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/* Copyright (C) 2003 Russ Cox, Massachusetts Institute of Technology */
/* See COPYRIGHT */
#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <fs.h>
#include "fsimpl.h"
static long
_fspwrite(Fid *fid, void *buf, long n, vlong offset)
{
Fcall tx, rx;
void *freep;
tx.type = Twrite;
tx.fid = fid->fid;
if(offset == -1){
qlock(&fid->lk);
tx.offset = fid->offset;
qunlock(&fid->lk);
}else
tx.offset = offset;
tx.count = n;
tx.data = buf;
if(fsrpc(fid->fs, &tx, &rx, &freep) < 0)
return -1;
if(rx.type == Rerror){
werrstr("%s", rx.ename);
free(freep);
return -1;
}
if(offset == -1 && rx.count){
qlock(&fid->lk);
fid->offset += rx.count;
qunlock(&fid->lk);
}
free(freep);
return rx.count;
}
long
fspwrite(Fid *fid, void *buf, long n, vlong offset)
{
long tot, want, got, first;
uint msize;
msize = fid->fs->msize - IOHDRSZ;
tot = 0;
first = 1;
while(tot < n || first){
want = n - tot;
if(want > msize)
want = msize;
got = _fspwrite(fid, buf, want, offset);
first = 0;
if(got < 0){
if(tot == 0)
return got;
break;
}
tot += got;
if(offset != -1)
offset += got;
}
return tot;
}
long
fswrite(Fid *fid, void *buf, long n)
{
return fspwrite(fid, buf, n, -1);
}
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