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d1436edcb9
* include/unistd.h: Add libc_hidden_proto for __fork and __vfork. * sysdeps/generic/fork.c: Add libc_hidden_def for __fork. * sysdeps/mach/hurd/fork.c: Likewise. * sysdeps/unix/sysv/aix/fork.c: Likewise. * sysdeps/unix/fork.S: Add __GI___fork alias. * sysdeps/unix/arm/fork.S: Likewise. * sysdeps/unix/bsd/osf/alpha/fork.S: Likewise. * sysdeps/unix/i386/fork.S: Likewise. * sysdeps/unix/mips/fork.S: Likewise. * sysdeps/unix/sparc/fork.S: Likewise. * sysdeps/unix/sysv/linux/ia64/fork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/fork.S: Likewise. * sysdeps/unix/sysv/linux/syscalls.list: Likewise. * sysdeps/generic/vfork.c: Add libc_hidden_def for __vfork. * sysdeps/unix/bsd/hp/m68k/vfork.S: Add __GI___vfork alias. * sysdeps/unix/bsd/i386/vfork.S: Likewise. * sysdeps/unix/bsd/sun/m68k/vfork.S: Likewise. * sysdeps/unix/bsd/ultrix4/mips/vfork.S: Likewise. * sysdeps/unix/bsd/vax/vfork.S: Likewise. * sysdeps/unix/sparc/vfork.S: Likewise. * sysdeps/unix/sysv/linux/arm/vfork.S: Likewise. * sysdeps/unix/sysv/linux/cris/vfork.S: Likewise. * sysdeps/unix/sysv/linux/i386/vfork.S: Likewise. * sysdeps/unix/sysv/linux/ia64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/m68k/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sh/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/vfork.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/vfork.S: Likewise.
698 lines
23 KiB
C
698 lines
23 KiB
C
/* Copyright (C) 1994,95,96,97,99,2001,02 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, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <errno.h>
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#include <unistd.h>
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#include <hurd.h>
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#include <hurd/signal.h>
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#include <setjmp.h>
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#include "thread_state.h"
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#include <sysdep.h> /* For stack growth direction. */
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#include "set-hooks.h"
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#include <assert.h>
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#include "hurdmalloc.h" /* XXX */
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#undef __fork
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/* Things that want to be locked while forking. */
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symbol_set_declare (_hurd_fork_locks)
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/* Things that want to be called before we fork, to prepare the parent for
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task_create, when the new child task will inherit our address space. */
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DEFINE_HOOK (_hurd_fork_prepare_hook, (void));
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/* Things that want to be called when we are forking, with the above all
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locked. They are passed the task port of the child. The child process
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is all set up except for doing proc_child, and has no threads yet. */
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DEFINE_HOOK (_hurd_fork_setup_hook, (void));
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/* Things to be run in the child fork. */
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DEFINE_HOOK (_hurd_fork_child_hook, (void));
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/* Things to be run in the parent fork. */
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DEFINE_HOOK (_hurd_fork_parent_hook, (void));
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/* Clone the calling process, creating an exact copy.
