+++ /dev/null
-/*
- * dosio.c -- Disk I/O module for the ext2fs/DOS library.
- *
- * Copyright (c) 1997 by Theodore Ts'o.
- *
- * Copyright (c) 1997 Mark Habersack
- * This file may be distributed under the terms of the GNU Public License.
- *
- */
-
-#include <stdio.h>
-#include <bios.h>
-#include <string.h>
-#include <ctype.h>
-#include <io.h>
-#ifdef HAVE_ERRNO_H
-#include <errno.h>
-#endif
-
-#include <ext2fs/ext2_types.h>
-#include "utils.h"
-#include "dosio.h"
-#include "et/com_err.h"
-#include "ext2_err.h"
-#include "ext2fs/io.h"
-
-/*
- * Some helper macros
- */
-#define LINUX_EXT2FS 0x83
-#define LINUX_SWAP 0x82
-#define WRITE_ERR(_msg_) write(2, _msg_, strlen(_msg_))
-#define WRITE_ERR_S(_msg_) write(2, _msg_, sizeof(_msg_))
-
-/*
- * Exported variables
- */
-unsigned long _dio_error;
-unsigned long _dio_hw_error;
-
-/*
- * Array of all opened partitions
- */
-static PARTITION **partitions = NULL;
-static unsigned short npart = 0; /* Number of mapped partitions */
-static PARTITION *active = NULL;
-
-/*
- * I/O Manager routine prototypes
- */
-static errcode_t dos_open(const char *dev, int flags, io_channel *channel);
-static errcode_t dos_close(io_channel channel);
-static errcode_t dos_set_blksize(io_channel channel, int blksize);
-static errcode_t dos_read_blk(io_channel channel, unsigned long block,
- int count, void *buf);
-static errcode_t dos_write_blk(io_channel channel, unsigned long block,
- int count, const void *buf);
-static errcode_t dos_flush(io_channel channel);
-
-static struct struct_io_manager struct_dos_manager = {
- EXT2_ET_MAGIC_IO_MANAGER,
- "DOS I/O Manager",
- dos_open,
- dos_close,
- dos_set_blksize,
- dos_read_blk,
- dos_write_blk,
- dos_flush
-};
-io_manager dos_io_manager = &struct_dos_manager;
-
-/*
- * Macro taken from unix_io.c
- */
-/*
- * For checking structure magic numbers...
- */
-
-#define EXT2_CHECK_MAGIC(struct, code) \
- if ((struct)->magic != (code)) return (code)
-
-/*
- * Calculates a CHS address of a sector from its LBA
- * offset for the given partition.
- */
-static void lba2chs(unsigned long lba_addr, CHS *chs, PARTITION *part)
-{
- unsigned long abss;
-
- chs->offset = lba_addr & 0x000001FF;
- abss = (lba_addr >> 9) + part->start;
- chs->cyl = abss / (part->sects * part->heads);
- chs->head = (abss / part->sects) % part->heads;
- chs->sector = (abss % part->sects) + 1;
-}
-
-#ifdef __TURBOC__
-#pragma argsused
-#endif
-/*
- * Scans the passed partition table looking for *pno partition
- * that has LINUX_EXT2FS type.
- *
- * TODO:
- * For partition numbers >5 Linux uses DOS extended partitions -
- * dive into them an return an appropriate entry. Also dive into
- * extended partitions when scanning for a first Linux/ext2fs.
- */
-static PTABLE_ENTRY *scan_partition_table(PTABLE_ENTRY *pentry,
- unsigned short phys,
- unsigned char *pno)
-{
- unsigned i;
-
- if(*pno != 0xFF && *pno >= 5)
- return NULL; /* We don't support extended partitions for now */
-
- if(*pno != 0xFF)
- {
- if(pentry[*pno].type == LINUX_EXT2FS)
- return &pentry[*pno];
- else
- {
- if(!pentry[*pno].type)
- *pno = 0xFE;
- else if(pentry[*pno].type == LINUX_SWAP)
- *pno = 0xFD;
- return NULL;
- }
- }
-
- for(i = 0; i < 4; i++)
- if(pentry[i].type == LINUX_EXT2FS)
- {
- *pno = i;
- return &pentry[i];
- }
-
- return NULL;
-}
-
-/*
- * Allocate libext2fs structures associated with I/O manager
- */
-static io_channel alloc_io_channel(PARTITION *part)
-{
- io_channel ioch;
-
- ioch = (io_channel)malloc(sizeof(struct struct_io_channel));
- if (!ioch)
- return NULL;
- memset(ioch, 0, sizeof(struct struct_io_channel));
- ioch->magic = EXT2_ET_MAGIC_IO_CHANNEL;
- ioch->manager = dos_io_manager;
- ioch->name = (char *)malloc(strlen(part->dev)+1);
- if (!ioch->name) {
- free(ioch);
- return NULL;
- }
- strcpy(ioch->name, part->dev);
- ioch->private_data = part;
- ioch->block_size = 1024; /* The smallest ext2fs block size */
- ioch->read_error = 0;
- ioch->write_error = 0;
-
- return ioch;
-}
-
-#ifdef __TURBOC__
-#pragma argsused
-#endif
-/*
- * Open the 'name' partition, initialize all information structures
- * we need to keep and create libext2fs I/O manager.
