check in v3.8.1 source

apps/nc/atomicio.c

@@ -0,0 +1,67 @@
+/* $OpenBSD: atomicio.c,v 1.11 2012/12/04 02:24:47 deraadt Exp $ */
+/*
+ * Copyright (c) 2006 Damien Miller. All rights reserved.
+ * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
+ * Copyright (c) 1995,1999 Theo de Raadt.  All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <errno.h>
+#include <poll.h>
+#include <unistd.h>
+
+#include "atomicio.h"
+
+/*
+ * ensure all of data on socket comes through. f==read || f==vwrite
+ */
+size_t
+atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
+{
+	char *s = _s;
+	size_t pos = 0;
+	ssize_t res;
+	struct pollfd pfd;
+
+	pfd.fd = fd;
+	pfd.events = f == read ? POLLIN : POLLOUT;
+	while (n > pos) {
+		res = (f) (fd, s + pos, n - pos);
+		switch (res) {
+		case -1:
+			if (errno == EINTR)
+				continue;
+			if ((errno == EAGAIN) || (errno == ENOBUFS)) {
+				(void)poll(&pfd, 1, -1);
+				continue;
+			}
+			return 0;
+		case 0:
+			errno = EPIPE;
+			return pos;
+		default:
+			pos += (size_t)res;
+		}
+	}
+	return (pos);
+}