Implement File API

src/FileSystemJsObject.cpp

Index: src/FileSystemJsObject.cpp
===================================================================
new file mode 100644
--- /dev/null
+++ b/src/FileSystemJsObject.cpp
@@ -0,0 +1,370 @@
+#include <AdblockPlus/FileSystem.h>
+#include <stdexcept>
+#include <sstream>
+#include <vector>
+
+#include "FileSystemJsObject.h"
+#include "Utils.h"
+#include "Thread.h"
+#include "Utils.h"
+
+using namespace AdblockPlus;
+
+namespace
+{
+  class IoThread : public Thread
+  {
+  public:
+    IoThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback)
+      : isolate(v8::Isolate::GetCurrent()),
+        context(v8::Persistent<v8::Context>::New(isolate,
+                                                 v8::Context::GetCurrent())),
+        fileSystem(fileSystem),
+        callback(v8::Persistent<v8::Function>::New(isolate, callback))
+    {
+    }
+
+    virtual ~IoThread()
+    {
+      callback.Dispose(isolate);
+      context.Dispose(isolate);
+    }
+
+  protected:
+    v8::Isolate* const isolate;
+    v8::Persistent<v8::Context> context;
+    FileSystem& fileSystem;
+    v8::Persistent<v8::Function> callback;
+  };
+
+  class ReadThread : public IoThread
+  {
+  public:
+    ReadThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback,
+               const std::string& path)
+      : IoThread(fileSystem, callback), path(path)
+    {
+    }
+
+    void Run()
+    {
+      std::string content;
+      std::string error;
+      try
+      {
+        std::tr1::shared_ptr<std::istream> stream = fileSystem.Read(path);
+        content = Utils::Slurp(*stream);
+      }
+      catch (std::exception& e)
+      {
+        error = e.what();
+      }
+      catch (...)
+      {
+        error =  "Unknown error while reading from " + path;
+      }
+
+      const v8::Locker locker(isolate);
+      const v8::HandleScope handleScope;
+      const v8::Context::Scope contextScope(context);
+      v8::Handle<v8::Object> result = v8::Object::New();
+      result->Set(v8::String::New("content"), Utils::ToV8String(content));
+      result->Set(v8::String::New("error"), Utils::ToV8String(error));
+      callback->Call(callback, 1,
+                     reinterpret_cast<v8::Handle<v8::Value>*>(&result));
+      delete this;
+    }
+
+  private:
+    std::string path;
+  };
+
+  class WriteThread : public IoThread
+  {
+  public:
+    WriteThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback,
+                const std::string& path, const std::string& content)
+      : IoThread(fileSystem, callback), path(path), content(content)
+    {
+    }
+
+    void Run()
+    {
+      std::string error;
+      try
+      {
+        std::tr1::shared_ptr<std::ostream> stream(new std::stringstream);
+        *stream << content;
+        fileSystem.Write(path, stream);
+      }
+      catch (std::exception& e)
+      {
+        error = e.what();
+      }
+      catch (...)
+      {
+        error = "Unknown error while writing to " + path;
+      }
+
+      const v8::Locker locker(isolate);
+      const v8::HandleScope handleScope;
+      const v8::Context::Scope contextScope(context);
+      v8::Handle<v8::Value> errorValue = Utils::ToV8String(error);
+      callback->Call(callback, 1, &errorValue);
+      delete this;
+    }
+
+  private:
+    std::string path;
+    std::string content;
+  };
+
+  class MoveThread : public IoThread
+  {
+  public:
+    MoveThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback,
