// RemoveAttr
status_t
FileHandle::RemoveAttr(const char* name)
{
if (fFD < 0)
return B_BAD_VALUE;
return (fs_remove_attr(fFD, name) == 0 ? B_OK : errno);
}
int main(void)
{
char path[300];
int code;
thread_id tid;
system_info sinfo;
thread_info tinfo;
int fd;
int r;
struct{
int lock;
bigtime_t sessionSN;
thread_id tid;
}lockdata;
signal(SIGINT,SIG_IGN); // protection anti-cons
get_system_info(&sinfo);
for(;;){
code=receive_data(&tid,&path,sizeof path);
path[sizeof path-1]=0;
fd=open(path,B_READ_WRITE);
if(fd<0){
send_data(tid,errno,NULL,0);
continue;
}
r=fs_read_attr(fd,AFL_SERVER_NAME,ATTRTYPE,
0,&lockdata,sizeof lockdata);
switch(code){
case AFLMSG_LOCK:
if(r==sizeof lockdata
&& lockdata.lock
&& lockdata.sessionSN==sinfo.boot_time
&& !(get_thread_info(lockdata.tid,&tinfo))){
// le fichier est déjà vérouillé !
close(fd);
send_data(tid,AFLMSG_ISLOCKED,&lockdata.tid,sizeof lockdata.tid);
break;
}
lockdata.lock=1;
lockdata.sessionSN=sinfo.boot_time;
lockdata.tid=tid;
r=fs_write_attr(fd,AFL_SERVER_NAME,ATTRTYPE,
0,&lockdata,sizeof lockdata);
close(fd);
if(r<0)
send_data(tid,errno,0,NULL);
else
send_data(tid,B_OK,0,NULL);
break;
case AFLMSG_UNLOCK:
if(r!=sizeof lockdata
|| !lockdata.lock
|| lockdata.sessionSN!=sinfo.boot_time
|| lockdata.tid!=tid){
// le fichier n'est pas vérouillé par ce thread !
close(fd);
send_data(tid,B_PERMISSION_DENIED,0,NULL);
break;
}
r=fs_remove_attr(fd,AFL_SERVER_NAME);
close(fd);
if(r<0)
send_data(tid,errno,0,NULL);
else
send_data(tid,B_OK,0,NULL);
break;
default:
close(fd);
send_data(tid,B_BAD_VALUE,0,NULL);
}
}
return 0;
}
