Bug 1166492 - Return UniquePtr<char[]> from profiler_get_profile to avoid double copying. (r=mstange)

dom/ipc/ContentChild.cpp

@@ -2655,10 +2655,9 @@ ContentChild::RecvStopProfiler()
 bool
 ContentChild::RecvGetProfile(nsCString* aProfile)
 {
-    char* profile = profiler_get_profile();
+    UniquePtr<char[]> profile = profiler_get_profile();
     if (profile) {
-        *aProfile = nsCString(profile, strlen(profile));
-        free(profile);
+        *aProfile = nsCString(profile.get(), strlen(profile.get()));
     } else {
         *aProfile = EmptyCString();
     }

dom/plugins/ipc/PluginModuleChild.cpp

@@ -2566,10 +2566,9 @@ PluginModuleChild::RecvStopProfiler()
 bool
 PluginModuleChild::AnswerGetProfile(nsCString* aProfile)
 {
-    char* profile = profiler_get_profile();
+    UniquePtr<char[]> profile = profiler_get_profile();
     if (profile != nullptr) {
-        *aProfile = nsCString(profile, strlen(profile));
-        free(profile);
+        *aProfile = nsCString(profile.get(), strlen(profile.get()));
     } else {
         *aProfile = nsCString("", 0);
     }

tools/profiler/GeckoProfiler.h

@@ -50,6 +50,7 @@
 #define SAMPLER_H
 
 #include "js/TypeDecls.h"
+#include "mozilla/UniquePtr.h"
 
 namespace mozilla {
 class TimeStamp;
@@ -159,7 +160,9 @@ static inline void profiler_responsiveness(const mozilla::TimeStamp& aTime) {}
 static inline void profiler_set_frame_number(int frameNumber) {}
 
 // Get the profile encoded as a JSON string.
-static inline char* profiler_get_profile(float aSinceTime = 0) { return nullptr; }
+static inline mozilla::UniquePtr<char[]> profiler_get_profile(float aSinceTime = 0) {
+  return nullptr;
+}
 
 // Get the profile encoded as a JSON object.
 static inline JSObject* profiler_get_profile_jsobject(JSContext* aCx,

tools/profiler/GeckoProfilerFunc.h

@@ -8,6 +8,7 @@
 
 #include "js/TypeDecls.h"
 #include "js/ProfilingStack.h"
+#include "mozilla/UniquePtr.h"
 #include <stdint.h>
 
 namespace mozilla {
@@ -53,7 +54,7 @@ const double* mozilla_sampler_get_responsiveness();
 
 void mozilla_sampler_save();
 
-char* mozilla_sampler_get_profile(float aSinceTime);
+mozilla::UniquePtr<char[]> mozilla_sampler_get_profile(float aSinceTime);
 
 JSObject *mozilla_sampler_get_profile_data(JSContext *aCx, float aSinceTime);
 

tools/profiler/GeckoProfilerImpl.h

@@ -144,7 +144,7 @@ void profiler_set_frame_number(int frameNumber)
 }
 
 static inline
-char* profiler_get_profile(float aSinceTime = 0)
+mozilla::UniquePtr<char[]> profiler_get_profile(float aSinceTime = 0)
 {
   return mozilla_sampler_get_profile(aSinceTime);
 }

tools/profiler/TableTicker.cpp

@@ -218,9 +218,7 @@ JSObject* TableTicker::ToJSObject(JSContext *aCx, float aSinceTime)
 {
   JS::RootedValue val(aCx);
   {
-    SpliceableChunkedJSONWriter b;
-    StreamJSON(b, aSinceTime);
-    UniquePtr<char[]> buf = b.WriteFunc()->CopyData();
+    UniquePtr<char[]> buf = ToJSON(aSinceTime);
     NS_ConvertUTF8toUTF16 js_string(nsDependentCString(buf.get()));
     MOZ_ALWAYS_TRUE(JS_ParseJSON(aCx, static_cast<const char16_t*>(js_string.get()),
                                  js_string.Length(), &val));
@@ -228,6 +226,13 @@ JSObject* TableTicker::ToJSObject(JSContext *aCx, float aSinceTime)
   return &val.toObject();
 }
 
+UniquePtr<char[]> TableTicker::ToJSON(float aSinceTime)
+{
+  SpliceableChunkedJSONWriter b;
+  StreamJSON(b, aSinceTime);
+  return b.WriteFunc()->CopyData();
+}
+
 struct SubprocessClosure {
   explicit SubprocessClosure(SpliceableJSONWriter *aWriter)
     : mWriter(aWriter)

tools/profiler/TableTicker.h

@@ -194,6 +194,7 @@ class TableTicker: public Sampler {
 
   void ToStreamAsJSON(std::ostream& stream, float aSinceTime = 0);
   virtual JSObject *ToJSObject(JSContext *aCx, float aSinceTime = 0);
+  mozilla::UniquePtr<char[]> ToJSON(float aSinceTime = 0);
   void StreamMetaJSCustomObject(SpliceableJSONWriter& aWriter);
   void StreamTaskTracer(SpliceableJSONWriter& aWriter);
   void FlushOnJSShutdown(JSRuntime* aRuntime);

tools/profiler/nsProfiler.cpp

@@ -119,14 +119,13 @@ nsProfiler::AddMarker(const char *aMarker)
 NS_IMETHODIMP
 nsProfiler::GetProfile(float aSinceTime, char **aProfile)
 {
-  char *profile = profiler_get_profile(aSinceTime);
+  mozilla::UniquePtr<char[]> profile = profiler_get_profile(aSinceTime);
   if (profile) {
-    size_t len = strlen(profile);
+    size_t len = strlen(profile.get());
     char *profileStr = static_cast<char *>
-                         (nsMemory::Clone(profile, (len + 1) * sizeof(char)));
+                         (nsMemory::Clone(profile.get(), (len + 1) * sizeof(char)));
     profileStr[len] = '\0';
     *aProfile = profileStr;
-    free(profile);
   }
   return NS_OK;
 }

tools/profiler/platform.cpp

@@ -561,17 +561,14 @@ void mozilla_sampler_save()
   t->HandleSaveRequest();
 }
 
-char* mozilla_sampler_get_profile(float aSinceTime)
+mozilla::UniquePtr<char[]> mozilla_sampler_get_profile(float aSinceTime)
 {
   TableTicker *t = tlsTicker.get();
   if (!t) {
     return nullptr;
   }
 
-  std::stringstream stream;
-  t->ToStreamAsJSON(stream, aSinceTime);
-  char* profile = strdup(stream.str().c_str());
-  return profile;
+  return t->ToJSON(aSinceTime);
 }
 
 JSObject *mozilla_sampler_get_profile_data(JSContext *aCx, float aSinceTime)

widget/android/AndroidJNI.cpp

@@ -1012,9 +1012,8 @@ Java_org_mozilla_gecko_ANRReporter_getNativeStack(JNIEnv* jenv, jclass)
     const PRIntervalTime timeout = PR_SecondsToInterval(5);
     const PRIntervalTime startTime = PR_IntervalNow();
 
-    typedef struct { void operator()(void* p) { free(p); } } ProfilePtrPolicy;
     // Pointer to a profile JSON string
-    typedef mozilla::UniquePtr<char, ProfilePtrPolicy> ProfilePtr;
+    typedef mozilla::UniquePtr<char[]> ProfilePtr;
 
     ProfilePtr profile(profiler_get_profile());