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 20 #ifdef HAVE_LIMITS_H 21 # include <limits.h> 22 #endif 23 24 #include "ares.h" 25 #include "ares_private.h" 26 27 #ifndef HAVE_WRITEV 28 ssize_t ares_writev(ares_socket_t s, const struct iovec *iov, int iovcnt) 29 { 30 char *buffer, *bp; 31 int i; 32 size_t bytes = 0; 33 ssize_t result; 34 35 /* Validate iovcnt */ 36 if (iovcnt <= 0) 37 { 38 SET_ERRNO(EINVAL); 39 return (-1); 40 } 41 42 /* Validate and find the sum of the iov_len values in the iov array */ 43 for (i = 0; i < iovcnt; i++) 44 { 45 if (iov[i].iov_len > INT_MAX - bytes) 46 { 47 SET_ERRNO(EINVAL); 48 return (-1); 49 } 50 bytes += iov[i].iov_len; 51 } 52 53 if (bytes == 0) 54 return (0); 55 56 /* Allocate a temporary buffer to hold the data */ 57 buffer = malloc(bytes); 58 if (!buffer) 59 { 60 SET_ERRNO(ENOMEM); 61 return (-1); 62 } 63 64 /* Copy the data into buffer */ 65 for (bp = buffer, i = 0; i < iovcnt; ++i) 66 { 67 memcpy (bp, iov[i].iov_base, iov[i].iov_len); 68 bp += iov[i].iov_len; 69 } 70 71 /* Send buffer contents */ 72 result = swrite(s, buffer, bytes); 73 74 free(buffer); 75 76 return (result); 77 } 78 #endif 79 80
