projects / lttng-tools.git / blame
| Commit | Line | Data |
|---|---|---|
| 38eb8a68 FD |
1 | /* |
| 2 | * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com> | |
| 3 | * Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com> | |
| 4 | * | |
| 5 | * SPDX-License-Identifier: GPL-2.0-only | |
| 6 | * | |
| 7 | */ | |
| 8 | ||
| 9 | #include <common/compat/getenv.h> | |
| 10 | #include <common/consumer/consumer.h> | |
| 11 | #include <common/pipe.h> | |
| 12 | #include <common/error.h> | |
| 13 | #include <unistd.h> | |
| 14 | #include <stdbool.h> | |
| 15 | #include <lttng/constant.h> | |
| 4bd69c5f | 16 | #include <lttng/lttng-export.h> |
| 38eb8a68 FD |
17 | #include <fcntl.h> |
| 18 | #include <dlfcn.h> | |
| 38eb8a68 FD |
19 | #include <stdio.h> |
| 20 | ||
| 21 | static char *pause_pipe_path; | |
| 22 | static struct lttng_pipe *pause_pipe; | |
| 23 | static int *notifier_notif_consumption_state;; | |
| 24 | ||
| 25 | int lttng_opt_verbose; | |
| 26 | int lttng_opt_mi; | |
| 27 | int lttng_opt_quiet; | |
| 28 | ||
| 29 | static | |
| 30 | void __attribute__((destructor)) pause_pipe_fini(void) | |
| 31 | { | |
| 32 | int ret; | |
| 33 | ||
| 34 | if (pause_pipe_path) { | |
| 35 | ret = unlink(pause_pipe_path); | |
| 36 | if (ret) { | |
| 37 | PERROR("Failed to unlink pause pipe: path = %s", | |
| 38 | pause_pipe_path); | |
| 39 | } | |
| 40 | } | |
| 41 | ||
| 42 | free(pause_pipe_path); | |
| 43 | lttng_pipe_destroy(pause_pipe); | |
| 44 | } | |
| 45 | ||
| 4bd69c5f | 46 | LTTNG_EXPORT int __testpoint_sessiond_thread_notification(void); |
| 38eb8a68 FD |
47 | int __testpoint_sessiond_thread_notification(void) |
| 48 | { | |
| 49 | int ret = 0; | |
| 50 | const char *pause_pipe_path_prefix; | |
| 51 | ||
| 52 | pause_pipe_path_prefix = lttng_secure_getenv( | |
| 53 | "NOTIFIER_PAUSE_PIPE_PATH"); | |
| 54 | if (!pause_pipe_path_prefix) { | |
| 55 | ret = -1; | |
| 56 | goto end; | |
| 57 | } | |
| 58 | ||
| 59 | notifier_notif_consumption_state = dlsym(NULL, "notifier_consumption_paused"); | |
| a0377dfe | 60 | LTTNG_ASSERT(notifier_notif_consumption_state); |
| 38eb8a68 FD |
61 | |
| 62 | ret = asprintf(&pause_pipe_path, "%s", pause_pipe_path_prefix); | |
| 63 | if (ret < 1) { | |
| 64 | ERR("Failed to allocate pause pipe path"); | |
| 65 | goto end; | |
| 66 | } | |
| 67 | ||
| 68 | DBG("Creating pause pipe at %s", pause_pipe_path); | |
| 69 | pause_pipe = lttng_pipe_named_open(pause_pipe_path, | |
| 70 | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP, O_NONBLOCK); | |
| 71 | if (!pause_pipe) { | |
| 72 | ERR("Failed to create pause pipe at %s", pause_pipe_path); | |
| 73 | ret = -1; | |
| 74 | goto end; | |
| 75 | } | |
| 76 | ||
| 77 | /* Only the read end of the pipe is useful to us. */ | |
| 78 | ret = lttng_pipe_write_close(pause_pipe); | |
| 79 | end: | |
| 80 | return ret; | |
| 81 | } | |
| 82 | ||
| 4bd69c5f | 83 | LTTNG_EXPORT int __testpoint_sessiond_handle_notifier_event_pipe(void); |
| 38eb8a68 FD |
84 | int __testpoint_sessiond_handle_notifier_event_pipe(void) |
| 85 | { | |
| 86 | int ret = 0; | |
| 87 | uint8_t value; | |
| 88 | bool value_read = false; | |
| 89 | ||
| 90 | if (!pause_pipe) { | |
| 91 | ret = -1; | |
| 92 | goto end; | |
| 93 | } | |
| 94 | ||
| 95 | /* Purge pipe and only consider the freshest value. */ | |
| 96 | do { | |
| 97 | ret = lttng_pipe_read(pause_pipe, &value, sizeof(value)); | |
| 98 | if (ret == sizeof(value)) { | |
| 99 | value_read = true; | |
| 100 | } | |
| 101 | } while (ret == sizeof(value)); | |
| 102 | ||
| 103 | ret = (errno == EAGAIN) ? 0 : -errno; | |
| 104 | ||
| 105 | if (value_read) { | |
| 106 | *notifier_notif_consumption_state = !!value; | |
| 107 | DBG("Message received on pause pipe: %s data consumption", | |
| 108 | *notifier_notif_consumption_state ? "paused" : "resumed"); | |
| 109 | } | |
| 110 | end: | |
| 111 | return ret; | |
| 112 | } |