[lttng-tools.git] / src / bin / lttng / commands / enable_channels.c

/*
 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _GNU_SOURCE
#include <popt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <inttypes.h>

#include "../command.h"

#include <src/common/sessiond-comm/sessiond-comm.h>

static char *opt_channels;
static int opt_kernel;
static char *opt_session_name;
static int opt_userspace;
static struct lttng_channel chan;
static char *opt_output;
#if 0
/* Not implemented yet */
static char *opt_cmd_name;
static pid_t opt_pid;
#endif

enum {
	OPT_HELP = 1,
	OPT_DISCARD,
	OPT_OVERWRITE,
	OPT_SUBBUF_SIZE,
	OPT_NUM_SUBBUF,
	OPT_SWITCH_TIMER,
	OPT_READ_TIMER,
	OPT_USERSPACE,
	OPT_LIST_OPTIONS,
};

static struct lttng_handle *handle;

const char *output_mmap = "mmap";
const char *output_splice = "splice";

static struct poptOption long_options[] = {
	/* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
	{"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
	{"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
	{"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
#if 0
	/* Not implemented yet */
	{"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
	{"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
#else
	{"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
#endif
	{"discard",        0,   POPT_ARG_NONE, 0, OPT_DISCARD, 0, 0},
	{"overwrite",      0,   POPT_ARG_NONE, 0, OPT_OVERWRITE, 0, 0},
	{"subbuf-size",    0,   POPT_ARG_DOUBLE, 0, OPT_SUBBUF_SIZE, 0, 0},
	{"num-subbuf",     0,   POPT_ARG_INT, 0, OPT_NUM_SUBBUF, 0, 0},
	{"switch-timer",   0,   POPT_ARG_INT, 0, OPT_SWITCH_TIMER, 0, 0},
	{"read-timer",     0,   POPT_ARG_INT, 0, OPT_READ_TIMER, 0, 0},
	{"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
	{"output",         0,   POPT_ARG_STRING, &opt_output, 0, 0, 0},
	{0, 0, 0, 0, 0, 0, 0}
};

/*
 * usage
 */
static void usage(FILE *ofp)
{
	fprintf(ofp, "usage: lttng enable-channel NAME[,NAME2,...] [-u|-k] [OPTIONS]\n");
	fprintf(ofp, "\n");
	fprintf(ofp, "Options:\n");
	fprintf(ofp, "  -h, --help               Show this help\n");
	fprintf(ofp, "      --list-options       Simple listing of options\n");
	fprintf(ofp, "  -s, --session NAME       Apply to session name\n");
	fprintf(ofp, "  -k, --kernel             Apply to the kernel tracer\n");
	fprintf(ofp, "  -u, --userspace          Apply to the user-space tracer\n");
	fprintf(ofp, "\n");
	fprintf(ofp, "Channel options:\n");
	fprintf(ofp, "      --discard            Discard event when buffers are full%s\n",
		DEFAULT_CHANNEL_OVERWRITE ? "" : " (default)");
	fprintf(ofp, "      --overwrite          Flight recorder mode%s\n",
		DEFAULT_CHANNEL_OVERWRITE ? " (default)" : "");
	fprintf(ofp, "      --subbuf-size SIZE   Subbuffer size in bytes\n");
	fprintf(ofp, "                               (default: %u, kernel default: %u)\n",
		DEFAULT_CHANNEL_SUBBUF_SIZE,
		DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE);
	fprintf(ofp, "                               Needs to be a power of 2 for\n");
        fprintf(ofp, "                               kernel and ust tracers\n");
	fprintf(ofp, "      --num-subbuf NUM     Number of subbufers\n");
	fprintf(ofp, "                               (default: %u)\n",
		DEFAULT_CHANNEL_SUBBUF_NUM);
	fprintf(ofp, "                               Needs to be a power of 2 for\n");
        fprintf(ofp, "                               kernel and ust tracers\n");
	fprintf(ofp, "      --switch-timer USEC  Switch timer interval in usec (default: %u)\n",
		DEFAULT_CHANNEL_SWITCH_TIMER);
	fprintf(ofp, "      --read-timer USEC    Read timer interval in usec (default: %u)\n",
		DEFAULT_CHANNEL_READ_TIMER);
	fprintf(ofp, "      --output TYPE        Channel output type (Values: %s, %s)\n",
			output_mmap, output_splice);
	fprintf(ofp, "\n");
}

