tevent: Remove the previous "standard" tevent backend implementation.

This was a horrible hybrid of duplicated epoll and select()
code.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Thu Feb 14 22:40:30 CET 2013 on sn-devel-104

1 files changed, 1 insertions, 556 deletions

diff --git a/lib/tevent/tevent_standard.c b/lib/tevent/tevent_standard.c
index 0c72226558..d7a5bd7b18 100644
--- a/lib/tevent/tevent_standard.c
+++ b/lib/tevent/tevent_standard.c
@@ -1,8 +1,7 @@
 /* 
    Unix SMB/CIFS implementation.
    main select loop and event handling
-   Copyright (C) Andrew Tridgell	2003-2005
-   Copyright (C) Stefan Metzmacher      2005-2013
+   Copyright (C) Stefan Metzmacher      2013
    Copyright (C) Jeremy Allison         2013
 
      ** NOTE! The following LGPL license applies to the tevent
@@ -37,560 +36,6 @@
 #include "tevent_util.h"
 #include "tevent_internal.h"
 
-#if 0
-struct std_event_context {
-	/* a pointer back to the generic event_context */
-	struct tevent_context *ev;
-
-	/* the maximum file descriptor number in fd_events */
-	int maxfd;
-
-	/* information for exiting from the event loop */
-	int exit_code;
-
-	/* when using epoll this is the handle from epoll_create */
-	int epoll_fd;
-
-	/* our pid at the time the epoll_fd was created */
-	pid_t pid;
-};
-
-/* use epoll if it is available */
-#if HAVE_EPOLL
-/*
-  called when a epoll call fails, and we should fallback
-  to using select
-*/
-static void epoll_fallback_to_select(struct std_event_context *std_ev, const char *reason)
-{
-	tevent_debug(std_ev->ev, TEVENT_DEBUG_FATAL,
-		     "%s (%s) - falling back to select()\n",
-		     reason, strerror(errno));
-	close(std_ev->epoll_fd);
-	std_ev->epoll_fd = -1;
-	talloc_set_destructor(std_ev, NULL);
-}
-
-/*
-  map from TEVENT_FD_* to EPOLLIN/EPOLLOUT
-*/
-static uint32_t epoll_map_flags(uint16_t flags)
-{
-	uint32_t ret = 0;
-	if (flags & TEVENT_FD_READ) ret |= (EPOLLIN | EPOLLERR | EPOLLHUP);
-	if (flags & TEVENT_FD_WRITE) ret |= (EPOLLOUT | EPOLLERR | EPOLLHUP);
-	return ret;
-}
-
-/*
- free the epoll fd
-*/
-static int epoll_ctx_destructor(struct std_event_context *std_ev)
-{
-	if (std_ev->epoll_fd != -1) {
-		close(std_ev->epoll_fd);
-	}
-	std_ev->epoll_fd = -1;
-	return 0;
-}
-
-/*
- init the epoll fd
-*/
-static void epoll_init_ctx(struct std_event_context *std_ev)
-{
-	std_ev->epoll_fd = epoll_create(64);
-	if (std_ev->epoll_fd == -1) {
-		tevent_debug(std_ev->ev, TEVENT_DEBUG_FATAL,
-			     "Failed to create epoll handle.\n");
-		return;
-	}
-
-	if (!ev_set_close_on_exec(std_ev->epoll_fd)) {
-		tevent_debug(std_ev->ev, TEVENT_DEBUG_WARNING,
-			     "Failed to set close-on-exec, file descriptor may be leaked to children.\n");
-	}
-
-	std_ev->pid = getpid();
-	talloc_set_destructor(std_ev, epoll_ctx_destructor);
-}
-
-static void epoll_add_event(struct std_event_context *std_ev, struct tevent_fd *fde);
-
-/*
-  reopen the epoll handle when our pid changes
-  see http://junkcode.samba.org/ftp/unpacked/junkcode/epoll_fork.c for an 
-  demonstration of why this is needed
- */
-static void epoll_check_reopen(struct std_event_context *std_ev)
-{
-	struct tevent_fd *fde;
-
-	if (std_ev->pid == getpid()) {
-		return;
-	}
-
-	close(std_ev->epoll_fd);
-	std_ev->epoll_fd = epoll_create(64);
-	if (std_ev->epoll_fd == -1) {
-		tevent_debug(std_ev->ev, TEVENT_DEBUG_FATAL,
-			     "Failed to recreate epoll handle after fork\n");
-		return;
-	}
-
-	if (!ev_set_close_on_exec(std_ev->epoll_fd)) {
-		tevent_debug(std_ev->ev, TEVENT_DEBUG_WARNING,
-			     "Failed to set close-on-exec, file descriptor may be leaked to children.\n");
-	}
-
-	std_ev->pid = getpid();
-	for (fde=std_ev->ev->fd_events;fde;fde=fde->next) {
-		epoll_add_event(std_ev, fde);
-	}
-}
-
-#define EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT	(1<<0)