- */
-static errcode_t dos_open(const char *dev, int flags, io_channel *channel)
-{
- unsigned char *tmp, sec[512];
- PARTITION *part;
- PTABLE_ENTRY *pent;
- PARTITION **newparts;
-
- if(!dev)
- {
- _dio_error = ERR_BADDEV;
- return EXT2_ET_BAD_DEVICE_NAME;
- }
-
- /*
- * First check whether the dev name is OK
- */
- tmp = (unsigned char*)strrchr(dev, '/');
- if(!tmp)
- {
- _dio_error = ERR_BADDEV;
- return EXT2_ET_BAD_DEVICE_NAME;
- }
- *tmp = 0;
- if(strcmp(dev, "/dev"))
- {
- _dio_error = ERR_BADDEV;
- return EXT2_ET_BAD_DEVICE_NAME;
- }
- *tmp++ = '/';
-
- /*
- * Check whether the partition data is already in cache
- */
-
- part = (PARTITION*)malloc(sizeof(PARTITION));
- if (!part)
- return ENOMEM;
- {
- int i = 0;
-
- for(;i < npart; i++)
- if(!strcmp(partitions[i]->dev, dev))
- {
- /* Found it! Make it the active one */
- active = partitions[i];
- *channel = alloc_io_channel(active);
- if (!*channel)
- return ENOMEM;
- return 0;
- }
- }
-
- /*
- * Drive number & optionally partn number
- */
- switch(tmp[0])
- {
- case 'h':
- case 's':
- part->phys = 0x80;
- part->phys += toupper(tmp[2]) - 'A';
- /*
- * Do we have the partition number?
- */
- if(tmp[3])
- part->pno = isdigit((int)tmp[3]) ? tmp[3] - '0' - 1: 0;
- else
- part->pno = 0xFF;
- break;
-
- case 'f':
- if(tmp[2])
- part->phys = isdigit((int)tmp[2]) ? tmp[2] - '0' : 0;
- else
- part->phys = 0x00; /* We'll assume /dev/fd0 */
- break;
-
- default:
- _dio_error = ERR_BADDEV;
- return ENODEV;
- }
-
- if(part->phys < 0x80)
- {
- /* We don't support floppies for now */
- _dio_error = ERR_NOTSUPP;
- return EINVAL;
- }
-
- part->dev = strdup(dev);
-
- /*
- * Get drive's geometry
- */
- _dio_hw_error = biosdisk(DISK_GET_GEOMETRY,
- part->phys,
- 0, /* head */
- 0, /* cylinder */
- 1, /* sector */
- 1, /* just one sector */
- sec);
-
- if(!HW_OK())
- {
- _dio_error = ERR_HARDWARE;
- if (part)
- free(part);
- return EFAULT;
- }
-
- /*
- * Calculate the geometry
- */
- part->cyls = (unsigned short)(((sec[0] >> 6) << 8) + sec[1] + 1);
- part->heads = sec[3] + 1;
- part->sects = sec[0] & 0x3F;
-
- /*
- * Now that we know all we need, let's look for the partition
- */
- _dio_hw_error = biosdisk(DISK_READ, part->phys, 0, 0, 1, 1, sec);
-
- if(!HW_OK())
- {
- _dio_error = ERR_HARDWARE;
- if (part)
- free(part);
- return EFAULT;
- }
-
- pent = (PTABLE_ENTRY*)&sec[0x1BE];
- pent = scan_partition_table(pent, part->phys, &part->pno);
-
- if(!pent)
- {
- _dio_error = part->pno == 0xFE ? ERR_EMPTYPART :
- part->pno == 0xFD ? ERR_LINUXSWAP : ERR_NOTEXT2FS;
- if (part)
- free(part);
- return ENODEV;
- }
-
- /*
- * Calculate the remaining figures
- */
- {
- unsigned long fsec, fhead, fcyl;
-
- fsec = (unsigned long)(pent->start_sec & 0x3F);
- fhead = (unsigned long)pent->start_head;
