rt-thread-official/components/libc/posix/io/aio/aio.c

507 lines
20 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2017/12/30 Bernard The first version.
* 2024/03/26 TroyMitchelle Added some function comments
* 2024/03/27 TroyMitchelle Fix the issue of incorrect return of invalid parameters in aio_write
*/
#include <rtthread.h>
#include <rthw.h>
#include <stdint.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/errno.h>
#include "aio.h"
struct rt_workqueue* aio_queue = NULL;
/**
* The aio_cancel() function shall attempt to cancel one or more asynchronous I/O
* requests currently outstanding against file descriptor fildes. 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 fildes shall be canceled.
*
* Normal asynchronous notification shall occur for asynchronous I/O operations
* that are successfully canceled. If there are requests that cannot be canceled,
* then the normal asynchronous completion process shall take place for those
* requests when they are completed.
*
* For requested operations that are successfully canceled, the associated error
* status shall be set to [ECANCELED] and the return status shall be -1. For
* requested operations that are not successfully canceled, the aiocbp shall not
* be modified by aio_cancel().
*
* If aiocbp is not NULL, then if fildes does not have the same value as the file
* descriptor with which the asynchronous operation was initiated, unspecified results occur.
*
* Which operations are cancelable is implementation-defined.
*/
int aio_cancel(int fd, struct aiocb *cb)
{
rt_err_t ret;
if (!cb) return -EINVAL;
if (cb->aio_fildes != fd) return -EINVAL;
ret = rt_workqueue_cancel_work_sync(aio_queue, &(cb->aio_work));
if (ret == RT_EOK)
{
errno = -ECANCELED;
return -1;
}
return 0;
}
/**
* The aio_error() function shall 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(),
*/
int aio_error(const struct aiocb *cb)
{
if (cb)
{
return cb->aio_result;
}
return -EINVAL;
}
/**
* The aio_fsync() function shall asynchronously perform a file synchronization
* operation, as specified by the op argument, for 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(). The function call shall return when the synchronization
* request has been initiated or queued to the file or device (even when the data
* cannot be synchronized immediately).
*
* option: If op is O_DSYNC, all currently queued I/O operations shall be completed
* as if by a call to fdatasync(); that is, as defined for synchronized I/O data
* integrity completion.
*
* option: If op is O_SYNC, all currently queued I/O operations shall be completed
* as if by a call to fsync(); that is, as defined for synchronized I/O file integrity
* completion. If the aio_fsync() function fails, or if the operation queued by
* aio_fsync() fails, then outstanding I/O operations are not guaranteed to have
* been completed.
*
* If aio_fsync() succeeds, then it is only the I/O that was queued at the time
* of the call to aio_fsync() that is guaranteed to be forced to the relevant
* completion state. The completion of subsequent I/O on the file descriptor is
* not guaranteed to be completed in a synchronized fashion.
*
* 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.
* If the operation does not complete successfully, the error status for the
* operation shall be set to indicate the error. The aio_sigevent member determines
* the asynchronous notification to occur as specified in Signal Generation and
* Delivery when all operations have achieved synchronized I/O completion. All
* other members of the structure referenced by aiocbp are ignored. If the control
* block referenced by aiocbp becomes an illegal address prior to asynchronous
* I/O completion, then the behavior is undefined.
*
* If the aio_fsync() function fails or aiocbp indicates an error condition,
* data is not guaranteed to have been successfully transferred.
*/
static void aio_fync_work(struct rt_work* work, void* work_data)
{
int result;
rt_base_t level;
struct aiocb *cb = (struct aiocb*)work_data;
RT_ASSERT(cb != RT_NULL);
result = fsync(cb->aio_fildes);
/* modify result */
level = rt_hw_interrupt_disable();
if (result < 0)
cb->aio_result = errno;
else
cb->aio_result = 0;
rt_hw_interrupt_enable(level);
return ;
}
/**
* @brief Initiates an asynchronous fsync operation.
*
* This function initiates an asynchronous fsync operation on the file associated
* with the specified aiocb structure. The operation is queued to the workqueue
* for execution.
*
* @param op The operation to be performed. This parameter is ignored.
* @param cb Pointer to the aiocb structure representing the asynchronous fsync operation.
*
* @return Returns 0 on success.
*/
int aio_fsync(int op, struct aiocb *cb)
{
rt_base_t level;
if (!cb) return -EINVAL;
level = rt_hw_interrupt_disable();
cb->aio_result = -EINPROGRESS;
rt_hw_interrupt_enable(level);
rt_work_init(&(cb->aio_work), aio_fync_work, cb);
rt_workqueue_dowork(aio_queue, &(cb->aio_work));
return 0;
}
/**
* @brief Worker function for asynchronous read operation.
*
* This function performs the actual reading of data from the file associated with
* the specified aiocb structure. It sets the result of the operation in the
* aio_result field of the aiocb structure.
*
* @param work Pointer to the work item.
