r5373: prepare infrastructure for maing different events

implementations possible

metze
(This used to be commit dd77ec754b811feb147458d76fa16833767dccea)

1 files changed, 0 insertions, 540 deletions

diff --git a/source4/lib/events/events.c b/source4/lib/events/events.c
deleted file mode 100644
index 9783603759..0000000000
--- a/source4/lib/events/events.c
+++ /dev/null
@@ -1,540 +0,0 @@
-/* 
-   Unix SMB/CIFS implementation.
-   main select loop and event handling
-   Copyright (C) Andrew Tridgell 2003
-   
-   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., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-/*
-  PLEASE READ THIS BEFORE MODIFYING!
-
-  This module is a general abstraction for the main select loop and
-  event handling. Do not ever put any localised hacks in here, instead
-  register one of the possible event types and implement that event
-  somewhere else.
-
-  There are 2 types of event handling that are handled in this module:
-
-  1) a file descriptor becoming readable or writeable. This is mostly
-     used for network sockets, but can be used for any type of file
-     descriptor. You may only register one handler for each file
-     descriptor/io combination or you will get unpredictable results
-     (this means that you can have a handler for read events, and a
-     separate handler for write events, but not two handlers that are
-     both handling read events)
-
-  2) a timed event. You can register an event that happens at a
-     specific time.  You can register as many of these as you
-     like. They are single shot - add a new timed event in the event
-     handler to get another event.
-
-  To setup a set of events you first need to create a event_context
-  structure using the function event_context_init(); This returns a
-  'struct event_context' that you use in all subsequent calls.
-
-  After that you can add/remove events that you are interested in
-  using event_add_*() and talloc_free()
-
-  Finally, you call event_loop_wait() to block waiting for one of the
-  events to occor. In normal operation event_loop_wait() will loop
-  forever.
-
-*/
-
-#include "includes.h"
-#include "system/time.h"
-#include "system/select.h"
-#include "system/filesys.h"
-#include "dlinklist.h"
-#include "lib/events/events.h"
-
-/* use epoll if it is available */
-#if defined(HAVE_EPOLL_CREATE) && defined(HAVE_SYS_EPOLL_H)
-#define WITH_EPOLL 1
-#endif
-
-#if WITH_EPOLL
-#include <sys/epoll.h>
-#endif
-
-struct event_context {	
-	/* list of filedescriptor events */
-	struct fd_event {
-		struct event_context *event_ctx;
-		struct fd_event *next, *prev;
-		int fd;
-		uint16_t flags; /* see EVENT_FD_* flags */
-		event_fd_handler_t handler;
-		void *private;
-	} *fd_events;
-
-	/* list of timed events */
-	struct timed_event {
-		struct event_context *event_ctx;
-		struct timed_event *next, *prev;
-		struct timeval next_event;
-		event_timed_handler_t handler;
-		void *private;
-	} *timed_events;
-
-	/* the maximum file descriptor number in fd_events */
-	int maxfd;
-
-	/* information for exiting from the event loop */
-	int exit_code;
-
-	/* this is changed by the destructors for the fd event
-	   type. It is used to detect event destruction by event
-	   handlers, which means the code that is calling the event
-	   handler needs to assume that the linked list is no longer
-	   valid
-	*/
-	uint32_t destruction_count;
-
-#if WITH_EPOLL
-	/* when using epoll this is the handle from epoll_create */
-	int epoll_fd;
-#endif
-};
-
-
-/*
-  destroy an event context
-*/
-static int event_context_destructor(void *ptr)
-{
-#if WITH_EPOLL
-	struct event_context *ev = talloc_get_type(ptr, struct event_context);
-	if (ev->epoll_fd != -1) {
-		close(ev->epoll_fd);
-		ev->epoll_fd = -1;
-	}
-#endif
-	return 0;
-}
-
-/*
-  create a event_context structure. This must be the first events
-  call, and all subsequent calls pass this event_context as the first
-  element. Event handlers also receive this as their first argument.
