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 /*
  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 /*
  53  * The _mbsnbcpy function copies count bytes from src to dest. If src is shorter
  54  * than dest, the string is padded with null characters. If dest is less than or
  55  * equal to count it is not terminated with a null character.
  56  *
  57  * @implemented
  58  */
  59 unsigned char * _mbsnbcpy(unsigned char *str1, const unsigned char *str2, size_t n)
  60 {
  61         unsigned char *s1 = (unsigned char *)str1;
  62         unsigned char *s2 = (unsigned char *)str2;
  63
  64         unsigned short *short_s1, *short_s2;
  65
  66         if (n == 0)
  67                 return 0;
  68         do {
  69
  70         if (*s2 == 0) {
  71                         *s1 = *s2;
  72                         break;
  73         }
  74
  75                 if (  !_ismbblead(*s2) ) {
  76
  77                         *s1 = *s2;
  78                         s1 += 1;
  79                         s2 += 1;
  80                         n--;
  81                 }
  82                 else {
  83                         short_s1 = (unsigned short *)s1;
  84                         short_s2 = (unsigned short *)s2;
  85                         *short_s1 = *short_s2;
  86                         s1 += 2;
  87                         s2 += 2;
  88                         n-=2;
  89                 }
  90         } while (n > 0);
  91         return str1;
  92 }