| 1 | /* |
| 2 | * QEMU I/O channels |
| 3 | * |
| 4 | * Copyright (c) 2015 Red Hat, Inc. |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | #ifndef QIO_CHANNEL_H |
| 22 | #define QIO_CHANNEL_H |
| 23 | |
| 24 | #include "qom/object.h" |
| 25 | #include "qemu/coroutine-core.h" |
| 26 | #include "qemu/aio.h" |
| 27 | |
| 28 | #define TYPE_QIO_CHANNEL "qio-channel" |
| 29 | OBJECT_DECLARE_TYPE(QIOChannel, QIOChannelClass, |
| 30 | QIO_CHANNEL) |
| 31 | |
| 32 | |
| 33 | #define QIO_CHANNEL_ERR_BLOCK -2 |
| 34 | |
| 35 | #define QIO_CHANNEL_WRITE_FLAG_ZERO_COPY 0x1 |
| 36 | |
| 37 | #define QIO_CHANNEL_READ_FLAG_MSG_PEEK 0x1 |
| 38 | #define QIO_CHANNEL_READ_FLAG_RELAXED_EOF 0x2 |
| 39 | #define QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING 0x4 |
| 40 | |
| 41 | typedef enum QIOChannelFeature QIOChannelFeature; |
| 42 | |
| 43 | enum QIOChannelFeature { |
| 44 | QIO_CHANNEL_FEATURE_FD_PASS, |
| 45 | QIO_CHANNEL_FEATURE_SHUTDOWN, |
| 46 | QIO_CHANNEL_FEATURE_LISTEN, |
| 47 | QIO_CHANNEL_FEATURE_WRITE_ZERO_COPY, |
| 48 | QIO_CHANNEL_FEATURE_READ_MSG_PEEK, |
| 49 | QIO_CHANNEL_FEATURE_SEEKABLE, |
| 50 | QIO_CHANNEL_FEATURE_CONCURRENT_IO, |
| 51 | }; |
| 52 | |
| 53 | |
| 54 | typedef enum QIOChannelShutdown QIOChannelShutdown; |
| 55 | |
| 56 | enum QIOChannelShutdown { |
| 57 | QIO_CHANNEL_SHUTDOWN_READ = 1, |
| 58 | QIO_CHANNEL_SHUTDOWN_WRITE = 2, |
| 59 | QIO_CHANNEL_SHUTDOWN_BOTH = 3, |
| 60 | }; |
| 61 | |
| 62 | typedef gboolean (*QIOChannelFunc)(QIOChannel *ioc, |
| 63 | GIOCondition condition, |
| 64 | gpointer data); |
| 65 | |
| 66 | /** |
| 67 | * QIOChannel: |
| 68 | * |
| 69 | * The QIOChannel defines the core API for a generic I/O channel |
| 70 | * class hierarchy. It is inspired by GIOChannel, but has the |
| 71 | * following differences |
| 72 | * |
| 73 | * - Use QOM to properly support arbitrary subclassing |
| 74 | * - Support use of iovecs for efficient I/O with multiple blocks |
| 75 | * - None of the character set translation, binary data exclusively |
| 76 | * - Direct support for QEMU Error object reporting |
| 77 | * - File descriptor passing |
| 78 | * |
| 79 | * This base class is abstract so cannot be instantiated. There |
| 80 | * will be subclasses for dealing with sockets, files, and higher |
| 81 | * level protocols such as TLS, WebSocket, etc. |
| 82 | */ |
| 83 | |
| 84 | struct QIOChannel { |
| 85 | Object parent; |
| 86 | unsigned int features; /* bitmask of QIOChannelFeatures */ |
| 87 | char *name; |
| 88 | AioContext *read_ctx; |
| 89 | Coroutine *read_coroutine; |
| 90 | AioContext *write_ctx; |
| 91 | Coroutine *write_coroutine; |
| 92 | bool follow_coroutine_ctx; |
| 93 | #ifdef _WIN32 |
| 94 | HANDLE event; /* For use with GSource on Win32 */ |
| 95 | #endif |
| 96 | }; |
| 97 | |
| 98 | /** |
| 99 | * QIOChannelClass: |
| 100 | * |
| 101 | * This class defines the contract that all subclasses |
| 102 | * must follow to provide specific channel implementations. |
| 103 | * The first five callbacks are mandatory to support, others |
| 104 | * provide additional optional features. |
| 105 | * |
| 106 | * Consult the corresponding public API docs for a description |
| 107 | * of the semantics of each callback. io_shutdown in particular |
| 108 | * must be thread-safe, terminate quickly and must not block. |
| 109 | */ |
| 110 | struct QIOChannelClass { |
| 111 | ObjectClass parent; |
| 112 | |
| 113 | /* Mandatory callbacks */ |
| 114 | ssize_t (*io_writev)(QIOChannel *ioc, |
| 115 | const struct iovec *iov, |
| 116 | size_t niov, |
| 117 | int *fds, |
| 118 | size_t nfds, |
| 119 | int flags, |
| 120 | Error **errp); |
| 121 | |
| 122 | /* |
| 123 | * The io_readv handler must guarantee that all |
| 124 | * incoming fds are set BLOCKING (unless |
| 125 | * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag is set) and |
| 126 | * CLOEXEC (if available). |
| 127 | * @fds and @nfds are set only on success path. Still, setting |
| 128 | * @fds and @nfds to zero is acceptable on failure path. |
| 129 | */ |
| 130 | ssize_t (*io_readv)(QIOChannel *ioc, |
| 131 | const struct iovec *iov, |
| 132 | size_t niov, |
| 133 | int **fds, |
| 134 | size_t *nfds, |
| 135 | int flags, |
| 136 | Error **errp); |
| 137 | |
| 138 | int (*io_close)(QIOChannel *ioc, |
| 139 | Error **errp); |
| 140 | GSource * (*io_create_watch)(QIOChannel *ioc, |
| 141 | GIOCondition condition); |
| 142 | int (*io_set_blocking)(QIOChannel *ioc, |
| 143 | bool enabled, |
| 144 | Error **errp); |
| 145 | |
| 146 | /* Optional callbacks */ |
| 147 | ssize_t (*io_pwritev)(QIOChannel *ioc, |
| 148 | const struct iovec *iov, |
| 149 | size_t niov, |
| 150 | off_t offset, |
| 151 | Error **errp); |
| 152 | ssize_t (*io_preadv)(QIOChannel *ioc, |
| 153 | const struct iovec *iov, |
| 154 | size_t niov, |
| 155 | off_t offset, |
| 156 | Error **errp); |
| 157 | int (*io_shutdown)(QIOChannel *ioc, |
| 158 | QIOChannelShutdown how, |
| 159 | Error **errp); |
| 160 | void (*io_set_cork)(QIOChannel *ioc, |
| 161 | bool enabled); |
| 162 | void (*io_set_delay)(QIOChannel *ioc, |
| 163 | bool enabled); |
| 164 | off_t (*io_seek)(QIOChannel *ioc, |
| 165 | off_t offset, |
| 166 | int whence, |
| 167 | Error **errp); |
| 168 | void (*io_set_aio_fd_handler)(QIOChannel *ioc, |
| 169 | AioContext *read_ctx, |
| 170 | IOHandler *io_read, |
| 171 | AioContext *write_ctx, |
| 172 | IOHandler *io_write, |
| 173 | void *opaque); |
| 174 | int (*io_flush)(QIOChannel *ioc, |
| 175 | Error **errp); |
| 176 | int (*io_peerpid)(QIOChannel *ioc, |
| 177 | unsigned int *pid, |
| 178 | Error **errp); |
| 179 | }; |
| 180 | |
| 181 | /* General I/O handling functions */ |
| 182 | |
| 183 | /** |
| 184 | * qio_channel_has_feature: |
| 185 | * @ioc: the channel object |
| 186 | * @feature: the feature to check support of |
| 187 | * |