-*/
-struct event_context *event_context_init(TALLOC_CTX *mem_ctx)
-{
-	struct event_context *ev;
-
-	ev = talloc_zero(mem_ctx, struct event_context);
-	if (!ev) return NULL;
-
-#if WITH_EPOLL
-	ev->epoll_fd = epoll_create(64);
-#endif
-
-	talloc_set_destructor(ev, event_context_destructor);
-
-	return ev;
-}
-
-
-/*
-  recalculate the maxfd
-*/
-static void calc_maxfd(struct event_context *ev)
-{
-	struct fd_event *e;
-	ev->maxfd = 0;
-	for (e=ev->fd_events; e; e=e->next) {
-		if (e->fd > ev->maxfd) {
-			ev->maxfd = e->fd;
-		}
-	}
-}
-
-
-/* to mark the ev->maxfd invalid
- * this means we need to recalculate it
- */
-#define EVENT_INVALID_MAXFD (-1)
-
-
-#if WITH_EPOLL
-/*
-  called when a epoll call fails, and we should fallback
-  to using select
-*/
-static void epoll_fallback_to_select(struct event_context *ev, const char *reason)
-{
-	DEBUG(0,("%s (%s) - falling back to select()\n", reason, strerror(errno)));
-	close(ev->epoll_fd);
-	ev->epoll_fd = -1;
-}
-#endif
-
-
-#if WITH_EPOLL
-/*
-  map from EVENT_FD_* to EPOLLIN/EPOLLOUT
-*/
-static uint32_t epoll_map_flags(uint16_t flags)
-{
-	uint32_t ret = 0;
-	if (flags & EVENT_FD_READ) ret |= EPOLLIN;
-	if (flags & EVENT_FD_WRITE) ret |= EPOLLOUT;
-	return ret;
-}
-#endif
-
-/*
-  destroy an fd_event
-*/
-static int event_fd_destructor(void *ptr)
-{
-	struct fd_event *fde = talloc_get_type(ptr, struct fd_event);
-	struct event_context *ev = fde->event_ctx;
-
-	if (ev->maxfd == fde->fd) {
-		ev->maxfd = EVENT_INVALID_MAXFD;
-	}
-	DLIST_REMOVE(ev->fd_events, fde);
-	ev->destruction_count++;
-#if WITH_EPOLL
-	if (ev->epoll_fd != -1) {
-		struct epoll_event event;
-		ZERO_STRUCT(event);
-		event.events = epoll_map_flags(fde->flags);
-		event.data.ptr = fde;
-		epoll_ctl(ev->epoll_fd, EPOLL_CTL_DEL, fde->fd, &event);
-	}
-#endif
-	return 0;
-}
-
-/*
-  add a fd based event
-  return NULL on failure (memory allocation error)
-*/
-struct fd_event *event_add_fd(struct event_context *ev, TALLOC_CTX *mem_ctx,
-			      int fd, uint16_t flags, event_fd_handler_t handler,
-			      void *private)
-{
-	struct fd_event *e = talloc(ev, struct fd_event);
-	if (!e) return NULL;
-
-	e->event_ctx = ev;
-	e->fd        = fd;
-	e->flags     = flags;
-	e->handler   = handler;
-	e->private   = private;
-
-	DLIST_ADD(ev->fd_events, e);
-
-	if (e->fd > ev->maxfd) {
-		ev->maxfd = e->fd;
-	}
-
-	talloc_set_destructor(e, event_fd_destructor);
-	if (mem_ctx) {
-		talloc_steal(mem_ctx, e);
-	}
-
-#if WITH_EPOLL
-	if (ev->epoll_fd != -1) {
-		struct epoll_event event;
-		ZERO_STRUCT(event);
-		event.events = epoll_map_flags(flags);
-		event.data.ptr = e;
-		if (epoll_ctl(ev->epoll_fd, EPOLL_CTL_ADD, e->fd, &event) != 0) {
-			epoll_fallback_to_select(ev, "EPOLL_CTL_ADD failed");
-		}
-	}
-#endif
-
-	return e;
-}
-
-
-/*
-  return the fd event flags
-*/
-uint16_t event_fd_flags(struct fd_event *fde)
-{
-	return fde?fde->flags:0;
-}
-
-/*
-  set the fd event flags
-*/
-void event_fd_setflags(struct fd_event *fde, uint16_t flags)
-{
-#if WITH_EPOLL
-	struct event_context *ev;
