X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng%2Fcommands%2Ftrack-untrack.c;h=e796aa97c448da5ebde65f908b4456a56dbb680a;hp=154501e597ab56a6de266447be1f6c995235efc3;hb=d89dd55ea0f25f8b3fafd064fd887759c9a05af0;hpb=5cfbc08ca9e36ca0d5cac64e2c448cdb5cb863a7

diff --git a/src/bin/lttng/commands/track-untrack.c b/src/bin/lttng/commands/track-untrack.c
index 154501e59..e796aa97c 100644
--- a/src/bin/lttng/commands/track-untrack.c
+++ b/src/bin/lttng/commands/track-untrack.c
@@ -1,24 +1,16 @@
 /*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
- * 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.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * 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 _LGPL_SOURCE
 #include <ctype.h>
 #include <popt.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -29,305 +21,571 @@
 
 #include <urcu/list.h>
 
+#include <common/dynamic-array.h>
 #include <common/mi-lttng.h>
+#include <common/optional.h>
+#include <common/dynamic-buffer.h>
+#include <common/tracker.h>
+
+#include <lttng/lttng.h>
 
 #include "../command.h"
 
+struct process_attr_command_args {
+	enum lttng_process_attr process_attr;
+	/* Present in the user's command. */
+	bool requested;
+	bool all;
+	struct lttng_dynamic_pointer_array string_args;
+};
+
 enum cmd_type {
 	CMD_TRACK,
 	CMD_UNTRACK,
 };
 
-static char *opt_session_name;
-static int opt_kernel;
-static int opt_userspace;
-static int opt_all;
-static char *opt_pid_string;
-static int opt_pid;
-
+/* Offset OPT_ values by one since libpopt gives '0' a special meaning. */
 enum {
-	OPT_HELP = 1,
+	OPT_PID = LTTNG_PROCESS_ATTR_PROCESS_ID + 1,
+	OPT_VPID = LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID + 1,
+	OPT_UID = LTTNG_PROCESS_ATTR_USER_ID + 1,
+	OPT_VUID = LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID + 1,
+	OPT_GID = LTTNG_PROCESS_ATTR_GROUP_ID + 1,
+	OPT_VGID = LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID + 1,
+	OPT_HELP,
 	OPT_LIST_OPTIONS,
 	OPT_SESSION,
-	OPT_PID,
+	OPT_ALL,
 };
 
+static char *opt_session_name;
+static int opt_kernel;
+static int opt_userspace;
+static char *opt_str_arg;
+
 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, OPT_SESSION, 0, 0, },
 	{ "kernel",		'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0, },
 	{ "userspace",		'u', POPT_ARG_VAL, &opt_userspace, 1, 0, 0, },
-	{ "pid",		'p', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_pid_string, OPT_PID, 0, 0, },
-	{ "all",		'a', POPT_ARG_VAL, &opt_all, 1, 0, 0, },
+	{ "pid",		'p', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_PID, 0, 0, },
+	{ "vpid",		0, POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_VPID, 0, 0, },
+	{ "uid",		0, POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_UID, 0, 0, },
+	{ "vuid",		0, POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_VUID, 0, 0, },
+	{ "gid",		0, POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_GID, 0, 0, },
+	{ "vgid",		0, POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_str_arg, OPT_VGID, 0, 0, },
+	{ "all",		'a', POPT_ARG_NONE, 0, OPT_ALL, 0, 0, },
 	{ "list-options",	0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, 0, 0, },
 	{ 0, 0, 0, 0, 0, 0, 0, },
 };
 
-static
-int parse_pid_string(const char *_pid_string,
-		int all, int **_pid_list, int *nr_pids)
-{
-	const char *one_pid_str;
-	char *iter;
-	int retval = CMD_SUCCESS;
-	int count = 0;
-	int *pid_list = NULL;
-	char *pid_string = NULL;
-	char *endptr;
-
-	if (all && _pid_string) {
-		ERR("An empty PID string is expected with --all");
-		retval = CMD_ERROR;
-		goto error;
-	}
-	if (!all && !_pid_string) {
-		ERR("Please specify --all with an empty PID string");
-		retval = CMD_ERROR;
-		goto error;
-	}
-	if (all) {
-		pid_list = zmalloc(sizeof(*pid_list));
-		if (!pid_list) {
-			ERR("Out of memory");
-			retval = CMD_ERROR;
-			goto error;
-		}
-		/* Empty PID string means all PIDs */
-		count = 1;
-		pid_list[0] = -1;
-		goto assign;
-	}
+static struct process_attr_command_args
+		process_attr_commands[LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID + 1];
 