+               const std::string& fromPath, const std::string& toPath)
+      : IoThread(fileSystem, callback), fromPath(fromPath), toPath(toPath)
+    {
+    }
+
+    void Run()
+    {
+      std::string error;
+      try
+      {
+        fileSystem.Move(fromPath, toPath);
+      }
+      catch (std::exception& e)
+      {
+        error = e.what();
+      }
+      catch (...)
+      {
+        error = "Unknown error while moving " + fromPath + " to " + toPath;
+      }
+
+      const v8::Locker locker(isolate);
+      const v8::HandleScope handleScope;
+      const v8::Context::Scope contextScope(context);
+      v8::Handle<v8::Value> errorValue = Utils::ToV8String(error);
+      callback->Call(callback, 1, &errorValue);
+      delete this;
+    }
+
+  private:
+    std::string fromPath;
+    std::string toPath;
+  };
+
+  class RemoveThread : public IoThread
+  {
+  public:
+    RemoveThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback,
+                 const std::string& path)
+      : IoThread(fileSystem, callback), path(path)
+    {
+    }
+
+    void Run()
+    {
+      std::string error;
+      try
+      {
+        fileSystem.Remove(path);
+      }
+      catch (std::exception& e)
+      {
+        error = e.what();
+      }
+      catch (...)
+      {
+        error = "Unknown error while removing " + path;
+      }
+
+      const v8::Locker locker(isolate);
+      const v8::HandleScope handleScope;
+      const v8::Context::Scope contextScope(context);
+      v8::Handle<v8::Value> errorValue = Utils::ToV8String(error);
+      callback->Call(callback, 1, &errorValue);
+      delete this;
+    }
+
+  private:
+    std::string path;
+  };
+
+  class StatThread : public IoThread
+  {
+  public:
+    StatThread(FileSystem& fileSystem, v8::Handle<v8::Function> callback,
+               const std::string& path)
+      : IoThread(fileSystem, callback), path(path)
+    {
+    }
+
+    void Run()
+    {
+      std::string error;
+      FileSystem::StatResult statResult;
+      try
+      {
+        statResult = fileSystem.Stat(path);
+      }
+      catch (std::exception& e)
+      {
+        error = e.what();
+      }
+      catch (...)
+      {
+        error = "Unknown error while calling stat on " + path;
+      }
+
+      const v8::Locker locker(isolate);
+      const v8::HandleScope handleScope;
+      const v8::Context::Scope contextScope(context);
+      v8::Handle<v8::Object> result = v8::Object::New();
+      result->Set(v8::String::New("exists"),
+                  v8::Boolean::New(statResult.exists));
+      result->Set(v8::String::New("isFile"),
+                  v8::Boolean::New(statResult.isFile));
+      result->Set(v8::String::New("isDirectory"),
+                  v8::Boolean::New(statResult.isDirectory));
+      result->Set(v8::String::New("lastModified"),
+                  v8::Integer::New(statResult.lastModified));
+      result->Set(v8::String::New("error"), Utils::ToV8String(error));
+      callback->Call(callback, 1,
+                     reinterpret_cast<v8::Handle<v8::Value>*>(&result));
+      delete this;
+    }
+
+  private:
+    std::string path;
+  };
+
+  v8::Handle<v8::Value> ReadCallback(const v8::Arguments& arguments)
+  {
+    const v8::Handle<const v8::External> external =
+      v8::Handle<const v8::External>::Cast(arguments.Data());
+    FileSystem* const fileSystem = static_cast<FileSystem*>(external->Value());
+    if (!arguments.Length() == 2)

