common/win_main_utf8.h

   1 #ifndef WIN_MAIN_UTF8_H
   2 #define WIN_MAIN_UTF8_H
   3
   4 /* For Windows systems this provides a way to get UTF-8 encoded argv strings,
   5  * and also overrides fopen to accept UTF-8 filenames. Working with wmain
   6  * directly complicates cross-platform compatibility, while normal main() in
   7  * Windows uses the current codepage (which has limited availability of
   8  * characters).
   9  *
  10  * For MinGW, you must link with -municode
  11  */
  12 #ifdef _WIN32
  13 #define WIN32_LEAN_AND_MEAN
  14 #include <windows.h>
  15 #include <shellapi.h>
  16 #include <wchar.h>
  17
  18 #ifdef __cplusplus
  19 #include <memory>
  20
  21 #define STATIC_CAST(...) static_cast<__VA_ARGS__>
  22 #define REINTERPRET_CAST(...) reinterpret_cast<__VA_ARGS__>
  23
  24 #else
  25
  26 #define STATIC_CAST(...) (__VA_ARGS__)
  27 #define REINTERPRET_CAST(...) (__VA_ARGS__)
  28 #endif
  29
  30 static FILE *my_fopen(const char *fname, const char *mode)
  31 {
  32     wchar_t *wname=NULL, *wmode=NULL;
  33     int namelen, modelen;
  34     FILE *file = NULL;
  35     errno_t err;
  36
  37     namelen = MultiByteToWideChar(CP_UTF8, 0, fname, -1, NULL, 0);
  38     modelen = MultiByteToWideChar(CP_UTF8, 0, mode, -1, NULL, 0);
  39
  40     if(namelen <= 0 || modelen <= 0)
  41     {
  42         fprintf(stderr, "Failed to convert UTF-8 fname \"%s\", mode \"%s\"\n", fname, mode);
  43         return NULL;
  44     }
  45
  46 #ifdef __cplusplus
  47     auto strbuf = std::make_unique<wchar_t[]>(static_cast<size_t>(namelen)+modelen);
  48     wname = strbuf.get();
  49 #else
  50     wname = (wchar_t*)calloc(sizeof(wchar_t), (size_t)namelen + modelen);
  51 #endif
  52     wmode = wname + namelen;
  53     MultiByteToWideChar(CP_UTF8, 0, fname, -1, wname, namelen);
  54     MultiByteToWideChar(CP_UTF8, 0, mode, -1, wmode, modelen);
  55
  56     err = _wfopen_s(&file, wname, wmode);
  57     if(err)
  58     {
  59         errno = err;
  60         file = NULL;
  61     }
  62
  63 #ifndef __cplusplus
  64     free(wname);
  65 #endif
  66     return file;
  67 }
  68 #define fopen my_fopen
  69
  70
  71 /* SDL overrides main and provides UTF-8 args for us. */
  72 #if !defined(SDL_MAIN_NEEDED) && !defined(SDL_MAIN_AVAILABLE)
  73 int my_main(int, char**);
  74 #define main my_main
  75
  76 #ifdef __cplusplus
  77 extern "C"
  78 #endif
  79 int wmain(int argc, wchar_t **wargv)
  80 {
  81     char **argv;
  82     size_t total;
  83     int i;
  84
  85     total = sizeof(*argv) * STATIC_CAST(size_t)(argc);
  86     for(i = 0;i < argc;i++)
  87         total += STATIC_CAST(size_t)(WideCharToMultiByte(CP_UTF8, 0, wargv[i], -1, NULL, 0, NULL,
  88             NULL));
  89
  90 #ifdef __cplusplus
  91     auto argbuf = std::make_unique<char[]>(total);
  92     argv = reinterpret_cast<char**>(argbuf.get());
  93 #else
  94     argv = (char**)calloc(1, total);
  95 #endif
  96     argv[0] = REINTERPRET_CAST(char*)(argv + argc);
  97     for(i = 0;i < argc-1;i++)
  98     {
  99         int len = WideCharToMultiByte(CP_UTF8, 0, wargv[i], -1, argv[i], 65535, NULL, NULL);
 100         argv[i+1] = argv[i] + len;
 101     }
 102     WideCharToMultiByte(CP_UTF8, 0, wargv[i], -1, argv[i], 65535, NULL, NULL);
 103
 104 #ifdef __cplusplus
 105     return main(argc, argv);
 106 #else
 107     i = main(argc, argv);
 108
 109     free(argv);
 110     return i;
 111 #endif
 112 }
 113 #endif /* !defined(SDL_MAIN_NEEDED) && !defined(SDL_MAIN_AVAILABLE) */
 114
 115 #endif /* _WIN32 */
 116
 117 #endif /* WIN_MAIN_UTF8_H */