-	pid_string = strdup(_pid_string);
-	if (!pid_string) {
-		ERR("Out of memory");
-		retval = CMD_ERROR;
-		goto error;
-	}
-
-	/* Count */
-	one_pid_str = strtok_r(pid_string, ",", &iter);
-	while (one_pid_str != NULL) {
-		unsigned long v;
-
-		errno = 0;
-		v = strtoul(one_pid_str, &endptr, 10);
-		if ((v == 0 && errno == EINVAL)
-				|| (v == ULONG_MAX && errno == ERANGE)
-				|| (*one_pid_str != '\0' && *endptr != '\0')){
-			ERR("Error parsing PID %s", one_pid_str);
-			retval = CMD_ERROR;
-			goto error;
-		}
+static void process_attr_command_init(struct process_attr_command_args *cmd,
+		enum lttng_process_attr process_attr)
+{
+	cmd->process_attr = process_attr;
+	cmd->all = false;
+	lttng_dynamic_pointer_array_init(&cmd->string_args, NULL);
+}
 
-		if ((long) v > INT_MAX || (int) v < 0) {
-			ERR("Invalid PID value %ld", (long) v);
-			retval = CMD_ERROR;
-			goto error;
-		}
-		count++;
+static void process_attr_command_fini(struct process_attr_command_args *cmd)
+{
+	lttng_dynamic_pointer_array_reset(&cmd->string_args);
+}
 
-		/* For next loop */
-		one_pid_str = strtok_r(NULL, ",", &iter);
+static const char *get_capitalized_process_attr_str(enum lttng_process_attr process_attr)
+{
+	switch (process_attr) {
+	case LTTNG_PROCESS_ATTR_PROCESS_ID:
+		return "Process ID";
+	case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+		return "Virtual process ID";
+	case LTTNG_PROCESS_ATTR_USER_ID:
+		return "User ID";
+	case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+		return "Virtual user ID";
+	case LTTNG_PROCESS_ATTR_GROUP_ID:
+		return "Group ID";
+	case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+		return "Virtual group ID";
+	default:
+		return "Unknown";
 	}
+	return NULL;
+}
 
-	free(pid_string);
-	/* Identity of delimiter has been lost in first pass. */
-	pid_string = strdup(_pid_string);
-	if (!pid_string) {
-		ERR("Out of memory");
-		retval = CMD_ERROR;
-		goto error;
+static bool ust_process_attr_supported(enum lttng_process_attr *process_attr)
+{
+	bool supported;
+
+	switch (*process_attr) {
+	case LTTNG_PROCESS_ATTR_PROCESS_ID:
+		*process_attr = LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID;
+		/* fall-through. */
+	case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+	case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+	case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+		supported = true;
+		break;
+	default:
+		ERR("The %s process attribute cannot be tracked in the user space domain.",
+				lttng_process_attr_to_string(*process_attr));
+		supported = false;
+		break;
 	}
+	return supported;
+}
 
-	/* Allocate */
-	pid_list = zmalloc(count * sizeof(*pid_list));
-	if (!pid_list) {
-		ERR("Out of memory");
-		retval = CMD_ERROR;
-		goto error;
+static const char *get_mi_element_command(enum cmd_type cmd_type)
+{
+	switch (cmd_type) {
+	case CMD_TRACK:
+		return mi_lttng_element_command_track;
+	case CMD_UNTRACK:
+		return mi_lttng_element_command_untrack;
+	default:
+		abort();
 	}
+}
 
