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-rw-r--r--hurd/hurdselect.c491
1 files changed, 0 insertions, 491 deletions
diff --git a/hurd/hurdselect.c b/hurd/hurdselect.c
deleted file mode 100644
index 8dc7c76995..0000000000
--- a/hurd/hurdselect.c
+++ /dev/null
@@ -1,491 +0,0 @@
-/* Guts of both `select' and `poll' for Hurd.
- Copyright (C) 1991-2017 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 <sys/types.h>
-#include <sys/poll.h>
-#include <hurd.h>
-#include <hurd/fd.h>
-#include <stdlib.h>
-#include <string.h>
-#include <assert.h>
-#include <stdint.h>
-
-/* All user select types. */
-#define SELECT_ALL (SELECT_READ | SELECT_WRITE | SELECT_URG)
-
-/* Used to record that a particular select rpc returned. Must be distinct
- from SELECT_ALL (which better not have the high bit set). */
-#define SELECT_RETURNED ((SELECT_ALL << 1) & ~SELECT_ALL)
-
-/* Check the first NFDS descriptors either in POLLFDS (if nonnnull) or in
- each of READFDS, WRITEFDS, EXCEPTFDS that is nonnull. If TIMEOUT is not
- NULL, time out after waiting the interval specified therein. Returns
- the number of ready descriptors, or -1 for errors. */
-int
-_hurd_select (int nfds,
- struct pollfd *pollfds,
- fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
- const struct timespec *timeout, const sigset_t *sigmask)
-{
- int i;
- mach_port_t portset;
- int got;
- error_t err;
- fd_set rfds, wfds, xfds;
- int firstfd, lastfd;
- mach_msg_timeout_t to = 0;
- struct
- {
- struct hurd_userlink ulink;
- struct hurd_fd *cell;
- mach_port_t io_port;
- int type;
- mach_port_t reply_port;
- } d[nfds];
- sigset_t oset;
-
- union typeword /* Use this to avoid unkosher casts. */
- {
- mach_msg_type_t type;
- uint32_t word;
- };
- assert (sizeof (union typeword) == sizeof (mach_msg_type_t));
- assert (sizeof (uint32_t) == sizeof (mach_msg_type_t));
-
- if (nfds < 0 || (pollfds == NULL && nfds > FD_SETSIZE))
- {
- errno = EINVAL;
- return -1;
- }
-
- if (timeout != NULL)
- {
- if (timeout->tv_sec < 0 || timeout->tv_nsec < 0)
- {
- errno = EINVAL;
- return -1;
- }
-
- to = (timeout->tv_sec * 1000 +
- (timeout->tv_nsec + 999999) / 1000000);
- }
-
- if (sigmask && __sigprocmask (SIG_SETMASK, sigmask, &oset))
- return -1;
-
- if (pollfds)
- {
- /* Collect interesting descriptors from the user's `pollfd' array.
- We do a first pass that reads the user's array before taking
- any locks. The second pass then only touches our own stack,
- and gets the port references. */
-
- for (i = 0; i < nfds; ++i)
- if (pollfds[i].fd >= 0)
- {
- int type = 0;
- if (pollfds[i].events & POLLIN)
- type |= SELECT_READ;
- if (pollfds[i].events & POLLOUT)
- type |= SELECT_WRITE;
- if (pollfds[i].events & POLLPRI)
- type |= SELECT_URG;
-
- d[i].io_port = pollfds[i].fd;
- d[i].type = type;
- }
- else
- d[i].type = 0;
-
- HURD_CRITICAL_BEGIN;
- __mutex_lock (&_hurd_dtable_lock);
-
- for (i = 0; i < nfds; ++i)
- if (d[i].type != 0)
- {
- const int fd = (int) d[i].io_port;
-
- if (fd < _hurd_dtablesize)
- {
- d[i].cell = _hurd_dtable[fd];
- d[i].io_port = _hurd_port_get (&d[i].cell->port, &d[i].ulink);
- if (d[i].io_port != MACH_PORT_NULL)
- continue;
- }
-
- /* If one descriptor is bogus, we fail completely. */
- while (i-- > 0)
- if (d[i].type != 0)
- _hurd_port_free (&d[i].cell->port,
- &d[i].ulink, d[i].io_port);
- break;
- }
-
- __mutex_unlock (&_hurd_dtable_lock);
- HURD_CRITICAL_END;
-
- if (i < nfds)
- {
- if (sigmask)
- __sigprocmask (SIG_SETMASK, &oset, NULL);
- errno = EBADF;
- return -1;
- }
-
- lastfd = i - 1;
- firstfd = i == 0 ? lastfd : 0;
- }
- else
- {
- /* Collect interested descriptors from the user's fd_set arguments.
