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I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
1660 lines
49 KiB
C
1660 lines
49 KiB
C
/* Copyright (C) 1991-2021 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <lock-intern.h> /* For `struct mutex'. */
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#include <pthreadP.h>
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#include <mach.h>
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#include <mach/thread_switch.h>
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#include <mach/mig_support.h>
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#include <mach/vm_param.h>
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#include <hurd.h>
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#include <hurd/id.h>
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#include <hurd/signal.h>
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#include "hurdfault.h"
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#include "hurdmalloc.h" /* XXX */
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#include "../locale/localeinfo.h"
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#include <libc-diag.h>
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const char *_hurdsig_getenv (const char *);
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struct mutex _hurd_siglock;
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int _hurd_stopped;
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/* Port that receives signals and other miscellaneous messages. */
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mach_port_t _hurd_msgport;
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/* Thread listening on it. */
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thread_t _hurd_msgport_thread;
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/* These are set up by _hurdsig_init. */
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unsigned long int __hurd_sigthread_stack_base;
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unsigned long int __hurd_sigthread_stack_end;
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/* Linked-list of per-thread signal state. */
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struct hurd_sigstate *_hurd_sigstates;
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/* Sigstate for the task-global signals. */
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struct hurd_sigstate *_hurd_global_sigstate;
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/* Timeout for RPC's after interrupt_operation. */
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mach_msg_timeout_t _hurd_interrupted_rpc_timeout = 60000;
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static void
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default_sigaction (struct sigaction actions[NSIG])
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{
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int signo;
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__sigemptyset (&actions[0].sa_mask);
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actions[0].sa_flags = SA_RESTART;
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actions[0].sa_handler = SIG_DFL;
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for (signo = 1; signo < NSIG; ++signo)
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actions[signo] = actions[0];
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}
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struct hurd_sigstate *
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_hurd_thread_sigstate (thread_t thread)
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{
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struct hurd_sigstate *ss;
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__mutex_lock (&_hurd_siglock);
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for (ss = _hurd_sigstates; ss != NULL; ss = ss->next)
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if (ss->thread == thread)
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break;
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if (ss == NULL)
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{
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ss = malloc (sizeof (*ss));
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if (ss == NULL)
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__libc_fatal ("hurd: Can't allocate sigstate\n");
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__spin_lock_init (&ss->critical_section_lock);
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__spin_lock_init (&ss->lock);
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ss->thread = thread;
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/* Initialize default state. */
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__sigemptyset (&ss->blocked);
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__sigemptyset (&ss->pending);
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memset (&ss->sigaltstack, 0, sizeof (ss->sigaltstack));
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ss->sigaltstack.ss_flags |= SS_DISABLE;
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ss->preemptors = NULL;
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ss->suspended = MACH_PORT_NULL;
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ss->intr_port = MACH_PORT_NULL;
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ss->context = NULL;
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ss->active_resources = NULL;
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ss->cancel = 0;
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ss->cancel_hook = NULL;
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if (thread == MACH_PORT_NULL)
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{
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/* Process-wide sigstate, use the system defaults. */
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default_sigaction (ss->actions);
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/* The global sigstate is not added to the _hurd_sigstates list.
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It is created with _hurd_thread_sigstate (MACH_PORT_NULL)
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but should be accessed through _hurd_global_sigstate. */
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}
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else
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{
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error_t err;
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/* Use the global actions as a default for new threads. */
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struct hurd_sigstate *s = _hurd_global_sigstate;
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if (s)
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{
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__spin_lock (&s->lock);
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memcpy (ss->actions, s->actions, sizeof (s->actions));
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__spin_unlock (&s->lock);
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}
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else
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default_sigaction (ss->actions);
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ss->next = _hurd_sigstates;
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_hurd_sigstates = ss;
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err = __mach_port_mod_refs (__mach_task_self (), thread,
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MACH_PORT_RIGHT_SEND, 1);
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if (err)
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__libc_fatal ("hurd: Can't add reference on Mach thread\n");
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}
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}
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__mutex_unlock (&_hurd_siglock);
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return ss;
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}
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libc_hidden_def (_hurd_thread_sigstate)
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/* Destroy a sigstate structure. Called by libpthread just before the
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* corresponding thread is terminated. */
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void
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_hurd_sigstate_delete (thread_t thread)
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{
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struct hurd_sigstate **ssp, *ss;
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__mutex_lock (&_hurd_siglock);
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for (ssp = &_hurd_sigstates; *ssp; ssp = &(*ssp)->next)
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if ((*ssp)->thread == thread)
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break;
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ss = *ssp;
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if (ss)
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*ssp = ss->next;
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__mutex_unlock (&_hurd_siglock);
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if (ss)
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{
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if (ss->thread != MACH_PORT_NULL)
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__mach_port_deallocate (__mach_task_self (), ss->thread);
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free (ss);
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}
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}
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/* Make SS a global receiver, with pthread signal semantics. */
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void
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_hurd_sigstate_set_global_rcv (struct hurd_sigstate *ss)
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{
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assert (ss->thread != MACH_PORT_NULL);
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ss->actions[0].sa_handler = SIG_IGN;
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}
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/* Check whether SS is a global receiver. */
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static int
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sigstate_is_global_rcv (const struct hurd_sigstate *ss)
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{
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return (_hurd_global_sigstate != NULL)
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&& (ss->actions[0].sa_handler == SIG_IGN);
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}
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libc_hidden_def (_hurd_sigstate_delete)
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/* Lock/unlock a hurd_sigstate structure. If the accessors below require
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it, the global sigstate will be locked as well. */
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void
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_hurd_sigstate_lock (struct hurd_sigstate *ss)
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{
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if (sigstate_is_global_rcv (ss))
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__spin_lock (&_hurd_global_sigstate->lock);
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__spin_lock (&ss->lock);
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}
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void
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_hurd_sigstate_unlock (struct hurd_sigstate *ss)
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{
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__spin_unlock (&ss->lock);
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if (sigstate_is_global_rcv (ss))
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__spin_unlock (&_hurd_global_sigstate->lock);
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}
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libc_hidden_def (_hurd_sigstate_set_global_rcv)
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/* Retreive a thread's full set of pending signals, including the global
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ones if appropriate. SS must be locked. */
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sigset_t
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_hurd_sigstate_pending (const struct hurd_sigstate *ss)
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{
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sigset_t pending = ss->pending;
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if (sigstate_is_global_rcv (ss))
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__sigorset (&pending, &pending, &_hurd_global_sigstate->pending);
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return pending;
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}
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/* Clear a pending signal and return the associated detailed
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signal information. SS must be locked, and must have signal SIGNO
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pending, either directly or through the global sigstate. */
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static struct hurd_signal_detail
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sigstate_clear_pending (struct hurd_sigstate *ss, int signo)
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{
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if (sigstate_is_global_rcv (ss)
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&& __sigismember (&_hurd_global_sigstate->pending, signo))
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{
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__sigdelset (&_hurd_global_sigstate->pending, signo);
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return _hurd_global_sigstate->pending_data[signo];
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}
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assert (__sigismember (&ss->pending, signo));
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__sigdelset (&ss->pending, signo);
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return ss->pending_data[signo];
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}
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libc_hidden_def (_hurd_sigstate_lock)
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libc_hidden_def (_hurd_sigstate_unlock)
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/* Retreive a thread's action vector. SS must be locked. */
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struct sigaction *
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_hurd_sigstate_actions (struct hurd_sigstate *ss)
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{
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if (sigstate_is_global_rcv (ss))
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return _hurd_global_sigstate->actions;
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else
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return ss->actions;
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}
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libc_hidden_def (_hurd_sigstate_pending)
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/* Signal delivery itself is on this page. */
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#include <hurd/fd.h>
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#include <hurd/crash.h>
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#include <hurd/resource.h>
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#include <hurd/paths.h>
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#include <setjmp.h>
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#include <fcntl.h>
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#include <sys/wait.h>
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#include <thread_state.h>
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#include <hurd/msg_server.h>
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#include <hurd/msg_reply.h> /* For __msg_sig_post_reply. */
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#include <hurd/interrupt.h>
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#include <assert.h>
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#include <unistd.h>
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/* Call the crash dump server to mummify us before we die.