-	/* Reparse string and populate the pid list. */
-	count = 0;
-	one_pid_str = strtok_r(pid_string, ",", &iter);
-	while (one_pid_str != NULL) {
-		unsigned long v;
-
-		v = strtoul(one_pid_str, NULL, 10);
-		pid_list[count++] = (int) v;
+static enum cmd_error_code run_command_all(enum cmd_type cmd_type,
+		const char *session_name,
+		enum lttng_domain_type domain_type,
+		enum lttng_process_attr process_attr,
+		struct mi_writer *writer)
+{
+	struct lttng_process_attr_tracker_handle *tracker_handle = NULL;
+	const enum lttng_error_code handle_ret_code =
+			lttng_session_get_tracker_handle(session_name,
+					domain_type, process_attr,
+					&tracker_handle);
+	enum cmd_error_code cmd_ret = CMD_SUCCESS;
+	enum lttng_process_attr_tracker_handle_status status;
 
-		/* For next loop */
-		one_pid_str = strtok_r(NULL, ",", &iter);
+	if (writer) {
+		const int ret = mi_lttng_all_process_attribute_value(
+				writer, process_attr, true);
+		if (ret) {
+			cmd_ret = CMD_FATAL;
+			goto end;
+		}
 	}
 
-assign:
-	*nr_pids = count;
-	*_pid_list = pid_list;
-	goto end;	/* SUCCESS */
-
-	/* ERROR */
-error:
-	free(pid_list);
-end:
-	free(pid_string);
-	return retval;
-}
-
-static
-enum cmd_error_code track_untrack_pid(enum cmd_type cmd_type, const char *cmd_str,
-		const char *session_name, const char *pid_string,
-		int all, struct mi_writer *writer)
-{
-	int ret, success = 1 , i;
-	enum cmd_error_code retval = CMD_SUCCESS;
-	int *pid_list = NULL;
-	int nr_pids;
-	struct lttng_domain dom;
-	struct lttng_handle *handle = NULL;
-	int (*cmd_func)(struct lttng_handle *handle, int pid);
+	if (handle_ret_code != LTTNG_OK) {
+		ERR("Session `%s` does not exist", session_name);
+		cmd_ret = CMD_FATAL;
+		goto end;
+	}
 
-	switch (cmd_type) {
-	case CMD_TRACK:
-		cmd_func = lttng_track_pid;
+	status = lttng_process_attr_tracker_handle_set_tracking_policy(
+			tracker_handle,
+			cmd_type == CMD_TRACK ?
+					LTTNG_TRACKING_POLICY_INCLUDE_ALL :
+					LTTNG_TRACKING_POLICY_EXCLUDE_ALL);
+	switch (status) {
+	case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
+		if (cmd_type == CMD_TRACK) {
+			MSG("%s tracking policy set to `include all`",
+					get_capitalized_process_attr_str(process_attr));
+		} else {
+			MSG("%s tracking policy set to `exclude all`",
+					get_capitalized_process_attr_str(process_attr));
+		}
 		break;
-	case CMD_UNTRACK:
-		cmd_func = lttng_untrack_pid;
+	case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_SESSION_DOES_NOT_EXIST:
+		ERR("%s", lttng_strerror(-LTTNG_ERR_SESS_NOT_FOUND));
 		break;
 	default:
-		ERR("Unknown command");
-		retval = CMD_ERROR;
-		goto end;
+		ERR("Unknown error encountered while setting tracking policy of %s tracker to `%s`",
+				lttng_process_attr_to_string(process_attr),
+				cmd_type == CMD_TRACK ? "include all" :
+							"exclude all");
+		cmd_ret = CMD_FATAL;
+		break;
 	}
+end:
+	if (writer) {
+		int ret = mi_lttng_writer_write_element_bool(writer,
+				mi_lttng_element_success,
+				cmd_ret == CMD_SUCCESS);
 
-	memset(&dom, 0, sizeof(dom));
-	if (opt_kernel) {
-		dom.type = LTTNG_DOMAIN_KERNEL;
-	} else if (opt_userspace) {
-		dom.type = LTTNG_DOMAIN_UST;
-	} else {
-		/* Checked by the caller. */
-		assert(0);
+		if (ret) {
+			cmd_ret = CMD_FATAL;
+		} else {
+			ret = mi_lttng_writer_close_element(writer);
+			cmd_ret = ret == 0 ? cmd_ret : CMD_FATAL;
+		}
 	}
+	lttng_process_attr_tracker_handle_destroy(tracker_handle);
+	return cmd_ret;
+}
 