- Use local copies so we can't crash from user bogosity. */
-
- if (readfds == NULL)
- FD_ZERO (&rfds);
- else
- rfds = *readfds;
- if (writefds == NULL)
- FD_ZERO (&wfds);
- else
- wfds = *writefds;
- if (exceptfds == NULL)
- FD_ZERO (&xfds);
- else
- xfds = *exceptfds;
-
- HURD_CRITICAL_BEGIN;
- __mutex_lock (&_hurd_dtable_lock);
-
- if (nfds > _hurd_dtablesize)
- nfds = _hurd_dtablesize;
-
- /* Collect the ports for interesting FDs. */
- firstfd = lastfd = -1;
- for (i = 0; i < nfds; ++i)
- {
- int type = 0;
- if (readfds != NULL && FD_ISSET (i, &rfds))
- type |= SELECT_READ;
- if (writefds != NULL && FD_ISSET (i, &wfds))
- type |= SELECT_WRITE;
- if (exceptfds != NULL && FD_ISSET (i, &xfds))
- type |= SELECT_URG;
- d[i].type = type;
- if (type)
- {
- d[i].cell = _hurd_dtable[i];
- d[i].io_port = _hurd_port_get (&d[i].cell->port, &d[i].ulink);
- if (d[i].io_port == MACH_PORT_NULL)
- {
- /* If one descriptor is bogus, we fail completely. */
- while (i-- > 0)
- if (d[i].type != 0)
- _hurd_port_free (&d[i].cell->port, &d[i].ulink,
- d[i].io_port);
- break;
- }
- lastfd = i;
- if (firstfd == -1)
- firstfd = i;
- }
- }
-
- __mutex_unlock (&_hurd_dtable_lock);
- HURD_CRITICAL_END;
-
- if (i < nfds)
- {
- if (sigmask)
- __sigprocmask (SIG_SETMASK, &oset, NULL);
- errno = EBADF;
- return -1;
- }
- }
-
-
- err = 0;
- got = 0;
-
- /* Send them all io_select request messages. */
-
- if (firstfd == -1)
- /* But not if there were no ports to deal with at all.
- We are just a pure timeout. */
- portset = __mach_reply_port ();
- else
- {
- portset = MACH_PORT_NULL;
-
- for (i = firstfd; i <= lastfd; ++i)
- if (d[i].type)
- {
- int type = d[i].type;
- d[i].reply_port = __mach_reply_port ();
- err = __io_select (d[i].io_port, d[i].reply_port,
- /* Poll only if there's a single descriptor. */
- (firstfd == lastfd) ? to : 0,
- &type);
- switch (err)
- {
- case MACH_RCV_TIMED_OUT:
- /* No immediate response. This is normal. */
- err = 0;
- if (firstfd == lastfd)
- /* When there's a single descriptor, we don't need a
- portset, so just pretend we have one, but really
- use the single reply port. */
- portset = d[i].reply_port;
- else if (got == 0)
- /* We've got multiple reply ports, so we need a port set to
- multiplex them. */
- {
- /* We will wait again for a reply later. */
- if (portset == MACH_PORT_NULL)
- /* Create the portset to receive all the replies on. */
- err = __mach_port_allocate (__mach_task_self (),
- MACH_PORT_RIGHT_PORT_SET,
- &portset);
- if (! err)
- /* Put this reply port in the port set. */
- __mach_port_move_member (__mach_task_self (),
- d[i].reply_port, portset);
- }
- break;
-
- default:
- /* No other error should happen. Callers of select
- don't expect to see errors, so we simulate
- readiness of the erring object and the next call
- hopefully will get the error again. */
- type = SELECT_ALL;
- /* FALLTHROUGH */
-
- case 0:
- /* We got an answer. */
- if ((type & SELECT_ALL) == 0)
- /* Bogus answer; treat like an error, as a fake positive. */
- type = SELECT_ALL;
-
- /* This port is already ready already. */
- d[i].type &= type;
- d[i].type |= SELECT_RETURNED;
- ++got;
- break;
- }
- _hurd_port_free (&d[i].cell->port, &d[i].ulink, d[i].io_port);
- }
- }
-
- /* Now wait for reply messages. */
- if (!err && got == 0)
- {
- /* Now wait for io_select_reply messages on PORT,
- timing out as appropriate. */
-
- union
- {
- mach_msg_header_t head;
-#ifdef MACH_MSG_TRAILER_MINIMUM_SIZE
- struct
- {
- mach_msg_header_t head;
- NDR_record_t ndr;
- error_t err;
- } error;
- struct
- {
- mach_msg_header_t head;
- NDR_record_t ndr;
- error_t err;
- int result;
- mach_msg_trailer_t trailer;
- } success;
-#else
- struct
- {
- mach_msg_header_t head;
- union typeword err_type;
- error_t err;
- } error;
- struct
- {
- mach_msg_header_t head;
- union typeword err_type;
- error_t err;
- union typeword result_type;
- int result;
- } success;
-#endif
- } msg;
- mach_msg_option_t options = (timeout == NULL ? 0 : MACH_RCV_TIMEOUT);
- error_t msgerr;
- while ((msgerr = __mach_msg (&msg.head,
- MACH_RCV_MSG | MACH_RCV_INTERRUPT | options,
- 0, sizeof msg, portset, to,
- MACH_PORT_NULL)) == MACH_MSG_SUCCESS)
- {
- /* We got a message. Decode it. */
-#define IO_SELECT_REPLY_MSGID (21012 + 100) /* XXX */
-#ifdef MACH_MSG_TYPE_BIT
- const union typeword inttype =
- { type:
- { MACH_MSG_TYPE_INTEGER_T, sizeof (integer_t) * 8, 1, 1, 0, 0 }
- };
-#endif
- if (msg.head.msgh_id == IO_SELECT_REPLY_MSGID &&
- msg.head.msgh_size >= sizeof msg.error &&
- !(msg.head.msgh_bits & MACH_MSGH_BITS_COMPLEX) &&
-#ifdef MACH_MSG_TYPE_BIT
- msg.error.err_type.word == inttype.word
-#endif
- )
- {
- /* This is a properly formatted message so far.
