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/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2021. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* %CopyrightEnd%
*/
#include <string.h>
#include "eidef.h" /* Has to be first */
#include "eiext.h"
#include "eisend.h"
#include "eirecv.h"
#include "ei_connect_int.h"
#include "ei_connect.h"
#include "ei.h"
#include "ei_internal.h"
/* remove the association between name and its pid */
/* global:unregister_name(name) -> ok */
int ei_global_unregister(ei_cnode *ec, int fd, const char *name)
{
char buf[EISMALLBUF];
char *bufp=buf;
char tmpbuf[64];
int index = 0;
erlang_pid *self = ei_self(ec);
erlang_msg msg;
int i;
int version,arity,msglen;
int needunlink, needatom, needdemonitor;
if (ei_encode_version(buf,&index)
|| ei_encode_tuple_header(buf,&index,2)
|| ei_encode_pid(buf,&index,self) /* PidFrom */
|| ei_encode_tuple_header(buf,&index,5)
|| ei_encode_atom(buf,&index,"call") /* call */
|| ei_encode_atom(buf,&index,"global") /* Mod */
|| ei_encode_atom(buf,&index,"unregister_name_external") /* Fun */
|| ei_encode_list_header(buf,&index,1) /* Args: [ name ] */
|| ei_encode_atom(buf,&index,name)
|| ei_encode_empty_list(buf,&index)
|| ei_encode_atom(buf,&index,"user")) { /* user */
EI_CONN_SAVE_ERRNO__(EINVAL);
return ERL_ERROR;
}
/* make the rpc call */
if (ei_send_reg_encoded(fd,self,"rex",buf,index)) return ERL_ERROR;
/* get the reply: expect unlink and an atom, or just an atom */
needunlink = needatom = needdemonitor = 1;
while (1) {
/* get message */
while (1) {
index = EISMALLBUF;
if (!(i = ei_recv_internal(fd,&bufp,&index,&msg,&msglen,1,0))) continue;
else break;
}
switch (i) {
case ERL_UNLINK:
/* got unlink */
if (!needunlink) {
EI_CONN_SAVE_ERRNO__(EBADMSG);
return ERL_ERROR;
}
needunlink = 0;
break;
case ERL_DEMONITOR_P-10:
/* got demonitor */
if (!needdemonitor) {
EI_CONN_SAVE_ERRNO__(EBADMSG);
return ERL_ERROR;
}
needdemonitor = 0;
break;
case ERL_SEND:
/* got message - does it contain our atom? */
if (!needatom) {
EI_CONN_SAVE_ERRNO__(EBADMSG);
return ERL_ERROR;
}
else {
/* expecting { rex, ok } */
index = 0;
if (ei_decode_version(buf,&index,&version)
|| ei_decode_tuple_header(buf,&index,&arity)
|| (arity != 2)
|| ei_decode_atom(buf,&index,tmpbuf)
|| strcmp(tmpbuf,"rex")
|| ei_decode_atom(buf,&index,tmpbuf)
|| strcmp(tmpbuf,"ok")) {
EI_CONN_SAVE_ERRNO__(EBADMSG);
return ERL_ERROR; /* bad response from other side */
}
/* we're done here */
return 0;
}
break;
default:
EI_CONN_SAVE_ERRNO__(EBADMSG);
return ERL_ERROR;
}
}
return 0;
}
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