From e1d7ce4640c4c897c19398c4c1d7522db35db34d Mon Sep 17 00:00:00 2001
From: Haruue <i@haruue.moe>
Date: Fri, 5 Apr 2024 10:49:03 +0800
Subject: [PATCH] chore: a better fix for 32-bit unix.Timeval

Why there is no decltype() in Golang?

At least we got generics now.

ref: 9520d840942d3950ed43af281935c262fac35615
---
 app/internal/sockopts/sockopts_linux.go   | 12 +++++++++++-
 app/internal/sockopts/timeval_linux_32.go | 15 ---------------
 app/internal/sockopts/timeval_linux_64.go | 15 ---------------
 3 files changed, 11 insertions(+), 31 deletions(-)
 delete mode 100644 app/internal/sockopts/timeval_linux_32.go
 delete mode 100644 app/internal/sockopts/timeval_linux_64.go

diff --git a/app/internal/sockopts/sockopts_linux.go b/app/internal/sockopts/sockopts_linux.go
index e51e75a..ce188d9 100644
--- a/app/internal/sockopts/sockopts_linux.go
+++ b/app/internal/sockopts/sockopts_linux.go
@@ -7,6 +7,8 @@ import (
 	"net"
 	"time"
 
+	"golang.org/x/exp/constraints"
+
 	"golang.org/x/sys/unix"
 )
 
@@ -58,7 +60,11 @@ func fdControlUnixSocketImpl(c *net.UDPConn, path string) error {
 		}
 		defer unix.Close(socketFd)
 
-		timeout := unixTimeval()
+		var timeout unix.Timeval
+		timeUsec := fdControlUnixTimeout.Microseconds()
+		castAssignInteger(timeUsec/1e6, &timeout.Sec)
+		// Specifying the type explicitly is not necessary here, but it makes GoLand happy.
+		castAssignInteger[int64](timeUsec%1e6, &timeout.Usec)
 
 		_ = unix.SetsockoptTimeval(socketFd, unix.SOL_SOCKET, unix.SO_RCVTIMEO, &timeout)
 		_ = unix.SetsockoptTimeval(socketFd, unix.SOL_SOCKET, unix.SO_SNDTIMEO, &timeout)
@@ -85,3 +91,7 @@ func fdControlUnixSocketImpl(c *net.UDPConn, path string) error {
 		return nil
 	})
 }
+
+func castAssignInteger[F, T constraints.Integer](from F, to *T) {
+	*to = T(from)
+}
diff --git a/app/internal/sockopts/timeval_linux_32.go b/app/internal/sockopts/timeval_linux_32.go
deleted file mode 100644
index af8c262..0000000
--- a/app/internal/sockopts/timeval_linux_32.go
+++ /dev/null
@@ -1,15 +0,0 @@
-//go:build linux && (386 || arm || mips || mipsle || ppc)
-
-package sockopts
-
-import (
-	"golang.org/x/sys/unix"
-)
-
-func unixTimeval() unix.Timeval {
-	timeUsec := fdControlUnixTimeout.Microseconds()
-	return unix.Timeval{
-		Sec:  int32(timeUsec / 1e6),
-		Usec: int32(timeUsec % 1e6),
-	}
-}
diff --git a/app/internal/sockopts/timeval_linux_64.go b/app/internal/sockopts/timeval_linux_64.go
deleted file mode 100644
index 407438c..0000000
--- a/app/internal/sockopts/timeval_linux_64.go
+++ /dev/null
@@ -1,15 +0,0 @@
-//go:build linux && (amd64 || arm64 || loong64 || mips64 || mips64le || ppc64 || ppc64le || riscv64 || s390x || sparc64)
-
-package sockopts
-
-import (
-	"golang.org/x/sys/unix"
-)
-
-func unixTimeval() unix.Timeval {
-	timeUsec := fdControlUnixTimeout.Microseconds()
-	return unix.Timeval{
-		Sec:  timeUsec / 1e6,
-		Usec: timeUsec % 1e6,
-	}
-}