[WIP] Provided file system from NACL.

ppapi/examples/filesystem_provider/filesystem.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <algorithm>
+#include <chrono>
+#include <deque>
+#include <map>
+#include <set>
+#include <sstream>
+#include <string.h>
+
+#include "memfilesystem.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/cpp/dev/filesystem_provider.h"
+#include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/module.h"
+#include "ppapi/cpp/var.h"
+#include "ppapi/utility/completion_callback_factory.h"
+#include "ppapi/cpp/input_event.h"
+
+namespace {
+template<class T>
+class FilesystemHelper {
+ public:
+  FilesystemHelper()
+      : callback_fact_(this) {
+    Init();
+  }
+  virtual ~FilesystemHelper(){}
+  virtual void OnUnmountRequest(int32_t request_id)=0;
+  virtual void OnMetadataRequest(
+      const std::string& file_path, bool thumbnail, int32_t request_id)=0;
+  virtual void OnReadDirectoryRequest(
+      const std::string& directory_path, int32_t request_id)=0;
+  virtual void OnOpenFileRequest(
+      const std::string& file_path, const PP_OpenFileMode_Dev& file_mode,
+      int32_t request_id)=0;
+  virtual void OnCloseFileRequest(
+      int32_t request_id, int32_t open_request_id)=0;
+  virtual void OnReadFileRequest(
+      int32_t open_request_id,
+      uint64_t offset,
+      uint64_t length,
+      int32_t request_id)=0;
+  virtual void OnCreateDirectoryRequest(
+      const std::string& directory_path,
+      bool recursive, int32_t request_id)=0;
+  virtual void OnDeleteEntryRequest(
+      const std::string& file_entry, bool recursive, int32_t request_id)=0;
+  virtual void OnCreateFileRequest(
+      const std::string& file_path, int32_t request_id)=0;
+  virtual void OnCopyEntryRequest(
+      const std::string& source_path,
+      const std::string& target_path,
+      int32_t request_id)=0;
+  virtual void OnMoveEntryRequest(
+      const std::string& source_path,
+      const std::string& target_path, int32_t request_id)=0;
+  virtual void OnTruncateRequest(
+      const std::string& file_path, int32_t offset, int32_t request_id)=0;
+  virtual void OnWriteRequest(int32_t, uint64_t, uint64_t,
+                              const char*, int32_t)=0;
+  virtual void OnAbortRequest(int32_t request_id, int32_t open_request_id)=0;
+ private:
+  bool Init(){
+    static_cast<T*>(this)->GetNextRequest(
+        callback_fact_.NewCallbackWithOutput(
+            &FilesystemHelper::OnRequestReceived));
+    return true;
+  }
+  // Dispatcher
+  void OnRequestReceived(int32_t result, PP_FilesystemRequest request){
+    if (result==PP_OK) {
+      switch (request.operation_type) {
+        case PP_OperationType_UNMOUNT:
+          static_cast<T*>(this)->OnUnmountRequest(request.request_id);
+          break;
+        case PP_OperationType_GETMETADATA:
+          static_cast<T*>(this)->OnMetadataRequest(
+              request.value.as_metadata.entry_path,
+              request.value.as_metadata.thumbnail,
+              request.request_id);
+          break;
+        case PP_OperationType_READDIRECTORY:
+          static_cast<T*>(this)->OnReadDirectoryRequest(
+                request.value.as_read_directory.directory_path,
+                request.request_id);
+          break;
+        case PP_OperationType_OPENFILE:
+          static_cast<T*>(this)->OnOpenFileRequest(
+                request.value.as_open_file.file_path,
+                request.value.as_open_file.mode, request.request_id);
+          break;
+        case PP_OperationType_CLOSEFILE:
+          static_cast<T*>(this)->OnCloseFileRequest(
+                request.value.as_close_file.open_request_id,
+                request.request_id);
+          break;
+        case PP_OperationType_READFILE:
+          static_cast<T*>(this)->OnReadFileRequest(
+                request.value.as_read_file.open_request_id,
+                request.value.as_read_file.offset,
+                request.value.as_read_file.length,
+                request.request_id);
+          break;