* @param work_data Pointer to the aiocb structure representing the asynchronous read operation.
*/
static void aio_read_work(struct rt_work* work, void* work_data)
{
int len;
rt_base_t level;
uint8_t *buf_ptr;
struct aiocb *cb = (struct aiocb*)work_data;
buf_ptr = (uint8_t*)cb->aio_buf;
/* seek to offset */
lseek(cb->aio_fildes, cb->aio_offset, SEEK_SET);
len = read(cb->aio_fildes, &buf_ptr[cb->aio_offset], cb->aio_nbytes);
/* modify result */
level = rt_hw_interrupt_disable();
if (len <= 0)
cb->aio_result = errno;
else
cb->aio_result = len;
rt_hw_interrupt_enable(level);
return ;
}
/**
* The aio_read() function shall 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
* to the file or device (even when the data cannot be delivered immediately).
*
* If prioritized I/O is supported for this file, then the asynchronous operation
* shall be submitted at a priority equal to a base scheduling priority minus
* aiocbp->aio_reqprio. If Thread Execution Scheduling is not supported, then
* the base scheduling priority is that of the calling process;
*
* otherwise, the base scheduling priority is that of the calling thread.
*
* 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.
*
* The aio_sigevent member specifies the notification which occurs when the
* request is completed.
*
* The aiocbp->aio_lio_opcode field shall be ignored by aio_read().
*
* The aiocbp argument points to an aiocb structure. If the buffer pointed to by
* aiocbp->aio_buf or the control block pointed to by aiocbp becomes an illegal
* address prior to asynchronous I/O completion, then the behavior is undefined.
*
* Simultaneous asynchronous operations using the same aiocbp produce undefined
* results.
*
* If synchronized I/O is enabled on the file associated with aiocbp->aio_fildes,
* the behavior of this function shall be according to the definitions of synchronized
* I/O data integrity completion and synchronized I/O file integrity completion.
*
* For any system action that changes the process memory space while an asynchronous
* I/O is outstanding to the address range being changed, the result of that action
* is undefined.
*
* For regular files, no data transfer shall occur past the offset maximum
* established in the open file description associated with aiocbp->aio_fildes.
*
*/
int aio_read(struct aiocb *cb)
{
rt_base_t level;
if (!cb) return -EINVAL;
if (cb->aio_offset < 0) return -EINVAL;
level = rt_hw_interrupt_disable();
cb->aio_result = -EINPROGRESS;
rt_hw_interrupt_enable(level);
/* en-queue read work */
rt_work_init(&(cb->aio_work), aio_read_work, cb);
rt_workqueue_dowork(aio_queue, &(cb->aio_work));
return 0;
}
/**
* The aio_return() function shall 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 *cb)
{
if (cb)
{
if (cb->aio_result < 0)
rt_set_errno(cb->aio_result);
return cb->aio_result;
}
return -EINVAL;
}
/**
* The aio_suspend() function shall suspend the calling thread until at least
* one of the asynchronous I/O operations referenced by the list 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 list 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 list 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. If this array contains pointers
* that refer to aiocb structures that have not been used in submitting asynchronous
* I/O, the effect is undefined.
*
* If the time interval indicated in the timespec structure pointed to by timeout
* passes before any of the I/O operations referenced by list are completed, then
* aio_suspend() shall return with an error.
*/
int aio_suspend(const struct aiocb *const list[], int nent,
const struct timespec *timeout)
{
return -ENOSYS;
}
/**
* @brief Worker function for asynchronous write operation.
*
* This function performs the actual writing of data to the file associated with
* the specified aiocb structure. It sets the result of the operation in the
* aio_result field of the aiocb structure.
*
* @param work Pointer to the work item.
* @param work_data Pointer to the aiocb structure representing the asynchronous write operation.
*/
static void aio_write_work(struct rt_work* work, void* work_data)
{
rt_base_t level;
int len, oflags;
uint8_t *buf_ptr;
struct aiocb *cb = (struct aiocb*)work_data;
buf_ptr = (uint8_t*)cb->aio_buf;
/* whether seek offset */
oflags = fcntl(cb->aio_fildes, F_GETFL, 0);
if ((oflags & O_APPEND) == 0)
{
lseek(cb->aio_fildes, SEEK_SET, cb->aio_offset);
}
/* write data */
len = write(cb->aio_fildes, buf_ptr, cb->aio_nbytes);
/* modify result */
level = rt_hw_interrupt_disable();
if (len <= 0)
cb->aio_result = errno;
else
cb->aio_result = len;
rt_hw_interrupt_enable(level);
return;
}
/**
* The aio_write() function shall 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 to the file or device.
*
* 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.
*
* The aiocbp argument points to an aiocb structure. If the buffer pointed to by
* aiocbp->aio_buf or the control block pointed to by aiocbp becomes an illegal
* address prior to asynchronous I/O completion, then the behavior is undefined.