-	if (fde == NULL || 
-	    fde->flags == flags) {
-		return;
-	}
-	ev = fde->event_ctx;
-	if (ev->epoll_fd != -1) {
-		struct epoll_event event;
-		ZERO_STRUCT(event);
-		event.events = epoll_map_flags(flags);
-		event.data.ptr = fde;
-		if (epoll_ctl(ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event) != 0) {
-			epoll_fallback_to_select(ev, "EPOLL_CTL_MOD failed");
-		}
-	}
-#endif
-	if (fde) {
-		fde->flags = flags;
-	}
-}
-
-/*
-  destroy a timed event
-*/
-static int event_timed_destructor(void *ptr)
-{
-	struct timed_event *te = talloc_get_type(ptr, struct timed_event);
-	DLIST_REMOVE(te->event_ctx->timed_events, te);
-	return 0;
-}
-
-/*
-  add a timed event
-  return NULL on failure (memory allocation error)
-*/
-struct timed_event *event_add_timed(struct event_context *ev, TALLOC_CTX *mem_ctx,
-				    struct timeval next_event, 
-				    event_timed_handler_t handler, 
-				    void *private) 
-{
-	struct timed_event *te, *e;
-
-	e = talloc(mem_ctx?mem_ctx:ev, struct timed_event);
-	if (e == NULL) return NULL;
-
-	e->event_ctx  = ev;
-	e->next_event = next_event;
-	e->handler    = handler;
-	e->private    = private;
-
-	/* keep the list ordered */
-	if (ev->timed_events == NULL || 
-	    timeval_compare(&e->next_event, &ev->timed_events->next_event) > 0) {
-		DLIST_ADD(ev->timed_events, e);
-	} else {
-		for (te=ev->timed_events;te && te->next;te=te->next) {
-			if (!timeval_is_zero(&te->next->next_event) &&
-			    timeval_compare(&te->next->next_event, &e->next_event) < 0) {
-				break;
-			}
-		}
-		DLIST_ADD_AFTER(ev->timed_events, e, te);
-	}
-
-	talloc_set_destructor(e, event_timed_destructor);
-
-	return e;
-}
-
-/*
-  a timer has gone off - call it
-*/
-static void event_loop_timer(struct event_context *ev)
-{
-	struct timeval t = timeval_current();
-	struct timed_event *te = ev->timed_events;
-
-	te->next_event = timeval_zero();
-
-	te->handler(ev, te, t, te->private);
-
-	/* note the care taken to prevent referencing a event
-	   that could have been freed by the handler */
-	if (ev->timed_events && timeval_is_zero(&ev->timed_events->next_event)) {
-		talloc_free(ev->timed_events);
-	}
-}
-
-#if WITH_EPOLL
-/*
-  event loop handling using epoll
-*/
-static int event_loop_epoll(struct event_context *ev, struct timeval *tvalp)
-{
-	int ret, i;
-	const int maxevents = 8;
-	struct epoll_event events[maxevents];
-	uint32_t destruction_count = ev->destruction_count;
-	int timeout = -1;
-
-	if (tvalp) {
-		timeout = (tvalp->tv_usec / 1000) + (tvalp->tv_sec*1000);
-	}
-
-	ret = epoll_wait(ev->epoll_fd, events, maxevents, timeout);
-
-	if (ret == -1 && errno != EINTR) {
-		epoll_fallback_to_select(ev, "epoll_wait() failed");
-		return -1;
-	}
-
-	if (ret == 0 && tvalp) {
-		event_loop_timer(ev);
-		return 0;
-	}
-
-	for (i=0;i<ret;i++) {
-		struct fd_event *fde = talloc_get_type(events[i].data.ptr, 
-						       struct fd_event);
-		uint16_t flags = 0;
-
-		if (fde == NULL) {
-			epoll_fallback_to_select(ev, "epoll_wait() gave bad data");
-			return -1;
-		}
-		if (events[i].events & (EPOLLIN|EPOLLHUP|EPOLLERR)) 
