diff options
| -rw-r--r-- | winsup/cygwin/ChangeLog | 7 | ||||
| -rw-r--r-- | winsup/cygwin/fhandler_floppy.cc | 131 |
2 files changed, 91 insertions, 47 deletions
diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog index 47ed0a0..d404037 100644 --- a/winsup/cygwin/ChangeLog +++ b/winsup/cygwin/ChangeLog @@ -1,3 +1,10 @@ +2001-02-28 Egor Duda <deo@logos-m.ru> + + * fhandler_floppy.cc (fhandler_dev_floppy::lseek): Determine + drive geometry or partition size to allow seeking from the end of + raw floppy device. Don't allow positioning past the end of media or + to offsets bigger then max off_t. + 2001-02-27 Egor Duda <deo@logos-m.ru> * fhandler.h (class fhandler_console): Make all variables that diff --git a/winsup/cygwin/fhandler_floppy.cc b/winsup/cygwin/fhandler_floppy.cc index a767443..bab0b0a 100644 --- a/winsup/cygwin/fhandler_floppy.cc +++ b/winsup/cygwin/fhandler_floppy.cc @@ -16,6 +16,7 @@ details. */ #include <unistd.h> #include "fhandler.h" #include "cygerrno.h" +#include <winioctl.h> /**********************************************************************/ /* fhandler_dev_floppy */ @@ -80,78 +81,114 @@ off_t fhandler_dev_floppy::lseek (off_t offset, int whence) { int ret; - DWORD off; char buf[512]; - - if (whence == SEEK_SET) + long long drive_size = 0; + long long lloffset = offset; + long long current_position; + off_t sector_aligned_offset; + off_t bytes_left; + DWORD low; + LONG high = 0; + + if (os_being_run == winNT) { - if (offset < 0) + DISK_GEOMETRY di; + PARTITION_INFORMATION pi; + DWORD bytes_read; + + if ( !DeviceIoControl ( get_handle(), + IOCTL_DISK_GET_DRIVE_GEOMETRY, + NULL, 0, + &di, sizeof (di), + &bytes_read, NULL) ) { - set_errno (EINVAL); - return -1; - } - - /* Invalidate buffer. */ - ret = writebuf (); - if (ret) - return ret; - devbufstart = devbufend = 0; - - off = (offset / 512) * 512; - - if (SetFilePointer (get_handle (), off, NULL, FILE_BEGIN) - == INVALID_SET_FILE_POINTER) + __seterrno (); + return -1; + } + debug_printf ( "disk geometry: (%ld cyl)*(%ld trk)*(%ld sec)*(%ld bps)", + di.Cylinders.LowPart, + di.TracksPerCylinder, + di.SectorsPerTrack, + di.BytesPerSector ); + if ( DeviceIoControl ( get_handle (), + IOCTL_DISK_GET_PARTITION_INFO, + NULL, 0, + &pi, sizeof (pi), + &bytes_read, NULL )) { - __seterrno (); - return -1; - } - return raw_read (buf, offset - off); + debug_printf ( "partition info: %ld (%ld)", + pi.StartingOffset.LowPart, + pi.PartitionLength.LowPart); + drive_size = (long long) pi.PartitionLength.QuadPart; + } + else + { + drive_size = (long long) di.Cylinders.QuadPart * di.TracksPerCylinder * + di.SectorsPerTrack * di.BytesPerSector; + } + debug_printf ( "drive size: %ld", drive_size ); } - else if (whence == SEEK_CUR) + + if (whence == SEEK_END && drive_size > 0) { - DWORD low; - LONG high = 0; + lloffset = offset + drive_size; + whence = SEEK_SET; + } + if (whence == SEEK_CUR) + { low = SetFilePointer (get_handle (), 0, &high, FILE_CURRENT); if (low == INVALID_SET_FILE_POINTER && GetLastError ()) { __seterrno (); return -1; } - long long cur = (long long) high << 32 + low; + current_position = (long long) low + ((long long) high << 32); if (is_writing) - cur += devbufend - devbufstart; + current_position += devbufend - devbufstart; else - cur -= devbufend - devbufstart; - + current_position -= devbufend - devbufstart; + + lloffset += current_position; + whence = SEEK_SET; + } + + if (lloffset < 0 || + drive_size > 0 && lloffset > drive_size) + { + set_errno (EINVAL); + return -1; + } + high = lloffset >> 32; + low = lloffset & 0xffffffff; + if ( high || (off_t) low < 0 ) + { + set_errno (EFBIG); + return -1; + } + offset = (off_t) low; + + /* FIXME: sector can possibly be not 512 bytes long */ + sector_aligned_offset = (offset / 512) * 512; + bytes_left = offset - sector_aligned_offset; + + if (whence == SEEK_SET) + { /* Invalidate buffer. */ ret = writebuf (); if (ret) return ret; devbufstart = devbufend = 0; - cur += offset; - if (cur < 0) - { - set_errno (EINVAL); - return -1; - } - - long long set = (cur / 512) * 512; - high = set >> 32; - low = set & 0xffffffff; - - off = cur - set; - - low = SetFilePointer (get_handle (), low, &high, FILE_BEGIN); - if (low == INVALID_SET_FILE_POINTER && GetLastError ()) - { + if (SetFilePointer (get_handle (), sector_aligned_offset, NULL, FILE_BEGIN) + == INVALID_SET_FILE_POINTER) + { __seterrno (); return -1; } - return raw_read (buf, off); + return sector_aligned_offset + raw_read (buf, bytes_left); } - /* SEEK_END is not supported on raw disk devices. */ + set_errno (EINVAL); return -1; } |