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Diffstat (limited to 'src/contrib/conn_pool.h')
| -rw-r--r-- | src/contrib/conn_pool.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/src/contrib/conn_pool.h b/src/contrib/conn_pool.h new file mode 100644 index 0000000..fece34a --- /dev/null +++ b/src/contrib/conn_pool.h @@ -0,0 +1,128 @@ +/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#pragma once + +#include <pthread.h> +#include <stdbool.h> +#include <sys/socket.h> + +#include "contrib/time.h" + +typedef intptr_t conn_pool_fd_t; +extern const conn_pool_fd_t CONN_POOL_FD_INVALID; + +typedef void (*conn_pool_close_cb_t)(conn_pool_fd_t fd); +typedef bool (*conn_pool_invalid_cb_t)(conn_pool_fd_t fd); + +typedef struct { + struct sockaddr_storage src; + struct sockaddr_storage dst; + conn_pool_fd_t fd; + knot_time_t last_active; +} conn_pool_memb_t; + +typedef struct { + size_t capacity; + size_t usage; + knot_timediff_t timeout; + pthread_mutex_t mutex; + pthread_t closing_thread; + conn_pool_close_cb_t close_cb; + conn_pool_invalid_cb_t invalid_cb; + conn_pool_memb_t conns[]; +} conn_pool_t; + +extern conn_pool_t *global_conn_pool; +extern conn_pool_t *global_sessticket_pool; // pool for outgoing QUIC connection session tickets + +/*! + * \brief Allocate connection pool. + * + * \param capacity Connection pool capacity (must be positive number). + * \param timeout Connection timeout (must be positive number). + * \param close_cb Callback for closing fd. + * \param invalid_cb Callback detecting if given fd is already unusable. + * + * \return Connection pool or NULL if error. + */ +conn_pool_t *conn_pool_init(size_t capacity, knot_timediff_t timeout, + conn_pool_close_cb_t close_cb, + conn_pool_invalid_cb_t invalid_cb); + +/*! + * \brief Deallocate the pool, close all connections, terminate closing thread. + * + * \param pool Connection pool. + */ +void conn_pool_deinit(conn_pool_t *pool); + +/*! + * \brief Get and/or set connection timeout. + * + * \param pool Connection pool. + * \param new_timeout Optional: set new timeout (if positive number). + * + * \return Previous value of timeout. + */ +knot_timediff_t conn_pool_timeout(conn_pool_t *pool, + knot_timediff_t new_timeout); + +/*! + * \brief Try to get an open connection if present, check if alive. + * + * \param pool Pool to search in. + * \param src Connection source address. + * \param dst Connection destination address. + * + * \retval -1 If error (no such connection). + * \return >= 0 File descriptor of the connection. + */ +conn_pool_fd_t conn_pool_get(conn_pool_t *pool, + const struct sockaddr_storage *src, + const struct sockaddr_storage *dst); + +/*! + * \brief Put an open connection to the pool, possibly displacing the oldest one there. + * + * \param pool Pool to insert into. + * \param src Connestion source address. + * \param dst Connection destination adress. + * \param fd Connection file descriptor. + * + * \retval -1 If connection stored to free slot. + * \retval fd If not able to store connection. + * \return >= 0 File descriptor of the displaced old connection. + */ +conn_pool_fd_t conn_pool_put(conn_pool_t *pool, + const struct sockaddr_storage *src, + const struct sockaddr_storage *dst, + conn_pool_fd_t fd); + +/*! + * \brief Default close callback calling close() on given fd. + */ +void conn_pool_close_cb_dflt(conn_pool_fd_t fd); + +/*! + * \brief Default invalidness callback detecting socket not ready to write. + */ +bool conn_pool_invalid_cb_dflt(conn_pool_fd_t fd); + +/*! + * \brief Default invalidness callback always reporting valid fd. + */ +bool conn_pool_invalid_cb_allvalid(conn_pool_fd_t fd); |