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Return -1 for errors, 0 to the new process,
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and the process ID of the new process to the old process. */
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pid_t
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__fork (void)
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{
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jmp_buf env;
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pid_t pid;
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size_t i;
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error_t err;
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struct hurd_sigstate *volatile ss;
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ss = _hurd_self_sigstate ();
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__spin_lock (&ss->critical_section_lock);
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#undef LOSE
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#define LOSE do { assert_perror (err); goto lose; } while (0) /* XXX */
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if (! setjmp (env))
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{
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process_t newproc;
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task_t newtask;
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thread_t thread, sigthread;
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mach_port_urefs_t thread_refs, sigthread_refs;
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struct machine_thread_state state;
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mach_msg_type_number_t statecount;
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mach_port_t *portnames = NULL;
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mach_msg_type_number_t nportnames = 0;
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mach_port_type_t *porttypes = NULL;
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mach_msg_type_number_t nporttypes = 0;
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thread_t *threads = NULL;
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mach_msg_type_number_t nthreads = 0;
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int ports_locked = 0, stopped = 0;
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void resume_threads (void)
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{
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if (! stopped)
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return;
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assert (threads);
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for (i = 0; i < nthreads; ++i)
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if (threads[i] != ss->thread)
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__thread_resume (threads[i]);
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stopped = 0;
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}
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/* Run things that prepare for forking before we create the task. */
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RUN_HOOK (_hurd_fork_prepare_hook, ());
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/* Lock things that want to be locked before we fork. */
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{
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void *const *p;
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for (p = symbol_set_first_element (_hurd_fork_locks);
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! symbol_set_end_p (_hurd_fork_locks, p);
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++p)
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__mutex_lock (*p);
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}
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__mutex_lock (&_hurd_siglock);
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newtask = MACH_PORT_NULL;
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thread = sigthread = MACH_PORT_NULL;
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newproc = MACH_PORT_NULL;
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/* Lock all the port cells for the standard ports while we copy the
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address space. We want to insert all the send rights into the
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child with the same names. */
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for (i = 0; i < _hurd_nports; ++i)
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__spin_lock (&_hurd_ports[i].lock);
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ports_locked = 1;
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/* Stop all other threads while copying the address space,
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so nothing changes. */
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err = __proc_dostop (_hurd_ports[INIT_PORT_PROC].port, ss->thread);
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if (!err)
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{
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stopped = 1;
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#define XXX_KERNEL_PAGE_FAULT_BUG /* XXX work around page fault bug in mk */
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#ifdef XXX_KERNEL_PAGE_FAULT_BUG
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/* Gag me with a pitchfork.
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The bug scenario is this:
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- The page containing __mach_task_self_ is paged out.
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- The signal thread was faulting on that page when we
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suspended it via proc_dostop. It holds some lock, or set
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some busy bit, or somesuch.
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- Now this thread faults on that same page.
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- GRATUIOUS DEADLOCK
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We can break the deadlock by aborting the thread that faulted
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first, which if the bug happened was the signal thread because
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it is the only other thread and we just suspended it.
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*/
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__thread_abort (_hurd_msgport_thread);
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#endif
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/* Create the child task. It will inherit a copy of our memory. */
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err = __task_create (__mach_task_self (),
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#ifdef KERN_INVALID_LEDGER
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NULL, 0, /* OSF Mach */
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#endif
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1, &newtask);
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}
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/* Unlock the global signal state lock, so we do not
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block the signal thread any longer than necessary. */
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__mutex_unlock (&_hurd_siglock);
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if (err)
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LOSE;
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/* Fetch the names of all ports used in this task. */
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if (err = __mach_port_names (__mach_task_self (),
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&portnames, &nportnames,
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&porttypes, &nporttypes))
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LOSE;
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if (nportnames != nporttypes)
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{
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err = EGRATUITOUS;
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LOSE;
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}
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/* Get send rights for all the threads in this task.
