31 lines
598 B
C
31 lines
598 B
C
#ident "$Revision: 1.4 $"
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/*
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* Map a byte offset in an inode to a disk block number.
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*/
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#include "efs.h"
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efs_daddr_t
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efs_bmap(struct efs_dinode *di, off_t offset, off_t count)
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{
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off_t fileoff;
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extent *ex;
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/* insure that file is big enough, first */
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if (offset + count > di->di_size)
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efs_extend(di, offset + count - di->di_size);
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offset = BTOBBT(offset);
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fileoff = 0;
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ex = &di->di_u.di_extents[0];
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while (fileoff + ex->ex_length <= offset) {
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fileoff += ex->ex_length;
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ex++;
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}
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/*
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* Block lies within this extent. Return where.
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*/
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return (ex->ex_bn + offset - fileoff);
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}
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