From 6dce8dcaa55bfcf42fb50f756ac423b58fb0dde2 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@ionos.com>
Date: Tue, 12 Nov 2024 08:48:27 +0100
Subject: [PATCH] io/FileDescriptor: add readv()/writev() wrappers

---
 src/io/FileDescriptor.cxx | 13 +++++++++++++
 src/io/FileDescriptor.hxx | 13 +++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/src/io/FileDescriptor.cxx b/src/io/FileDescriptor.cxx
index 5d326b1a0..031579cc4 100644
--- a/src/io/FileDescriptor.cxx
+++ b/src/io/FileDescriptor.cxx
@@ -13,6 +13,7 @@
 
 #ifndef _WIN32
 #include <poll.h>
+#include <sys/uio.h> // for struct iovec
 #endif
 
 #ifndef O_NOCTTY
@@ -295,6 +296,18 @@ FileDescriptor::FullWrite(std::span<const std::byte> src) const
 
 #ifndef _WIN32
 
+ssize_t
+FileDescriptor::Read(std::span<const struct iovec> v) const noexcept
+{
+	return readv(fd, v.data(), v.size());
+}
+
+ssize_t
+FileDescriptor::Write(std::span<const struct iovec> v) const noexcept
+{
+	return writev(fd, v.data(), v.size());
+}
+
 int
 FileDescriptor::Poll(short events, int timeout) const noexcept
 {
diff --git a/src/io/FileDescriptor.hxx b/src/io/FileDescriptor.hxx
index 458cd8168..6bb9c45c3 100644
--- a/src/io/FileDescriptor.hxx
+++ b/src/io/FileDescriptor.hxx
@@ -14,6 +14,7 @@
 #include <wchar.h>
 #endif
 
+struct iovec;
 class UniqueFileDescriptor;
 
 /**
@@ -271,6 +272,18 @@ public:
 	void FullWrite(std::span<const std::byte> src) const;
 
 #ifndef _WIN32
+	/**
+	 * Wrapper for readv().
+	 */
+	[[nodiscard]]
+	ssize_t Read(std::span<const struct iovec> v) const noexcept;
+
+	/**
+	 * Wrapper for writev().
+	 */
+	[[nodiscard]]
+	ssize_t Write(std::span<const struct iovec> v) const noexcept;
+
 	[[nodiscard]]
 	int Poll(short events, int timeout) const noexcept;