Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 1 | /*! \file osmo_io.c |
| 2 | * New osmocom async I/O API. |
| 3 | * |
| 4 | * (C) 2022 by Harald Welte <laforge@osmocom.org> |
| 5 | * (C) 2022-2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| 6 | * Author: Daniel Willmann <dwillmann@sysmocom.de> |
| 7 | * |
| 8 | * All Rights Reserved. |
| 9 | * |
| 10 | * SPDX-License-Identifier: GPL-2.0+ |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later version. |
| 16 | * |
| 17 | * This program is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU General Public License for more details. |
| 21 | */ |
| 22 | |
| 23 | #include "../config.h" |
| 24 | #if defined(__linux__) |
| 25 | |
| 26 | #include <fcntl.h> |
| 27 | #include <stdio.h> |
| 28 | #include <stdlib.h> |
| 29 | #include <talloc.h> |
| 30 | #include <unistd.h> |
| 31 | #include <string.h> |
| 32 | #include <stdbool.h> |
| 33 | #include <errno.h> |
| 34 | |
| 35 | #include <osmocom/core/osmo_io.h> |
| 36 | #include <osmocom/core/linuxlist.h> |
| 37 | #include <osmocom/core/logging.h> |
| 38 | #include <osmocom/core/msgb.h> |
| 39 | #include <osmocom/core/socket.h> |
| 40 | #include <osmocom/core/talloc.h> |
| 41 | #include <osmocom/core/utils.h> |
| 42 | |
| 43 | #include "osmo_io_internal.h" |
| 44 | |
| 45 | /*! This environment variable can be set to manually set the backend used in osmo_io */ |
| 46 | #define OSMO_IO_BACKEND_ENV "LIBOSMO_IO_BACKEND" |
| 47 | |
| 48 | const struct value_string osmo_io_backend_names[] = { |
| 49 | { OSMO_IO_BACKEND_POLL, "poll" }, |
| 50 | { 0, NULL } |
| 51 | }; |
| 52 | |
| 53 | static enum osmo_io_backend g_io_backend; |
| 54 | |
| 55 | /* Used by some tests, can't be static */ |
| 56 | struct iofd_backend_ops osmo_iofd_ops; |
| 57 | |
| 58 | /*! initialize osmo_io for the current thread */ |
| 59 | void osmo_iofd_init(void) |
| 60 | { |
| 61 | switch (g_io_backend) { |
| 62 | case OSMO_IO_BACKEND_POLL: |
| 63 | break; |
| 64 | default: |
| 65 | OSMO_ASSERT(0); |
| 66 | break; |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | /* ensure main thread always has pre-initialized osmo_io |
| 71 | * priority 103: run after on_dso_load_select */ |
| 72 | static __attribute__((constructor(103))) void on_dso_load_osmo_io(void) |
| 73 | { |
| 74 | char *backend = getenv(OSMO_IO_BACKEND_ENV); |
| 75 | if (backend == NULL) |
| 76 | backend = OSMO_IO_BACKEND_DEFAULT; |
| 77 | |
| 78 | if (!strcmp("POLL", backend)) { |
| 79 | g_io_backend = OSMO_IO_BACKEND_POLL; |
| 80 | osmo_iofd_ops = iofd_poll_ops; |
| 81 | } else { |
| 82 | fprintf(stderr, "Invalid osmo_io backend requested: \"%s\"\nCheck the environment variable %s\n", backend, OSMO_IO_BACKEND_ENV); |
| 83 | exit(1); |
| 84 | } |
| 85 | |
| 86 | osmo_iofd_init(); |
| 87 | } |
| 88 | |
| 89 | /*! Allocate the msghdr |
| 90 | * \param[in] iofd the osmo_io file structure |
| 91 | * \param[in] action the action this msg(hdr) is for (read, write, ..) |
| 92 | * \param[in] msg the msg buffer to use. Will allocate a new one if NULL |
| 93 | * \returns the newly allocated msghdr or NULL in case of error */ |
| 94 | struct iofd_msghdr *iofd_msghdr_alloc(struct osmo_io_fd *iofd, enum iofd_msg_action action, struct msgb *msg) |
| 95 | { |
| 96 | struct iofd_msghdr *hdr = talloc_zero(iofd, struct iofd_msghdr); |
| 97 | if (!hdr) |
| 98 | return NULL; |
| 99 | if (!msg) { |
| 100 | msg = iofd_msgb_alloc(iofd); |
| 101 | if (!msg) { |
| 102 | talloc_free(hdr); |
| 103 | return NULL; |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | hdr->action = action; |