/*
 * Set default attributes depending on those already defined from the command
 * line.
 */
static void set_default_attr(struct lttng_domain *dom)
{
	struct lttng_channel_attr default_attr;

	/* Set attributes */
	lttng_channel_set_default_attr(dom, &default_attr);

	if (chan.attr.overwrite == -1) {
		chan.attr.overwrite = default_attr.overwrite;
	}
	if (chan.attr.subbuf_size == -1) {
		chan.attr.subbuf_size = default_attr.subbuf_size;
	}
	if (chan.attr.num_subbuf == -1) {
		chan.attr.num_subbuf = default_attr.num_subbuf;
	}
	if (chan.attr.switch_timer_interval == -1) {
		chan.attr.switch_timer_interval = default_attr.switch_timer_interval;
	}
	if (chan.attr.read_timer_interval == -1) {
		chan.attr.read_timer_interval = default_attr.read_timer_interval;
	}
	if (chan.attr.output == -1) {
		chan.attr.output = default_attr.output;
	}
}

/*
 * Adding channel using the lttng API.
 */
static int enable_channel(char *session_name)
{
	int ret = CMD_SUCCESS, warn = 0;
	char *channel_name;
	struct lttng_domain dom;

	memset(&dom, 0, sizeof(dom));

	/* Create lttng domain */
	if (opt_kernel) {
		dom.type = LTTNG_DOMAIN_KERNEL;
	} else if (opt_userspace) {
		dom.type = LTTNG_DOMAIN_UST;
	} else {
		ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
		ret = CMD_ERROR;
		goto error;
	}

	set_default_attr(&dom);

	/* Setting channel output */
	if (opt_output) {
		if (!strncmp(output_mmap, opt_output, strlen(output_mmap))) {
			chan.attr.output = LTTNG_EVENT_MMAP;
		} else if (!strncmp(output_splice, opt_output, strlen(output_splice))) {
			chan.attr.output = LTTNG_EVENT_SPLICE;
		} else {
			ERR("Unknown output type %s. Possible values are: %s, %s\n",
					opt_output, output_mmap, output_splice);
			usage(stderr);
			ret = CMD_ERROR;
			goto error;
		}
	}

	handle = lttng_create_handle(session_name, &dom);
	if (handle == NULL) {
		ret = -1;
		goto error;
	}

	/* Strip channel list (format: chan1,chan2,...) */
	channel_name = strtok(opt_channels, ",");
	while (channel_name != NULL) {
		/* Copy channel name and normalize it */
		strncpy(chan.name, channel_name, NAME_MAX);
		chan.name[NAME_MAX - 1] = '\0';

		DBG("Enabling channel %s", channel_name);

		ret = lttng_enable_channel(handle, &chan);
		if (ret < 0) {
			switch (-ret) {
			case LTTNG_ERR_KERN_CHAN_EXIST:
			case LTTNG_ERR_UST_CHAN_EXIST:
				WARN("Channel %s: %s (session %s", channel_name,
						lttng_strerror(ret), session_name);
				goto error;
			default:
				ERR("Channel %s: %s (session %s)", channel_name,
						lttng_strerror(ret), session_name);
				break;
			}
			warn = 1;
		} else {
			MSG("%s channel %s enabled for session %s",
					opt_kernel ? "Kernel" : "UST", channel_name,
					session_name);
		}