+        case PP_OperationType_CREATEDIRECTORY:
+          static_cast<T*>(this)->OnCreateDirectoryRequest(
+                request.value.as_create_directory.directory_path,
+                request.value.as_create_directory.recursive,
+                request.request_id);
+          break;
+        case PP_OperationType_DELETEENTRY:
+          static_cast<T*>(this)->OnDeleteEntryRequest(
+                request.value.as_delete_entry.entry_path,
+                request.value.as_delete_entry.recursive,request.request_id);
+          break;
+        case PP_OperationType_CREATEFILE:
+          static_cast<T*>(this)->OnCreateFileRequest(
+                request.value.as_create_file.file_path, request.request_id);
+          break;
+        case PP_OperationType_COPYENTRY:
+          static_cast<T*>(this)->OnCopyEntryRequest(
+                request.value.as_copy_entry.source_path,
+                request.value.as_copy_entry.target_path,
+                request.request_id);
+          break;
+        case PP_OperationType_MOVEENTRY:
+          static_cast<T*>(this)->OnMoveEntryRequest(
+                request.value.as_move_entry.source_path,
+                request.value.as_move_entry.target_path,
+                request.request_id);
+          break;
+        case PP_OperationType_TRUNCATEENTRY:
+          static_cast<T*>(this)->OnTruncateRequest(
+                request.value.as_truncate.file_path,
+                request.value.as_truncate.length,
+                request.request_id);
+          break;
+        case PP_OperationType_WRITEFILE:
+          static_cast<T*>(this)->OnWriteRequest(
+                request.value.as_write_file.open_request_id,
+                request.value.as_write_file.offset,
+                request.value.as_write_file.data_size,
+                (char*)request.value.as_write_file.data,
+                request.request_id);
+          break;
+        case PP_OperationType_ABORT:
+          static_cast<T*>(this)->OnAbortRequest(
+                request.value.as_abort.operation_request_id,
+                request.request_id);
+          break;
+        default:
+          break;
+      }
+    }
+    // Re-register the callback
+    static_cast<T*>(this)->GetNextRequest(
+          callback_fact_.NewCallbackWithOutput(
+              &FilesystemHelper::OnRequestReceived));
+  }
+ private:
+  pp::CompletionCallbackFactory< FilesystemHelper<T> > callback_fact_;
+};
+}// namespace
+class MyInstance :
+    public pp::Instance,
+    public pp::Filesystem_Provider_Dev,
+    public FilesystemHelper<MyInstance> {
+ public:
+  MyInstance(PP_Instance instance)
+      :pp::Instance(instance),
+      Filesystem_Provider_Dev(this),
+      callback_factory_(this),
+      filesystem_id_("in-memory-fs"),
+      display_name_("Test-Filesystem"),
+      mounted_(false) {
+    Initialize();
+  }
+
+virtual ~MyInstance() {
+}
+
+void Initialize() {
+  Mount(filesystem_id_, display_name_, true, 0,
+        callback_factory_.NewCallbackWithOutput(
+        &MyInstance::OnMountCompletion));
+}
+void OnMountCompletion(int32_t result, PP_ProviderError_Dev error ) {
+  if ( result!=PP_OK ||
+       error!=PP_ProviderError_OK) {
+    return;
+  }
+  mounted_ = true;
+}
+
+// Filesystem_Provider_Dev interfaces
+void OnUnmountRequest(int32_t request_id) {
+  // close connections, clean caches
+  SendSuccessResponse(PP_OperationType_UNMOUNT,request_id);
+}
+
+  void OnMetadataRequest(
+      const std::string &entry_path,
+      bool thumbnail, int32_t request_id) {
+
+    filesystem::Filesystem::NameInodePair meta;
+    if( filesystem_.GetMetadata(entry_path,meta)==
+        filesystem::Filesystem::File_System_Error_NOT_FOUND ) {
+      SendErrorResponse(
+         PP_OperationType_GETMETADATA,
+         PP_ProviderError_NOT_FOUND,
+         request_id );
+    } else {
+      PP_EntryMetadata_Dev metadata;
+      memset(&metadata, 0x0, sizeof(metadata));
+      metadata.is_directory = PP_FromBool(meta.second->file_type()==
+                                          filesystem::Inode::FILE_TYPE_DIR);
