1/* Copyright (C) 1994-2024 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <string.h>
20#include <sys/socket.h>
21#include <hurd.h>
22#include <hurd/fd.h>
23#include <hurd/socket.h>
24#include <sysdep-cancel.h>
25
26/* Read N bytes into BUF through socket FD.
27 If ADDR is not NULL, fill in *ADDR_LEN bytes of it with the address of
28 the sender, and store the actual size of the address in *ADDR_LEN.
29 Returns the number of bytes read or -1 for errors. */
30ssize_t
31__recvfrom (int fd, void *buf, size_t n, int flags, __SOCKADDR_ARG addrarg,
32 socklen_t *addr_len)
33{
34 error_t err;
35 mach_port_t addrport;
36 char *bufp = buf;
37 mach_msg_type_number_t nread = n;
38 mach_port_t *ports;
39 mach_msg_type_number_t nports = 0;
40 char *cdata = NULL;
41 mach_msg_type_number_t clen = 0;
42 struct sockaddr *addr = addrarg.__sockaddr__;
43 int cancel_oldtype;
44
45 cancel_oldtype = LIBC_CANCEL_ASYNC();
46 err = HURD_DPORT_USE_CANCEL (fd, __socket_recv (port, &addrport,
47 flags, &bufp, &nread,
48 &ports, &nports,
49 &cdata, &clen,
50 &flags,
51 n));
52 LIBC_CANCEL_RESET (cancel_oldtype);
53
54 if (err)
55 return __hurd_sockfail (fd, flags, err);
56
57 /* Get address data for the returned address port if requested. */
58 if (addr != NULL && addrport != MACH_PORT_NULL)
59 {
60 char *buf = (char *) addr;
61 mach_msg_type_number_t buflen = *addr_len;
62 int type;
63
64 cancel_oldtype = LIBC_CANCEL_ASYNC();
65 err = __socket_whatis_address (addrport, &type, &buf, &buflen);
66 LIBC_CANCEL_RESET (cancel_oldtype);
67 if (err == EOPNOTSUPP)
68 /* If the protocol server can't tell us the address, just return a
69 zero-length one. */
70 {
71 buf = (char *)addr;
72 buflen = 0;
73 err = 0;
74 }
75
76 if (err)
77 {
78 __mach_port_deallocate (__mach_task_self (), addrport);
79 return __hurd_sockfail (fd, flags, err);
80 }
81
82 if (*addr_len > buflen)
83 *addr_len = buflen;
84
85 if (buf != (char *) addr)
86 {
87 memcpy (addr, buf, *addr_len);
88 __vm_deallocate (__mach_task_self (), (vm_address_t) buf, buflen);
89 }
90
91 if (buflen > 0)
92 addr->sa_family = type;
93 }
94 else if (addr_len != NULL)
95 *addr_len = 0;
96
97 if (MACH_PORT_VALID (addrport))
98 __mach_port_deallocate (__mach_task_self (), addrport);
99
100 /* Toss control data; we don't care. */
101 __vm_deallocate (__mach_task_self (), (vm_address_t) cdata, clen);
102
103 if (bufp != buf)
104 {
105 memcpy (buf, bufp, nread);
106 __vm_deallocate (__mach_task_self (), (vm_address_t) bufp, nread);
107 }
108
109 return nread;
110}
111
112weak_alias (__recvfrom, recvfrom)
113

source code of glibc/sysdeps/mach/hurd/recvfrom.c