From d2bc081420173afc65c0f22041fdd23892874678 Mon Sep 17 00:00:00 2001
From: Tobias Klauser <tklauser@distanz.ch>
Date: Mon, 16 Oct 2017 10:36:49 +0200
Subject: [PATCH] libcontainer: merge common syscall implementations

There are essentially two possible implementations for Setuid/Setgid on
Linux, either using SYS_SETUID32/SYS_SETGID32 or SYS_SETUID/SYS_SETGID,
depending on the architecture (see golang/go#1435 for why Setuid/Setgid
aren currently implemented for Linux neither in syscall nor in
golang.org/x/sys/unix).

Reduce duplication by merging the currently implemented variants and
adjusting the build tags accordingly.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
---
 ...scall_linux_386.go => syscall_linux_32.go} |  3 ++-
 libcontainer/system/syscall_linux_64.go       |  3 ++-
 libcontainer/system/syscall_linux_arm.go      | 25 -------------------
 libcontainer/system/syscall_linux_mipsx.go    | 25 -------------------
 4 files changed, 4 insertions(+), 52 deletions(-)
 rename libcontainer/system/{syscall_linux_386.go => syscall_linux_32.go} (93%)
 delete mode 100644 libcontainer/system/syscall_linux_arm.go
 delete mode 100644 libcontainer/system/syscall_linux_mipsx.go

diff --git a/libcontainer/system/syscall_linux_386.go b/libcontainer/system/syscall_linux_32.go
similarity index 93%
rename from libcontainer/system/syscall_linux_386.go
rename to libcontainer/system/syscall_linux_32.go
index 3f7235ed1..c5ca5d862 100644
--- a/libcontainer/system/syscall_linux_386.go
+++ b/libcontainer/system/syscall_linux_32.go
@@ -1,4 +1,5 @@
-// +build linux,386
+// +build linux
+// +build 386 arm
 
 package system
 
diff --git a/libcontainer/system/syscall_linux_64.go b/libcontainer/system/syscall_linux_64.go
index d7891a2ff..11c3faafb 100644
--- a/libcontainer/system/syscall_linux_64.go
+++ b/libcontainer/system/syscall_linux_64.go
@@ -1,4 +1,5 @@
-// +build linux,arm64 linux,amd64 linux,ppc linux,ppc64 linux,ppc64le linux,s390x
+// +build linux
+// +build arm64 amd64 mips mipsle mips64 mips64le ppc ppc64 ppc64le s390x
 
 package system
 
diff --git a/libcontainer/system/syscall_linux_arm.go b/libcontainer/system/syscall_linux_arm.go
deleted file mode 100644
index 31ff3deb1..000000000
--- a/libcontainer/system/syscall_linux_arm.go
+++ /dev/null
@@ -1,25 +0,0 @@
-// +build linux,arm
-
-package system
-
-import (
-	"golang.org/x/sys/unix"
-)
-
-// Setuid sets the uid of the calling thread to the specified uid.
-func Setuid(uid int) (err error) {
-	_, _, e1 := unix.RawSyscall(unix.SYS_SETUID32, uintptr(uid), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// Setgid sets the gid of the calling thread to the specified gid.
-func Setgid(gid int) (err error) {
-	_, _, e1 := unix.RawSyscall(unix.SYS_SETGID32, uintptr(gid), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
diff --git a/libcontainer/system/syscall_linux_mipsx.go b/libcontainer/system/syscall_linux_mipsx.go
deleted file mode 100644
index 98a3f088b..000000000
--- a/libcontainer/system/syscall_linux_mipsx.go
+++ /dev/null
@@ -1,25 +0,0 @@
-// +build linux,mips linux,mipsle linux,mips64 linux,mips64le
-
-package system
-
-import (
-	"syscall"
-)
-
-// Setuid sets the uid of the calling thread to the specified uid.
-func Setuid(uid int) (err error) {
-	_, _, e1 := syscall.RawSyscall(syscall.SYS_SETUID, uintptr(uid), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// Setgid sets the gid of the calling thread to the specified gid.
-func Setgid(gid int) (err error) {
-	_, _, e1 := syscall.RawSyscall(syscall.SYS_SETGID, uintptr(gid), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}