projects / lttng-tools.git / blame
| Commit | Line | Data |
|---|---|---|
| a58c490f JG |
1 | /* |
| 2 | * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com> | |
| 3 | * | |
| 4 | * This library is free software; you can redistribute it and/or modify it | |
| 5 | * under the terms of the GNU Lesser General Public License, version 2.1 only, | |
| 6 | * as published by the Free Software Foundation. | |
| 7 | * | |
| 8 | * This library is distributed in the hope that it will be useful, but WITHOUT | |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License | |
| 11 | * for more details. | |
| 12 | * | |
| 13 | * You should have received a copy of the GNU Lesser General Public License | |
| 14 | * along with this library; if not, write to the Free Software Foundation, | |
| 15 | * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 16 | */ | |
| 17 | ||
| 18 | #ifndef LTTNG_NOTIFICATION_CHANNEL_INTERNAL_H | |
| 19 | #define LTTNG_NOTIFICATION_CHANNEL_INTERNAL_H | |
| 20 | ||
| 21 | #include <lttng/notification/channel.h> | |
| 22 | #include <common/macros.h> | |
| 23 | #include <common/dynamic-buffer.h> | |
| 24 | #include <stdint.h> | |
| 25 | #include <stdbool.h> | |
| 26 | #include <pthread.h> | |
| 27 | #include <urcu/list.h> | |
| 28 | ||
| 29 | #define LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR 1 | |
| 30 | #define LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR 0 | |
| 31 | ||
| 32 | enum lttng_notification_channel_message_type { | |
| 33 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN = -1, | |
| 34 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE = 0, | |
| 35 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE = 1, | |
| 36 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE = 2, | |
| 37 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY = 3, | |
| 38 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION = 4, | |
| 39 | LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED = 5, | |
| 40 | }; | |
| 41 | ||
| 42 | struct lttng_notification_channel_message { | |
| 43 | /* enum lttng_notification_channel_message_type */ | |
| 44 | int8_t type; | |
| 45 | /* Size of the payload following this field. */ | |
| 46 | uint32_t size; | |
| 47 | char payload[]; | |
| 48 | } LTTNG_PACKED; | |
| 49 | ||
| 50 | struct lttng_notification_channel_command_handshake { | |
| 51 | uint8_t major; | |
| 52 | uint8_t minor; | |
| 53 | } LTTNG_PACKED; | |
| 54 | ||
| 55 | struct lttng_notification_channel_command_reply { | |
| 56 | /* enum lttng_notification_channel_status */ | |
| 57 | int8_t status; | |
| 58 | } LTTNG_PACKED; | |
| 59 | ||
| 60 | struct pending_notification { | |
| 61 | /* NULL means "notification dropped". */ | |
| 62 | struct lttng_notification *notification; | |
| 63 | struct cds_list_head node; | |
| 64 | }; | |
| 65 | ||
| 66 | /* | |
| 67 | * The notification channel protocol is bidirectional and accomodates | |
| 68 | * synchronous and asynchronous communication modes: | |
| 69 | * | |
| 70 | * - Synchronous: commands emitted by the client to which a reply is expected | |
| 71 | * (e.g. subscribing/unsubscribing to conditions), | |
| 72 | * - Asynchronous: notifications which are sent by the lttng_endpoint to the | |
| 4149ace8 | 73 | * client as one of the subscribed condition has occurred. |
| a58c490f JG |
74 | * |
| 75 | * The nature of this hybrid communication mode means that asynchronous messages | |
| 76 | * (e.g. notifications) may be interleaved between synchronous messages (e.g. a | |
| 77 | * command and its reply). | |
| 78 | * | |
| 79 | * Notifications that are received between a command and its reply and enqueued | |
| 80 | * in the pending_notifications list. | |
| 81 | */ | |
| 82 | struct lttng_notification_channel { | |
| 83 | pthread_mutex_t lock; | |
| 84 | int socket; | |
| 85 | struct { | |
| 86 | /* Count of pending notifications. */ | |
| 87 | unsigned int count; | |
| 88 | /* List of struct pending_notification. */ | |
| 89 | struct cds_list_head list; | |
| 90 | } pending_notifications; | |
| 91 | struct lttng_dynamic_buffer reception_buffer; | |
| 92 | /* Sessiond notification protocol version. */ | |
| 93 | struct { | |
| 94 | bool set; | |
| 95 | int8_t major, minor; | |
| 96 | } version; | |
| 97 | }; | |
| 98 | ||
| 99 | #endif /* LTTNG_NOTIFICATION_CHANNEL_INTERNAL_H */ |