From 8dfa55df8f41ab538ab59d22977f5726d4111e90 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=B0=A2=E8=87=B4=E9=82=A6=20=28XIE=20Zhibang=29?=
 <Yeking@Red54.com>
Date: Mon, 18 Apr 2022 10:16:33 +0000
Subject: [PATCH] mountinfo: BSDs no longer need cgo nor reflect
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: 谢致邦 (XIE Zhibang) <Yeking@Red54.com>
---
 mountinfo/mounted_unix.go          |  4 +--
 mountinfo/mountinfo_bsd.go         | 44 ++++++++++--------------------
 mountinfo/mountinfo_freebsdlike.go | 14 ++++++++++
 mountinfo/mountinfo_openbsd.go     | 22 +++++++++++++++
 mountinfo/mountinfo_unsupported.go |  4 +--
 5 files changed, 54 insertions(+), 34 deletions(-)
 create mode 100644 mountinfo/mountinfo_freebsdlike.go
 create mode 100644 mountinfo/mountinfo_openbsd.go

diff --git a/mountinfo/mounted_unix.go b/mountinfo/mounted_unix.go
index 242f82cc..c7b7678f 100644
--- a/mountinfo/mounted_unix.go
+++ b/mountinfo/mounted_unix.go
@@ -1,5 +1,5 @@
-//go:build linux || (freebsd && cgo) || (openbsd && cgo) || (darwin && cgo)
-// +build linux freebsd,cgo openbsd,cgo darwin,cgo
+//go:build linux || freebsd || openbsd || darwin
+// +build linux freebsd openbsd darwin
 
 package mountinfo
 
diff --git a/mountinfo/mountinfo_bsd.go b/mountinfo/mountinfo_bsd.go
index d5513a26..8420f58c 100644
--- a/mountinfo/mountinfo_bsd.go
+++ b/mountinfo/mountinfo_bsd.go
@@ -1,53 +1,37 @@
-//go:build (freebsd && cgo) || (openbsd && cgo) || (darwin && cgo)
-// +build freebsd,cgo openbsd,cgo darwin,cgo
+//go:build freebsd || openbsd || darwin
+// +build freebsd openbsd darwin
 
 package mountinfo
 
-/*
-#include <sys/param.h>
-#include <sys/ucred.h>
-#include <sys/mount.h>
-*/
-import "C"
-
-import (
-	"fmt"
-	"reflect"
-	"unsafe"
-)
+import "golang.org/x/sys/unix"
 
 // parseMountTable returns information about mounted filesystems
 func parseMountTable(filter FilterFunc) ([]*Info, error) {
-	var rawEntries *C.struct_statfs
-
-	count := int(C.getmntinfo(&rawEntries, C.MNT_WAIT))
-	if count == 0 {
-		return nil, fmt.Errorf("failed to call getmntinfo")
+	count, err := unix.Getfsstat(nil, unix.MNT_WAIT)
+	if err != nil {
+		return nil, err
 	}
 
-	var entries []C.struct_statfs
-	header := (*reflect.SliceHeader)(unsafe.Pointer(&entries))
-	header.Cap = count
-	header.Len = count
-	header.Data = uintptr(unsafe.Pointer(rawEntries))
+	entries := make([]unix.Statfs_t, count)
+	_, err = unix.Getfsstat(entries, unix.MNT_WAIT)
+	if err != nil {
+		return nil, err
+	}
 
 	var out []*Info
 	for _, entry := range entries {
-		var mountinfo Info
 		var skip, stop bool
-		mountinfo.Mountpoint = C.GoString(&entry.f_mntonname[0])
-		mountinfo.FSType = C.GoString(&entry.f_fstypename[0])
-		mountinfo.Source = C.GoString(&entry.f_mntfromname[0])
+		mountinfo := getMountinfo(&entry)
 
 		if filter != nil {
 			// filter out entries we're not interested in
-			skip, stop = filter(&mountinfo)
+			skip, stop = filter(mountinfo)
 			if skip {
 				continue
 			}
 		}
 
-		out = append(out, &mountinfo)
+		out = append(out, mountinfo)
 		if stop {
 			break
 		}
diff --git a/mountinfo/mountinfo_freebsdlike.go b/mountinfo/mountinfo_freebsdlike.go
new file mode 100644
index 00000000..952787cd
--- /dev/null
+++ b/mountinfo/mountinfo_freebsdlike.go
@@ -0,0 +1,14 @@
+//go:build freebsd || darwin
+// +build freebsd darwin
+
+package mountinfo
+
+import "golang.org/x/sys/unix"
+
+func getMountinfo(entry *unix.Statfs_t) *Info {
+	var mountinfo Info
+	mountinfo.Mountpoint = unix.ByteSliceToString(entry.Mntonname[:])
+	mountinfo.FSType = unix.ByteSliceToString(entry.Fstypename[:])
+	mountinfo.Source = unix.ByteSliceToString(entry.Mntfromname[:])
+	return &mountinfo
+}
diff --git a/mountinfo/mountinfo_openbsd.go b/mountinfo/mountinfo_openbsd.go
new file mode 100644
index 00000000..78ea8cf3
--- /dev/null
+++ b/mountinfo/mountinfo_openbsd.go
@@ -0,0 +1,22 @@
+package mountinfo
+
+import "golang.org/x/sys/unix"
+
+func int8SliceToString(is []int8) string {
+	var bs []byte
+	for _, i := range is {
+		if i == 0 {
+			break
+		}
+		bs = append(bs, byte(i))
+	}
+	return string(bs)
+}
+
+func getMountinfo(entry *unix.Statfs_t) *Info {
+	var mountinfo Info
+	mountinfo.Mountpoint = int8SliceToString(entry.F_mntonname[:])
+	mountinfo.FSType = int8SliceToString(entry.F_fstypename[:])
+	mountinfo.Source = int8SliceToString(entry.F_mntfromname[:])
+	return &mountinfo
+}
diff --git a/mountinfo/mountinfo_unsupported.go b/mountinfo/mountinfo_unsupported.go
index 95769a76..c2e64bc8 100644
--- a/mountinfo/mountinfo_unsupported.go
+++ b/mountinfo/mountinfo_unsupported.go
@@ -1,5 +1,5 @@
-//go:build (!windows && !linux && !freebsd && !openbsd && !darwin) || (freebsd && !cgo) || (openbsd && !cgo) || (darwin && !cgo)
-// +build !windows,!linux,!freebsd,!openbsd,!darwin freebsd,!cgo openbsd,!cgo darwin,!cgo
+//go:build !windows && !linux && !freebsd && !openbsd && !darwin
+// +build !windows,!linux,!freebsd,!openbsd,!darwin
 
 package mountinfo