src/bin/lttng/commands/disable_events.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; only version 2
   7  * of the License.
   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 <popt.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <unistd.h>
  27
  28 #include "../command.h"
  29
  30 static char *opt_event_list;
  31 static int opt_kernel;
  32 static char *opt_channel_name;
  33 static char *opt_session_name;
  34 static int opt_userspace;
  35 static char *opt_cmd_name;
  36 static int opt_disable_all;
  37 static pid_t opt_pid;
  38
  39 enum {
  40         OPT_HELP = 1,
  41         OPT_USERSPACE,
  42 };
  43
  44 static struct lttng_handle *handle;
  45
  46 static struct poptOption long_options[] = {
  47         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  48         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  49         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  50         {"all-events",     'a', POPT_ARG_VAL, &opt_disable_all, 1, 0, 0},
  51         {"channel",        'c', POPT_ARG_STRING, &opt_channel_name, 0, 0, 0},
  52         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  53         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  54         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  55         {0, 0, 0, 0, 0, 0, 0}
  56 };
  57
  58 /*
  59  * usage
  60  */
  61 static void usage(FILE *ofp)
  62 {
  63         fprintf(ofp, "usage: lttng disable-event NAME[,NAME2,...] [options]\n");
  64         fprintf(ofp, "\n");
  65         fprintf(ofp, "  -h, --help               Show this help\n");
  66         fprintf(ofp, "  -s, --session            Apply on session name\n");
  67         fprintf(ofp, "  -c, --channel            Apply on this channel\n");
  68         fprintf(ofp, "  -a, --all-events         Disable all tracepoints\n");
  69         fprintf(ofp, "  -k, --kernel             Apply for the kernel tracer\n");
  70         fprintf(ofp, "  -u, --userspace [CMD]    Apply for the user-space tracer\n");
  71         fprintf(ofp, "                           If no CMD, the domain used is UST global\n");
  72         fprintf(ofp, "                           or else the domain is UST EXEC_NAME\n");
  73         fprintf(ofp, "  -p, --pid PID            If -u, apply to specific PID (domain: UST PID)\n");
  74         fprintf(ofp, "\n");
  75 }
  76
  77 /*
  78  *  disable_events
  79  *
  80  *  Disabling event using the lttng API.
  81  */
  82 static int disable_events(char *session_name)
  83 {
  84         int err, ret = CMD_SUCCESS;
  85         char *event_name, *channel_name = NULL;
  86         struct lttng_domain dom;
  87
  88         if (opt_channel_name == NULL) {
  89                 err = asprintf(&channel_name, DEFAULT_CHANNEL_NAME);
  90                 if (err < 0) {
  91                         ret = CMD_FATAL;
  92                         goto error;
  93                 }
  94         } else {
  95                 channel_name = opt_channel_name;
  96         }
  97
  98         if (opt_kernel && opt_userspace) {
  99                 ERR("Can't use -k/--kernel and -u/--userspace together");
 100                 ret = CMD_FATAL;
 101                 goto error;
 102         }
 103
 104         if (opt_kernel) {
 105                 dom.type = LTTNG_DOMAIN_KERNEL;
 106         } else if (opt_pid != 0) {
 107                 dom.type = LTTNG_DOMAIN_UST_PID;
 108                 dom.attr.pid = opt_pid;
 109                 DBG("PID %d set to lttng handle", opt_pid);
 110         } else if (opt_userspace && opt_cmd_name == NULL) {
 111                 dom.type = LTTNG_DOMAIN_UST;
 112                 DBG("UST global domain selected");
 113         } else if (opt_userspace && opt_cmd_name != NULL) {
 114                 dom.type = LTTNG_DOMAIN_UST_EXEC_NAME;
 115                 strncpy(dom.attr.exec_name, opt_cmd_name, NAME_MAX);
 116                 dom.attr.exec_name[NAME_MAX - 1] = '\0';
 117         } else {
 118                 ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 119                 ret = CMD_NOT_IMPLEMENTED;
 120                 goto error;
 121         }
 122
 123         handle = lttng_create_handle(session_name, &dom);
 124         if (handle == NULL) {
 125                 ret = -1;
 126                 goto error;
 127         }
 128
 129         if (opt_disable_all) {
 130                 ret = lttng_disable_event(handle, NULL, channel_name);
 131                 if (ret < 0) {
 132                         goto error;
 133                 }
 134
 135                 MSG("All %s events are disabled in channel %s",
 136                                 opt_kernel ? "kernel" : "UST", channel_name);
 137                 goto end;
 138         }
 139
 140         /* Strip event list */
 141         event_name = strtok(opt_event_list, ",");
 142         while (event_name != NULL) {
 143                 /* Kernel tracer action */
 144                 if (opt_kernel) {
 145                         DBG("Disabling kernel event %s in channel %s",
 146                                         event_name, channel_name);
 147                 } else if (opt_userspace) {             /* User-space tracer action */
 148                         if (opt_cmd_name != NULL || opt_pid) {
 149                                 MSG("Only supporting tracing all UST processes (-u) for now.");
 150                                 ret = CMD_NOT_IMPLEMENTED;
 151                                 goto error;
 152                         }
 153                         DBG("Disabling UST event %s in channel %s",
 154                                         event_name, channel_name);
 155                 } else {
 156                         ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
 157                         goto error;
 158                 }
 159
 160                 ret = lttng_disable_event(handle, event_name, channel_name);
 161                 if (ret < 0) {
 162                         MSG("Unable to disable %s event %s in channel %s",
 163                                         opt_kernel ? "kernel" : "UST", event_name,
 164                                         channel_name);
 165                 } else {
 166                         MSG("%s event %s disabled in channel %s",
 167                                         opt_kernel ? "kernel" : "UST", event_name,
 168                                         channel_name);
 169                 }
 170
 171                 /* Next event */
 172                 event_name = strtok(NULL, ",");
 173         }
 174
 175 end:
 176 error:
 177         if (opt_channel_name == NULL) {
 178                 free(channel_name);
 179         }
 180         lttng_destroy_handle(handle);
 181
 182         return ret;
 183 }
 184
 185 /*
 186  *  cmd_disable_events
 187  *
 188  *  Disable event to trace session
 189  */
 190 int cmd_disable_events(int argc, const char **argv)
 191 {
 192         int opt, ret;
 193         static poptContext pc;
 194         char *session_name = NULL;
 195
 196         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 197         poptReadDefaultConfig(pc, 0);
 198
 199         while ((opt = poptGetNextOpt(pc)) != -1) {
 200                 switch (opt) {
 201                 case OPT_HELP:
 202                         usage(stderr);
 203                         ret = CMD_SUCCESS;
 204                         goto end;
 205                 case OPT_USERSPACE:
 206                         opt_userspace = 1;
 207                         break;
 208                 default:
 209                         usage(stderr);
 210                         ret = CMD_UNDEFINED;
 211                         goto end;
 212                 }
 213         }
 214
 215         opt_event_list = (char*) poptGetArg(pc);
 216         if (opt_event_list == NULL && opt_disable_all == 0) {
 217                 ERR("Missing event name(s).\n");
 218                 usage(stderr);
 219                 ret = CMD_SUCCESS;
 220                 goto end;
 221         }
 222
 223         if (!opt_session_name) {
 224                 session_name = get_session_name();
 225                 if (session_name == NULL) {
 226                         ret = -1;
 227                         goto end;
 228                 }
 229         } else {
 230                 session_name = opt_session_name;
 231         }
 232
 233         ret = disable_events(session_name);
 234
 235 end:
 236         return ret;
 237 }