- See if it is a success or a failure. */
- if (msg.error.err == EINTR &&
- msg.head.msgh_size == sizeof msg.error)
- {
- /* EINTR response; poll for further responses
- and then return quickly. */
- err = EINTR;
- goto poll;
- }
- if (msg.error.err ||
- msg.head.msgh_size != sizeof msg.success ||
-#ifdef MACH_MSG_TYPE_BIT
- msg.success.result_type.word != inttype.word ||
-#endif
- (msg.success.result & SELECT_ALL) == 0)
- {
- /* Error or bogus reply. Simulate readiness. */
- __mach_msg_destroy (&msg.head);
- msg.success.result = SELECT_ALL;
- }
-
- /* Look up the respondent's reply port and record its
- readiness. */
- {
- int had = got;
- if (firstfd != -1)
- for (i = firstfd; i <= lastfd; ++i)
- if (d[i].type
- && d[i].reply_port == msg.head.msgh_local_port)
- {
- d[i].type &= msg.success.result;
- d[i].type |= SELECT_RETURNED;
- ++got;
- }
- assert (got > had);
- }
- }
-
- if (msg.head.msgh_remote_port != MACH_PORT_NULL)
- __mach_port_deallocate (__mach_task_self (),
- msg.head.msgh_remote_port);
-
- if (got)
- poll:
- {
- /* Poll for another message. */
- to = 0;
- options |= MACH_RCV_TIMEOUT;
- }
- }
-
- if (msgerr == MACH_RCV_INTERRUPTED)
- /* Interruption on our side (e.g. signal reception). */
- err = EINTR;
-
- if (got)
- /* At least one descriptor is known to be ready now, so we will
- return success. */
- err = 0;
- }
-
- if (firstfd != -1)
- for (i = firstfd; i <= lastfd; ++i)
- if (d[i].type)
- __mach_port_destroy (__mach_task_self (), d[i].reply_port);
- if (firstfd == -1 || (firstfd != lastfd && portset != MACH_PORT_NULL))
- /* Destroy PORTSET, but only if it's not actually the reply port for a
- single descriptor (in which case it's destroyed in the previous loop;
- not doing it here is just a bit more efficient). */
- __mach_port_destroy (__mach_task_self (), portset);
-
- if (err)
- {
- if (sigmask)
- __sigprocmask (SIG_SETMASK, &oset, NULL);
- return __hurd_fail (err);
- }
-
- if (pollfds)
- /* Fill in the `revents' members of the user's array. */
- for (i = 0; i < nfds; ++i)
- {
- int type = d[i].type;
- int_fast16_t revents = 0;
-
- if (type & SELECT_RETURNED)
- {
- if (type & SELECT_READ)
- revents |= POLLIN;
- if (type & SELECT_WRITE)
- revents |= POLLOUT;
- if (type & SELECT_URG)
- revents |= POLLPRI;
- }
-
- pollfds[i].revents = revents;
- }
- else
- {
- /* Below we recalculate GOT to include an increment for each operation
- allowed on each fd. */
- got = 0;
-
- /* Set the user bitarrays. We only ever have to clear bits, as all
- desired ones are initially set. */
- if (firstfd != -1)
- for (i = firstfd; i <= lastfd; ++i)
- {
- int type = d[i].type;
-
- if ((type & SELECT_RETURNED) == 0)
- type = 0;
-
- if (type & SELECT_READ)
- got++;
- else if (readfds)
- FD_CLR (i, readfds);
- if (type & SELECT_WRITE)
- got++;
- else if (writefds)
- FD_CLR (i, writefds);
- if (type & SELECT_URG)
- got++;
- else if (exceptfds)
- FD_CLR (i, exceptfds);
- }
- }
-
- if (sigmask && __sigprocmask (SIG_SETMASK, &oset, NULL))
- return -1;
-
- return got;
-}
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