windows_pi.cpp

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//==---------------- windows_pi.cpp ----------------------------------------==//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
 
#include <sycl/backend.hpp>
#include <sycl/detail/defines.hpp>
 
#include <cassert>
#include <string>
#include <windows.h>
#include <winreg.h>
 
#include "detail/windows_os_utils.hpp"
#include "pi_win_proxy_loader.hpp"
 
namespace sycl {
inline namespace _V1 {
namespace detail {
namespace pi {
 
void *loadOsLibrary(const std::string &LibraryPath) {
  // Tells the system to not display the critical-error-handler message box.
  // Instead, the system sends the error to the calling process.
  // This is crucial for graceful handling of shared libs that can't be
  // loaded, e.g. due to missing native run-times.
 
  UINT SavedMode = SetErrorMode(SEM_FAILCRITICALERRORS);
  // Exclude current directory from DLL search path
  if (!SetDllDirectoryA("")) {
    assert(false && "Failed to update DLL search path");
  }
 
  auto Result = (void *)LoadLibraryExA(LibraryPath.c_str(), NULL, NULL);
  (void)SetErrorMode(SavedMode);
  if (!SetDllDirectoryA(nullptr)) {
    assert(false && "Failed to restore DLL search path");
  }
 
  return Result;
}
 
void *loadOsPluginLibrary(const std::string &PluginPath) {
  // We fetch the preloaded plugin from the pi_win_proxy_loader.
  // The proxy_loader handles any required error suppression.
  auto Result = getPreloadedPlugin(PluginPath);
 
  return Result;
}
 
int unloadOsLibrary(void *Library) {
  return (int)FreeLibrary((HMODULE)Library);
}
 
int unloadOsPluginLibrary(void *Library) {
  // The mock plugin does not have an associated library, so we allow nullptr
  // here to avoid it trying to free a non-existent library.
  if (!Library)
    return 1;
  return (int)FreeLibrary((HMODULE)Library);
}
 
void *getOsLibraryFuncAddress(void *Library, const std::string &FunctionName) {
  return reinterpret_cast<void *>(
      GetProcAddress((HMODULE)Library, FunctionName.c_str()));
}
 
static std::filesystem::path getCurrentDSODirPath() {
  wchar_t Path[MAX_PATH];
  auto Handle =
      getOSModuleHandle(reinterpret_cast<void *>(&getCurrentDSODirPath));
  DWORD Ret = GetModuleFileName(
      reinterpret_cast<HMODULE>(ExeModuleHandle == Handle ? 0 : Handle), Path,
      MAX_PATH);
  assert(Ret < MAX_PATH && "Path is longer than MAX_PATH?");
  assert(Ret > 0 && "GetModuleFileName failed");
  (void)Ret;
 
  BOOL RetCode = PathRemoveFileSpec(Path);
  assert(RetCode && "PathRemoveFileSpec failed");
  (void)RetCode;
 
  return std::filesystem::path(Path);
}
 
// Load plugins corresponding to provided list of plugin names.
std::vector<std::tuple<std::string, backend, void *>>
loadPlugins(const std::vector<std::pair<std::string, backend>> &&PluginNames) {
  std::vector<std::tuple<std::string, backend, void *>> LoadedPlugins;
  const std::filesystem::path LibSYCLDir = getCurrentDSODirPath();
 
  for (auto &PluginName : PluginNames) {
    void *Library = getPreloadedPlugin(LibSYCLDir / PluginName.first);
    LoadedPlugins.push_back(std::make_tuple(
        std::move(PluginName.first), std::move(PluginName.second), Library));
  }
 
  return LoadedPlugins;
}
 
} // namespace pi
} // namespace detail
} // namespace _V1
} // namespace sycl