+      // Should check result
+      snprintf(metadata.name,
+               sizeof(metadata.name),
+               "%s", meta.first.c_str());
+      snprintf( metadata.modification_time,
+                sizeof(metadata.modification_time),
+                "%s",meta.second->file_modified().c_str());
+      metadata.size = meta.second->size();
+      SendMetadataSuccessResponse(metadata,request_id);
+    }
+  }
+
+  void OnReadDirectoryRequest(
+      const std::string &directory_path,
+      int32_t request_id) {
+    std::vector<filesystem::Filesystem::NameInodePair> metas;
+
+    if ( filesystem_.ReadDirectory(directory_path,metas)==
+         filesystem::Filesystem::File_System_Error_NONE ) {
+      std::vector<PP_EntryMetadata_Dev> metadatas;
+      PP_EntryMetadata_Dev metadata;
+      for(std::vector<filesystem::Filesystem::NameInodePair>::iterator
+          it = metas.begin();
+          it != metas.end();
+          ++it)
+      {
+        memset(&metadata, 0x0, sizeof(metadata));
+        metadata.is_directory = PP_FromBool(it->second->file_type()==
+                                              filesystem::Inode::FILE_TYPE_DIR);
+        snprintf(metadata.name,
+                 sizeof(metadata.name),
+                 "%s", it->first.c_str());
+        snprintf( metadata.modification_time,
+                  sizeof(metadata.modification_time),
+                  "%s",it->second->file_modified().c_str());
+        metadata.size = it->second->size();
+        metadatas.push_back(metadata);
+      }
+      SendReadDirectorySuccessResponse(metadatas,false, request_id);
+    } else {
+      SendErrorResponse(
+          PP_OperationType_READDIRECTORY,
+          PP_ProviderError_FAILED, request_id );
+    }
+  }
+  void OnOpenFileRequest(
+      const std::string &file_path,
+      const PP_OpenFileMode_Dev &mode,
+      int32_t request_id) {
+    filesystem::Filesystem::NameInodePair meta;
+    if (filesystem_.GetMetadata(file_path,meta)==
+       filesystem::Filesystem::File_System_Error_NONE) {
+      opened_files_.insert( std::pair<int,std::string>(request_id, file_path));
+      SendSuccessResponse(
+          PP_OperationType_OPENFILE,
+          request_id );
+    } else {
+      SendErrorResponse(
+          PP_OperationType_OPENFILE,
+          PP_ProviderError_FAILED,request_id);
+    }
+  }
+
+  void OnCloseFileRequest(int32_t open_request_id,int32_t request_id)  {
+    ListOfOpenedFilesIterator it = opened_files_.find(open_request_id);
+    if (it==opened_files_.end()) {// no open request
+      SendErrorResponse(
+          PP_OperationType_CLOSEFILE,
+          PP_ProviderError_FAILED,
+          request_id );
+    } else {
+      SendSuccessResponse(PP_OperationType_CLOSEFILE, request_id);
+    }
+  }
+
+  void OnReadFileRequest(
+      int32_t open_request_id,
+      uint64_t offset,
+      uint64_t length,
+      int32_t request_id)  {
+    ListOfOpenedFilesIterator it = opened_files_.find(open_request_id);
+    if (it==opened_files_.end()) {
+      SendErrorResponse(
+          PP_OperationType_READFILE,
+          PP_ProviderError_FAILED,
+          request_id);
+    } else {
+      size_t in_out_length=length;
+      const char *out_data = nullptr;
+      if(filesystem::Filesystem::File_System_Error_FAILED ==
+         filesystem_.ReadFromFile(
+            it->second,
+            offset,
+            &in_out_length, &out_data ) ) {
+        SendErrorResponse(
+            PP_OperationType_READFILE,
+            PP_ProviderError_FAILED,
+            request_id);
+      } else {
+        SendReadFileSuccessResponse(
+            in_out_length, out_data, false, request_id );
+      }
+    }
+  }
+  void OnCreateDirectoryRequest (
+      const std::string &directory_path,
+      bool recursive, int32_t request_id)  {
+    if(filesystem::Filesystem::File_System_Error_NONE ==
+       filesystem_.CreateDirectory(directory_path,recursive))
+      SendSuccessResponse(PP_OperationType_CREATEDIRECTORY,request_id);