| 188 | * Determine whether the channel implementation supports |
| 189 | * the optional feature named in @feature. |
| 190 | * |
| 191 | * Returns: true if supported, false otherwise. |
| 192 | */ |
| 193 | bool qio_channel_has_feature(QIOChannel *ioc, |
| 194 | QIOChannelFeature feature); |
| 195 | |
| 196 | /** |
| 197 | * qio_channel_set_feature: |
| 198 | * @ioc: the channel object |
| 199 | * @feature: the feature to set support for |
| 200 | * |
| 201 | * Add channel support for the feature named in @feature. |
| 202 | */ |
| 203 | void qio_channel_set_feature(QIOChannel *ioc, |
| 204 | QIOChannelFeature feature); |
| 205 | |
| 206 | /** |
| 207 | * qio_channel_set_name: |
| 208 | * @ioc: the channel object |
| 209 | * @name: the name of the channel |
| 210 | * |
| 211 | * Sets the name of the channel, which serves as an aid |
| 212 | * to debugging. The name is used when creating GSource |
| 213 | * watches for this channel. |
| 214 | */ |
| 215 | void qio_channel_set_name(QIOChannel *ioc, |
| 216 | const char *name); |
| 217 | |
| 218 | /** |
| 219 | * qio_channel_readv_full: |
| 220 | * @ioc: the channel object |
| 221 | * @iov: the array of memory regions to read data into |
| 222 | * @niov: the length of the @iov array |
| 223 | * @fds: pointer to an array that will received file handles |
| 224 | * @nfds: pointer filled with number of elements in @fds on return |
| 225 | * @flags: read flags (QIO_CHANNEL_READ_FLAG_*) |
| 226 | * @errp: pointer to a NULL-initialized error object |
| 227 | * |
| 228 | * Read data from the IO channel, storing it in the |
| 229 | * memory regions referenced by @iov. Each element |
| 230 | * in the @iov will be fully populated with data |
| 231 | * before the next one is used. The @niov parameter |
| 232 | * specifies the total number of elements in @iov. |
| 233 | * |
| 234 | * It is not required for all @iov to be filled with |
| 235 | * data. If the channel is in blocking mode, at least |
| 236 | * one byte of data will be read, but no more is |
| 237 | * guaranteed. If the channel is non-blocking and no |
| 238 | * data is available, it will return QIO_CHANNEL_ERR_BLOCK |
| 239 | * |
| 240 | * If the channel has passed any file descriptors, |
| 241 | * the @fds array pointer will be allocated and |
| 242 | * the elements filled with the received file |
| 243 | * descriptors. The @nfds pointer will be updated |
| 244 | * to indicate the size of the @fds array that |
| 245 | * was allocated. It is the callers responsibility |
| 246 | * to call close() on each file descriptor and to |
| 247 | * call g_free() on the array pointer in @fds. |
| 248 | * @fds allocated and set (and @nfds is set too) |
| 249 | * _only_ on success path. Still, @fds and @nfds |
| 250 | * may be set to zero on failure path. |
| 251 | * qio_channel_readv_full() guarantees that all |
| 252 | * incoming fds are set BLOCKING (unless |
| 253 | * QIO_CHANNEL_READ_FLAG_FD_PRESERVE_BLOCKING flag |
| 254 | * is set) and CLOEXEC (if available). |
| 255 | * |
| 256 | * It is an error to pass a non-NULL @fds parameter |
| 257 | * unless qio_channel_has_feature() returns a true |
| 258 | * value for the QIO_CHANNEL_FEATURE_FD_PASS constant. |
| 259 | * |
| 260 | * Returns: the number of bytes read, or -1 on error, |
| 261 | * or QIO_CHANNEL_ERR_BLOCK if no data is available |
| 262 | * and the channel is non-blocking |
| 263 | */ |
| 264 | ssize_t qio_channel_readv_full(QIOChannel *ioc, |
| 265 | const struct iovec *iov, |
| 266 | size_t niov, |
| 267 | int **fds, |
| 268 | size_t *nfds, |
| 269 | int flags, |
| 270 | Error **errp); |
| 271 | |
| 272 | |
| 273 | /** |
| 274 | * qio_channel_writev_full: |
| 275 | * @ioc: the channel object |
| 276 | * @iov: the array of memory regions to write data from |
| 277 | * @niov: the length of the @iov array |
| 278 | * @fds: an array of file handles to send |
| 279 | * @nfds: number of file handles in @fds |
| 280 | * @flags: write flags (QIO_CHANNEL_WRITE_FLAG_*) |
| 281 | * @errp: pointer to a NULL-initialized error object |
| 282 | * |
| 283 | * Write data to the IO channel, reading it from the |
| 284 | * memory regions referenced by @iov. Each element |
| 285 | * in the @iov will be fully sent, before the next |
| 286 | * one is used. The @niov parameter specifies the |
| 287 | * total number of elements in @iov. |
| 288 | * |
| 289 | * It is not required for all @iov data to be fully |
| 290 | * sent. If the channel is in blocking mode, at least |
| 291 | * one byte of data will be sent, but no more is |
| 292 | * guaranteed. If the channel is non-blocking and no |
| 293 | * data can be sent, it will return QIO_CHANNEL_ERR_BLOCK |
| 294 | * |
| 295 | * If there are file descriptors to send, the @fds |
| 296 | * array should be non-NULL and provide the handles. |
| 297 | * All file descriptors will be sent if at least one |
| 298 | * byte of data was sent. |
| 299 | * |
| 300 | * It is an error to pass a non-NULL @fds parameter |
| 301 | * unless qio_channel_has_feature() returns a true |
| 302 | * value for the QIO_CHANNEL_FEATURE_FD_PASS constant. |
| 303 | * |
| 304 | * Returns: the number of bytes sent, or -1 on error, |
| 305 | * or QIO_CHANNEL_ERR_BLOCK if no data is can be sent |
| 306 | * and the channel is non-blocking |
| 307 | */ |
| 308 | ssize_t qio_channel_writev_full(QIOChannel *ioc, |
| 309 | const struct iovec *iov, |
| 310 | size_t niov, |
| 311 | int *fds, |
| 312 | size_t nfds, |
| 313 | int flags, |
| 314 | Error **errp); |
| 315 | |
| 316 | /** |
| 317 | * qio_channel_readv_all_eof: |
| 318 | * @ioc: the channel object |
| 319 | * @iov: the array of memory regions to read data into |
| 320 | * @niov: the length of the @iov array |
| 321 | * @errp: pointer to a NULL-initialized error object |
| 322 | * |
| 323 | * Read data from the IO channel, storing it in the |
| 324 | * memory regions referenced by @iov. Each element |
