2 files changed, 123 insertions, 0 deletions
diff --git a/src/core/SkATrace.cpp b/src/core/SkATrace.cpp
new file mode 100644
index 0000000000..b40795e4da
--- /dev/null
+++ b/src/core/SkATrace.cpp
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkATrace.h"
+
+#include "SkTraceEvent.h"
+
+#ifdef SK_BUILD_FOR_ANDROID
+#include <dlfcn.h>
+#endif
+
+SkATrace::SkATrace() : fBeginSection(nullptr), fEndSection(nullptr), fIsEnabled(nullptr) {
+#ifdef SK_BUILD_FOR_ANDROID
+    if (void* lib = dlopen("libandroid.so", RTLD_NOW | RTLD_LOCAL)) {
+        fBeginSection = (decltype(fBeginSection))dlsym(lib, "ATrace_beginSection");
+        fEndSection = (decltype(fEndSection))dlsym(lib, "ATrace_endSection");
+        fIsEnabled = (decltype(fIsEnabled))dlsym(lib, "ATrace_isEnabled");
+    }
+#endif
+    if (!fIsEnabled) {
+        fIsEnabled = []{ return false; };
+    }
+}
+
+SkEventTracer::Handle SkATrace::addTraceEvent(char phase,
+                                              const uint8_t* categoryEnabledFlag,
+                                              const char* name,
+                                              uint64_t id,
+                                              int numArgs,
+                                              const char** argNames,
+                                              const uint8_t* argTypes,
+                                              const uint64_t* argValues,
+                                              uint8_t flags) {
+    if (fIsEnabled()) {
+        if (TRACE_EVENT_PHASE_COMPLETE == phase ||
+            TRACE_EVENT_PHASE_BEGIN == phase ||
+            TRACE_EVENT_PHASE_INSTANT == phase) {
+            fBeginSection(name);
+        }
+
+        if (TRACE_EVENT_PHASE_END == phase ||
+            TRACE_EVENT_PHASE_INSTANT == phase) {
+            fEndSection();
+        }
+    }
+    return 0;
+}
+
+void SkATrace::updateTraceEventDuration(const uint8_t* categoryEnabledFlag,
+                                        const char* name,
+                                        SkEventTracer::Handle handle) {
+    // This is only ever called from a scoped trace event so we will just end the ATrace section.
+    if (fIsEnabled()) {
+        fEndSection();
+    }
+}
+
+const uint8_t* SkATrace::getCategoryGroupEnabled(const char* name) {
+    // Chrome tracing is setup to not repeatly call this function once it has been initialized. So
+    // we can't use this to do a check for ATrace isEnabled(). Thus we will always return yes here
+    // and then check to see if ATrace is enabled when beginning and ending a section.
+    static uint8_t yes = SkEventTracer::kEnabledForRecording_CategoryGroupEnabledFlags;
+    return &yes;
+}
+
diff --git a/src/core/SkATrace.h b/src/core/SkATrace.h
new file mode 100644
index 0000000000..f870c5a57b
--- /dev/null
+++ b/src/core/SkATrace.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkATrace_DEFINED
+#define SkATrace_DEFINED
+
+#include "SkEventTracer.h"
+
+/**
+ * This class is used to support ATrace in android apps. It hooks into the SkEventTracer system. It
+ * currently supports the macros TRACE_EVENT*, TRACE_EVENT_INSTANT*, and TRANCE_EVENT_BEGIN/END*.
+ * For versions of these calls that take additoinal args and value pairs we currently just drop them
+ * and report only the name. Since ATrace is a simple push and pop system (all traces are fully
+ * nested), if using BEGIN and END you should also make sure your calls are properly nested (i.e. if
+ * startA is before startB, then endB is before endA).
+ */
+class SkATrace : public SkEventTracer {
+public:
+    SkATrace();
+
+    SkEventTracer::Handle addTraceEvent(char phase,
+                                        const uint8_t* categoryEnabledFlag,
+                                        const char* name,
+                                        uint64_t id,
+                                        int numArgs,
+                                        const char** argNames,
+                                        const uint8_t* argTypes,
+                                        const uint64_t* argValues,
+                                        uint8_t flags) override;
+
+
+    void updateTraceEventDuration(const uint8_t* categoryEnabledFlag,
+                                  const char* name,
+                                  SkEventTracer::Handle handle) override;
+
+    const uint8_t* getCategoryGroupEnabled(const char* name) override;
+
+    const char* getCategoryGroupName(const uint8_t* categoryEnabledFlag) override {
+        static const char* category = "skiaATrace";
+        return category;
+    }
+
+private:
+    void (*fBeginSection)(const char*);
+    void (*fEndSection)(void);
+    bool (*fIsEnabled)(void);
+};
+
+#endif
+