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Returns nonzero if a core file was written. */
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static int
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write_corefile (int signo, const struct hurd_signal_detail *detail)
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{
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error_t err;
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mach_port_t coreserver;
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file_t file, coredir;
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const char *name;
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/* Don't bother locking since we just read the one word. */
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rlim_t corelimit = _hurd_rlimits[RLIMIT_CORE].rlim_cur;
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if (corelimit == 0)
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/* No core dumping, thank you very much. Note that this makes
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`ulimit -c 0' prevent crash-suspension too, which is probably
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what the user wanted. */
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return 0;
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/* XXX RLIMIT_CORE:
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When we have a protocol to make the server return an error
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for RLIMIT_FSIZE, then tell the corefile fs server the RLIMIT_CORE
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value in place of the RLIMIT_FSIZE value. */
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/* First get a port to the core dumping server. */
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coreserver = MACH_PORT_NULL;
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name = _hurdsig_getenv ("CRASHSERVER");
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if (name != NULL)
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coreserver = __file_name_lookup (name, 0, 0);
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if (coreserver == MACH_PORT_NULL)
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coreserver = __file_name_lookup (_SERVERS_CRASH, 0, 0);
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if (coreserver == MACH_PORT_NULL)
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return 0;
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/* Get a port to the directory where the new core file will reside. */
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file = MACH_PORT_NULL;
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name = _hurdsig_getenv ("COREFILE");
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if (name == NULL)
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name = "core";
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coredir = __file_name_split (name, (char **) &name);
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if (coredir != MACH_PORT_NULL)
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/* Create the new file, but don't link it into the directory yet. */
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__dir_mkfile (coredir, O_WRONLY|O_CREAT,
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0600 & ~_hurd_umask, /* XXX ? */
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&file);
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/* Call the core dumping server to write the core file. */
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err = __crash_dump_task (coreserver,
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__mach_task_self (),
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file,
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signo, detail->code, detail->error,
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detail->exc, detail->exc_code, detail->exc_subcode,
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_hurd_ports[INIT_PORT_CTTYID].port,
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MACH_MSG_TYPE_COPY_SEND);
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__mach_port_deallocate (__mach_task_self (), coreserver);
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if (! err && file != MACH_PORT_NULL)
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/* The core dump into FILE succeeded, so now link it into the
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directory. */
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err = __dir_link (coredir, file, name, 1);
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__mach_port_deallocate (__mach_task_self (), file);
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__mach_port_deallocate (__mach_task_self (), coredir);
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return !err && file != MACH_PORT_NULL;
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}
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/* The lowest-numbered thread state flavor value is 1,
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so we use bit 0 in machine_thread_all_state.set to
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record whether we have done thread_abort. */
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#define THREAD_ABORTED 1
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/* SS->thread is suspended. Abort the thread and get its basic state. */
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static void
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abort_thread (struct hurd_sigstate *ss, struct machine_thread_all_state *state,
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void (*reply) (void))
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{
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assert (ss->thread != MACH_PORT_NULL);
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if (!(state->set & THREAD_ABORTED))
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{
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error_t err = __thread_abort (ss->thread);
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assert_perror (err);
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/* Clear all thread state flavor set bits, because thread_abort may
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have changed the state. */
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state->set = THREAD_ABORTED;
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}
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if (reply)
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(*reply) ();
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machine_get_basic_state (ss->thread, state);
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}
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/* Find the location of the MiG reply port cell in use by the thread whose
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state is described by THREAD_STATE. If SIGTHREAD is nonzero, make sure
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that this location can be set without faulting, or else return NULL. */
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static mach_port_t *
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interrupted_reply_port_location (thread_t thread,
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struct machine_thread_all_state *thread_state,
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int sigthread)
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{
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mach_port_t *portloc = &THREAD_TCB(thread, thread_state)->reply_port;
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if (sigthread && _hurdsig_catch_memory_fault (portloc))
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/* Faulted trying to read the TCB. */
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return NULL;
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DIAG_PUSH_NEEDS_COMMENT;
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/* GCC 6 and before seem to be confused by the setjmp call inside
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_hurdsig_catch_memory_fault and think that we may be returning a second
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time to here with portloc uninitialized (but we never do). */
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DIAG_IGNORE_NEEDS_COMMENT (6, "-Wmaybe-uninitialized");
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/* Fault now if this pointer is bogus. */
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*(volatile mach_port_t *) portloc = *portloc;
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DIAG_POP_NEEDS_COMMENT;
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if (sigthread)
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_hurdsig_end_catch_fault ();
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return portloc;
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}
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#include <hurd/sigpreempt.h>
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#include <intr-msg.h>
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/* Timeout on interrupt_operation calls. */
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mach_msg_timeout_t _hurdsig_interrupt_timeout = 1000;
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/* SS->thread is suspended.
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Abort any interruptible RPC operation the thread is doing.
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This uses only the constant member SS->thread and the unlocked, atomically
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set member SS->intr_port, so no locking is needed.
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If successfully sent an interrupt_operation and therefore the thread should
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wait for its pending RPC to return (possibly EINTR) before taking the
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incoming signal, returns the reply port to be received on. Otherwise
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returns MACH_PORT_NULL.
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SIGNO is used to find the applicable SA_RESTART bit. If SIGNO is zero,
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the RPC fails with EINTR instead of restarting (thread_cancel).
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*STATE_CHANGE is set nonzero if STATE->basic was modified and should
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be applied back to the thread if it might ever run again, else zero. */
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mach_port_t
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_hurdsig_abort_rpcs (struct hurd_sigstate *ss, int signo, int sigthread,
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struct machine_thread_all_state *state, int *state_change,
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void (*reply) (void))
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{
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extern const void _hurd_intr_rpc_msg_about_to;
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extern const void _hurd_intr_rpc_msg_in_trap;
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mach_port_t rcv_port = MACH_PORT_NULL;
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mach_port_t intr_port;
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*state_change = 0;
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intr_port = ss->intr_port;
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if (intr_port == MACH_PORT_NULL)
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/* No interruption needs done. */
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return MACH_PORT_NULL;
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/* Abort the thread's kernel context, so any pending message send or
|
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receive completes immediately or aborts. */
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abort_thread (ss, state, reply);
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|
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if (state->basic.PC >= (natural_t) &_hurd_intr_rpc_msg_about_to
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&& state->basic.PC < (natural_t) &_hurd_intr_rpc_msg_in_trap)
|
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{
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/* The thread is about to do the RPC, but hasn't yet entered
|
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mach_msg. Mutate the thread's state so it knows not to try
|
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the RPC. */
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INTR_MSG_BACK_OUT (&state->basic);
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MACHINE_THREAD_STATE_SET_PC (&state->basic,
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&_hurd_intr_rpc_msg_in_trap);
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state->basic.SYSRETURN = MACH_SEND_INTERRUPTED;
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*state_change = 1;
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}
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else if (state->basic.PC == (natural_t) &_hurd_intr_rpc_msg_in_trap
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||
/* The thread was blocked in the system call. After thread_abort,
|
||
the return value register indicates what state the RPC was in
|
||
when interrupted. */
|
||
&& state->basic.SYSRETURN == MACH_RCV_INTERRUPTED)
|
||
{
|
||
/* The RPC request message was sent and the thread was waiting for
|
||
the reply message; now the message receive has been aborted, so
|
||
the mach_msg call will return MACH_RCV_INTERRUPTED. We must tell
|
||
the server to interrupt the pending operation. The thread must
|
||
wait for the reply message before running the signal handler (to
|
||
guarantee that the operation has finished being interrupted), so
|
||
our nonzero return tells the trampoline code to finish the message
|
||
receive operation before running the handler. */
|
||
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||
mach_port_t *reply = interrupted_reply_port_location (ss->thread,
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||
state,
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||
sigthread);
|
||
error_t err = __interrupt_operation (intr_port, _hurdsig_interrupt_timeout);
|
||
|
||
if (err)
|
||
{
|
||
if (reply)
|
||
{
|
||
/* The interrupt didn't work.
