97 lines
2.3 KiB
C
97 lines
2.3 KiB
C
/* Copyright 1999-2003,2006,2008,2009 Alain Knaff.
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* This file is part of mtools.
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*
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* Mtools is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* Mtools is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with Mtools. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "sysincludes.h"
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#include "stream.h"
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#include "fsP.h"
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#include "llong.h"
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#include "mtools.h"
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#if 1
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const mt_off_t max_off_t_31 = MAX_OFF_T_B(31); /* Floppyd */
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static const mt_off_t max_off_t_32 = MAX_OFF_T_B(32); /* Directory */
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const mt_off_t max_off_t_41 = MAX_OFF_T_B(41); /* SCSI */
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const mt_off_t max_off_t_seek = MAX_OFF_T_B(SEEK_BITS); /* SCSI */
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#else
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const mt_off_t max_off_t_31 = MAX_OFF_T_B(10); /* Floppyd */
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const mt_off_t max_off_t_41 = MAX_OFF_T_B(10); /* SCSI */
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const mt_off_t max_off_t_seek = MAX_OFF_T_B(10); /* SCSI */
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#endif
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int fileTooBig(mt_off_t off) {
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return (off & ~max_off_t_32) != 0;
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}
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off_t truncBytes32(mt_off_t off)
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{
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if (fileTooBig(off)) {
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fprintf(stderr, "Internal error, offset too big\n");
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exit(1);
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}
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return (off_t) off;
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}
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mt_off_t sectorsToBytes(Stream_t *Stream, off_t off)
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{
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DeclareThis(Fs_t);
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return (mt_off_t) off << This->sectorShift;
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}
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#if defined HAVE_LLSEEK
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# ifndef HAVE_LLSEEK_PROTOTYPE
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extern long long llseek (int fd, long long offset, int origin);
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# endif
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#endif
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#if defined HAVE_LSEEK64
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# ifndef HAVE_LSEEK64_PROTOTYPE
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extern long long lseek64 (int fd, long long offset, int origin);
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# endif
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#endif
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int mt_lseek(int fd, mt_off_t where, int whence)
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{
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#if defined HAVE_LSEEK64
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if(lseek64(fd, where, whence) >= 0)
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return 0;
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else
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return -1;
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#elif defined HAVE_LLSEEK
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if(llseek(fd, where, whence) >= 0)
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return 0;
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else
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return -1;
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#else
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if (lseek(fd, (off_t) where, whence) >= 0)
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return 0;
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else
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return 1;
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#endif
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}
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unsigned int log_2(int size)
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{
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unsigned int i;
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for(i=0; i<24; i++) {
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if(1 << i == size)
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return i;
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}
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return 24;
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}
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