1 files changed, 39 insertions, 2 deletions
diff --git a/tools/trace/SkEventTracingPriv.cpp b/tools/trace/SkEventTracingPriv.cpp
index 217511ffa7..c4c793b06e 100644
--- a/tools/trace/SkEventTracingPriv.cpp
+++ b/tools/trace/SkEventTracingPriv.cpp
@@ -8,10 +8,11 @@
 #include "SkEventTracingPriv.h"
 
 #include "SkATrace.h"
-#include "SkCommandLineFlags.h"
-#include "SkEventTracer.h"
 #include "SkChromeTracingTracer.h"
+#include "SkCommandLineFlags.h"
 #include "SkDebugfTracer.h"
+#include "SkEventTracer.h"
+#include "SkTraceEventCommon.h"
 
 DEFINE_string(trace, "",
               "Log trace events in one of several modes:\n"
@@ -42,3 +43,39 @@ void initializeEventTracingForTools(int32_t* threadsFlag) {
 
     SkAssertResult(SkEventTracer::SetInstance(eventTracer));
 }
+
+uint8_t* SkEventTracingCategories::getCategoryGroupEnabled(const char* name) {
+    static_assert(0 == offsetof(CategoryState, fEnabled), "CategoryState");
+
+    // We ignore the "disabled-by-default-" prefix in our internal tools (though we could honor it)
+    if (SkStrStartsWith(name, TRACE_DISABLED_BY_DEFAULT_PREFIX)) {
+        name += strlen(TRACE_DISABLED_BY_DEFAULT_PREFIX);
+    }
+
+    // Chrome's implementation of this API does a two-phase lookup (once without a lock, then again
+    // with a lock. But the tracing macros avoid calling these functions more than once per site,
+    // so just do something simple (and easier to reason about):
+    SkAutoMutexAcquire lock(&fMutex);
+    for (int i = 0; i < fNumCategories; ++i) {
+        if (0 == strcmp(name, fCategories[i].fName)) {
+            return reinterpret_cast<uint8_t*>(&fCategories[i]);
+        }
+    }
+
+    if (fNumCategories >= kMaxCategories) {
+        SkDEBUGFAIL("Exhausted event tracing categories. Increase kMaxCategories.");
+        return reinterpret_cast<uint8_t*>(&fCategories[0]);
+    }
+
+    fCategories[fNumCategories].fEnabled =
+            SkEventTracer::kEnabledForRecording_CategoryGroupEnabledFlags;
+    fCategories[fNumCategories].fName = name;
+    return reinterpret_cast<uint8_t*>(&fCategories[fNumCategories++]);
+}
+
+const char* SkEventTracingCategories::getCategoryGroupName(const uint8_t* categoryEnabledFlag) {
+    if (categoryEnabledFlag) {
+        return reinterpret_cast<const CategoryState*>(categoryEnabledFlag)->fName;
+    }
+    return nullptr;
+}