| 1 | /* |
| 2 | * lttd |
| 3 | * |
| 4 | * Linux Trace Toolkit Daemon |
| 5 | * |
| 6 | * This is a simple daemon that reads a few LTTng debugfs channels and saves |
| 7 | * them in a trace on the virtual file system. |
| 8 | * |
| 9 | * CPU hot-plugging is supported using inotify. |
| 10 | * |
| 11 | * Copyright 2009-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 12 | * Copyright 2010 - Michael Sills-Lavoie <michael.sills-lavoie@polymtl.ca> |
| 13 | * Copyright 2010 - Oumarou Dicko <oumarou.dicko@polymtl.ca> |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or modify |
| 16 | * it under the terms of the GNU General Public License as published by |
| 17 | * the Free Software Foundation; either version 2 of the License, or |
| 18 | * (at your option) any later version. |
| 19 | * |
| 20 | * This program is distributed in the hope that it will be useful, |
| 21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 23 | * GNU General Public License for more details. |
| 24 | * |
| 25 | * You should have received a copy of the GNU General Public License along |
| 26 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 27 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 28 | */ |
| 29 | |
| 30 | #ifdef HAVE_CONFIG_H |
| 31 | #include <config.h> |
| 32 | #endif |
| 33 | |
| 34 | #define _REENTRANT |
| 35 | #define _GNU_SOURCE |
| 36 | |
| 37 | #include <stdio.h> |
| 38 | #include <stdlib.h> |
| 39 | #include <signal.h> |
| 40 | #include <errno.h> |
| 41 | |
| 42 | #include <liblttd/liblttd.h> |
| 43 | #include <liblttd/liblttdvfs.h> |
| 44 | |
| 45 | struct liblttd_instance* instance; |
| 46 | |
| 47 | static char *trace_name = NULL; |
| 48 | static char *channel_name = NULL; |
| 49 | static int daemon_mode = 0; |
| 50 | static int append_mode = 0; |
| 51 | static unsigned long num_threads = 1; |
| 52 | static int dump_flight_only = 0; |
| 53 | static int dump_normal_only = 0; |
| 54 | static int verbose_mode = 0; |
| 55 | |
| 56 | |
| 57 | /* Args : |
| 58 | * |
| 59 | * -t directory Directory name of the trace to write to. Will be created. |
| 60 | * -c directory Root directory of the debugfs trace channels. |
| 61 | * -d Run in background (daemon). |
| 62 | * -a Trace append mode. |
| 63 | * -s Send SIGUSR1 to parent when ready for IO. |
| 64 | */ |
| 65 | void show_arguments(void) |
| 66 | { |
| 67 | printf("Please use the following arguments :\n"); |
| 68 | printf("\n"); |
| 69 | printf("-t directory Directory name of the trace to write to.\n" |
| 70 | " It will be created.\n"); |
| 71 | printf("-c directory Root directory of the debugfs trace channels.\n"); |
| 72 | printf("-d Run in background (daemon).\n"); |
| 73 | printf("-a Append to an possibly existing trace.\n"); |
| 74 | printf("-N Number of threads to start.\n"); |
| 75 | printf("-f Dump only flight recorder channels.\n"); |
| 76 | printf("-n Dump only normal channels.\n"); |
| 77 | printf("-v Verbose mode.\n"); |
| 78 | printf("\n"); |
| 79 | } |
| 80 | |
| 81 | |
| 82 | /* parse_arguments |
| 83 | * |
| 84 | * Parses the command line arguments. |
| 85 | * |
| 86 | * Returns 1 if the arguments were correct, but doesn't ask for program |
| 87 | * continuation. Returns -1 if the arguments are incorrect, or 0 if OK. |
| 88 | */ |
| 89 | int parse_arguments(int argc, char **argv) |
| 90 | { |
| 91 | int ret = 0; |
| 92 | int argn = 1; |
| 93 | |
| 94 | if(argc == 2) { |
| 95 | if(strcmp(argv[1], "-h") == 0) { |
| 96 | return 1; |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | while(argn < argc) { |
| 101 | |
