/* * Copyright (c) 2003-2006 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * File: sys/aio.h * Author: Umesh Vaishampayan [umeshv@apple.com] * 05-Feb-2003 umeshv Created. * * Header file for POSIX Asynchronous IO APIs * */ #ifndef _SYS_AIO_H_ #define _SYS_AIO_H_ #include #include #include /* * [XSI] Inclusion of the header may make visible symbols defined * in the headers , , , and . * * In our case, this is limited to struct timespec, off_t and ssize_t. */ #define __need_struct_timespec #include #ifndef _OFF_T typedef __darwin_off_t off_t; #define _OFF_T #endif #ifndef _SSIZE_T #define _SSIZE_T typedef __darwin_ssize_t ssize_t; #endif struct aiocb { int aio_fildes; /* File descriptor */ off_t aio_offset; /* File offset */ volatile void *aio_buf; /* Location of buffer */ size_t aio_nbytes; /* Length of transfer */ int aio_reqprio; /* Request priority offset */ struct sigevent aio_sigevent; /* Signal number and value */ int aio_lio_opcode; /* Operation to be performed */ }; #ifdef KERNEL struct user_aiocb { int aio_fildes; /* File descriptor */ off_t aio_offset __attribute((aligned(8))); /* File offset */ user_addr_t aio_buf __attribute((aligned(8))); /* Location of buffer */ user_size_t aio_nbytes; /* Length of transfer */ int aio_reqprio; /* Request priority offset */ struct user_sigevent aio_sigevent __attribute((aligned(8))); /* Signal number and value */ int aio_lio_opcode; /* Operation to be performed */ }; #endif // KERNEL /* * aio_cancel() return values */ /* * none of the requested operations could be canceled since they are * already complete. */ #define AIO_ALLDONE 0x1 /* all requested operations have been canceled */ #define AIO_CANCELED 0x2 /* * some of the requested operations could not be canceled since * they are in progress */ #define AIO_NOTCANCELED 0x4 /* * lio_listio operation options */ #define LIO_NOP 0x0 /* option indicating that no transfer is requested */ #define LIO_READ 0x1 /* option requesting a read */ #define LIO_WRITE 0x2 /* option requesting a write */ /* * lio_listio() modes */ /* * A lio_listio() synchronization operation indicating * that the calling thread is to continue execution while * the lio_listio() operation is being performed, and no * notification is given when the operation is complete */ #define LIO_NOWAIT 0x1 /* * A lio_listio() synchronization operation indicating * that the calling thread is to suspend until the * lio_listio() operation is complete. */ #define LIO_WAIT 0x2 /* * Maximum number of operations in single lio_listio call */ #define AIO_LISTIO_MAX 16 /* * A aio_fsync() options * that the calling thread is to continue execution while * the lio_listio() operation is being performed, and no * notification is given when the operation is complete */ #ifndef O_SYNC /* XXX investigate documentation error */ #define O_SYNC 0x0080 /* queued IO is completed as if by fsync() */ #endif #if 0 /* O_DSYNC - NOT SUPPORTED */ #define O_DSYNC 0x1 /* queued async IO is completed as if by fdatasync() */ #endif #ifndef KERNEL /* * Prototypes */ __BEGIN_DECLS /* * Attempt to cancel one or more asynchronous I/O requests currently outstanding * against file descriptor fd. The aiocbp argument points to the asynchronous I/O * control block for a particular request to be canceled. If aiocbp is NULL, then * all outstanding cancelable asynchronous I/O requests against fd shall be canceled. */ int aio_cancel( int fd, struct aiocb * aiocbp ); /* * Return the error status associated with the aiocb structure referenced by the * aiocbp argument. The error status for an asynchronous I/O operation is the errno * value that would be set by the corresponding read(), write(), or fsync() * operation. If the operation has not yet completed, then the error status shall * be equal to [EINPROGRESS]. */ int aio_error( const struct aiocb * aiocbp ); /* * Asynchronously force all I/O operations associated with the file indicated by * the file descriptor aio_fildes member of the aiocb structure referenced by the * aiocbp argument and queued at the time of the call to aio_fsync() to the * synchronized I/O completion state. The function call shall return when the * synchronization request has been initiated or queued. op O_SYNC is the only * supported opertation at this time. * The aiocbp argument refers to an asynchronous I/O control block. The aiocbp * value may be used as an argument to aio_error() and aio_return() in order to * determine the error status and return