lttng/commands/disable_channels.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_channels;
  33 static int opt_kernel;
  34 static char *opt_session_name;
  35 static int opt_userspace;
  36 static char *opt_cmd_name;
  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         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  51         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  52         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  53         {0, 0, 0, 0, 0, 0, 0}
  54 };
  55
  56 /*
  57  * usage
  58  */
  59 static void usage(FILE *ofp)
  60 {
  61         fprintf(ofp, "usage: lttng disable-channel NAME[,NAME2,...] [options]\n");
  62         fprintf(ofp, "\n");
  63         fprintf(ofp, "  -h, --help               Show this help\n");
  64         fprintf(ofp, "  -s, --session            Apply on session name\n");
  65         fprintf(ofp, "  -k, --kernel             Apply for the kernel tracer\n");
  66         fprintf(ofp, "  -u, --userspace [CMD]    Apply for the user-space tracer\n");
  67         fprintf(ofp, "                           If no CMD, the domain used is UST global\n");
  68         fprintf(ofp, "                           or else the domain is UST EXEC_NAME\n");
  69         fprintf(ofp, "  -p, --pid PID            If -u, apply to specific PID (domain: UST PID)\n");
  70         fprintf(ofp, "\n");
  71 }
  72
  73 /*
  74  * Disabling channel using the lttng API.
  75  */
  76 static int disable_channels(char *session_name)
  77 {
  78         int ret = CMD_SUCCESS;
  79         char *channel_name;
  80         struct lttng_domain dom;
  81
  82         if (opt_kernel) {
  83                 dom.type = LTTNG_DOMAIN_KERNEL;
  84         } else if (opt_pid != 0) {
  85                 dom.type = LTTNG_DOMAIN_UST_PID;
  86                 dom.attr.pid = opt_pid;
  87                 DBG("PID %d set to lttng handle", opt_pid);
  88         } else if (opt_userspace && opt_cmd_name == NULL) {
  89                 dom.type = LTTNG_DOMAIN_UST;
  90         } else if (opt_userspace && opt_cmd_name != NULL) {
  91                 dom.type = LTTNG_DOMAIN_UST_EXEC_NAME;
  92                 strncpy(dom.attr.exec_name, opt_cmd_name, NAME_MAX);
  93         } else {
  94                 ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
  95                 ret = CMD_NOT_IMPLEMENTED;
  96                 goto error;
  97         }
  98
  99         handle = lttng_create_handle(session_name, &dom);
 100         if (handle == NULL) {
 101                 ret = -1;
 102                 goto error;
 103         }
 104
 105         /* Strip channel list */
 106         channel_name = strtok(opt_channels, ",");
 107         while (channel_name != NULL) {
 108                 DBG("Disabling channel %s", channel_name);
 109
 110                 ret = lttng_disable_channel(handle, channel_name);
 111                 if (ret < 0) {
 112                         goto error;
 113                 } else {
 114                         MSG("Channel %s disabled for session %s", channel_name,
 115                                         session_name);
 116                 }
 117
 118                 /* Next channel */
 119                 channel_name = strtok(NULL, ",");
 120         }
 121
 122 error:
 123         lttng_destroy_handle(handle);
 124
 125         return ret;
 126 }
 127
 128 /*
 129  *  cmd_disable_channels
 130  *
 131  *  Disable channel to trace session
 132  */
 133 int cmd_disable_channels(int argc, const char **argv)
 134 {
 135         int opt, ret;
 136         static poptContext pc;
 137         char *session_name = NULL;
 138
 139         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 140         poptReadDefaultConfig(pc, 0);
 141
 142         while ((opt = poptGetNextOpt(pc)) != -1) {
 143                 switch (opt) {
 144                 case OPT_HELP:
 145                         usage(stderr);
 146                         ret = CMD_SUCCESS;
 147                         goto end;
 148                 case OPT_USERSPACE:
 149                         opt_userspace = 1;
 150                         break;
 151                 default:
 152                         usage(stderr);
 153                         ret = CMD_UNDEFINED;
 154                         goto end;
 155                 }
 156         }
 157
 158         opt_channels = (char*) poptGetArg(pc);
 159         if (opt_channels == NULL) {
 160                 ERR("Missing channel name(s).\n");
 161                 usage(stderr);
 162                 ret = CMD_SUCCESS;
 163                 goto end;
 164         }
 165
 166         if (!opt_session_name) {
 167                 session_name = get_session_name();
 168                 if (session_name == NULL) {
 169                         ret = -1;
 170                         goto end;
 171                 }
 172         } else {
 173                 session_name = opt_session_name;
 174         }
 175
 176         ret = disable_channels(session_name);
 177
 178 end:
 179         return ret;
 180 }