|
||
Destroy the receive right the thread is blocked on. */
|
||
__mach_port_destroy (__mach_task_self (), *reply);
|
||
*reply = MACH_PORT_NULL;
|
||
}
|
||
|
||
/* The system call return value register now contains
|
||
MACH_RCV_INTERRUPTED; when mach_msg resumes, it will retry the
|
||
call. Since we have just destroyed the receive right, the
|
||
retry will fail with MACH_RCV_INVALID_NAME. Instead, just
|
||
change the return value here to EINTR so mach_msg will not
|
||
retry and the EINTR error code will propagate up. */
|
||
state->basic.SYSRETURN = EINTR;
|
||
*state_change = 1;
|
||
}
|
||
else if (reply)
|
||
rcv_port = *reply;
|
||
|
||
/* All threads whose RPCs were interrupted by the interrupt_operation
|
||
call above will retry their RPCs unless we clear SS->intr_port.
|
||
So we clear it for the thread taking a signal when SA_RESTART is
|
||
clear, so that its call returns EINTR. */
|
||
if (! signo || !(_hurd_sigstate_actions (ss) [signo].sa_flags & SA_RESTART))
|
||
ss->intr_port = MACH_PORT_NULL;
|
||
}
|
||
|
||
return rcv_port;
|
||
}
|
||
|
||
|
||
/* Abort the RPCs being run by all threads but this one;
|
||
all other threads should be suspended. If LIVE is nonzero, those
|
||
threads may run again, so they should be adjusted as necessary to be
|
||
happy when resumed. STATE is clobbered as a scratch area; its initial
|
||
contents are ignored, and its contents on return are not useful. */
|
||
|
||
static void
|
||
abort_all_rpcs (int signo, struct machine_thread_all_state *state, int live)
|
||
{
|
||
/* We can just loop over the sigstates. Any thread doing something
|
||
interruptible must have one. We needn't bother locking because all
|
||
other threads are stopped. */
|
||
|
||
struct hurd_sigstate *ss;
|
||
size_t nthreads;
|
||
mach_port_t *reply_ports;
|
||
|
||
/* First loop over the sigstates to count them.
|
||
We need to know how big a vector we will need for REPLY_PORTS. */
|
||
nthreads = 0;
|
||
for (ss = _hurd_sigstates; ss != NULL; ss = ss->next)
|
||
++nthreads;
|
||
|
||
reply_ports = alloca (nthreads * sizeof *reply_ports);
|
||
|
||
nthreads = 0;
|
||
for (ss = _hurd_sigstates; ss != NULL; ss = ss->next, ++nthreads)
|
||
if (ss->thread == _hurd_msgport_thread)
|
||
reply_ports[nthreads] = MACH_PORT_NULL;
|
||
else
|
||
{
|
||
int state_changed;
|
||
state->set = 0; /* Reset scratch area. */
|
||
|
||
/* Abort any operation in progress with interrupt_operation.
|
||
Record the reply port the thread is waiting on.
|
||
We will wait for all the replies below. */
|
||
reply_ports[nthreads] = _hurdsig_abort_rpcs (ss, signo, 1,
|
||
state, &state_changed,
|
||
NULL);
|
||
if (live)
|
||
{
|
||
if (reply_ports[nthreads] != MACH_PORT_NULL)
|
||
{
|
||
/* We will wait for the reply to this RPC below, so the
|
||
thread must issue a new RPC rather than waiting for the
|
||
reply to the one it sent. */
|
||
state->basic.SYSRETURN = EINTR;
|
||
state_changed = 1;
|
||
}
|
||
if (state_changed)
|
||
/* Aborting the RPC needed to change this thread's state,
|
||
and it might ever run again. So write back its state. */
|
||
__thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR,
|
||
(natural_t *) &state->basic,
|
||
MACHINE_THREAD_STATE_COUNT);
|
||
}
|
||
}
|
||
|
||
/* Wait for replies from all the successfully interrupted RPCs. */
|
||
while (nthreads-- > 0)
|
||
if (reply_ports[nthreads] != MACH_PORT_NULL)
|
||
{
|
||
error_t err;
|
||
mach_msg_header_t head;
|
||
err = __mach_msg (&head, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0, sizeof head,
|
||
reply_ports[nthreads],
|
||
_hurd_interrupted_rpc_timeout, MACH_PORT_NULL);
|
||
switch (err)
|
||
{
|
||
case MACH_RCV_TIMED_OUT:
|
||
case MACH_RCV_TOO_LARGE:
|
||
break;
|
||
|
||
default:
|
||
assert_perror (err);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Wake up any sigsuspend or pselect call that is blocking SS->thread. SS must
|
||
be locked. */
|
||
static void
|
||
wake_sigsuspend (struct hurd_sigstate *ss)
|
||
{
|
||
error_t err;
|
||
mach_msg_header_t msg;
|
||
|
||
if (ss->suspended == MACH_PORT_NULL)
|
||
return;
|
||
|
||
/* There is a sigsuspend waiting. Tell it to wake up. */
|
||
msg.msgh_bits = MACH_MSGH_BITS (MACH_MSG_TYPE_MAKE_SEND, 0);
|
||
msg.msgh_remote_port = ss->suspended;
|
||
msg.msgh_local_port = MACH_PORT_NULL;
|
||
/* These values do not matter. */
|
||
msg.msgh_id = 8675309; /* Jenny, Jenny. */
|
||
ss->suspended = MACH_PORT_NULL;
|
||
err = __mach_msg (&msg, MACH_SEND_MSG, sizeof msg, 0,
|
||
MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE,
|
||
MACH_PORT_NULL);
|
||
assert_perror (err);
|
||
}
|
||
|
||
struct hurd_signal_preemptor *_hurdsig_preemptors = 0;
|
||
sigset_t _hurdsig_preempted_set;
|
||
|
||
/* XXX temporary to deal with spelling fix */
|
||
weak_alias (_hurdsig_preemptors, _hurdsig_preempters)
|
||
|
||
/* Mask of stop signals. */
|
||
#define STOPSIGS (__sigmask (SIGTTIN) | __sigmask (SIGTTOU) \
|
||
| __sigmask (SIGSTOP) | __sigmask (SIGTSTP))
|
||
|
||
/* Actual delivery of a single signal. Called with SS unlocked. When
|
||
the signal is delivered, return SS, locked (or, if SS was originally
|
||
_hurd_global_sigstate, the sigstate of the actual thread the signal
|
||
was delivered to). If the signal is being traced, return NULL with
|
||
SS unlocked. */
|
||
static struct hurd_sigstate *
|
||
post_signal (struct hurd_sigstate *ss,
|
||
int signo, struct hurd_signal_detail *detail,
|
||
int untraced, void (*reply) (void))
|
||
{
|
||
struct machine_thread_all_state thread_state;
|
||
enum { stop, ignore, core, term, handle } act;
|
||
int ss_suspended;
|
||
|
||
/* sigaction for preemptors */
|
||
struct sigaction preempt_sigaction = {
|
||
.sa_flags = SA_RESTART
|
||
};
|
||
|
||
struct sigaction *action;
|
||
|
||
/* Mark the signal as pending. */
|
||
void mark_pending (void)
|
||
{
|
||
__sigaddset (&ss->pending, signo);
|
||
/* Save the details to be given to the handler when SIGNO is
|
||
unblocked. */
|
||
ss->pending_data[signo] = *detail;
|
||
}
|
||
|
||
/* Suspend the process with SIGNO. */
|
||
void suspend (void)
|
||
{
|
||
/* Stop all other threads and mark ourselves stopped. */
|
||
__USEPORT (PROC,
|
||
({
|
||
/* Hold the siglock while stopping other threads to be
|
||
sure it is not held by another thread afterwards. */
|
||
__mutex_lock (&_hurd_siglock);
|
||
__proc_dostop (port, _hurd_msgport_thread);
|
||
__mutex_unlock (&_hurd_siglock);
|
||
abort_all_rpcs (signo, &thread_state, 1);
|
||
reply ();
|
||
__proc_mark_stop (port, signo, detail->code);
|
||
}));
|
||
_hurd_stopped = 1;
|
||
}
|
||
/* Resume the process after a suspension. */
|
||
void resume (void)
|
||
{
|
||
/* Resume the process from being stopped. */
|
||
thread_t *threads;
|
||
mach_msg_type_number_t nthreads, i;
|
||
error_t err;
|
||
|
||
if (! _hurd_stopped)
|
||
return;
|
||
|
||
/* Tell the proc server we are continuing. */
|
||
__USEPORT (PROC, __proc_mark_cont (port));
|