| 108 | hdr->iofd = iofd; |
| 109 | hdr->msg = msg; |
| 110 | |
| 111 | return hdr; |
| 112 | } |
| 113 | |
| 114 | /*! Free the msghdr |
| 115 | * \param[in] msghdr the msghdr to free |
| 116 | */ |
| 117 | void iofd_msghdr_free(struct iofd_msghdr *msghdr) |
| 118 | { |
| 119 | /* msghdr->msg is never owned by msghdr, it will either be freed in the send path or |
| 120 | * or passed on to the read callback which takes ownership. */ |
| 121 | talloc_free(msghdr); |
| 122 | } |
| 123 | |
| 124 | /*! convenience wrapper to call msgb_alloc with parameters from osmo_io_fd */ |
| 125 | struct msgb *iofd_msgb_alloc(struct osmo_io_fd *iofd) |
| 126 | { |
| 127 | uint16_t headroom = iofd->msgb_alloc.headroom; |
| 128 | |
| 129 | OSMO_ASSERT(iofd->msgb_alloc.size < 0xffff - headroom); |
| 130 | return msgb_alloc_headroom_c(iofd->msgb_alloc.ctx, |
Pau Espin Pedrol | 63e45e6 | 2023-06-16 16:19:45 +0200 | [diff] [blame] | 131 | iofd->msgb_alloc.size + headroom, headroom, |
| 132 | iofd->name ? : "iofd_msgb"); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 133 | } |
| 134 | |
| 135 | /*! return the pending msgb in iofd or NULL if there is none*/ |
| 136 | struct msgb *iofd_msgb_pending(struct osmo_io_fd *iofd) |
| 137 | { |
| 138 | struct msgb *msg = NULL; |
| 139 | |
| 140 | msg = iofd->pending; |
| 141 | iofd->pending = NULL; |
| 142 | |
| 143 | return msg; |
| 144 | } |
| 145 | |
| 146 | /*! Return the pending msgb or allocate and return a new one */ |
| 147 | struct msgb *iofd_msgb_pending_or_alloc(struct osmo_io_fd *iofd) |
| 148 | { |
| 149 | struct msgb *msg = NULL; |
| 150 | |
| 151 | msg = iofd_msgb_pending(iofd); |
| 152 | if (!msg) |
| 153 | msg = iofd_msgb_alloc(iofd); |
| 154 | |
| 155 | return msg; |
| 156 | } |
| 157 | |
| 158 | /*! Enqueue a message to be sent |
| 159 | * |
| 160 | * Enqueues the message at the back of the queue provided there is enough space. |
| 161 | * \param[in] iofd the file descriptor |
| 162 | * \param[in] msghdr the message to enqueue |
| 163 | * \returns 0 if the message was enqueued succcessfully, |
| 164 | * -ENOSPC if the queue already contains the maximum number of messages |
| 165 | */ |
| 166 | int iofd_txqueue_enqueue(struct osmo_io_fd *iofd, struct iofd_msghdr *msghdr) |
| 167 | { |
| 168 | if (iofd->tx_queue.current_length >= iofd->tx_queue.max_length) |
| 169 | return -ENOSPC; |
| 170 | |
| 171 | llist_add_tail(&msghdr->list, &iofd->tx_queue.msg_queue); |
| 172 | iofd->tx_queue.current_length++; |
| 173 | |
Daniel Willmann | e4ecd99 | 2023-06-30 10:52:11 +0200 | [diff] [blame] | 174 | if (iofd->tx_queue.current_length == 1 && !IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 175 | osmo_iofd_ops.write_enable(iofd); |
| 176 | |
| 177 | return 0; |
| 178 | } |
| 179 | |
| 180 | /*! Enqueue a message at the front |
| 181 | * |
| 182 | * Used to enqueue a msgb from a partial send again. This function will always |
| 183 | * enqueue the message, even if the maximum number of messages is reached. |
| 184 | * \param[in] iofd the file descriptor |
| 185 | * \param[in] msghdr the message to enqueue |
| 186 | */ |
| 187 | void iofd_txqueue_enqueue_front(struct osmo_io_fd *iofd, struct iofd_msghdr *msghdr) |
| 188 | { |
| 189 | llist_add(&msghdr->list, &iofd->tx_queue.msg_queue); |
| 190 | iofd->tx_queue.current_length++; |
Daniel Willmann | e4ecd99 | 2023-06-30 10:52:11 +0200 | [diff] [blame] | 191 | |
| 192 | if (iofd->tx_queue.current_length == 1 && !IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
| 193 | osmo_iofd_ops.write_enable(iofd); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 194 | } |
