cmd/sharefs: expand fuse_main

This change should not change behaviour other than making output more consistent.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/sharefs/fuse.go

@@ -25,6 +25,8 @@ import (
 	"strconv"
 	"syscall"
 	"unsafe"
+
+	"hakurei.app/internal/info"
 )
 
 type (
@@ -207,6 +209,8 @@ func unsafeAddArgument(args *fuseArgs, arg string) {
 }
 
 func _main(argc int, argv **C.char) int {
+	runtime.LockOSThread()
+
 	// don't mask creation mode, kernel already did that
 	syscall.Umask(0)
 
@@ -222,6 +226,34 @@ func _main(argc int, argv **C.char) int {
 	var priv C.struct_sharefs_private
 	pinner.Pin(&priv)
 
+	var opts C.struct_fuse_cmdline_opts
+	if C.fuse_parse_cmdline(&args, &opts) != 0 {
+		return 1
+	}
+	defer func() {
+		if opts.mountpoint != nil {
+			C.free(unsafe.Pointer(opts.mountpoint))
+		}
+		C.fuse_opt_free_args(&args)
+	}()
+
+	if opts.show_version != 0 {
+		fmt.Println("hakurei version", info.Version())
+		fmt.Println("FUSE library version", C.GoString(C.fuse_pkgversion()))
+		C.fuse_lowlevel_version()
+		return 0
+	}
+
+	if opts.show_help != 0 {
+		showHelp(&args)
+		return 0
+	}
+
+	if opts.show_help == 0 && opts.mountpoint == nil {
+		log.Println("no mountpoint specified")
+		return 2
+	}
+
 	{
 		source, setuid, setgid, ret := parseOpts(&args)
 		if ret != 0 {
@@ -247,8 +279,7 @@ func _main(argc int, argv **C.char) int {
 		priv.setuid, priv.setgid = C.uintptr_t(setuid), C.uintptr_t(setgid)
 	}
 
-	// TODO(ophestra): spawn container here, set PR_SET_NO_NEW_PRIVS and enforce landlock
-	fuse_main_return := C._fuse_main(args.argc, args.argv, &C.struct_fuse_operations{
+	op := C.struct_fuse_operations{
 		init:    closure(C.sharefs_init),
 		destroy: closure(C.sharefs_destroy),
 
@@ -268,11 +299,52 @@ func _main(argc int, argv **C.char) int {
 		statfs:   closure(C.sharefs_statfs),
 		release:  closure(C.sharefs_release),
 		fsync:    closure(C.sharefs_fsync),
-	}, unsafe.Pointer(&priv))
+	}
+
+	fuse := C.fuse_new_fn(&args, &op, C.size_t(unsafe.Sizeof(op)), unsafe.Pointer(&priv))
+	if fuse == nil {
+		return 3
+	}
+	defer C.fuse_destroy(fuse)
+
+	if C.fuse_mount(fuse, opts.mountpoint) != 0 {
+		return 4
+	}
+	defer C.fuse_unmount(fuse)
+
+	// TODO(ophestra): spawn container here, set PR_SET_NO_NEW_PRIVS and enforce landlock
+	if C.fuse_daemonize(opts.foreground) != 0 {
+		return 5
+	}
+
+	se := C.fuse_get_session(fuse)
+	if C.fuse_set_signal_handlers(se) != 0 {
+		return 6
+	}
+	defer C.fuse_remove_signal_handlers(se)
+
+	if opts.singlethread != 0 {
+		if C.fuse_loop(fuse) != 0 {
+			return 8
+		}
+	} else {
+		loopConfig := C.fuse_loop_cfg_create()
+		if loopConfig == nil {
+			return 7
+		}
+		defer C.fuse_loop_cfg_destroy(loopConfig)
+
+		C.fuse_loop_cfg_set_clone_fd(loopConfig, C.uint(opts.clone_fd))
+
+		C.fuse_loop_cfg_set_idle_threads(loopConfig, opts.max_idle_threads)
+		C.fuse_loop_cfg_set_max_threads(loopConfig, opts.max_threads)
+		if C.fuse_loop_mt(fuse, loopConfig) != 0 {
+			return 8
+		}
+	}
 
 	if priv.init_failed {
 		return 1
-	} else {
-		return int(fuse_main_return)
 	}
+	return 0
 }