/Designs/GPSRL02A/SW/partition.h
0,0 → 1,201
 
/*
* Copyright (c) 2006-2007 by Roland Riegel <feedback@roland-riegel.de>
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of either the GNU General Public License version 2
* or the GNU Lesser General Public License version 2.1, both as
* published by the Free Software Foundation.
*/
 
#ifndef PARTITION_H
#define PARTITION_H
 
#include <stdint.h>
 
/**
* \addtogroup partition
*
* @{
*/
/**
* \file
* Partition table header (license: GPLv2 or LGPLv2.1)
*
* \author Roland Riegel
*/
 
/**
* The partition table entry is not used.
*/
#define PARTITION_TYPE_FREE 0x00
/**
* The partition contains a FAT12 filesystem.
*/
#define PARTITION_TYPE_FAT12 0x01
/**
* The partition contains a FAT16 filesystem with 32MB maximum.
*/
#define PARTITION_TYPE_FAT16_32MB 0x04
/**
* The partition is an extended partition with its own partition table.
*/
#define PARTITION_TYPE_EXTENDED 0x05
/**
* The partition contains a FAT16 filesystem.
*/
#define PARTITION_TYPE_FAT16 0x06
/**
* The partition contains a FAT32 filesystem.
*/
#define PARTITION_TYPE_FAT32 0x0b
/**
* The partition contains a FAT32 filesystem with LBA.
*/
#define PARTITION_TYPE_FAT32_LBA 0x0c
/**
* The partition contains a FAT16 filesystem with LBA.
*/
#define PARTITION_TYPE_FAT16_LBA 0x0e
/**
* The partition is an extended partition with LBA.
*/
#define PARTITION_TYPE_EXTENDED_LBA 0x0f
/**
* The partition has an unknown type.
*/
#define PARTITION_TYPE_UNKNOWN 0xff
 
/**
* A function pointer used to read from the partition.
*
* \param[in] offset The offset on the device where to start reading.
* \param[out] buffer The buffer into which to place the data.
* \param[in] length The count of bytes to read.
*/
typedef uint8_t (*device_read_t)(uint32_t offset, uint8_t* buffer, uint16_t length);
/**
* A function pointer passed to a \c device_read_interval_t.
*
* \param[in] buffer The buffer which contains the data just read.
* \param[in] offset The offset from which the data in \c buffer was read.
* \param[in] p An opaque pointer.
* \see device_read_interval_t
*/
typedef uint8_t (*device_read_callback_t)(uint8_t* buffer, uint32_t offset, void* p);
/**
* A function pointer used to continuously read units of \c interval bytes
* and call a callback function.
*
* This function starts reading at the specified offset. Every \c interval bytes,
* it calls the callback function with the associated data buffer.
*
* By returning zero, the callback may stop reading.
*
* \param[in] offset Offset from which to start reading.
* \param[in] buffer Pointer to a buffer which is at least interval bytes in size.
* \param[in] interval Number of bytes to read before calling the callback function.
* \param[in] length Number of bytes to read altogether.
* \param[in] callback The function to call every interval bytes.
* \param[in] p An opaque pointer directly passed to the callback function.
* \returns 0 on failure, 1 on success
* \see device_read_t
*/
typedef uint8_t (*device_read_interval_t)(uint32_t offset, uint8_t* buffer, uint16_t interval, uint16_t length, device_read_callback_t callback, void* p);
/**
* A function pointer used to write to the partition.
*
* \param[in] offset The offset on the device where to start writing.
* \param[in] buffer The buffer which to write.
* \param[in] length The count of bytes to write.
*/
typedef uint8_t (*device_write_t)(uint32_t offset, const uint8_t* buffer, uint16_t length);
/**
* A function pointer passed to a \c device_write_interval_t.
*
* \param[in] buffer The buffer which receives the data to write.
* \param[in] offset The offset to which the data in \c buffer will be written.
* \param[in] p An opaque pointer.
* \returns The number of bytes put into \c buffer
* \see device_write_interval_t
*/
typedef uint16_t (*device_write_callback_t)(uint8_t* buffer, uint32_t offset, void* p);
/**
* A function pointer used to continuously write a data stream obtained from
* a callback function.
*
* This function starts writing at the specified offset. To obtain the
* next bytes to write, it calls the callback function. The callback fills the
* provided data buffer and returns the number of bytes it has put into the buffer.
*
* By returning zero, the callback may stop writing.
*
* \param[in] offset Offset where to start writing.
* \param[in] buffer Pointer to a buffer which is used for the callback function.
* \param[in] length Number of bytes to write in total. May be zero for endless writes.
* \param[in] callback The function used to obtain the bytes to write.
* \param[in] p An opaque pointer directly passed to the callback function.
* \returns 0 on failure, 1 on success
* \see device_write_t
*/
typedef uint8_t (*device_write_interval_t)(uint32_t offset, uint8_t* buffer, uint16_t length, device_write_callback_t callback, void* p);
 
/**
* Describes a partition.
*/
struct partition_struct
{
/**
* The function which reads data from the partition.
*
* \note The offset given to this function is relative to the whole disk,
* not to the start of the partition.
*/
device_read_t device_read;
/**
* The function which repeatedly reads a constant amount of data from the partition.
*
* \note The offset given to this function is relative to the whole disk,
* not to the start of the partition.
*/
device_read_interval_t device_read_interval;
/**
* The function which writes data to the partition.
*
* \note The offset given to this function is relative to the whole disk,
* not to the start of the partition.
*/
device_write_t device_write;
/**
* The function which repeatedly writes data to the partition.
*
* \note The offset given to this function is relative to the whole disk,
* not to the start of the partition.
*/
device_write_interval_t device_write_interval;
 
/**
* The type of the partition.
*
* Compare this value to the PARTITION_TYPE_* constants.
*/
uint8_t type;
/**
* The offset in bytes on the disk where this partition starts.
*/
uint32_t offset;
/**
* The length in bytes of this partition.
*/
uint32_t length;
};
 
struct partition_struct* partition_open(device_read_t device_read, device_read_interval_t device_read_interval, device_write_t device_write, device_write_interval_t device_write_interval, int8_t index);
uint8_t partition_close(struct partition_struct* partition);
 
/**
* @}
*/
 
#endif