1 #include <node.h>
2 #include <node_buffer.h>
3 #include <zlib.h>
4 #include <assert.h>
5
6 namespace {
7
CompressBytes(const v8::FunctionCallbackInfo<v8::Value> & info)8 inline void CompressBytes(const v8::FunctionCallbackInfo<v8::Value>& info) {
9 assert(info[0]->IsArrayBufferView());
10 auto view = info[0].As<v8::ArrayBufferView>();
11 auto byte_offset = view->ByteOffset();
12 auto byte_length = view->ByteLength();
13 assert(view->HasBuffer());
14 auto buffer = view->Buffer();
15 auto contents = buffer->GetBackingStore();
16 auto data = static_cast<unsigned char*>(contents->Data()) + byte_offset;
17
18 Bytef buf[1024];
19
20 z_stream stream;
21 stream.zalloc = nullptr;
22 stream.zfree = nullptr;
23
24 int err = deflateInit2(&stream, Z_DEFAULT_COMPRESSION, Z_DEFLATED,
25 -15, MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY);
26 assert(err == Z_OK);
27
28 stream.avail_in = byte_length;
29 stream.next_in = data;
30 stream.avail_out = sizeof(buf);
31 stream.next_out = buf;
32 err = deflate(&stream, Z_FINISH);
33 assert(err == Z_STREAM_END);
34
35 auto result = node::Buffer::Copy(info.GetIsolate(),
36 reinterpret_cast<const char*>(buf),
37 sizeof(buf) - stream.avail_out);
38
39 deflateEnd(&stream);
40
41 info.GetReturnValue().Set(result.ToLocalChecked());
42 }
43
Initialize(v8::Local<v8::Object> exports,v8::Local<v8::Value> module,v8::Local<v8::Context> context)44 inline void Initialize(v8::Local<v8::Object> exports,
45 v8::Local<v8::Value> module,
46 v8::Local<v8::Context> context) {
47 auto isolate = context->GetIsolate();
48 auto key = v8::String::NewFromUtf8(
49 isolate, "compressBytes").ToLocalChecked();
50 auto value = v8::FunctionTemplate::New(isolate, CompressBytes)
51 ->GetFunction(context)
52 .ToLocalChecked();
53 assert(exports->Set(context, key, value).IsJust());
54 }
55
56 } // anonymous namespace
57
58 NODE_MODULE_CONTEXT_AWARE(NODE_GYP_MODULE_NAME, Initialize)
59