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-rw-r--r--hurd/intr-msg.c424
1 files changed, 0 insertions, 424 deletions
diff --git a/hurd/intr-msg.c b/hurd/intr-msg.c
deleted file mode 100644
index 636bd7b68d..0000000000
--- a/hurd/intr-msg.c
+++ /dev/null
@@ -1,424 +0,0 @@
-/* Replacement for mach_msg used in interruptible Hurd RPCs.
- Copyright (C) 1995-2017 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
-
-#include <mach.h>
-#include <mach/mig_errors.h>
-#include <mach/mig_support.h>
-#include <hurd/signal.h>
-#include <assert.h>
-
-#include "intr-msg.h"
-
-#ifdef NDR_CHAR_ASCII /* OSF Mach flavors have different names. */
-# define mig_reply_header_t mig_reply_error_t
-#endif
-
-error_t
-_hurd_intr_rpc_mach_msg (mach_msg_header_t *msg,
- mach_msg_option_t option,
- mach_msg_size_t send_size,
- mach_msg_size_t rcv_size,
- mach_port_t rcv_name,
- mach_msg_timeout_t timeout,
- mach_port_t notify)
-{
- error_t err;
- struct hurd_sigstate *ss;
- const mach_msg_option_t user_option = option;
- const mach_msg_timeout_t user_timeout = timeout;
-
- struct clobber
- {
-#ifdef NDR_CHAR_ASCII
- NDR_record_t ndr;
-#else
- mach_msg_type_t type;
-#endif
- error_t err;
- };
- union msg
- {
- mach_msg_header_t header;
- mig_reply_header_t reply;
- struct
- {
- mach_msg_header_t header;
-#ifdef NDR_CHAR_ASCII
- NDR_record_t ndr;
-#else
- int type;
-#endif
- int code;
- } check;
- struct
- {
- mach_msg_header_t header;
- struct clobber data;
- } request;
- };
- union msg *const m = (void *) msg;
- mach_msg_bits_t msgh_bits;
- mach_port_t remote_port;
- mach_msg_id_t msgid;
- struct clobber save_data;
-
- if ((option & (MACH_SEND_MSG|MACH_RCV_MSG)) != (MACH_SEND_MSG|MACH_RCV_MSG)
- || _hurd_msgport_thread == MACH_PORT_NULL)
- {
- /* Either this is not an RPC (i.e., only a send or only a receive),
- so it can't be interruptible; or, the signal thread is not set up
- yet, so we cannot do the normal signal magic. Do a normal,
- uninterruptible mach_msg call instead. */
- return __mach_msg (&m->header, option, send_size, rcv_size, rcv_name,
- timeout, notify);
- }
-
- ss = _hurd_self_sigstate ();
-
- /* Save state that gets clobbered by an EINTR reply message.
- We will need to restore it if we want to retry the RPC. */
- msgh_bits = m->header.msgh_bits;
- remote_port = m->header.msgh_remote_port;
- msgid = m->header.msgh_id;
- assert (rcv_size >= sizeof m->request);
- save_data = m->request.data;
-
- /* Tell the signal thread that we are doing an interruptible RPC on
- this port. If we get a signal and should return EINTR, the signal
- thread will set this variable to MACH_PORT_NULL. The RPC might
- return EINTR when some other thread gets a signal, in which case we
- want to restart our call. */
- ss->intr_port = m->header.msgh_remote_port;
-
- /* A signal may arrive here, after intr_port is set, but before the
- mach_msg system call. The signal handler might do an interruptible
- RPC, and clobber intr_port; then it would not be set properly when we
- actually did send the RPC, and a later signal wouldn't interrupt that
- RPC. So, _hurd_setup_sighandler saves intr_port in the sigcontext,
- and sigreturn restores it. */
-
- message:
-
- /* XXX
- At all points here (once SS->intr_port is set), the signal thread
- thinks we are "about to enter the syscall", and might mutate our
- return-value register. This is bogus.
- */
-
- if (ss->cancel)
- {
- /* We have been cancelled. Don't do an RPC at all. */
- ss->intr_port = MACH_PORT_NULL;
- ss->cancel = 0;
- return EINTR;
- }
-
- /* Note that the signal trampoline code might modify our OPTION! */
- err = INTR_MSG_TRAP (msg, option, send_size,
- rcv_size, rcv_name, timeout, notify);
-
- switch (err)
- {
- case MACH_RCV_TIMED_OUT:
- if (user_option & MACH_RCV_TIMEOUT)
- /* The real user RPC timed out. */
- break;
- else
- /* The operation was supposedly interrupted, but still has
- not returned. Declare it interrupted. */
- goto interrupted;
-
- case MACH_SEND_INTERRUPTED: /* RPC didn't get out. */
- if (!(option & MACH_SEND_MSG))
- {
- /* Oh yes, it did! Since we were not doing a message send,
- this return code cannot have come from the kernel!
- Instead, it was the signal thread mutating our state to tell
- us not to enter this RPC. However, we are already in the receive!
