lib/msvcrt/mbstring/mbsncpy.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS system libraries
   4  * FILE:        lib/msvcrt/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 /*
  15  * @implemented
  16  */
  17 unsigned char* _mbsncpy(unsigned char *str1, const unsigned char *str2, size_t n)
  18 {
  19         unsigned char *s1 = (unsigned char *)str1;
  20         unsigned char *s2 = (unsigned char *)str2;
  21
  22         unsigned short *short_s1, *short_s2;
  23
  24         if (n == 0)
  25                 return 0;
  26         do {
  27
  28                 if (*s2 == 0)
  29                         break;
  30
  31                 if (  !_ismbblead(*s2) ) {
  32
  33                         *s1 = *s2;
  34                         s1 += 1;
  35                         s2 += 1;
  36                         n--;
  37                 }
  38                 else {
  39                         short_s1 = (unsigned short *)s1;
  40                         short_s2 = (unsigned short *)s2;
  41                         *short_s1 = *short_s2;
  42                         s1 += 2;
  43                         s2 += 2;
  44                         n--;
  45                 }
  46         } while (n > 0);
  47         return str1;
  48 }
  49
  50
  51 /*
  52  * The _mbsnbcpy function copies count bytes from src to dest. If src is shorter
  53  * than dest, the string is padded with null characters. If dest is less than or
  54  * equal to count it is not terminated with a null character.
  55  *
  56  * @implemented
  57  */
  58 unsigned char * _mbsnbcpy(unsigned char *str1, const unsigned char *str2, size_t n)
  59 {
  60         unsigned char *s1 = (unsigned char *)str1;
  61         unsigned char *s2 = (unsigned char *)str2;
  62
  63         unsigned short *short_s1, *short_s2;
  64
  65         if (n == 0)
  66                 return 0;
  67         do {
  68
  69         if (*s2 == 0) {
  70                         *s1 = *s2;
  71                         break;
  72         }
  73
  74                 if (  !_ismbblead(*s2) ) {
  75
  76                         *s1 = *s2;
  77                         s1 += 1;
  78                         s2 += 1;
  79                         n--;
  80                 }
  81                 else {
  82                         short_s1 = (unsigned short *)s1;
  83                         short_s2 = (unsigned short *)s2;
  84                         *short_s1 = *short_s2;
  85                         s1 += 2;
  86                         s2 += 2;
  87                         n-=2;
  88                 }
  89         } while (n > 0);
  90         return str1;
  91 }