Cheevos: Implement hrash VFS API

CMakeLists.txt

@@ -25,6 +25,8 @@ set(LIBRETRO_SOURCES src/client.cpp
                      src/audio/AudioStream.cpp
                      src/audio/SingleFrameAudio.cpp
                      src/cheevos/Cheevos.cpp
+                     src/cheevos/CheevosEnvironment.cpp
+                     src/cheevos/CheevosFrontendBridge.cpp
                      src/GameInfoLoader.cpp
                      src/input/ButtonMapper.cpp
                      src/input/ControllerLayout.cpp

src/cheevos/CheevosEnvironment.cpp

@@ -0,0 +1,36 @@
+/*
+ *  Copyright (C) 2020 Team Kodi (https://kodi.tv)
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSE.md for more information.
+ */
+
+#include "CheevosEnvironment.h"
+#include "CheevosFrontendBridge.h"
+
+#include <rcheevos/rhash.h>
+
+using namespace LIBRETRO;
+
+CCheevosEnvironment& CCheevosEnvironment::Get(void)
+{
+  static CCheevosEnvironment _instance;
+  return _instance;
+}
+
+void CCheevosEnvironment::Initialize()
+{
+  static rc_hash_filereader fileReader = {
+    CCheevosFrontendBridge::OpenFile,
+    CCheevosFrontendBridge::Seek,
+    CCheevosFrontendBridge::GetPosition,
+    CCheevosFrontendBridge::ReadFile,
+    CCheevosFrontendBridge::CloseFile,
+  };
+
+  rc_hash_init_custom_filereader(&fileReader);
+}
+
+void CCheevosEnvironment::Deinitialize()
+{
+}

src/cheevos/CheevosEnvironment.h

@@ -0,0 +1,24 @@
+/*
+ *  Copyright (C) 2020 Team Kodi (https://kodi.tv)
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSE.md for more information.
+ */
+
+#pragma once
+
+namespace LIBRETRO
+{
+  class CCheevosEnvironment
+  {
+  public:
+    static CCheevosEnvironment& Get(void);
+
+    void Initialize();
+
+    void Deinitialize();
+
+  private:
+    CCheevosEnvironment() = default;
+  };
+} // namespace LIBRETRO

src/cheevos/CheevosFrontendBridge.cpp

@@ -0,0 +1,110 @@
+/*
+ *  Copyright (C) 2020 Team Kodi (https://kodi.tv)
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSE.md for more information.
+ */
+
+#include "CheevosFrontendBridge.h"
+
+#include <kodi/Filesystem.h>
+#include <stdio.h>
+
+using namespace LIBRETRO;
+
+void *CCheevosFrontendBridge::OpenFile(const char* path_utf8)
+{
+  // Return NULL for error
+  if (path_utf8 == nullptr)
+    return nullptr;
+
+  // TODO: Handle UTF-8?
+  std::unique_ptr<FileHandle> fileHandle(new FileHandle{ path_utf8 });
+  fileHandle->file.reset(new kodi::vfs::CFile);
+
+  if (!fileHandle->file->OpenFile(fileHandle->path, 0))
+    return nullptr;
+
+  // Return the opaque file handle on success
+  return static_cast<void*>(fileHandle.release());
+}
+
+void CCheevosFrontendBridge::CloseFile(void* file_handle)
+{
+  if (file_handle == nullptr)
+    return;
+
+  FileHandle *fileHandle = static_cast<FileHandle*>(file_handle);
+
+  fileHandle->file->Close();
+  delete fileHandle;
+}
+
+size_t CCheevosFrontendBridge::GetPosition(void* file_handle)
+{
+  // Return 0 for error
+  if (file_handle == nullptr)
+    return 0;
+
+  FileHandle *fileHandle = static_cast<FileHandle*>(file_handle);
+
+  const int64_t currentPosition = fileHandle->file->GetPosition();
+
+  if (currentPosition < 0)
+    return 0;
+
+  // Return the current read / write position for the file
+  return currentPosition;
+}
+
+void CCheevosFrontendBridge::Seek(void* file_handle, size_t offset, int origin)
+{
+  if (file_handle == nullptr)
+    return;
+
+  FileHandle *fileHandle = static_cast<FileHandle*>(file_handle);
+
+  int whence = -1;
+
+  switch (origin)
+  {
+  case 0:
+    whence = SEEK_SET;
+    break;
+  case 1:
+    whence = SEEK_CUR;
+    break;
+  case 2:
+    whence = SEEK_END;
+    break;
+  default:
+    break;
+  }
+
+  if (whence == -1)
+    return;
+
+  fileHandle->file->Seek(offset, whence);
+}
+
+size_t CCheevosFrontendBridge::ReadFile(void* file_handle, void* buffer, size_t requested_bytes)
+{
+  // Return 0 for error
+  if (file_handle == nullptr)
+    return 0;
+
+  FileHandle *fileHandle = static_cast<FileHandle*>(file_handle);
+
+  const ssize_t bytesRead = fileHandle->file->Read(buffer, requested_bytes);
+
+  if (bytesRead < 0)
+    return 0;
+
+  // Return 0 if no bytes are available to read (end of file was reached) or
+  // undetectable error occurred
+  if (bytesRead == 0)
+    return 0;
+
+  // Return the number of bytes read
+  return static_cast<size_t>(bytesRead);
+}

