ctl_socket_client.c

   1 /*****************************************************************************
   2   Copyright (c) 2006 EMC Corporation.
   3
   4   This program is free software; you can redistribute it and/or modify it
   5   under the terms of the GNU General Public License as published by the Free
   6   Software Foundation; either version 2 of the License, or (at your option)
   7   any later version.
   8
   9   This program is distributed in the hope that it will be useful, but WITHOUT
  10   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12   more details.
  13
  14   You should have received a copy of the GNU General Public License along with
  15   this program; if not, write to the Free Software Foundation, Inc., 59
  16   Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17
  18   The full GNU General Public License is included in this distribution in the
  19   file called LICENSE.
  20
  21   Authors: Srinivas Aji <Aji_Srinivas@emc.com>
  22
  23 ******************************************************************************/
  24
  25 #include "ctl_socket.h"
  26 #include <sys/stat.h>
  27 #include <sys/types.h>
  28 #include <sys/socket.h>
  29 #include <sys/un.h>
  30 #include <unistd.h>
  31 #include <sys/poll.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34
  35 #include "log.h"
  36
  37 static int fd = -1;
  38
  39 int ctl_client_init(void)
  40 {
  41         struct sockaddr_un sa_svr;
  42         int s;
  43         TST(strlen(RSTP_SERVER_SOCK_NAME) < sizeof(sa_svr.sun_path), -1);
  44
  45         s = socket(PF_UNIX, SOCK_DGRAM, 0);
  46         if (s < 0) {
  47                 ERROR("Couldn't open unix socket: %m");
  48                 return -1;
  49         }
  50
  51         set_socket_address(&sa_svr, RSTP_SERVER_SOCK_NAME);
  52
  53         struct sockaddr_un sa;
  54         char tmpname[64];
  55         sprintf(tmpname, "RSTPCTL_%d", getpid());
  56         set_socket_address(&sa, tmpname);
  57         /* We need this bind. The autobind on connect isn't working properly.
  58            The server doesn't get a proper sockaddr in recvmsg if we don't do this.
  59          */
  60         if (bind(s, (struct sockaddr *)&sa, sizeof(sa)) != 0) {
  61                 ERROR("Couldn't bind socket: %m");
  62                 close(s);
  63                 return -1;
  64         }
  65
  66         if (connect(s, (struct sockaddr *)&sa_svr, sizeof(sa_svr)) != 0) {
  67                 ERROR("Couldn't connect to server");
  68                 close(s);
  69                 return -1;
  70         }
  71         fd = s;
  72
  73         return 0;
  74 }
  75
  76 void ctl_client_cleanup(void)
  77 {
  78         if (fd >= 0) {
  79                 close(fd);
  80                 fd = -1;
  81         }
  82 }
  83
  84 int send_ctl_message(int cmd, void *inbuf, int lin, void *outbuf, int *lout,
  85                      int *res)
  86 {
  87         struct ctl_msg_hdr mhdr;
  88         struct msghdr msg;
  89         struct iovec iov[2];
  90         int l;
  91
  92         msg.msg_name = NULL;
  93         msg.msg_namelen = 0;
  94         msg.msg_iov = iov;
  95         msg.msg_iovlen = 2;
  96         msg.msg_control = NULL;
  97         msg.msg_controllen = 0;
  98
  99         mhdr.cmd = cmd;
 100         mhdr.lin = lin;
 101         mhdr.lout = lout != NULL ? *lout : 0;
 102         iov[0].iov_base = &mhdr;
 103         iov[0].iov_len = sizeof(mhdr);
 104         iov[1].iov_base = (void *)inbuf;
 105         iov[1].iov_len = lin;
 106
 107         l = sendmsg(fd, &msg, 0);
 108         if (l < 0) {
 109                 ERROR("Error sending message to server: %m");
 110                 return -1;
 111         }
 112         if (l != sizeof(mhdr) + lin) {
 113                 ERROR("Error sending message to server: Partial write");
 114                 return -1;
 115         }
 116
 117         iov[1].iov_base = outbuf;
 118         iov[1].iov_len = lout != NULL ? *lout : 0;
 119
 120         {
 121                 struct pollfd pfd;
 122                 int timeout = 5000;     /* 5 s */
 123                 int r;
 124
 125                 pfd.fd = fd;
 126                 pfd.events = POLLIN;
 127                 do {
 128                         r = poll(&pfd, 1, timeout);
 129                         if (r == 0) {
 130                                 ERROR
 131                                     ("Error getting message from server: Timeout");
 132                                 return -1;
 133                         }
 134                         if (r < 0) {
 135                                 ERROR
 136                                     ("Error getting message from server: poll error: %m");
 137                                 return -1;
 138                         }
 139                 } while ((pfd.
 140                           revents & (POLLERR | POLLHUP | POLLNVAL | POLLIN)) ==
 141                          0);
 142
 143                 l = recvmsg(fd, &msg, 0);
 144                 if (l < 0) {
 145                         ERROR("Error getting message from server: %m");
 146                         return -1;
 147                 }
 148                 if (l < sizeof(mhdr) || l != sizeof(mhdr) + mhdr.lout
 149                     || mhdr.cmd != cmd) {
 150                         ERROR("Error getting message from server: Bad format");
 151                         return -1;
 152                 }
 153         }
 154         if (lout)
 155                 *lout = mhdr.lout;
 156         if (res)
 157                 *res = mhdr.res;
 158
 159         return 0;
 160 }