1 /* Implement the strndup function. 2 Copyright (C) 2005 Free Software Foundation, Inc. 3 Written by Kaveh R. Ghazi <ghazi (at) caip.rutgers.edu>. 4 5 This file is part of the libiberty library. 6 Libiberty is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Library General Public 8 License as published by the Free Software Foundation; either 9 version 2 of the License, or (at your option) any later version. 10 11 Libiberty is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Library General Public License for more details. 15 16 You should have received a copy of the GNU Library General Public 17 License along with libiberty; see the file COPYING.LIB. If 18 not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, 19 Boston, MA 02110-1301, USA. */ 20 21 /* 22 23 @deftypefn Extension char* strndup (const char *@var{s}, size_t @var{n}) 24 25 Returns a pointer to a copy of @var{s} with at most @var{n} characters 26 in memory obtained from @code{malloc}, or @code{NULL} if insufficient 27 memory was available. The result is always NUL terminated. 28 29 @end deftypefn 30 31 */ 32 33 #include "ansidecl.h" 34 #include <stddef.h> 35 36 extern size_t strlen (const char*); 37 extern PTR malloc (size_t); 38 extern PTR memcpy (PTR, const PTR, size_t); 39 40 char * 41 strndup (const char *s, size_t n) 42 { 43 char *result; 44 size_t len = strlen (s); 45 46 if (n < len) 47 len = n; 48 49 result = (char *) malloc (len + 1); 50 if (!result) 51 return 0; 52 53 result[len] = '\0'; 54 return (char *) memcpy (result, s, len); 55 } 56