1 2 3 /* Copyright 1998 by the Massachusetts Institute of Technology. 4 * 5 * Permission to use, copy, modify, and distribute this 6 * software and its documentation for any purpose and without 7 * fee is hereby granted, provided that the above copyright 8 * notice appear in all copies and that both that copyright 9 * notice and this permission notice appear in supporting 10 * documentation, and that the name of M.I.T. not be used in 11 * advertising or publicity pertaining to distribution of the 12 * software without specific, written prior permission. 13 * M.I.T. makes no representations about the suitability of 14 * this software for any purpose. It is provided "as is" 15 * without express or implied warranty. 16 */ 17 18 #include "ares_setup.h" 19 #include "ares_strdup.h" 20 21 #ifndef HAVE_STRDUP 22 char *ares_strdup(const char *s1) 23 { 24 size_t sz; 25 char * s2; 26 27 if(s1) { 28 sz = strlen(s1); 29 if(sz < (size_t)-1) { 30 sz++; 31 if(sz < ((size_t)-1) / sizeof(char)) { 32 s2 = malloc(sz * sizeof(char)); 33 if(s2) { 34 memcpy(s2, s1, sz * sizeof(char)); 35 return s2; 36 } 37 } 38 } 39 } 40 return (char *)NULL; 41 } 42 #endif 43