-	ret = parse_pid_string(pid_string, all, &pid_list, &nr_pids);
-	if (ret != CMD_SUCCESS) {
-		ERR("Error parsing PID string");
-		retval = CMD_ERROR;
+static enum cmd_error_code run_command_string(enum cmd_type cmd_type,
+		const char *session_name,
+		enum lttng_domain_type domain_type,
+		enum lttng_process_attr process_attr,
+		const char *_args,
+		struct mi_writer *writer)
+{
+	struct lttng_process_attr_tracker_handle *tracker_handle;
+	const enum lttng_error_code handle_ret_code =
+			lttng_session_get_tracker_handle(session_name,
+					domain_type, process_attr,
+					&tracker_handle);
+	enum cmd_error_code cmd_ret = CMD_SUCCESS;
+	const char *one_value_str;
+	char *args = strdup(_args);
+	char *iter = args;
+	bool policy_set = false;
+
+	if (!args) {
+		ERR("%s", lttng_strerror(-LTTNG_ERR_NOMEM));
+		cmd_ret = CMD_FATAL;
 		goto end;
 	}
 
-	handle = lttng_create_handle(session_name, &dom);
-	if (handle == NULL) {
-		retval = CMD_ERROR;
+	if (handle_ret_code != LTTNG_OK) {
+		ERR("%s", lttng_strerror(-handle_ret_code));
+		cmd_ret = CMD_FATAL;
 		goto end;
 	}
 
-	if (writer) {
-		/* Open process element */
-		ret = mi_lttng_targets_open(writer);
-		if (ret) {
-			retval = CMD_ERROR;
-			goto end;
+	while ((one_value_str = strtok_r(iter, ",", &iter)) != NULL) {
+		const bool is_numerical_argument = isdigit(one_value_str[0]);
+		enum lttng_process_attr_tracker_handle_status status;
+		enum lttng_tracking_policy policy;
+		int ret;
+		char *prettified_arg;
+
+		if (!policy_set) {
+			status = lttng_process_attr_tracker_handle_get_tracking_policy(
+					tracker_handle, &policy);
+			if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
+				break;
+			}
+
+			if (policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
+				status = lttng_process_attr_tracker_handle_set_tracking_policy(
+						tracker_handle,
+						LTTNG_TRACKING_POLICY_INCLUDE_SET);
+				if (status != LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK) {
+					break;
+				}
+			}
+			policy_set = true;
 		}
-	}
 
