1 //===- WindowsSupport.h - Common Windows Include File -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines things specific to Windows implementations.  In addition to
10 // providing some helpers for working with win32 APIs, this header wraps
11 // <windows.h> with some portability macros.  Always include WindowsSupport.h
12 // instead of including <windows.h> directly.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 //===----------------------------------------------------------------------===//
17 //=== WARNING: Implementation here must contain only generic Win32 code that
18 //===          is guaranteed to work on *all* Win32 variants.
19 //===----------------------------------------------------------------------===//
20 
21 #ifndef LLVM_SUPPORT_WINDOWSSUPPORT_H
22 #define LLVM_SUPPORT_WINDOWSSUPPORT_H
23 
24 // mingw-w64 tends to define it as 0x0502 in its headers.
25 #undef _WIN32_WINNT
26 #undef _WIN32_IE
27 
28 // Require at least Windows 7 API.
29 #define _WIN32_WINNT 0x0601
30 #define _WIN32_IE    0x0800 // MinGW at it again. FIXME: verify if still needed.
31 #define WIN32_LEAN_AND_MEAN
32 #ifndef NOMINMAX
33 #define NOMINMAX
34 #endif
35 
36 #include "llvm/ADT/SmallVector.h"
37 #include "llvm/ADT/StringExtras.h"
38 #include "llvm/ADT/StringRef.h"
39 #include "llvm/ADT/Twine.h"
40 #include "llvm/Config/llvm-config.h" // Get build system configuration settings
41 #include "llvm/Support/Allocator.h"
42 #include "llvm/Support/Chrono.h"
43 #include "llvm/Support/Compiler.h"
44 #include "llvm/Support/ErrorHandling.h"
45 #include "llvm/Support/VersionTuple.h"
46 #include <cassert>
47 #include <string>
48 #include <system_error>
49 #include <windows.h>
50 
51 // Must be included after windows.h
52 #include <wincrypt.h>
53 
54 namespace llvm {
55 
56 /// Determines if the program is running on Windows 8 or newer. This
57 /// reimplements one of the helpers in the Windows 8.1 SDK, which are intended
58 /// to supercede raw calls to GetVersionEx. Old SDKs, Cygwin, and MinGW don't
59 /// yet have VersionHelpers.h, so we have our own helper.
60 bool RunningWindows8OrGreater();
61 
62 /// Determines if the program is running on Windows 11 or Windows Server 2022.
63 bool RunningWindows11OrGreater();
64 
65 /// Returns the Windows version as Major.Minor.0.BuildNumber. Uses
66 /// RtlGetVersion or GetVersionEx under the hood depending on what is available.
67 /// GetVersionEx is deprecated, but this API exposes the build number which can
68 /// be useful for working around certain kernel bugs.
69 llvm::VersionTuple GetWindowsOSVersion();
70 
71 bool MakeErrMsg(std::string *ErrMsg, const std::string &prefix);
72 
73 // Include GetLastError() in a fatal error message.
ReportLastErrorFatal(const char * Msg)74 [[noreturn]] inline void ReportLastErrorFatal(const char *Msg) {
75   std::string ErrMsg;
76   MakeErrMsg(&ErrMsg, Msg);
77   llvm::report_fatal_error(Twine(ErrMsg));
78 }
79 
80 template <typename HandleTraits>
81 class ScopedHandle {
82   typedef typename HandleTraits::handle_type handle_type;
83   handle_type Handle;
84 
85   ScopedHandle(const ScopedHandle &other) = delete;
86   void operator=(const ScopedHandle &other) = delete;
87 public:
ScopedHandle()88   ScopedHandle()
89     : Handle(HandleTraits::GetInvalid()) {}
90 
ScopedHandle(handle_type h)91   explicit ScopedHandle(handle_type h)
92     : Handle(h) {}
93 
~ScopedHandle()94   ~ScopedHandle() {
95     if (HandleTraits::IsValid(Handle))
96       HandleTraits::Close(Handle);
97   }
98 
take()99   handle_type take() {
100     handle_type t = Handle;
101     Handle = HandleTraits::GetInvalid();
102     return t;
103   }
104 
105   ScopedHandle &operator=(handle_type h) {
106     if (HandleTraits::IsValid(Handle))
107       HandleTraits::Close(Handle);
108     Handle = h;
109     return *this;
110   }
111 
112   // True if Handle is valid.
