o5r/plan9port
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add fsseek

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rsc 2005-01-18 18:11:39 +00:00
parent 0fcd970331
commit daefa1a92f
3 changed files with 50 additions and 0 deletions
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3
include/9pclient.h
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@ -22,6 +22,9 @@ CFid *fsopen(CFsys*, char*, int);
int fsopenfd(CFsys*, char*, int);
long fsread(CFid*, void*, long);
long fsreadn(CFid*, void*, long);
long fspread(CFid*, void*, long, vlong);
long fspwrite(CFid*, void*, long, vlong);
vlong fsseek(CFid*, vlong, int);
long fswrite(CFid*, void*, long);
void fsclose(CFid*);
void fsunmount(CFsys*);

1
src/lib9pclient/mkfile
View file

@ -11,6 +11,7 @@ OFILES=\
open.$O\
openfd.$O\
read.$O\
seek.$O\
stat.$O\
walk.$O\
write.$O\

46
src/lib9pclient/seek.c Normal file
View file

@ -0,0 +1,46 @@
#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <9pclient.h>
#include "fsimpl.h"
vlong
fsseek(CFid *fid, vlong n, int whence)
{
Dir *d;
switch(whence){
case 0:
qlock(&fid->lk);
fid->offset = n;
qunlock(&fid->lk);
break;
case 1:
qlock(&fid->lk);
n += fid->offset;
if(n < 0){
qunlock(&fid->lk);
werrstr("negative offset");
return -1;
}
fid->offset = n;
qunlock(&fid->lk);
break;
case 2:
if((d = fsdirfstat(fid)) == nil)
return -1;
n += d->length;
if(n < 0){
werrstr("negative offset");
return -1;
}
qlock(&fid->lk);
fid->offset = n;
qunlock(&fid->lk);
break;
default:
werrstr("bad whence in fsseek");
return -1;
}
return n;
}