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 // mingw-w64 tends to define it as 0x0502 in its headers.
23 #undef _WIN32_WINNT
24 #undef _WIN32_IE
25 
26 // Require at least Windows XP(5.1) API.
27 #define _WIN32_WINNT 0x0501
28 #define _WIN32_IE    0x0600 // MinGW at it again.
29 #define WIN32_LEAN_AND_MEAN
30 
31 #include "llvm/ADT/SmallVector.h"
32 #include "llvm/ADT/StringRef.h"
33 #include "llvm/ADT/Twine.h"
34 #include "llvm/Config/config.h" // Get build system configuration settings
35 #include "llvm/Support/Compiler.h"
36 #include <system_error>
37 #include <windows.h>
38 #include <wincrypt.h>
39 #include <cassert>
40 #include <string>
41 #include <vector>
42 
43 inline bool MakeErrMsg(std::string* ErrMsg, const std::string& prefix) {
44   if (!ErrMsg)
45     return true;
46   char *buffer = NULL;
47   DWORD R = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
48                           FORMAT_MESSAGE_FROM_SYSTEM,
49                           NULL, GetLastError(), 0, (LPSTR)&buffer, 1, NULL);
50   if (R)
51     *ErrMsg = prefix + buffer;
52   else
53     *ErrMsg = prefix + "Unknown error";
54 
55   LocalFree(buffer);
56   return R != 0;
57 }
58 
59 template <typename HandleTraits>
60 class ScopedHandle {
61   typedef typename HandleTraits::handle_type handle_type;
62   handle_type Handle;
63 
64   ScopedHandle(const ScopedHandle &other); // = delete;
65   void operator=(const ScopedHandle &other); // = delete;
66 public:
67   ScopedHandle()
68     : Handle(HandleTraits::GetInvalid()) {}
69 
70   explicit ScopedHandle(handle_type h)
71     : Handle(h) {}
72 
73   ~ScopedHandle() {
74     if (HandleTraits::IsValid(Handle))
75       HandleTraits::Close(Handle);
76   }
77 
78   handle_type take() {
79     handle_type t = Handle;
80     Handle = HandleTraits::GetInvalid();
81     return t;
82   }
83 
84   ScopedHandle &operator=(handle_type h) {
85     if (HandleTraits::IsValid(Handle))
86       HandleTraits::Close(Handle);
87     Handle = h;
88     return *this;
89   }
90 
91   // True if Handle is valid.
92   LLVM_EXPLICIT operator bool() const {
93     return HandleTraits::IsValid(Handle) ? true : false;
94   }
95 
96   operator handle_type() const {
97     return Handle;
98   }
99 };
100 
101 struct CommonHandleTraits {
102   typedef HANDLE handle_type;
103 
104   static handle_type GetInvalid() {
105     return INVALID_HANDLE_VALUE;
106   }
107 
108   static void Close(handle_type h) {
109     ::CloseHandle(h);
110   }
111 
112   static bool IsValid(handle_type h) {
113     return h != GetInvalid();
114   }
115 };
116 
117 struct JobHandleTraits : CommonHandleTraits {
118   static handle_type GetInvalid() {
119     return NULL;
120   }
121 };
122 
123 struct CryptContextTraits : CommonHandleTraits {
124   typedef HCRYPTPROV handle_type;
125 
126   static handle_type GetInvalid() {
127     return 0;
128   }
129 
130   static void Close(handle_type h) {
131     ::CryptReleaseContext(h, 0);
132   }
133 
134   static bool IsValid(handle_type h) {
135     return h != GetInvalid();
136   }
137 };
138 
139 struct FindHandleTraits : CommonHandleTraits {
140   static void Close(handle_type h) {
141     ::FindClose(h);
142   }
143 };
144 
145 struct FileHandleTraits : CommonHandleTraits {};
146 
147 typedef ScopedHandle<CommonHandleTraits> ScopedCommonHandle;
148 typedef ScopedHandle<FileHandleTraits>   ScopedFileHandle;
149 typedef ScopedHandle<CryptContextTraits> ScopedCryptContext;
150 typedef ScopedHandle<FindHandleTraits>   ScopedFindHandle;
151 typedef ScopedHandle<JobHandleTraits>    ScopedJobHandle;
152 
153 namespace llvm {
154 template <class T>
155 class SmallVectorImpl;
156 
157 template <class T>
158 typename SmallVectorImpl<T>::const_pointer
159 c_str(SmallVectorImpl<T> &str) {
160   str.push_back(0);
161   str.pop_back();
162   return str.data();
163 }
164 
165 namespace sys {
166 namespace path {
167 std::error_code widenPath(const Twine &Path8,
168                           SmallVectorImpl<wchar_t> &Path16);
169 } // end namespace path
170 
171 namespace windows {
172 std::error_code UTF8ToUTF16(StringRef utf8, SmallVectorImpl<wchar_t> &utf16);
173 std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
174                             SmallVectorImpl<char> &utf8);
175 /// Convert from UTF16 to the current code page used in the system
176 std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,
177                              SmallVectorImpl<char> &utf8);
178 } // end namespace windows
179 } // end namespace sys
180 } // end namespace llvm.
181