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
  26 /* Read nbytes from fd and store into ptr. */
  27 int readn(int fd, uint8_t *ptr, int nbytes)
  28 {
  29         int nleft;
  30         int nread;
  31
  32         nleft = nbytes;
  33
  34         while (nleft > 0) {
  35                 nread = read(fd, ptr, nleft);
  36
  37                 if (nread < 0)
  38                         return (nread);
  39                 else if (nread == 0)
  40                         break;
  41
  42                 nleft -= nread;
  43                 ptr += nread;
  44         }
  45
  46         return nbytes - nleft;
  47 }
  48
  49 /* Write nbytes from ptr to fd. */
  50 int writen(int fd, const uint8_t *ptr, int nbytes)
  51 {
  52         int nleft;
  53         int nwritten;
  54
  55         nleft = nbytes;
  56
  57         while (nleft > 0) {
  58                 nwritten = write(fd, ptr, nleft);
  59
  60                 if (nwritten < 0) {
  61                         if (!ERRNO_IO_RETRY(errno))
  62                                 return nwritten;
  63                 }
  64                 if (nwritten == 0)
  65                         return (nwritten);
  66
  67                 nleft -= nwritten;
  68                 ptr += nwritten;
  69         }
  70         return nbytes - nleft;
  71 }
  72
  73 int set_nonblocking(int fd)
  74 {
  75         int flags;
  76
  77         /* According to the Single UNIX Spec, the return value for F_GETFL
  78            should
  79            never be negative. */
  80         if ((flags = fcntl(fd, F_GETFL)) < 0) {
  81                 zlog_warn("fcntl(F_GETFL) failed for fd %d: %s", fd,
  82                           safe_strerror(errno));
  83                 return -1;
  84         }
  85         if (fcntl(fd, F_SETFL, (flags | O_NONBLOCK)) < 0) {
  86                 zlog_warn("fcntl failed setting fd %d non-blocking: %s", fd,
  87                           safe_strerror(errno));
  88                 return -1;
  89         }
  90         return 0;
  91 }
  92
  93 int set_cloexec(int fd)
  94 {
  95         int flags;
  96         flags = fcntl(fd, F_GETFD, 0);
  97         if (flags == -1)
  98                 return -1;
  99
 100         flags |= FD_CLOEXEC;
 101         if (fcntl(fd, F_SETFD, flags) == -1)
 102                 return -1;
 103         return 0;
 104 }
 105
 106 float htonf(float host)
 107 {
 108         uint32_t lu1, lu2;
 109         float convert;
 110
 111         memcpy(&lu1, &host, sizeof(uint32_t));
 112         lu2 = htonl(lu1);
 113         memcpy(&convert, &lu2, sizeof(uint32_t));
 114         return convert;
 115 }
 116
 117 float ntohf(float net)
 118 {
 119         return htonf(net);
 120 }