56 lines
899 B
C
56 lines
899 B
C
#include <u.h>
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#include <libc.h>
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#include <venti.h>
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void
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vtzeroextend(int type, uchar *buf, uint n, uint nn)
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{
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uchar *p, *ep;
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switch(type&7) {
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case 0:
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memset(buf+n, 0, nn-n);
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break;
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default:
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p = buf + (n/VtScoreSize)*VtScoreSize;
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ep = buf + (nn/VtScoreSize)*VtScoreSize;
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while(p < ep) {
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memmove(p, vtzeroscore, VtScoreSize);
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p += VtScoreSize;
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}
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memset(p, 0, buf+nn-p);
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break;
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}
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}
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uint
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vtzerotruncate(int type, uchar *buf, uint n)
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{
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uchar *p;
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if(type == VtRootType){
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if(n < VtRootSize)
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return n;
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return VtRootSize;
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}
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switch(type&7){
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case 0:
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for(p = buf + n; p > buf; p--) {
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if(p[-1] != 0)
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break;
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}
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return p - buf;
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default:
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/* ignore slop at end of block */
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p = buf + (n/VtScoreSize)*VtScoreSize;
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while(p > buf) {
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if(memcmp(p - VtScoreSize, vtzeroscore, VtScoreSize) != 0)
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break;
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p -= VtScoreSize;
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}
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return p - buf;
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}
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}
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