llvm-project/llvm/lib/Support/Windows/PathV2.inc

129 lines
4.1 KiB
C++

//===- llvm/Support/Win32/PathV2.cpp - Windows Path Impl --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Windows specific implementation of the PathV2 API.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only generic Windows code that
//=== is guaranteed to work on *all* Windows variants.
//===----------------------------------------------------------------------===//
#include "Windows.h"
using namespace llvm;
namespace {
error_code UTF8ToUTF16(const StringRef &utf8,
SmallVectorImpl<wchar_t> &utf16) {
int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
utf8.begin(), utf8.size(),
utf16.begin(), 0);
if (len == 0)
return make_error_code(windows_error(::GetLastError()));
utf16.reserve(len + 1);
utf16.set_size(len);
len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
utf8.begin(), utf8.size(),
utf16.begin(), utf16.size());
if (len == 0)
return make_error_code(windows_error(::GetLastError()));
// Make utf16 null terminated.
utf16.push_back(0);
utf16.pop_back();
return make_error_code(errc::success);
}
}
namespace llvm {
namespace sys {
namespace path {
error_code current_path(SmallVectorImpl<char> &result) {
SmallVector<wchar_t, 128> cur_path;
cur_path.reserve(128);
retry_cur_dir:
DWORD len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
// A zero return value indicates a failure other than insufficient space.
if (len == 0)
return make_error_code(windows_error(::GetLastError()));
// If there's insufficient space, the len returned is larger than the len
// given.
if (len > cur_path.capacity()) {
cur_path.reserve(len);
goto retry_cur_dir;
}
cur_path.set_size(len);
// cur_path now holds the current directory in utf-16. Convert to utf-8.
// Find out how much space we need. Sadly, this function doesn't return the
// size needed unless you tell it the result size is 0, which means you
// _always_ have to call it twice.
len = ::WideCharToMultiByte(CP_UTF8, NULL,
cur_path.data(), cur_path.size(),
result.data(), 0,
NULL, NULL);
if (len == 0)
return make_error_code(windows_error(::GetLastError()));
result.reserve(len);
result.set_size(len);
// Now do the actual conversion.
len = ::WideCharToMultiByte(CP_UTF8, NULL,
cur_path.data(), cur_path.size(),
result.data(), result.size(),
NULL, NULL);
if (len == 0)
return make_error_code(windows_error(::GetLastError()));
return make_error_code(errc::success);
}
} // end namespace path
namespace fs {
error_code copy_file(const Twine &from, const Twine &to, copy_option copt) {
// Get arguments.
SmallString<128> from_storage;
SmallString<128> to_storage;
StringRef f = from.toStringRef(from_storage);
StringRef t = to.toStringRef(to_storage);
// Convert to utf-16.
SmallVector<wchar_t, 128> wide_from;
SmallVector<wchar_t, 128> wide_to;
if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
// Copy the file.
BOOL res = ::CopyFileW(wide_from.begin(), wide_to.begin(),
copt != copy_option::overwrite_if_exists);
if (res == 0)
return make_error_code(windows_error(::GetLastError()));
return make_error_code(errc::success);
}
} // end namespace fs
} // end namespace sys
} // end namespace llvm