| 195 | |
| 196 | /*! Dequeue a message from the front |
| 197 | * |
| 198 | * \param[in] iofd the file descriptor |
| 199 | * \returns the msghdr from the front of the queue or NULL if the queue is empty |
| 200 | */ |
| 201 | struct iofd_msghdr *iofd_txqueue_dequeue(struct osmo_io_fd *iofd) |
| 202 | { |
| 203 | struct llist_head *lh; |
| 204 | |
| 205 | if (iofd->tx_queue.current_length == 0) |
| 206 | return NULL; |
| 207 | |
| 208 | lh = iofd->tx_queue.msg_queue.next; |
| 209 | |
| 210 | OSMO_ASSERT(lh); |
| 211 | iofd->tx_queue.current_length--; |
| 212 | llist_del(lh); |
| 213 | |
| 214 | if (iofd->tx_queue.current_length == 0) |
| 215 | osmo_iofd_ops.write_disable(iofd); |
| 216 | |
| 217 | return llist_entry(lh, struct iofd_msghdr, list); |
| 218 | } |
| 219 | |
| 220 | /*! Handle segmentation of the msg. If this function returns *_HANDLE_ONE or MORE then the data in msg will contain |
| 221 | * one complete message. |
| 222 | * If there are bytes left over, *pending_out will point to a msgb with the remaining data. |
| 223 | */ |
| 224 | static enum iofd_seg_act iofd_handle_segmentation(struct osmo_io_fd *iofd, struct msgb *msg, struct msgb **pending_out) |
| 225 | { |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 226 | int extra_len, received_len; |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 227 | struct msgb *msg_pending; |
| 228 | |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 229 | received_len = msgb_length(msg); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 230 | |
| 231 | if (!iofd->io_ops.segmentation_cb) { |
| 232 | *pending_out = NULL; |
| 233 | return IOFD_SEG_ACT_HANDLE_ONE; |
| 234 | } |
| 235 | |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 236 | int expected_len = iofd->io_ops.segmentation_cb(msg); |
| 237 | if (expected_len == -EAGAIN) { |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 238 | goto defer; |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 239 | } else if (expected_len < 0) { |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 240 | /* Something is wrong, skip this msgb */ |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 241 | LOGPIO(iofd, LOGL_ERROR, "segmentation_cb returned error (%d), skipping msg of size %d\n", |
| 242 | expected_len, received_len); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 243 | *pending_out = NULL; |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 244 | msgb_free(msg); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 245 | return IOFD_SEG_ACT_DEFER; |
| 246 | } |
| 247 | |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 248 | extra_len = received_len - expected_len; |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 249 | /* No segmentation needed, return the whole msgb */ |
| 250 | if (extra_len == 0) { |
| 251 | *pending_out = NULL; |
| 252 | return IOFD_SEG_ACT_HANDLE_ONE; |
| 253 | /* segment is incomplete */ |
| 254 | } else if (extra_len < 0) { |
| 255 | goto defer; |
| 256 | } |
| 257 | |
| 258 | /* msgb contains more than one segment */ |
| 259 | /* Copy the trailing data over */ |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 260 | msg_pending = iofd_msgb_alloc(iofd); |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 261 | memcpy(msgb_data(msg_pending), msgb_data(msg) + expected_len, extra_len); |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 262 | msgb_put(msg_pending, extra_len); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 263 | *pending_out = msg_pending; |
| 264 | |
| 265 | /* Trim the original msgb to size */ |
