lib/crtdll/mbstring/mbsncpy.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS system libraries
   4  * FILE:        lib/crtdll/mbstring/mbsncpy.c
   5  * PURPOSE:     Copies a string to a maximum of n bytes or characters
   6  * PROGRAMER:   Boudewijn Dekker
   7  * UPDATE HISTORY:
   8  *              12/04/99: Created
   9  */
  10
  11 #include <msvcrt/mbstring.h>
  12
  13
  14 unsigned char *_mbsncpy(unsigned char *str1, const unsigned char *str2, size_t n)
  15 {
  16         unsigned char *s1 = (unsigned char *)str1;
  17         unsigned char *s2 = (unsigned char *)str2;
  18
  19         unsigned short *short_s1, *short_s2;
  20
  21         if (n == 0)
  22                 return 0;
  23         do {
  24
  25                 if (*s2 == 0)
  26                         break;
  27
  28                 if (  !_ismbblead(*s2) ) {
  29
  30                         *s1 = *s2;
  31                         s1 += 1;
  32                         s2 += 1;
  33                         n--;
  34                 }
  35                 else {
  36                         short_s1 = (unsigned short *)s1;
  37                         short_s2 = (unsigned short *)s2;
  38                         *short_s1 = *short_s2;
  39                         s1 += 2;
  40                         s2 += 2;
  41                         n--;
  42                 }
  43         } while (n > 0);
  44         return str1;
  45 }
  46
  47
  48 //
  49 //The _mbsnbcpy function copies count bytes from src to dest. If src is shorter
  50 //than dest, the string is padded with null characters. If dest is less than or
  51 //equal to count it is not terminated with a null character.
  52 //
  53
  54 unsigned char * _mbsnbcpy(unsigned char *str1, const unsigned char *str2, size_t n)
  55 {
  56         unsigned char *s1 = (unsigned char *)str1;
  57         unsigned char *s2 = (unsigned char *)str2;
  58
  59         unsigned short *short_s1, *short_s2;
  60
  61         if (n == 0)
  62                 return 0;
  63         do {
  64
  65         if (*s2 == 0) {
  66                         *s1 = *s2;
  67                         break;
  68         }
  69
  70                 if (  !_ismbblead(*s2) ) {
  71
  72                         *s1 = *s2;
  73                         s1 += 1;
  74                         s2 += 1;
  75                         n--;
  76                 }
  77                 else {
  78                         short_s1 = (unsigned short *)s1;
  79                         short_s2 = (unsigned short *)s2;
  80                         *short_s1 = *short_s2;
  81                         s1 += 2;
  82                         s2 += 2;
  83                         n-=2;
  84                 }
  85         } while (n > 0);
  86         return str1;
  87 }