| 325 | * in the @iov will be fully populated with data |
| 326 | * before the next one is used. The @niov parameter |
| 327 | * specifies the total number of elements in @iov. |
| 328 | * |
| 329 | * The function will wait for all requested data |
| 330 | * to be read, yielding from the current coroutine |
| 331 | * if required. |
| 332 | * |
| 333 | * If end-of-file occurs before any data is read, |
| 334 | * no error is reported; otherwise, if it occurs |
| 335 | * before all requested data has been read, an error |
| 336 | * will be reported. |
| 337 | * |
| 338 | * Returns: 1 if all bytes were read, 0 if end-of-file |
| 339 | * occurs without data, or -1 on error |
| 340 | */ |
| 341 | int coroutine_mixed_fn qio_channel_readv_all_eof(QIOChannel *ioc, |
| 342 | const struct iovec *iov, |
| 343 | size_t niov, |
| 344 | Error **errp); |
| 345 | |
| 346 | /** |
| 347 | * qio_channel_readv_all: |
| 348 | * @ioc: the channel object |
| 349 | * @iov: the array of memory regions to read data into |
| 350 | * @niov: the length of the @iov array |
| 351 | * @errp: pointer to a NULL-initialized error object |
| 352 | * |
| 353 | * Read data from the IO channel, storing it in the |
| 354 | * memory regions referenced by @iov. Each element |
| 355 | * in the @iov will be fully populated with data |
| 356 | * before the next one is used. The @niov parameter |
| 357 | * specifies the total number of elements in @iov. |
| 358 | * |
| 359 | * The function will wait for all requested data |
| 360 | * to be read, yielding from the current coroutine |
| 361 | * if required. |
| 362 | * |
| 363 | * If end-of-file occurs before all requested data |
| 364 | * has been read, an error will be reported. |
| 365 | * |
| 366 | * Returns: 0 if all bytes were read, or -1 on error |
| 367 | */ |
| 368 | int coroutine_mixed_fn qio_channel_readv_all(QIOChannel *ioc, |
| 369 | const struct iovec *iov, |
| 370 | size_t niov, |
| 371 | Error **errp); |
| 372 | |
| 373 | |
| 374 | /** |
| 375 | * qio_channel_writev_all: |
| 376 | * @ioc: the channel object |
| 377 | * @iov: the array of memory regions to write data from |
| 378 | * @niov: the length of the @iov array |
| 379 | * @errp: pointer to a NULL-initialized error object |
| 380 | * |
| 381 | * Write data to the IO channel, reading it from the |
| 382 | * memory regions referenced by @iov. Each element |
| 383 | * in the @iov will be fully sent, before the next |
| 384 | * one is used. The @niov parameter specifies the |
| 385 | * total number of elements in @iov. |
| 386 | * |
| 387 | * The function will wait for all requested data |
| 388 | * to be written, yielding from the current coroutine |
| 389 | * if required. |
| 390 | * |
| 391 | * Returns: 0 if all bytes were written, or -1 on error |
| 392 | */ |
| 393 | int coroutine_mixed_fn qio_channel_writev_all(QIOChannel *ioc, |
| 394 | const struct iovec *iov, |
| 395 | size_t niov, |
| 396 | Error **errp); |
| 397 | |
| 398 | /** |
| 399 | * qio_channel_readv: |
| 400 | * @ioc: the channel object |
| 401 | * @iov: the array of memory regions to read data into |
| 402 | * @niov: the length of the @iov array |
| 403 | * @errp: pointer to a NULL-initialized error object |
| 404 | * |
| 405 | * Behaves as qio_channel_readv_full() but does not support |
| 406 | * receiving of file handles. |
| 407 | */ |
| 408 | ssize_t qio_channel_readv(QIOChannel *ioc, |
| 409 | const struct iovec *iov, |
| 410 | size_t niov, |
| 411 | Error **errp); |
| 412 | |
| 413 | /** |
| 414 | * qio_channel_writev: |
| 415 | * @ioc: the channel object |
| 416 | * @iov: the array of memory regions to write data from |
| 417 | * @niov: the length of the @iov array |
| 418 | * @errp: pointer to a NULL-initialized error object |
| 419 | * |
| 420 | * Behaves as qio_channel_writev_full() but does not support |
| 421 | * sending of file handles. |
| 422 | */ |
| 423 | ssize_t qio_channel_writev(QIOChannel *ioc, |
| 424 | const struct iovec *iov, |
| 425 | size_t niov, |
| 426 | Error **errp); |
| 427 | |
| 428 | /** |
| 429 | * qio_channel_read: |
| 430 | * @ioc: the channel object |
| 431 | * @buf: the memory region to read data into |
| 432 | * @buflen: the length of @buf |
| 433 | * @errp: pointer to a NULL-initialized error object |
| 434 | * |
| 435 | * Behaves as qio_channel_readv_full() but does not support |
| 436 | * receiving of file handles, and only supports reading into |
| 437 | * a single memory region. |
| 438 | */ |
| 439 | ssize_t qio_channel_read(QIOChannel *ioc, |
| 440 | void *buf, |
| 441 | size_t buflen, |
| 442 | Error **errp); |
| 443 | |
| 444 | /** |
| 445 | * qio_channel_write: |
| 446 | * @ioc: the channel object |
| 447 | * @buf: the memory regions to send data from |
| 448 | * @buflen: the length of @buf |
| 449 | * @errp: pointer to a NULL-initialized error object |
| 450 | * |
| 451 | * Behaves as qio_channel_writev_full() but does not support |
| 452 | * sending of file handles, and only supports writing from a |
| 453 | * single memory region. |
| 454 | */ |
| 455 | ssize_t qio_channel_write(QIOChannel *ioc, |
| 456 | const void *buf, |
| 457 | size_t buflen, |
| 458 | Error **errp); |
| 459 | |
| 460 | /** |
| 461 | * qio_channel_read_all_eof: |
| 462 | * @ioc: the channel object |
| 463 | * @buf: the memory region to read data into |
| 464 | * @buflen: the number of bytes to @buf |
| 465 | * @errp: pointer to a NULL-initialized error object |
| 466 | * |
| 467 | * Reads @buflen bytes into @buf, possibly blocking or (if the |
| 468 | * channel is non-blocking) yielding from the current coroutine |
| 469 | * multiple times until the entire content is read. If end-of-file |
| 470 | * occurs immediately it is not an error, but if it occurs after |
| 471 | * data has been read it will return an error rather than a |
| 472 | * short-read. Otherwise behaves as qio_channel_read(). |