arehbein | c0aa4bd | 2023-06-16 22:31:32 +0200 | [diff] [blame] | 266 | msgb_trim(msg, expected_len); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 267 | return IOFD_SEG_ACT_HANDLE_MORE; |
Daniel Willmann | d4d0370 | 2023-05-17 12:38:14 +0200 | [diff] [blame] | 268 | |
| 269 | defer: |
| 270 | *pending_out = msg; |
| 271 | return IOFD_SEG_ACT_DEFER; |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 272 | } |
| 273 | |
| 274 | /*! Restore message boundaries on read() and pass individual messages to the read callback |
| 275 | */ |
| 276 | void iofd_handle_segmented_read(struct osmo_io_fd *iofd, struct msgb *msg, int rc) |
| 277 | { |
| 278 | int res; |
| 279 | struct msgb *pending = NULL; |
| 280 | |
| 281 | if (rc <= 0) { |
| 282 | iofd->io_ops.read_cb(iofd, rc, msg); |
| 283 | return; |
| 284 | } |
| 285 | |
| 286 | do { |
| 287 | res = iofd_handle_segmentation(iofd, msg, &pending); |
| 288 | if (res != IOFD_SEG_ACT_DEFER || rc < 0) |
| 289 | iofd->io_ops.read_cb(iofd, rc, msg); |
| 290 | if (res == IOFD_SEG_ACT_HANDLE_MORE) |
| 291 | msg = pending; |
| 292 | } while (res == IOFD_SEG_ACT_HANDLE_MORE); |
| 293 | |
| 294 | OSMO_ASSERT(iofd->pending == NULL); |
| 295 | iofd->pending = pending; |
| 296 | } |
| 297 | |
| 298 | /* Public functions */ |
| 299 | |
| 300 | /*! Send a message through a connected socket |
| 301 | * |
| 302 | * Appends the message to the internal transmit queue. |
| 303 | * If the function returns success (0) it will take ownership of the msgb and |
| 304 | * internally call msgb_free() after the write request completes. |
| 305 | * In case of an error the msgb needs to be freed by the caller. |
| 306 | * \param[in] iofd file descriptor to write to |
| 307 | * \param[in] msg message buffer to write |
| 308 | * \returns 0 in case of success; a negative value in case of error |
| 309 | */ |
| 310 | int osmo_iofd_write_msgb(struct osmo_io_fd *iofd, struct msgb *msg) |
| 311 | { |
| 312 | int rc; |
| 313 | struct iofd_msghdr *msghdr = iofd_msghdr_alloc(iofd, IOFD_ACT_WRITE, msg); |
| 314 | if (!msghdr) |
| 315 | return -ENOMEM; |
| 316 | |
| 317 | msghdr->flags = 0; |
| 318 | msghdr->iov[0].iov_base = msgb_data(msghdr->msg); |
| 319 | msghdr->iov[0].iov_len = msgb_length(msghdr->msg); |
| 320 | msghdr->hdr.msg_iov = &msghdr->iov[0]; |
| 321 | msghdr->hdr.msg_iovlen = 1; |
| 322 | |
| 323 | rc = iofd_txqueue_enqueue(iofd, msghdr); |
| 324 | if (rc < 0) { |
| 325 | iofd_msghdr_free(msghdr); |
| 326 | LOGPIO(iofd, LOGL_ERROR, "enqueueing message failed (%d). Rejecting msgb\n", rc); |
| 327 | return rc; |
| 328 | } |
| 329 | |
| 330 | return 0; |
| 331 | } |
| 332 | |
| 333 | /*! Send a message through an unconnected socket |
| 334 | * |
| 335 | * Appends the message to the internal transmit queue. |
| 336 | * If the function returns success (0), it will take ownership of the msgb and |
| 337 | * internally call msgb_free() after the write request completes. |
| 338 | * In case of an error the msgb needs to be freed by the caller. |
| 339 | * \param[in] iofd file descriptor to write to |
| 340 | * \param[in] msg message buffer to send |
| 341 | * \param[in] sendto_flags Flags to pass to the send call |
| 342 | * \param[in] dest destination address to send the message to |
| 343 | * \returns 0 in case of success; a negative value in case of error |
| 344 | */ |
| 345 | int osmo_iofd_sendto_msgb(struct osmo_io_fd *iofd, struct msgb *msg, int sendto_flags, const struct osmo_sockaddr *dest) |
| 346 | { |
| 347 | int rc; |
| 348 | |
| 349 | OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_RECVFROM_SENDTO); |
