (int*)once;
+}
+
+/* TODO(mtklein): next CL
+
+SK_DECLARE_STATIC_ONCE(once_noptr);
+DEF_TEST(OnceNoPtr, r) {
+    static SkAtomic<int> calls(0);
+
+    SkAtomic<int> force_a_race(sk_num_cores());
+    sk_parallel_for(sk_num_cores()*4, [&](size_t) {
+        force_a_race.fetch_add(-1);
+        while (force_a_race.load() > 0);
+
+        SkOnce(&once_noptr, [&] { calls.fetch_add(1); });
+    });
+    REPORTER_ASSERT(r, calls.load() == 1);
+}
+*/