*
* If O_APPEND is not set for the file descriptor aio_fildes, then the requested
* operation shall take 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. If O_APPEND is
* set for the file descriptor, or if aio_fildes is associated with a device that
* is incapable of seeking, write operations append to the file in the same order
* as the calls were made, except under circumstances described in Asynchronous
* I/O. After a successful call to enqueue an asynchronous I/O operation, the value
* of the file offset for the file is unspecified.
*
* The aio_sigevent member specifies the notification which occurs when the request
* is completed.
*
* The aiocbp->aio_lio_opcode field shall be ignored by aio_write().
*
* Simultaneous asynchronous operations using the same aiocbp produce undefined
* results.
*
* If synchronized I/O is enabled on the file associated with aiocbp->aio_fildes,
* the behavior of this function shall be according to the definitions of synchronized
* I/O data integrity completion, and synchronized I/O file integrity completion.
*
* For regular files, no data transfer shall occur past the offset maximum established
* in the open file description associated with aiocbp->aio_fildes.
*/
int aio_write(struct aiocb *cb)
{
int oflags;
rt_base_t level;
if (!cb || (cb->aio_buf == NULL)) return -EINVAL;
/* check access mode */
oflags = fcntl(cb->aio_fildes, F_GETFL, 0);
/* If the flag is not in write only or read-write mode, it cannot be written then an invalid parameter is returned */
if ((oflags & O_ACCMODE) != O_WRONLY &&
(oflags & O_ACCMODE) != O_RDWR)
return -EINVAL;
level = rt_hw_interrupt_disable();
cb->aio_result = -EINPROGRESS;
rt_hw_interrupt_enable(level);
rt_work_init(&(cb->aio_work), aio_write_work, cb);
rt_workqueue_dowork(aio_queue, &(cb->aio_work));
return 0;
}
/**
* The lio_listio() function shall 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 declared in
* <aio.h> 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. If sig is not NULL, asynchronous notification occurs as specified
* in Signal Generation and Delivery when all the requests in list have completed.
*
* The I/O requests enumerated by list are submitted in an unspecified order.
*
* The list argument is an array of pointers to aiocb structures. The array contains
* nent elements. The array may contain NULL elements, which shall be ignored.
*
* If the buffer pointed to by list or the aiocb structures pointed to by the
* elements of the array list become illegal addresses before all asynchronous I/O
* completed and, if necessary, the notification is sent, then the behavior is
* undefined. If the buffers pointed to by the aio_buf member of the aiocb structure
* pointed to by the elements of the array list become illegal addresses prior to
* the asynchronous I/O associated with that aiocb structure being completed, the
* behavior is undefined.
*
* The aio_lio_opcode field of each aiocb structure specifies the operation to be
* performed. The supported operations are LIO_READ, LIO_WRITE, and LIO_NOP; these
* symbols are defined in <aio.h>. The LIO_NOP operation causes the list entry to
* be ignored. If the aio_lio_opcode element is equal to LIO_READ, then an I/O operation
* is submitted as if by a call to aio_read() with the aiocbp equal to the address
* of the aiocb structure. If the aio_lio_opcode element is equal to LIO_WRITE, then
* an I/O operation is submitted as if by a call to aio_write() with the aiocbp equal
* to the address of the aiocb structure.
*
* The aio_fildes member specifies the file descriptor on which the operation is to
* be performed.
*
* The aio_buf member specifies the address of the buffer to or from which the data
* is transferred.
*
* The aio_nbytes member specifies the number of bytes of data to be transferred.
*
* The members of the aiocb structure further describe the I/O operation to be
* performed, in a manner identical to that of the corresponding aiocb structure
* when used by the aio_read() and aio_write() functions.
*
* The nent argument specifies how many elements are members of the list; that is,
* the length of the array.
*
* The behavior of this function is altered according to the definitions of synchronized
* I/O data integrity completion and synchronized I/O file integrity completion if
* synchronized I/O is enabled on the file associated with aio_fildes.
*
* For regular files, no data transfer shall occur past the offset maximum established
* in the open file description associated with aiocbp->aio_fildes.
*
* If sig->sigev_notify is SIGEV_THREAD and sig->sigev_notify_attributes is a
* non-null pointer and the block pointed to by this pointer becomes an illegal
* address prior to all asynchronous I/O being completed, then the behavior is
* undefined.
*/
int lio_listio(int mode, struct aiocb * const list[], int nent,
struct sigevent *sig)
{
return -ENOSYS;
}
/**
* @brief Initializes the asynchronous I/O system.
*
* This function initializes the asynchronous I/O system by creating a workqueue
* for asynchronous I/O operations.
*
* @return Returns 0 on success.
*/
int aio_system_init(void)
{
aio_queue = rt_workqueue_create("aio", 2048, RT_THREAD_PRIORITY_MAX/2);
RT_ASSERT(aio_queue != NULL);
return 0;
}
INIT_COMPONENT_EXPORT(aio_system_init);