| 350 | |
| 351 | struct iofd_msghdr *msghdr = iofd_msghdr_alloc(iofd, IOFD_ACT_SENDTO, msg); |
| 352 | if (!msghdr) |
| 353 | return -ENOMEM; |
| 354 | |
| 355 | if (dest) { |
| 356 | msghdr->osa = *dest; |
| 357 | msghdr->hdr.msg_name = &msghdr->osa.u.sa; |
| 358 | msghdr->hdr.msg_namelen = osmo_sockaddr_size(&msghdr->osa); |
| 359 | } |
| 360 | msghdr->flags = sendto_flags; |
| 361 | msghdr->iov[0].iov_base = msgb_data(msghdr->msg); |
| 362 | msghdr->iov[0].iov_len = msgb_length(msghdr->msg); |
| 363 | msghdr->hdr.msg_iov = &msghdr->iov[0]; |
| 364 | msghdr->hdr.msg_iovlen = 1; |
| 365 | |
| 366 | rc = iofd_txqueue_enqueue(iofd, msghdr); |
| 367 | if (rc < 0) { |
| 368 | iofd_msghdr_free(msghdr); |
| 369 | LOGPIO(iofd, LOGL_ERROR, "enqueueing message failed (%d). Rejecting msgb\n", rc); |
| 370 | return rc; |
| 371 | } |
| 372 | |
| 373 | return 0; |
| 374 | } |
| 375 | |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 376 | /*! Allocate and setup a new iofd |
| 377 | * \param[in] ctx the parent context from which to allocate |
| 378 | * \param[in] fd the underlying system file descriptor |
| 379 | * \param[in] name the name of the iofd |
| 380 | * \param[in] mode the mode of the iofd, whether it should use read()/write(), sendto()/recvfrom() |
| 381 | * \param[in] ioops structure with read/write/send/recv callbacks |
| 382 | * \param[in] data user data pointer accessible by the ioops callbacks |
| 383 | * \returns The newly allocated osmo_io_fd struct or NULL on failure |
| 384 | */ |
| 385 | struct osmo_io_fd *osmo_iofd_setup(const void *ctx, int fd, const char *name, enum osmo_io_fd_mode mode, |
| 386 | const struct osmo_io_ops *ioops, void *data) |
| 387 | { |
| 388 | struct osmo_io_fd *iofd = talloc_zero(ctx, struct osmo_io_fd); |
| 389 | if (!iofd) |
| 390 | return NULL; |
| 391 | |
| 392 | iofd->fd = fd; |
| 393 | iofd->mode = mode; |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 394 | IOFD_FLAG_SET(iofd, IOFD_FLAG_CLOSED); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 395 | |
Pau Espin Pedrol | 63e45e6 | 2023-06-16 16:19:45 +0200 | [diff] [blame] | 396 | if (name) |
| 397 | iofd->name = talloc_strdup(iofd, name); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 398 | |
| 399 | if (ioops) |
| 400 | iofd->io_ops = *ioops; |
| 401 | |
| 402 | iofd->pending = NULL; |
| 403 | |
| 404 | iofd->data = data; |
| 405 | |
| 406 | iofd->msgb_alloc.ctx = ctx; |
| 407 | iofd->msgb_alloc.size = OSMO_IO_DEFAULT_MSGB_SIZE; |
| 408 | iofd->msgb_alloc.headroom = OSMO_IO_DEFAULT_MSGB_HEADROOM; |
| 409 | |
| 410 | iofd->tx_queue.max_length = 32; |
| 411 | INIT_LLIST_HEAD(&iofd->tx_queue.msg_queue); |
| 412 | |
| 413 | return iofd; |
| 414 | } |
| 415 | |
| 416 | /*! Register the fd with the underlying backend |
| 417 | * |
| 418 | * \param[in] iofd the iofd file descriptor |
| 419 | * \param[in] fd the system fd number that will be registeres. If negative will use the one already set. |
| 420 | * \returns zero on success, a negative value on error |
| 421 | */ |
| 422 | int osmo_iofd_register(struct osmo_io_fd *iofd, int fd) |
| 423 | { |
Daniel Willmann | eb9edba | 2023-06-06 16:53:38 +0200 | [diff] [blame] | 424 | int rc = 0; |
| 425 | |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 426 | if (fd >= 0) |
| 427 | iofd->fd = fd; |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 428 | |
| 429 | if (osmo_iofd_ops.register_fd) |
Daniel Willmann | eb9edba | 2023-06-06 16:53:38 +0200 | [diff] [blame] | 430 | rc = osmo_iofd_ops.register_fd(iofd); |
