| // Copyright Joyent, Inc. and other Node contributors. |
| // |
| // Permission is hereby granted, free of charge, to any person obtaining a |
| // copy of this software and associated documentation files (the |
| // "Software"), to deal in the Software without restriction, including |
| // without limitation the rights to use, copy, modify, merge, publish, |
| // distribute, sublicense, and/or sell copies of the Software, and to permit |
| // persons to whom the Software is furnished to do so, subject to the |
| // following conditions: |
| // |
| // The above copyright notice and this permission notice shall be included |
| // in all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN |
| // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, |
| // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
| // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
| // USE OR OTHER DEALINGS IN THE SOFTWARE. |
| |
| #include "v8.h" |
| #include "node.h" |
| #include "node_buffer.h" |
| #include "slab_allocator.h" |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <assert.h> |
| |
| |
| using v8::Handle; |
| using v8::HandleScope; |
| using v8::Integer; |
| using v8::Local; |
| using v8::Null; |
| using v8::Object; |
| using v8::Persistent; |
| using v8::String; |
| using v8::Value; |
| using v8::V8; |
| |
| |
| namespace node { |
| |
| SlabAllocator::SlabAllocator(unsigned int size) { |
| size_ = ROUND_UP(size ? size : 1, 8192); |
| initialized_ = false; |
| } |
| |
| |
| SlabAllocator::~SlabAllocator() { |
| if (!initialized_) return; |
| if (V8::IsDead()) return; |
| slab_sym_.Dispose(); |
| slab_sym_.Clear(); |
| slab_.Dispose(); |
| slab_.Clear(); |
| } |
| |
| |
| void SlabAllocator::Initialize() { |
| HandleScope scope; |
| char sym[256]; |
| snprintf(sym, sizeof(sym), "slab_%p", this); // namespace object key |
| offset_ = 0; |
| last_ptr_ = NULL; |
| initialized_ = true; |
| slab_sym_ = Persistent<String>::New(String::New(sym)); |
| } |
| |
| |
| static Local<Object> NewSlab(unsigned int size) { |
| HandleScope scope; |
| Local<Value> arg = Integer::NewFromUnsigned(ROUND_UP(size, 16)); |
| Local<Object> buf = Buffer::constructor_template |
| ->GetFunction() |
| ->NewInstance(1, &arg); |
| return scope.Close(buf); |
| } |
| |
| |
| char* SlabAllocator::Allocate(Handle<Object> obj, unsigned int size) { |
| HandleScope scope; |
| |
| assert(!obj.IsEmpty()); |
| |
| if (size == 0) return NULL; |
| if (!initialized_) Initialize(); |
| |
| if (size > size_) { |
| Local<Object> buf = NewSlab(size); |
| obj->SetHiddenValue(slab_sym_, buf); |
| return Buffer::Data(buf); |
| } |
| |
| if (slab_.IsEmpty() || offset_ + size > size_) { |
| slab_.Dispose(); |
| slab_.Clear(); |
| slab_ = Persistent<Object>::New(NewSlab(size_)); |
| offset_ = 0; |
| last_ptr_ = NULL; |
| } |
| |
| obj->SetHiddenValue(slab_sym_, slab_); |
| last_ptr_ = Buffer::Data(slab_) + offset_; |
| offset_ += size; |
| |
| return last_ptr_; |
| } |
| |
| |
| Local<Object> SlabAllocator::Shrink(Handle<Object> obj, |
| char* ptr, |
| unsigned int size) { |
| HandleScope scope; |
| Local<Value> slab_v = obj->GetHiddenValue(slab_sym_); |
| obj->SetHiddenValue(slab_sym_, Null()); |
| assert(!slab_v.IsEmpty()); |
| assert(slab_v->IsObject()); |
| Local<Object> slab = slab_v->ToObject(); |
| assert(ptr != NULL); |
| if (ptr == last_ptr_) { |
| last_ptr_ = NULL; |
| offset_ = ptr - Buffer::Data(slab) + ROUND_UP(size, 16); |
| } |
| return scope.Close(slab); |
| } |
| |
| |
| } // namespace node |