- Since the signal thread thought we weren't in the RPC yet,
- it didn't do an interrupt_operation.
- XXX */
- goto retry_receive;
- }
- /* FALLTHROUGH */
-
- /* These are the other codes that mean a pseudo-receive modified
- the message buffer and we might need to clean up the port rights. */
- case MACH_SEND_TIMED_OUT:
- case MACH_SEND_INVALID_NOTIFY:
-#ifdef MACH_SEND_NO_NOTIFY
- case MACH_SEND_NO_NOTIFY:
-#endif
-#ifdef MACH_SEND_NOTIFY_IN_PROGRESS
- case MACH_SEND_NOTIFY_IN_PROGRESS:
-#endif
- if (MACH_MSGH_BITS_REMOTE (msg->msgh_bits) == MACH_MSG_TYPE_MOVE_SEND)
- {
- __mach_port_deallocate (__mach_task_self (), msg->msgh_remote_port);
- msg->msgh_bits
- = (MACH_MSGH_BITS (MACH_MSG_TYPE_COPY_SEND,
- MACH_MSGH_BITS_LOCAL (msg->msgh_bits))
- | MACH_MSGH_BITS_OTHER (msg->msgh_bits));
- }
- if (msg->msgh_bits & MACH_MSGH_BITS_COMPLEX)
- {
-#ifndef MACH_MSG_PORT_DESCRIPTOR
- /* Check for MOVE_SEND rights in the message. These hold refs
- that we need to release in case the message is in fact never
- re-sent later. Since it might in fact be re-sent, we turn
- these into COPY_SEND's after deallocating the extra user ref;
- the caller is responsible for still holding a ref to go with
- the original COPY_SEND right, so the resend copies it again. */
-
- mach_msg_type_long_t *ty = (void *) (msg + 1);
- while ((void *) ty < (void *) msg + msg->msgh_size)
- {
- mach_msg_type_name_t name;
- mach_msg_type_size_t size;
- mach_msg_type_number_t number;
-
- inline void clean_ports (mach_port_t *ports, int dealloc)
- {
- mach_msg_type_number_t i;
- switch (name)
- {
- case MACH_MSG_TYPE_MOVE_SEND:
- for (i = 0; i < number; i++)
- __mach_port_deallocate (__mach_task_self (), *ports++);
- if (ty->msgtl_header.msgt_longform)
- ty->msgtl_name = MACH_MSG_TYPE_COPY_SEND;
- else
- ty->msgtl_header.msgt_name = MACH_MSG_TYPE_COPY_SEND;
- break;
- case MACH_MSG_TYPE_COPY_SEND:
- case MACH_MSG_TYPE_MOVE_RECEIVE:
- break;
- default:
- if (MACH_MSG_TYPE_PORT_ANY (name))
- assert (! "unexpected port type in interruptible RPC");
- }
- if (dealloc)
- __vm_deallocate (__mach_task_self (),
- (vm_address_t) ports,
- number * sizeof (mach_port_t));
- }
-
- if (ty->msgtl_header.msgt_longform)
- {
- name = ty->msgtl_name;
- size = ty->msgtl_size;
- number = ty->msgtl_number;
- ty = (void *) ty + sizeof (mach_msg_type_long_t);
- }
- else
- {
- name = ty->msgtl_header.msgt_name;
- size = ty->msgtl_header.msgt_size;
- number = ty->msgtl_header.msgt_number;
- ty = (void *) ty + sizeof (mach_msg_type_t);
- }
-
- if (ty->msgtl_header.msgt_inline)
- {
- clean_ports ((void *) ty, 0);
- /* calculate length of data in bytes, rounding up */
- ty = (void *) ty + (((((number * size) + 7) >> 3)
- + sizeof (mach_msg_type_t) - 1)
- &~ (sizeof (mach_msg_type_t) - 1));
- }
- else
- {
- clean_ports (*(void **) ty,
- ty->msgtl_header.msgt_deallocate);
- ty = (void *) ty + sizeof (void *);
- }
- }
-#else /* Untyped Mach IPC flavor. */
- mach_msg_body_t *body = (void *) (msg + 1);
- mach_msg_descriptor_t *desc = (void *) (body + 1);
- mach_msg_descriptor_t *desc_end = desc + body->msgh_descriptor_count;
- for (; desc < desc_end; ++desc)
- switch (desc->type.type)
- {
- case MACH_MSG_PORT_DESCRIPTOR:
- switch (desc->port.disposition)
- {
- case MACH_MSG_TYPE_MOVE_SEND:
- __mach_port_deallocate (mach_task_self (),
- desc->port.name);
- desc->port.disposition = MACH_MSG_TYPE_COPY_SEND;
- break;
- case MACH_MSG_TYPE_COPY_SEND:
- case MACH_MSG_TYPE_MOVE_RECEIVE:
- break;
- default:
- assert (! "unexpected port type in interruptible RPC");
- }
- break;
- case MACH_MSG_OOL_DESCRIPTOR:
- if (desc->out_of_line.deallocate)
- __vm_deallocate (__mach_task_self (),
- (vm_address_t) desc->out_of_line.address,
- desc->out_of_line.size);
- break;
- case MACH_MSG_OOL_PORTS_DESCRIPTOR:
- switch (desc->ool_ports.disposition)
- {
- case MACH_MSG_TYPE_MOVE_SEND:
- {
- mach_msg_size_t i;
- const mach_port_t *ports = desc->ool_ports.address;
- for (i = 0; i < desc->ool_ports.count; ++i)
- __mach_port_deallocate (__mach_task_self (), ports[i]);
- desc->ool_ports.disposition = MACH_MSG_TYPE_COPY_SEND;
- break;
- }
- case MACH_MSG_TYPE_COPY_SEND:
- case MACH_MSG_TYPE_MOVE_RECEIVE:
- break;
- default:
- assert (! "unexpected port type in interruptible RPC");
- }
- if (desc->ool_ports.deallocate)
- __vm_deallocate (__mach_task_self (),
- (vm_address_t) desc->ool_ports.address,
- desc->ool_ports.count
- * sizeof (mach_port_t));
- break;
- default:
- assert (! "unexpected descriptor type in interruptible RPC");
- }
-#endif
- }
- break;
-
- case EINTR:
- /* Either the process was stopped and continued,
- or the server doesn't support interrupt_operation. */
- if (ss->intr_port != MACH_PORT_NULL)
- /* If this signal was for us and it should interrupt calls, the
- signal thread will have cleared SS->intr_port.
