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         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "No event found",
  61 };
  62
  63 /*
  64  *  lttcom_get_readable_code
  65  *
  66  *  Return ptr to string representing a human readable
  67  *  error code from the lttcomm_return_code enum.
  68  *
  69  *  These code MUST be negative in other to treat that
  70  *  as an error value.
  71  */
  72 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  73 {
  74         int tmp_code = -code;
  75
  76         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  77                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  78         }
  79
  80         return "Unknown error code";
  81 }
  82
  83 /*
  84  *      lttcomm_connect_unix_sock
  85  *
  86  *      Connect to unix socket using the path name.
  87  */
  88 int lttcomm_connect_unix_sock(const char *pathname)
  89 {
  90         struct sockaddr_un sun;
  91         int fd;
  92         int ret = 1;
  93
  94         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  95         if (fd < 0) {
  96                 perror("socket");
  97                 goto error;
  98         }
  99
 100         memset(&sun, 0, sizeof(sun));
 101         sun.sun_family = AF_UNIX;
 102         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
 103
 104         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
 105         if (ret < 0) {
 106                 perror("connect");
 107                 goto error;
 108         }
 109
 110         return fd;
 111
 112 error:
 113         return -1;
 114 }
 115
 116 /*
 117  *      lttcomm_accept_unix_sock
 118  *
 119  *      Do an accept(2) on the sock and return the
 120  *      new file descriptor. The socket MUST be bind(2) before.
 121  */
 122 int lttcomm_accept_unix_sock(int sock)
 123 {
 124         int new_fd;
 125         struct sockaddr_un sun;
 126         socklen_t len = 0;
 127
 128         /* Blocking call */
 129         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 130         if (new_fd < 0) {
 131                 perror("accept");
 132                 goto error;
 133         }
 134
 135         return new_fd;
 136
 137 error:
 138         return -1;
 139 }
 140
 141 /*
 142  *      lttcomm_create_unix_sock
 143  *
 144  *      Creates a AF_UNIX local socket using pathname
 145  *      bind the socket upon creation and return the fd.
 146  */
 147 int lttcomm_create_unix_sock(const char *pathname)
 148 {
 149         struct sockaddr_un sun;
 150         int fd;
 151         int ret = -1;
 152
 153         /* Create server socket */
 154         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 155                 perror("socket");
 156                 goto error;
 157         }
 158
 159         memset(&sun, 0, sizeof(sun));
 160         sun.sun_family = AF_UNIX;
 161         strncpy(sun.sun_path, pathname, strlen(pathname));
 162
 163         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 164         if (ret < 0) {
 165                 perror("bind");
 166                 goto error;
 167         }
 168
 169         return fd;
 170
 171 error:
 172         return ret;
 173 }
 174
 175 /*
 176  *      lttcomm_listen_unix_sock
 177  *
 178  *      Make the socket listen using MAX_LISTEN.
 179  */
 180 int lttcomm_listen_unix_sock(int sock)
 181 {
 182         int ret;
 183
 184         ret = listen(sock, MAX_LISTEN);
 185         if (ret < 0) {
 186                 perror("listen");
 187         }
 188
 189         return ret;
 190 }
 191
 192 /*
 193  *      lttcomm_recv_unix_sock
 194  *
 195  *  Receive data of size len in put that data into
 196  *  the buf param. Using recvmsg API.
 197  *  Return the size of received data.
 198  */
 199 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 200 {
 201         struct msghdr msg;
 202         struct iovec iov[1];
 203         ssize_t ret = -1;
 204
 205         memset(&msg, 0, sizeof(msg));
 206
 207         iov[0].iov_base = buf;
 208         iov[0].iov_len = len;
 209         msg.msg_iov = iov;
 210         msg.msg_iovlen = 1;
 211
 212         ret = recvmsg(sock, &msg, 0);
 213         if (ret < 0) {
 214                 perror("recvmsg");
 215         }
 216
 217         return ret;
 218 }
 219
 220 /*
 221  *      lttcomm_send_unix_sock
 222  *
 223  *      Send buf data of size len. Using sendmsg API.
 224  *      Return the size of sent data.
 225  */
 226 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 227 {
 228         struct msghdr msg;
 229         struct iovec iov[1];
 230         ssize_t ret = -1;
 231
 232         memset(&msg, 0, sizeof(msg));
 233
 234         iov[0].iov_base = buf;
 235         iov[0].iov_len = len;
 236         msg.msg_iov = iov;
 237         msg.msg_iovlen = 1;
 238
 239         ret = sendmsg(sock, &msg, 0);
 240         if (ret < 0) {
 241                 perror("sendmsg");
 242         }
 243
 244         return ret;
 245 }
 246
 247 /*
 248  *  lttcomm_close_unix_sock
 249  *
 250  *  Shutdown cleanly a unix socket.
 251  */
 252 int lttcomm_close_unix_sock(int sock)
 253 {
 254         int ret;
 255
 256         /* Shutdown receptions and transmissions */
 257         ret = shutdown(sock, SHUT_RDWR);
 258         if (ret < 0) {
 259                 perror("shutdown");
 260         }
 261
 262         return ret;
 263 }