		/* Next event */
		channel_name = strtok(NULL, ",");
	}

	ret = CMD_SUCCESS;

error:
	if (warn) {
		ret = CMD_WARNING;
	}

	lttng_destroy_handle(handle);

	return ret;
}

/*
 * Default value for channel configuration.
 */
static void init_channel_config(void)
{
	/*
	 * Put -1 everywhere so we can identify those set by the command line and
	 * those needed to be set by the default values.
	 */
	memset(&chan.attr, -1, sizeof(chan.attr));
}

/*
 * Add channel to trace session
 */
int cmd_enable_channels(int argc, const char **argv)
{
	int opt, ret = CMD_SUCCESS;
	static poptContext pc;
	char *session_name = NULL;

	init_channel_config();

	pc = poptGetContext(NULL, argc, argv, long_options, 0);
	poptReadDefaultConfig(pc, 0);

	while ((opt = poptGetNextOpt(pc)) != -1) {
		switch (opt) {
		case OPT_HELP:
			usage(stdout);
			goto end;
		case OPT_DISCARD:
			chan.attr.overwrite = 0;
			DBG("Channel set to discard");
			break;
		case OPT_OVERWRITE:
			chan.attr.overwrite = 1;
			DBG("Channel set to overwrite");
			break;
		case OPT_SUBBUF_SIZE:
			/* TODO Replace atol with strtol and check for errors */
			chan.attr.subbuf_size = atol(poptGetOptArg(pc));
			DBG("Channel subbuf size set to %" PRIu64, chan.attr.subbuf_size);
			break;
		case OPT_NUM_SUBBUF:
			/* TODO Replace atoi with strtol and check for errors */
			chan.attr.num_subbuf = atoi(poptGetOptArg(pc));
			DBG("Channel subbuf num set to %" PRIu64, chan.attr.num_subbuf);
			break;
		case OPT_SWITCH_TIMER:
			/* TODO Replace atoi with strtol and check for errors */
			chan.attr.switch_timer_interval = atoi(poptGetOptArg(pc));
			DBG("Channel switch timer interval set to %d", chan.attr.switch_timer_interval);
			break;
		case OPT_READ_TIMER:
			/* TODO Replace atoi with strtol and check for errors */
			chan.attr.read_timer_interval = atoi(poptGetOptArg(pc));
			DBG("Channel read timer interval set to %d", chan.attr.read_timer_interval);
			break;
		case OPT_USERSPACE:
			opt_userspace = 1;
			break;
		case OPT_LIST_OPTIONS:
			list_cmd_options(stdout, long_options);
			goto end;
		default:
			usage(stderr);
			ret = CMD_UNDEFINED;
			goto end;
		}
	}

	opt_channels = (char*) poptGetArg(pc);
	if (opt_channels == NULL) {
		ERR("Missing channel name.\n");
		usage(stderr);
		ret = CMD_ERROR;
		goto end;
	}

	if (!opt_session_name) {
		session_name = get_session_name();
		if (session_name == NULL) {
			ret = CMD_ERROR;
			goto end;
		}
	} else {
		session_name = opt_session_name;
	}

	ret = enable_channel(session_name);

