Jake Petroules f77a636a01 Switch to a safer technique for obtaining the working directory on Windows
Instead of looping 8 times to work around the TOCTOU issue with sizing the current directory buffer, instead keep doubling the buffer up until the 32767 character limit until the result fits. This ensures we always get a working directory if GetWorkingDirectoryW didn't return some other error, rather than returning nil in the case of a race condition.
2025-05-02 11:29:49 -07:00

326 lines
8.3 KiB
Swift

//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2022 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
//
//===----------------------------------------------------------------------===//
#if os(Windows)
import WinSDK
package var COPY_FILE_FAIL_IF_EXISTS: DWORD {
DWORD(WinSDK.COPY_FILE_FAIL_IF_EXISTS)
}
package var COPY_FILE_COPY_SYMLINK: DWORD {
DWORD(WinSDK.COPY_FILE_COPY_SYMLINK)
}
package var COPY_FILE_NO_BUFFERING: DWORD {
DWORD(WinSDK.COPY_FILE_NO_BUFFERING)
}
package var COPY_FILE_OPEN_AND_COPY_REPARSE_POINT: DWORD {
DWORD(WinSDK.COPY_FILE_OPEN_AND_COPY_REPARSE_POINT)
}
package var COPY_FILE_DIRECTORY: DWORD {
DWORD(WinSDK.COPY_FILE_DIRECTORY)
}
package var CREATE_ALWAYS: DWORD {
DWORD(WinSDK.CREATE_ALWAYS)
}
package var CREATE_NEW: DWORD {
DWORD(WinSDK.CREATE_NEW)
}
package var ERROR_ACCESS_DENIED: DWORD {
DWORD(WinSDK.ERROR_ACCESS_DENIED)
}
package var ERROR_ALREADY_EXISTS: DWORD {
DWORD(WinSDK.ERROR_ALREADY_EXISTS)
}
package var ERROR_BAD_ARGUMENTS: DWORD {
DWORD(WinSDK.ERROR_BAD_ARGUMENTS)
}
package var ERROR_BAD_PATHNAME: DWORD {
DWORD(WinSDK.ERROR_BAD_PATHNAME)
}
package var ERROR_DIRECTORY: DWORD {
DWORD(WinSDK.ERROR_DIRECTORY)
}
package var ERROR_DISK_FULL: DWORD {
DWORD(WinSDK.ERROR_DISK_FULL)
}
package var ERROR_DISK_RESOURCES_EXHAUSTED: DWORD {
DWORD(WinSDK.ERROR_DISK_RESOURCES_EXHAUSTED)
}
package var ERROR_FILE_EXISTS: DWORD {
DWORD(WinSDK.ERROR_FILE_EXISTS)
}
package var ERROR_FILE_NOT_FOUND: DWORD {
DWORD(WinSDK.ERROR_FILE_NOT_FOUND)
}
package var ERROR_FILENAME_EXCED_RANGE: DWORD {
DWORD(WinSDK.ERROR_FILENAME_EXCED_RANGE)
}
package var ERROR_INSUFFICIENT_BUFFER: DWORD {
DWORD(WinSDK.ERROR_INSUFFICIENT_BUFFER)
}
package var ERROR_INVALID_ACCESS: DWORD {
DWORD(WinSDK.ERROR_INVALID_ACCESS)
}
package var ERROR_INVALID_DATA: DWORD {
DWORD(WinSDK.ERROR_INVALID_DATA)
}
package var ERROR_INVALID_DRIVE: DWORD {
DWORD(WinSDK.ERROR_INVALID_DRIVE)
}
package var ERROR_INVALID_NAME: DWORD {
DWORD(WinSDK.ERROR_INVALID_NAME)
}
package var ERROR_LABEL_TOO_LONG: DWORD {
DWORD(WinSDK.ERROR_LABEL_TOO_LONG)
}
package var ERROR_PATH_NOT_FOUND: DWORD {
DWORD(WinSDK.ERROR_PATH_NOT_FOUND)
}
package var ERROR_SHARING_VIOLATION: DWORD {
DWORD(WinSDK.ERROR_SHARING_VIOLATION)
}