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We want to avoid giving these rights to the child. */
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if (err = __task_threads (__mach_task_self (), &threads, &nthreads))
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LOSE;
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/* Get the child process's proc server port. We will insert it into
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the child with the same name as we use for our own proc server
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port; and we will need it to set the child's message port. */
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if (err = __proc_task2proc (_hurd_ports[INIT_PORT_PROC].port,
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newtask, &newproc))
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LOSE;
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/* Insert all our port rights into the child task. */
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thread_refs = sigthread_refs = 0;
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for (i = 0; i < nportnames; ++i)
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{
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if (porttypes[i] & MACH_PORT_TYPE_RECEIVE)
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{
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/* This is a receive right. We want to give the child task
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its own new receive right under the same name. */
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err = __mach_port_allocate_name (newtask,
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MACH_PORT_RIGHT_RECEIVE,
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portnames[i]);
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if (err == KERN_NAME_EXISTS)
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{
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/* It already has a right under this name (?!). Well,
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there is this bizarre old Mach IPC feature (in #ifdef
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MACH_IPC_COMPAT in the ukernel) which results in new
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tasks getting a new receive right for task special
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port number 2. What else might be going on I'm not
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sure. So let's check. */
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#if !MACH_IPC_COMPAT
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#define TASK_NOTIFY_PORT 2
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#endif
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assert (({ mach_port_t thisport, notify_port;
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mach_msg_type_name_t poly;
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(__task_get_special_port (newtask,
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TASK_NOTIFY_PORT,
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¬ify_port) == 0 &&
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__mach_port_extract_right
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(newtask,
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portnames[i],
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MACH_MSG_TYPE_MAKE_SEND,
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&thisport, &poly) == 0 &&
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(thisport == notify_port) &&
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__mach_port_deallocate (__mach_task_self (),
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thisport) == 0 &&
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__mach_port_deallocate (__mach_task_self (),
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notify_port) == 0);
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}));
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}
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else if (err)
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LOSE;
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if (porttypes[i] & MACH_PORT_TYPE_SEND)
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{
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/* Give the child as many send rights for its receive
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right as we have for ours. */
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mach_port_urefs_t refs;
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mach_port_t port;
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mach_msg_type_name_t poly;
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if (err = __mach_port_get_refs (__mach_task_self (),
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portnames[i],
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MACH_PORT_RIGHT_SEND,
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&refs))
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LOSE;
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if (err = __mach_port_extract_right (newtask,
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portnames[i],
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MACH_MSG_TYPE_MAKE_SEND,
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&port, &poly))
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LOSE;
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if (portnames[i] == _hurd_msgport)
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{
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/* We just created a receive right for the child's
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message port and are about to insert send rights
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for it. Now, while we happen to have a send right
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for it, give it to the proc server. */
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mach_port_t old;
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if (err = __proc_setmsgport (newproc, port, &old))
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LOSE;
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if (old != MACH_PORT_NULL)
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/* XXX what to do here? */
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__mach_port_deallocate (__mach_task_self (), old);
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/* The new task will receive its own exceptions
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on its message port. */
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if (err =
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#ifdef TASK_EXCEPTION_PORT
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__task_set_special_port (newtask,
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TASK_EXCEPTION_PORT,
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port)
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#elif defined (EXC_MASK_ALL)
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__task_set_exception_ports
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(newtask, EXC_MASK_ALL & ~(EXC_MASK_SYSCALL
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| EXC_MASK_MACH_SYSCALL
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| EXC_MASK_RPC_ALERT),
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port, EXCEPTION_DEFAULT, MACHINE_THREAD_STATE)
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#else
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# error task_set_exception_port?
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#endif
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)
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LOSE;
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}
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if (err = __mach_port_insert_right (newtask,
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portnames[i],
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port,
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MACH_MSG_TYPE_MOVE_SEND))
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LOSE;
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if (refs > 1 &&
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(err = __mach_port_mod_refs (newtask,
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portnames[i],
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MACH_PORT_RIGHT_SEND,
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refs - 1)))
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LOSE;
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}
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if (porttypes[i] & MACH_PORT_TYPE_SEND_ONCE)
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{
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/* Give the child a send-once right for its receive right,
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since we have one for ours. */
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mach_port_t port;
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mach_msg_type_name_t poly;
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if (err = __mach_port_extract_right
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(newtask,
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portnames[i],
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MACH_MSG_TYPE_MAKE_SEND_ONCE,
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&port, &poly))
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LOSE;
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if (err = __mach_port_insert_right
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(newtask,
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portnames[i], port,
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MACH_MSG_TYPE_MOVE_SEND_ONCE))
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LOSE;
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}
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}
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else if (porttypes[i] &
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(MACH_PORT_TYPE_SEND|MACH_PORT_TYPE_DEAD_NAME))
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{
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/* This is a send right or a dead name.