-	for (i = 0; i < nr_pids; i++) {
-		DBG("%s PID %d", cmd_str, pid_list[i]);
-		ret = cmd_func(handle, pid_list[i]);
-		if (ret) {
-			switch (-ret) {
-			case LTTNG_ERR_PID_TRACKED:
-				WARN("PID %i already tracked in session %s",
-						pid_list[i], session_name);
-				success = 1;
-				retval = CMD_SUCCESS;
+		if (is_numerical_argument) {
+			const unsigned long one_value_int =
+					strtoul(one_value_str, NULL, 10);
+
+			if (writer) {
+				ret = mi_lttng_integral_process_attribute_value(
+						writer, process_attr,
+						(int64_t) one_value_int, true);
+				if (ret) {
+					cmd_ret = CMD_FATAL;
+					goto end;
+				}
+			}
+
+			switch (process_attr) {
+			case LTTNG_PROCESS_ATTR_PROCESS_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_process_id_tracker_handle_add_pid(
+									 tracker_handle,
+									 (pid_t) one_value_int) :
+							 lttng_process_attr_process_id_tracker_handle_remove_pid(
+									 tracker_handle,
+									 (pid_t) one_value_int);
 				break;
-			case LTTNG_ERR_PID_NOT_TRACKED:
-				WARN("PID %i not tracked in session %s",
-						pid_list[i], session_name);
-				success = 1;
-				retval = CMD_SUCCESS;
+			case LTTNG_PROCESS_ATTR_VIRTUAL_PROCESS_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_virtual_process_id_tracker_handle_add_pid(
+									 tracker_handle,
+									 (pid_t) one_value_int) :
+							 lttng_process_attr_virtual_process_id_tracker_handle_remove_pid(
+									 tracker_handle,
+									 (pid_t) one_value_int);
 				break;
-			default:
-				ERR("%s", lttng_strerror(ret));
-				success = 0;
-				retval = CMD_ERROR;
+			case LTTNG_PROCESS_ATTR_USER_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_user_id_tracker_handle_add_uid(
+									 tracker_handle,
+									 (uid_t) one_value_int) :
+							 lttng_process_attr_user_id_tracker_handle_remove_uid(
+									 tracker_handle,
+									 (uid_t) one_value_int);
+				break;
+			case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_virtual_user_id_tracker_handle_add_uid(
+									 tracker_handle,
+									 (uid_t) one_value_int) :
+							 lttng_process_attr_virtual_user_id_tracker_handle_remove_uid(
+									 tracker_handle,
+									 (uid_t) one_value_int);
 				break;
+			case LTTNG_PROCESS_ATTR_GROUP_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_group_id_tracker_handle_add_gid(
+									 tracker_handle,
+									 (gid_t) one_value_int) :
+							 lttng_process_attr_group_id_tracker_handle_remove_gid(
+									 tracker_handle,
+									 (gid_t) one_value_int);
+				break;
+			case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_virtual_group_id_tracker_handle_add_gid(
+									 tracker_handle,
+									 (gid_t) one_value_int) :
+							 lttng_process_attr_virtual_group_id_tracker_handle_remove_gid(
+									 tracker_handle,
+									 (gid_t) one_value_int);
+				break;
+			default:
+				abort();
 			}
+
 		} else {
-			MSG("PID %i %sed in session %s",
-					pid_list[i], cmd_str, session_name);
-			success = 1;
-		}
+			if (writer) {
+				ret = mi_lttng_string_process_attribute_value(
+						writer, process_attr,
+						one_value_str, true);
+				if (ret) {
+					cmd_ret = CMD_FATAL;
+					goto end;
+				}
+			}
 
-		/* Mi */
-		if (writer) {
-			ret = mi_lttng_pid_target(writer, pid_list[i], 1);
-			if (ret) {
-				retval = CMD_ERROR;
+			switch (process_attr) {
+			case LTTNG_PROCESS_ATTR_USER_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_user_id_tracker_handle_add_user_name(
+									 tracker_handle,
+									 one_value_str) :
+							 lttng_process_attr_user_id_tracker_handle_remove_user_name(
+									 tracker_handle,
+									 one_value_str);
+				break;
+			case LTTNG_PROCESS_ATTR_VIRTUAL_USER_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_virtual_user_id_tracker_handle_add_user_name(
+									 tracker_handle,
+									 one_value_str) :
+							 lttng_process_attr_virtual_user_id_tracker_handle_remove_user_name(
+									 tracker_handle,
+									 one_value_str);
+				break;
+			case LTTNG_PROCESS_ATTR_GROUP_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_group_id_tracker_handle_add_group_name(
+									 tracker_handle,
+									 one_value_str) :
+							 lttng_process_attr_group_id_tracker_handle_remove_group_name(
+									 tracker_handle,
+									 one_value_str);
+				break;
+			case LTTNG_PROCESS_ATTR_VIRTUAL_GROUP_ID:
+				status = cmd_type == CMD_TRACK ?
+							 lttng_process_attr_virtual_group_id_tracker_handle_add_group_name(
+									 tracker_handle,
+									 one_value_str) :
+							 lttng_process_attr_virtual_group_id_tracker_handle_remove_group_name(
+									 tracker_handle,
+									 one_value_str);
+				break;
+			default:
+				ERR("%s is not a valid %s value; expected an integer",
+						one_value_str,
+						lttng_process_attr_to_string(
+								process_attr));
+				cmd_ret = CMD_FATAL;
 				goto end;
 			}
+		}
 