-#define EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR	(1<<1)
-#define EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR	(1<<2)
-
-/*
- add the epoll event to the given fd_event
-*/
-static void epoll_add_event(struct std_event_context *std_ev, struct tevent_fd *fde)
-{
-	struct epoll_event event;
-	if (std_ev->epoll_fd == -1) return;
-
-	fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
-	/* if we don't want events yet, don't add an epoll_event */
-	if (fde->flags == 0) return;
-
-	ZERO_STRUCT(event);
-	event.events = epoll_map_flags(fde->flags);
-	event.data.ptr = fde;
-	if (epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_ADD, fde->fd, &event) != 0) {
-		epoll_fallback_to_select(std_ev, "EPOLL_CTL_ADD failed");
-	}
-	fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
-
-	/* only if we want to read we want to tell the event handler about errors */
-	if (fde->flags & TEVENT_FD_READ) {
-		fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-	}
-}
-
-/*
- delete the epoll event for given fd_event
-*/
-static void epoll_del_event(struct std_event_context *std_ev, struct tevent_fd *fde)
-{
-	struct epoll_event event;
-	if (std_ev->epoll_fd == -1) return;
-
-	fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
-	/* if there's no epoll_event, we don't need to delete it */
-	if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT)) return;
-
-	ZERO_STRUCT(event);
-	event.events = epoll_map_flags(fde->flags);
-	event.data.ptr = fde;
-	epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_DEL, fde->fd, &event);
-	fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT;
-}
-
-/*
- change the epoll event to the given fd_event
-*/
-static void epoll_mod_event(struct std_event_context *std_ev, struct tevent_fd *fde)
-{
-	struct epoll_event event;
-	if (std_ev->epoll_fd == -1) return;
-
-	fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
-	ZERO_STRUCT(event);
-	event.events = epoll_map_flags(fde->flags);
-	event.data.ptr = fde;
-	if (epoll_ctl(std_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event) != 0) {
-		epoll_fallback_to_select(std_ev, "EPOLL_CTL_MOD failed");
-	}
-
-	/* only if we want to read we want to tell the event handler about errors */
-	if (fde->flags & TEVENT_FD_READ) {
-		fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-	}
-}
-
-static void epoll_change_event(struct std_event_context *std_ev, struct tevent_fd *fde)
-{
-	bool got_error = (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR);
-	bool want_read = (fde->flags & TEVENT_FD_READ);
-	bool want_write= (fde->flags & TEVENT_FD_WRITE);
-
-	if (std_ev->epoll_fd == -1) return;
-
-	fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR;
-
-	/* there's already an event */
-	if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT) {
-		if (want_read || (want_write && !got_error)) {
-			epoll_mod_event(std_ev, fde);
-			return;
-		}
-		/* 
-		 * if we want to match the select behavior, we need to remove the epoll_event
-		 * when the caller isn't interested in events.
-		 *
-		 * this is because epoll reports EPOLLERR and EPOLLHUP, even without asking for them
-		 */
-		epoll_del_event(std_ev, fde);
-		return;
-	}
-
-	/* there's no epoll_event attached to the fde */
-	if (want_read || (want_write && !got_error)) {
-		epoll_add_event(std_ev, fde);
-		return;
-	}
-}
-
-/*
-  event loop handling using epoll
-*/
-static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tvalp)
-{
-	int ret, i;
-#define MAXEVENTS 1
-	struct epoll_event events[MAXEVENTS];
-	int timeout = -1;
-
-	if (std_ev->epoll_fd == -1) return -1;
-
-	if (tvalp) {
-		/* it's better to trigger timed events a bit later than to early */
-		timeout = ((tvalp->tv_usec+999) / 1000) + (tvalp->tv_sec*1000);
-	}
-
-	if (std_ev->ev->signal_events &&
