From a91920a8ffe836346fd66ddf7971cda4f19071c6 Mon Sep 17 00:00:00 2001
From: Max Kellermann <mk@cm4all.com>
Date: Thu, 11 Jan 2024 17:06:57 +0100
Subject: [PATCH] net/SocketDescriptor: pass span<byte> to Read()/Write()

---
 src/net/SocketDescriptor.cxx | 15 +++++++++------
 src/net/SocketDescriptor.hxx |  8 ++++----
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/net/SocketDescriptor.cxx b/src/net/SocketDescriptor.cxx
index b3398ec90..8cdce6f6e 100644
--- a/src/net/SocketDescriptor.cxx
+++ b/src/net/SocketDescriptor.cxx
@@ -492,8 +492,8 @@ SocketDescriptor::WaitWritable(int timeout_ms) const noexcept
 #endif
 
 ssize_t
-SocketDescriptor::Read(void *buffer, std::size_t length,
-		       StaticSocketAddress &address) const noexcept
+SocketDescriptor::ReadNoWait(std::span<std::byte> dest,
+			     StaticSocketAddress &address) const noexcept
 {
 	int flags = 0;
 #ifndef _WIN32
@@ -501,7 +501,9 @@ SocketDescriptor::Read(void *buffer, std::size_t length,
 #endif
 
 	socklen_t addrlen = address.GetCapacity();
-	ssize_t nbytes = ::recvfrom(Get(), (char *)buffer, length, flags,
+	ssize_t nbytes = ::recvfrom(Get(),
+				    reinterpret_cast<char *>(dest.data()),
+				    dest.size(), flags,
 				    address, &addrlen);
 	if (nbytes > 0)
 		address.SetSize(addrlen);
@@ -510,8 +512,8 @@ SocketDescriptor::Read(void *buffer, std::size_t length,
 }
 
 ssize_t
-SocketDescriptor::Write(const void *buffer, std::size_t length,
-			SocketAddress address) const noexcept
+SocketDescriptor::WriteNoWait(std::span<const std::byte> src,
+			      SocketAddress address) const noexcept
 {
 	int flags = 0;
 #ifndef _WIN32
@@ -521,7 +523,8 @@ SocketDescriptor::Write(const void *buffer, std::size_t length,
 	flags |= MSG_NOSIGNAL;
 #endif
 
-	return ::sendto(Get(), (const char *)buffer, length, flags,
+	return ::sendto(Get(), reinterpret_cast<const char *>(src.data()),
+			src.size(), flags,
 			address.GetAddress(), address.GetSize());
 }
 
diff --git a/src/net/SocketDescriptor.hxx b/src/net/SocketDescriptor.hxx
index 412f3f4ae..03a994bb0 100644
--- a/src/net/SocketDescriptor.hxx
+++ b/src/net/SocketDescriptor.hxx
@@ -351,15 +351,15 @@ public:
 	 * Receive a datagram and return the source address.
 	 */
 	[[nodiscard]]
-	ssize_t Read(void *buffer, std::size_t length,
-		     StaticSocketAddress &address) const noexcept;
+	ssize_t ReadNoWait(std::span<std::byte> dest,
+			   StaticSocketAddress &address) const noexcept;
 
 	/**
 	 * Send a datagram to the specified address.
 	 */
 	[[nodiscard]]
-	ssize_t Write(const void *buffer, std::size_t length,
-		      SocketAddress address) const noexcept;
+	ssize_t WriteNoWait(std::span<const std::byte> src,
+			    SocketAddress address) const noexcept;
 
 #ifndef _WIN32
 	void Shutdown() const noexcept;