-			ret = mi_lttng_writer_write_element_bool(writer,
-					mi_lttng_element_success, success);
-			if (ret) {
-				retval = CMD_ERROR;
-				goto end;
+		ret = asprintf(&prettified_arg,
+				is_numerical_argument ? "%s" : "`%s`",
+				one_value_str);
+		if (ret < 0) {
+			PERROR("Failed to format argument `%s`", one_value_str);
+			cmd_ret = CMD_FATAL;
+			goto end;
+		}
+
+		switch (status) {
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_OK:
+			if (cmd_type == CMD_TRACK) {
+				MSG("Added %s to the %s tracker inclusion set",
+						one_value_str,
+						lttng_process_attr_to_string(
+								process_attr));
+			} else {
+				MSG("Removed %s from the %s tracker inclusion set",
+						one_value_str,
+						lttng_process_attr_to_string(
+								process_attr));
 			}
+			break;
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_SESSION_DOES_NOT_EXIST:
+			ERR("Session `%s` not found", session_name);
+			break;
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_EXISTS:
+			WARN("%s is already in the %s inclusion set",
+					prettified_arg,
+					lttng_process_attr_to_string(
+							process_attr));
+			break;
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_MISSING:
+			WARN("%s is not in the %s the inclusion set",
+					prettified_arg,
+					lttng_process_attr_to_string(
+							process_attr));
+			break;
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_USER_NOT_FOUND:
+			ERR("User %s was not found", prettified_arg);
+			cmd_ret = CMD_ERROR;
+			break;
+		case LTTNG_PROCESS_ATTR_TRACKER_HANDLE_STATUS_GROUP_NOT_FOUND:
+			ERR("Group %s was not found", prettified_arg);
+			cmd_ret = CMD_ERROR;
+			break;
+		default:
+			ERR("Unknown error encountered while %s %s %s %s tracker's inclusion set",
+					cmd_type == CMD_TRACK ? "adding" :
+								"removing",
+					lttng_process_attr_to_string(
+							process_attr),
+					prettified_arg,
+					cmd_type == CMD_TRACK ? "to" : "from");
+			cmd_ret = CMD_FATAL;
+			break;
+		}
+		free(prettified_arg);
+
+		if (writer) {
+			ret = mi_lttng_writer_write_element_bool(writer,
+					mi_lttng_element_success,
+					cmd_ret == CMD_SUCCESS);
 
-			ret = mi_lttng_writer_close_element(writer);
 			if (ret) {
-				retval = CMD_ERROR;
-				goto end;
+				cmd_ret = CMD_FATAL;
+			} else {
+				ret = mi_lttng_writer_close_element(writer);
+				cmd_ret = ret == 0 ? cmd_ret : CMD_FATAL;
 			}
 		}
 	}
+end:
+	free(args);
+	lttng_process_attr_tracker_handle_destroy(tracker_handle);
+	return cmd_ret;
+}
+
+static enum cmd_error_code run_command(enum cmd_type cmd_type,
+		const char *session_name,
+		const struct process_attr_command_args *command_args,
+		struct mi_writer *writer)
+{
+	const enum lttng_domain_type domain_type =
+			opt_kernel ? LTTNG_DOMAIN_KERNEL : LTTNG_DOMAIN_UST;
+	enum cmd_error_code cmd_ret = CMD_SUCCESS;
+	unsigned int i;
+	const unsigned int string_arg_count =
+			lttng_dynamic_pointer_array_get_count(
+					&command_args->string_args);
+	enum lttng_process_attr process_attr = command_args->process_attr;
+
+	if (opt_userspace) {
+		/*
+		 * Check that this process attribute can be tracked
+		 * in the user space domain. Backward-compatibility
+		 * changes are be applied to process_attr as needed.
+		 */
+		if (!ust_process_attr_supported(&process_attr)) {
+			cmd_ret = CMD_ERROR;
+			goto end;
+		}
+	}
 
 	if (writer) {
-		/* Close targets element */
-		ret = mi_lttng_writer_close_element(writer);
+		/* Open tracker and trackers elements */
+		const int ret = mi_lttng_process_attribute_tracker_open(
+				writer, process_attr);
 		if (ret) {
-			retval = CMD_ERROR;
+			cmd_ret = CMD_FATAL;
 			goto end;
 		}
 	}
 
