p7 add attach-time trace dimension gating

4 files changed, 183 insertions, 5 deletions

diff --git a/internal/generate/bpfhandler.go b/internal/generate/bpfhandler.go
index 9365c52..dce776a 100644
--- a/internal/generate/bpfhandler.go
+++ b/internal/generate/bpfhandler.go
@@ -23,9 +23,9 @@ func generateBPFHandler(tp GeneratedTracepoint) string {
 	}
 
 	eventStruct := eventStructName(tp.Classification.Kind)
-	comment := eventStruct
+	comment := fmt.Sprintf("%s (kind=%s)", eventStruct, tp.Classification.Kind.MetadataName())
 	if tp.Classification.Kind == KindRet {
-		comment = fmt.Sprintf("%s (%s)", eventStruct, ClassifyRet(f.Name))
+		comment = fmt.Sprintf("%s (%s) (kind=%s)", eventStruct, ClassifyRet(f.Name), tp.Classification.Kind.MetadataName())
 	}
 
 	eventTypeConst := eventTypeConstant(tp.Classification.Kind, isEnter)
diff --git a/internal/generate/classify.go b/internal/generate/classify.go
index af7d78d..9e9df9c 100644
--- a/internal/generate/classify.go
+++ b/internal/generate/classify.go
@@ -32,6 +32,61 @@ const (
 	KindPerfOpen
 )
 
+func (k TracepointKind) MetadataName() string {
+	switch k {
+	case KindFd:
+		return "fd"
+	case KindOpen:
+		return "open"
+	case KindMqOpen:
+		return "mq-open"
+	case KindExec:
+		return "exec"
+	case KindPathname:
+		return "pathname"
+	case KindName:
+		return "name"
+	case KindRet:
+		return "ret"
+	case KindFcntl:
+		return "fcntl"
+	case KindNull:
+		return "null"
+	case KindDup3:
+		return "dup3"
+	case KindOpenByHandleAt:
+		return "open-by-handle-at"
+	case KindSocket:
+		return "socket"
+	case KindSocketpair:
+		return "socketpair"
+	case KindAccept:
+		return "accept"
+	case KindPipe:
+		return "pipe"
+	case KindEventfd:
+		return "eventfd"
+	case KindEpollCtl:
+		return "epoll-ctl"
+	case KindTwoFd:
+		return "two-fd"
+	case KindPoll:
+		return "poll"
+	case KindMem:
+		return "mem"
+	case KindSleep:
+		return "sleep"
+	case KindKeyctl:
+		return "keyctl"
+	case KindPtrace:
+		return "ptrace"
+	case KindPerfOpen:
+		return "perf-open"
+	default:
+		return "none"
+	}
+}
+
 type RetClassification string
 
 const (
diff --git a/internal/generate/tracepointsgo.go b/internal/generate/tracepointsgo.go
index 0542f64..9d92047 100644
--- a/internal/generate/tracepointsgo.go
+++ b/internal/generate/tracepointsgo.go
@@ -5,14 +5,35 @@ import (
 	"fmt"
 	"io"
 	"regexp"
+	"sort"
 	"strings"
 )
 
 var secRe = regexp.MustCompile(`^SEC.*sys_((?:enter|exit)_[a-z_0-9]+)`)
+var kindLineRe = regexp.MustCompile(`^(sys_enter_[a-z0-9_]+)\s+is a struct\s+([a-z0-9_]+)\s*$`)
 
 // ExtractTracepoints reads generated C code and extracts tracepoint names from
 // SEC annotations, producing the generated_tracepoints.go content.
 func ExtractTracepoints(r io.Reader) (string, error) {
+	return ExtractTracepointsWithKinds(r, strings.NewReader(""))
+}
+
+// ExtractTracepointsWithKinds reads generated C code and the
+// generated_tracepoints_result.txt metadata to produce
+// internal/tracepoints/generated_tracepoints.go.
+func ExtractTracepointsWithKinds(cReader io.Reader, kindsReader io.Reader) (string, error) {
+	tracepoints, err := extractTracepoints(cReader)
+	if err != nil {
+		return "", err
+	}
+	syscallKinds, err := extractSyscallKinds(kindsReader)
+	if err != nil {
+		return "", err
+	}
+	return formatTracepointsGo(tracepoints, syscallKinds), nil
+}
+
+func extractTracepoints(r io.Reader) ([]string, error) {
 	scanner := bufio.NewScanner(r)
 	var tracepoints []string
 
@@ -24,13 +45,58 @@ func ExtractTracepoints(r io.Reader) (string, error) {
 	}
 
 	if err := scanner.Err(); err != nil {
-		return "", fmt.Errorf("scanning input: %w", err)
+		return nil, fmt.Errorf("scanning input: %w", err)
 	}
+	return tracepoints, nil
+}
 