[Wladimir Palant, 2013/04/16 13:03:41]

Does this actually work? :)
arguments.Length() != 2

[Felix Dahlke, 2013/04/16 14:00:09]

lol, yeah it does, but it sure is weird :) Fixed it here and below.

[Wladimir Palant, 2013/04/16 14:10:13]

Weird operator precedence rules then...

+      return v8::ThrowException(v8::String::New(
+        "_fileSystem.read requires 2 parameters"));
+    const std::string path = Utils::FromV8String(arguments[0]);
+    v8::Handle<v8::Value> callbackValue = arguments[1];
+    if (!callbackValue->IsFunction())
+      return v8::ThrowException(v8::String::New(
+        "Second argument to _fileSystem.read must be a function"));
+    v8::Handle<v8::Function> callback =
+      v8::Handle<v8::Function>::Cast(callbackValue);
+    ReadThread* const readThread = new ReadThread(*fileSystem, callback, path);
+    readThread->Start();
+    return v8::Undefined();
+  }
+
+  v8::Handle<v8::Value> WriteCallback(const v8::Arguments& arguments)
+  {
+    const v8::Handle<const v8::External> external =
+      v8::Handle<const v8::External>::Cast(arguments.Data());
+    FileSystem* const fileSystem = static_cast<FileSystem*>(external->Value());
+    if (!arguments.Length() == 3)
+      return v8::ThrowException(v8::String::New(
+        "_fileSystem.write requires 3 parameters"));
+    const std::string path = Utils::FromV8String(arguments[0]);
+    const std::string content = Utils::FromV8String(arguments[1]);
+    v8::Handle<v8::Value> callbackValue = arguments[2];
+    if (!callbackValue->IsFunction())
+      return v8::ThrowException(v8::String::New(
+        "Third argument to _fileSystem.write must be a function"));
+    v8::Handle<v8::Function> callback =
+      v8::Handle<v8::Function>::Cast(callbackValue);
+    WriteThread* const writeThread = new WriteThread(*fileSystem, callback,
+                                                     path, content);
+    writeThread->Start();
+    return v8::Undefined();
+  }
+
+  v8::Handle<v8::Value> MoveCallback(const v8::Arguments& arguments)
+  {
+    const v8::Handle<const v8::External> external =
+      v8::Handle<const v8::External>::Cast(arguments.Data());
+    FileSystem* const fileSystem = static_cast<FileSystem*>(external->Value());
+    if (!arguments.Length() == 3)
+      return v8::ThrowException(v8::String::New(
+        "_fileSystem.move requires 3 parameters"));
+    const std::string fromPath = Utils::FromV8String(arguments[0]);
+    const std::string toPath = Utils::FromV8String(arguments[1]);
+    v8::Handle<v8::Value> callbackValue = arguments[2];
+    if (!callbackValue->IsFunction())
+      return v8::ThrowException(v8::String::New(
+        "Third argument to _fileSystem.move must be a function"));
+    v8::Handle<v8::Function> callback =
+      v8::Handle<v8::Function>::Cast(callbackValue);
+    MoveThread* const moveThread = new MoveThread(*fileSystem, callback,
+                                                  fromPath, toPath);
+    moveThread->Start();
+    return v8::Undefined();
+  }
+
+  v8::Handle<v8::Value> RemoveCallback(const v8::Arguments& arguments)
+  {
+    const v8::Handle<const v8::External> external =
+      v8::Handle<const v8::External>::Cast(arguments.Data());
+    FileSystem* const fileSystem = static_cast<FileSystem*>(external->Value());
+    if (!arguments.Length() == 2)
+      return v8::ThrowException(v8::String::New(
+        "_fileSystem.remove requires 2 parameters"));
+    const std::string path = Utils::FromV8String(arguments[0]);
+    v8::Handle<v8::Value> callbackValue = arguments[1];
+    if (!callbackValue->IsFunction())
+      return v8::ThrowException(v8::String::New(
+        "Second argument to _fileSystem.remove must be a function"));
+    v8::Handle<v8::Function> callback =
+      v8::Handle<v8::Function>::Cast(callbackValue);
+    RemoveThread* const removeThread = new RemoveThread(*fileSystem, callback,
+                                                        path);
+    removeThread->Start();
+    return v8::Undefined();
+  }
+
+  v8::Handle<v8::Value> StatCallback(const v8::Arguments& arguments)
+  {
+    const v8::Handle<const v8::External> external =
+      v8::Handle<const v8::External>::Cast(arguments.Data());
+    FileSystem* const fileSystem = static_cast<FileSystem*>(external->Value());
+    if (!arguments.Length() == 2)
+      return v8::ThrowException(v8::String::New(
+        "_fileSystem.stat requires 2 parameters"));
+    const std::string path = Utils::FromV8String(arguments[0]);
+    v8::Handle<v8::Value> callbackValue = arguments[1];
+    if (!callbackValue->IsFunction())
+      return v8::ThrowException(v8::String::New(
+        "Second argument to _fileSystem.stat must be a function"));
+    v8::Handle<v8::Function> callback =
+      v8::Handle<v8::Function>::Cast(callbackValue);
+    StatThread* const statThread = new StatThread(*fileSystem, callback, path);
+    statThread->Start();
+    return v8::Undefined();
+  }
+}
+
+v8::Handle<v8::ObjectTemplate>
+FileSystemJsObject::Create(FileSystem& fileSystem)
+{
+  const v8::Locker locker(v8::Isolate::GetCurrent());
+  v8::HandleScope handleScope;
+  const v8::Handle<v8::ObjectTemplate> file = v8::ObjectTemplate::New();
+  const v8::Local<v8::External> fileSystemExternal =
+    v8::External::New(&fileSystem);
+  file->Set(v8::String::New("read"),
+            v8::FunctionTemplate::New(ReadCallback, fileSystemExternal));
+  file->Set(v8::String::New("write"),
+            v8::FunctionTemplate::New(WriteCallback, fileSystemExternal));
+  file->Set(v8::String::New("move"),
+            v8::FunctionTemplate::New(MoveCallback, fileSystemExternal));
+  file->Set(v8::String::New("remove"),
+            v8::FunctionTemplate::New(RemoveCallback, fileSystemExternal));
+  file->Set(v8::String::New("stat"),
+            v8::FunctionTemplate::New(StatCallback, fileSystemExternal));
+  return handleScope.Close(file);
+}