From fdce6dd4667c670e5a229a64eb6ff4738bea5114 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Tue, 1 Sep 2020 13:49:56 +0100
Subject: [PATCH] cmount: make work under OpenBSD - fixes #1727

---
 cmd/cmount/fs.go                |  9 ++++++++-
 cmd/cmount/mount.go             | 18 ++++++++++--------
 cmd/cmount/mount_test.go        |  2 +-
 cmd/cmount/mount_unsupported.go |  2 +-
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/cmd/cmount/fs.go b/cmd/cmount/fs.go
index 0dcde3289..47d23df41 100644
--- a/cmd/cmount/fs.go
+++ b/cmd/cmount/fs.go
@@ -1,4 +1,4 @@
-//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || windows)
+//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || (openbsd && cgo) || windows)
 
 package cmount
 
@@ -6,6 +6,7 @@ import (
 	"io"
 	"os"
 	"path"
+	"runtime"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -210,6 +211,12 @@ func (fsys *FS) Readdir(dirPath string,
 	// We can't seek in directories and FUSE should know that so
 	// return an error if ofst is ever set.
 	if ofst > 0 {
+		// However openbsd doesn't seem to know this - perhaps a bug in its
+		// FUSE implementation or a bug in cgofuse?
+		// See: https://github.com/billziss-gh/cgofuse/issues/49
+		if runtime.GOOS == "openbsd" {
+			return 0
+		}
 		return -fuse.ESPIPE
 	}
 
diff --git a/cmd/cmount/mount.go b/cmd/cmount/mount.go
index 9bb1ab490..5b23a829e 100644
--- a/cmd/cmount/mount.go
+++ b/cmd/cmount/mount.go
@@ -1,4 +1,4 @@
-//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || windows)
+//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || (openbsd && cgo) || windows)
 
 // Package cmount implements a FUSE mounting system for rclone remotes.
 //
@@ -8,9 +8,9 @@ package cmount
 import (
 	"errors"
 	"fmt"
-	"strings"
 	"os"
 	"runtime"
+	"strings"
 	"time"
 
 	"github.com/rclone/rclone/cmd/mountlib"
@@ -59,12 +59,14 @@ func mountOptions(VFS *vfs.VFS, device string, mountpoint string, opt *mountlib.
 	} else {
 		options = append(options, "-o", "fsname="+device)
 		options = append(options, "-o", "subtype=rclone")
-		options = append(options, "-o", fmt.Sprintf("max_readahead=%d", opt.MaxReadAhead))
-		// This causes FUSE to supply O_TRUNC with the Open
-		// call which is more efficient for cmount.  However
-		// it does not work with cgofuse on Windows with
-		// WinFSP so cmount must work with or without it.
-		options = append(options, "-o", "atomic_o_trunc")
+		if runtime.GOOS != "openbsd" {
+			options = append(options, "-o", fmt.Sprintf("max_readahead=%d", opt.MaxReadAhead))
+			// This causes FUSE to supply O_TRUNC with the Open
+			// call which is more efficient for cmount.  However
+			// it does not work with cgofuse on Windows with
+			// WinFSP so cmount must work with or without it.
+			options = append(options, "-o", "atomic_o_trunc")
+		}
 		if opt.DaemonTimeout != 0 {
 			options = append(options, "-o", fmt.Sprintf("daemon_timeout=%d", int(time.Duration(opt.DaemonTimeout).Seconds())))
 		}
diff --git a/cmd/cmount/mount_test.go b/cmd/cmount/mount_test.go
index e0cc1c4ca..65fb1a97c 100644
--- a/cmd/cmount/mount_test.go
+++ b/cmd/cmount/mount_test.go
@@ -1,4 +1,4 @@
-//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || windows) && (!race || !windows)
+//go:build cmount && ((linux && cgo) || (darwin && cgo) || (freebsd && cgo) || (openbsd && cgo) || windows) && (!race || !windows)
 
 // Package cmount implements a FUSE mounting system for rclone remotes.
 //
diff --git a/cmd/cmount/mount_unsupported.go b/cmd/cmount/mount_unsupported.go
index 6677132d7..816900f3f 100644
--- a/cmd/cmount/mount_unsupported.go
+++ b/cmd/cmount/mount_unsupported.go
@@ -1,4 +1,4 @@
-//go:build !((linux && cgo && cmount) || (darwin && cgo && cmount) || (freebsd && cgo && cmount) || (windows && cmount))
+//go:build !((linux && cgo && cmount) || (darwin && cgo && cmount) || (freebsd && cgo && cmount) || (openbsd && cgo && cmount) || (windows && cmount))
 
 // Package cmount implements a FUSE mounting system for rclone remotes.
 //