pkg/subsystem: restructure the package

Remove the entity and match subpackages.

Regenerate the linux.go file.

1 files changed, 49 insertions, 0 deletions

diff --git a/pkg/subsystem/linux/path_coincidence_test.go b/pkg/subsystem/linux/path_coincidence_test.go
new file mode 100644
index 000000000..ac32dcd31
--- /dev/null
+++ b/pkg/subsystem/linux/path_coincidence_test.go
@@ -0,0 +1,49 @@
+// Copyright 2023 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package linux
+
+import (
+	"testing"
+	"testing/fstest"
+
+	"github.com/google/syzkaller/pkg/subsystem"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestBuildCoincidenceMatrix(t *testing.T) {
+	vfs := &subsystem.Subsystem{PathRules: []subsystem.PathRule{
+		{IncludeRegexp: `^fs/`},
+	}}
+	ext4 := &subsystem.Subsystem{PathRules: []subsystem.PathRule{
+		{IncludeRegexp: `^fs/ext4/`},
+	}}
+	ntfs := &subsystem.Subsystem{PathRules: []subsystem.PathRule{
+		{IncludeRegexp: `^fs/ntfs/`},
+	}}
+	kernel := &subsystem.Subsystem{PathRules: []subsystem.PathRule{
+		{IncludeRegexp: `.*`},
+	}}
+
+	fs := fstest.MapFS{
+		".git/obj/12345": {},
+		"fs/inode.c":     {},
+		"fs/ext4/file.c": {},
+		"fs/ntfs/file.c": {},
+		"fs/fat/file.c":  {},
+		"net/socket.c":   {},
+	}
+	matrix, err := BuildCoincidenceMatrix(fs, []*subsystem.Subsystem{vfs, ntfs, ext4, kernel}, nil)
+	assert.NoError(t, err)
+
+	// Test total counts.
+	assert.Equal(t, 5, matrix.Count(kernel))
+	assert.Equal(t, 4, matrix.Count(vfs))
+	assert.Equal(t, 1, matrix.Count(ext4))
+
+	// Test pairwise counts.
+	assert.Equal(t, 1, matrix.Get(vfs, ext4))
+	assert.Equal(t, 1, matrix.Get(vfs, ntfs))
+	assert.Equal(t, 0, matrix.Get(ext4, ntfs))
+	assert.Equal(t, 4, matrix.Get(kernel, vfs))
+}