- Since it's not cleared, the signal was for another thread,
- or SA_RESTART is set. Restart the interrupted call. */
- {
- /* Make sure we have a valid reply port. The one we were using
- may have been destroyed by interruption. */
- m->header.msgh_local_port = rcv_name = __mig_get_reply_port ();
- m->header.msgh_bits = msgh_bits;
- option = user_option;
- timeout = user_timeout;
- goto message;
- }
- /* FALLTHROUGH */
-
- case MACH_RCV_PORT_DIED:
- /* Server didn't respond to interrupt_operation,
- so the signal thread destroyed the reply port. */
- /* FALLTHROUGH */
-
- interrupted:
- err = EINTR;
-
- /* The EINTR return indicates cancellation, so clear the flag. */
- ss->cancel = 0;
- break;
-
- case MACH_RCV_INTERRUPTED: /* RPC sent; no reply. */
- option &= ~MACH_SEND_MSG; /* Don't send again. */
- retry_receive:
- if (ss->intr_port == MACH_PORT_NULL)
- {
- /* This signal or cancellation was for us. We need to wait for
- the reply, but not hang forever. */
- option |= MACH_RCV_TIMEOUT;
- /* Never decrease the user's timeout. */
- if (!(user_option & MACH_RCV_TIMEOUT)
- || timeout > _hurd_interrupted_rpc_timeout)
- timeout = _hurd_interrupted_rpc_timeout;
- }
- else
- {
- option = user_option;
- timeout = user_timeout;
- }
- goto message; /* Retry the receive. */
-
- case MACH_MSG_SUCCESS:
- {
- /* We got a reply. Was it EINTR? */
-#ifdef MACH_MSG_TYPE_BIT
- const union
- {
- mach_msg_type_t t;
- int i;
- } check =
- { t: { MACH_MSG_TYPE_INTEGER_T, sizeof (integer_t) * 8,
- 1, TRUE, FALSE, FALSE, 0 } };
-#endif
-
- if (m->reply.RetCode == EINTR &&
- m->header.msgh_size == sizeof m->reply &&
-#ifdef MACH_MSG_TYPE_BIT
- m->check.type == check.i &&
-#endif
- !(m->header.msgh_bits & MACH_MSGH_BITS_COMPLEX))
- {
- /* It is indeed EINTR. Is the interrupt for us? */
- if (ss->intr_port != MACH_PORT_NULL)
- {
- /* Nope; repeat the RPC.
- XXX Resources moved? */
-
- assert (m->header.msgh_id == msgid + 100);
-
- /* We know we have a valid reply port, because we just
- received the EINTR reply on it. Restore it and the
- other fields in the message header needed for send,
- since the header now reflects receipt of the reply. */
- m->header.msgh_local_port = rcv_name;
- m->header.msgh_remote_port = remote_port;
- m->header.msgh_id = msgid;
- m->header.msgh_bits = msgh_bits;
- /* Restore the two words clobbered by the reply data. */
- m->request.data = save_data;
-
- /* Restore the original mach_msg options.
- OPTION may have had MACH_RCV_TIMEOUT added,
- and/or MACH_SEND_MSG removed. */
- option = user_option;
- timeout = user_timeout;
-
- /* Now we are ready to repeat the original message send. */
- goto message;
- }
- else
- /* The EINTR return indicates cancellation,
- so clear the flag. */
- ss->cancel = 0;
- }
- }
- break;
-
- default: /* Quiet -Wswitch-enum. */
- break;
- }
-
- ss->intr_port = MACH_PORT_NULL;
-
- return err;
-}