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Give the child as many references for it as we have. */
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mach_port_urefs_t refs, *record_refs = NULL;
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mach_port_t insert;
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mach_msg_type_name_t insert_type = MACH_MSG_TYPE_COPY_SEND;
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if (portnames[i] == newtask || portnames[i] == newproc)
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/* Skip the name we use for the child's task or proc ports. */
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continue;
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if (portnames[i] == __mach_task_self ())
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/* For the name we use for our own task port,
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insert the child's task port instead. */
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insert = newtask;
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else if (portnames[i] == _hurd_ports[INIT_PORT_PROC].port)
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{
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/* Use the proc server port for the new task. */
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insert = newproc;
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insert_type = MACH_MSG_TYPE_COPY_SEND;
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}
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else if (portnames[i] == ss->thread)
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{
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/* For the name we use for our own thread port, we will
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insert the thread port for the child main user thread
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after we create it. */
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insert = MACH_PORT_NULL;
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record_refs = &thread_refs;
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/* Allocate a dead name right for this name as a
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placeholder, so the kernel will not chose this name
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for any other new port (it might use it for one of the
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rights created when a thread is created). */
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if (err = __mach_port_allocate_name
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(newtask, MACH_PORT_RIGHT_DEAD_NAME, portnames[i]))
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LOSE;
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}
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else if (portnames[i] == _hurd_msgport_thread)
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/* For the name we use for our signal thread's thread port,
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we will insert the thread port for the child's signal
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thread after we create it. */
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{
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insert = MACH_PORT_NULL;
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record_refs = &sigthread_refs;
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/* Allocate a dead name right as a placeholder. */
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if (err = __mach_port_allocate_name
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(newtask, MACH_PORT_RIGHT_DEAD_NAME, portnames[i]))
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LOSE;
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}
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else
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{
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/* Skip the name we use for any of our own thread ports. */
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mach_msg_type_number_t j;
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for (j = 0; j < nthreads; ++j)
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if (portnames[i] == threads[j])
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break;
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if (j < nthreads)
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continue;
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/* Copy our own send right. */
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insert = portnames[i];
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}
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/* Find out how many user references we have for
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the send right with this name. */
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if (err = __mach_port_get_refs (__mach_task_self (),
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portnames[i],
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MACH_PORT_RIGHT_SEND,
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record_refs ?: &refs))
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LOSE;
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if (insert == MACH_PORT_NULL)
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continue;
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if (insert == portnames[i] &&
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(porttypes[i] & MACH_PORT_TYPE_DEAD_NAME))
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/* This is a dead name; allocate another dead name
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with the same name in the child. */
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allocate_dead_name:
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err = __mach_port_allocate_name (newtask,
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MACH_PORT_RIGHT_DEAD_NAME,
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portnames[i]);
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else
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/* Insert the chosen send right into the child. */
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err = __mach_port_insert_right (newtask,
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portnames[i],
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insert, insert_type);
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switch (err)
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{
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case KERN_NAME_EXISTS:
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{
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/* It already has a send right under this name (?!).