| 473 | * |
| 474 | * Returns: 1 if all bytes were read, 0 if end-of-file occurs |
| 475 | * without data, or -1 on error |
| 476 | */ |
| 477 | int coroutine_mixed_fn qio_channel_read_all_eof(QIOChannel *ioc, |
| 478 | void *buf, |
| 479 | size_t buflen, |
| 480 | Error **errp); |
| 481 | |
| 482 | /** |
| 483 | * qio_channel_read_all: |
| 484 | * @ioc: the channel object |
| 485 | * @buf: the memory region to read data into |
| 486 | * @buflen: the number of bytes to @buf |
| 487 | * @errp: pointer to a NULL-initialized error object |
| 488 | * |
| 489 | * Reads @buflen bytes into @buf, possibly blocking or (if the |
| 490 | * channel is non-blocking) yielding from the current coroutine |
| 491 | * multiple times until the entire content is read. If end-of-file |
| 492 | * occurs it will return an error rather than a short-read. Otherwise |
| 493 | * behaves as qio_channel_read(). |
| 494 | * |
| 495 | * Returns: 0 if all bytes were read, or -1 on error |
| 496 | */ |
| 497 | int coroutine_mixed_fn qio_channel_read_all(QIOChannel *ioc, |
| 498 | void *buf, |
| 499 | size_t buflen, |
| 500 | Error **errp); |
| 501 | |
| 502 | /** |
| 503 | * qio_channel_write_all: |
| 504 | * @ioc: the channel object |
| 505 | * @buf: the memory region to write data into |
| 506 | * @buflen: the number of bytes to @buf |
| 507 | * @errp: pointer to a NULL-initialized error object |
| 508 | * |
| 509 | * Writes @buflen bytes from @buf, possibly blocking or (if the |
| 510 | * channel is non-blocking) yielding from the current coroutine |
| 511 | * multiple times until the entire content is written. Otherwise |
| 512 | * behaves as qio_channel_write(). |
| 513 | * |
| 514 | * Returns: 0 if all bytes were written, or -1 on error |
| 515 | */ |
| 516 | int coroutine_mixed_fn qio_channel_write_all(QIOChannel *ioc, |
| 517 | const void *buf, |
| 518 | size_t buflen, |
| 519 | Error **errp); |
| 520 | |
| 521 | /** |
| 522 | * qio_channel_set_blocking: |
| 523 | * @ioc: the channel object |
| 524 | * @enabled: the blocking flag state |
| 525 | * @errp: pointer to a NULL-initialized error object |
| 526 | * |
| 527 | * If @enabled is true, then the channel is put into |
| 528 | * blocking mode, otherwise it will be non-blocking. |
| 529 | * |
| 530 | * In non-blocking mode, read/write operations may |
| 531 | * return QIO_CHANNEL_ERR_BLOCK if they would otherwise |
| 532 | * block on I/O |
| 533 | */ |
| 534 | bool qio_channel_set_blocking(QIOChannel *ioc, |
| 535 | bool enabled, |
| 536 | Error **errp); |
| 537 | |
| 538 | /** |
| 539 | * qio_channel_set_follow_coroutine_ctx: |
| 540 | * @ioc: the channel object |
| 541 | * @enabled: whether or not to follow the coroutine's AioContext |
| 542 | * |
| 543 | * If @enabled is true, calls to qio_channel_yield() use the current |
| 544 | * coroutine's AioContext. Usually this is desirable. |
| 545 | * |
| 546 | * If @enabled is false, calls to qio_channel_yield() use the global iohandler |
| 547 | * AioContext. This is may be used by coroutines that run in the main loop and |
| 548 | * do not wish to respond to I/O during nested event loops. This is the |
| 549 | * default for compatibility with code that is not aware of AioContexts. |
| 550 | */ |
| 551 | void qio_channel_set_follow_coroutine_ctx(QIOChannel *ioc, bool enabled); |
| 552 | |
| 553 | /** |
| 554 | * qio_channel_close: |
| 555 | * @ioc: the channel object |
| 556 | * @errp: pointer to a NULL-initialized error object |
| 557 | * |
| 558 | * Close the channel, flushing any pending I/O |
| 559 | * |
| 560 | * Returns: 0 on success, -1 on error |
| 561 | */ |
| 562 | int qio_channel_close(QIOChannel *ioc, |
| 563 | Error **errp); |
| 564 | |
| 565 | /** |
| 566 | * qio_channel_pwritev |
| 567 | * @ioc: the channel object |
| 568 | * @iov: the array of memory regions to write data from |
| 569 | * @niov: the length of the @iov array |
| 570 | * @offset: offset in the channel where writes should begin |
| 571 | * @errp: pointer to a NULL-initialized error object |
| 572 | * |
| 573 | * Not all implementations will support this facility, so may report |
| 574 | * an error. To avoid errors, the caller may check for the feature |
| 575 | * flag QIO_CHANNEL_FEATURE_SEEKABLE prior to calling this method. |
| 576 | * |
| 577 | * Behaves as qio_channel_writev_full, apart from not supporting |
| 578 | * sending of file handles as well as beginning the write at the |
| 579 | * passed @offset |
| 580 | * |
| 581 | */ |
| 582 | ssize_t qio_channel_pwritev(QIOChannel *ioc, const struct iovec *iov, |
| 583 | size_t niov, off_t offset, Error **errp); |
| 584 | |
| 585 | /** |
| 586 | * qio_channel_pwrite |
| 587 | * @ioc: the channel object |
| 588 | * @buf: the memory region to write data into |
| 589 | * @buflen: the number of bytes to @buf |
| 590 | * @offset: offset in the channel where writes should begin |
| 591 | * @errp: pointer to a NULL-initialized error object |
| 592 | * |
| 593 | * Not all implementations will support this facility, so may report |
| 594 | * an error. To avoid errors, the caller may check for the feature |
| 595 | * flag QIO_CHANNEL_FEATURE_SEEKABLE prior to calling this method. |
| 596 | * |
| 597 | */ |
| 598 | ssize_t qio_channel_pwrite(QIOChannel *ioc, void *buf, size_t buflen, |
| 599 | off_t offset, Error **errp); |
| 600 | |
| 601 | /** |
| 602 | * qio_channel_pwritev_all: |
| 603 | * @ioc: the channel object |
| 604 | * @iov: the array of memory regions to write data from |
| 605 | * @niov: the length of the @iov array |
| 606 | * @offset: the starting offset in the channel to write to |
| 607 | * @errp: pointer to a NULL-initialized error object |
| 608 | * |
| 609 | * Writes @iov, possibly blocking or (if the channel is non-blocking) |
| 610 | * yielding from the current coroutine multiple times until the entire |