||
/* Fetch ports to all our threads and resume them. */
|
||
err = __task_threads (__mach_task_self (), &threads, &nthreads);
|
||
assert_perror (err);
|
||
for (i = 0; i < nthreads; ++i)
|
||
{
|
||
if (act == handle && threads[i] == ss->thread)
|
||
{
|
||
/* The thread that will run the handler is kept suspended. */
|
||
ss_suspended = 1;
|
||
}
|
||
else if (threads[i] != _hurd_msgport_thread)
|
||
{
|
||
err = __thread_resume (threads[i]);
|
||
assert_perror (err);
|
||
}
|
||
err = __mach_port_deallocate (__mach_task_self (),
|
||
threads[i]);
|
||
assert_perror (err);
|
||
}
|
||
__vm_deallocate (__mach_task_self (),
|
||
(vm_address_t) threads,
|
||
nthreads * sizeof *threads);
|
||
_hurd_stopped = 0;
|
||
}
|
||
|
||
error_t err;
|
||
sighandler_t handler;
|
||
|
||
if (signo == 0)
|
||
{
|
||
if (untraced)
|
||
{
|
||
/* This is PTRACE_CONTINUE. */
|
||
act = ignore;
|
||
resume ();
|
||
}
|
||
|
||
/* This call is just to check for pending signals. */
|
||
_hurd_sigstate_lock (ss);
|
||
return ss;
|
||
}
|
||
|
||
thread_state.set = 0; /* We know nothing. */
|
||
|
||
_hurd_sigstate_lock (ss);
|
||
|
||
/* If this is a global signal, try to find a thread ready to accept
|
||
it right away. This is especially important for untraced signals,
|
||
since going through the global pending mask would de-untrace them. */
|
||
if (ss->thread == MACH_PORT_NULL)
|
||
{
|
||
struct hurd_sigstate *rss;
|
||
|
||
__mutex_lock (&_hurd_siglock);
|
||
for (rss = _hurd_sigstates; rss != NULL; rss = rss->next)
|
||
{
|
||
if (! sigstate_is_global_rcv (rss))
|
||
continue;
|
||
|
||
/* The global sigstate is already locked. */
|
||
__spin_lock (&rss->lock);
|
||
if (! __sigismember (&rss->blocked, signo))
|
||
{
|
||
ss = rss;
|
||
break;
|
||
}
|
||
__spin_unlock (&rss->lock);
|
||
}
|
||
__mutex_unlock (&_hurd_siglock);
|
||
}
|
||
|
||
/* We want the preemptors to be able to update the blocking mask
|
||
without affecting the delivery of this signal, so we save the
|
||
current value to test against later. */
|
||
sigset_t blocked = ss->blocked;
|
||
|
||
/* Check for a preempted signal. Preempted signals can arrive during
|
||
critical sections. */
|
||
{
|
||
inline sighandler_t try_preemptor (struct hurd_signal_preemptor *pe)
|
||
{ /* PE cannot be null. */
|
||
do
|
||
{
|
||
if (HURD_PREEMPT_SIGNAL_P (pe, signo, detail->exc_subcode))
|
||
{
|
||
if (pe->preemptor)
|
||
{
|
||
sighandler_t handler = (*pe->preemptor) (pe, ss,
|
||
&signo, detail);
|
||
if (handler != SIG_ERR)
|
||
return handler;
|
||
}
|
||
else
|
||
return pe->handler;
|
||
}
|
||
pe = pe->next;
|
||
} while (pe != 0);
|
||
return SIG_ERR;
|
||
}
|
||
|
||
handler = ss->preemptors ? try_preemptor (ss->preemptors) : SIG_ERR;
|
||
|
||
/* If no thread-specific preemptor, check for a global one. */
|
||
if (handler == SIG_ERR && __sigismember (&_hurdsig_preempted_set, signo))
|
||
{
|
||
__mutex_lock (&_hurd_siglock);
|
||
handler = try_preemptor (_hurdsig_preemptors);
|
||
__mutex_unlock (&_hurd_siglock);
|
||
}
|
||
}
|
||
|
||
ss_suspended = 0;
|
||
|
||
if (handler == SIG_IGN)
|
||
/* Ignore the signal altogether. */
|
||
act = ignore;
|
||
else if (handler != SIG_ERR)
|
||
{
|
||
/* Run the preemption-provided handler. */
|
||
action = &preempt_sigaction;
|
||
act = handle;
|
||
}
|
||
else
|
||
{
|
||
/* No preemption. Do normal handling. */
|
||
|
||
action = & _hurd_sigstate_actions (ss) [signo];
|
||
|
||
if (!untraced && __sigismember (&_hurdsig_traced, signo))
|
||
{
|
||
/* We are being traced. Stop to tell the debugger of the signal. */
|
||
if (_hurd_stopped)
|
||
/* Already stopped. Mark the signal as pending;
|
||
when resumed, we will notice it and stop again. */
|
||
mark_pending ();
|
||
else
|
||
suspend ();
|
||
_hurd_sigstate_unlock (ss);
|
||
reply ();
|
||
return NULL;
|
||
}
|
||
|
||
handler = action->sa_handler;
|
||
|
||
if (handler == SIG_DFL)
|
||
/* Figure out the default action for this signal. */
|
||
switch (signo)
|
||
{
|
||
case 0:
|
||
/* A sig_post msg with SIGNO==0 is sent to
|
||
tell us to check for pending signals. */
|
||
act = ignore;
|
||
break;
|
||
|
||
case SIGTTIN:
|
||
case SIGTTOU:
|
||
case SIGSTOP:
|
||
case SIGTSTP:
|
||
act = stop;
|
||
break;
|
||
|
||
case SIGCONT:
|
||
case SIGIO:
|
||
case SIGURG:
|
||
case SIGCHLD:
|
||
case SIGWINCH:
|
||
act = ignore;
|
||
break;
|
||
|
||
case SIGQUIT:
|
||
case SIGILL:
|
||
case SIGTRAP:
|
||
case SIGIOT:
|
||
case SIGEMT:
|
||
case SIGFPE:
|
||
case SIGBUS:
|
||
case SIGSEGV:
|
||
case SIGSYS:
|
||
act = core;
|
||
break;
|
||
|
||
case SIGINFO:
|
||
if (_hurd_pgrp == _hurd_pid)
|
||
{
|
||
/* We are the process group leader. Since there is no
|
||
user-specified handler for SIGINFO, we use a default one
|
||
which prints something interesting. We use the normal
|
||
handler mechanism instead of just doing it here to avoid
|
||
the signal thread faulting or blocking in this
|
||
potentially hairy operation. */
|
||
act = handle;
|
||
handler = _hurd_siginfo_handler;
|
||
}
|
||
else
|
||
act = ignore;
|
||
break;
|
||
|
||
default:
|
||
act = term;
|
||
break;
|
||
}
|
||
else if (handler == SIG_IGN)
|
||
act = ignore;
|
||
else
|
||
act = handle;
|
||
|
||
if (__sigmask (signo) & STOPSIGS)
|
||
/* Stop signals clear a pending SIGCONT even if they
|
||
are handled or ignored (but not if preempted). */
|
||
__sigdelset (&ss->pending, SIGCONT);
|
||
else
|
||
{
|
||
if (signo == SIGCONT)
|
||
/* Even if handled or ignored (but not preempted), SIGCONT clears
|
||
stop signals and resumes the process. */
|
||
ss->pending &= ~STOPSIGS;
|
||
|
||
if (_hurd_stopped && act != stop && (untraced || signo == SIGCONT))
|
||
resume ();
|
||
}
|
||
}
|
||
|
||
if (_hurd_orphaned && act == stop
|
||
&& (__sigmask (signo) & (__sigmask (SIGTTIN) | __sigmask (SIGTTOU)
|
||
| __sigmask (SIGTSTP))))
|
||
{
|
||
/* If we would ordinarily stop for a job control signal, but we are
|
||
orphaned so noone would ever notice and continue us again, we just
|
||
quietly die, alone and in the dark. */
|
||
detail->code = signo;
|
||
signo = SIGKILL;
|
||
act = term;
|
||
}
|
||
|
||
/* Handle receipt of a blocked signal, or any signal while stopped. */
|
||
if (__sigismember (&blocked, signo) || (signo != SIGKILL && _hurd_stopped))
|
||
{
|
||
mark_pending ();
|
||
act = ignore;
|
||
}
|
||
|
||
/* Perform the chosen action for the signal. */
|
||
switch (act)
|
||
{
|
||
case stop:
|
||
if (_hurd_stopped)
|
||
{
|
||
/* We are already stopped, but receiving an untraced stop
|
||
signal. Instead of resuming and suspending again, just
|
||
notify the proc server of the new stop signal. */
|
||
error_t err = __USEPORT (PROC, __proc_mark_stop
|
||
(port, signo, detail->code));
|
||
assert_perror (err);
|
||
}
|
||
else
|
||
/* Suspend the process. */
|
||
suspend ();
|
||
break;
|
||
|
||
case ignore:
|
||
if (detail->exc)
|
||
/* Blocking or ignoring a machine exception is fatal.
