48 lines
916 B
C
48 lines
916 B
C
/*
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* This file is part of the UCB release of Plan 9. It is subject to the license
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* terms in the LICENSE file found in the top-level directory of this
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* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
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* part of the UCB release of Plan 9, including this file, may be copied,
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* modified, propagated, or distributed except according to the terms contained
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* in the LICENSE file.
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*/
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#include <u.h>
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#include <libc.h>
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#include "iotrack.h"
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#include "dat.h"
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#include "fns.h"
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void
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mlock(MLock *l)
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{
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if(l->key != 0 && l->key != 1)
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panic("uninitialized lock");
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if (l->key)
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panic("lock");
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l->key = 1;
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}
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void
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unmlock(MLock *l)
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{
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if(l->key != 0 && l->key != 1)
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panic("uninitialized unlock");
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if (!l->key)
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panic("unlock");
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l->key = 0;
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}
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int
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canmlock(MLock *l)
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{
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if(l->key != 0 && l->key != 1)
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panic("uninitialized canlock");
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if (l->key)
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return 0;
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l->key = 1;
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return 1;
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}
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