--- /dev/null
+/*
+ * Copyright (C) 2019 - Jonathan Rajotte <jonathan.rajotte-julien@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.
+ *
+ * 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 <assert.h>
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <common/defaults.h>
+#include <common/error.h>
+#include <common/utils.h>
+
+#include "clear.h"
+#include "session.h"
+#include "ust-app.h"
+#include "kernel.h"
+#include "cmd.h"
+
+struct cmd_clear_session_reply_context {
+ int reply_sock_fd;
+};
+
+static
+void cmd_clear_session_reply(const struct ltt_session *session,
+ void *_reply_context)
+{
+ int ret;
+ ssize_t comm_ret;
+ const struct cmd_clear_session_reply_context *reply_context =
+ _reply_context;
+ struct lttcomm_lttng_msg llm = {
+ .cmd_type = LTTNG_CLEAR_SESSION,
+ .ret_code = LTTNG_OK,
+ .pid = UINT32_MAX,
+ .cmd_header_size = 0,
+ .data_size = 0,
+ };
+
+ DBG("End of clear command: replying to client");
+ comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
+ &llm, sizeof(llm));
+ if (comm_ret != (ssize_t) sizeof(llm)) {
+ ERR("Failed to send result of session \"%s\" clear to client",
+ session->name);
+ }
+ ret = close(reply_context->reply_sock_fd);
+ if (ret) {
+ PERROR("Failed to close client socket in deferred session clear reply");
+ }
+ free(_reply_context);
+}
+
+int cmd_clear_session(struct ltt_session *session, int *sock_fd)
+{
+ int ret = LTTNG_OK;
+ struct cmd_clear_session_reply_context *reply_context = NULL;
+ bool session_was_active = false;
+ struct ltt_kernel_session *ksession;
+ struct ltt_ust_session *usess;
+
+ ksession = session->kernel_session;
+ usess = session->ust_session;
+
+ if (sock_fd) {
+ reply_context = zmalloc(sizeof(*reply_context));
+ if (!reply_context) {
+ ret = LTTNG_ERR_NOMEM;
+ goto end;
+ }
+ reply_context->reply_sock_fd = *sock_fd;
+ }
+
+ if (!session->has_been_started) {
+ /*
+ * Nothing to be cleared, this is not an error: there is
+ * indeed nothing to do, and there is no reason why we
+ * should return an error to the user.
+ */
+ goto end;
+ }
+
+ /* Unsupported feature in lttng-relayd before 2.11. */
+ if (session->consumer->type == CONSUMER_DST_NET &&
+ (session->consumer->relay_major_version == 2 &&
+ session->consumer->relay_minor_version < 12)) {
+ ret = LTTNG_ERR_CLEAR_NOT_AVAILABLE_RELAY;
+ goto end;
+ }
+ if (session->consumer->type == CONSUMER_DST_NET &&
+ !session->consumer->relay_allows_clear) {
+ ret = LTTNG_ERR_CLEAR_NOT_AVAILABLE_RELAY;
+ goto end;
+ }
+
+ /*
+ * After a stop followed by a clear, all subsequent clear are
+ * effect-less until start is performed.
+ */
+ if (session->cleared_after_last_stop) {
+ ret = LTTNG_OK;
+ goto end;
+ }
+
+ /*
+ * After a stop followed by a rotation, all subsequent clear are effect-less
+ * until start is performed.
+ */
+ if (session->rotated_after_last_stop) {
+ ret = LTTNG_OK;
+ goto end;
+ }
+
+ session_was_active = session->active;
+ if (session_was_active) {
+ ret = stop_kernel_session(ksession);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ if (usess && usess->active) {
+ ret = ust_app_stop_trace_all(usess);
+ if (ret < 0) {
+ ret = LTTNG_ERR_UST_STOP_FAIL;
+ goto end;
+ }
+ }
+ }
+
+ /*
+ * Clear active kernel and UST session buffers.
+ */
+ if (session->kernel_session) {
+ ret = kernel_clear_session(session);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+ if (session->ust_session) {
+ ret = ust_app_clear_session(session);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+
+ if (session->output_traces) {
+ /*
+ * Use rotation to delete local and remote stream files.
+ */
+ if (reply_context) {
+ ret = session_add_clear_notifier(session,
+ cmd_clear_session_reply,
+ (void *) reply_context);
+ if (ret) {
+ ret = LTTNG_ERR_FATAL;
+ goto end;
+ }
+ /*
+ * On success, ownership of reply_context has been
+ * passed to session_add_clear_notifier().
+ */
+ reply_context = NULL;
+ *sock_fd = -1;
+ }
+ ret = cmd_rotate_session(session, NULL, true,
+ LTTNG_TRACE_CHUNK_COMMAND_TYPE_DELETE);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+ if (!session->active) {
+ session->cleared_after_last_stop = true;
+ }
+ if (session_was_active) {
+ /* Kernel tracing */
+ if (ksession != NULL) {
+ DBG("Start kernel tracing session \"%s\"",
+ session->name);
+ ret = start_kernel_session(ksession);
+ if (ret != LTTNG_OK) {
+ goto end;
+ }
+ }
+
+ /* Flag session that trace should start automatically */
+ if (usess) {
+ int int_ret = ust_app_start_trace_all(usess);
+
+ if (int_ret < 0) {
+ ret = LTTNG_ERR_UST_START_FAIL;
+ goto end;
+ }
+ }
+ }
+ ret = LTTNG_OK;
+end:
+ free(reply_context);
+ return ret;
+}
projects / lttng-tools.git / commitdiff