|
||
Otherwise we could just spin on the faulting instruction. */
|
||
goto fatal;
|
||
|
||
/* Nobody cares about this signal. If there was a call to resume
|
||
above in SIGCONT processing and we've left a thread suspended,
|
||
now's the time to set it going. */
|
||
if (ss_suspended)
|
||
{
|
||
assert (ss->thread != MACH_PORT_NULL);
|
||
err = __thread_resume (ss->thread);
|
||
assert_perror (err);
|
||
ss_suspended = 0;
|
||
}
|
||
break;
|
||
|
||
sigbomb:
|
||
/* We got a fault setting up the stack frame for the handler.
|
||
Nothing to do but die; BSD gets SIGILL in this case. */
|
||
detail->code = signo; /* XXX ? */
|
||
signo = SIGILL;
|
||
|
||
fatal:
|
||
act = core;
|
||
/* FALLTHROUGH */
|
||
|
||
case term: /* Time to die. */
|
||
case core: /* And leave a rotting corpse. */
|
||
/* Have the proc server stop all other threads in our task. */
|
||
err = __USEPORT (PROC, __proc_dostop (port, _hurd_msgport_thread));
|
||
assert_perror (err);
|
||
/* No more user instructions will be executed.
|
||
The signal can now be considered delivered. */
|
||
reply ();
|
||
/* Abort all server operations now in progress. */
|
||
abort_all_rpcs (signo, &thread_state, 0);
|
||
|
||
{
|
||
int status = W_EXITCODE (0, signo);
|
||
/* Do a core dump if desired. Only set the wait status bit saying we
|
||
in fact dumped core if the operation was actually successful. */
|
||
if (act == core && write_corefile (signo, detail))
|
||
status |= WCOREFLAG;
|
||
/* Tell proc how we died and then stick the saber in the gut. */
|
||
_hurd_exit (status);
|
||
/* NOTREACHED */
|
||
}
|
||
|
||
case handle:
|
||
/* Call a handler for this signal. */
|
||
{
|
||
struct sigcontext *scp, ocontext;
|
||
int wait_for_reply, state_changed;
|
||
|
||
assert (ss->thread != MACH_PORT_NULL);
|
||
|
||
/* Stop the thread and abort its pending RPC operations. */
|
||
if (! ss_suspended)
|
||
{
|
||
err = __thread_suspend (ss->thread);
|
||
assert_perror (err);
|
||
}
|
||
|
||
/* Abort the thread's kernel context, so any pending message send
|
||
or receive completes immediately or aborts. If an interruptible
|
||
RPC is in progress, abort_rpcs will do this. But we must always
|
||
do it before fetching the thread's state, because
|
||
thread_get_state is never kosher before thread_abort. */
|
||
abort_thread (ss, &thread_state, NULL);
|
||
|
||
if (ss->context)
|
||
{
|
||
/* We have a previous sigcontext that sigreturn was about
|
||
to restore when another signal arrived. */
|
||
|
||
mach_port_t *loc;
|
||
|
||
if (_hurdsig_catch_memory_fault (ss->context))
|
||
{
|
||
/* We faulted reading the thread's stack. Forget that
|
||
context and pretend it wasn't there. It almost
|
||
certainly crash if this handler returns, but that's it's
|
||
problem. */
|
||
ss->context = NULL;
|
||
}
|
||
else
|
||
{
|
||
/* Copy the context from the thread's stack before
|
||
we start diddling the stack to set up the handler. */
|
||
ocontext = *ss->context;
|
||
ss->context = &ocontext;
|
||
}
|
||
_hurdsig_end_catch_fault ();
|
||
|
||
if (! machine_get_basic_state (ss->thread, &thread_state))
|
||
goto sigbomb;
|
||
loc = interrupted_reply_port_location (ss->thread,
|
||
&thread_state, 1);
|
||
if (loc && *loc != MACH_PORT_NULL)
|
||
/* This is the reply port for the context which called
|
||
sigreturn. Since we are abandoning that context entirely
|
||
and restoring SS->context instead, destroy this port. */
|
||
__mach_port_destroy (__mach_task_self (), *loc);
|
||
|
||
/* The thread was in sigreturn, not in any interruptible RPC. */
|
||
wait_for_reply = 0;
|
||
|
||
assert (! __spin_lock_locked (&ss->critical_section_lock));
|
||
}
|
||
else
|
||
{
|
||
int crit = __spin_lock_locked (&ss->critical_section_lock);
|
||
|
||
wait_for_reply
|
||
= (_hurdsig_abort_rpcs (ss,
|
||
/* In a critical section, any RPC
|
||
should be cancelled instead of
|
||
restarted, regardless of
|
||
SA_RESTART, so the entire
|
||
"atomic" operation can be aborted
|
||
as a unit. */
|
||
crit ? 0 : signo, 1,
|
||
&thread_state, &state_changed,
|
||
reply)
|
||
!= MACH_PORT_NULL);
|
||
|
||
if (crit)
|
||
{
|
||
/* The thread is in a critical section. Mark the signal as
|
||
pending. When it finishes the critical section, it will
|
||
check for pending signals. */
|
||
mark_pending ();
|
||
if (state_changed)
|
||
/* Some cases of interrupting an RPC must change the
|
||
thread state to back out the call. Normally this
|
||
change is rolled into the warping to the handler and
|
||
sigreturn, but we are not running the handler now
|
||
because the thread is in a critical section. Instead,
|
||
mutate the thread right away for the RPC interruption
|
||
and resume it; the RPC will return early so the
|
||
critical section can end soon. */
|
||
__thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR,
|
||
(natural_t *) &thread_state.basic,
|
||
MACHINE_THREAD_STATE_COUNT);
|
||
/* */
|
||
ss->intr_port = MACH_PORT_NULL;
|
||
__thread_resume (ss->thread);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Call the machine-dependent function to set the thread up
|
||
to run the signal handler, and preserve its old context. */
|
||
scp = _hurd_setup_sighandler (ss, action, handler, signo, detail,
|
||
wait_for_reply, &thread_state);
|
||
if (scp == NULL)
|
||
goto sigbomb;
|
||
|
||
/* Set the machine-independent parts of the signal context. */
|
||
|
||
{
|
||
/* Fetch the thread variable for the MiG reply port,
|
||
and set it to MACH_PORT_NULL. */
|
||
mach_port_t *loc = interrupted_reply_port_location (ss->thread,
|
||
&thread_state,
|
||
1);
|
||
if (loc)
|
||
{
|
||
scp->sc_reply_port = *loc;
|
||
*loc = MACH_PORT_NULL;
|
||
}
|
||
else
|
||
scp->sc_reply_port = MACH_PORT_NULL;
|
||
|
||