package var ERROR_SUCCESS: DWORD {
DWORD(WinSDK.ERROR_SUCCESS)
}
package var ERROR_WRITE_FAULT: DWORD {
DWORD(WinSDK.ERROR_WRITE_FAULT)
}
package var FILE_ATTRIBUTE_DIRECTORY: DWORD {
DWORD(WinSDK.FILE_ATTRIBUTE_DIRECTORY)
}
package var FILE_ATTRIBUTE_NORMAL: DWORD {
DWORD(WinSDK.FILE_ATTRIBUTE_NORMAL)
}
package var FILE_ATTRIBUTE_READONLY: DWORD {
DWORD(WinSDK.FILE_ATTRIBUTE_READONLY)
}
package var FILE_ATTRIBUTE_REPARSE_POINT: DWORD {
DWORD(WinSDK.FILE_ATTRIBUTE_REPARSE_POINT)
}
package var FILE_FLAG_BACKUP_SEMANTICS: DWORD {
DWORD(WinSDK.FILE_FLAG_BACKUP_SEMANTICS)
}
package var FILE_FLAG_OPEN_REPARSE_POINT: DWORD {
DWORD(WinSDK.FILE_FLAG_OPEN_REPARSE_POINT)
}
package var FILE_MAP_READ: DWORD {
DWORD(WinSDK.FILE_MAP_READ)
}
package var FILE_NAME_NORMALIZED: DWORD {
DWORD(WinSDK.FILE_NAME_NORMALIZED)
}
package var FILE_SHARE_DELETE: DWORD {
DWORD(WinSDK.FILE_SHARE_DELETE)
}
package var FILE_SHARE_READ: DWORD {
DWORD(WinSDK.FILE_SHARE_READ)
}
package var FILE_SHARE_WRITE: DWORD {
DWORD(WinSDK.FILE_SHARE_WRITE)
}
package var FILE_TYPE_CHAR: DWORD {
DWORD(WinSDK.FILE_TYPE_CHAR)
}
package var FILE_TYPE_DISK: DWORD {
DWORD(WinSDK.FILE_TYPE_DISK)
}
package var FILE_TYPE_PIPE: DWORD {
DWORD(WinSDK.FILE_TYPE_PIPE)
}
package var FILE_TYPE_UNKNOWN: DWORD {
DWORD(WinSDK.FILE_TYPE_UNKNOWN)
}
package var FIND_FIRST_EX_LARGE_FETCH: DWORD {
DWORD(WinSDK.FIND_FIRST_EX_LARGE_FETCH)
}
package var FIND_FIRST_EX_ON_DISK_ENTRIES_ONLY: DWORD {
DWORD(WinSDK.FIND_FIRST_EX_ON_DISK_ENTRIES_ONLY)
}
package var GENERIC_READ: DWORD {
DWORD(WinSDK.GENERIC_READ)
}
package var GENERIC_WRITE: DWORD {
DWORD(WinSDK.GENERIC_WRITE)
}
package var KF_FLAG_DEFAULT: DWORD {
DWORD(WinSDK.KF_FLAG_DEFAULT.rawValue)
}
package var MOVEFILE_COPY_ALLOWED: DWORD {
DWORD(WinSDK.MOVEFILE_COPY_ALLOWED)
}
package var MOVEFILE_REPLACE_EXISTING: DWORD {
DWORD(WinSDK.MOVEFILE_REPLACE_EXISTING)
}
package var MOVEFILE_WRITE_THROUGH: DWORD {
DWORD(WinSDK.MOVEFILE_WRITE_THROUGH)
}
package var OPEN_ALWAYS: DWORD {
DWORD(WinSDK.OPEN_ALWAYS)
}
package var OPEN_EXISTING: DWORD {
DWORD(WinSDK.OPEN_EXISTING)
}
package var PAGE_READONLY: DWORD {
DWORD(WinSDK.PAGE_READONLY)
}
package var PATHCCH_ALLOW_LONG_PATHS: ULONG {
ULONG(WinSDK.PATHCCH_ALLOW_LONG_PATHS.rawValue)
}
package var RRF_RT_REG_SZ: DWORD {
DWORD(WinSDK.RRF_RT_REG_SZ)
}
package var SHGFI_EXETYPE: UINT {
UINT(WinSDK.SHGFI_EXETYPE)
}
package var SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE: DWORD {
DWORD(WinSDK.SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE)
}
package var SYMBOLIC_LINK_FLAG_DIRECTORY: DWORD {
DWORD(WinSDK.SYMBOLIC_LINK_FLAG_DIRECTORY)
}
package var TOKEN_QUERY: DWORD {
DWORD(WinSDK.TOKEN_QUERY)
}
package var VOLUME_NAME_DOS: DWORD {
DWORD(WinSDK.VOLUME_NAME_DOS)