113   explicit operator bool() const {
114     return HandleTraits::IsValid(Handle) ? true : false;
115   }
116 
handle_type()117   operator handle_type() const {
118     return Handle;
119   }
120 };
121 
122 struct CommonHandleTraits {
123   typedef HANDLE handle_type;
124 
GetInvalidCommonHandleTraits125   static handle_type GetInvalid() {
126     return INVALID_HANDLE_VALUE;
127   }
128 
CloseCommonHandleTraits129   static void Close(handle_type h) {
130     ::CloseHandle(h);
131   }
132 
IsValidCommonHandleTraits133   static bool IsValid(handle_type h) {
134     return h != GetInvalid();
135   }
136 };
137 
138 struct JobHandleTraits : CommonHandleTraits {
GetInvalidJobHandleTraits139   static handle_type GetInvalid() {
140     return NULL;
141   }
142 };
143 
144 struct CryptContextTraits : CommonHandleTraits {
145   typedef HCRYPTPROV handle_type;
146 
GetInvalidCryptContextTraits147   static handle_type GetInvalid() {
148     return 0;
149   }
150 
CloseCryptContextTraits151   static void Close(handle_type h) {
152     ::CryptReleaseContext(h, 0);
153   }
154 
IsValidCryptContextTraits155   static bool IsValid(handle_type h) {
156     return h != GetInvalid();
157   }
158 };
159 
160 struct RegTraits : CommonHandleTraits {
161   typedef HKEY handle_type;
162 
GetInvalidRegTraits163   static handle_type GetInvalid() {
164     return NULL;
165   }
166 
CloseRegTraits167   static void Close(handle_type h) {
168     ::RegCloseKey(h);
169   }
170 
IsValidRegTraits171   static bool IsValid(handle_type h) {
172     return h != GetInvalid();
173   }
174 };
175 
176 struct FindHandleTraits : CommonHandleTraits {
CloseFindHandleTraits177   static void Close(handle_type h) {
178     ::FindClose(h);
179   }
180 };
181 
182 struct FileHandleTraits : CommonHandleTraits {};
183 
184 typedef ScopedHandle<CommonHandleTraits> ScopedCommonHandle;
185 typedef ScopedHandle<FileHandleTraits>   ScopedFileHandle;
186 typedef ScopedHandle<CryptContextTraits> ScopedCryptContext;
187 typedef ScopedHandle<RegTraits>          ScopedRegHandle;
188 typedef ScopedHandle<FindHandleTraits>   ScopedFindHandle;
189 typedef ScopedHandle<JobHandleTraits>    ScopedJobHandle;
190 
191 template <class T>
192 class SmallVectorImpl;
193 
194 template <class T>
195 typename SmallVectorImpl<T>::const_pointer
c_str(SmallVectorImpl<T> & str)196 c_str(SmallVectorImpl<T> &str) {
197   str.push_back(0);
198   str.pop_back();
199   return str.data();
200 }
201 
202 namespace sys {
203 
toDuration(FILETIME Time)204 inline std::chrono::nanoseconds toDuration(FILETIME Time) {
205   ULARGE_INTEGER TimeInteger;
206   TimeInteger.LowPart = Time.dwLowDateTime;
207   TimeInteger.HighPart = Time.dwHighDateTime;
208 
209   // FILETIME's are # of 100 nanosecond ticks (1/10th of a microsecond)
210   return std::chrono::nanoseconds(100 * TimeInteger.QuadPart);
211 }
212 
toTimePoint(FILETIME Time)213 inline TimePoint<> toTimePoint(FILETIME Time) {
214   ULARGE_INTEGER TimeInteger;
215   TimeInteger.LowPart = Time.dwLowDateTime;
216   TimeInteger.HighPart = Time.dwHighDateTime;
217 
218   // Adjust for different epoch
219   TimeInteger.QuadPart -= 11644473600ll * 10000000;
220 
221   // FILETIME's are # of 100 nanosecond ticks (1/10th of a microsecond)
222   return TimePoint<>(std::chrono::nanoseconds(100 * TimeInteger.QuadPart));
223 }
224 
toFILETIME(TimePoint<> TP)225 inline FILETIME toFILETIME(TimePoint<> TP) {
226   ULARGE_INTEGER TimeInteger;
227   TimeInteger.QuadPart = TP.time_since_epoch().count() / 100;
228   TimeInteger.QuadPart += 11644473600ll * 10000000;
229 
230   FILETIME Time;
231   Time.dwLowDateTime = TimeInteger.LowPart;
232   Time.dwHighDateTime = TimeInteger.HighPart;
233   return Time;
234 }
235 
236 namespace windows {
237 // Returns command line arguments. Unlike arguments given to main(),
238 // this function guarantees that the returned arguments are encoded in
239 // UTF-8 regardless of the current code page setting.
240 std::error_code GetCommandLineArguments(SmallVectorImpl<const char *> &Args,
241                                         BumpPtrAllocator &Alloc);
242 
243 /// Convert UTF-8 path to a suitable UTF-16 path for use with the Win32 Unicode
244 /// File API.
245 std::error_code widenPath(const Twine &Path8, SmallVectorImpl<wchar_t> &Path16,
246                           size_t MaxPathLen = MAX_PATH);
247 
248 } // end namespace windows
249 } // end namespace sys
250 } // end namespace llvm.
251 
252 #endif
253