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 };
  43
  44 /*
  45  *  lttcom_get_readable_code
  46  *
  47  *  Return ptr to string representing a human readable
  48  *  error code from the lttcomm_return_code enum.
  49  *
  50  *  These code MUST be negative in other to treat that
  51  *  as an error value.
  52  */
  53 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  54 {
  55         int tmp_code = -code;
  56
  57         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  58                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  59         }
  60
  61         return "Unknown error code";
  62 }
  63
  64 /*
  65  *      lttcomm_connect_unix_sock
  66  *
  67  *      Connect to unix socket using the path name.
  68  */
  69 int lttcomm_connect_unix_sock(const char *pathname)
  70 {
  71         struct sockaddr_un sun;
  72         int fd;
  73         int ret = 1;
  74
  75         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  76         if (fd < 0) {
  77                 perror("socket");
  78                 goto error;
  79         }
  80
  81         memset(&sun, 0, sizeof(sun));
  82         sun.sun_family = AF_UNIX;
  83         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
  84
  85         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
  86         if (ret < 0) {
  87                 perror("connect");
  88                 goto error;
  89         }
  90
  91         return fd;
  92
  93 error:
  94         return -1;
  95 }
  96
  97 /*
  98  *      lttcomm_accept_unix_sock
  99  *
 100  *      Do an accept(2) on the sock and return the
 101  *      new file descriptor. The socket MUST be bind(2) before.
 102  */
 103 int lttcomm_accept_unix_sock(int sock)
 104 {
 105         int new_fd;
 106         struct sockaddr_un sun;
 107         socklen_t len = 0;
 108
 109         /* Blocking call */
 110         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 111         if (new_fd < 0) {
 112                 perror("accept");
 113                 goto error;
 114         }
 115
 116         return new_fd;
 117
 118 error:
 119         return -1;
 120 }
 121
 122 /*
 123  *      lttcomm_create_unix_sock
 124  *
 125  *      Creates a AF_UNIX local socket using pathname
 126  *      bind the socket upon creation and return the fd.
 127  */
 128 int lttcomm_create_unix_sock(const char *pathname)
 129 {
 130         struct sockaddr_un sun;
 131         int fd;
 132         int ret = -1;
 133
 134         /* Create server socket */
 135         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 136                 perror("socket");
 137                 goto error;
 138         }
 139
 140         memset(&sun, 0, sizeof(sun));
 141         sun.sun_family = AF_UNIX;
 142         strncpy(sun.sun_path, pathname, strlen(pathname));
 143
 144         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 145         if (ret < 0) {
 146                 perror("bind");
 147                 goto error;
 148         }
 149
 150         return fd;
 151
 152 error:
 153         return ret;
 154 }
 155
 156 /*
 157  *      lttcomm_listen_unix_sock
 158  *
 159  *      Make the socket listen using MAX_LISTEN.
 160  */
 161 int lttcomm_listen_unix_sock(int sock)
 162 {
 163         int ret;
 164
 165         ret = listen(sock, MAX_LISTEN);
 166         if (ret < 0) {
 167                 perror("listen");
 168         }
 169
 170         return ret;
 171 }
 172
 173 /*
 174  *      lttcomm_recv_unix_sock
 175  *
 176  *  Receive data of size len in put that data into
 177  *  the buf param. Using recvmsg API.
 178  *  Return the size of received data.
 179  */
 180 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 181 {
 182         struct msghdr msg;
 183         struct iovec iov[1];
 184         ssize_t ret = -1;
 185
 186         memset(&msg, 0, sizeof(msg));
 187
 188         iov[0].iov_base = buf;
 189         iov[0].iov_len = len;
 190         msg.msg_iov = iov;
 191         msg.msg_iovlen = 1;
 192
 193         ret = recvmsg(sock, &msg, 0);
 194         if (ret < 0) {
 195                 perror("recvmsg");
 196         }
 197
 198         return ret;
 199 }
 200
 201 /*
 202  *      lttcomm_send_unix_sock
 203  *
 204  *      Send buf data of size len. Using sendmsg API.
 205  *      Return the size of sent data.
 206  */
 207 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 208 {
 209         struct msghdr msg;
 210         struct iovec iov[1];
 211         ssize_t ret = -1;
 212
 213         memset(&msg, 0, sizeof(msg));
 214
 215         iov[0].iov_base = buf;
 216         iov[0].iov_len = len;
 217         msg.msg_iov = iov;
 218         msg.msg_iovlen = 1;
 219
 220         ret = sendmsg(sock, &msg, 0);
 221         if (ret < 0) {
 222                 perror("sendmsg");
 223         }
 224
 225         return ret;
 226 }