| 611 | * content is written. Otherwise behaves as qio_channel_pwritev(). |
| 612 | * |
| 613 | * Returns: 0 if all bytes were written, or -1 on error |
| 614 | */ |
| 615 | int coroutine_mixed_fn qio_channel_pwritev_all(QIOChannel *ioc, |
| 616 | const struct iovec *iov, |
| 617 | size_t niov, |
| 618 | off_t offset, |
| 619 | Error **errp); |
| 620 | |
| 621 | /** |
| 622 | * qio_channel_pwrite_all: |
| 623 | * @ioc: the channel object |
| 624 | * @buf: the memory region to write data from |
| 625 | * @buflen: the number of bytes to write from @buf |
| 626 | * @offset: the starting offset in the channel to write to |
| 627 | * @errp: pointer to a NULL-initialized error object |
| 628 | * |
| 629 | * Writes @buflen bytes from @buf, possibly blocking or (if the |
| 630 | * channel is non-blocking) yielding from the current coroutine |
| 631 | * multiple times until the entire content is written. Otherwise |
| 632 | * behaves as qio_channel_pwrite(). |
| 633 | * |
| 634 | * Returns: 0 if all bytes were written, or -1 on error |
| 635 | */ |
| 636 | int coroutine_mixed_fn qio_channel_pwrite_all(QIOChannel *ioc, |
| 637 | const void *buf, |
| 638 | size_t buflen, |
| 639 | off_t offset, |
| 640 | Error **errp); |
| 641 | |
| 642 | /** |
| 643 | * qio_channel_preadv |
| 644 | * @ioc: the channel object |
| 645 | * @iov: the array of memory regions to read data into |
| 646 | * @niov: the length of the @iov array |
| 647 | * @offset: offset in the channel where writes should begin |
| 648 | * @errp: pointer to a NULL-initialized error object |
| 649 | * |
| 650 | * Not all implementations will support this facility, so may report |
| 651 | * an error. To avoid errors, the caller may check for the feature |
| 652 | * flag QIO_CHANNEL_FEATURE_SEEKABLE prior to calling this method. |
| 653 | * |
| 654 | * Behaves as qio_channel_readv_full, apart from not supporting |
| 655 | * receiving of file handles as well as beginning the read at the |
| 656 | * passed @offset |
| 657 | * |
| 658 | */ |
| 659 | ssize_t qio_channel_preadv(QIOChannel *ioc, const struct iovec *iov, |
| 660 | size_t niov, off_t offset, Error **errp); |
| 661 | |
| 662 | /** |
| 663 | * qio_channel_pread |
| 664 | * @ioc: the channel object |
| 665 | * @buf: the memory region to write data into |
| 666 | * @buflen: the number of bytes to @buf |
| 667 | * @offset: offset in the channel where writes should begin |
| 668 | * @errp: pointer to a NULL-initialized error object |
| 669 | * |
| 670 | * Not all implementations will support this facility, so may report |
| 671 | * an error. To avoid errors, the caller may check for the feature |
| 672 | * flag QIO_CHANNEL_FEATURE_SEEKABLE prior to calling this method. |
| 673 | * |
| 674 | */ |
| 675 | ssize_t qio_channel_pread(QIOChannel *ioc, void *buf, size_t buflen, |
| 676 | off_t offset, Error **errp); |
| 677 | |
| 678 | /** |
| 679 | * qio_channel_preadv_all_eof: |
| 680 | * @ioc: the channel object |
| 681 | * @iov: the array of memory regions to read data into |
| 682 | * @niov: the length of the @iov array |
| 683 | * @offset: the starting offset in the channel to read from |
| 684 | * @errp: pointer to a NULL-initialized error object |
| 685 | * |
| 686 | * Reads @iov, possibly blocking or (if the channel is non-blocking) |
| 687 | * yielding from the current coroutine multiple times until the entire |
| 688 | * content is read. If end-of-file occurs immediately it is not an |
| 689 | * error, but if it occurs after data has been read it will return |
| 690 | * an error rather than a short-read. Otherwise behaves as |
| 691 | * qio_channel_preadv(). |
| 692 | * |
| 693 | * Returns: 1 if all bytes were read, 0 if end-of-file occurs |
| 694 | * without data, or -1 on error |
| 695 | */ |
| 696 | int coroutine_mixed_fn qio_channel_preadv_all_eof(QIOChannel *ioc, |
| 697 | const struct iovec *iov, |
| 698 | size_t niov, |
| 699 | off_t offset, |
| 700 | Error **errp); |
| 701 | |
| 702 | /** |
| 703 | * qio_channel_preadv_all: |
| 704 | * @ioc: the channel object |
| 705 | * @iov: the array of memory regions to read data into |
| 706 | * @niov: the length of the @iov array |
| 707 | * @offset: the starting offset in the channel to read from |
| 708 | * @errp: pointer to a NULL-initialized error object |
| 709 | * |
| 710 | * Reads @iov, possibly blocking or (if the channel is non-blocking) |
| 711 | * yielding from the current coroutine multiple times until the entire |
| 712 | * content is read. If end-of-file occurs before all requested data |
| 713 | * has been read, an error will be reported. Otherwise behaves as |
| 714 | * qio_channel_preadv(). |
| 715 | * |
| 716 | * Returns: 0 if all bytes were read, or -1 on error |
| 717 | */ |
| 718 | int coroutine_mixed_fn qio_channel_preadv_all(QIOChannel *ioc, |
| 719 | const struct iovec *iov, |
| 720 | size_t niov, |
| 721 | off_t offset, |
| 722 | Error **errp); |
| 723 | |
| 724 | /** |
| 725 | * qio_channel_pread_all_eof: |
| 726 | * @ioc: the channel object |
| 727 | * @buf: the memory region to read data into |
| 728 | * @buflen: the number of bytes to read into @buf |
| 729 | * @offset: the starting offset in the channel to read from |
| 730 | * @errp: pointer to a NULL-initialized error object |
| 731 | * |
| 732 | * Reads @buflen bytes, possibly blocking or (if the channel is |
| 733 | * non-blocking) yielding from the current coroutine multiple times |
| 734 | * until the entire content is read. If end-of-file occurs |
| 735 | * immediately it is not an error, but if it occurs after data has |
| 736 | * been read it will return an error rather than a short-read. |
| 737 | * Otherwise behaves as qio_channel_pread(). |
| 738 | * |
| 739 | * Returns: 1 if all bytes were read, 0 if end-of-file occurs |
| 740 | * without data, or -1 on error |
| 741 | */ |
| 742 | int coroutine_mixed_fn qio_channel_pread_all_eof(QIOChannel *ioc, |
