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         [ LTTCOMM_ERR_INDEX(KCONSUMERD_COMMAND_SOCK_READY) ] = "Kconsumerd command socket ready",
  52         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SUCCESS_RECV_FD) ] = "Kconsumerd success on receiving fds",
  53         [ LTTCOMM_ERR_INDEX(KCONSUMERD_ERROR_RECV_FD) ] = "Kconsumerd error on receiving fds",
  54         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_ERROR) ] = "Kconsumerd error in polling thread",
  55         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_NVAL) ] = "Kconsumerd polling on closed fd",
  56         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_HUP) ] = "Kconsumerd all fd hung up",
  57         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_SUCCESS) ] = "Kconsumerd exiting normally",
  58         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_FAILURE) ] = "Kconsumerd exiting on error",
  59         [ LTTCOMM_ERR_INDEX(KCONSUMERD_OUTFD_ERROR) ] = "Kconsumerd error opening the tracefile",
  60 };
  61
  62 /*
  63  *  lttcom_get_readable_code
  64  *
  65  *  Return ptr to string representing a human readable
  66  *  error code from the lttcomm_return_code enum.
  67  *
  68  *  These code MUST be negative in other to treat that
  69  *  as an error value.
  70  */
  71 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  72 {
  73         int tmp_code = -code;
  74
  75         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  76                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  77         }
  78
  79         return "Unknown error code";
  80 }
  81
  82 /*
  83  *      lttcomm_connect_unix_sock
  84  *
  85  *      Connect to unix socket using the path name.
  86  */
  87 int lttcomm_connect_unix_sock(const char *pathname)
  88 {
  89         struct sockaddr_un sun;
  90         int fd;
  91         int ret = 1;
  92
  93         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  94         if (fd < 0) {
  95                 perror("socket");
  96                 goto error;
  97         }
  98
  99         memset(&sun, 0, sizeof(sun));
 100         sun.sun_family = AF_UNIX;
 101         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
 102
 103         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
 104         if (ret < 0) {
 105                 perror("connect");
 106                 goto error;
 107         }
 108
 109         return fd;
 110
 111 error:
 112         return -1;
 113 }
 114
 115 /*
 116  *      lttcomm_accept_unix_sock
 117  *
 118  *      Do an accept(2) on the sock and return the
 119  *      new file descriptor. The socket MUST be bind(2) before.
 120  */
 121 int lttcomm_accept_unix_sock(int sock)
 122 {
 123         int new_fd;
 124         struct sockaddr_un sun;
 125         socklen_t len = 0;
 126
 127         /* Blocking call */
 128         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 129         if (new_fd < 0) {
 130                 perror("accept");
 131                 goto error;
 132         }
 133
 134         return new_fd;
 135
 136 error:
 137         return -1;
 138 }
 139
 140 /*
 141  *      lttcomm_create_unix_sock
 142  *
 143  *      Creates a AF_UNIX local socket using pathname
 144  *      bind the socket upon creation and return the fd.
 145  */
 146 int lttcomm_create_unix_sock(const char *pathname)
 147 {
 148         struct sockaddr_un sun;
 149         int fd;
 150         int ret = -1;
 151
 152         /* Create server socket */
 153         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 154                 perror("socket");
 155                 goto error;
 156         }
 157
 158         memset(&sun, 0, sizeof(sun));
 159         sun.sun_family = AF_UNIX;
 160         strncpy(sun.sun_path, pathname, strlen(pathname));
 161
 162         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 163         if (ret < 0) {
 164                 perror("bind");
 165                 goto error;
 166         }
 167
 168         return fd;
 169
 170 error:
 171         return ret;
 172 }
 173
 174 /*
 175  *      lttcomm_listen_unix_sock
 176  *
 177  *      Make the socket listen using MAX_LISTEN.
 178  */
 179 int lttcomm_listen_unix_sock(int sock)
 180 {
 181         int ret;
 182
 183         ret = listen(sock, MAX_LISTEN);
 184         if (ret < 0) {
 185                 perror("listen");
 186         }
 187
 188         return ret;
 189 }
 190
 191 /*
 192  *      lttcomm_recv_unix_sock
 193  *
 194  *  Receive data of size len in put that data into
 195  *  the buf param. Using recvmsg API.
 196  *  Return the size of received data.
 197  */
 198 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 199 {
 200         struct msghdr msg;
 201         struct iovec iov[1];
 202         ssize_t ret = -1;
 203
 204         memset(&msg, 0, sizeof(msg));
 205
 206         iov[0].iov_base = buf;
 207         iov[0].iov_len = len;
 208         msg.msg_iov = iov;
 209         msg.msg_iovlen = 1;
 210
 211         ret = recvmsg(sock, &msg, 0);
 212         if (ret < 0) {
 213                 perror("recvmsg");
 214         }
 215
 216         return ret;
 217 }
 218
 219 /*
 220  *      lttcomm_send_unix_sock
 221  *
 222  *      Send buf data of size len. Using sendmsg API.
 223  *      Return the size of sent data.
 224  */
 225 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 226 {
 227         struct msghdr msg;
 228         struct iovec iov[1];
 229         ssize_t ret = -1;
 230
 231         memset(&msg, 0, sizeof(msg));
 232
 233         iov[0].iov_base = buf;
 234         iov[0].iov_len = len;
 235         msg.msg_iov = iov;
 236         msg.msg_iovlen = 1;
 237
 238         ret = sendmsg(sock, &msg, 0);
 239         if (ret < 0) {
 240                 perror("sendmsg");
 241         }
 242
 243         return ret;
 244 }
 245
 246 /*
 247  *  lttcomm_close_unix_sock
 248  *
 249  *  Shutdown cleanly a unix socket.
 250  */
 251 int lttcomm_close_unix_sock(int sock)
 252 {
 253         int ret;
 254
 255         /* Shutdown receptions and transmissions */
 256         ret = shutdown(sock, SHUT_RDWR);
 257         if (ret < 0) {
 258                 perror("shutdown");
 259         }
 260
 261         return ret;
 262 }