-end:
-	if (handle) {
-		lttng_destroy_handle(handle);
+	if (command_args->all) {
+		cmd_ret = run_command_all(cmd_type, session_name, domain_type,
+				process_attr, writer);
+	} else {
+		bool error_occurred = false;
+
+		for (i = 0; i < string_arg_count; i++) {
+			const char *arg = lttng_dynamic_pointer_array_get_pointer(
+					&command_args->string_args, i);
+
+			cmd_ret = run_command_string(cmd_type, session_name,
+					domain_type, process_attr, arg, writer);
+			if (cmd_ret != CMD_SUCCESS) {
+				error_occurred = true;
+				if (cmd_ret == CMD_FATAL) {
+					break;
+				}
+				goto end;
+			}
+		}
+		if (error_occurred) {
+			cmd_ret = CMD_ERROR;
+		}
 	}
-	free(pid_list);
-	return retval;
-}
 
-static
-const char *get_mi_element_command(enum cmd_type cmd_type)
-{
-	switch (cmd_type) {
-	case CMD_TRACK:
-		return mi_lttng_element_command_track;
-	case CMD_UNTRACK:
-		return mi_lttng_element_command_untrack;
-	default:
-		return NULL;
+	if (writer) {
+		/* Close tracker and trackers elements */
+		const int ret = mi_lttng_close_multi_element(
+				writer, 2);
+		if (ret) {
+			cmd_ret = CMD_FATAL;
+			goto end;
+		}
 	}
+end:
+	return cmd_ret;
 }
 
 /*
  * Add/remove tracker to/from session.
  */
-static
-int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
-		int argc, const char **argv)
+static int cmd_track_untrack(enum cmd_type cmd_type,
+		int argc,
+		const char **argv,
+		const char *help_msg)
 {
 	int opt, ret = 0;
+	bool sub_command_failed = false;
+	bool opt_all = false;
+	unsigned int selected_process_attr_tracker_count = 0;
+	const unsigned int command_count =
+			sizeof(process_attr_commands) /
+			sizeof(struct process_attr_command_args);
 	enum cmd_error_code command_ret = CMD_SUCCESS;
-	int success = 1;
 	static poptContext pc;
 	char *session_name = NULL;
+	const char *leftover = NULL;
 	struct mi_writer *writer = NULL;
+	size_t i;
+
+	for (i = 0; i < command_count; i++) {
+		process_attr_command_init(&process_attr_commands[i], i);
+	}
 
 	if (argc < 1) {
 		command_ret = CMD_ERROR;
@@ -346,8 +604,31 @@ int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
 			list_cmd_options(stdout, long_options);
 			goto end;
 		case OPT_SESSION:
+			break;
 		case OPT_PID:
-			opt_pid = 1;
+		case OPT_VPID:
+		case OPT_UID:
+		case OPT_VUID:
+		case OPT_GID:
+		case OPT_VGID:
+			/* See OPT_ enum declaration comment.  */
+			opt--;
+			selected_process_attr_tracker_count++;
+			process_attr_commands[opt].requested = true;
+			if (!opt_str_arg) {
+				continue;
+			}
+			ret = lttng_dynamic_pointer_array_add_pointer(
+					&process_attr_commands[opt].string_args,
+					opt_str_arg);
+			if (ret) {
+				ERR("Allocation failed while parsing command arguments");
+				command_ret = CMD_ERROR;
+				goto end;
+			}
+			break;
+		case OPT_ALL:
+			opt_all = true;
 			break;
 		default:
 			command_ret = CMD_UNDEFINED;
@@ -355,11 +636,53 @@ int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
 		}
 	}
 
