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(LTTCOMM_KERN_ENABLE_FAIL) ] = "Enable kernel event failed",
  55         [ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DISABLE_FAIL) ] = "Disable kernel event failed",
  56         [ LTTCOMM_ERR_INDEX(KCONSUMERD_COMMAND_SOCK_READY) ] = "Kconsumerd command socket ready",
  57         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SUCCESS_RECV_FD) ] = "Kconsumerd success on receiving fds",
  58         [ LTTCOMM_ERR_INDEX(KCONSUMERD_ERROR_RECV_FD) ] = "Kconsumerd error on receiving fds",
  59         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_ERROR) ] = "Kconsumerd error in polling thread",
  60         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_NVAL) ] = "Kconsumerd polling on closed fd",
  61         [ LTTCOMM_ERR_INDEX(KCONSUMERD_POLL_HUP) ] = "Kconsumerd all fd hung up",
  62         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_SUCCESS) ] = "Kconsumerd exiting normally",
  63         [ LTTCOMM_ERR_INDEX(KCONSUMERD_EXIT_FAILURE) ] = "Kconsumerd exiting on error",
  64         [ LTTCOMM_ERR_INDEX(KCONSUMERD_OUTFD_ERROR) ] = "Kconsumerd error opening the tracefile",
  65         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SPLICE_EBADF) ] = "Kconsumerd splice EBADF",
  66         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SPLICE_EINVAL) ] = "Kconsumerd splice EINVAL",
  67         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SPLICE_ENOMEM) ] = "Kconsumerd splice ENOMEM",
  68         [ LTTCOMM_ERR_INDEX(KCONSUMERD_SPLICE_ESPIPE) ] = "Kconsumerd splice ESPIPE",
  69         [ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "No event found",
  70 };
  71
  72 /*
  73  *  lttcom_get_readable_code
  74  *
  75  *  Return ptr to string representing a human readable
  76  *  error code from the lttcomm_return_code enum.
  77  *
  78  *  These code MUST be negative in other to treat that
  79  *  as an error value.
  80  */
  81 const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
  82 {
  83         int tmp_code = -code;
  84
  85         if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
  86                 return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
  87         }
  88
  89         return "Unknown error code";
  90 }
  91
  92 /*
  93  *      lttcomm_connect_unix_sock
  94  *
  95  *      Connect to unix socket using the path name.
  96  */
  97 int lttcomm_connect_unix_sock(const char *pathname)
  98 {
  99         struct sockaddr_un sun;
 100         int fd;
 101         int ret = 1;
 102
 103         fd = socket(PF_UNIX, SOCK_STREAM, 0);
 104         if (fd < 0) {
 105                 perror("socket");
 106                 goto error;
 107         }
 108
 109         memset(&sun, 0, sizeof(sun));
 110         sun.sun_family = AF_UNIX;
 111         strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
 112
 113         ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
 114         if (ret < 0) {
 115                 perror("connect");
 116                 goto error;
 117         }
 118
 119         return fd;
 120
 121 error:
 122         return -1;
 123 }
 124
 125 /*
 126  *      lttcomm_accept_unix_sock
 127  *
 128  *      Do an accept(2) on the sock and return the
 129  *      new file descriptor. The socket MUST be bind(2) before.
 130  */
 131 int lttcomm_accept_unix_sock(int sock)
 132 {
 133         int new_fd;
 134         struct sockaddr_un sun;
 135         socklen_t len = 0;
 136
 137         /* Blocking call */
 138         new_fd = accept(sock, (struct sockaddr *) &sun, &len);
 139         if (new_fd < 0) {
 140                 perror("accept");
 141                 goto error;
 142         }
 143
 144         return new_fd;
 145
 146 error:
 147         return -1;
 148 }
 149
 150 /*
 151  *      lttcomm_create_unix_sock
 152  *
 153  *      Creates a AF_UNIX local socket using pathname
 154  *      bind the socket upon creation and return the fd.
 155  */
 156 int lttcomm_create_unix_sock(const char *pathname)
 157 {
 158         struct sockaddr_un sun;
 159         int fd;
 160         int ret = -1;
 161
 162         /* Create server socket */
 163         if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
 164                 perror("socket");
 165                 goto error;
 166         }
 167
 168         memset(&sun, 0, sizeof(sun));
 169         sun.sun_family = AF_UNIX;
 170         strncpy(sun.sun_path, pathname, strlen(pathname));
 171
 172         ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
 173         if (ret < 0) {
 174                 perror("bind");
 175                 goto error;
 176         }
 177
 178         return fd;
 179
 180 error:
 181         return ret;
 182 }
 183
 184 /*
 185  *      lttcomm_listen_unix_sock
 186  *
 187  *      Make the socket listen using MAX_LISTEN.
 188  */
 189 int lttcomm_listen_unix_sock(int sock)
 190 {
 191         int ret;
 192
 193         ret = listen(sock, MAX_LISTEN);
 194         if (ret < 0) {
 195                 perror("listen");
 196         }
 197
 198         return ret;
 199 }
 200
 201 /*
 202  *      lttcomm_recv_unix_sock
 203  *
 204  *  Receive data of size len in put that data into
 205  *  the buf param. Using recvmsg API.
 206  *  Return the size of received data.
 207  */
 208 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 209 {
 210         struct msghdr msg;
 211         struct iovec iov[1];
 212         ssize_t ret = -1;
 213
 214         memset(&msg, 0, sizeof(msg));
 215
 216         iov[0].iov_base = buf;
 217         iov[0].iov_len = len;
 218         msg.msg_iov = iov;
 219         msg.msg_iovlen = 1;
 220
 221         ret = recvmsg(sock, &msg, 0);
 222         if (ret < 0) {
 223                 perror("recvmsg");
 224         }
 225
 226         return ret;
 227 }
 228
 229 /*
 230  *      lttcomm_send_unix_sock
 231  *
 232  *      Send buf data of size len. Using sendmsg API.
 233  *      Return the size of sent data.
 234  */
 235 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 236 {
 237         struct msghdr msg;
 238         struct iovec iov[1];
 239         ssize_t ret = -1;
 240
 241         memset(&msg, 0, sizeof(msg));
 242
 243         iov[0].iov_base = buf;
 244         iov[0].iov_len = len;
 245         msg.msg_iov = iov;
 246         msg.msg_iovlen = 1;
 247
 248         ret = sendmsg(sock, &msg, 0);
 249         if (ret < 0) {
 250                 perror("sendmsg");
 251         }
 252
 253         return ret;
 254 }
 255
 256 /*
 257  *  lttcomm_close_unix_sock
 258  *
 259  *  Shutdown cleanly a unix socket.
 260  */
 261 int lttcomm_close_unix_sock(int sock)
 262 {
 263         int ret;
 264
 265         /* Shutdown receptions and transmissions */
 266         ret = shutdown(sock, SHUT_RDWR);
 267         if (ret < 0) {
 268                 perror("shutdown");
 269         }
 270
 271         return ret;
 272 }