1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2016. 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 "erl_interface.h"
#include "erl_connect.h"
/* remove the association between name and its pid */
/* global:unregister_name(name) -> ok */
int erl_global_unregister(int fd, const char *name)
{
char buf[EISMALLBUF];
char *bufp=buf;
char tmpbuf[64];
int index = 0;
erlang_pid *self = erl_self();
erlang_msg msg;
int i;
int version,arity,msglen;
int needunlink, needatom, needdemonitor;
/* make a self pid */
self->num = fd;
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 */
/* make the rpc call */
if (ei_send_reg_encoded(fd,self,"rex",buf,index)) return -1;
/* 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) return -1;
needunlink = 0;
break;
case ERL_DEMONITOR_P-10:
/* got demonitor */
if (!needdemonitor) return -1;
needdemonitor = 0;
break;
case ERL_SEND:
/* got message - does it contain our atom? */
if (!needatom) return -1;
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"))
return -1; /* bad response from other side */
/* we're done here */
return 0;
}
break;
default:
return -1;
}
}
return 0;
}
|
