Mock syscall.

db.go

@@ -27,6 +27,7 @@ type DB struct {
 	opened bool
 
 	os       _os
+	syscall  _syscall
 	file     file
 	metafile file
 	data     []byte
@@ -71,6 +72,9 @@ func (db *DB) Open(path string, mode os.FileMode) error {
 	if db.os == nil {
 		db.os = &sysos{}
 	}
+	if db.syscall == nil {
+		db.syscall = &syssyscall{}
+	}
 
 	// Exit if the database is currently open.
 	if db.opened {
@@ -145,7 +149,7 @@ func (db *DB) mmap() error {
 
 	// Determine the map size based on the file size.
 	var size int
-	if info, err := db.os.Stat(db.file.Name()); err != nil {
+	if info, err := db.os.Stat(db.path); err != nil {
 		return err
 	} else if info.Size() < int64(db.pageSize*2) {
 		return &Error{"file size too small", nil}
@@ -154,7 +158,7 @@ func (db *DB) mmap() error {
 	}
 
 	// Memory-map the data file as a byte slice.
-	if db.data, err = syscall.Mmap(int(db.file.Fd()), 0, size, syscall.PROT_READ, syscall.MAP_SHARED); err != nil {
+	if db.data, err = db.syscall.Mmap(int(db.file.Fd()), 0, size, syscall.PROT_READ, syscall.MAP_SHARED); err != nil {
 		return err
 	}
 

db_test.go

@@ -47,6 +47,20 @@ func TestDBOpenMetaFileError(t *testing.T) {
 	})
 }
 
+// Ensure that the database limits the upper bound of the page size.
+/*
+func TestDBLimitPageSize(t *testing.T) {
+	withMockDB(func(db *DB, mockos *mockos, path string) {
+		buf := make([]byte, 4096)
+		mockos.On("OpenFile", path, os.O_RDWR|os.O_CREATE, os.FileMode(0666)).Return(&mockfile{}, nil)
+		mockos.On("OpenFile", path, os.O_RDWR|os.O_SYNC, os.FileMode(0666)).Return(&mockfile{}, nil)
+		mockos.On("OpenFile", path, os.O_RDWR|os.O_SYNC, os.FileMode(0666)).Return(&mockfile{}, nil)
+		err := db.Open(path, 0666)
+		assert.Equal(t, err, exp)
+	})
+}
+*/
+
 // withDB executes a function with a database reference.
 func withDB(fn func(*DB, string)) {
 	f, _ := ioutil.TempFile("", "bolt-")

file.go

@@ -2,7 +2,6 @@ package bolt
 
 type file interface {
 	Fd() uintptr
-	Name() string
 	ReadAt(b []byte, off int64) (n int, err error)
 	WriteAt(b []byte, off int64) (n int, err error)
 }

file_test.go

@@ -6,18 +6,13 @@ import (
 
 type mockfile struct {
 	mock.Mock
-	fd   uintptr
-	name string
+	fd uintptr
 }
 
 func (m *mockfile) Fd() uintptr {
 	return m.fd
 }
 
-func (m *mockfile) Name() string {
-	return m.name
-}
-
 func (m *mockfile) ReadAt(b []byte, off int64) (n int, err error) {
 	args := m.Called(b, off)
 	return args.Int(0), args.Error(1)

syscall_darwin.go

@@ -0,0 +1,16 @@
+package bolt
+
+import (
+	"syscall"
+)
+
+type _syscall interface {
+	Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error)
+}
+
+type syssyscall struct{}
+
+func (o *syssyscall) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
+	// err = (EACCES, EBADF, EINVAL, ENODEV, ENOMEM, ENXIO, EOVERFLOW)
+	return syscall.Mmap(fd, offset, length, prot, flags)
+}

syscall_darwin_test.go

@@ -0,0 +1,14 @@
+package bolt
+
+import (
+	"github.com/stretchr/testify/mock"
+)
+
+type mocksyscall struct {
+	mock.Mock
+}
+
+func (m *mocksyscall) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
+	args := m.Called(fd, offset, length, prot, flags)
+	return args.Get(0).([]byte), args.Error(1)
+}