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 "../cmd.h"
  29 #include "../conf.h"
  30 #include "../utils.h"
  31
  32 static char *opt_event_list;
  33 static int opt_kernel;
  34 static char *opt_channel_name;
  35 static char *opt_session_name;
  36 static int opt_pid_all;
  37 static int opt_userspace;
  38 static char *opt_cmd_name;
  39 static int opt_disable_all;
  40 static pid_t opt_pid;
  41
  42 enum {
  43         OPT_HELP = 1,
  44         OPT_USERSPACE,
  45 };
  46
  47 static struct lttng_handle *handle;
  48
  49 static struct poptOption long_options[] = {
  50         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  51         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  52         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  53         {"all-events",     'a', POPT_ARG_VAL, &opt_disable_all, 1, 0, 0},
  54         {"channel",        'c', POPT_ARG_STRING, &opt_channel_name, 0, 0, 0},
  55         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  56         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  57         {"all",            0,   POPT_ARG_VAL, &opt_pid_all, 1, 0, 0},
  58         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  59         {0, 0, 0, 0, 0, 0, 0}
  60 };
  61
  62 /*
  63  * usage
  64  */
  65 static void usage(FILE *ofp)
  66 {
  67         fprintf(ofp, "usage: lttng disable-event NAME[,NAME2,...] [options]\n");
  68         fprintf(ofp, "\n");
  69         fprintf(ofp, "  -h, --help               Show this help\n");
  70         fprintf(ofp, "  -s, --session            Apply on session name\n");
  71         fprintf(ofp, "  -c, --channel            Apply on this channel\n");
  72         fprintf(ofp, "  -a, --all-events         Disable all tracepoints\n");
  73         fprintf(ofp, "  -k, --kernel             Apply for the kernel tracer\n");
  74         fprintf(ofp, "  -u, --userspace [CMD]    Apply for the user-space tracer\n");
  75         fprintf(ofp, "      --all                If -u, apply on all traceable apps\n");
  76         fprintf(ofp, "  -p, --pid PID            If -u, apply on a specific PID\n");
  77         fprintf(ofp, "\n");
  78 }
  79
  80 /*
  81  *  disable_events
  82  *
  83  *  Disabling event using the lttng API.
  84  */
  85 static int disable_events(char *session_name)
  86 {
  87         int err, ret = CMD_SUCCESS;
  88         char *event_name, *channel_name = NULL;
  89         struct lttng_domain dom;
  90
  91         if (opt_channel_name == NULL) {
  92                 err = asprintf(&channel_name, DEFAULT_CHANNEL_NAME);
  93                 if (err < 0) {
  94                         ret = CMD_FATAL;
  95                         goto error;
  96                 }
  97         } else {
  98                 channel_name = opt_channel_name;
  99         }
 100
 101         if (opt_kernel) {
 102                 dom.type = LTTNG_DOMAIN_KERNEL;
 103         } else if (opt_pid != 0) {
 104                 dom.type = LTTNG_DOMAIN_UST_PID;
 105                 dom.attr.pid = opt_pid;
 106                 DBG("PID %d set to lttng handle", opt_pid);
 107         } else if (opt_userspace && opt_cmd_name == NULL) {
 108                 dom.type = LTTNG_DOMAIN_UST;
 109                 DBG("UST global domain selected");
 110         } else if (opt_userspace && opt_cmd_name != NULL) {
 111                 dom.type = LTTNG_DOMAIN_UST_EXEC_NAME;
 112                 strncpy(dom.attr.exec_name, opt_cmd_name, NAME_MAX);
 113         } else {
 114                 ERR("Please specify a tracer (--kernel or --userspace)");
 115                 ret = CMD_NOT_IMPLEMENTED;
 116                 goto error;
 117         }
 118
 119         handle = lttng_create_handle(session_name, &dom);
 120         if (handle == NULL) {
 121                 ret = -1;
 122                 goto error;
 123         }
 124
 125         if (opt_disable_all) {
 126                 ret = lttng_disable_event(handle, NULL, channel_name);
 127                 if (ret < 0) {
 128                         goto error;
 129                 }
 130
 131                 MSG("All %s events are disabled in channel %s",
 132                                 opt_kernel ? "kernel" : "UST", channel_name);
 133                 goto end;
 134         }
 135
 136         /* Strip event list */
 137         event_name = strtok(opt_event_list, ",");
 138         while (event_name != NULL) {
 139                 /* Kernel tracer action */
 140                 if (opt_kernel) {
 141                         DBG("Disabling kernel event %s in channel %s",
 142                                         event_name, channel_name);
 143                 } else if (opt_userspace) {             /* User-space tracer action */
 144                         if (!opt_pid_all) {
 145                                 MSG("Only supporting tracing all UST processes (-u --all) for now.");
 146                                 ret = CMD_NOT_IMPLEMENTED;
 147                                 goto error;
 148                         }
 149                         DBG("Disabling UST event %s in channel %s",
 150                                         event_name, channel_name);
 151                 } else {
 152                         ERR("Please specify a tracer (--kernel or --userspace)");
 153                         goto error;
 154                 }
 155
 156                 ret = lttng_disable_event(handle, event_name, channel_name);
 157                 if (ret < 0) {
 158                         MSG("Unable to disable %s event %s in channel %s",
 159                                         opt_kernel ? "kernel" : "UST", event_name,
 160                                         channel_name);
 161                 } else {
 162                         MSG("%s event %s disabled in channel %s",
 163                                         opt_kernel ? "kernel" : "UST", event_name,
 164                                         channel_name);
 165                 }
 166
 167                 /* Next event */
 168                 event_name = strtok(NULL, ",");
 169         }
 170
 171 end:
 172 error:
 173         if (opt_channel_name == NULL) {
 174                 free(channel_name);
 175         }
 176         lttng_destroy_handle(handle);
 177
 178         return ret;
 179 }
 180
 181 /*
 182  *  cmd_disable_events
 183  *
 184  *  Disable event to trace session
 185  */
 186 int cmd_disable_events(int argc, const char **argv)
 187 {
 188         int opt, ret;
 189         static poptContext pc;
 190         char *session_name = NULL;
 191
 192         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 193         poptReadDefaultConfig(pc, 0);
 194
 195         while ((opt = poptGetNextOpt(pc)) != -1) {
 196                 switch (opt) {
 197                 case OPT_HELP:
 198                         usage(stderr);
 199                         ret = CMD_SUCCESS;
 200                         goto end;
 201                 case OPT_USERSPACE:
 202                         opt_userspace = 1;
 203                         break;
 204                 default:
 205                         usage(stderr);
 206                         ret = CMD_UNDEFINED;
 207                         goto end;
 208                 }
 209         }
 210
 211         opt_event_list = (char*) poptGetArg(pc);
 212         if (opt_event_list == NULL && opt_disable_all == 0) {
 213                 ERR("Missing event name(s).\n");
 214                 usage(stderr);
 215                 ret = CMD_SUCCESS;
 216                 goto end;
 217         }
 218
 219         if (!opt_session_name) {
 220                 session_name = get_session_name();
 221                 if (session_name == NULL) {
 222                         ret = -1;
 223                         goto end;
 224                 }
 225         } else {
 226                 session_name = opt_session_name;
 227         }
 228
 229         ret = disable_events(session_name);
 230
 231 end:
 232         return ret;
 233 }