end:
	if (!opt_session_name && session_name) {
		free(session_name);
	}
	poptFreeContext(pc);
	return ret;
}
Commit	Line	Data
d36b8583 DG	1	/*
	2	* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
	3	*
d14d33bf AM	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2 only,
	6	* as published by the Free Software Foundation.
d36b8583 DG	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
d14d33bf AM	13	* You should have received a copy of the GNU General Public License along
	14	* with this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
d36b8583 DG	16	*/
	17
	18	#define _GNU_SOURCE
	19	#include <popt.h>
	20	#include <stdio.h>
	21	#include <stdlib.h>
	22	#include <string.h>
	23	#include <sys/stat.h>
	24	#include <sys/types.h>
	25	#include <unistd.h>
5a0de755	26	#include <inttypes.h>
d36b8583	27
c399183f	28	#include "../command.h"
d36b8583	29
42224349 DG	30	#include <src/common/sessiond-comm/sessiond-comm.h>
42224349 DG	31
d36b8583	32	static char *opt_channels;
5edd7e09	33	static int opt_kernel;
5440dc42	34	static char *opt_session_name;
d36b8583	35	static int opt_userspace;
d78d6610	36	static struct lttng_channel chan;
a79d84dd	37	static char *opt_output;
d78d6610 DG	38	#if 0
d78d6610 DG	39	/* Not implemented yet */
eeac7d46	40	static char *opt_cmd_name;
d36b8583	41	static pid_t opt_pid;
d78d6610	42	#endif
d36b8583 DG	43
	44	enum {
	45	OPT_HELP = 1,
7d29a247 DG	46	OPT_DISCARD,
	47	OPT_OVERWRITE,
	48	OPT_SUBBUF_SIZE,
	49	OPT_NUM_SUBBUF,
	50	OPT_SWITCH_TIMER,
	51	OPT_READ_TIMER,
d36b8583	52	OPT_USERSPACE,
679b4943	53	OPT_LIST_OPTIONS,
d36b8583 DG	54	};
d36b8583 DG	55
cd80958d DG	56	static struct lttng_handle *handle;
cd80958d DG	57
a79d84dd DG	58	const char *output_mmap = "mmap";
	59	const char *output_splice = "splice";
	60
d36b8583 DG	61	static struct poptOption long_options[] = {
	62	/* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
	63	{"help", 'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
5440dc42	64	{"session", 's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
d36b8583	65	{"kernel", 'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
d78d6610 DG	66	#if 0
d78d6610 DG	67	/* Not implemented yet */
6caa2bcc	68	{"userspace", 'u', POPT_ARG_STRING \| POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
d36b8583	69	{"pid", 'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
d78d6610 DG	70	#else
	71	{"userspace", 'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
	72	#endif
7d29a247 DG	73	{"discard", 0, POPT_ARG_NONE, 0, OPT_DISCARD, 0, 0},
7d29a247 DG	74	{"overwrite", 0, POPT_ARG_NONE, 0, OPT_OVERWRITE, 0, 0},
1b579521 DG	75	{"subbuf-size", 0, POPT_ARG_DOUBLE, 0, OPT_SUBBUF_SIZE, 0, 0},
	76	{"num-subbuf", 0, POPT_ARG_INT, 0, OPT_NUM_SUBBUF, 0, 0},
	77	{"switch-timer", 0, POPT_ARG_INT, 0, OPT_SWITCH_TIMER, 0, 0},
	78	{"read-timer", 0, POPT_ARG_INT, 0, OPT_READ_TIMER, 0, 0},
679b4943	79	{"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
a79d84dd	80	{"output", 0, POPT_ARG_STRING, &opt_output, 0, 0, 0},
d36b8583 DG	81	{0, 0, 0, 0, 0, 0, 0}
