--- /dev/null
+/*
+ * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#include <common/compat/getenv.h>
+#include <common/consumer/consumer.h>
+#include <common/pipe.h>
+#include <common/error.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <lttng/constant.h>
+#include <fcntl.h>
+#include <dlfcn.h>
+#include <assert.h>
+#include <stdio.h>
+
+static char *pause_pipe_path;
+static struct lttng_pipe *pause_pipe;
+static int *trigger_notif_consumption_state;;
+
+int lttng_opt_verbose;
+int lttng_opt_mi;
+int lttng_opt_quiet;
+
+static
+void __attribute__((destructor)) pause_pipe_fini(void)
+{
+ int ret;
+
+ if (pause_pipe_path) {
+ ret = unlink(pause_pipe_path);
+ if (ret) {
+ PERROR("unlink pause pipe");
+ }
+ }
+
+ free(pause_pipe_path);
+ lttng_pipe_destroy(pause_pipe);
+}
+
+/*
+ */
+int __testpoint_sessiond_thread_notification(void);
+int __testpoint_sessiond_thread_notification(void)
+{
+ int ret = 0;
+ const char *pause_pipe_path_prefix;
+
+ pause_pipe_path_prefix = lttng_secure_getenv(
+ "TRIGGER_PAUSE_PIPE_PATH");
+ if (!pause_pipe_path_prefix) {
+ ret = -1;
+ goto end;
+ }
+
+ trigger_notif_consumption_state = dlsym(NULL, "trigger_consumption_paused");
+ assert(trigger_notif_consumption_state);
+
+ ret = asprintf(&pause_pipe_path, "%s", pause_pipe_path_prefix);
+ if (ret < 1) {
+ ERR("Failed to allocate pause pipe path");
+ goto end;
+ }
+
+ DBG("Creating pause pipe at %s", pause_pipe_path);
+ pause_pipe = lttng_pipe_named_open(pause_pipe_path,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP, O_NONBLOCK);
+ if (!pause_pipe) {
+ ERR("Failed to create pause pipe at %s", pause_pipe_path);
+ ret = -1;
+ goto end;
+ }
+
+ /* Only the read end of the pipe is useful to us. */
+ ret = lttng_pipe_write_close(pause_pipe);
+end:
+ return ret;
+}
+
+int __testpoint_sessiond_handle_trigger_event_pipe(void);
+int __testpoint_sessiond_handle_trigger_event_pipe(void)
+{
+ int ret = 0;
+ uint8_t value;
+ bool value_read = false;
+
+ if (!pause_pipe) {
+ ret = -1;
+ goto end;
+ }
+
+ /* Purge pipe and only consider the freshest value. */
+ do {
+ ret = lttng_pipe_read(pause_pipe, &value, sizeof(value));
+ if (ret == sizeof(value)) {
+ value_read = true;
+ }
+ } while (ret == sizeof(value));
+
+ ret = (errno == EAGAIN) ? 0 : -errno;
+
+ if (value_read) {
+ *trigger_notif_consumption_state = !!value;
+ DBG("Message received on pause pipe: %s data consumption",
+ *trigger_notif_consumption_state ? "paused" : "resumed");
+ }
+end:
+ return ret;
+}