-			flags |= EVENT_FD_READ;
-		if (events[i].events & EPOLLOUT) flags |= EVENT_FD_WRITE;
-		if (flags) {
-			fde->handler(ev, fde, flags, fde->private);
-			if (destruction_count != ev->destruction_count) {
-				break;
-			}
-		}
-	}
-
-	return 0;
-}		
-#endif
-
-/*
-  event loop handling using select()
-*/
-static int event_loop_select(struct event_context *ev, struct timeval *tvalp)
-{
-	fd_set r_fds, w_fds;
-	int selrtn;
-	uint32_t destruction_count = ev->destruction_count;
-	struct fd_event *fe;
-
-	/* we maybe need to recalculate the maxfd */
-	if (ev->maxfd == EVENT_INVALID_MAXFD) {
-		calc_maxfd(ev);
-	}
-		
-	FD_ZERO(&r_fds);
-	FD_ZERO(&w_fds);
-
-	/* setup any fd events */
-	for (fe=ev->fd_events; fe; ) {
-		struct fd_event *next = fe->next;
-		if (fe->flags & EVENT_FD_READ) {
-			FD_SET(fe->fd, &r_fds);
-		}
-		if (fe->flags & EVENT_FD_WRITE) {
-			FD_SET(fe->fd, &w_fds);
-		}
-		fe = next;
-	}
-
-	selrtn = select(ev->maxfd+1, &r_fds, &w_fds, NULL, tvalp);
-		
-	if (selrtn == -1 && errno == EBADF) {
-		/* the socket is dead! this should never
-		   happen as the socket should have first been
-		   made readable and that should have removed
-		   the event, so this must be a bug. This is a
-		   fatal error. */
-		DEBUG(0,("ERROR: EBADF on event_loop_once\n"));
-		ev->exit_code = EBADF;
-		return -1;
-	}
-
-	if (selrtn == 0 && tvalp) {
-		event_loop_timer(ev);
-		return 0;
-	}
-
-	if (selrtn > 0) {
-		/* at least one file descriptor is ready - check
-		   which ones and call the handler, being careful to allow
-		   the handler to remove itself when called */
-		for (fe=ev->fd_events; fe; fe=fe->next) {
-			uint16_t flags = 0;
-			if (FD_ISSET(fe->fd, &r_fds)) flags |= EVENT_FD_READ;
-			if (FD_ISSET(fe->fd, &w_fds)) flags |= EVENT_FD_WRITE;
-			if (flags) {
-				fe->handler(ev, fe, flags, fe->private);
-				if (destruction_count != ev->destruction_count) {
-					break;
-				}
-			}
-		}
-	}
-
-	return 0;
-}		
-
-/*
-  do a single event loop using the events defined in ev 
-*/
-int event_loop_once(struct event_context *ev)
-{
-	struct timeval tval, *tvalp;
-
-	tvalp = NULL;
-		
-	/* work out the right timeout for all timed events */
-	if (ev->timed_events) {
-		struct timeval t = timeval_current();
-		tval = timeval_diff(&ev->timed_events->next_event, &t);
-		tvalp = &tval;
-		if (timeval_is_zero(tvalp)) {
-			event_loop_timer(ev);
-			return 0;
-		}
-	}
-
-#if WITH_EPOLL
-	if (ev->epoll_fd != -1) {
-		if (event_loop_epoll(ev, tvalp) == 0) {
-			return 0;
-		}
-	}
-#endif
-
-	return event_loop_select(ev, tvalp);
-}
-
-/*
-  go into an event loop using the events defined in ev this function
-  will return with the specified code if one of the handlers calls
-  event_loop_exit()
-
-  also return (with code 0) if all fd events are removed
-*/
-int event_loop_wait(struct event_context *ev)
-{
-	ev->exit_code = 0;
-	ev->maxfd = EVENT_INVALID_MAXFD;
-
-	while (ev->fd_events && ev->exit_code == 0) {
-		if (event_loop_once(ev) != 0) {
-			break;
-		}
-	}
-
-	return ev->exit_code;
-}