1 //===- WindowsSupport.h - Common Windows Include File -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines things specific to Windows implementations.  In addition to
11 // providing some helpers for working with win32 APIs, this header wraps
12 // <windows.h> with some portability macros.  Always include WindowsSupport.h
13 // instead of including <windows.h> directly.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 //===----------------------------------------------------------------------===//
18 //=== WARNING: Implementation here must contain only generic Win32 code that
19 //===          is guaranteed to work on *all* Win32 variants.
20 //===----------------------------------------------------------------------===//
21 
22 #ifndef LLVM_SUPPORT_WINDOWSSUPPORT_H
23 #define LLVM_SUPPORT_WINDOWSSUPPORT_H
24 
25 // mingw-w64 tends to define it as 0x0502 in its headers.
26 #undef _WIN32_WINNT
27 #undef _WIN32_IE
28 
29 // Require at least Windows 7 API.
30 #define _WIN32_WINNT 0x0601
31 #define _WIN32_IE    0x0800 // MinGW at it again. FIXME: verify if still needed.
32 #define WIN32_LEAN_AND_MEAN
33 #ifndef NOMINMAX
34 #define NOMINMAX
35 #endif
36 
37 #include "llvm/ADT/SmallVector.h"
38 #include "llvm/ADT/StringExtras.h"
39 #include "llvm/ADT/StringRef.h"
40 #include "llvm/ADT/Twine.h"
41 #include "llvm/Config/config.h" // Get build system configuration settings
42 #include "llvm/Support/Compiler.h"
43 #include <system_error>
44 #include <windows.h>
45 #include <wincrypt.h>
46 #include <cassert>
47 #include <string>
48 #include <vector>
49 
50 /// Determines if the program is running on Windows 8 or newer. This
51 /// reimplements one of the helpers in the Windows 8.1 SDK, which are intended
52 /// to supercede raw calls to GetVersionEx. Old SDKs, Cygwin, and MinGW don't
53 /// yet have VersionHelpers.h, so we have our own helper.
54 inline bool RunningWindows8OrGreater() {
55   // Windows 8 is version 6.2, service pack 0.
56   OSVERSIONINFOEXW osvi = {};
57   osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
58   osvi.dwMajorVersion = 6;
59   osvi.dwMinorVersion = 2;
60   osvi.wServicePackMajor = 0;
61 
62   DWORDLONG Mask = 0;
63   Mask = VerSetConditionMask(Mask, VER_MAJORVERSION, VER_GREATER_EQUAL);
64   Mask = VerSetConditionMask(Mask, VER_MINORVERSION, VER_GREATER_EQUAL);
65   Mask = VerSetConditionMask(Mask, VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL);
66 
67   return VerifyVersionInfoW(&osvi, VER_MAJORVERSION | VER_MINORVERSION |
68                                        VER_SERVICEPACKMAJOR,
69                             Mask) != FALSE;
70 }
71 
72 inline bool MakeErrMsg(std::string* ErrMsg, const std::string& prefix) {
73   if (!ErrMsg)
74     return true;
75   char *buffer = NULL;
76   DWORD LastError = GetLastError();
77   DWORD R = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
78                           FORMAT_MESSAGE_FROM_SYSTEM |
79                           FORMAT_MESSAGE_MAX_WIDTH_MASK,
80                           NULL, LastError, 0, (LPSTR)&buffer, 1, NULL);
81   if (R)
82     *ErrMsg = prefix + ": " + buffer;
83   else
84     *ErrMsg = prefix + ": Unknown error";
85   *ErrMsg += " (0x" + llvm::utohexstr(LastError) + ")";
86 
87   LocalFree(buffer);
88   return R != 0;
89 }
90 
91 template <typename HandleTraits>
92 class ScopedHandle {
93   typedef typename HandleTraits::handle_type handle_type;
94   handle_type Handle;
95 
96   ScopedHandle(const ScopedHandle &other); // = delete;
97   void operator=(const ScopedHandle &other); // = delete;
98 public:
99   ScopedHandle()
100     : Handle(HandleTraits::GetInvalid()) {}
101 
102   explicit ScopedHandle(handle_type h)
103     : Handle(h) {}
104 
105   ~ScopedHandle() {
106     if (HandleTraits::IsValid(Handle))
107       HandleTraits::Close(Handle);
108   }
109 
110   handle_type take() {
111     handle_type t = Handle;
112     Handle = HandleTraits::GetInvalid();
113     return t;
114   }
115 
116   ScopedHandle &operator=(handle_type h) {
117     if (HandleTraits::IsValid(Handle))
118       HandleTraits::Close(Handle);
119     Handle = h;
120     return *this;
121   }
122 
123   // True if Handle is valid.
124   explicit operator bool() const {
125     return HandleTraits::IsValid(Handle) ? true : false;
126   }
127 
128   operator handle_type() const {
129     return Handle;
130   }
131 };
132 
133 struct CommonHandleTraits {
134   typedef HANDLE handle_type;
135 
136   static handle_type GetInvalid() {
137     return INVALID_HANDLE_VALUE;
138   }
139 
140   static void Close(handle_type h) {
141     ::CloseHandle(h);
142   }
143 
144   static bool IsValid(handle_type h) {
145     return h != GetInvalid();
146   }
147 };
148 
149 struct JobHandleTraits : CommonHandleTraits {
150   static handle_type GetInvalid() {
151     return NULL;
152   }
153 };
154 
155 struct CryptContextTraits : CommonHandleTraits {
156   typedef HCRYPTPROV handle_type;
157 
158   static handle_type GetInvalid() {
159     return 0;
160   }
161 
162   static void Close(handle_type h) {
163     ::CryptReleaseContext(h, 0);
164   }
165 
166   static bool IsValid(handle_type h) {
167     return h != GetInvalid();
168   }
169 };
170 
171 struct FindHandleTraits : CommonHandleTraits {
172   static void Close(handle_type h) {
173     ::FindClose(h);
174   }
175 };
176 
177 struct FileHandleTraits : CommonHandleTraits {};
178 
179 typedef ScopedHandle<CommonHandleTraits> ScopedCommonHandle;
180 typedef ScopedHandle<FileHandleTraits>   ScopedFileHandle;
181 typedef ScopedHandle<CryptContextTraits> ScopedCryptContext;
182 typedef ScopedHandle<FindHandleTraits>   ScopedFindHandle;
183 typedef ScopedHandle<JobHandleTraits>    ScopedJobHandle;
184 
185 namespace llvm {
186 template <class T>
187 class SmallVectorImpl;
188 
189 template <class T>
190 typename SmallVectorImpl<T>::const_pointer
191 c_str(SmallVectorImpl<T> &str) {
192   str.push_back(0);
193   str.pop_back();
194   return str.data();
195 }
196 
197 namespace sys {
198 namespace path {
199 std::error_code widenPath(const Twine &Path8,
200                           SmallVectorImpl<wchar_t> &Path16);
201 } // end namespace path
202 
203 namespace windows {
204 std::error_code UTF8ToUTF16(StringRef utf8, SmallVectorImpl<wchar_t> &utf16);
205 std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
206                             SmallVectorImpl<char> &utf8);
207 /// Convert from UTF16 to the current code page used in the system
208 std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,
209                              SmallVectorImpl<char> &utf8);
210 } // end namespace windows
211 } // end namespace sys
212 } // end namespace llvm.
213 
214 #endif
215