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Well, it starts out with a send right for its task
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port, and inherits the bootstrap and exception ports
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from us. */
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mach_port_t childport;
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mach_msg_type_name_t poly;
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assert (__mach_port_extract_right (newtask, portnames[i],
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MACH_MSG_TYPE_COPY_SEND,
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&childport,
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&poly) == 0 &&
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childport == insert &&
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__mach_port_deallocate (__mach_task_self (),
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childport) == 0);
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break;
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}
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case KERN_INVALID_CAPABILITY:
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/* The port just died. It was a send right,
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and now it's a dead name. */
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goto allocate_dead_name;
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default:
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LOSE;
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break;
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case KERN_SUCCESS:
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/* Give the child as many user references as we have. */
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if (refs > 1 &&
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(err = __mach_port_mod_refs (newtask,
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portnames[i],
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MACH_PORT_RIGHT_SEND,
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refs - 1)))
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LOSE;
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}
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}
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}
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/* Unlock the standard port cells. The child must unlock its own
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copies too. */
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for (i = 0; i < _hurd_nports; ++i)
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__spin_unlock (&_hurd_ports[i].lock);
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ports_locked = 0;
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/* All state has now been copied from the parent. It is safe to
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resume other parent threads. */
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resume_threads ();
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/* Create the child main user thread and signal thread. */
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if ((err = __thread_create (newtask, &thread)) ||
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(err = __thread_create (newtask, &sigthread)))
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LOSE;
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/* Insert send rights for those threads. We previously allocated
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dead name rights with the names we want to give the thread ports
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in the child as placeholders. Now deallocate them so we can use
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the names. */
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if ((err = __mach_port_deallocate (newtask, ss->thread)) ||
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(err = __mach_port_insert_right (newtask, ss->thread,
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thread, MACH_MSG_TYPE_COPY_SEND)))
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LOSE;
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/* We have one extra user reference created at the beginning of this
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function, accounted for by mach_port_names (and which will thus be
|
|
accounted for in the child below). This extra right gets consumed
|
|
in the child by the store into _hurd_sigthread in the child fork. */
|
|
if (thread_refs > 1 &&
|
|
(err = __mach_port_mod_refs (newtask, ss->thread,
|
|
MACH_PORT_RIGHT_SEND,
|
|
thread_refs)))
|
|
LOSE;
|
|
if ((_hurd_msgport_thread != MACH_PORT_NULL) /* Let user have none. */
|
|
&& ((err = __mach_port_deallocate (newtask, _hurd_msgport_thread)) ||
|
|
(err = __mach_port_insert_right (newtask, _hurd_msgport_thread,
|
|
sigthread,
|
|
MACH_MSG_TYPE_COPY_SEND))))
|
|
LOSE;
|
|
if (sigthread_refs > 1 &&
|
|
(err = __mach_port_mod_refs (newtask, _hurd_msgport_thread,
|
|
MACH_PORT_RIGHT_SEND,
|
|
sigthread_refs - 1)))
|
|
LOSE;
|
|
|
|
/* This seems like a convenient juncture to copy the proc server's
|
|
idea of what addresses our argv and envp are found at from the
|
|
parent into the child. Since we happen to know that the child
|
|
shares our memory image, it is we who should do this copying. */
|
|
{
|
|
vm_address_t argv, envp;
|
|
err = (__USEPORT (PROC, __proc_get_arg_locations (port, &argv, &envp))
|
|
?: __proc_set_arg_locations (newproc, argv, envp));
|
|
if (err)
|
|
LOSE;
|
|
}
|
|
|
|
/* Set the child signal thread up to run the msgport server function
|
|
using the same signal thread stack copied from our address space.
|
|
We fetch the state before longjmp'ing it so that miscellaneous
|
|
registers not affected by longjmp (such as i386 segment registers)
|
|
are in their normal default state. */
|
|
statecount = MACHINE_THREAD_STATE_COUNT;
|
|
if (err = __thread_get_state (_hurd_msgport_thread,
|
|
MACHINE_THREAD_STATE_FLAVOR,
|
|
(natural_t *) &state, &statecount))
|
|
LOSE;
|
|
#if STACK_GROWTH_UP
|
|
#define THREADVAR_SPACE (__hurd_threadvar_max \
|
|
* sizeof *__hurd_sightread_variables)
|
|
if (__hurd_sigthread_stack_base == 0)
|
|
{
|
|
state.SP &= __hurd_threadvar_stack_mask;
|
|
state.SP += __hurd_threadvar_stack_offset + THREADVAR_SPACE;
|
|
}
|
|
else
|
|
state.SP = __hurd_sigthread_stack_base;
|
|
#else
|
|
if (__hurd_sigthread_stack_end == 0)
|
|
{
|
|
/* The signal thread has a normal stack assigned by cthreads.
