Merge pull request #105 from lightpanda-io/cpu_profiler

expose CpuProfiler

Author: karlseguin

src/binding.cpp

@@ -3,6 +3,7 @@
 #include <cassert>
 #include "include/libplatform/libplatform.h"
 #include "include/v8-inspector.h"
+#include "include/v8-profiler.h"
 #include "include/v8.h"
 #include "src/api/api.h"
 #include "src/inspector/protocol/Runtime.h"
@@ -1728,6 +1729,61 @@ void v8__base__SetDcheckFunction(void (*func)(const char*, int, const char*)) {
     v8::base::SetDcheckFunction(func);
 }
 
+// CpuProfiler
+// -----------
+
+v8::CpuProfiler* v8__CpuProfiler__Get(v8::Isolate* isolate) {
+    return v8::CpuProfiler::New(isolate);
+}
+
+void v8__CpuProfiler__StartProfiling(v8::CpuProfiler* self, const v8::String& title) {
+    self->StartProfiling(ptr_to_local(&title), true);
+}
+
+const v8::CpuProfile* v8__CpuProfiler__StopProfiling(v8::CpuProfiler* self, const v8::String& title) {
+    return self->StopProfiling(ptr_to_local(&title));
+}
+
+void v8__CpuProfiler__UseDetailedSourcePositionsForProfiling(v8::Isolate* isolate) {
+    v8::CpuProfiler::UseDetailedSourcePositionsForProfiling(isolate);
+}
+
+void v8__CpuProfile__Delete(const v8::CpuProfile* self) {
+    const_cast<v8::CpuProfile*>(self)->Delete();
+}
+
+const v8::CpuProfileNode* v8__CpuProfile__GetTopDownRoot(const v8::CpuProfile* self) {
+    return self->GetTopDownRoot();
+}
+
+// Custom OutputStream that collects output into a string
+class StringOutputStream : public v8::OutputStream {
+public:
+    void EndOfStream() override {}
+
+    int GetChunkSize() override {
+        return 1024 * 1024; // 1MB chunks
+    }
+
+    v8::OutputStream::WriteResult WriteAsciiChunk(char* data, int size) override {
+        buffer_.append(data, size);
+        return v8::OutputStream::kContinue;
+    }
+
+    const std::string& str() const { return buffer_; }
+
+private:
+    std::string buffer_;
+};
+
+const v8::String* v8__CpuProfile__Serialize(const v8::CpuProfile* self, v8::Isolate* isolate) {
+    StringOutputStream stream;
+    self->Serialize(&stream);
+    return maybe_local_to_ptr(
+        v8::String::NewFromUtf8(isolate, stream.str().c_str(), v8::NewStringType::kNormal, stream.str().length())
+    );
+}
+
 // Inspector
 // ---------
 

src/binding.h

@@ -1097,6 +1097,21 @@ typedef struct {
     uint64_t len;
 } CZigString;
 
+// CpuProfiler
+// -----------
+
+typedef struct CpuProfiler CpuProfiler;
+typedef struct CpuProfile CpuProfile;
+typedef struct CpuProfileNode CpuProfileNode;
+
+CpuProfiler* v8__CpuProfiler__Get(Isolate* isolate);
+void v8__CpuProfiler__StartProfiling(CpuProfiler* self, const String* title);
+const CpuProfile* v8__CpuProfiler__StopProfiling(CpuProfiler* self, const String* title);
+void v8__CpuProfiler__UseDetailedSourcePositionsForProfiling(Isolate* isolate);
+void v8__CpuProfile__Delete(const CpuProfile* self);
+const CpuProfileNode* v8__CpuProfile__GetTopDownRoot(const CpuProfile* self);
+const String* v8__CpuProfile__Serialize(const CpuProfile* self, Isolate* isolate);
+
 // Inspector
 // ---------
 

src/v8.zig

@@ -3098,6 +3098,59 @@ pub const UnwrappedObject = struct {
     object_group: ?[]const u8,
 };
 
+pub const CpuProfiler = struct {
+    handle: *c.CpuProfiler,
+
+    pub fn init(isolate: Isolate) CpuProfiler {
+        return .{
+            .handle = c.v8__CpuProfiler__Get(isolate.handle).?,
+        };
+    }
+
+    pub fn startProfiling(self: CpuProfiler, title: String) void {
+        c.v8__CpuProfiler__StartProfiling(self.handle, title.handle);
+    }
+
+    pub fn stopProfiling(self: CpuProfiler, title: String) ?CpuProfile {
+        if (c.v8__CpuProfiler__StopProfiling(self.handle, title.handle)) |handle| {
+            return .{ .handle = handle };
+        }
+        return null;
+    }
+
+    pub fn useDetailedSourcePositionsForProfiling(isolate: Isolate) void {
+        c.v8__CpuProfiler__UseDetailedSourcePositionsForProfiling(isolate.handle);
+    }
+};
+
+pub const CpuProfile = struct {
+    handle: *const c.CpuProfile,
+
+    pub fn deinit(self: CpuProfile) void {
+        c.v8__CpuProfile__Delete(self.handle);
+    }
+
+    pub fn getTopDownRoot(self: CpuProfile) ?CpuProfileNode {
+        if (c.v8__CpuProfile__GetTopDownRoot(self.handle)) |handle| {
+            return .{ .handle = handle };
+        }
+        return null;
+    }
+
+    /// Serializes the profile to JSON format and returns it as a String.
+    pub fn serialize(self: CpuProfile, isolate: Isolate) ?String {
+        if (c.v8__CpuProfile__Serialize(self.handle, isolate.handle)) |handle| {
+            return String{ .handle = handle };
+        }
+        return null;
+    }
+};
+
+/// Represents a node in the CPU profile tree.
+pub const CpuProfileNode = struct {
+    handle: *const c.CpuProfileNode,
+};
+
 /// Note: Some getters return owned memory (strings), while others return memory owned by V8 (objects).
 /// The getters short-circuit if the default values is not available as converting the defaults to V8 causes unnecessary overhead.
 ///