/* Save the intr_port in use by the interrupted code,
|
||
and clear the cell before running the trampoline. */
|
||
scp->sc_intr_port = ss->intr_port;
|
||
ss->intr_port = MACH_PORT_NULL;
|
||
|
||
if (ss->context)
|
||
{
|
||
/* After the handler runs we will restore to the state in
|
||
SS->context, not the state of the thread now. So restore
|
||
that context's reply port and intr port. */
|
||
|
||
scp->sc_reply_port = ss->context->sc_reply_port;
|
||
scp->sc_intr_port = ss->context->sc_intr_port;
|
||
|
||
ss->context = NULL;
|
||
}
|
||
}
|
||
|
||
/* Backdoor extra argument to signal handler. */
|
||
scp->sc_error = detail->error;
|
||
|
||
/* Block requested signals while running the handler. */
|
||
scp->sc_mask = ss->blocked;
|
||
__sigorset (&ss->blocked, &ss->blocked, &action->sa_mask);
|
||
|
||
/* Also block SIGNO unless we're asked not to. */
|
||
if (! (action->sa_flags & (SA_RESETHAND | SA_NODEFER)))
|
||
__sigaddset (&ss->blocked, signo);
|
||
|
||
/* Reset to SIG_DFL if requested. SIGILL and SIGTRAP cannot
|
||
be automatically reset when delivered; the system silently
|
||
enforces this restriction. */
|
||
if (action->sa_flags & SA_RESETHAND
|
||
&& signo != SIGILL && signo != SIGTRAP)
|
||
action->sa_handler = SIG_DFL;
|
||
|
||
/* Any sigsuspend call must return after the handler does. */
|
||
wake_sigsuspend (ss);
|
||
|
||
/* Start the thread running the handler (or possibly waiting for an
|
||
RPC reply before running the handler). */
|
||
err = __thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR,
|
||
(natural_t *) &thread_state.basic,
|
||
MACHINE_THREAD_STATE_COUNT);
|
||
assert_perror (err);
|
||
err = __thread_resume (ss->thread);
|
||
assert_perror (err);
|
||
thread_state.set = 0; /* Everything we know is now wrong. */
|
||
break;
|
||
}
|
||
}
|
||
|
||
return ss;
|
||
}
|
||
|
||
/* Return the set of pending signals in SS which should be delivered. */
|
||
static sigset_t
|
||
pending_signals (struct hurd_sigstate *ss)
|
||
{
|
||
/* We don't worry about any pending signals if we are stopped, nor if
|
||
SS is in a critical section. We are guaranteed to get a sig_post
|
||
message before any of them become deliverable: either the SIGCONT
|
||
signal, or a sig_post with SIGNO==0 as an explicit poll when the
|
||
thread finishes its critical section. */
|
||
if (_hurd_stopped || __spin_lock_locked (&ss->critical_section_lock))
|
||
return 0;
|
||
|
||
return _hurd_sigstate_pending (ss) & ~ss->blocked;
|
||
}
|
||
|
||
/* Post the specified pending signals in SS and return 1. If one of
|
||
them is traced, abort immediately and return 0. SS must be locked on
|
||
entry and will be unlocked in all cases. */
|
||
static int
|
||
post_pending (struct hurd_sigstate *ss, sigset_t pending, void (*reply) (void))
|
||
{
|
||
int signo;
|
||
struct hurd_signal_detail detail;
|
||
|
||
/* Make sure SS corresponds to an actual thread, since we assume it won't
|
||
change in post_signal. */
|
||
assert (ss->thread != MACH_PORT_NULL);
|
||
|
||
for (signo = 1; signo < NSIG; ++signo)
|
||
if (__sigismember (&pending, signo))
|
||
{
|
||
detail = sigstate_clear_pending (ss, signo);
|
||
_hurd_sigstate_unlock (ss);
|
||
|
||
/* Will reacquire the lock, except if the signal is traced. */
|
||
if (! post_signal (ss, signo, &detail, 0, reply))
|
||
return 0;
|
||
}
|
||
|
||
/* No more signals pending; SS->lock is still locked. */
|
||
_hurd_sigstate_unlock (ss);
|
||
|
||
return 1;
|
||
}
|
||
|
||
/* Post all the pending signals of all threads and return 1. If a traced
|
||
signal is encountered, abort immediately and return 0. */
|
||
static int
|
||
post_all_pending_signals (void (*reply) (void))
|
||
{
|
||
struct hurd_sigstate *ss;
|
||
sigset_t pending = 0;
|
||
|
||
for (;;)
|
||
{
|
||
__mutex_lock (&_hurd_siglock);
|
||
for (ss = _hurd_sigstates; ss != NULL; ss = ss->next)
|
||
{
|
||
_hurd_sigstate_lock (ss);
|
||
|
||
pending = pending_signals (ss);
|
||
if (pending)
|
||
/* post_pending() below will unlock SS. */
|
||
break;
|
||
|
||
_hurd_sigstate_unlock (ss);
|
||
}
|
||
__mutex_unlock (&_hurd_siglock);
|
||
|
||
if (! pending)
|
||
return 1;
|
||
if (! post_pending (ss, pending, reply))
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/* Deliver a signal. SS is not locked. */
|
||
void
|
||
_hurd_internal_post_signal (struct hurd_sigstate *ss,
|
||
int signo, struct hurd_signal_detail *detail,
|
||
mach_port_t reply_port,
|
||
mach_msg_type_name_t reply_port_type,
|
||
int untraced)
|
||
{
|
||
/* Reply to this sig_post message. */
|
||
__typeof (__msg_sig_post_reply) *reply_rpc
|
||
= (untraced ? __msg_sig_post_untraced_reply : __msg_sig_post_reply);
|
||
void reply (void)
|
||
{
|
||
error_t err;
|
||
if (reply_port == MACH_PORT_NULL)
|
||
return;
|
||
err = (*reply_rpc) (reply_port, reply_port_type, 0);
|
||
reply_port = MACH_PORT_NULL;
|
||
if (err != MACH_SEND_INVALID_DEST) /* Ignore dead reply port. */
|
||
assert_perror (err);
|
||
}
|
||
|
||
ss = post_signal (ss, signo, detail, untraced, reply);
|
||
if (! ss)
|
||
return;
|
||
|
||
/* The signal was neither fatal nor traced. We still hold SS->lock. */
|
||
if (signo != 0 && ss->thread != MACH_PORT_NULL)
|
||
{
|
||
/* The signal has either been ignored or is now being handled. We can
|
||
consider it delivered and reply to the killer. */
|
||
reply ();
|
||
|
||
/* Post any pending signals for this thread. */
|
||
if (! post_pending (ss, pending_signals (ss), reply))
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* If this was a process-wide signal or a poll request, we need
|
||
to check for pending signals for all threads. */
|
||
_hurd_sigstate_unlock (ss);
|
||
if (! post_all_pending_signals (reply))
|
||
return;
|
||
|
||
/* All pending signals delivered to all threads.
