mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-30 14:31:14 +00:00
c3b287be74
During critical sections, signal handling is deferred and thus RPCs return EINTR, even if SA_RESTART is set. We thus have to restart the whole critical section in that case. This also adds HURD_CRITICAL_UNLOCK in the cases where one wants to break the section in the middle.
125 lines
3.5 KiB
C
125 lines
3.5 KiB
C
/* _hurd_socket_server - Find the server for a socket domain.
|
||
Copyright (C) 1991-2021 Free Software Foundation, Inc.
|
||
This file is part of the GNU C Library.
|
||
|
||
The GNU C Library is free software; you can redistribute it and/or
|
||
modify it under the terms of the GNU Lesser General Public
|
||
License as published by the Free Software Foundation; either
|
||
version 2.1 of the License, or (at your option) any later version.
|
||
|
||
The GNU C Library is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
Lesser General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Lesser General Public
|
||
License along with the GNU C Library; if not, see
|
||
<https://www.gnu.org/licenses/>. */
|
||
|
||
#include <hurd.h>
|
||
#include <sys/socket.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include <hurd/paths.h>
|
||
#include <stdio.h>
|
||
#include <_itoa.h>
|
||
#include <lock-intern.h> /* For `struct mutex'. */
|
||
#include "hurdmalloc.h" /* XXX */
|
||
|
||
static struct mutex lock;
|
||
|
||
static file_t *servers;
|
||
static int max_domain = -1;
|
||
|
||
/* Return a port to the socket server for DOMAIN.
|
||
Socket servers translate nodes in the directory _SERVERS_SOCKET
|
||
(canonically /servers/socket). These naming point nodes are named
|
||
by the simplest decimal representation of the socket domain number,
|
||
for example "/servers/socket/3".
|
||
|
||
Socket servers are assumed not to change very often.
|
||
The library keeps all the server socket ports it has ever looked up,
|
||
and does not look them up in /servers/socket more than once. */
|
||
|
||
socket_t
|
||
_hurd_socket_server (int domain, int dead)
|
||
{
|
||
socket_t server;
|
||
|
||
if (domain < 0)
|
||
{
|
||
errno = EAFNOSUPPORT;
|
||
return MACH_PORT_NULL;
|
||
}
|
||
|
||
retry:
|
||
HURD_CRITICAL_BEGIN;
|
||
__mutex_lock (&lock);
|
||
|
||
if (domain > max_domain)
|
||
{
|
||
error_t save = errno;
|
||
file_t *new = realloc (servers, (domain + 1) * sizeof (file_t));
|
||
if (new != NULL)
|
||
{
|
||
do
|
||
new[++max_domain] = MACH_PORT_NULL;
|
||
while (max_domain < domain);
|
||
servers = new;
|
||
}
|
||
else
|
||
/* No space to cache the port; we will just fetch it anew below. */
|
||
errno = save;
|
||
}
|
||
|
||
if (dead && domain <= max_domain)
|
||
{
|
||
/* The user says the port we returned earlier (now in SERVERS[DOMAIN])
|
||
was dead. Clear the cache and fetch a new one below. */
|
||
__mach_port_deallocate (__mach_task_self (), servers[domain]);
|
||
servers[domain] = MACH_PORT_NULL;
|
||
}
|
||
|
||
if (domain > max_domain || servers[domain] == MACH_PORT_NULL)
|
||
{
|
||
char name[sizeof (_SERVERS_SOCKET) + 100];
|
||
char *np = &name[sizeof (name)];
|
||
*--np = '\0';
|
||
np = _itoa (domain, np, 10, 0);
|
||
*--np = '/';
|
||
np -= sizeof (_SERVERS_SOCKET) - 1;
|
||
memcpy (np, _SERVERS_SOCKET, sizeof (_SERVERS_SOCKET) - 1);
|
||
server = __file_name_lookup (np, 0, 0);
|
||
if (domain <= max_domain)
|
||
servers[domain] = server;
|
||
}
|
||
else
|
||
server = servers[domain];
|
||
|
||
if (server == MACH_PORT_NULL && errno == ENOENT)
|
||
/* If the server node is absent, we don't support that protocol. */
|
||
errno = EAFNOSUPPORT;
|
||
|
||
__mutex_unlock (&lock);
|
||
HURD_CRITICAL_END;
|
||
if (server == MACH_PORT_NULL && errno == EINTR)
|
||
/* Got a signal while inside an RPC of the critical section, retry again */
|
||
goto retry;
|
||
|
||
return server;
|
||
}
|
||
|
||
static void
|
||
init (void)
|
||
{
|
||
int i;
|
||
|
||
__mutex_init (&lock);
|
||
|
||
for (i = 0; i < max_domain; ++i)
|
||
servers[i] = MACH_PORT_NULL;
|
||
|
||
(void) &init; /* Avoid "defined but not used" warning. */
|
||
}
|
||
text_set_element (_hurd_preinit_hook, init);
|