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_NO_TRACEABLE) ] = "App is not traceable",
  48         [ LTTCOMM_ERR_INDEX(LTTCOMM_SELECT_SESS) ] = "A session MUST be selected",
  49         [ LTTCOMM_ERR_INDEX(LTTCOMM_EXIST_SESS) ] = "Session name already exist",
  50 };
  51
  52 /*
  53  *  lttcom_get_readable_code
  54  *
  55  *  Return ptr to string representing a human readable
  56  *  error code from the lttcomm_return_code enum.
  57  *
  58  *  These code MUST be negative in other to treat that
  59  *  as an error value.
  60  */
  61 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  62 {
  63         int tmp_code = -code;
  64
  65         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  66                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  67         }
  68
  69         return "Unknown error code";
  70 }
  71
  72 /*
  73  *      lttcomm_connect_unix_sock
  74  *
  75  *      Connect to unix socket using the path name.
  76  */
  77 int lttcomm_connect_unix_sock(const char *pathname)
  78 {
  79         struct sockaddr_un sun;
  80         int fd;
  81         int ret = 1;
  82
  83         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  84         if (fd < 0) {
  85                 perror("socket");
  86                 goto error;
  87         }
  88
  89         memset(&sun, 0, sizeof(sun));
  90         sun.sun_family = AF_UNIX;
  91         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
  92
  93         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
  94         if (ret < 0) {
  95                 perror("connect");
  96                 goto error;
  97         }
  98
  99         return fd;
 100
 101 error:
 102         return -1;
 103 }
 104
 105 /*
 106  *      lttcomm_accept_unix_sock
 107  *
 108  *      Do an accept(2) on the sock and return the
 109  *      new file descriptor. The socket MUST be bind(2) before.
 110  */
 111 int lttcomm_accept_unix_sock(int sock)
 112 {
 113         int new_fd;
 114         struct sockaddr_un sun;
 115         socklen_t len = 0;
 116
 117         /* Blocking call */
 118         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 119         if (new_fd < 0) {
 120                 perror("accept");
 121                 goto error;
 122         }
 123
 124         return new_fd;
 125
 126 error:
 127         return -1;
 128 }
 129
 130 /*
 131  *      lttcomm_create_unix_sock
 132  *
 133  *      Creates a AF_UNIX local socket using pathname
 134  *      bind the socket upon creation and return the fd.
 135  */
 136 int lttcomm_create_unix_sock(const char *pathname)
 137 {
 138         struct sockaddr_un sun;
 139         int fd;
 140         int ret = -1;
 141
 142         /* Create server socket */
 143         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 144                 perror("socket");
 145                 goto error;
 146         }
 147
 148         memset(&sun, 0, sizeof(sun));
 149         sun.sun_family = AF_UNIX;
 150         strncpy(sun.sun_path, pathname, strlen(pathname));
 151
 152         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 153         if (ret < 0) {
 154                 perror("bind");
 155                 goto error;
 156         }
 157
 158         return fd;
 159
 160 error:
 161         return ret;
 162 }
 163
 164 /*
 165  *      lttcomm_listen_unix_sock
 166  *
 167  *      Make the socket listen using MAX_LISTEN.
 168  */
 169 int lttcomm_listen_unix_sock(int sock)
 170 {
 171         int ret;
 172
 173         ret = listen(sock, MAX_LISTEN);
 174         if (ret < 0) {
 175                 perror("listen");
 176         }
 177
 178         return ret;
 179 }
 180
 181 /*
 182  *      lttcomm_recv_unix_sock
 183  *
 184  *  Receive data of size len in put that data into
 185  *  the buf param. Using recvmsg API.
 186  *  Return the size of received data.
 187  */
 188 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 189 {
 190         struct msghdr msg;
 191         struct iovec iov[1];
 192         ssize_t ret = -1;
 193
 194         memset(&msg, 0, sizeof(msg));
 195
 196         iov[0].iov_base = buf;
 197         iov[0].iov_len = len;
 198         msg.msg_iov = iov;
 199         msg.msg_iovlen = 1;
 200
 201         ret = recvmsg(sock, &msg, 0);
 202         if (ret < 0) {
 203                 perror("recvmsg");
 204         }
 205
 206         return ret;
 207 }
 208
 209 /*
 210  *      lttcomm_send_unix_sock
 211  *
 212  *      Send buf data of size len. Using sendmsg API.
 213  *      Return the size of sent data.
 214  */
 215 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 216 {
 217         struct msghdr msg;
 218         struct iovec iov[1];
 219         ssize_t ret = -1;
 220
 221         memset(&msg, 0, sizeof(msg));
 222
 223         iov[0].iov_base = buf;
 224         iov[0].iov_len = len;
 225         msg.msg_iov = iov;
 226         msg.msg_iovlen = 1;
 227
 228         ret = sendmsg(sock, &msg, 0);
 229         if (ret < 0) {
 230                 perror("sendmsg");
 231         }
 232
 233         return ret;
 234 }
 235
 236 /*
 237  *  lttcomm_close_unix_sock
 238  *
 239  *  Shutdown cleanly a unix socket.
 240  */
 241 int lttcomm_close_unix_sock(int sock)
 242 {
 243         int ret;
 244
 245         /* Shutdown receptions and transmissions */
 246         ret = shutdown(sock, SHUT_RDWR);
 247         if (ret < 0) {
 248                 perror("shutdown");
 249         }
 250
 251         return ret;
 252 }