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         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACE) ] = "No trace found",
  44         [ LTTCOMM_ERR_INDEX(LTTCOMM_FATAL) ] = "Fatal error of the session daemon",
  45         [ LTTCOMM_ERR_INDEX(LTTCOMM_CREATE_FAIL) ] = "Create trace failed",
  46         [ LTTCOMM_ERR_INDEX(LTTCOMM_START_FAIL) ] = "Start trace failed",
  47         [ LTTCOMM_ERR_INDEX(LTTCOMM_STOP_FAIL) ] = "Stop trace failed",
  48         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACEABLE) ] = "App is not traceable",
  49         [ LTTCOMM_ERR_INDEX(LTTCOMM_SELECT_SESS) ] = "A session MUST be selected",
  50         [ LTTCOMM_ERR_INDEX(LTTCOMM_EXIST_SESS) ] = "Session name already exist",
  51 };
  52
  53 /*
  54  *  lttcom_get_readable_code
  55  *
  56  *  Return ptr to string representing a human readable
  57  *  error code from the lttcomm_return_code enum.
  58  *
  59  *  These code MUST be negative in other to treat that
  60  *  as an error value.
  61  */
  62 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  63 {
  64         int tmp_code = -code;
  65
  66         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  67                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  68         }
  69
  70         return "Unknown error code";
  71 }
  72
  73 /*
  74  *      lttcomm_connect_unix_sock
  75  *
  76  *      Connect to unix socket using the path name.
  77  */
  78 int lttcomm_connect_unix_sock(const char *pathname)
  79 {
  80         struct sockaddr_un sun;
  81         int fd;
  82         int ret = 1;
  83
  84         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  85         if (fd < 0) {
  86                 perror("socket");
  87                 goto error;
  88         }
  89
  90         memset(&sun, 0, sizeof(sun));
  91         sun.sun_family = AF_UNIX;
  92         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
  93
  94         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
  95         if (ret < 0) {
  96                 perror("connect");
  97                 goto error;
  98         }
  99
 100         return fd;
 101
 102 error:
 103         return -1;
 104 }
 105
 106 /*
 107  *      lttcomm_accept_unix_sock
 108  *
 109  *      Do an accept(2) on the sock and return the
 110  *      new file descriptor. The socket MUST be bind(2) before.
 111  */
 112 int lttcomm_accept_unix_sock(int sock)
 113 {
 114         int new_fd;
 115         struct sockaddr_un sun;
 116         socklen_t len = 0;
 117
 118         /* Blocking call */
 119         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 120         if (new_fd < 0) {
 121                 perror("accept");
 122                 goto error;
 123         }
 124
 125         return new_fd;
 126
 127 error:
 128         return -1;
 129 }
 130
 131 /*
 132  *      lttcomm_create_unix_sock
 133  *
 134  *      Creates a AF_UNIX local socket using pathname
 135  *      bind the socket upon creation and return the fd.
 136  */
 137 int lttcomm_create_unix_sock(const char *pathname)
 138 {
 139         struct sockaddr_un sun;
 140         int fd;
 141         int ret = -1;
 142
 143         /* Create server socket */
 144         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 145                 perror("socket");
 146                 goto error;
 147         }
 148
 149         memset(&sun, 0, sizeof(sun));
 150         sun.sun_family = AF_UNIX;
 151         strncpy(sun.sun_path, pathname, strlen(pathname));
 152
 153         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 154         if (ret < 0) {
 155                 perror("bind");
 156                 goto error;
 157         }
 158
 159         return fd;
 160
 161 error:
 162         return ret;
 163 }
 164
 165 /*
 166  *      lttcomm_listen_unix_sock
 167  *
 168  *      Make the socket listen using MAX_LISTEN.
 169  */
 170 int lttcomm_listen_unix_sock(int sock)
 171 {
 172         int ret;
 173
 174         ret = listen(sock, MAX_LISTEN);
 175         if (ret < 0) {
 176                 perror("listen");
 177         }
 178
 179         return ret;
 180 }
 181
 182 /*
 183  *      lttcomm_recv_unix_sock
 184  *
 185  *  Receive data of size len in put that data into
 186  *  the buf param. Using recvmsg API.
 187  *  Return the size of received data.
 188  */
 189 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 190 {
 191         struct msghdr msg;
 192         struct iovec iov[1];
 193         ssize_t ret = -1;
 194
 195         memset(&msg, 0, sizeof(msg));
 196
 197         iov[0].iov_base = buf;
 198         iov[0].iov_len = len;
 199         msg.msg_iov = iov;
 200         msg.msg_iovlen = 1;
 201
 202         ret = recvmsg(sock, &msg, 0);
 203         if (ret < 0) {
 204                 perror("recvmsg");
 205         }
 206
 207         return ret;
 208 }
 209
 210 /*
 211  *      lttcomm_send_unix_sock
 212  *
 213  *      Send buf data of size len. Using sendmsg API.
 214  *      Return the size of sent data.
 215  */
 216 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 217 {
 218         struct msghdr msg;
 219         struct iovec iov[1];
 220         ssize_t ret = -1;
 221
 222         memset(&msg, 0, sizeof(msg));
 223
 224         iov[0].iov_base = buf;
 225         iov[0].iov_len = len;
 226         msg.msg_iov = iov;
 227         msg.msg_iovlen = 1;
 228
 229         ret = sendmsg(sock, &msg, 0);
 230         if (ret < 0) {
 231                 perror("sendmsg");
 232         }
 233
 234         return ret;
 235 }
 236
 237 /*
 238  *  lttcomm_close_unix_sock
 239  *
 240  *  Shutdown cleanly a unix socket.
 241  */
 242 int lttcomm_close_unix_sock(int sock)
 243 {
 244         int ret;
 245
 246         /* Shutdown receptions and transmissions */
 247         ret = shutdown(sock, SHUT_RDWR);
 248         if (ret < 0) {
 249                 perror("shutdown");
 250         }
 251
 252         return ret;
 253 }