pkg/subsystem: restructure the package

Remove the entity and match subpackages.

Regenerate the linux.go file.

1 files changed, 55 insertions, 0 deletions

diff --git a/pkg/subsystem/linux/coincidence.go b/pkg/subsystem/linux/coincidence.go
new file mode 100644
index 000000000..86ee0794f
--- /dev/null
+++ b/pkg/subsystem/linux/coincidence.go
@@ -0,0 +1,55 @@
+// 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 "github.com/google/syzkaller/pkg/subsystem"
+
+// CoincidenceMatrix represents a matrix that, for every pair of subsystems
+// A and B, stores the number of times A and B have coincided in the input data.
+// So far we only need it for subsystem.Subsystem, so its interface is tailored to it.
+type CoincidenceMatrix struct {
+	matrix map[*subsystem.Subsystem]map[*subsystem.Subsystem]int
+}
+
+func MakeCoincidenceMatrix() *CoincidenceMatrix {
+	return &CoincidenceMatrix{
+		matrix: make(map[*subsystem.Subsystem]map[*subsystem.Subsystem]int),
+	}
+}
+
+func (cm *CoincidenceMatrix) Record(items ...*subsystem.Subsystem) {
+	for i := 0; i < len(items); i++ {
+		for j := 0; j < len(items); j++ {
+			cm.inc(items[i], items[j])
+		}
+	}
+}
+
+func (cm *CoincidenceMatrix) Count(a *subsystem.Subsystem) int {
+	return cm.Get(a, a)
+}
+
+func (cm *CoincidenceMatrix) Get(a, b *subsystem.Subsystem) int {
+	return cm.matrix[a][b]
+}
+
+func (cm *CoincidenceMatrix) NonEmptyPairs(cb func(a, b *subsystem.Subsystem, val int)) {
+	for a, sub := range cm.matrix {
+		for b, val := range sub {
+			if a == b {
+				continue
+			}
+			cb(a, b, val)
+		}
+	}
+}
+
+func (cm *CoincidenceMatrix) inc(a, b *subsystem.Subsystem) {
+	subMatrix, ok := cm.matrix[a]
+	if !ok {
+		subMatrix = make(map[*subsystem.Subsystem]int)
+		cm.matrix[a] = subMatrix
+	}
+	subMatrix[b]++
+}