|
|
The threadvar_stack variables conveniently tell us how
|
|
to get to the highest address in the stack, just below
|
|
the per-thread variables. */
|
|
state.SP &= __hurd_threadvar_stack_mask;
|
|
state.SP += __hurd_threadvar_stack_offset;
|
|
}
|
|
else
|
|
state.SP = __hurd_sigthread_stack_end;
|
|
#endif
|
|
MACHINE_THREAD_STATE_SET_PC (&state,
|
|
(unsigned long int) _hurd_msgport_receive);
|
|
if (err = __thread_set_state (sigthread, MACHINE_THREAD_STATE_FLAVOR,
|
|
(natural_t *) &state, statecount))
|
|
LOSE;
|
|
/* We do not thread_resume SIGTHREAD here because the child
|
|
fork needs to do more setup before it can take signals. */
|
|
|
|
/* Set the child user thread up to return 1 from the setjmp above. */
|
|
_hurd_longjmp_thread_state (&state, env, 1);
|
|
if (err = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
|
|
(natural_t *) &state, statecount))
|
|
LOSE;
|
|
|
|
/* Get the PID of the child from the proc server. We must do this
|
|
before calling proc_child below, because at that point any
|
|
authorized POSIX.1 process may kill the child task with SIGKILL. */
|
|
if (err = __USEPORT (PROC, __proc_task2pid (port, newtask, &pid)))
|
|
LOSE;
|
|
|
|
/* Register the child with the proc server. It is important that
|
|
this be that last thing we do before starting the child thread
|
|
running. Once proc_child has been done for the task, it appears
|
|
as a POSIX.1 process. Any errors we get must be detected before
|
|
this point, and the child must have a message port so it responds
|
|
to POSIX.1 signals. */
|
|
if (err = __USEPORT (PROC, __proc_child (port, newtask)))
|
|
LOSE;
|
|
|
|
/* This must be the absolutely last thing we do; we can't assume that
|
|
the child will remain alive for even a moment once we do this. We
|
|
ignore errors because we have committed to the fork and are not
|
|
allowed to return them after the process becomes visible to
|
|
POSIX.1 (which happened right above when we called proc_child). */
|
|
(void) __thread_resume (thread);
|
|
|
|
lose:
|
|
if (ports_locked)
|
|
for (i = 0; i < _hurd_nports; ++i)
|
|
__spin_unlock (&_hurd_ports[i].lock);
|
|
|
|
resume_threads ();
|
|
|
|
if (newtask != MACH_PORT_NULL)
|
|
{
|
|
if (err)
|
|
__task_terminate (newtask);
|
|
__mach_port_deallocate (__mach_task_self (), newtask);
|
|
}
|
|
if (thread != MACH_PORT_NULL)
|
|
__mach_port_deallocate (__mach_task_self (), thread);
|
|
if (sigthread != MACH_PORT_NULL)
|
|
__mach_port_deallocate (__mach_task_self (), sigthread);
|
|
if (newproc != MACH_PORT_NULL)
|
|
__mach_port_deallocate (__mach_task_self (), newproc);
|
|
|
|
if (portnames)
|
|
__vm_deallocate (__mach_task_self (),
|
|
(vm_address_t) portnames,
|
|
nportnames * sizeof (*portnames));
|
|
if (porttypes)
|
|
__vm_deallocate (__mach_task_self (),
|
|
(vm_address_t) porttypes,
|
|
nporttypes * sizeof (*porttypes));
|
|
if (threads)
|
|
{
|
|
for (i = 0; i < nthreads; ++i)
|
|
__mach_port_deallocate (__mach_task_self (), threads[i]);
|
|
__vm_deallocate (__mach_task_self (),
|
|
(vm_address_t) threads,
|
|
nthreads * sizeof (*threads));
|
|
}
|
|
|
|
/* Run things that want to run in the parent to restore it to
|
|
normality. Usually prepare hooks and parent hooks are
|
|
