kfile.h File Reference

Virtual KFile I/O interface. More...

#include <cfg/compiler.h>
#include <cfg/debug.h>
#include <cfg/macros.h>

Go to the source code of this file.


Data Structures

struct  KFile
 Context data for callback functions which operate on pseudo files. More...

Typedefs

typedef int32_t kfile_off_t
 KFile offset type, used by kfile_seek function.
typedef size_t(* ReadFunc_t )(struct KFile *fd, void *buf, size_t size)
 Prototypes for KFile access functions.
typedef size_t(* WriteFunc_t )(struct KFile *fd, const void *buf, size_t size)
 Write to file.
typedef kfile_off_t(* SeekFunc_t )(struct KFile *fd, kfile_off_t offset, KSeekMode whence)
 Seek into file (if seekable).
typedef struct KFile *(* ReOpenFunc_t )(struct KFile *fd)
 Close and reopen file fd.
typedef int(* CloseFunc_t )(struct KFile *fd)
 Close file.
typedef int(* FlushFunc_t )(struct KFile *fd)
 Flush file I/O.
typedef int(* ErrorFunc_t )(struct KFile *fd)
 Get file error mask.
typedef void(* ClearErrFunc_t )(struct KFile *fd)
 Clear errors.

Enumerations

enum  KSeekMode { KSM_SEEK_SET, KSM_SEEK_CUR, KSM_SEEK_END }
 Costants for repositioning read/write file offset. More...

Functions

kfile_off_t kfile_genericSeek (struct KFile *fd, kfile_off_t offset, KSeekMode whence)
 Generic implementation of kfile_seek.
struct KFile * kfile_genericReopen (struct KFile *fd)
 Generic implementation of kfile_reopen.
int kfile_putc (int c, struct KFile *fd)
 Generic putc implementation using kfile_write.
int kfile_getc (struct KFile *fd)
 Generic getc implementation using kfile_read.
int kfile_print (struct KFile *fd, const char *s)
 Write a string to kfile fd.
bool kfile_test (KFile *fd, uint8_t *test_buf, uint8_t *save_buf, size_t size)
 Kfile test function.
size_t kfile_read (struct KFile *fd, void *buf, size_t size)
 Interface functions for KFile access.

Detailed Description

Virtual KFile I/O interface.

KFile is a generic interface for file I/O. It uses an object-oriented model to supply a generic interface for drivers to communicate. This module contains only definitions, the instance structure and an API. Each KFile user should implement at least some methods. E.G. If you have a serial driver and want to comply to KFile interface, you have to declare your context structure:

 typedef struct KFileSerial
 {
    KFile fd;
    Serial *ser;
 } KFileSerial;

You should also supply a macro for casting KFile to KFileSerial:

 INLINE KFileSerial * KFILESERIAL(KFile *fd)
 {
    ASSERT(fd->_type == KFT_SERIAL);
    return (KFileSerial *)fd;
 }

Then you can implement as much interface functions as you like and leave the others to NULL. ser_close implementation example:

 static int ser_kfile_close(struct KFile *fd)
 {
    KFileSerial *fds = KFILESERIAL(fd);
    ser_close(fds->ser);
    return 0;
 }
KFILESERIAL macro helps to ensure that obj passed is really a Serial.

KFile interface do not supply the open function: this is deliberate, because in embedded systems each device has its own init parameters. For the same reason specific file settings (like baudrate for Serial, for example) are demanded to specific driver implementation.

Version:
Id
kfile.h 1144 2008-02-19 16:56:14Z batt
Author:
Bernardo Innocenti <bernie@develer.com>

Francesco Sacchi <batt@develer.com>

Daniele Basile <asterix@develer.com>

Definition in file kfile.h.

Typedef Documentation

typedef int(* CloseFunc_t)(struct KFile *fd)

Close file.

Returns:
0 on success, EOF on errors.

Definition at line 148 of file kfile.h.

typedef int(* ErrorFunc_t)(struct KFile *fd)

Get file error mask.

Returns:
0 on success or file error code, device specific.

Definition at line 160 of file kfile.h.

typedef int(* FlushFunc_t)(struct KFile *fd)

Flush file I/O.

Returns:
0 on success, EOF on errors.

Definition at line 154 of file kfile.h.

typedef size_t(* ReadFunc_t)(struct KFile *fd, void *buf, size_t size)

Prototypes for KFile access functions.

I/O file functions must be ANSI compliant.

Note:
A KFile user can choose which function subset to implement, but has to set to NULL unimplemented features. Read from file.
Returns:
the number of bytes read.

Definition at line 124 of file kfile.h.

typedef struct KFile*(* ReOpenFunc_t)(struct KFile *fd)

Close and reopen file fd.

The reopening is done with the former file parameters and access modes.

Definition at line 142 of file kfile.h.

typedef kfile_off_t(* SeekFunc_t)(struct KFile *fd, kfile_off_t offset, KSeekMode whence)

Seek into file (if seekable).

Returns:
the new file offset or EOF on errors.

Definition at line 136 of file kfile.h.

typedef size_t(* WriteFunc_t)(struct KFile *fd, const void *buf, size_t size)

Write to file.

Returns:
the number of bytes written.

Definition at line 130 of file kfile.h.

Enumeration Type Documentation

enum KSeekMode

Costants for repositioning read/write file offset.

These are needed because on some embedded platforms ANSI I/O library may not be present.

Enumerator:
KSM_SEEK_SET  Seek from file beginning.
KSM_SEEK_CUR  Seek from file current position.
KSM_SEEK_END  Seek from file end.

Definition at line 105 of file kfile.h.

Function Documentation

struct KFile* kfile_genericReopen ( struct KFile *  fd  )  [read]

Generic implementation of kfile_reopen.

Generic implementation of kfile_reopen.

This is a generic implementation that only flush file and reset seek_pos to 0.

Definition at line 214 of file kfile.c.

kfile_off_t kfile_genericSeek ( struct KFile *  fd,
kfile_off_t  offset,
KSeekMode  whence 
)

Generic implementation of kfile_seek.

Generic implementation of kfile_seek.

This is a generic implementation of seek function, you can redefine it in your local module if needed.

Definition at line 175 of file kfile.c.

int kfile_print ( struct KFile *  fd,
const char *  s 
)

Write a string to kfile fd.

Returns:
0 if OK, EOF in case of error.

Definition at line 108 of file kfile.c.

size_t kfile_read ( struct KFile *  fd,
void *  buf,
size_t  size 
) [inline]

Interface functions for KFile access.

Note:
Remember to change following functions if KFile interface changes.

Definition at line 212 of file kfile.h.