whatcanGOwrong

go/pkg/mod/github.com/cilium/ebpf@v0.11.0/btf/handle_test.go

@@ -0,0 +1,99 @@
+package btf_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/cilium/ebpf/btf"
+	"github.com/cilium/ebpf/internal/testutils"
+)
+
+func TestHandleIterator(t *testing.T) {
+	// There is no guarantee that there is a BTF ID allocated, but loading a module
+	// triggers loading vmlinux.
+	// See https://github.com/torvalds/linux/commit/5329722057d41aebc31e391907a501feaa42f7d9
+	testutils.SkipOnOldKernel(t, "5.11", "vmlinux BTF ID")
+
+	it := new(btf.HandleIterator)
+	defer it.Handle.Close()
+
+	if !it.Next() {
+		t.Fatalf("No BTF loaded")
+	}
+	if it.Handle == nil {
+		t.Fatal("Next doesn't assign handle")
+	}
+	prev := it.ID
+	for it.Next() {
+		// Iterate all loaded BTF.
+		if it.Handle == nil {
+			t.Fatal("Next doesn't assign handle")
+		}
+		if it.ID == prev {
+			t.Fatal("Iterator doesn't advance ID")
+		}
+		prev = it.ID
+	}
+	if err := it.Err(); err != nil {
+		t.Fatal("Iteration returned an error:", err)
+	}
+
+	if it.Handle != nil {
+		t.Fatal("Next doesn't clean up handle on last iteration")
+	}
+	if prev != it.ID {
+		t.Fatal("Next changes ID on last iteration")
+	}
+}
+
+func TestParseModuleSplitSpec(t *testing.T) {
+	// See TestNewHandleFromID for reasoning.
+	testutils.SkipOnOldKernel(t, "5.11", "vmlinux BTF ID")
+
+	module, err := btf.FindHandle(func(info *btf.HandleInfo) bool {
+		if info.IsModule() {
+			t.Log("Using module", info.Name)
+			return true
+		}
+		return false
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer module.Close()
+
+	vmlinux, err := btf.FindHandle(func(info *btf.HandleInfo) bool {
+		return info.IsVmlinux()
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer vmlinux.Close()
+
+	base, err := vmlinux.Spec(nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = module.Spec(base)
+	if err != nil {
+		t.Fatal("Parse module BTF:", err)
+	}
+}
+
+func ExampleHandleIterator() {
+	it := new(btf.HandleIterator)
+	defer it.Handle.Close()
+
+	for it.Next() {
+		info, err := it.Handle.Info()
+		if err != nil {
+			panic(err)
+		}
+
+		fmt.Printf("Found handle with ID %d and name %s\n", it.ID, info.Name)
+	}
+	if err := it.Err(); err != nil {
+		panic(err)
+	}
+}