- fcyl = ((pent->start_sec >> 6) << 8) + pent->start_cyl;
- part->start = fsec + fhead * part->sects + fcyl *
- (part->heads * part->sects) - 1;
- part->len = pent->size;
- }
-
- /*
- * Add the partition to the table
- */
- newparts = (PARTITION**)realloc(partitions, sizeof(PARTITION) * npart);
- if (!newparts) {
- free(part);
- return ENOMEM;
- }
- partitions = newparts;
- partitions[npart++] = active = part;
-
- /*
- * Now alloc all libe2fs structures
- */
- *channel = alloc_io_channel(active);
- if (!*channel)
- return ENOMEM;
-
- return 0;
-}
-
-static errcode_t dos_close(io_channel channel)
-{
- if (channel->name)
- free(channel->name);
- if (channel)
- free(channel);
-
- return 0;
-}
-
-static errcode_t dos_set_blksize(io_channel channel, int blksize)
-{
- channel->block_size = blksize;
-
- return 0;
-}
-
-static errcode_t dos_read_blk(io_channel channel, unsigned long block,
- int count, void *buf)
-{
- PARTITION *part;
- size_t size;
- ext2_loff_t loc;
- CHS chs;
-
- EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
- part = (PARTITION*)channel->private_data;
-
- size = (size_t)((count < 0) ? -count : count * channel->block_size);
- loc = (ext2_loff_t) block * channel->block_size;
-
- lba2chs(loc, &chs, part);
- /*
- * Potential bug here:
- * If DJGPP is used then reads of >18 sectors will fail!
- * Have to rewrite biosdisk.
- */
- _dio_hw_error = biosdisk(DISK_READ,
- part->phys,
- chs.head,
- chs.cyl,
- chs.sector,
- size < 512 ? 1 : size/512,
- buf);
-
- if(!HW_OK())
- {
- _dio_error = ERR_HARDWARE;
- return EFAULT;
- }
-
- return 0;
-}
-
-static errcode_t dos_write_blk(io_channel channel, unsigned long block,
- int count, const void *buf)
-{
- PARTITION *part;
- size_t size;
- ext2_loff_t loc;
- CHS chs;
-
- EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
- part = (PARTITION*)channel->private_data;
-
- if(count == 1)
- size = (size_t)channel->block_size;
- else
- {
- if (count < 0)
- size = (size_t)-count;
- else
- size = (size_t)(count * channel->block_size);
- }
-
- loc = (ext2_loff_t)block * channel->block_size;
- lba2chs(loc, &chs, part);
- _dio_hw_error = biosdisk(DISK_WRITE,
- part->phys,
- chs.head,
- chs.cyl,
- chs.sector,
- size < 512 ? 1 : size/512,
- (void*)buf);
-
- if(!HW_OK())
- {
- _dio_error = ERR_HARDWARE;
- return EFAULT;
- }
-
- return 0;
-}
-
-#ifdef __TURBOC__
-#pragma argsused
-#endif
-static errcode_t dos_flush(io_channel channel)
-{
- /*
- * No buffers, no flush...
- */
- return 0;
-}
+++ /dev/null
-/*
- * v1.0
- *
- * Disk I/O include file for the ext2fs/DOS library.
- *
- * Copyright (c) 1997 Mark Habersack
- * This file may be distributed under the terms of the GNU Public License.
- *
- */
-#ifndef __diskio_h
-#define __diskio_h
-#ifdef __TURBOC__
-#ifndef __LARGE__
-# error "ext2fs/DOS library requires LARGE model!"