src/cheevos/CheevosFrontendBridge.h

@@ -0,0 +1,47 @@
+/*
+ *  Copyright (C) 2020 Team Kodi (https://kodi.tv)
+ *
+ *  SPDX-License-Identifier: GPL-2.0-or-later
+ *  See LICENSE.md for more information.
+ */
+
+#pragma once
+
+#include <memory>
+#include <rcheevos/rhash.h>
+#include <string>
+
+namespace kodi
+{
+namespace vfs
+{
+  class CFile;
+}
+}
+
+namespace LIBRETRO
+{
+  /*!
+   * Provide a bridge for frontend callbacks given to the rcheevos library.
+   *
+   * These functions are given to the rcheevos library in
+   * CheevosEnvironment::Initialize().
+   */
+  class CCheevosFrontendBridge
+  {
+  public:
+    // Forward to Kodi VFS API
+    static void *OpenFile(const char* path_utf8);
+    static void CloseFile(void* file_handle);
+    static size_t GetPosition(void* file_handle);
+    static void Seek(void* file_handle, size_t offset, int origin);
+    static size_t ReadFile(void* file_handle, void* buffer, size_t requested_bytes);
+
+  private:
+    struct FileHandle
+    {
+      std::string path;
+      std::unique_ptr<kodi::vfs::CFile> file;
+    };
+  };
+} // namespace LIBRETRO

src/client.cpp

@@ -6,6 +6,7 @@
  */
 
 #include "cheevos/Cheevos.h"
+#include "cheevos/CheevosEnvironment.h"
 #include "input/ButtonMapper.h"
 #include "input/ControllerTopology.h"
 #include "input/InputManager.h"
@@ -51,6 +52,7 @@ CGameLibRetro::~CGameLibRetro()
   CControllerTopology::GetInstance().Clear();
 
   CLibretroEnvironment::Get().Deinitialize();
+  CCheevosEnvironment::Get().Deinitialize();
 
   CCheevos::Get().Deinitialize();
 
@@ -82,6 +84,7 @@ ADDON_STATUS CGameLibRetro::Create()
 
     // Environment must be initialized before calling retro_init()
     CLibretroEnvironment::Get().Initialize(this, &m_client, &m_clientBridge);
+    CCheevosEnvironment::Get().Initialize();
 
     CButtonMapper::Get().LoadButtonMap();
     CControllerTopology::GetInstance().LoadTopology();