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/*
* SPDX-FileCopyrightText: 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
* SPDX-FileCopyrightText: 2020 Francis Deslauriers <francis.deslauriers@efficios.com>
*
* SPDX-License-Identifier: GPL-2.0-only
*
*/
#include <common/compat/getenv.hpp>
#include <common/consumer/consumer.hpp>
#include <common/error.hpp>
#include <common/pipe.hpp>
#include <lttng/constant.h>
#include <lttng/lttng-export.h>
#include <dlfcn.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdio.h>
#include <unistd.h>
static char *pause_pipe_path;
static struct lttng_pipe *pause_pipe;
static int *notifier_notif_consumption_state;
;
int lttng_opt_verbose;
int lttng_opt_mi;
int lttng_opt_quiet;
static void __attribute__((destructor)) pause_pipe_fini()
{
int ret;
if (pause_pipe_path) {
ret = unlink(pause_pipe_path);
if (ret) {
PERROR("Failed to unlink pause pipe: path = %s", pause_pipe_path);
}
}
free(pause_pipe_path);
lttng_pipe_destroy(pause_pipe);
}
extern "C" LTTNG_EXPORT 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("NOTIFIER_PAUSE_PIPE_PATH");
if (!pause_pipe_path_prefix) {
ret = -1;
goto end;
}
notifier_notif_consumption_state = (int *) dlsym(nullptr, "notifier_consumption_paused");
LTTNG_ASSERT(notifier_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;
}
extern "C" LTTNG_EXPORT int __testpoint_sessiond_handle_notifier_event_pipe(void);
int __testpoint_sessiond_handle_notifier_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) {
*notifier_notif_consumption_state = !!value;
DBG("Message received on pause pipe: %s data consumption",
*notifier_notif_consumption_state ? "paused" : "resumed");
}
end:
return ret;
}
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