|
||
Now we can send the reply message even for signal 0. */
|
||
reply ();
|
||
}
|
||
}
|
||
|
||
/* Decide whether REFPORT enables the sender to send us a SIGNO signal.
|
||
Returns zero if so, otherwise the error code to return to the sender. */
|
||
|
||
static error_t
|
||
signal_allowed (int signo, mach_port_t refport)
|
||
{
|
||
if (signo < 0 || signo >= NSIG)
|
||
return EINVAL;
|
||
|
||
if (refport == __mach_task_self ())
|
||
/* Can send any signal. */
|
||
goto win;
|
||
|
||
/* Avoid needing to check for this below. */
|
||
if (refport == MACH_PORT_NULL)
|
||
return EPERM;
|
||
|
||
switch (signo)
|
||
{
|
||
case SIGINT:
|
||
case SIGQUIT:
|
||
case SIGTSTP:
|
||
case SIGHUP:
|
||
case SIGINFO:
|
||
case SIGTTIN:
|
||
case SIGTTOU:
|
||
case SIGWINCH:
|
||
/* Job control signals can be sent by the controlling terminal. */
|
||
if (__USEPORT (CTTYID, port == refport))
|
||
goto win;
|
||
break;
|
||
|
||
case SIGCONT:
|
||
{
|
||
/* A continue signal can be sent by anyone in the session. */
|
||
mach_port_t sessport;
|
||
if (! __USEPORT (PROC, __proc_getsidport (port, &sessport)))
|
||
{
|
||
__mach_port_deallocate (__mach_task_self (), sessport);
|
||
if (refport == sessport)
|
||
goto win;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case SIGIO:
|
||
case SIGURG:
|
||
{
|
||
/* Any io object a file descriptor refers to might send us
|
||
one of these signals using its async ID port for REFPORT.
|
||
|
||
This is pretty wide open; it is not unlikely that some random
|
||
process can at least open for reading something we have open,
|
||
get its async ID port, and send us a spurious SIGIO or SIGURG
|
||
signal. But BSD is actually wider open than that!--you can set
|
||
the owner of an io object to any process or process group
|
||
whatsoever and send them gratuitous signals.
|
||
|
||
Someday we could implement some reasonable scheme for
|
||
authorizing SIGIO and SIGURG signals properly. */
|
||
|
||
int d;
|
||
int lucky = 0; /* True if we find a match for REFPORT. */
|
||
__mutex_lock (&_hurd_dtable_lock);
|
||
for (d = 0; !lucky && (unsigned) d < (unsigned) _hurd_dtablesize; ++d)
|
||
{
|
||
struct hurd_userlink ulink;
|
||
io_t port;
|
||
mach_port_t asyncid;
|
||
if (_hurd_dtable[d] == NULL)
|
||
continue;
|
||
port = _hurd_port_get (&_hurd_dtable[d]->port, &ulink);
|
||
if (! __io_get_icky_async_id (port, &asyncid))
|
||
{
|
||
if (refport == asyncid)
|
||
/* Break out of the loop on the next iteration. */
|
||
lucky = 1;
|
||
__mach_port_deallocate (__mach_task_self (), asyncid);
|
||
}
|
||
_hurd_port_free (&_hurd_dtable[d]->port, &ulink, port);
|
||
}
|
||
__mutex_unlock (&_hurd_dtable_lock);
|
||
/* If we found a lucky winner, we've set D to -1 in the loop. */
|
||
if (lucky)
|
||
goto win;
|
||
}
|
||
}
|
||
|
||
/* If this signal is legit, we have done `goto win' by now.
|
||
When we return the error, mig deallocates REFPORT. */
|
||
return EPERM;
|
||
|
||
win:
|
||
/* Deallocate the REFPORT send right; we are done with it. */
|
||
__mach_port_deallocate (__mach_task_self (), refport);
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Implement the sig_post RPC from <hurd/msg.defs>;
|
||
sent when someone wants us to get a signal. */
|
||
kern_return_t
|
||
_S_msg_sig_post (mach_port_t me,
|
||
mach_port_t reply_port, mach_msg_type_name_t reply_port_type,
|
||
int signo, natural_t sigcode,
|
||
mach_port_t refport)
|
||
{
|
||
error_t err;
|
||
struct hurd_signal_detail d;
|
||
|
||
if (err = signal_allowed (signo, refport))
|
||
return err;
|
||
|
||
d.code = d.exc_subcode = sigcode;
|
||
d.exc = 0;
|
||
|
||
/* Post the signal to a global receiver thread (or mark it pending in
|
||
the global sigstate). This will reply when the signal can be
|
||
considered delivered. */
|
||
_hurd_internal_post_signal (_hurd_global_sigstate,
|
||
signo, &d, reply_port, reply_port_type,
|
||
0); /* Stop if traced. */
|
||
|
||
return MIG_NO_REPLY; /* Already replied. */
|
||
}
|
||
|
||
/* Implement the sig_post_untraced RPC from <hurd/msg.defs>;
|
||
sent when the debugger wants us to really get a signal
|
||
even if we are traced. */
|
||
kern_return_t
|
||
_S_msg_sig_post_untraced (mach_port_t me,
|
||
mach_port_t reply_port,
|
||
mach_msg_type_name_t reply_port_type,
|
||
int signo, natural_t sigcode,
|
||
mach_port_t refport)
|
||
{
|
||
error_t err;
|
||
struct hurd_signal_detail d;
|
||
|
||
if (err = signal_allowed (signo, refport))
|
||
return err;
|
||
|
||
d.code = d.exc_subcode = sigcode;
|
||
d.exc = 0;
|
||
|
||
/* Post the signal to the designated signal-receiving thread. This will
|
||
reply when the signal can be considered delivered. */
|
||
_hurd_internal_post_signal (_hurd_global_sigstate,
|
||
signo, &d, reply_port, reply_port_type,
|
||
1); /* Untraced flag. */
|
||
|
||
return MIG_NO_REPLY; /* Already replied. */
|
||
}
|
||
|
||
extern void __mig_init (void *);
|
||
|
||
#include <mach/task_special_ports.h>
|
||
|
||
/* Initialize the message port, _hurd_global_sigstate, and start the
|
||
signal thread. */
|
||
|
||
void
|
||
_hurdsig_init (const int *intarray, size_t intarraysize)
|
||
{
|
||
error_t err;
|
||
vm_size_t stacksize;
|
||
struct hurd_sigstate *ss;
|
||
|
||
__mutex_init (&_hurd_siglock);
|
||
|
||
err = __mach_port_allocate (__mach_task_self (),
|
||
MACH_PORT_RIGHT_RECEIVE,
|
||
&_hurd_msgport);
|
||
assert_perror (err);
|
||
|
||
/* Make a send right to the signal port. */
|
||
err = __mach_port_insert_right (__mach_task_self (),
|
||
_hurd_msgport,
|
||
_hurd_msgport,
|
||
MACH_MSG_TYPE_MAKE_SEND);
|
||
assert_perror (err);
|
||
|
||
/* Initialize the global signal state. */
|
||
_hurd_global_sigstate = _hurd_thread_sigstate (MACH_PORT_NULL);
|
||
|
||
/* We block all signals, and let actual threads pull them from the
|
||
pending mask. */
|
||
__sigfillset(& _hurd_global_sigstate->blocked);
|
||
|
||
/* Initialize the main thread's signal state. */
|
||
ss = _hurd_self_sigstate ();
|
||
|
||
/* Mark it as a process-wide signal receiver. Threads in this set use
|
||
the common action vector in _hurd_global_sigstate. */
|
||