| 743 | void *buf, |
| 744 | size_t buflen, |
| 745 | off_t offset, |
| 746 | Error **errp); |
| 747 | |
| 748 | /** |
| 749 | * qio_channel_pread_all: |
| 750 | * @ioc: the channel object |
| 751 | * @buf: the memory region to read data into |
| 752 | * @buflen: the number of bytes to read into @buf |
| 753 | * @offset: the starting offset in the channel to read from |
| 754 | * @errp: pointer to a NULL-initialized error object |
| 755 | * |
| 756 | * Reads @buflen bytes, possibly blocking or (if the channel is |
| 757 | * non-blocking) yielding from the current coroutine multiple times |
| 758 | * until the entire content is read. If end-of-file occurs before |
| 759 | * all requested data has been read, an error will be reported. |
| 760 | * Otherwise behaves as qio_channel_pread(). |
| 761 | * |
| 762 | * Returns: 0 if all bytes were read, or -1 on error |
| 763 | */ |
| 764 | int coroutine_mixed_fn qio_channel_pread_all(QIOChannel *ioc, |
| 765 | void *buf, |
| 766 | size_t buflen, |
| 767 | off_t offset, |
| 768 | Error **errp); |
| 769 | |
| 770 | /** |
| 771 | * qio_channel_shutdown: |
| 772 | * @ioc: the channel object |
| 773 | * @how: the direction to shutdown |
| 774 | * @errp: pointer to a NULL-initialized error object |
| 775 | * |
| 776 | * Shutdowns transmission and/or receiving of data |
| 777 | * without closing the underlying transport. |
| 778 | * |
| 779 | * Not all implementations will support this facility, |
| 780 | * so may report an error. To avoid errors, the |
| 781 | * caller may check for the feature flag |
| 782 | * QIO_CHANNEL_FEATURE_SHUTDOWN prior to calling |
| 783 | * this method. |
| 784 | * |
| 785 | * This function is thread-safe, terminates quickly and does not block. |
| 786 | * |
| 787 | * Returns: 0 on success, -1 on error |
| 788 | */ |
| 789 | int qio_channel_shutdown(QIOChannel *ioc, |
| 790 | QIOChannelShutdown how, |
| 791 | Error **errp); |
| 792 | |
| 793 | /** |
| 794 | * qio_channel_set_delay: |
| 795 | * @ioc: the channel object |
| 796 | * @enabled: the new flag state |
| 797 | * |
| 798 | * Controls whether the underlying transport is |
| 799 | * permitted to delay writes in order to merge |
| 800 | * small packets. If @enabled is true, then the |
| 801 | * writes may be delayed in order to opportunistically |
| 802 | * merge small packets into larger ones. If @enabled |
| 803 | * is false, writes are dispatched immediately with |
| 804 | * no delay. |
| 805 | * |
| 806 | * When @enabled is false, applications may wish to |
| 807 | * use the qio_channel_set_cork() method to explicitly |
| 808 | * control write merging. |
| 809 | * |
| 810 | * On channels which are backed by a socket, this |
| 811 | * API corresponds to the inverse of TCP_NODELAY flag, |
| 812 | * controlling whether the Nagle algorithm is active. |
| 813 | * |
| 814 | * This setting is merely a hint, so implementations are |
| 815 | * free to ignore this without it being considered an |
| 816 | * error. |
| 817 | */ |
| 818 | void qio_channel_set_delay(QIOChannel *ioc, |
| 819 | bool enabled); |
| 820 | |
| 821 | /** |
| 822 | * qio_channel_set_cork: |
| 823 | * @ioc: the channel object |
| 824 | * @enabled: the new flag state |
| 825 | * |
| 826 | * Controls whether the underlying transport is |
| 827 | * permitted to dispatch data that is written. |
| 828 | * If @enabled is true, then any data written will |
| 829 | * be queued in local buffers until @enabled is |
| 830 | * set to false once again. |
| 831 | * |
| 832 | * This feature is typically used when the automatic |
| 833 | * write coalescing facility is disabled via the |
| 834 | * qio_channel_set_delay() method. |
| 835 | * |
| 836 | * On channels which are backed by a socket, this |
| 837 | * API corresponds to the TCP_CORK flag. |
| 838 | * |
| 839 | * This setting is merely a hint, so implementations are |
| 840 | * free to ignore this without it being considered an |
| 841 | * error. |
| 842 | */ |
| 843 | void qio_channel_set_cork(QIOChannel *ioc, |
| 844 | bool enabled); |
| 845 | |
| 846 | |
| 847 | /** |
| 848 | * qio_channel_seek: |
| 849 | * @ioc: the channel object |
| 850 | * @offset: the position to seek to, relative to @whence |
| 851 | * @whence: one of the (POSIX) SEEK_* constants listed below |
| 852 | * @errp: pointer to a NULL-initialized error object |
| 853 | * |
| 854 | * Moves the current I/O position within the channel |
| 855 | * @ioc, to be @offset. The value of @offset is |
| 856 | * interpreted relative to @whence: |
| 857 | * |
| 858 | * SEEK_SET - the position is set to @offset bytes |
| 859 | * SEEK_CUR - the position is moved by @offset bytes |
| 860 | * SEEK_END - the position is set to end of the file plus @offset bytes |
| 861 | * |
| 862 | * Not all implementations will support this facility, |
| 863 | * so may report an error. |
| 864 | * |
| 865 | * Returns: the new position on success, (off_t)-1 on failure |
| 866 | */ |
| 867 | off_t qio_channel_io_seek(QIOChannel *ioc, |
| 868 | off_t offset, |
| 869 | int whence, |
| 870 | Error **errp); |
| 871 | |
| 872 | |
| 873 | /** |
| 874 | * qio_channel_create_watch: |
| 875 | * @ioc: the channel object |
| 876 | * @condition: the I/O condition to monitor |
| 877 | * |
| 878 | * Create a new main loop source that is used to watch |
| 879 | * for the I/O condition @condition. Typically the |
| 880 | * qio_channel_add_watch() method would be used instead |
| 881 | * of this, since it directly attaches a callback to |
| 882 | * the source |
| 883 | * |
| 884 | * Returns: the new main loop source. |
| 885 | */ |
| 886 | GSource *qio_channel_create_watch(QIOChannel *ioc, |
| 887 | GIOCondition condition); |
| 888 | |
| 889 | /** |
| 890 | * qio_channel_add_watch: |
| 891 | * @ioc: the channel object |
| 892 | * @condition: the I/O condition to monitor |
