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(LTTCOMM_KERN_NA) ] = "Kernel tracer not available",
  52         [ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_SESS_FAIL) ] = "Kernel create session failed",
  53         [ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_FAIL) ] = "Kernel create channel failed",
  54         [ LTTCOMM_ERR_INDEX(KCONSUMERD_COMMAND_SOCK_READY) ] = "Kconsumerd command socket ready",
  55         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SUCCESS_RECV_FD) ] = "Kconsumerd success on receiving fds",
  56         [ LTTCOMM_ERR_INDEX(KCONSUMERD_ERROR_RECV_FD) ] = "Kconsumerd error on receiving fds",
  57         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_ERROR) ] = "Kconsumerd error in polling thread",
  58         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_NVAL) ] = "Kconsumerd polling on closed fd",
  59         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_HUP) ] = "Kconsumerd all fd hung up",
  60         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_SUCCESS) ] = "Kconsumerd exiting normally",
  61         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_FAILURE) ] = "Kconsumerd exiting on error",
  62         [ LTTCOMM_ERR_INDEX(KCONSUMERD_OUTFD_ERROR) ] = "Kconsumerd error opening the tracefile",
  63         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "No event found",
  64 };
  65
  66 /*
  67  *  lttcom_get_readable_code
  68  *
  69  *  Return ptr to string representing a human readable
  70  *  error code from the lttcomm_return_code enum.
  71  *
  72  *  These code MUST be negative in other to treat that
  73  *  as an error value.
  74  */
  75 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  76 {
  77         int tmp_code = -code;
  78
  79         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  80                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  81         }
  82
  83         return "Unknown error code";
  84 }
  85
  86 /*
  87  *      lttcomm_connect_unix_sock
  88  *
  89  *      Connect to unix socket using the path name.
  90  */
  91 int lttcomm_connect_unix_sock(const char *pathname)
  92 {
  93         struct sockaddr_un sun;
  94         int fd;
  95         int ret = 1;
  96
  97         fd = socket(PF_UNIX, SOCK_STREAM, 0);
  98         if (fd < 0) {
  99                 perror("socket");
 100                 goto error;
 101         }
 102
 103         memset(&sun, 0, sizeof(sun));
 104         sun.sun_family = AF_UNIX;
 105         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
 106
 107         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
 108         if (ret < 0) {
 109                 perror("connect");
 110                 goto error;
 111         }
 112
 113         return fd;
 114
 115 error:
 116         return -1;
 117 }
 118
 119 /*
 120  *      lttcomm_accept_unix_sock
 121  *
 122  *      Do an accept(2) on the sock and return the
 123  *      new file descriptor. The socket MUST be bind(2) before.
 124  */
 125 int lttcomm_accept_unix_sock(int sock)
 126 {
 127         int new_fd;
 128         struct sockaddr_un sun;
 129         socklen_t len = 0;
 130
 131         /* Blocking call */
 132         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 133         if (new_fd < 0) {
 134                 perror("accept");
 135                 goto error;
 136         }
 137
 138         return new_fd;
 139
 140 error:
 141         return -1;
 142 }
 143
 144 /*
 145  *      lttcomm_create_unix_sock
 146  *
 147  *      Creates a AF_UNIX local socket using pathname
 148  *      bind the socket upon creation and return the fd.
 149  */
 150 int lttcomm_create_unix_sock(const char *pathname)
 151 {
 152         struct sockaddr_un sun;
 153         int fd;
 154         int ret = -1;
 155
 156         /* Create server socket */
 157         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 158                 perror("socket");
 159                 goto error;
 160         }
 161
 162         memset(&sun, 0, sizeof(sun));
 163         sun.sun_family = AF_UNIX;
 164         strncpy(sun.sun_path, pathname, strlen(pathname));
 165
 166         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 167         if (ret < 0) {
 168                 perror("bind");
 169                 goto error;
 170         }
 171
 172         return fd;
 173
 174 error:
 175         return ret;
 176 }
 177
 178 /*
 179  *      lttcomm_listen_unix_sock
 180  *
 181  *      Make the socket listen using MAX_LISTEN.
 182  */
 183 int lttcomm_listen_unix_sock(int sock)
 184 {
 185         int ret;
 186
 187         ret = listen(sock, MAX_LISTEN);
 188         if (ret < 0) {
 189                 perror("listen");
 190         }
 191
 192         return ret;
 193 }
 194
 195 /*
 196  *      lttcomm_recv_unix_sock
 197  *
 198  *  Receive data of size len in put that data into
 199  *  the buf param. Using recvmsg API.
 200  *  Return the size of received data.
 201  */
 202 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 203 {
 204         struct msghdr msg;
 205         struct iovec iov[1];
 206         ssize_t ret = -1;
 207
 208         memset(&msg, 0, sizeof(msg));
 209
 210         iov[0].iov_base = buf;
 211         iov[0].iov_len = len;
 212         msg.msg_iov = iov;
 213         msg.msg_iovlen = 1;
 214
 215         ret = recvmsg(sock, &msg, 0);
 216         if (ret < 0) {
 217                 perror("recvmsg");
 218         }
 219
 220         return ret;
 221 }
 222
 223 /*
 224  *      lttcomm_send_unix_sock
 225  *
 226  *      Send buf data of size len. Using sendmsg API.
 227  *      Return the size of sent data.
 228  */
 229 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 230 {
 231         struct msghdr msg;
 232         struct iovec iov[1];
 233         ssize_t ret = -1;
 234
 235         memset(&msg, 0, sizeof(msg));
 236
 237         iov[0].iov_base = buf;
 238         iov[0].iov_len = len;
 239         msg.msg_iov = iov;
 240         msg.msg_iovlen = 1;
 241
 242         ret = sendmsg(sock, &msg, 0);
 243         if (ret < 0) {
 244                 perror("sendmsg");
 245         }
 246
 247         return ret;
 248 }
 249
 250 /*
 251  *  lttcomm_close_unix_sock
 252  *
 253  *  Shutdown cleanly a unix socket.
 254  */
 255 int lttcomm_close_unix_sock(int sock)
 256 {
 257         int ret;
 258
 259         /* Shutdown receptions and transmissions */
 260         ret = shutdown(sock, SHUT_RDWR);
 261         if (ret < 0) {
 262                 perror("shutdown");
 263         }
 264
 265         return ret;
 266 }