From: Dmitry Antipov <dantipov@cloudlinux.com>
Date: Fri, 7 Apr 2023 11:47:15 +0000 (+0300)
Subject: tevent: rely on epoll_create1() for epoll interface
X-Git-Tag: tevent-0.15.0~22
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a665d44f22c1fea4fd9104e4e3e45ee9b6cd68cd;p=thirdparty%2Fsamba.git

tevent: rely on epoll_create1() for epoll interface

Prefer epoll_create1(2) over epoll_create(2) and
always require the former to use epoll(7) interface,
thus saving extra fcntl(2) call to set FD_CLOEXEC.

Signed-off-by: Dmitry Antipov <dantipov@cloudlinux.com>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
---

diff --git a/lib/tevent/tevent_epoll.c b/lib/tevent/tevent_epoll.c
index 1f1f47b2b21..ac8340118e9 100644
--- a/lib/tevent/tevent_epoll.c
+++ b/lib/tevent/tevent_epoll.c
@@ -36,7 +36,7 @@ struct epoll_event_context {
 	/* a pointer back to the generic event_context */
 	struct tevent_context *ev;
 
-	/* when using epoll this is the handle from epoll_create */
+	/* when using epoll this is the handle from epoll_create1(2) */
 	int epoll_fd;
 
 	pid_t pid;
@@ -53,11 +53,11 @@ struct epoll_event_context {
 
 #ifdef TEST_PANIC_FALLBACK
 
-static int epoll_create_panic_fallback(struct epoll_event_context *epoll_ev,
-				       int size)
+static int epoll_create1_panic_fallback(struct epoll_event_context *epoll_ev,
+					int flags)
 {
 	if (epoll_ev->panic_fallback == NULL) {
-		return epoll_create(size);
+		return epoll_create1(flags);
 	}
 
 	/* 50% of the time, fail... */
@@ -66,7 +66,7 @@ static int epoll_create_panic_fallback(struct epoll_event_context *epoll_ev,
 		return -1;
 	}
 
-	return epoll_create(size);
+	return epoll_create1(flags);
 }
 
 static int epoll_ctl_panic_fallback(struct epoll_event_context *epoll_ev,
@@ -105,8 +105,8 @@ static int epoll_wait_panic_fallback(struct epoll_event_context *epoll_ev,
 	return epoll_wait(epfd, events, maxevents, timeout);
 }
 
-#define epoll_create(_size) \
-	epoll_create_panic_fallback(epoll_ev, _size)
+#define epoll_create1(_flags) \
+	epoll_create1_panic_fallback(epoll_ev, _flags)
 #define epoll_ctl(_epfd, _op, _fd, _event) \
 	epoll_ctl_panic_fallback(epoll_ev,_epfd, _op, _fd, _event)
 #define epoll_wait(_epfd, _events, _maxevents, _timeout) \
@@ -194,18 +194,14 @@ static int epoll_ctx_destructor(struct epoll_event_context *epoll_ev)
 */
 static int epoll_init_ctx(struct epoll_event_context *epoll_ev)
 {
-	epoll_ev->epoll_fd = epoll_create(64);
+	epoll_ev->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
 	if (epoll_ev->epoll_fd == -1) {
 		tevent_debug(epoll_ev->ev, TEVENT_DEBUG_FATAL,
-			     "Failed to create epoll handle.\n");
+			     "Failed to create epoll handle (%s).\n",
+			     strerror(errno));
 		return -1;
 	}
 
-	if (!ev_set_close_on_exec(epoll_ev->epoll_fd)) {
-		tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
-			     "Failed to set close-on-exec, file descriptor may be leaked to children.\n");
-	}
-
 	epoll_ev->pid = tevent_cached_getpid();
 	talloc_set_destructor(epoll_ev, epoll_ctx_destructor);
 
@@ -231,17 +227,12 @@ static void epoll_check_reopen(struct epoll_event_context *epoll_ev)
 	}
 
 	close(epoll_ev->epoll_fd);
-	epoll_ev->epoll_fd = epoll_create(64);
+	epoll_ev->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
 	if (epoll_ev->epoll_fd == -1) {
 		epoll_panic(epoll_ev, "epoll_create() failed", false);
 		return;
 	}
 
-	if (!ev_set_close_on_exec(epoll_ev->epoll_fd)) {
-		tevent_debug(epoll_ev->ev, TEVENT_DEBUG_WARNING,
-			     "Failed to set close-on-exec, file descriptor may be leaked to children.\n");
-	}
-
 	epoll_ev->pid = pid;
 	epoll_ev->panic_state = &panic_triggered;
 	for (fde=epoll_ev->ev->fd_events;fde;fde=fde->next) {
diff --git a/lib/tevent/wscript b/lib/tevent/wscript
index 0f6e92f93e8..bed4b6a80af 100644
--- a/lib/tevent/wscript
+++ b/lib/tevent/wscript
@@ -51,7 +51,7 @@ def configure(conf):
                 conf.CHECK_BUNDLED_SYSTEM_PYTHON('pytevent', 'tevent', minversion=VERSION):
                 conf.define('USING_SYSTEM_PYTEVENT', 1)
 
-    if conf.CHECK_FUNCS('epoll_create', headers='sys/epoll.h'):
+    if conf.CHECK_FUNCS('epoll_create1', headers='sys/epoll.h'):
         conf.DEFINE('HAVE_EPOLL', 1)
 
     tevent_num_signals = 64