Adding upstream version 1.47.0.upstream/1.47.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 459 insertions, 0 deletions

diff --git a/lib/ext2fs/dosio.c b/lib/ext2fs/dosio.c
new file mode 100644
index 0000000..d0cf269
--- /dev/null
+++ b/lib/ext2fs/dosio.c
@@ -0,0 +1,459 @@
+/*
+ * dosio.c -- Disk I/O module for the ext2fs/DOS library.
+ *
+ * Copyright (c) 1997 by Theodore Ts'o.
+ *
+ * Copyright (c) 1997 Mark Habersack
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#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 = {
+	.magic		= EXT2_ET_MAGIC_IO_MANAGER,
+	.name		= "DOS I/O Manager",
+	.open		= dos_open,
+	.close		= dos_close,
+	.set_blksize	= dos_set_blksize,
+	.read_blk	= dos_read_blk,
+	.write_blk	= dos_write_blk,
+	.flush		= 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;
+    free(part->dev);
+    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;
+    free(part->dev);
+    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;
+    free(part->dev);
+    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)
+{
+	free(channel->name);
+	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;
+}