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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"
long
fspread(Fid *fid, void *buf, long n, vlong offset)
{
Fcall tx, rx;
void *freep;
uint msize;
msize = fid->fs->msize - IOHDRSZ;
fprint(2, "n %d msize %d\n", n, msize);
if(n > msize)
n = msize;
tx.type = Tread;
tx.fid = fid->fid;
if(offset == -1){
qlock(&fid->lk);
tx.offset = fid->offset;
qunlock(&fid->lk);
}else
tx.offset = offset;
tx.count = n;
fsrpc(fid->fs, &tx, &rx, &freep);
if(rx.type == Rerror){
werrstr("%s", rx.ename);
free(freep);
return -1;
}
if(rx.count){
memmove(buf, rx.data, rx.count);
if(offset == -1){
qlock(&fid->lk);
fid->offset += rx.count;
qunlock(&fid->lk);
}
}
free(freep);
return rx.count;
}
long
fsread(Fid *fid, void *buf, long n)
{
return fspread(fid, buf, n, -1);
}
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