-#endif
-#endif
-
-#ifdef __TURBOC__
-#include "msdos.h"
-#endif
-
-/*
- * A helper structure used in LBA => CHS conversion
- */
-typedef struct
-{
- unsigned short cyl; /* Cylinder (or track) */
- unsigned short head;
- unsigned short sector;
- unsigned short offset; /* Offset of byte within the sector */
-} CHS;
-
-/*
- * All partition data we need is here
- */
-typedef struct
-{
- char *dev; /* _Linux_ device name (like "/dev/hda1") */
- unsigned char phys; /* Physical DOS drive number */
- unsigned long start; /* LBA address of partition start */
- unsigned long len; /* length of partition in sectors */
- unsigned char pno; /* Partition number (read from *dev) */
-
- /* This partition's drive geometry */
- unsigned short cyls;
- unsigned short heads;
- unsigned short sects;
-} PARTITION;
-
-/*
- * PC partition table entry format
- */
-#ifdef __DJGPP__
-#pragma pack(1)
-#endif
-typedef struct
-{
- unsigned char active;
- unsigned char start_head;
- unsigned char start_sec;
- unsigned char start_cyl;
- unsigned char type;
- unsigned char end_head;
- unsigned char end_sec;
- unsigned char end_cyl;
- unsigned long first_sec_rel;
- unsigned long size;
-} PTABLE_ENTRY;
-#ifdef __DJGPP__
-#pragma pack()
-#endif
-
-/*
- * INT 0x13 operation codes
- */
-#define DISK_READ 0x02
-#define DISK_WRITE 0x03
-#define DISK_GET_GEOMETRY 0x08
-#define DISK_READY 0x10
-
-/*
- * Errors to put in _dio_error
- */
-#define ERR_BADDEV 0x00000001L
-#define ERR_HARDWARE 0x00000002L
-#define ERR_NOTSUPP 0x00000003L
-#define ERR_NOTEXT2FS 0x00000004L
-#define ERR_EMPTYPART 0x00000005L
-#define ERR_LINUXSWAP 0x00000006L
-
-/*
- * Functions in diskio.c
- */
-
-/*
- * Variable contains last module's error
- */
-extern unsigned long _dio_error;
-
-/*
- * This one contains last hardware error (if _dio_error == ERR_HARDWARE)
- */
-extern unsigned long _dio_hw_error;
-
-/*
- * Macros to check for disk hardware errors
- */
-#define HW_OK() ((unsigned char)_dio_hw_error == 0x00)
-#define HW_BAD_CMD() ((unsigned char)_dio_hw_error == 0x01)
-#define HW_NO_ADDR_MARK() ((unsigned char)_dio_hw_error == 0x02)
-#define HW_WRITE_PROT() ((unsigned char)_dio_hw_error == 0x03)
-#define HW_NO_SECTOR() ((unsigned char)_dio_hw_error == 0x04)
-#define HW_RESET_FAIL() ((unsigned char)_dio_hw_error == 0x05)
-#define HW_DISK_CHANGED() ((unsigned char)_dio_hw_error == 0x06)
-#define HW_DRIVE_FAIL() ((unsigned char)_dio_hw_error == 0x07)
-#define HW_DMA_OVERRUN() ((unsigned char)_dio_hw_error == 0x08)
-#define HW_DMA_BOUNDARY() ((unsigned char)_dio_hw_error == 0x09)
-#define HW_BAD_SECTOR() ((unsigned char)_dio_hw_error == 0x0A)
-#define HW_BAD_TRACK() ((unsigned char)_dio_hw_error == 0x0B)
-#define HW_UNSUPP_TRACK() ((unsigned char)_dio_hw_error == 0x0C)
-#define HW_BAD_CRC_ECC() ((unsigned char)_dio_hw_error == 0x10)
-#define HW_CRC_ECC_CORR() ((unsigned char)_dio_hw_error == 0x11)
-#define HW_CONTR_FAIL() ((unsigned char)_dio_hw_error == 0x20)
-#define HW_SEEK_FAIL() ((unsigned char)_dio_hw_error == 0x40)
-#define HW_ATTACH_FAIL() ((unsigned char)_dio_hw_error == 0x80)
-#define HW_DRIVE_NREADY() ((unsigned char)_dio_hw_error == 0xAA)
-#define HW_UNDEF_ERROR() ((unsigned char)_dio_hw_error == 0xBB)
-#define HW_WRITE_FAULT() ((unsigned char)_dio_hw_error == 0xCC)
-#define HW_STATUS_ERROR() ((unsigned char)_dio_hw_error == 0xE0)
-#define HW_SENSE_FAIL() ((unsigned char)_dio_hw_error == 0xFF)
-
-
-/*
- * Open the specified partition.
- * String 'dev' must have a format:
- *
- * /dev/{sd|hd|fd}[X]
- *
- * where,
- *
- * only one of the option in curly braces can be used and X is an optional
- * partition number for the given device. If X is not specified, function
- * scans the drive's partition table in search for the first Linux ext2fs
- * partition (signature 0x83). Along the way it dives into every extended
- * partition encountered.
- * Scan ends if either (a) there are no more used partition entries, or
- * (b) there is no Xth partition.
- *
- * Routine returns 0 on success and !=0 otherwise.
- */
-int open_partition(char *dev);
-
-#endif /* __diskio_h */
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