git.sesse.net Git - ccbs/blob - bigscreen/widestring.cpp

   1 #include <stdlib.h>
   2 #include <cstring>
   3 #include <iconv.h>
   4 #include <endian.h>
   5 #include <exception>
   6 #include <pqxx/util>
   7 #include "widestring.h"
   8
   9 static iconv_t ucs4_iconv, ucs4_reverse_iconv;
  10 static bool iconv_initialized = false;
  11
  12 void ensure_iconv_initialized()
  13 {
  14         if (iconv_initialized) {
  15                 return;
  16         }
  17 #if __BYTE_ORDER == __LITTLE_ENDIAN
  18         ucs4_iconv = iconv_open("ucs-4le", "utf-8");
  19         ucs4_reverse_iconv = iconv_open("utf-8", "ucs-4le");
  20 #else
  21         ucs4_iconv = iconv_open("ucs-4be", "utf-8");
  22         ucs4_reverse_iconv = iconv_open("utf-8", "ucs-4be");
  23 #endif
  24
  25         iconv_initialized = true;
  26 }
  27
  28 widestring::widestring()
  29 {
  30 }
  31
  32 widestring::widestring(const char *from)
  33 {
  34         *this = from;
  35 }
  36
  37 widestring::widestring(const std::string &from)
  38 {
  39         *this = from.c_str();
  40 }
  41
  42 widestring::widestring(const std::wstring &from)
  43         : std::wstring(from)
  44 {
  45 }
  46
  47 void widestring::operator= (const char *from)
  48 {
  49         ensure_iconv_initialized();
  50
  51         unsigned bytes = std::strlen(from);
  52         char *from_buf = strdup(from);
  53         wchar_t *to_buf = new wchar_t[bytes + 1];
  54
  55         char *inptr = from_buf, *outptr = reinterpret_cast<char *> (to_buf);
  56
  57         size_t in_left = bytes;
  58         size_t out_left = bytes * sizeof(wchar_t);
  59
  60         size_t ret = iconv(ucs4_iconv, NULL, NULL, &outptr, &out_left);
  61         if (ret == (size_t)(-1)) {
  62                 throw std::runtime_error("Error in iconv during initialization");
  63         }
  64
  65         ret = iconv(ucs4_iconv, &inptr, &in_left, &outptr, &out_left);
  66         if (ret == (size_t)(-1)) {
  67                 perror("iconv");
  68                 throw std::runtime_error("Error in iconv during conversion");
  69         }
  70
  71         erase(begin(), end());
  72         std::copy(to_buf, reinterpret_cast<wchar_t *> (outptr), std::back_inserter(*this));
  73
  74         free(from_buf);
  75         delete[] to_buf;
  76 }
  77
  78 std::string widestring::to_utf8() const
  79 {
  80         ensure_iconv_initialized();
  81
  82         wchar_t *from_buf = wcsdup(c_str());
  83         size_t out_max_size = size() * 6;
  84         char *to_buf = new char[out_max_size];
  85
  86         char *inptr = reinterpret_cast<char *>(from_buf), *outptr = to_buf;
  87
  88         size_t in_left = size() * sizeof(wchar_t);
  89         size_t out_left = out_max_size;
  90
  91         size_t ret = iconv(ucs4_reverse_iconv, NULL, NULL, &outptr, &out_left);
  92         if (ret == (size_t)(-1)) {
  93                 throw std::runtime_error("Error in iconv during initialization");
  94         }
  95
  96         ret = iconv(ucs4_reverse_iconv, &inptr, &in_left, &outptr, &out_left);
  97         if (ret == (size_t)(-1)) {
  98                 perror("iconv");
  99                 throw std::runtime_error("Error in iconv during conversion");
 100         }
 101
 102         std::string utf8(to_buf, outptr);
 103
 104         free(from_buf);
 105         delete[] to_buf;
 106
 107         return utf8;
 108 }