cScm Configuration Daemon

     5         kx 
     5         kx #ifdef HAVE_CONFIG_H
     5         kx #include <config.h>
     5         kx #endif
     5         kx 
     5         kx #include <stdlib.h>
     5         kx #include <stdio.h>
     5         kx #include <unistd.h>
     5         kx #include <string.h>
     5         kx #include <stdarg.h>
     5         kx #include <limits.h>
     5         kx #include <locale.h>
     5         kx #include <wchar.h>
     5         kx #include <wctype.h>
     5         kx 
     5         kx #include <defs.h>
     5         kx #include <utf8ing.h>
     5         kx 
     5         kx 
     5         kx static const ucs4_t replacement_char     = 0xfffd;
     5         kx static const ucs4_t maximum_ucs4         = 0x7fffffff;
     5         kx 
     5         kx static const int    half_shift           = 10;
     5         kx static const ucs4_t half_base            = 0x0010000;
     5         kx 
     5         kx static const ucs4_t surrogate_high_start = 0xd800;
     5         kx static const ucs4_t surrogate_high_end   = 0xdbff;
     5         kx static const ucs4_t surrogate_low_start  = 0xdc00;
     5         kx static const ucs4_t surrogate_low_end    = 0xdfff;
     5         kx 
     5         kx static utf8_t
     5         kx first_byte_mark[7] = { 0x00, 0x00, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc };
     5         kx 
     5         kx 
     5         kx /***************************************************************
     5         kx   static copy_ucs4_to_utf8()
     5         kx 
     5         kx      Переводит строку символов UCS4( src ) в UTF8( dest ).
     5         kx 
     5         kx      Возвращаемое значение:
     5         kx         Количество байт, реально записанное в DEST.
     5         kx 
     5         kx      NOTE:
     5         kx         Выход за пределы памяти, выделенной под указатель DEST
     5         kx         не контролируются.
     5         kx         Подразумевается, что строка SRC имеет null-терминатор.
     5         kx  ***************************************************************/
     5         kx int copy_ucs4_to_utf8( utf8_t *dest, const ucs4_t *src )
     5         kx {
     5         kx   utf8_t   target[7];
     5         kx   utf8_t  *ptr;
     5         kx   int      count = 0;
     5         kx 
     5         kx   while( *src )
     5         kx   {
     5         kx     ucs4_t        c;
     5         kx     int           bytes_to_write = 0;
     5         kx     const ucs4_t  byte_mask = 0xbf;
     5         kx     const ucs4_t  byte_mark = 0x80;
     5         kx 
     5         kx     c = *src++;
     5         kx 
     5         kx     if( c >= surrogate_high_start &&
     5         kx         c <= surrogate_high_end   && *src )
     5         kx     {
     5         kx       ucs4_t c2 = *src;
     5         kx 
     5         kx       if( c2 >= surrogate_low_start &&
     5         kx           c2 <= surrogate_low_end      )
     5         kx       {
     5         kx         c = ((c  - surrogate_high_start) << half_shift) +
     5         kx              (c2 - surrogate_low_start) + half_base;
     5         kx         ++src;
     5         kx       }
     5         kx     }
     5         kx 
     5         kx          if( c <          0x80 ) bytes_to_write = 1;
     5         kx     else if( c <         0x800 ) bytes_to_write = 2;
     5         kx     else if( c <       0x10000 ) bytes_to_write = 3;
     5         kx     else if( c <      0x200000 ) bytes_to_write = 4;
     5         kx     else if( c <     0x4000000 ) bytes_to_write = 5;
     5         kx     else if( c <= maximum_ucs4 ) bytes_to_write = 6;
     5         kx     else
     5         kx     {
     5         kx       bytes_to_write = 2;   c = replacement_char;
     5         kx     }
     5         kx 
     5         kx     ptr = &target[0] + bytes_to_write;
     5         kx 
     5         kx     switch( bytes_to_write )
     5         kx     {
     5         kx       case 6:
     5         kx         *--ptr = (c | byte_mark) & byte_mask; c >>= 6;
     5         kx       case 5:
     5         kx         *--ptr = (c | byte_mark) & byte_mask; c >>= 6;
     5         kx       case 4:
     5         kx         *--ptr = (c | byte_mark) & byte_mask; c >>= 6;
     5         kx       case 3:
     5         kx         *--ptr = (c | byte_mark) & byte_mask; c >>= 6;
     5         kx       case 2:
     5         kx         *--ptr = (c | byte_mark) & byte_mask; c >>= 6;
     5         kx       case 1:
     5         kx         *--ptr = c | first_byte_mark[bytes_to_write];
     5         kx     }
     5         kx 
     5         kx     ptr = &target[0];
     5         kx 
     5         kx     while( bytes_to_write > 0 )
     5         kx     {
     5         kx       *dest++ = *ptr++; /* write byte */
     5         kx       --bytes_to_write;
     5         kx       ++count;
     5         kx     }
     5         kx 
     5         kx   } /* End while( *src ) */
     5         kx 
     5         kx   *dest = (utf8_t)0; /* null terminator */
     5         kx 
     5         kx   return( count );
     5         kx 
     5         kx } /* End of static copy_ucs4_to_utf8() */