From: Volker Lendecke <vl@samba.org>
Date: Mon, 22 Dec 2008 21:17:28 +0000 (+0100)
Subject: Add write_data_iov
X-Git-Tag: samba-3.3.0~127
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee03d50f5b40d6d50c99acac0cba62c7faa2f42a;p=thirdparty%2Fsamba.git

Add write_data_iov
(cherry picked from commit efd5aa6a75c68c6fa48eaa928e652e3cacf0e18e)
---

diff --git a/source/include/proto.h b/source/include/proto.h
index d29a108ac48..db47e2fbdba 100644
--- a/source/include/proto.h
+++ b/source/include/proto.h
@@ -1576,6 +1576,7 @@ NTSTATUS read_socket_with_timeout(int fd, char *buf,
 				  size_t *size_ret);
 NTSTATUS read_data(int fd, char *buffer, size_t N);
 ssize_t write_data(int fd, const char *buffer, size_t N);
+ssize_t write_data_iov(int fd, const struct iovec *orig_iov, int iovcnt);
 bool send_keepalive(int client);
 NTSTATUS read_smb_length_return_keepalive(int fd, char *inbuf,
 					  unsigned int timeout,
diff --git a/source/lib/util_sock.c b/source/lib/util_sock.c
index e64b0036bfd..c0e947b06cb 100644
--- a/source/lib/util_sock.c
+++ b/source/lib/util_sock.c
@@ -1036,6 +1036,75 @@ NTSTATUS read_data(int fd, char *buffer, size_t N)
 	return read_socket_with_timeout(fd, buffer, N, N, 0, NULL);
 }
 
+/****************************************************************************
+ Write all data from an iov array
+****************************************************************************/
+
+ssize_t write_data_iov(int fd, const struct iovec *orig_iov, int iovcnt)
+{
+	int i;
+	size_t to_send;
+	ssize_t thistime;
+	size_t sent;
+	struct iovec *iov_copy, *iov;
+
+	to_send = 0;
+	for (i=0; i<iovcnt; i++) {
+		to_send += orig_iov[i].iov_len;
+	}
+
+	thistime = sys_writev(fd, orig_iov, iovcnt);
+	if ((thistime <= 0) || (thistime == to_send)) {
+		return thistime;
+	}
+	sent = thistime;
+
+	/*
+	 * We could not send everything in one call. Make a copy of iov that
+	 * we can mess with. We keep a copy of the array start in iov_copy for
+	 * the TALLOC_FREE, because we're going to modify iov later on,
+	 * discarding elements.
+	 */
+
+	iov_copy = (struct iovec *)TALLOC_MEMDUP(
+		talloc_tos(), orig_iov, sizeof(struct iovec) * iovcnt);
+
+	if (iov_copy == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+	iov = iov_copy;
+
+	while (sent < to_send) {
+		/*
+		 * We have to discard "thistime" bytes from the beginning
+		 * iov array, "thistime" contains the number of bytes sent
+		 * via writev last.
+		 */
+		while (thistime > 0) {
+			if (thistime < iov[0].iov_len) {
+				char *new_base =
+					(char *)iov[0].iov_base + thistime;
+				iov[0].iov_base = new_base;
+				iov[0].iov_len -= thistime;
+				break;
+			}
+			thistime -= iov[0].iov_len;
+			iov += 1;
+			iovcnt -= 1;
+		}
+
+		thistime = sys_writev(fd, iov, iovcnt);
+		if (thistime <= 0) {
+			break;
+		}
+		sent += thistime;
+	}
+
+	TALLOC_FREE(iov_copy);
+	return sent;
+}
+
 /****************************************************************************
  Write data to a fd.
 ****************************************************************************/