	82	};
	83
	84	/*
	85	* usage
	86	*/
	87	static void usage(FILE *ofp)
	88	{
32a6298d	89	fprintf(ofp, "usage: lttng enable-channel NAME[,NAME2,...] [-u\|-k] [OPTIONS]\n");
d36b8583	90	fprintf(ofp, "\n");
32a6298d	91	fprintf(ofp, "Options:\n");
7d29a247	92	fprintf(ofp, " -h, --help Show this help\n");
679b4943	93	fprintf(ofp, " --list-options Simple listing of options\n");
32a6298d	94	fprintf(ofp, " -s, --session NAME Apply to session name\n");
27221701	95	fprintf(ofp, " -k, --kernel Apply to the kernel tracer\n");
27221701	96	fprintf(ofp, " -u, --userspace Apply to the user-space tracer\n");
7d29a247 DG	97	fprintf(ofp, "\n");
7d29a247 DG	98	fprintf(ofp, "Channel options:\n");
cabd9892 MD	99	fprintf(ofp, " --discard Discard event when buffers are full%s\n",
	100	DEFAULT_CHANNEL_OVERWRITE ? "" : " (default)");
	101	fprintf(ofp, " --overwrite Flight recorder mode%s\n",
	102	DEFAULT_CHANNEL_OVERWRITE ? " (default)" : "");
cc62c0c0	103	fprintf(ofp, " --subbuf-size SIZE Subbuffer size in bytes\n");
cabd9892 MD	104	fprintf(ofp, " (default: %u, kernel default: %u)\n",
	105	DEFAULT_CHANNEL_SUBBUF_SIZE,
	106	DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE);
93e6c8a0 MD	107	fprintf(ofp, " Needs to be a power of 2 for\n");
93e6c8a0 MD	108	fprintf(ofp, " kernel and ust tracers\n");
cc62c0c0	109	fprintf(ofp, " --num-subbuf NUM Number of subbufers\n");
9f778c9a MD	110	fprintf(ofp, " (default: %u)\n",
9f778c9a MD	111	DEFAULT_CHANNEL_SUBBUF_NUM);
93e6c8a0 MD	112	fprintf(ofp, " Needs to be a power of 2 for\n");
93e6c8a0 MD	113	fprintf(ofp, " kernel and ust tracers\n");
cc62c0c0	114	fprintf(ofp, " --switch-timer USEC Switch timer interval in usec (default: %u)\n",
cabd9892	115	DEFAULT_CHANNEL_SWITCH_TIMER);
cc62c0c0	116	fprintf(ofp, " --read-timer USEC Read timer interval in usec (default: %u)\n",
cabd9892	117	DEFAULT_CHANNEL_READ_TIMER);
a79d84dd DG	118	fprintf(ofp, " --output TYPE Channel output type (Values: %s, %s)\n",
a79d84dd DG	119	output_mmap, output_splice);
d36b8583 DG	120	fprintf(ofp, "\n");
	121	}
	122
5edd7e09 DG	123	/*
	124	* Set default attributes depending on those already defined from the command
	125	* line.
	126	*/
	127	static void set_default_attr(struct lttng_domain *dom)
	128	{
	129	struct lttng_channel_attr default_attr;
	130
	131	/* Set attributes */
	132	lttng_channel_set_default_attr(dom, &default_attr);
	133
	134	if (chan.attr.overwrite == -1) {
	135	chan.attr.overwrite = default_attr.overwrite;
	136	}
	137	if (chan.attr.subbuf_size == -1) {
	138	chan.attr.subbuf_size = default_attr.subbuf_size;
	139	}
	140	if (chan.attr.num_subbuf == -1) {
	141	chan.attr.num_subbuf = default_attr.num_subbuf;
	142	}
	143	if (chan.attr.switch_timer_interval == -1) {
	144	chan.attr.switch_timer_interval = default_attr.switch_timer_interval;
	145	}
	146	if (chan.attr.read_timer_interval == -1) {
	147	chan.attr.read_timer_interval = default_attr.read_timer_interval;
	148	}
	149	if (chan.attr.output == -1) {
	150	chan.attr.output = default_attr.output;