+    else
+      SendErrorResponse(PP_OperationType_CREATEDIRECTORY,
+                            PP_ProviderError_FAILED, request_id);
+  }
+  void OnDeleteEntryRequest(
+      const std::string &entry_path,
+      bool recursive, int32_t request_id)  {
+
+    if(filesystem::Filesystem::File_System_Error_NONE==
+       filesystem_.DeleteEntry(entry_path,recursive))
+      SendSuccessResponse(PP_OperationType_DELETEENTRY,request_id);
+    else
+      SendErrorResponse(
+          PP_OperationType_DELETEENTRY,
+          PP_ProviderError_NOT_FOUND,
+          request_id);
+  }
+
+  void OnCreateFileRequest(
+      const std::string &file_path, int32_t request_id)  {
+    if(filesystem::Filesystem::File_System_Error_NONE==
+       filesystem_.CreateFile(file_path))
+      SendSuccessResponse(PP_OperationType_CREATEFILE,request_id);
+    else
+      SendErrorResponse(
+          PP_OperationType_CREATEFILE,
+          PP_ProviderError_FAILED,
+          request_id);
+  }
+  void OnCopyEntryRequest(
+      const std::string &source_path,
+      const std::string &target_path,
+      int32_t request_id)  {
+    if(filesystem::Filesystem::File_System_Error_NONE==
+       filesystem_.CopyEntry(source_path,target_path))
+      SendSuccessResponse(PP_OperationType_COPYENTRY,request_id);
+    else
+      SendErrorResponse(PP_OperationType_COPYENTRY,
+                            PP_ProviderError_FAILED, request_id );
+  }
+  void OnMoveEntryRequest(
+      const std::string &source_path,
+      const std::string &target_path,
+      int32_t request_id)  {
+    if ( filesystem::Filesystem::File_System_Error_NONE==
+         filesystem_.MoveEntry(source_path,target_path))
+      SendSuccessResponse(PP_OperationType_MOVEENTRY, request_id);
+    else
+      SendErrorResponse(
+          PP_OperationType_MOVEENTRY,
+          PP_ProviderError_FAILED,
+          request_id );
+  }
+  void OnTruncateRequest(
+      const std::string &file_path,
+      int32_t length,
+      int32_t request_id)  {
+    if (filesystem::Filesystem::File_System_Error_NONE==
+        filesystem_.Truncate(file_path, length))
+      SendSuccessResponse(PP_OperationType_TRUNCATEENTRY,request_id);
+    else
+      SendErrorResponse(PP_OperationType_TRUNCATEENTRY,
+                            PP_ProviderError_FAILED,request_id );
+  }
+  void OnWriteRequest(int32_t open_request_id, uint64_t offset,
+                          uint64_t data_size, const char *data,
+                          int32_t request_id)  {
+    ListOfOpenedFilesIterator it = opened_files_.find(open_request_id);
+    if (it==opened_files_.end()){
+      SendErrorResponse(
+          PP_OperationType_WRITEFILE,
+          PP_ProviderError_FAILED,
+          request_id);
+    } else {
+      if (filesystem::Filesystem::File_System_Error_NONE!=
+          filesystem_.WriteToFile(it->second, offset, data_size, data)) {
+        SendErrorResponse(
+            PP_OperationType_WRITEFILE,
+            PP_ProviderError_FAILED,
+            request_id );
+      } else {
+        SendSuccessResponse(PP_OperationType_WRITEFILE,request_id);
+      }
+    }
+    // Free buffer
+    FreeWriteRequestBuffer(data);
+  }
+  void OnAbortRequest(
+      int32_t operation_request_id, int32_t request_id)  {
+    SendSuccessResponse(PP_OperationType_ABORT,request_id);
+  }
+ private:
+  typedef std::map<int,std::string>    ListOfOpenedFiles;
+  typedef ListOfOpenedFiles::iterator  ListOfOpenedFilesIterator;
+  ListOfOpenedFiles opened_files_;
+  pp::CompletionCallbackFactory<MyInstance> callback_factory_;
+  // Filesystem properties
+  filesystem::Filesystem filesystem_;
+  std::string filesystem_id_;
+  std::string display_name_;
+  bool mounted_;
+};
+
+class MyModule : public pp::Module {
+ public:
+  virtual pp::Instance* CreateInstance(PP_Instance instance) {
+    return new MyInstance(instance);
+  }
+};
+
+namespace pp {
+
+// Factory function for your specialization of the Module object.
+Module* CreateModule() {
+  return new MyModule();
+}
+
+}  // namespace pp