}
package func PathAllocCombine(_ pszPathIn: String, _ pszMore: String, _ dwFlags: ULONG, _ ppszPathOut: UnsafeMutablePointer<PWSTR?>?) -> HRESULT {
pszPathIn.withCString(encodedAs: UTF16.self) { pszPathIn in
pszMore.withCString(encodedAs: UTF16.self) { pszMore in
WinSDK.PathAllocCombine(pszPathIn, pszMore, dwFlags, ppszPathOut)
}
}
}
@inline(__always)
package func FAILED(_ hr: HRESULT) -> Bool {
hr < 0
}
@inline(__always)
package func HRESULT_CODE(_ hr: HRESULT) -> DWORD {
DWORD(hr) & 0xffff
}
@inline(__always)
package func HRESULT_FACILITY(_ hr: HRESULT) -> DWORD {
DWORD(hr << 16) & 0x1fff
}
@inline(__always)
package func SUCCEEDED(_ hr: HRESULT) -> Bool {
hr >= 0
}
// This is a non-standard extension to the Windows SDK that allows us to convert
// an HRESULT to a Win32 error code.
@inline(__always)
internal func WIN32_FROM_HRESULT(_ hr: HRESULT) -> DWORD {
if SUCCEEDED(hr) { return ERROR_SUCCESS }
if HRESULT_FACILITY(hr) == FACILITY_WIN32 {
return HRESULT_CODE(hr)
}
return DWORD(hr)
}
/// Calls a Win32 API function that fills a (potentially long path) null-terminated string buffer by continually attempting to allocate more memory up until the true max path is reached.
/// This is especially useful for protecting against race conditions like with GetCurrentDirectoryW where the measured length may no longer be valid on subsequent calls.
/// - parameter initialSize: Initial size of the buffer (including the null terminator) to allocate to hold the returned string.
/// - parameter maxSize: Maximum size of the buffer (including the null terminator) to allocate to hold the returned string.
/// - parameter body: Closure to call the Win32 API function to populate the provided buffer.
/// Should return the number of UTF-16 code units (not including the null terminator) copied, 0 to indicate an error.
/// If the buffer is not of sufficient size, should return a value greater than or equal to the size of the buffer.
internal func FillNullTerminatedWideStringBuffer(initialSize: DWORD, maxSize: DWORD, _ body: (UnsafeMutableBufferPointer<WCHAR>) throws -> DWORD) throws -> String {
var bufferCount = max(1, min(initialSize, maxSize))
while bufferCount <= maxSize {
if let result = try withUnsafeTemporaryAllocation(of: WCHAR.self, capacity: Int(bufferCount), { buffer in
let count = try body(buffer)
switch count {
case 0:
throw Win32Error(GetLastError())
case 1..<DWORD(buffer.count):
let result = String(decodingCString: buffer.baseAddress!, as: UTF16.self)
assert(result.utf16.count == count, "Parsed UTF-16 count \(result.utf16.count) != reported UTF-16 count \(count)")
return result
default:
bufferCount *= 2
return nil
}
}) {
return result
}
}
throw Win32Error(ERROR_INSUFFICIENT_BUFFER)
}
#endif