liblttsessiondcomm/liblttsessiondcomm.c

   1 /*
   2  * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <limits.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/socket.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <sys/un.h>
  28 #include <unistd.h>
  29
  30 #include "liblttsessiondcomm.h"
  31
  32 /*
  33  * Human readable error message.
  34  */
  35 static const char *lttcomm_readable_code[] = {
  36         [ LTTCOMM_ERR_INDEX(LTTCOMM_OK) ] = "Success",
  37         [ LTTCOMM_ERR_INDEX(LTTCOMM_ERR) ] = "Unknown error",
  38         [ LTTCOMM_ERR_INDEX(LTTCOMM_UND) ] = "Undefined command",
  39         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESSION) ] = "No session found",
  40         [ LTTCOMM_ERR_INDEX(LTTCOMM_LIST_FAIL) ] = "Unable to list traceable apps",
  41         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_APPS) ] = "No traceable apps found",
  42         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESS) ] = "No session found",
  43 };
  44
  45 /*
  46  *  lttcom_get_readable_code
  47  *
  48  *  Return ptr to string representing a human readable
  49  *  error code from the lttcomm_return_code enum.
  50  *
  51  *  These code MUST be negative in other to treat that
  52  *  as an error value.
  53  */
  54 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  55 {
  56         int tmp_code = -code;
  57
  58         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  59                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  60         }
  61
  62         return "Unknown error code";
  63 }
  64
  65 /*
  66  *      lttcomm_connect_unix_sock
  67  *
  68  *      Connect to unix socket using the path name.
  69  */
  70 int lttcomm_connect_unix_sock(const char *pathname)
  71 {
  72         struct sockaddr_un sun;
  73         int fd;
  74         int ret = 1;
  75
  76         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  77         if (fd < 0) {
  78                 perror("socket");
  79                 goto error;
  80         }
  81
  82         memset(&sun, 0, sizeof(sun));
  83         sun.sun_family = AF_UNIX;
  84         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
  85
  86         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
  87         if (ret < 0) {
  88                 perror("connect");
  89                 goto error;
  90         }
  91
  92         return fd;
  93
  94 error:
  95         return -1;
  96 }
  97
  98 /*
  99  *      lttcomm_accept_unix_sock
 100  *
 101  *      Do an accept(2) on the sock and return the
 102  *      new file descriptor. The socket MUST be bind(2) before.
 103  */
 104 int lttcomm_accept_unix_sock(int sock)
 105 {
 106         int new_fd;
 107         struct sockaddr_un sun;
 108         socklen_t len = 0;
 109
 110         /* Blocking call */
 111         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 112         if (new_fd < 0) {
 113                 perror("accept");
 114                 goto error;
 115         }
 116
 117         return new_fd;
 118
 119 error:
 120         return -1;
 121 }
 122
 123 /*
 124  *      lttcomm_create_unix_sock
 125  *
 126  *      Creates a AF_UNIX local socket using pathname
 127  *      bind the socket upon creation and return the fd.
 128  */
 129 int lttcomm_create_unix_sock(const char *pathname)
 130 {
 131         struct sockaddr_un sun;
 132         int fd;
 133         int ret = -1;
 134
 135         /* Create server socket */
 136         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 137                 perror("socket");
 138                 goto error;
 139         }
 140
 141         memset(&sun, 0, sizeof(sun));
 142         sun.sun_family = AF_UNIX;
 143         strncpy(sun.sun_path, pathname, strlen(pathname));
 144
 145         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 146         if (ret < 0) {
 147                 perror("bind");
 148                 goto error;
 149         }
 150
 151         return fd;
 152
 153 error:
 154         return ret;
 155 }
 156
 157 /*
 158  *      lttcomm_listen_unix_sock
 159  *
 160  *      Make the socket listen using MAX_LISTEN.
 161  */
 162 int lttcomm_listen_unix_sock(int sock)
 163 {
 164         int ret;
 165
 166         ret = listen(sock, MAX_LISTEN);
 167         if (ret < 0) {
 168                 perror("listen");
 169         }
 170
 171         return ret;
 172 }
 173
 174 /*
 175  *      lttcomm_recv_unix_sock
 176  *
 177  *  Receive data of size len in put that data into
 178  *  the buf param. Using recvmsg API.
 179  *  Return the size of received data.
 180  */
 181 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 182 {
 183         struct msghdr msg;
 184         struct iovec iov[1];
 185         ssize_t ret = -1;
 186
 187         memset(&msg, 0, sizeof(msg));
 188
 189         iov[0].iov_base = buf;
 190         iov[0].iov_len = len;
 191         msg.msg_iov = iov;
 192         msg.msg_iovlen = 1;
 193
 194         ret = recvmsg(sock, &msg, 0);
 195         if (ret < 0) {
 196                 perror("recvmsg");
 197         }
 198
 199         return ret;
 200 }
 201
 202 /*
 203  *      lttcomm_send_unix_sock
 204  *
 205  *      Send buf data of size len. Using sendmsg API.
 206  *      Return the size of sent data.
 207  */
 208 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 209 {
 210         struct msghdr msg;
 211         struct iovec iov[1];
 212         ssize_t ret = -1;
 213
 214         memset(&msg, 0, sizeof(msg));
 215
 216         iov[0].iov_base = buf;
 217         iov[0].iov_len = len;
 218         msg.msg_iov = iov;
 219         msg.msg_iovlen = 1;
 220
 221         ret = sendmsg(sock, &msg, 0);
 222         if (ret < 0) {
 223                 perror("sendmsg");
 224         }
 225
 226         return ret;
 227 }