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