| 102 | switch(argv[argn][0]) { |
| 103 | case '-': |
| 104 | switch(argv[argn][1]) { |
| 105 | case 't': |
| 106 | if(argn+1 < argc) { |
| 107 | trace_name = argv[argn+1]; |
| 108 | argn++; |
| 109 | } |
| 110 | break; |
| 111 | case 'c': |
| 112 | if(argn+1 < argc) { |
| 113 | channel_name = argv[argn+1]; |
| 114 | argn++; |
| 115 | } |
| 116 | break; |
| 117 | case 'd': |
| 118 | daemon_mode = 1; |
| 119 | break; |
| 120 | case 'a': |
| 121 | append_mode = 1; |
| 122 | break; |
| 123 | case 'N': |
| 124 | if(argn+1 < argc) { |
| 125 | num_threads = strtoul(argv[argn+1], NULL, 0); |
| 126 | argn++; |
| 127 | } |
| 128 | break; |
| 129 | case 'f': |
| 130 | dump_flight_only = 1; |
| 131 | break; |
| 132 | case 'n': |
| 133 | dump_normal_only = 1; |
| 134 | break; |
| 135 | case 'v': |
| 136 | verbose_mode = 1; |
| 137 | break; |
| 138 | default: |
| 139 | printf("Invalid argument '%s'.\n", argv[argn]); |
| 140 | printf("\n"); |
| 141 | ret = -1; |
| 142 | } |
| 143 | break; |
| 144 | default: |
| 145 | printf("Invalid argument '%s'.\n", argv[argn]); |
| 146 | printf("\n"); |
| 147 | ret = -1; |
| 148 | } |
| 149 | argn++; |
| 150 | } |
| 151 | |
| 152 | if(trace_name == NULL) { |
| 153 | printf("Please specify a trace name.\n"); |
| 154 | printf("\n"); |
| 155 | ret = -1; |
| 156 | } |
| 157 | |
| 158 | if(channel_name == NULL) { |
| 159 | printf("Please specify a channel name.\n"); |
| 160 | printf("\n"); |
| 161 | ret = -1; |
| 162 | } |
| 163 | |
| 164 | return ret; |
| 165 | } |
| 166 | |
| 167 | void show_info(void) |
| 168 | { |
| 169 | printf("Linux Trace Toolkit Trace Daemon " VERSION "\n"); |
| 170 | printf("\n"); |
| 171 | printf("Reading from debugfs directory : %s\n", channel_name); |
| 172 | printf("Writing to trace directory : %s\n", trace_name); |
| 173 | printf("\n"); |
| 174 | } |
| 175 | |
| 176 | |
| 177 | /* signal handling */ |
| 178 | |
| 179 | static void handler(int signo) |
| 180 | { |
| 181 | printf("Signal %d received : exiting cleanly\n", signo); |
| 182 | liblttd_stop_instance(instance); |
| 183 | } |
| 184 | |
| 185 | int main(int argc, char ** argv) |
| 186 | { |
| 187 | int ret = 0; |
| 188 | struct sigaction act; |
| 189 | |
| 190 | ret = parse_arguments(argc, argv); |
| 191 | |
| 192 | if(ret != 0) show_arguments(); |
| 193 | if(ret < 0) return EINVAL; |
| 194 | if(ret > 0) return 0; |
| 195 | |
| 196 | show_info(); |
| 197 | |
| 198 | /* Connect the signal handlers */ |
| 199 | act.sa_handler = handler; |
| 200 | act.sa_flags = 0; |
| 201 | sigemptyset(&(act.sa_mask)); |
| 202 | sigaddset(&(act.sa_mask), SIGTERM); |
| 203 | sigaddset(&(act.sa_mask), SIGQUIT); |
| 204 | sigaddset(&(act.sa_mask), SIGINT); |
| 205 | sigaction(SIGTERM, &act, NULL); |
| 206 | sigaction(SIGQUIT, &act, NULL); |
| 207 | sigaction(SIGINT, &act, NULL); |
| 208 | |
| 209 | if(daemon_mode) { |
| 210 | ret = daemon(0, 0); |
| 211 | |
| 212 | if(ret == -1) { |
| 213 | perror("An error occured while daemonizing."); |
| 214 | exit(-1); |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | struct liblttd_callbacks* callbacks = |
| 219 | liblttdvfs_new_callbacks(trace_name, append_mode, verbose_mode); |
| 220 | |
| 221 | instance = liblttd_new_instance(callbacks, channel_name, num_threads, |
| 222 | dump_flight_only, dump_normal_only, |
| 223 | verbose_mode); |
| 224 | |
| 225 | if(!instance) { |
| 226 | perror("An error occured while creating the liblttd instance"); |
| 227 | return ret; |
| 228 | } |
| 229 | |
| 230 | liblttd_start_instance(instance); |
| 231 | |
| 232 | return ret; |
| 233 | } |
| 234 | |