-	ret = print_missing_or_multiple_domains(opt_kernel + opt_userspace);
+	ret = print_missing_or_multiple_domains(
+			opt_kernel + opt_userspace, false);
 	if (ret) {
-		ret = CMD_ERROR;
+		command_ret = CMD_ERROR;
+		goto end;
+	}
+
+	if (selected_process_attr_tracker_count == 0) {
+		ERR("At least one process attribute must be specified");
+		command_ret = CMD_ERROR;
 		goto end;
 	}
+	if (opt_all) {
+		/*
+		 * Only one process attribute tracker was specified; find it
+		 * and set it in 'all' mode.
+		 */
+		for (i = 0; i < command_count; i++) {
+			if (!process_attr_commands[i].requested) {
+				continue;
+			}
+			process_attr_commands[i].all = true;
+			if (lttng_dynamic_pointer_array_get_count(
+					    &process_attr_commands[i]
+							     .string_args)) {
+				ERR("The --all option cannot be used with a list of process attribute values");
+				command_ret = CMD_ERROR;
+				goto end;
+			}
+		}
+	} else {
+		for (i = 0; i < command_count; i++) {
+			if (!process_attr_commands[i].requested) {
+				continue;
+			}
+			if (lttng_dynamic_pointer_array_get_count(
+				    &process_attr_commands[i]
+				    .string_args) == 0) {
+				ERR("No process attribute value specified for %s tracker",
+						get_capitalized_process_attr_str(
+								process_attr_commands[i]
+										.process_attr));
+				command_ret = CMD_ERROR;
+				goto end;
+			}
+		}
+	}
 
 	if (!opt_session_name) {
 		session_name = get_session_name();
@@ -371,9 +694,9 @@ int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
 		session_name = opt_session_name;
 	}
 
-	/* Currently only PID tracker is supported */
-	if (!opt_pid) {
-		ERR("Please specify at least one tracker with its expected arguments");
+	leftover = poptGetArg(pc);
+	if (leftover) {
+		ERR("Unknown argument: %s", leftover);
 		command_ret = CMD_ERROR;
 		goto end;
 	}
@@ -403,19 +726,32 @@ int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
 			command_ret = CMD_ERROR;
 			goto end;
 		}
+
+		ret = mi_lttng_trackers_open(writer);
+		if (ret) {
+			goto end;
+		}
 	}
 
-	command_ret = track_untrack_pid(cmd_type,
-			cmd_str, session_name, opt_pid_string,
-			opt_all, writer);
-	if (command_ret != CMD_SUCCESS) {
-		success = 0;
+	/* Execute sub-commands. */
+	for (i = 0; i < command_count; i++) {
+		if (!process_attr_commands[i].requested) {
+			continue;
+		}
+		command_ret = run_command(cmd_type, session_name,
+				&process_attr_commands[i], writer);
+		if (command_ret != CMD_SUCCESS) {
+			sub_command_failed = true;
+			if (command_ret == CMD_FATAL) {
+				break;
+			}
+		}
 	}
 
 	/* Mi closing */
 	if (writer) {
-		/* Close  output element */
-		ret = mi_lttng_writer_close_element(writer);
+		/* Close trackers and output elements */
+		ret = mi_lttng_close_multi_element(writer, 2);
 		if (ret) {
 			command_ret = CMD_ERROR;
 			goto end;
@@ -423,7 +759,8 @@ int cmd_track_untrack(enum cmd_type cmd_type, const char *cmd_str,
 
 		/* Success ? */
 		ret = mi_lttng_writer_write_element_bool(writer,
-				mi_lttng_element_command_success, success);
+				mi_lttng_element_command_success,
+				!sub_command_failed);
 		if (ret) {
 			command_ret = CMD_ERROR;
 			goto end;
@@ -448,16 +785,36 @@ end:
 		command_ret = CMD_ERROR;
 	}
 
+	for (i = 0; i < command_count; i++) {
+		process_attr_command_fini(&process_attr_commands[i]);
+	}
+
 	poptFreeContext(pc);
 	return (int) command_ret;
 }
 
 int cmd_track(int argc, const char **argv)
 {
-	return cmd_track_untrack(CMD_TRACK, "track", argc, argv);
+	static const char *help_msg =
+#ifdef LTTNG_EMBED_HELP
+#include <lttng-track.1.h>
+#else
+	NULL
+#endif
+	;
+
+	return cmd_track_untrack(CMD_TRACK, argc, argv, help_msg);
 }
 
 int cmd_untrack(int argc, const char **argv)
 {
-	return cmd_track_untrack(CMD_UNTRACK, "untrack", argc, argv);
+	static const char *help_msg =
+#ifdef LTTNG_EMBED_HELP
+#include <lttng-untrack.1.h>
+#else
+	NULL
+#endif
+	;
+
+	return cmd_track_untrack(CMD_UNTRACK, argc, argv, help_msg);
 }