proc/native: support core dumping on FreeBSD (#3305)

Co-authored-by: a <a@kra>

pkg/proc/native/dump_freebsd.go

@@ -0,0 +1,48 @@
+package native
+
+import (
+	"errors"
+	"unsafe"
+
+	"github.com/go-delve/delve/pkg/elfwriter"
+	"github.com/go-delve/delve/pkg/proc"
+)
+
+/*
+#include <sys/types.h>
+#include <sys/user.h>
+#include <libutil.h>
+#include <stdlib.h>
+*/
+import "C"
+
+func (p *nativeProcess) MemoryMap() ([]proc.MemoryMapEntry, error) {
+	var cnt C.int
+	vmentries := C.kinfo_getvmmap(C.int(p.pid), &cnt)
+	if vmentries == nil {
+		return nil, errors.New("kinfo_getvmmap call failed")
+	}
+	defer C.free(unsafe.Pointer(vmentries))
+	r := make([]proc.MemoryMapEntry, 0, int(cnt))
+	base := uintptr(unsafe.Pointer(vmentries))
+	sz := unsafe.Sizeof(C.struct_kinfo_vmentry{})
+	for i := 0; i < int(cnt); i++ {
+		vmentry := (*C.struct_kinfo_vmentry)(unsafe.Pointer(base + sz*uintptr(i)))
+		switch vmentry.kve_type {
+		case C.KVME_TYPE_DEFAULT, C.KVME_TYPE_VNODE, C.KVME_TYPE_SWAP, C.KVME_TYPE_PHYS:
+			r = append(r, proc.MemoryMapEntry{
+				Addr: uint64(vmentry.kve_start),
+				Size: uint64(vmentry.kve_end - vmentry.kve_start),
+
+				Read:  vmentry.kve_protection&C.KVME_PROT_READ != 0,
+				Write: vmentry.kve_protection&C.KVME_PROT_WRITE != 0,
+				Exec:  vmentry.kve_protection&C.KVME_PROT_EXEC != 0,
+			})
+		}
+	}
+	return r, nil
+}
+
+func (p *nativeProcess) DumpProcessNotes(notes []elfwriter.Note, threadDone func()) (threadsDone bool, notesout []elfwriter.Note, err error) {
+	return false, notes, nil
+}

pkg/proc/native/dump_other.go

@@ -1,5 +1,5 @@
-//go:build (freebsd && amd64) || darwin || (windows && arm64)
-// +build freebsd,amd64 darwin windows,arm64
+//go:build darwin || (windows && arm64)
+// +build darwin windows,arm64
 
 package native
 

pkg/proc/native/proc.go

@@ -318,7 +318,7 @@ func (dbp *nativeProcess) initialize(path string, debugInfoDirs []string) (*proc
 		DisableAsyncPreempt: runtime.GOOS == "windows" || (runtime.GOOS == "linux" && runtime.GOARCH == "arm64"),
 
 		StopReason: stopReason,
-		CanDump:    runtime.GOOS == "linux" || (runtime.GOOS == "windows" && runtime.GOARCH == "amd64"),
+		CanDump:    runtime.GOOS == "linux" || runtime.GOOS == "freebsd" || (runtime.GOOS == "windows" && runtime.GOARCH == "amd64"),
 	})
 	procgrp.addTarget = addTarget
 	tgt, err := procgrp.add(dbp, dbp.pid, dbp.memthread, path, stopReason)

pkg/proc/proc_test.go

@@ -5163,7 +5163,7 @@ func TestIssue2319(t *testing.T) {
 }
 
 func TestDump(t *testing.T) {
-	if runtime.GOOS == "freebsd" || (runtime.GOOS == "darwin" && testBackend == "native") || (runtime.GOOS == "windows" && runtime.GOARCH != "amd64") {
+	if (runtime.GOOS == "darwin" && testBackend == "native") || (runtime.GOOS == "windows" && runtime.GOARCH != "amd64") {
 		t.Skip("not supported")
 	}