-	    tevent_common_check_signal(std_ev->ev)) {
-		return 0;
-	}
-
-	tevent_trace_point_callback(std_ev->ev, TEVENT_TRACE_BEFORE_WAIT);
-	ret = epoll_wait(std_ev->epoll_fd, events, MAXEVENTS, timeout);
-	tevent_trace_point_callback(std_ev->ev, TEVENT_TRACE_AFTER_WAIT);
-
-	if (ret == -1 && errno == EINTR && std_ev->ev->signal_events) {
-		if (tevent_common_check_signal(std_ev->ev)) {
-			return 0;
-		}
-	}
-
-	if (ret == -1 && errno != EINTR) {
-		epoll_fallback_to_select(std_ev, "epoll_wait() failed");
-		return -1;
-	}
-
-	if (ret == 0 && tvalp) {
-		/* we don't care about a possible delay here */
-		tevent_common_loop_timer_delay(std_ev->ev);
-		return 0;
-	}
-
-	for (i=0;i<ret;i++) {
-		struct tevent_fd *fde = talloc_get_type(events[i].data.ptr, 
-						       struct tevent_fd);
-		uint16_t flags = 0;
-
-		if (fde == NULL) {
-			epoll_fallback_to_select(std_ev, "epoll_wait() gave bad data");
-			return -1;
-		}
-		if (events[i].events & (EPOLLHUP|EPOLLERR)) {
-			fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR;
-			/*
-			 * if we only wait for TEVENT_FD_WRITE, we should not tell the
-			 * event handler about it, and remove the epoll_event,
-			 * as we only report errors when waiting for read events,
-			 * to match the select() behavior
-			 */
-			if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR)) {
-				epoll_del_event(std_ev, fde);
-				continue;
-			}
-			flags |= TEVENT_FD_READ;
-		}
-		if (events[i].events & EPOLLIN) flags |= TEVENT_FD_READ;
-		if (events[i].events & EPOLLOUT) flags |= TEVENT_FD_WRITE;
-		if (flags) {
-			fde->handler(std_ev->ev, fde, flags, fde->private_data);
-			break;
-		}
-	}
-
-	return 0;
-}
-#else
-#define epoll_init_ctx(std_ev) 
-#define epoll_add_event(std_ev,fde)
-#define epoll_del_event(std_ev,fde)
-#define epoll_change_event(std_ev,fde)
-#define epoll_event_loop(std_ev,tvalp) (-1)
-#define epoll_check_reopen(std_ev)
-#endif
-
-/*
-  create a std_event_context structure.
-*/
-static int std_event_context_init(struct tevent_context *ev)
-{
-	struct std_event_context *std_ev;
-
-	/*
-	 * We might be called during tevent_re_initialise()
-	 * which means we need to free our old additional_data.
-	 */
-	TALLOC_FREE(ev->additional_data);
-
-	std_ev = talloc_zero(ev, struct std_event_context);
-	if (!std_ev) return -1;
-	std_ev->ev = ev;
-	std_ev->epoll_fd = -1;
-
-	epoll_init_ctx(std_ev);
-
-	ev->additional_data = std_ev;
-	return 0;
-}
-
-/*
-  recalculate the maxfd
-*/
-static void calc_maxfd(struct std_event_context *std_ev)
-{
-	struct tevent_fd *fde;
-
-	std_ev->maxfd = 0;
-	for (fde = std_ev->ev->fd_events; fde; fde = fde->next) {
-		if (fde->fd > std_ev->maxfd) {
-			std_ev->maxfd = fde->fd;
-		}
-	}
-}
-
-
-/* to mark the ev->maxfd invalid
- * this means we need to recalculate it
- */
-#define EVENT_INVALID_MAXFD (-1)
-
-/*
-  destroy an fd_event
-*/
-static int std_event_fd_destructor(struct tevent_fd *fde)
-{
-	struct tevent_context *ev = fde->event_ctx;
-	struct std_event_context *std_ev = NULL;
-
-	if (ev) {
-		std_ev = talloc_get_type(ev->additional_data,
-					 struct std_event_context);
-
-		epoll_check_reopen(std_ev);
-
-		if (std_ev->maxfd == fde->fd) {
-			std_ev->maxfd = EVENT_INVALID_MAXFD;
-		}
-
-		epoll_del_event(std_ev, fde);
-	}
-
-	return tevent_common_fd_destructor(fde);
-}
-
-/*
-  add a fd based event
-  return NULL on failure (memory allocation error)
-*/
-static struct tevent_fd *std_event_add_fd(struct tevent_context *ev, TALLOC_CTX *mem_ctx,
-					  int fd, uint16_t flags,
-					  tevent_fd_handler_t handler,
-					  void *private_data,
-					  const char *handler_name,
-					  const char *location)
-{
-	struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
-							   struct std_event_context);
-	struct tevent_fd *fde;
-
-	epoll_check_reopen(std_ev);
-