Daniel Willmann | acb9776 | 2023-06-07 17:02:31 +0200 | [diff] [blame] | 431 | if (rc) |
| 432 | return rc; |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 433 | |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 434 | IOFD_FLAG_UNSET(iofd, IOFD_FLAG_CLOSED); |
Daniel Willmann | eb9edba | 2023-06-06 16:53:38 +0200 | [diff] [blame] | 435 | osmo_iofd_ops.read_enable(iofd); |
| 436 | osmo_iofd_ops.write_enable(iofd); |
| 437 | |
| 438 | return rc; |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 439 | } |
| 440 | |
| 441 | /*! Unregister the fd from the underlying backend |
| 442 | * |
| 443 | * \param[in] iofd the file descriptor |
| 444 | * \returns zero on success, a negative value on error |
| 445 | */ |
| 446 | int osmo_iofd_unregister(struct osmo_io_fd *iofd) |
| 447 | { |
| 448 | if (osmo_iofd_ops.unregister_fd) |
| 449 | return osmo_iofd_ops.unregister_fd(iofd); |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 450 | IOFD_FLAG_SET(iofd, IOFD_FLAG_CLOSED); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 451 | |
| 452 | return 0; |
| 453 | } |
| 454 | |
| 455 | /*! Get the number of messages in the tx queue |
| 456 | * |
| 457 | * \param[in] iofd the file descriptor |
| 458 | */ |
| 459 | unsigned int osmo_iofd_txqueue_len(struct osmo_io_fd *iofd) |
| 460 | { |
| 461 | return iofd->tx_queue.current_length; |
| 462 | } |
| 463 | |
| 464 | /*! Clear the transmit queue of the the iofd |
| 465 | * |
| 466 | * This function frees all messages currently pending in the transmit queue |
| 467 | * \param[in] iofd the file descriptor |
| 468 | */ |
| 469 | void osmo_iofd_txqueue_clear(struct osmo_io_fd *iofd) |
| 470 | { |
| 471 | struct iofd_msghdr *hdr; |
| 472 | while ((hdr = iofd_txqueue_dequeue(iofd))) { |
| 473 | msgb_free(hdr->msg); |
| 474 | iofd_msghdr_free(hdr); |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | /*! Free the iofd |
| 479 | * |
| 480 | * This function is safe to use in the read/write callbacks and will defer freeing it until safe to do so. |
| 481 | * The iofd will be closed before. |
| 482 | * \param[in] iofd the file descriptor |
| 483 | */ |
| 484 | void osmo_iofd_free(struct osmo_io_fd *iofd) |
| 485 | { |
| 486 | if (!iofd) |
| 487 | return; |
| 488 | |
| 489 | osmo_iofd_close(iofd); |
| 490 | |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 491 | if (!IOFD_FLAG_ISSET(iofd, IOFD_FLAG_IN_CALLBACK)) { |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 492 | talloc_free(iofd); |
| 493 | } else { |
| 494 | /* Prevent our parent context from freeing us prematurely */ |
| 495 | talloc_steal(NULL, iofd); |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 496 | IOFD_FLAG_SET(iofd, IOFD_FLAG_TO_FREE); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 497 | } |
| 498 | } |
| 499 | |
| 500 | /*! Close the iofd |
| 501 | * |
| 502 | * This function closes the underlying fd and clears any messages in the tx queue |
| 503 | * The iofd is not freed and can be assigned a new file descriptor with osmo_iofd_register() |
| 504 | * \param[in] iofd the file descriptor |
| 505 | * \ returns 0 on success, a negative value otherwise |
| 506 | */ |
| 507 | int osmo_iofd_close(struct osmo_io_fd *iofd) |
| 508 | { |
| 509 | int rc = 0; |
| 510 | |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 511 | if (IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 512 | return rc; |
| 513 | |
Daniel Willmann | f89162f | 2023-06-26 19:24:46 +0200 | [diff] [blame] | 514 | IOFD_FLAG_SET(iofd, IOFD_FLAG_CLOSED); |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 515 | |
| 516 | /* Free pending msgs in tx queue */ |
