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-rw-r--r--src/3rd_party/dbus-1.7.8/dbus/dbus-socket-set-epoll.c371
1 files changed, 0 insertions, 371 deletions
diff --git a/src/3rd_party/dbus-1.7.8/dbus/dbus-socket-set-epoll.c b/src/3rd_party/dbus-1.7.8/dbus/dbus-socket-set-epoll.c
deleted file mode 100644
index 4cd9a563af..0000000000
--- a/src/3rd_party/dbus-1.7.8/dbus/dbus-socket-set-epoll.c
+++ /dev/null
@@ -1,371 +0,0 @@
-/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
-/* dbus-socket-set-epoll.c - a socket set implemented via Linux epoll(4)
- *
- * Copyright © 2011 Nokia Corporation
- *
- * Licensed under the Academic Free License version 2.1
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301 USA
- *
- */
-
-#include <config.h>
-#include "dbus-socket-set.h"
-
-#include <dbus/dbus-internals.h>
-#include <dbus/dbus-sysdeps.h>
-
-#ifndef __linux__
-# error This file is for Linux epoll(4)
-#endif
-
-#include <errno.h>
-#include <fcntl.h>
-#include <sys/epoll.h>
-#include <unistd.h>
-
-#ifndef DOXYGEN_SHOULD_SKIP_THIS
-
-typedef struct {
- DBusSocketSet parent;
- int epfd;
-} DBusSocketSetEpoll;
-
-static inline DBusSocketSetEpoll *
-socket_set_epoll_cast (DBusSocketSet *set)
-{
- _dbus_assert (set->cls == &_dbus_socket_set_epoll_class);
- return (DBusSocketSetEpoll *) set;
-}
-
-/* this is safe to call on a partially-allocated socket set */
-static void
-socket_set_epoll_free (DBusSocketSet *set)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
-
- if (self == NULL)
- return;
-
- if (self->epfd != -1)
- close (self->epfd);
-
- dbus_free (self);
-}
-
-DBusSocketSet *
-_dbus_socket_set_epoll_new (void)
-{
- DBusSocketSetEpoll *self;
-
- self = dbus_new0 (DBusSocketSetEpoll, 1);
-
- if (self == NULL)
- return NULL;
-
- self->parent.cls = &_dbus_socket_set_epoll_class;
-
- self->epfd = epoll_create1 (EPOLL_CLOEXEC);
-
- if (self->epfd == -1)
- {
- int flags;
-
- /* the size hint is ignored unless you have a rather old kernel,
- * but must be positive on some versions, so just pick something
- * arbitrary; it's a hint, not a limit */
- self->epfd = epoll_create (42);
-
- flags = fcntl (self->epfd, F_GETFD, 0);
-
- if (flags != -1)
- fcntl (self->epfd, F_SETFD, flags | FD_CLOEXEC);
- }
-
- if (self->epfd == -1)
- {
- socket_set_epoll_free ((DBusSocketSet *) self);
- return NULL;
- }
-
- return (DBusSocketSet *) self;
-}
-
-static uint32_t
-watch_flags_to_epoll_events (unsigned int flags)
-{
- uint32_t events = 0;
-
- if (flags & DBUS_WATCH_READABLE)
- events |= EPOLLIN;
- if (flags & DBUS_WATCH_WRITABLE)
- events |= EPOLLOUT;
-
- return events;
-}
-
-static unsigned int
-epoll_events_to_watch_flags (uint32_t events)
-{
- short flags = 0;
-
- if (events & EPOLLIN)
- flags |= DBUS_WATCH_READABLE;
- if (events & EPOLLOUT)
- flags |= DBUS_WATCH_WRITABLE;
- if (events & EPOLLHUP)
- flags |= DBUS_WATCH_HANGUP;
- if (events & EPOLLERR)
- flags |= DBUS_WATCH_ERROR;
-
- return flags;
-}
-
-static dbus_bool_t
-socket_set_epoll_add (DBusSocketSet *set,
- int fd,
- unsigned int flags,
- dbus_bool_t enabled)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
- struct epoll_event event;
- int err;
-
- event.data.fd = fd;
-
- if (enabled)
- {
- event.events = watch_flags_to_epoll_events (flags);
- }
- else
- {
- /* We need to add *something* to reserve space in the kernel's data
- * structures: see socket_set_epoll_disable for more details */
- event.events = EPOLLET;
- }
-
- if (epoll_ctl (self->epfd, EPOLL_CTL_ADD, fd, &event) == 0)
- return TRUE;
-
- /* Anything except ENOMEM, ENOSPC means we have an internal error. */
- err = errno;
- switch (err)
- {
- case ENOMEM:
- case ENOSPC:
- /* be silent: this is basically OOM, which our callers are expected
- * to cope with */
- break;
-
- case EBADF:
- _dbus_warn ("Bad fd %d\n", fd);
- break;
-
- case EEXIST:
- _dbus_warn ("fd %d added and then added again\n", fd);
- break;
-
- default:
- _dbus_warn ("Misc error when trying to watch fd %d: %s\n", fd,
- strerror (err));
- break;
- }
-
- return FALSE;
-}
-
-static void
-socket_set_epoll_enable (DBusSocketSet *set,
- int fd,
- unsigned int flags)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
- struct epoll_event event;
- int err;
-
- event.data.fd = fd;
- event.events = watch_flags_to_epoll_events (flags);
-
- if (epoll_ctl (self->epfd, EPOLL_CTL_MOD, fd, &event) == 0)
- return;
-
- err = errno;
-
- /* Enabling a file descriptor isn't allowed to fail, even for OOM, so we
- * do our best to avoid all of these. */
- switch (err)
- {
- case EBADF:
- _dbus_warn ("Bad fd %d\n", fd);
- break;
-
- case ENOENT:
- _dbus_warn ("fd %d enabled before it was added\n", fd);
- break;
-
- case ENOMEM:
- _dbus_warn ("Insufficient memory to change watch for fd %d\n", fd);
- break;
-
- default:
- _dbus_warn ("Misc error when trying to watch fd %d: %s\n", fd,
- strerror (err));
- break;
- }
-}
-
-static void
-socket_set_epoll_disable (DBusSocketSet *set,
- int fd)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
- struct epoll_event event;
- int err;
-
- /* The naive thing to do would be EPOLL_CTL_DEL, but that'll probably
- * free resources in the kernel. When we come to do socket_set_epoll_enable,
- * there might not be enough resources to bring it back!