| 893 | * @func: callback to invoke when the source becomes ready |
| 894 | * @user_data: opaque data to pass to @func |
| 895 | * @notify: callback to free @user_data |
| 896 | * |
| 897 | * Create a new main loop source that is used to watch |
| 898 | * for the I/O condition @condition. The callback @func |
| 899 | * will be registered against the source, to be invoked |
| 900 | * when the source becomes ready. The optional @user_data |
| 901 | * will be passed to @func when it is invoked. The @notify |
| 902 | * callback will be used to free @user_data when the |
| 903 | * watch is deleted |
| 904 | * |
| 905 | * The returned source ID can be used with g_source_remove() |
| 906 | * to remove and free the source when no longer required. |
| 907 | * Alternatively the @func callback can return a FALSE |
| 908 | * value. |
| 909 | * |
| 910 | * Returns: the source ID |
| 911 | */ |
| 912 | guint qio_channel_add_watch(QIOChannel *ioc, |
| 913 | GIOCondition condition, |
| 914 | QIOChannelFunc func, |
| 915 | gpointer user_data, |
| 916 | GDestroyNotify notify); |
| 917 | |
| 918 | /** |
| 919 | * qio_channel_add_watch_full: |
| 920 | * @ioc: the channel object |
| 921 | * @condition: the I/O condition to monitor |
| 922 | * @func: callback to invoke when the source becomes ready |
| 923 | * @user_data: opaque data to pass to @func |
| 924 | * @notify: callback to free @user_data |
| 925 | * @context: the context to run the watch source |
| 926 | * |
| 927 | * Similar as qio_channel_add_watch(), but allows to specify context |
| 928 | * to run the watch source. |
| 929 | * |
| 930 | * Returns: the source ID |
| 931 | */ |
| 932 | guint qio_channel_add_watch_full(QIOChannel *ioc, |
| 933 | GIOCondition condition, |
| 934 | QIOChannelFunc func, |
| 935 | gpointer user_data, |
| 936 | GDestroyNotify notify, |
| 937 | GMainContext *context); |
| 938 | |
| 939 | /** |
| 940 | * qio_channel_add_watch_source: |
| 941 | * @ioc: the channel object |
| 942 | * @condition: the I/O condition to monitor |
| 943 | * @func: callback to invoke when the source becomes ready |
| 944 | * @user_data: opaque data to pass to @func |
| 945 | * @notify: callback to free @user_data |
| 946 | * @context: gcontext to bind the source to |
| 947 | * |
| 948 | * Similar as qio_channel_add_watch(), but allows to specify context |
| 949 | * to run the watch source, meanwhile return the GSource object |
| 950 | * instead of tag ID, with the GSource referenced already. |
| 951 | * |
| 952 | * Note: callers is responsible to unref the source when not needed. |
| 953 | * |
| 954 | * Returns: the source pointer |
| 955 | */ |
| 956 | GSource *qio_channel_add_watch_source(QIOChannel *ioc, |
| 957 | GIOCondition condition, |
| 958 | QIOChannelFunc func, |
| 959 | gpointer user_data, |
| 960 | GDestroyNotify notify, |
| 961 | GMainContext *context); |
| 962 | |
| 963 | /** |
| 964 | * qio_channel_yield: |
| 965 | * @ioc: the channel object |
| 966 | * @condition: the I/O condition to wait for |
| 967 | * |
| 968 | * Yields execution from the current coroutine until the condition |
| 969 | * indicated by @condition becomes available. @condition must |
| 970 | * be either %G_IO_IN or %G_IO_OUT; it cannot contain both. In |
| 971 | * addition, no two coroutine can be waiting on the same condition |
| 972 | * and channel at the same time. |
| 973 | * |
| 974 | * This must only be called from coroutine context. It is safe to |
| 975 | * reenter the coroutine externally while it is waiting; in this |
| 976 | * case the function will return even if @condition is not yet |
| 977 | * available. |
| 978 | */ |
| 979 | void coroutine_fn qio_channel_yield(QIOChannel *ioc, |
| 980 | GIOCondition condition); |
| 981 | |
| 982 | /** |
| 983 | * qio_channel_wake_read: |
| 984 | * @ioc: the channel object |
| 985 | * |
| 986 | * If qio_channel_yield() is currently waiting for the channel to become |
| 987 | * readable, interrupt it and reenter immediately. This function is safe to call |
| 988 | * from any thread. |
| 989 | */ |
| 990 | void qio_channel_wake_read(QIOChannel *ioc); |
| 991 | |
| 992 | /** |
| 993 | * qio_channel_wait: |
| 994 | * @ioc: the channel object |
| 995 | * @condition: the I/O condition to wait for |
| 996 | * |
| 997 | * Block execution from the current thread until |
| 998 | * the condition indicated by @condition becomes |
| 999 | * available. |
| 1000 | * |
| 1001 | * This will enter a nested event loop to perform |
| 1002 | * the wait. |
| 1003 | */ |
| 1004 | void qio_channel_wait(QIOChannel *ioc, |
| 1005 | GIOCondition condition); |
| 1006 | |
| 1007 | /** |
| 1008 | * qio_channel_wait_cond: |
| 1009 | * @ioc: the channel object |
| 1010 | * @condition: the I/O condition to wait for |
| 1011 | * |
| 1012 | * Block execution from the current thread until |
| 1013 | * the condition indicated by @condition becomes |
| 1014 | * available. |
| 1015 | * |
| 1016 | * This will work with/without a coroutine context, by automatically select |
| 1017 | * the proper API to wait. |
| 1018 | */ |
| 1019 | void coroutine_mixed_fn qio_channel_wait_cond(QIOChannel *ioc, |
| 1020 | GIOCondition condition); |
| 1021 | |
| 1022 | /** |
| 1023 | * qio_channel_set_aio_fd_handler: |
| 1024 | * @ioc: the channel object |
| 1025 | * @read_ctx: the AioContext to set the read handler on or NULL |
| 1026 | * @io_read: the read handler |
| 1027 | * @write_ctx: the AioContext to set the write handler on or NULL |
| 1028 | * @io_write: the write handler |
| 1029 | * @opaque: the opaque value passed to the handler |
| 1030 | * |
| 1031 | * This is used internally by qio_channel_yield(). It can |
| 1032 | * be used by channel implementations to forward the handlers |
| 1033 | * to another channel (e.g. from #QIOChannelTLS to the |
| 1034 | * underlying socket). |
| 1035 | * |