symmetrical: the prepare hook arrests state in some way for the
|
|
fork, and the parent hook restores the state for the parent to
|
|
continue executing normally. */
|
|
RUN_HOOK (_hurd_fork_parent_hook, ());
|
|
}
|
|
else
|
|
{
|
|
struct hurd_sigstate *oldstates;
|
|
|
|
/* We are the child task. Unlock the standard port cells, which were
|
|
locked in the parent when we copied its memory. The parent has
|
|
inserted send rights with the names that were in the cells then. */
|
|
for (i = 0; i < _hurd_nports; ++i)
|
|
__spin_unlock (&_hurd_ports[i].lock);
|
|
|
|
/* We are one of the (exactly) two threads in this new task, we
|
|
will take the task-global signals. */
|
|
_hurd_sigthread = ss->thread;
|
|
|
|
/* Claim our sigstate structure and unchain the rest: the
|
|
threads existed in the parent task but don't exist in this
|
|
task (the child process). Delay freeing them until later
|
|
because some of the further setup and unlocking might be
|
|
required for free to work. Before we finish cleaning up,
|
|
we will reclaim the signal thread's sigstate structure (if
|
|
it had one). */
|
|
oldstates = _hurd_sigstates;
|
|
if (oldstates == ss)
|
|
oldstates = ss->next;
|
|
else
|
|
{
|
|
while (_hurd_sigstates->next != ss)
|
|
_hurd_sigstates = _hurd_sigstates->next;
|
|
_hurd_sigstates->next = ss->next;
|
|
}
|
|
ss->next = NULL;
|
|
_hurd_sigstates = ss;
|
|
__mutex_unlock (&_hurd_siglock);
|
|
|
|
/* Fetch our new process IDs from the proc server. No need to
|
|
refetch our pgrp; it is always inherited from the parent (so
|
|
_hurd_pgrp is already correct), and the proc server will send us a
|
|
proc_newids notification when it changes. */
|
|
err = __USEPORT (PROC, __proc_getpids (port, &_hurd_pid, &_hurd_ppid,
|
|
&_hurd_orphaned));
|
|
|
|
/* Forking clears the trace flag. */
|
|
__sigemptyset (&_hurdsig_traced);
|
|
|
|
/* Run things that want to run in the child task to set up. */
|
|
RUN_HOOK (_hurd_fork_child_hook, ());
|
|
|
|
/* Set up proc server-assisted fault recovery for the signal thread. */
|
|
_hurdsig_fault_init ();
|
|
|
|
/* Start the signal thread listening on the message port. */
|
|
if (!err)
|
|
err = __thread_resume (_hurd_msgport_thread);
|
|
|
|
/* Reclaim the signal thread's sigstate structure and free the
|
|
other old sigstate structures. */
|
|
while (oldstates != NULL)
|
|
{
|
|
struct hurd_sigstate *next = oldstates->next;
|
|
|
|
if (oldstates->thread == _hurd_msgport_thread)
|
|
{
|
|
/* If we have a second signal state structure then we
|
|
must have been through here before--not good. */
|
|
assert (_hurd_sigstates->next == 0);
|
|
_hurd_sigstates->next = oldstates;
|
|
oldstates->next = 0;
|
|
}
|
|
else
|
|
free (oldstates);
|
|
|
|
oldstates = next;
|
|
}
|
|
|
|
/* XXX what to do if we have any errors here? */
|
|
|
|
pid = 0;
|
|
}
|
|
|
|
/* Unlock things we locked before creating the child task.
|
|
They are locked in both the parent and child tasks. */
|
|
{
|
|
void *const *p;
|
|
for (p = symbol_set_first_element (_hurd_fork_locks);
|
|
! symbol_set_end_p (_hurd_fork_locks, p);
|
|
++p)
|
|
__mutex_unlock (*p);
|
|
}
|
|
|
|
_hurd_critical_section_unlock (ss);
|
|
|
|
return err ? __hurd_fail (err) : pid;
|
|
}
|
|
libc_hidden_def (__fork)
|
|
|
|
weak_alias (__fork, fork)
|