	151	}
	152	}
	153
d36b8583	154	/*
0fdd1e2c	155	* Adding channel using the lttng API.
d36b8583	156	*/
cd80958d	157	static int enable_channel(char *session_name)
d36b8583	158	{
ae856491	159	int ret = CMD_SUCCESS, warn = 0;
d36b8583	160	char *channel_name;
7d29a247	161	struct lttng_domain dom;
d36b8583	162
441c16a7 MD	163	memset(&dom, 0, sizeof(dom));
441c16a7 MD	164
d78d6610	165	/* Create lttng domain */
7d29a247 DG	166	if (opt_kernel) {
7d29a247 DG	167	dom.type = LTTNG_DOMAIN_KERNEL;
d78d6610	168	} else if (opt_userspace) {
f6a9efaa	169	dom.type = LTTNG_DOMAIN_UST;
0fdd1e2c	170	} else {
e14f64a8	171	ERR("Please specify a tracer (-k/--kernel or -u/--userspace)");
d16c1a4c	172	ret = CMD_ERROR;
0fdd1e2c	173	goto error;
7d29a247 DG	174	}
7d29a247 DG	175
5edd7e09 DG	176	set_default_attr(&dom);
5edd7e09 DG	177
a79d84dd DG	178	/* Setting channel output */
	179	if (opt_output) {
	180	if (!strncmp(output_mmap, opt_output, strlen(output_mmap))) {
	181	chan.attr.output = LTTNG_EVENT_MMAP;
	182	} else if (!strncmp(output_splice, opt_output, strlen(output_splice))) {
	183	chan.attr.output = LTTNG_EVENT_SPLICE;
	184	} else {
	185	ERR("Unknown output type %s. Possible values are: %s, %s\n",
	186	opt_output, output_mmap, output_splice);
	187	usage(stderr);
	188	ret = CMD_ERROR;
	189	goto error;
	190	}
	191	}
	192
cd80958d DG	193	handle = lttng_create_handle(session_name, &dom);
	194	if (handle == NULL) {
	195	ret = -1;
	196	goto error;
	197	}
	198
0fdd1e2c	199	/* Strip channel list (format: chan1,chan2,...) */
d36b8583 DG	200	channel_name = strtok(opt_channels, ",");
d36b8583 DG	201	while (channel_name != NULL) {
0fdd1e2c DG	202	/* Copy channel name and normalize it */
	203	strncpy(chan.name, channel_name, NAME_MAX);
	204	chan.name[NAME_MAX - 1] = '\0';
	205
	206	DBG("Enabling channel %s", channel_name);
	207
	208	ret = lttng_enable_channel(handle, &chan);
	209	if (ret < 0) {
42224349	210	switch (-ret) {
f73fabfd DG	211	case LTTNG_ERR_KERN_CHAN_EXIST:
f73fabfd DG	212	case LTTNG_ERR_UST_CHAN_EXIST:
42224349 DG	213	WARN("Channel %s: %s (session %s", channel_name,
	214	lttng_strerror(ret), session_name);
	215	goto error;
	216	default:
	217	ERR("Channel %s: %s (session %s)", channel_name,
	218	lttng_strerror(ret), session_name);
	219	break;
	220	}
ae856491	221	warn = 1;
d36b8583	222	} else {
7885e399 DG	223	MSG("%s channel %s enabled for session %s",
	224	opt_kernel ? "Kernel" : "UST", channel_name,
	225	session_name);
d36b8583 DG	226	}
	227
	228	/* Next event */
	229	channel_name = strtok(NULL, ",");
	230	}
	231
ae856491 DG	232	ret = CMD_SUCCESS;
ae856491 DG	233
d36b8583	234	error:
ae856491 DG	235	if (warn) {
	236	ret = CMD_WARNING;
	237	}
	238
cd80958d DG	239	lttng_destroy_handle(handle);
cd80958d DG	240
d36b8583 DG	241	return ret;
	242	}
	243
	244	/*
0fdd1e2c	245	* Default value for channel configuration.
7d29a247 DG	246	*/
	247	static void init_channel_config(void)
	248	{
5edd7e09 DG	249	/*
	250	* Put -1 everywhere so we can identify those set by the command line and
