| 1 | /* |
| 2 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License, version 2 only, as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program 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 General Public License for |
| 11 | * more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along with |
| 14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 16 | */ |
| 17 | |
| 18 | #define _GNU_SOURCE |
| 19 | #include <assert.h> |
| 20 | |
| 21 | #include <common/common.h> |
| 22 | #include <common/sessiond-comm/sessiond-comm.h> |
| 23 | #include <common/uri.h> |
| 24 | #include <common/utils.h> |
| 25 | |
| 26 | #include "fd-limit.h" |
| 27 | #include "jul-thread.h" |
| 28 | #include "lttng-sessiond.h" |
| 29 | |
| 30 | /* |
| 31 | * Note that there is not port here. It's set after this URI is parsed so we |
| 32 | * can let the user define a custom one. However, localhost is ALWAYS the |
| 33 | * default listening address. |
| 34 | */ |
| 35 | static const char *default_reg_uri = "tcp://localhost"; |
| 36 | |
| 37 | /* |
| 38 | * Create and init socket from uri. |
| 39 | */ |
| 40 | static struct lttcomm_sock *init_tcp_socket(void) |
| 41 | { |
| 42 | int ret; |
| 43 | struct lttng_uri *uri = NULL; |
| 44 | struct lttcomm_sock *sock = NULL; |
| 45 | |
| 46 | /* |
| 47 | * This should never fail since the URI is hardcoded and the port is set |
| 48 | * before this thread is launched. |
| 49 | */ |
| 50 | ret = uri_parse(default_reg_uri, &uri); |
| 51 | assert(ret); |
| 52 | assert(jul_tcp_port); |
| 53 | uri->port = jul_tcp_port; |
| 54 | |
| 55 | sock = lttcomm_alloc_sock_from_uri(uri); |
| 56 | uri_free(uri); |
| 57 | if (sock == NULL) { |
| 58 | ERR("[jul-thread] JUL allocating TCP socket"); |
| 59 | goto error; |
| 60 | } |
| 61 | |
| 62 | ret = lttcomm_create_sock(sock); |
| 63 | if (ret < 0) { |
| 64 | goto error; |
| 65 | } |
| 66 | |
| 67 | ret = sock->ops->bind(sock); |
| 68 | if (ret < 0) { |
| 69 | goto error; |
| 70 | } |
| 71 | |
| 72 | ret = sock->ops->listen(sock, -1); |
| 73 | if (ret < 0) { |
| 74 | goto error; |
| 75 | } |
| 76 | |
| 77 | DBG("[jul-thread] Listening on TCP port %u and socket %d", jul_tcp_port, |
| 78 | sock->fd); |
| 79 | |
| 80 | return sock; |
| 81 | |
| 82 | error: |
| 83 | if (sock) { |
| 84 | lttcomm_destroy_sock(sock); |
| 85 | } |
| 86 | return NULL; |
| 87 | } |
| 88 | |
| 89 | /* |
| 90 | * Close and destroy the given TCP socket. |
| 91 | */ |
| 92 | static void destroy_tcp_socket(struct lttcomm_sock *sock) |
| 93 | { |
| 94 | assert(sock); |
| 95 | |
| 96 | DBG3("[jul-thread] Destroy TCP socket on port %u", jul_tcp_port); |
| 97 | |
| 98 | /* This will return gracefully if fd is invalid. */ |
| 99 | sock->ops->close(sock); |
| 100 | lttcomm_destroy_sock(sock); |
| 101 | } |
| 102 | |
| 103 | /* |
| 104 | * This thread manage application notify communication. |
| 105 | */ |
| 106 | void *jul_thread_manage_registration(void *data) |
| 107 | { |
| 108 | int i, ret, pollfd; |
| 109 | uint32_t revents, nb_fd; |
| 110 | struct lttng_poll_event events; |
| 111 | struct lttcomm_sock *reg_sock; |
| 112 | |
| 113 | DBG("[jul-thread] Manage JUL application registration."); |
| 114 | |
| 115 | rcu_register_thread(); |
| 116 | rcu_thread_online(); |
| 117 | |
| 118 | /* Create pollset with size 2, quit pipe and socket. */ |
| 119 | ret = sessiond_set_thread_pollset(&events, 2); |
| 120 | if (ret < 0) { |
| 121 | goto error_poll_create; |
| 122 | } |
| 123 | |
| 124 | reg_sock = init_tcp_socket(); |
| 125 | if (!reg_sock) { |
| 126 | goto error_tcp_socket; |
| 127 | } |
| 128 | |
| 129 | /* Add create valid TCP socket to poll set. */ |
| 130 | ret = lttng_poll_add(&events, reg_sock->fd, |
| 131 | LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP); |
| 132 | if (ret < 0) { |
| 133 | goto error; |
| 134 | } |
| 135 | |
| 136 | while (1) { |
| 137 | DBG3("[jul-thread] Manage JUL polling on %d fds", |
| 138 | LTTNG_POLL_GETNB(&events)); |
| 139 | |
| 140 | /* Inifinite blocking call, waiting for transmission */ |
| 141 | restart: |
| 142 | ret = lttng_poll_wait(&events, -1); |
| 143 | if (ret < 0) { |
| 144 | /* |
| 145 | * Restart interrupted system call. |
| 146 | */ |
| 147 | if (errno == EINTR) { |
| 148 | goto restart; |
| 149 | } |
| 150 | goto error; |
| 151 | } |
| 152 | nb_fd = ret; |
| 153 | |
| 154 | for (i = 0; i < nb_fd; i++) { |
| 155 | /* Fetch once the poll data */ |
| 156 | revents = LTTNG_POLL_GETEV(&events, i); |
| 157 | pollfd = LTTNG_POLL_GETFD(&events, i); |
| 158 | |
| 159 | /* Thread quit pipe has been closed. Killing thread. */ |
| 160 | ret = sessiond_check_thread_quit_pipe(pollfd, revents); |
| 161 | if (ret) { |
| 162 | goto exit; |
| 163 | } |
| 164 | |
| 165 | /* |
| 166 | * Check first if this is a POLLERR since POLLIN is also included |
| 167 | * in an error value thus checking first. |
| 168 | */ |
| 169 | if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) { |
| 170 | /* Removing from the poll set */ |
| 171 | ret = lttng_poll_del(&events, pollfd); |
| 172 | if (ret < 0) { |
| 173 | goto error; |
| 174 | } |
| 175 | |
| 176 | /* FIXME: Nullify the JUL socket for the associated ust app. */ |
| 177 | } else if (revents & (LPOLLIN | LPOLLPRI)) { |
| 178 | /* |
| 179 | * FIXME: Handle JUL registration which must link an UST-app |
| 180 | * and this JUL socket. |
| 181 | */ |
| 182 | } else { |
| 183 | ERR("Unknown poll events %u for sock %d", revents, pollfd); |
| 184 | continue; |
| 185 | } |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | exit: |
| 190 | error: |
| 191 | destroy_tcp_socket(reg_sock); |
| 192 | error_tcp_socket: |
| 193 | lttng_poll_clean(&events); |
| 194 | error_poll_create: |
| 195 | DBG("[jul-thread] is cleaning up and stopping."); |
| 196 | |
| 197 | rcu_thread_offline(); |
| 198 | rcu_unregister_thread(); |
| 199 | return NULL; |
| 200 | } |