node/src/node_stat_watcher.cc

#include "node_stat_watcher.h"
#include "async-wrap.h"
#include "async-wrap-inl.h"
#include "env.h"
#include "env-inl.h"
#include "util.h"
#include "util-inl.h"

#include <string.h>
#include <stdlib.h>

namespace node {

using v8::Context;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Integer;
using v8::Local;
using v8::Object;
using v8::Value;


void StatWatcher::Initialize(Environment* env, Local<Object> target) {
  HandleScope scope(env->isolate());

  Local<FunctionTemplate> t = env->NewFunctionTemplate(StatWatcher::New);
  t->InstanceTemplate()->SetInternalFieldCount(1);
  t->SetClassName(FIXED_ONE_BYTE_STRING(env->isolate(), "StatWatcher"));

  env->SetProtoMethod(t, "start", StatWatcher::Start);
  env->SetProtoMethod(t, "stop", StatWatcher::Stop);

  target->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "StatWatcher"),
              t->GetFunction());
}


static void Delete(uv_handle_t* handle) {
  delete reinterpret_cast<uv_fs_poll_t*>(handle);
}


StatWatcher::StatWatcher(Environment* env, Local<Object> wrap)
    : AsyncWrap(env, wrap, AsyncWrap::PROVIDER_STATWATCHER),
      watcher_(new uv_fs_poll_t) {
  MakeWeak<StatWatcher>(this);
  uv_fs_poll_init(env->event_loop(), watcher_);
  watcher_->data = static_cast<void*>(this);
}


StatWatcher::~StatWatcher() {
  Stop();
  uv_close(reinterpret_cast<uv_handle_t*>(watcher_), Delete);
}


void StatWatcher::Callback(uv_fs_poll_t* handle,
                           int status,
                           const uv_stat_t* prev,
                           const uv_stat_t* curr) {
  StatWatcher* wrap = static_cast<StatWatcher*>(handle->data);
  CHECK_EQ(wrap->watcher_, handle);
  Environment* env = wrap->env();
  HandleScope handle_scope(env->isolate());
  Context::Scope context_scope(env->context());
  Local<Value> argv[] = {
    BuildStatsObject(env, curr),
    BuildStatsObject(env, prev),
    Integer::New(env->isolate(), status)
  };
  wrap->MakeCallback(env->onchange_string(), ARRAY_SIZE(argv), argv);
}


void StatWatcher::New(const FunctionCallbackInfo<Value>& args) {
  CHECK(args.IsConstructCall());
  Environment* env = Environment::GetCurrent(args);
  new StatWatcher(env, args.This());
}


void StatWatcher::Start(const FunctionCallbackInfo<Value>& args) {
  CHECK_EQ(args.Length(), 3);

  StatWatcher* wrap = Unwrap<StatWatcher>(args.Holder());
  node::Utf8Value path(args.GetIsolate(), args[0]);
  const bool persistent = args[1]->BooleanValue();
  const uint32_t interval = args[2]->Uint32Value();

  if (!persistent)
    uv_unref(reinterpret_cast<uv_handle_t*>(wrap->watcher_));
  uv_fs_poll_start(wrap->watcher_, Callback, *path, interval);
  wrap->ClearWeak();
}


void StatWatcher::Stop(const FunctionCallbackInfo<Value>& args) {
  StatWatcher* wrap = Unwrap<StatWatcher>(args.Holder());
  Environment* env = wrap->env();
  Context::Scope context_scope(env->context());
  wrap->MakeCallback(env->onstop_string(), 0, nullptr);
  wrap->Stop();
}


void StatWatcher::Stop() {
  if (!uv_is_active(reinterpret_cast<uv_handle_t*>(watcher_)))
    return;
  uv_fs_poll_stop(watcher_);
  MakeWeak<StatWatcher>(this);
}


}  // namespace node