	251	* those needed to be set by the default values.
	252	*/
	253	memset(&chan.attr, -1, sizeof(chan.attr));
7d29a247 DG	254	}
	255
	256	/*
0fdd1e2c	257	* Add channel to trace session
d36b8583 DG	258	*/
	259	int cmd_enable_channels(int argc, const char **argv)
	260	{
ca1c3607	261	int opt, ret = CMD_SUCCESS;
d36b8583	262	static poptContext pc;
cd80958d	263	char *session_name = NULL;
d36b8583	264
7d29a247 DG	265	init_channel_config();
7d29a247 DG	266
d36b8583 DG	267	pc = poptGetContext(NULL, argc, argv, long_options, 0);
	268	poptReadDefaultConfig(pc, 0);
	269
	270	while ((opt = poptGetNextOpt(pc)) != -1) {
	271	switch (opt) {
	272	case OPT_HELP:
ca1c3607	273	usage(stdout);
d36b8583	274	goto end;
7d29a247 DG	275	case OPT_DISCARD:
	276	chan.attr.overwrite = 0;
	277	DBG("Channel set to discard");
	278	break;
	279	case OPT_OVERWRITE:
	280	chan.attr.overwrite = 1;
	281	DBG("Channel set to overwrite");
	282	break;
	283	case OPT_SUBBUF_SIZE:
ca1c3607	284	/* TODO Replace atol with strtol and check for errors */
7d29a247	285	chan.attr.subbuf_size = atol(poptGetOptArg(pc));
5a0de755	286	DBG("Channel subbuf size set to %" PRIu64, chan.attr.subbuf_size);
7d29a247 DG	287	break;
7d29a247 DG	288	case OPT_NUM_SUBBUF:
ca1c3607	289	/* TODO Replace atoi with strtol and check for errors */
7d29a247	290	chan.attr.num_subbuf = atoi(poptGetOptArg(pc));
5a0de755	291	DBG("Channel subbuf num set to %" PRIu64, chan.attr.num_subbuf);
7d29a247 DG	292	break;
7d29a247 DG	293	case OPT_SWITCH_TIMER:
ca1c3607	294	/* TODO Replace atoi with strtol and check for errors */
7d29a247 DG	295	chan.attr.switch_timer_interval = atoi(poptGetOptArg(pc));
	296	DBG("Channel switch timer interval set to %d", chan.attr.switch_timer_interval);
	297	break;
	298	case OPT_READ_TIMER:
ca1c3607	299	/* TODO Replace atoi with strtol and check for errors */
7d29a247 DG	300	chan.attr.read_timer_interval = atoi(poptGetOptArg(pc));
7d29a247 DG	301	DBG("Channel read timer interval set to %d", chan.attr.read_timer_interval);
d36b8583	302	break;
eeac7d46 MD	303	case OPT_USERSPACE:
eeac7d46 MD	304	opt_userspace = 1;
eeac7d46	305	break;
679b4943 SM	306	case OPT_LIST_OPTIONS:
679b4943 SM	307	list_cmd_options(stdout, long_options);
679b4943	308	goto end;
d36b8583 DG	309	default:
	310	usage(stderr);
	311	ret = CMD_UNDEFINED;
	312	goto end;
	313	}
	314	}
	315
	316	opt_channels = (char*) poptGetArg(pc);
	317	if (opt_channels == NULL) {
7d29a247	318	ERR("Missing channel name.\n");
d36b8583	319	usage(stderr);
ca1c3607	320	ret = CMD_ERROR;
d36b8583 DG	321	goto end;
	322	}
	323
cd80958d DG	324	if (!opt_session_name) {
	325	session_name = get_session_name();
	326	if (session_name == NULL) {
ca1c3607	327	ret = CMD_ERROR;
cd80958d DG	328	goto end;
	329	}
	330	} else {
	331	session_name = opt_session_name;
	332	}
	333
	334	ret = enable_channel(session_name);
d36b8583 DG	335
d36b8583 DG	336	end:
5853fd43 DG	337	if (!opt_session_name && session_name) {
	338	free(session_name);
	339	}
ca1c3607	340	poptFreeContext(pc);
d36b8583 DG	341	return ret;
d36b8583 DG	342	}