- *
- * The next idea you might have is to set the flags to 0. However, events
- * always trigger on EPOLLERR and EPOLLHUP, even if libdbus isn't actually
- * delivering them to a DBusWatch. Because epoll is level-triggered by
- * default, we'll busy-loop on an unhandled error or hangup; not good.
- *
- * So, let's set it to be edge-triggered: then the worst case is that
- * we return from poll immediately on one iteration, ignore it because no
- * watch is enabled, then go back to normal. When we re-enable a watch
- * we'll switch back to level-triggered and be notified again (verified to
- * work on 2.6.32). Compile this file with -DTEST_BEHAVIOUR_OF_EPOLLET for
- * test code.
- */
- event.data.fd = fd;
- event.events = EPOLLET;
-
- if (epoll_ctl (self->epfd, EPOLL_CTL_MOD, fd, &event) == 0)
- return;
-
- err = errno;
- _dbus_warn ("Error when trying to watch fd %d: %s\n", fd,
- strerror (err));
-}
-
-static void
-socket_set_epoll_remove (DBusSocketSet *set,
- int fd)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
- int err;
- /* Kernels < 2.6.9 require a non-NULL struct pointer, even though its
- * contents are ignored */
- struct epoll_event dummy = { 0 };
-
- if (epoll_ctl (self->epfd, EPOLL_CTL_DEL, fd, &dummy) == 0)
- return;
-
- err = errno;
- _dbus_warn ("Error when trying to remove fd %d: %s\n", fd, strerror (err));
-}
-
-/* Optimally, this should be the same as in DBusLoop: we use it to translate
- * between struct epoll_event and DBusSocketEvent without allocating heap
- * memory. */
-#define N_STACK_DESCRIPTORS 64
-
-static int
-socket_set_epoll_poll (DBusSocketSet *set,
- DBusSocketEvent *revents,
- int max_events,
- int timeout_ms)
-{
- DBusSocketSetEpoll *self = socket_set_epoll_cast (set);
- struct epoll_event events[N_STACK_DESCRIPTORS];
- int n_ready;
- int i;
-
- _dbus_assert (max_events > 0);
-
- n_ready = epoll_wait (self->epfd, events,
- MIN (_DBUS_N_ELEMENTS (events), max_events),
- timeout_ms);
-
- if (n_ready <= 0)
- return n_ready;
-
- for (i = 0; i < n_ready; i++)
- {
- revents[i].fd = events[i].data.fd;
- revents[i].flags = epoll_events_to_watch_flags (events[i].events);
- }
-
- return n_ready;
-}
-
-DBusSocketSetClass _dbus_socket_set_epoll_class = {
- socket_set_epoll_free,
- socket_set_epoll_add,
- socket_set_epoll_remove,
- socket_set_epoll_enable,
- socket_set_epoll_disable,
- socket_set_epoll_poll
-};
-
-#ifdef TEST_BEHAVIOUR_OF_EPOLLET
-/* usage: cat /dev/null | ./epoll
- *
- * desired output:
- * ctl ADD: 0
- * wait for HUP, edge-triggered: 1
- * wait for HUP again: 0
- * ctl MOD: 0
- * wait for HUP: 1
- */
-
-#include <sys/epoll.h>
-
-#include <stdio.h>
-
-int
-main (void)
-{
- struct epoll_event input;
- struct epoll_event output;
- int epfd = epoll_create1 (EPOLL_CLOEXEC);
- int fd = 0; /* stdin */
- int ret;
-
- input.events = EPOLLHUP | EPOLLET;
- ret = epoll_ctl (epfd, EPOLL_CTL_ADD, fd, &input);
- printf ("ctl ADD: %d\n", ret);
-
- ret = epoll_wait (epfd, &output, 1, -1);
- printf ("wait for HUP, edge-triggered: %d\n", ret);
-
- ret = epoll_wait (epfd, &output, 1, 1);
- printf ("wait for HUP again: %d\n", ret);
-
- input.events = EPOLLHUP;
- ret = epoll_ctl (epfd, EPOLL_CTL_MOD, fd, &input);
- printf ("ctl MOD: %d\n", ret);
-
- ret = epoll_wait (epfd, &output, 1, -1);
- printf ("wait for HUP: %d\n", ret);
-
- return 0;
-}
-
-#endif /* TEST_BEHAVIOUR_OF_EPOLLET */
-
-#endif /* !DOXYGEN_SHOULD_SKIP_THIS */
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