| 1036 | * When @read_ctx is NULL, don't touch the read handler. When @write_ctx is |
| 1037 | * NULL, don't touch the write handler. Note that setting the read handler |
| 1038 | * clears the write handler, and vice versa, if they share the same AioContext. |
| 1039 | * Therefore the caller must pass both handlers together when sharing the same |
| 1040 | * AioContext. |
| 1041 | */ |
| 1042 | void qio_channel_set_aio_fd_handler(QIOChannel *ioc, |
| 1043 | AioContext *read_ctx, |
| 1044 | IOHandler *io_read, |
| 1045 | AioContext *write_ctx, |
| 1046 | IOHandler *io_write, |
| 1047 | void *opaque); |
| 1048 | |
| 1049 | /** |
| 1050 | * qio_channel_readv_full_all_eof: |
| 1051 | * @ioc: the channel object |
| 1052 | * @iov: the array of memory regions to read data to |
| 1053 | * @niov: the length of the @iov array |
| 1054 | * @fds: an array of file handles to read |
| 1055 | * @nfds: number of file handles in @fds |
| 1056 | * @flags: read flags (QIO_CHANNEL_READ_FLAG_*) |
| 1057 | * @errp: pointer to a NULL-initialized error object |
| 1058 | * |
| 1059 | * |
| 1060 | * Performs same function as qio_channel_readv_all_eof. |
| 1061 | * Additionally, attempts to read file descriptors shared |
| 1062 | * over the channel. The function will wait for all |
| 1063 | * requested data to be read, yielding from the current |
| 1064 | * coroutine if required. data refers to both file |
| 1065 | * descriptors and the iovs. |
| 1066 | * |
| 1067 | * Returns: 1 if all bytes were read, 0 if end-of-file |
| 1068 | * occurs without data, or -1 on error |
| 1069 | */ |
| 1070 | |
| 1071 | int coroutine_mixed_fn qio_channel_readv_full_all_eof(QIOChannel *ioc, |
| 1072 | const struct iovec *iov, |
| 1073 | size_t niov, |
| 1074 | int **fds, size_t *nfds, |
| 1075 | int flags, |
| 1076 | Error **errp); |
| 1077 | |
| 1078 | /** |
| 1079 | * qio_channel_readv_full_all: |
| 1080 | * @ioc: the channel object |
| 1081 | * @iov: the array of memory regions to read data to |
| 1082 | * @niov: the length of the @iov array |
| 1083 | * @fds: an array of file handles to read |
| 1084 | * @nfds: number of file handles in @fds |
| 1085 | * @errp: pointer to a NULL-initialized error object |
| 1086 | * |
| 1087 | * |
| 1088 | * Performs same function as qio_channel_readv_all_eof. |
| 1089 | * Additionally, attempts to read file descriptors shared |
| 1090 | * over the channel. The function will wait for all |
| 1091 | * requested data to be read, yielding from the current |
| 1092 | * coroutine if required. data refers to both file |
| 1093 | * descriptors and the iovs. |
| 1094 | * |
| 1095 | * Returns: 0 if all bytes were read, or -1 on error |
| 1096 | */ |
| 1097 | |
| 1098 | int coroutine_mixed_fn qio_channel_readv_full_all(QIOChannel *ioc, |
| 1099 | const struct iovec *iov, |
| 1100 | size_t niov, |
| 1101 | int **fds, size_t *nfds, |
| 1102 | Error **errp); |
| 1103 | |
| 1104 | /** |
| 1105 | * qio_channel_writev_full_all: |
| 1106 | * @ioc: the channel object |
| 1107 | * @iov: the array of memory regions to write data from |
| 1108 | * @niov: the length of the @iov array |
| 1109 | * @fds: an array of file handles to send |
| 1110 | * @nfds: number of file handles in @fds |
| 1111 | * @flags: write flags (QIO_CHANNEL_WRITE_FLAG_*) |
| 1112 | * @errp: pointer to a NULL-initialized error object |
| 1113 | * |
| 1114 | * |
| 1115 | * Behaves like qio_channel_writev_full but will attempt |
| 1116 | * to send all data passed (file handles and memory regions). |
| 1117 | * The function will wait for all requested data |
| 1118 | * to be written, yielding from the current coroutine |
| 1119 | * if required. |
| 1120 | * |
| 1121 | * If QIO_CHANNEL_WRITE_FLAG_ZERO_COPY is passed in flags, |
| 1122 | * instead of waiting for all requested data to be written, |
| 1123 | * this function will wait until it's all queued for writing. |
| 1124 | * In this case, if the buffer gets changed between queueing and |
| 1125 | * sending, the updated buffer will be sent. If this is not a |
| 1126 | * desired behavior, it's suggested to call qio_channel_flush() |
| 1127 | * before reusing the buffer. |
| 1128 | * |
| 1129 | * Returns: 0 if all bytes were written, or -1 on error |
| 1130 | */ |
| 1131 | |
| 1132 | int coroutine_mixed_fn qio_channel_writev_full_all(QIOChannel *ioc, |
| 1133 | const struct iovec *iov, |
| 1134 | size_t niov, |
| 1135 | int *fds, size_t nfds, |
| 1136 | int flags, Error **errp); |
| 1137 | |
| 1138 | /** |
| 1139 | * qio_channel_flush: |
| 1140 | * @ioc: the channel object |
| 1141 | * @errp: pointer to a NULL-initialized error object |
| 1142 | * |
| 1143 | * Will block until every packet queued with |
| 1144 | * qio_channel_writev_full() + QIO_CHANNEL_WRITE_FLAG_ZERO_COPY |
| 1145 | * is sent, or return in case of any error. |
| 1146 | * |
| 1147 | * If not implemented, acts as a no-op, and returns 0. |
| 1148 | * |
| 1149 | * Returns -1 if any error is found, |
| 1150 | * 1 if at least one send failed to use zero copy. |
| 1151 | * 0 if every send successfully used zero copy. |
| 1152 | */ |
| 1153 | |
| 1154 | int qio_channel_flush(QIOChannel *ioc, |
| 1155 | Error **errp); |
| 1156 | |
| 1157 | /** |
| 1158 | * qio_channel_get_peercred: |
| 1159 | * @ioc: the channel object |
| 1160 | * @pid: pointer to pid |
| 1161 | * @errp: pointer to a NULL-initialized error object |
| 1162 | * |
| 1163 | * Returns the pid of the peer process connected to this socket. |
| 1164 | * |
| 1165 | * The use of this function is possible only for connected |
| 1166 | * AF_UNIX stream sockets and for AF_UNIX stream and datagram |
| 1167 | * socket pairs on Linux. |
| 1168 | * Return -1 on error with pid -1 for the non-Linux OS. |
| 1169 | * |
| 1170 | */ |
| 1171 | int qio_channel_get_peerpid(QIOChannel *ioc, |
| 1172 | unsigned int *pid, |
| 1173 | Error **errp); |
| 1174 | |
| 1175 | #endif /* QIO_CHANNEL_H */ |