[op] Replace syscall package usage with golang.org/x/sys/unix in pkg/.

The syscall package has been deprecated in favor of golang.org/x/sys.

Note that syscall is still used in the following places:
- pkg/sentry/socket/hostinet/stack.go: some netlink related functionalities
  are not yet available in golang.org/x/sys.
- syscall.Stat_t is still used in some places because os.FileInfo.Sys() still
  returns it and not unix.Stat_t.

Updates #214

PiperOrigin-RevId: 360701387

3 files changed, 15 insertions, 14 deletions

diff --git a/pkg/iovec/BUILD b/pkg/iovec/BUILD
index eda82cfc1..b92a58556 100644
--- a/pkg/iovec/BUILD
+++ b/pkg/iovec/BUILD
@@ -6,7 +6,10 @@ go_library(
     name = "iovec",
     srcs = ["iovec.go"],
     visibility = ["//:sandbox"],
-    deps = ["//pkg/abi/linux"],
+    deps = [
+        "//pkg/abi/linux",
+        "@org_golang_x_sys//unix:go_default_library",
+    ],
 )
 
 go_test(
diff --git a/pkg/iovec/iovec.go b/pkg/iovec/iovec.go
index dd70fe80f..0789c74bf 100644
--- a/pkg/iovec/iovec.go
+++ b/pkg/iovec/iovec.go
@@ -19,18 +19,17 @@
 package iovec
 
 import (
-	"syscall"
-
+	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/abi/linux"
 )
 
 // MaxIovs is the maximum number of iovecs host platform can accept.
 var MaxIovs = linux.UIO_MAXIOV
 
-// Builder is a builder for slice of syscall.Iovec.
+// Builder is a builder for slice of unix.Iovec.
 type Builder struct {
-	iovec   []syscall.Iovec
-	storage [8]syscall.Iovec
+	iovec   []unix.Iovec
+	storage [8]unix.Iovec
 
 	// overflow tracks the last buffer when iovec length is at MaxIovs.
 	overflow []byte
@@ -48,7 +47,7 @@ func (b *Builder) Add(buf []byte) {
 		b.addByAppend(buf)
 		return
 	}
-	b.iovec = append(b.iovec, syscall.Iovec{
+	b.iovec = append(b.iovec, unix.Iovec{
 		Base: &buf[0],
 		Len:  uint64(len(buf)),
 	})
@@ -62,7 +61,7 @@ func (b *Builder) Add(buf []byte) {
 
 func (b *Builder) addByAppend(buf []byte) {
 	b.overflow = append(b.overflow, buf...)
-	b.iovec[len(b.iovec)-1] = syscall.Iovec{
+	b.iovec[len(b.iovec)-1] = unix.Iovec{
 		Base: &b.overflow[0],
 		Len:  uint64(len(b.overflow)),
 	}
@@ -70,6 +69,6 @@ func (b *Builder) addByAppend(buf []byte) {
 
 // Build returns the final Iovec slice. The length of returned iovec will not
 // excceed MaxIovs.
-func (b *Builder) Build() []syscall.Iovec {
+func (b *Builder) Build() []unix.Iovec {
 	return b.iovec
 }
diff --git a/pkg/iovec/iovec_test.go b/pkg/iovec/iovec_test.go
index a3900c299..f6deb4208 100644
--- a/pkg/iovec/iovec_test.go
+++ b/pkg/iovec/iovec_test.go
@@ -19,7 +19,6 @@ package iovec
 import (
 	"bytes"
 	"fmt"
-	"syscall"
 	"testing"
 	"unsafe"
 
@@ -100,16 +99,16 @@ func TestBuilderBuildMaxIov(t *testing.T) {
 			if err := unix.Pipe(fds[:]); err != nil {
 				t.Fatalf("Pipe: %v", err)
 			}
-			defer syscall.Close(fds[0])
-			defer syscall.Close(fds[1])
+			defer unix.Close(fds[0])
+			defer unix.Close(fds[1])
 
-			wrote, _, e := syscall.RawSyscall(syscall.SYS_WRITEV, uintptr(fds[1]), uintptr(unsafe.Pointer(&iovec[0])), uintptr(len(iovec)))
+			wrote, _, e := unix.RawSyscall(unix.SYS_WRITEV, uintptr(fds[1]), uintptr(unsafe.Pointer(&iovec[0])), uintptr(len(iovec)))
 			if int(wrote) != len(data) || e != 0 {
 				t.Fatalf("writev: %v, %v; want %v, 0", wrote, e, len(data))
 			}
 
 			got := make([]byte, len(data))
-			if n, err := syscall.Read(fds[0], got); n != len(got) || err != nil {
+			if n, err := unix.Read(fds[0], got); n != len(got) || err != nil {
 				t.Fatalf("read: %v, %v; want %v, nil", n, err, len(got))
 			}