lib/network.c

   1 /*
   2  * Network library.
   3  * Copyright (C) 1997 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <zebra.h>
  23 #include "log.h"
  24 #include "network.h"
  25 #include "lib_errors.h"
  26
  27 /* Read nbytes from fd and store into ptr. */
  28 int readn(int fd, uint8_t *ptr, int nbytes)
  29 {
  30         int nleft;
  31         int nread;
  32
  33         nleft = nbytes;
  34
  35         while (nleft > 0) {
  36                 nread = read(fd, ptr, nleft);
  37
  38                 if (nread < 0)
  39                         return (nread);
  40                 else if (nread == 0)
  41                         break;
  42
  43                 nleft -= nread;
  44                 ptr += nread;
  45         }
  46
  47         return nbytes - nleft;
  48 }
  49
  50 /* Write nbytes from ptr to fd. */
  51 int writen(int fd, const uint8_t *ptr, int nbytes)
  52 {
  53         int nleft;
  54         int nwritten;
  55
  56         nleft = nbytes;
  57
  58         while (nleft > 0) {
  59                 nwritten = write(fd, ptr, nleft);
  60
  61                 if (nwritten < 0) {
  62                         if (!ERRNO_IO_RETRY(errno))
  63                                 return nwritten;
  64                 }
  65                 if (nwritten == 0)
  66                         return (nwritten);
  67
  68                 nleft -= nwritten;
  69                 ptr += nwritten;
  70         }
  71         return nbytes - nleft;
  72 }
  73
  74 int set_nonblocking(int fd)
  75 {
  76         int flags;
  77
  78         /* According to the Single UNIX Spec, the return value for F_GETFL
  79            should
  80            never be negative. */
  81         flags = fcntl(fd, F_GETFL);
  82         if (flags < 0) {
  83                 flog_err(EC_LIB_SYSTEM_CALL,
  84                          "fcntl(F_GETFL) failed for fd %d: %s", fd,
  85                          safe_strerror(errno));
  86                 return -1;
  87         }
  88         if (fcntl(fd, F_SETFL, (flags | O_NONBLOCK)) < 0) {
  89                 flog_err(EC_LIB_SYSTEM_CALL,
  90                          "fcntl failed setting fd %d non-blocking: %s", fd,
  91                          safe_strerror(errno));
  92                 return -1;
  93         }
  94         return 0;
  95 }
  96
  97 int set_cloexec(int fd)
  98 {
  99         int flags;
 100         flags = fcntl(fd, F_GETFD, 0);
 101         if (flags == -1)
 102                 return -1;
 103
 104         flags |= FD_CLOEXEC;
 105         if (fcntl(fd, F_SETFD, flags) == -1)
 106                 return -1;
 107         return 0;
 108 }
 109
 110 float htonf(float host)
 111 {
 112         uint32_t lu1, lu2;
 113         float convert;
 114
 115         memcpy(&lu1, &host, sizeof(uint32_t));
 116         lu2 = htonl(lu1);
 117         memcpy(&convert, &lu2, sizeof(uint32_t));
 118         return convert;
 119 }
 120
 121 float ntohf(float net)
 122 {
 123         return htonf(net);
 124 }