| 517 | osmo_iofd_txqueue_clear(iofd); |
| 518 | msgb_free(iofd->pending); |
| 519 | |
| 520 | iofd->pending = NULL; |
| 521 | |
| 522 | if (osmo_iofd_ops.close) |
| 523 | rc = osmo_iofd_ops.close(iofd); |
| 524 | iofd->fd = -1; |
| 525 | return rc; |
| 526 | } |
| 527 | |
| 528 | /*! Set the size and headroom of the msgb allocated when receiving messages |
| 529 | * \param[in] size the size of the msgb when receiving data |
| 530 | * \param[in] headroom the headroom of the msgb when receiving data |
| 531 | */ |
| 532 | void osmo_iofd_set_alloc_info(struct osmo_io_fd *iofd, unsigned int size, unsigned int headroom) |
| 533 | { |
| 534 | iofd->msgb_alloc.headroom = headroom; |
| 535 | iofd->msgb_alloc.size = size; |
| 536 | } |
| 537 | |
| 538 | /*! Get the associated user-data from an iofd |
| 539 | * \param[in] iofd the file descriptor |
| 540 | * \returns the data that was previously set with \ref osmo_iofd_setup() |
| 541 | */ |
| 542 | void *osmo_iofd_get_data(const struct osmo_io_fd *iofd) |
| 543 | { |
| 544 | return iofd->data; |
| 545 | } |
| 546 | |
| 547 | /*! Set the associated user-data from an iofd |
| 548 | * \param[in] iofd the file descriptor |
| 549 | * \param[in] data the data to set |
| 550 | */ |
| 551 | void osmo_iofd_set_data(struct osmo_io_fd *iofd, void *data) |
| 552 | { |
| 553 | iofd->data = data; |
| 554 | } |
| 555 | |
| 556 | /*! Get the private number from an iofd |
| 557 | * \param[in] iofd the file descriptor |
| 558 | * \returns the private number that was previously set with \ref osmo_iofd_set_priv_nr() |
| 559 | */ |
| 560 | unsigned int osmo_iofd_get_priv_nr(const struct osmo_io_fd *iofd) |
| 561 | { |
| 562 | return iofd->priv_nr; |
| 563 | } |
| 564 | |
| 565 | /*! Set the private number from an iofd |
| 566 | * \param[in] iofd the file descriptor |
| 567 | * \param[in] priv_nr the private number to set |
| 568 | */ |
| 569 | void osmo_iofd_set_priv_nr(struct osmo_io_fd *iofd, unsigned int priv_nr) |
| 570 | { |
| 571 | iofd->priv_nr = priv_nr; |
| 572 | } |
| 573 | |
| 574 | /*! Get the underlying file descriptor from an iofd |
| 575 | * \param[in] iofd the file descriptor |
| 576 | * \returns the underlying file descriptor number */ |
| 577 | int osmo_iofd_get_fd(const struct osmo_io_fd *iofd) |
| 578 | { |
| 579 | return iofd->fd; |
| 580 | } |
| 581 | |
| 582 | /*! Get the name of the file descriptor |
| 583 | * \param[in] iofd the file descriptor |
| 584 | * \returns the name of the iofd as given in \ref osmo_iofd_setup() */ |
| 585 | const char *osmo_iofd_get_name(const struct osmo_io_fd *iofd) |
| 586 | { |
| 587 | return iofd->name; |
| 588 | } |
| 589 | |
Pau Espin Pedrol | 63e45e6 | 2023-06-16 16:19:45 +0200 | [diff] [blame] | 590 | /*! Set the name of the file descriptor |
| 591 | * \param[in] iofd the file descriptor |
| 592 | * \param[in] name the name to set on the file descriptor */ |
| 593 | void osmo_iofd_set_name(struct osmo_io_fd *iofd, const char *name) |
| 594 | { |
| 595 | osmo_talloc_replace_string(iofd, &iofd->name, name); |
| 596 | } |
| 597 | |
arehbein | 0c374c6 | 2023-05-14 21:43:11 +0200 | [diff] [blame] | 598 | /*! Set the osmo_io_ops for an iofd |
| 599 | * \param[in] iofd Target iofd file descriptor |
| 600 | * \param[in] ioops osmo_io_ops structure to be set */ |
| 601 | void osmo_iofd_set_ioops(struct osmo_io_fd *iofd, const struct osmo_io_ops *ioops) |
| 602 | { |
| 603 | iofd->io_ops = *ioops; |
| 604 | } |
| 605 | |
Harald Welte | 8857f3b | 2022-11-18 13:54:44 +0100 | [diff] [blame] | 606 | #endif /* defined(__linux__) */ |