status, respectively, of the asynchronous * operation while it is proceeding. When the request is queued, the error status * for the operation is [EINPROGRESS]. When all data has been successfully * transferred, the error status shall be reset to reflect the success or failure * of the operation. */ int aio_fsync( int op, struct aiocb * aiocbp ); /* * Read aiocbp->aio_nbytes from the file associated with aiocbp->aio_fildes into * the buffer pointed to by aiocbp->aio_buf. The function call shall return when * the read request has been initiated or queued. * The aiocbp value may be used as an argument to aio_error() and aio_return() in * order to determine the error status and return status, respectively, of the * asynchronous operation while it is proceeding. If an error condition is * encountered during queuing, the function call shall return without having * initiated or queued the request. The requested operation takes place at the * absolute position in the file as given by aio_offset, as if lseek() were called * immediately prior to the operation with an offset equal to aio_offset and a * whence equal to SEEK_SET. After a successful call to enqueue an asynchronous * I/O operation, the value of the file offset for the file is unspecified. */ int aio_read( struct aiocb * aiocbp ); /* * Return the return status associated with the aiocb structure referenced by * the aiocbp argument. The return status for an asynchronous I/O operation is * the value that would be returned by the corresponding read(), write(), or * fsync() function call. If the error status for the operation is equal to * [EINPROGRESS], then the return status for the operation is undefined. The * aio_return() function may be called exactly once to retrieve the return status * of a given asynchronous operation; thereafter, if the same aiocb structure * is used in a call to aio_return() or aio_error(), an error may be returned. * When the aiocb structure referred to by aiocbp is used to submit another * asynchronous operation, then aio_return() may be successfully used to * retrieve the return status of that operation. */ ssize_t aio_return( struct aiocb * aiocbp ); /* * Suspend the calling thread until at least one of the asynchronous I/O * operations referenced by the aiocblist argument has completed, until a signal * interrupts the function, or, if timeout is not NULL, until the time * interval specified by timeout has passed. If any of the aiocb structures * in the aiocblist correspond to completed asynchronous I/O operations (that is, * the error status for the operation is not equal to [EINPROGRESS]) at the * time of the call, the function shall return without suspending the calling * thread. The aiocblist argument is an array of pointers to asynchronous I/O * control blocks. The nent argument indicates the number of elements in the * array. Each aiocb structure pointed to has been used in initiating an * asynchronous I/O request via aio_read(), aio_write(), or lio_listio(). This * array may contain NULL pointers, which are ignored. */ int aio_suspend( const struct aiocb *const aiocblist[], int nent, const struct timespec * timeoutp ) __DARWIN_ALIAS_C(aio_suspend); /* * Write aiocbp->aio_nbytes to the file associated with aiocbp->aio_fildes from * the buffer pointed to by aiocbp->aio_buf. The function shall return when the * write request has been initiated or, at a minimum, queued. * The aiocbp argument may be used as an argument to aio_error() and aio_return() * in order to determine the error status and return status, respectively, of the * asynchronous operation while it is proceeding. */ int aio_write( struct aiocb * aiocbp ); /* * Initiate a list of I/O requests with a single function call. The mode * argument takes one of the values LIO_WAIT or LIO_NOWAIT and determines whether * the function returns when the I/O operations have been completed, or as soon * as the operations have been queued. If the mode argument is LIO_WAIT, the * function shall wait until all I/O is complete and the sig argument shall be * ignored. * If the mode argument is LIO_NOWAIT, the function shall return immediately, and * asynchronous notification shall occur, according to the sig argument, when all * the I/O operations complete. If sig is NULL, then no asynchronous notification * shall occur. */ int lio_listio( int mode, struct aiocb *const aiocblist[], int nent, struct sigevent *sigp ); __END_DECLS #endif /* KERNEL */ #endif /* _SYS_AIO_H_ */