-	fde = tevent_common_add_fd(ev, mem_ctx, fd, flags,
-				   handler, private_data,
-				   handler_name, location);
-	if (!fde) return NULL;
-
-	if ((std_ev->maxfd != EVENT_INVALID_MAXFD)
-	    && (fde->fd > std_ev->maxfd)) {
-		std_ev->maxfd = fde->fd;
-	}
-	talloc_set_destructor(fde, std_event_fd_destructor);
-
-	epoll_add_event(std_ev, fde);
-
-	return fde;
-}
-
-/*
-  set the fd event flags
-*/
-static void std_event_set_fd_flags(struct tevent_fd *fde, uint16_t flags)
-{
-	struct tevent_context *ev;
-	struct std_event_context *std_ev;
-
-	if (fde->flags == flags) return;
-
-	ev = fde->event_ctx;
-	std_ev = talloc_get_type(ev->additional_data, struct std_event_context);
-
-	fde->flags = flags;
-
-	epoll_check_reopen(std_ev);
-
-	epoll_change_event(std_ev, fde);
-}
-
-/*
-  event loop handling using select()
-*/
-static int std_event_loop_select(struct std_event_context *std_ev, struct timeval *tvalp)
-{
-	fd_set r_fds, w_fds;
-	struct tevent_fd *fde;
-	int selrtn;
-
-	/* we maybe need to recalculate the maxfd */
-	if (std_ev->maxfd == EVENT_INVALID_MAXFD) {
-		calc_maxfd(std_ev);
-	}
-
-	FD_ZERO(&r_fds);
-	FD_ZERO(&w_fds);
-
-	/* setup any fd events */
-	for (fde = std_ev->ev->fd_events; fde; fde = fde->next) {
-		if (fde->fd < 0 || fde->fd >= FD_SETSIZE) {
-			std_ev->exit_code = EBADF;
-			return -1;
-		}
-		if (fde->flags & TEVENT_FD_READ) {
-			FD_SET(fde->fd, &r_fds);
-		}
-		if (fde->flags & TEVENT_FD_WRITE) {
-			FD_SET(fde->fd, &w_fds);
-		}
-	}
-
-	if (std_ev->ev->signal_events &&
-	    tevent_common_check_signal(std_ev->ev)) {
-		return 0;
-	}
-
-	selrtn = select(std_ev->maxfd+1, &r_fds, &w_fds, NULL, tvalp);
-
-	if (selrtn == -1 && errno == EINTR && 
-	    std_ev->ev->signal_events) {
-		tevent_common_check_signal(std_ev->ev);
-		return 0;
-	}
-
-	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. */
-		tevent_debug(std_ev->ev, TEVENT_DEBUG_FATAL,
-			     "ERROR: EBADF on std_event_loop_once\n");
-		std_ev->exit_code = EBADF;
-		return -1;
-	}
-
-	if (selrtn == 0 && tvalp) {
-		/* we don't care about a possible delay here */
-		tevent_common_loop_timer_delay(std_ev->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 (fde = std_ev->ev->fd_events; fde; fde = fde->next) {
-			uint16_t flags = 0;
-
-			if (FD_ISSET(fde->fd, &r_fds)) flags |= TEVENT_FD_READ;
-			if (FD_ISSET(fde->fd, &w_fds)) flags |= TEVENT_FD_WRITE;
-			if (flags & fde->flags) {
-				fde->handler(std_ev->ev, fde, flags, fde->private_data);
-				break;
-			}
-		}
-	}
-
-	return 0;
-}		
-
-/*
-  do a single event loop using the events defined in ev 
-*/
-static int std_event_loop_once(struct tevent_context *ev, const char *location)
-{
-	struct std_event_context *std_ev = talloc_get_type(ev->additional_data,
-		 					   struct std_event_context);
-	struct timeval tval;
-
-	if (ev->signal_events &&
-	    tevent_common_check_signal(ev)) {
-		return 0;
-	}
-
-	if (ev->immediate_events &&
-	    tevent_common_loop_immediate(ev)) {
-		return 0;
-	}
-
-	tval = tevent_common_loop_timer_delay(ev);
-	if (tevent_timeval_is_zero(&tval)) {
-		return 0;
-	}
-
-	epoll_check_reopen(std_ev);
-
-	if (epoll_event_loop(std_ev, &tval) == 0) {
-		return 0;
-	}
-
-	return std_event_loop_select(std_ev, &tval);
-}
-
-static const struct tevent_ops std_event_ops = {
-	.context_init		= std_event_context_init,
-	.add_fd			= std_event_add_fd,
-	.set_fd_close_fn	= tevent_common_fd_set_close_fn,
-	.get_fd_flags		= tevent_common_fd_get_flags,
-	.set_fd_flags		= std_event_set_fd_flags,
-	.add_timer		= tevent_common_add_timer,
-	.schedule_immediate	= tevent_common_schedule_immediate,
-	.add_signal		= tevent_common_add_signal,
-	.loop_once		= std_event_loop_once,
-	.loop_wait		= tevent_common_loop_wait,
-};
-#endif
-
 struct std_event_glue {
 	const struct tevent_ops *epoll_ops;
 	const struct tevent_ops *poll_ops;