_hurd_sigstate_set_global_rcv (ss);
|
||
|
||
/* Copy inherited signal settings from our parent (or pre-exec process
|
||
state) */
|
||
if (intarraysize > INIT_SIGMASK)
|
||
ss->blocked = intarray[INIT_SIGMASK];
|
||
if (intarraysize > INIT_SIGPENDING)
|
||
_hurd_global_sigstate->pending = intarray[INIT_SIGPENDING];
|
||
if (intarraysize > INIT_SIGIGN && intarray[INIT_SIGIGN] != 0)
|
||
{
|
||
int signo;
|
||
for (signo = 1; signo < NSIG; ++signo)
|
||
if (intarray[INIT_SIGIGN] & __sigmask(signo))
|
||
_hurd_global_sigstate->actions[signo].sa_handler = SIG_IGN;
|
||
}
|
||
|
||
/* Start the signal thread listening on the message port. */
|
||
|
||
#pragma weak __pthread_create
|
||
if (!__pthread_create)
|
||
{
|
||
err = __thread_create (__mach_task_self (), &_hurd_msgport_thread);
|
||
assert_perror (err);
|
||
|
||
stacksize = __vm_page_size * 8; /* Small stack for signal thread. */
|
||
err = __mach_setup_thread (__mach_task_self (), _hurd_msgport_thread,
|
||
_hurd_msgport_receive,
|
||
(vm_address_t *) &__hurd_sigthread_stack_base,
|
||
&stacksize);
|
||
assert_perror (err);
|
||
err = __mach_setup_tls (_hurd_msgport_thread);
|
||
assert_perror (err);
|
||
|
||
__hurd_sigthread_stack_end = __hurd_sigthread_stack_base + stacksize;
|
||
|
||
/* Reinitialize the MiG support routines so they will use a per-thread
|
||
variable for the cached reply port. */
|
||
__mig_init ((void *) __hurd_sigthread_stack_base);
|
||
|
||
err = __thread_resume (_hurd_msgport_thread);
|
||
assert_perror (err);
|
||
}
|
||
else
|
||
{
|
||
pthread_t thread;
|
||
pthread_attr_t attr;
|
||
void *addr;
|
||
size_t size;
|
||
|
||
/* When pthread is being used, we need to make the signal thread a
|
||
proper pthread. Otherwise it cannot use mutex_lock et al, which
|
||
will be the pthread versions. Various of the message port RPC
|
||
handlers need to take locks, so we need to be able to call into
|
||
pthread code and meet its assumptions about how our thread and
|
||
its stack are arranged. Since pthread puts it there anyway,
|
||
we'll let the signal thread's per-thread variables be found as for
|
||
any normal pthread, and just leave the magic __hurd_sigthread_*
|
||
values all zero so they'll be ignored. */
|
||
|
||
#pragma weak __pthread_detach
|
||
#pragma weak __pthread_getattr_np
|
||
#pragma weak __pthread_attr_getstack
|
||
__pthread_create(&thread, NULL, &_hurd_msgport_receive, NULL);
|
||
|
||
/* Record signal thread stack layout for fork() */
|
||
__pthread_getattr_np (thread, &attr);
|
||
__pthread_attr_getstack (&attr, &addr, &size);
|
||
__hurd_sigthread_stack_base = (uintptr_t) addr;
|
||
__hurd_sigthread_stack_end = __hurd_sigthread_stack_base + size;
|
||
|
||
__pthread_detach(thread);
|
||
|
||
/* XXX We need the thread port for the signal thread further on
|
||
in this thread (see hurdfault.c:_hurdsigfault_init).
|
||
Therefore we block until _hurd_msgport_thread is initialized
|
||
by the newly created thread. This really shouldn't be
|
||
necessary; we should be able to fetch the thread port for a
|
||
pthread from here. */
|
||
while (_hurd_msgport_thread == 0)
|
||
__swtch_pri (0);
|
||
}
|
||
|
||
/* Receive exceptions on the signal port. */
|
||
#ifdef TASK_EXCEPTION_PORT
|
||
__task_set_special_port (__mach_task_self (),
|
||
TASK_EXCEPTION_PORT, _hurd_msgport);
|
||
#elif defined (EXC_MASK_ALL)
|
||
__task_set_exception_ports (__mach_task_self (),
|
||
EXC_MASK_ALL & ~(EXC_MASK_SYSCALL
|
||
| EXC_MASK_MACH_SYSCALL
|
||
| EXC_MASK_RPC_ALERT),
|
||
_hurd_msgport,
|
||
EXCEPTION_DEFAULT, MACHINE_THREAD_STATE);
|
||
#else
|
||
# error task_set_exception_port?
|
||
#endif
|
||
|
||
/* Sanity check. Any pending, unblocked signals should have been
|
||
taken by our predecessor incarnation (i.e. parent or pre-exec state)
|
||
before packing up our init ints. This assert is last (not above)
|
||
so that signal handling is all set up to handle the abort. */
|
||
assert ((ss->pending &~ ss->blocked) == 0);
|
||
}
|
||
/* XXXX */
|
||
/* Reauthenticate with the proc server. */
|
||
|
||
static void
|
||
reauth_proc (mach_port_t new)
|
||
{
|
||
mach_port_t ref, ignore;
|
||
|
||
ref = __mach_reply_port ();
|
||
if (! HURD_PORT_USE (&_hurd_ports[INIT_PORT_PROC],
|
||
__proc_reauthenticate (port, ref,
|
||
MACH_MSG_TYPE_MAKE_SEND)
|
||
|| __auth_user_authenticate (new, ref,
|
||
MACH_MSG_TYPE_MAKE_SEND,
|
||
&ignore))
|
||
&& ignore != MACH_PORT_NULL)
|
||
__mach_port_deallocate (__mach_task_self (), ignore);
|
||
__mach_port_destroy (__mach_task_self (), ref);
|
||
|
||
/* Set the owner of the process here too. */
|
||
__mutex_lock (&_hurd_id.lock);
|
||
if (!_hurd_check_ids ())
|
||
HURD_PORT_USE (&_hurd_ports[INIT_PORT_PROC],
|
||
__proc_setowner (port,
|
||
(_hurd_id.gen.nuids
|
||
? _hurd_id.gen.uids[0] : 0),
|
||
!_hurd_id.gen.nuids));
|
||
__mutex_unlock (&_hurd_id.lock);
|
||
|
||
(void) &reauth_proc; /* Silence compiler warning. */
|
||
}
|
||
text_set_element (_hurd_reauth_hook, reauth_proc);
|
||
|
||
/* Like `getenv', but safe for the signal thread to run.
|
||
If the environment is trashed, this will just return NULL. */
|
||
|
||
const char *
|
||
_hurdsig_getenv (const char *variable)
|
||
{
|
||
if (__libc_enable_secure)
|
||
return NULL;
|
||
|
||
if (_hurdsig_catch_memory_fault (__environ))
|
||
/* We bombed in getenv. */
|
||
return NULL;
|
||
else
|
||
{
|
||
const size_t len = strlen (variable);
|
||
char *value = NULL;
|
||
char *volatile *ep = __environ;
|
||
while (*ep)
|
||
{
|
||
const char *p = *ep;
|
||
_hurdsig_fault_preemptor.first = (long int) p;
|
||
_hurdsig_fault_preemptor.last = VM_MAX_ADDRESS;
|
||
if (! strncmp (p, variable, len) && p[len] == '=')
|
||
{
|
||
size_t valuelen;
|
||
p += len + 1;
|
||
valuelen = strlen (p);
|
||
_hurdsig_fault_preemptor.last = (long int) (p + valuelen);
|
||
value = malloc (++valuelen);
|
||
if (value)
|
||
memcpy (value, p, valuelen);
|
||
break;
|
||
}
|
||
_hurdsig_fault_preemptor.first = (long int) ++ep;
|
||
_hurdsig_fault_preemptor.last = (long int) (ep + 1);
|
||
}
|
||
_hurdsig_end_catch_fault ();
|
||
return value;
|
||
}
|
||
}
|