diff options
Diffstat (limited to 'sysdeps/generic/strncpy.c')
-rw-r--r-- | sysdeps/generic/strncpy.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/sysdeps/generic/strncpy.c b/sysdeps/generic/strncpy.c new file mode 100644 index 0000000000..460e0baca4 --- /dev/null +++ b/sysdeps/generic/strncpy.c @@ -0,0 +1,82 @@ +/* Copyright (C) 1991 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <ansidecl.h> +#include <string.h> +#include <memcopy.h> + +char * +DEFUN(strncpy, (s1, s2, n), char *s1 AND CONST char *s2 AND size_t n) +{ + reg_char c; + char *s = s1; + + --s1; + + if (n >= 4) + { + size_t n4 = n >> 2; + + for (;;) + { + c = *s2++; + *++s1 = c; + if (c == '\0') + break; + c = *s2++; + *++s1 = c; + if (c == '\0') + break; + c = *s2++; + *++s1 = c; + if (c == '\0') + break; + c = *s2++; + *++s1 = c; + if (c == '\0') + break; + if (--n4 == 0) + goto last_chars; + } + n = n - (s1 - s) - 1; + if (n == 0) + return s; + goto zero_fill; + } + + last_chars: + n &= 3; + if (n == 0) + return s; + + do + { + c = *s2++; + *++s1 = c; + if (--n == 0) + return s; + } + while (c != '\0'); + + zero_fill: + do + *++s1 = '\0'; + while (--n > 0); + + return s; +} |