-	return formatTracepointsGo(tracepoints), nil
+func extractSyscallKinds(r io.Reader) (map[string]string, error) {
+	kinds := make(map[string]string)
+	if r == nil {
+		return kinds, nil
+	}
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if line == "" {
+			continue
+		}
+		m := kindLineRe.FindStringSubmatch(line)
+		if m == nil {
+			continue
+		}
+		syscall := strings.TrimPrefix(m[1], "sys_enter_")
+		kind := normalizeStructKind(m[2])
+		if kind == "" {
+			continue
+		}
+		kinds[syscall] = kind
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("scan kind metadata: %w", err)
+	}
+	return kinds, nil
+}
+
+func normalizeStructKind(structName string) string {
+	base := strings.TrimSuffix(structName, "_event")
+	switch base {
+	case "mq_open":
+		return "mq-open"
+	case "open_by_handle_at":
+		return "open-by-handle-at"
+	case "two_fd":
+		return "two-fd"
+	case "epoll_ctl":
+		return "epoll-ctl"
+	case "perf_open":
+		return "perf-open"
+	default:
+		return base
+	}
 }
 
-func formatTracepointsGo(tracepoints []string) string {
+func formatTracepointsGo(tracepoints []string, syscallKinds map[string]string) string {
 	var b strings.Builder
 	b.WriteString("// Code generated - don't change manually!\n")
 	b.WriteString("package tracepoints\n\n")
@@ -39,5 +105,40 @@ func formatTracepointsGo(tracepoints []string) string {
 		fmt.Fprintf(&b, "\t%q,\n", tp)
 	}
 	b.WriteString("}\n")
+	b.WriteString("\n")
+	b.WriteString("var syscallFamilies = map[string]string{\n")
+	syscallFamilies := make(map[string]string)
+	for _, tp := range tracepoints {
+		syscall := strings.TrimPrefix(tp, "sys_enter_")
+		syscall = strings.TrimPrefix(syscall, "sys_exit_")
+		if syscall == "" {
+			continue
+		}
+		if _, ok := syscallFamilies[syscall]; ok {
+			continue
+		}
+		family := ClassifySyscallFamily("sys_enter_" + syscall)
+		syscallFamilies[syscall] = string(family)
+	}
+	familySyscalls := make([]string, 0, len(syscallFamilies))
+	for syscall := range syscallFamilies {
+		familySyscalls = append(familySyscalls, syscall)
+	}
+	sort.Strings(familySyscalls)
+	for _, syscall := range familySyscalls {
+		fmt.Fprintf(&b, "\t%q: %q,\n", syscall, syscallFamilies[syscall])
+	}
+	b.WriteString("}\n")
+	b.WriteString("\n")
+	b.WriteString("var syscallKinds = map[string]string{\n")
+	syscalls := make([]string, 0, len(syscallKinds))
+	for syscall := range syscallKinds {
+		syscalls = append(syscalls, syscall)
+	}
+	sort.Strings(syscalls)
+	for _, syscall := range syscalls {
+		fmt.Fprintf(&b, "\t%q: %q,\n", syscall, syscallKinds[syscall])
+	}
+	b.WriteString("}\n")
 	return b.String()
 }
diff --git a/internal/generate/tracepointsgo_test.go b/internal/generate/tracepointsgo_test.go
index 978633b..ebad63d 100644
--- a/internal/generate/tracepointsgo_test.go
+++ b/internal/generate/tracepointsgo_test.go
@@ -51,6 +51,8 @@ func TestExtractTracepoints(t *testing.T) {
 	requireContains(t, output, `"sys_enter_close",`)
 	requireContains(t, output, `"sys_exit_close",`)
 	requireContains(t, output, "var List = []string{")
+	requireContains(t, output, "var syscallFamilies = map[string]string{")
+	requireContains(t, output, "var syscallKinds = map[string]string{")
 
 	// Should NOT contain ignore comments or defines
 	if strings.Contains(output, "kill") {
@@ -78,6 +80,8 @@ func TestExtractTracepointsEmpty(t *testing.T) {
 		t.Fatal(err)
 	}
 	requireContains(t, output, "var List = []string{")
+	requireContains(t, output, "var syscallFamilies = map[string]string{")
+	requireContains(t, output, "var syscallKinds = map[string]string{")
 	requireContains(t, output, "}")
 }
 
@@ -115,7 +119,25 @@ func TestExtractTracepointsNoSECLines(t *testing.T) {
 		t.Fatalf("unexpected error: %v", err)
 	}
 	requireContains(t, output, "var List = []string{")
+	requireContains(t, output, "var syscallFamilies = map[string]string{")
+	requireContains(t, output, "var syscallKinds = map[string]string{")
 	if strings.Contains(output, `"sys_`) {
 		t.Error("input with no SEC lines should produce empty list")
 	}
 }
+
+func TestExtractTracepointsWithKinds(t *testing.T) {
+	kindData := `sys_enter_read is a struct fd_event
+sys_enter_open_by_handle_at is a struct open_by_handle_at_event
+sys_enter_mq_open is a struct mq_open_event
+sys_enter_epoll_ctl is a struct epoll_ctl_event
+`
+	output, err := ExtractTracepointsWithKinds(strings.NewReader(sampleGeneratedC), strings.NewReader(kindData))
+	if err != nil {
+		t.Fatalf("ExtractTracepointsWithKinds failed: %v", err)
+	}
+	requireContains(t, output, `"read": "fd",`)
+	requireContains(t, output, `"open_by_handle_at": "open-by-handle-at",`)
+	requireContains(t, output, `"mq_open": "mq-open",`)
+	requireContains(t, output, `"epoll_ctl": "epoll-ctl",`)
+}