New BiF record_field_vals() that returns the fields of a record in a

table with meta-information.

Example:

type r: record {
	a: count;
	b: string &default="Foo";
	c: double &optional;
	d: string &log;
};

event bro_init()
{
    local x: r = [$a=42, $d="Bar"];
    print record_fields(x);
}

This prints:

  {
  [a] = [type_name=record, log=F, value=42, default_val=<uninitialized>]
  [b] = [type_name=record, log=F, value=<uninitialized>, default_val=Foo],
  [c] = [type_name=record, log=F, value=<uninitialized>, default_val=<uninitialized>],
  [d] = [type_name=record, log=T, value=Bar, default_val=<uninitialized>],
  }

This is one more step in Seth's quest for full inspection support. :-)

policy/bro.init

@@ -183,6 +183,17 @@ type script_id: record {
 	value: any &optional;
 };
 
+type id_table: table[string] of script_id;
+
+type record_field: record {
+	type_name: string;
+	log: bool;
+	value: any &optional;
+	default_val: any &optional;
+};
+
+type record_field_table: table[string] of record_field;
+
 # The following two variables are defined here until the core is not
 # dependent on the names remaining as they are now.
 ## This is the list of capture filters indexed by some user-definable ID.
@@ -190,8 +201,6 @@ global capture_filters: table[string] of string &redef;
 ## This is the list of restriction filters indexed by some user-definable ID.
 global restrict_filters: table[string] of string &redef;
 
-type id_table: table[string] of script_id;
-
 # {precompile,install}_pcap_filter identify the filter by IDs
 type PcapFilterID: enum { None };
 

src/NetVar.cc

@@ -248,6 +248,8 @@ int record_all_packets;
 
 RecordType* script_id;
 TableType* id_table;
+RecordType* record_field;
+TableType* record_field_table;
 
 StringVal* cmd_line_bpf_filter;
 
@@ -550,4 +552,6 @@ void init_net_var()
 
 	script_id = internal_type("script_id")->AsRecordType();
 	id_table = internal_type("id_table")->AsTableType();
+	record_field = internal_type("record_field")->AsRecordType();
+	record_field_table = internal_type("record_field_table")->AsTableType();
 	}

src/NetVar.h

@@ -251,6 +251,8 @@ extern int record_all_packets;
 
 extern RecordType* script_id;
 extern TableType* id_table;
+extern RecordType* record_field;
+extern TableType* record_field_table;
 
 extern StringVal* cmd_line_bpf_filter;
 

src/Type.cc

@@ -987,6 +987,18 @@ BroType* RecordType::FieldType(int field) const
 		}
 	}
 
+Val* RecordType::FieldDefault(int field) const
+	{
+	const TypeDecl* td = FieldDecl(field);
+
+	if ( ! td->attrs )
+		return false;
+
+	const Attr* def_attr = td->attrs->FindAttr(ATTR_DEFAULT);
+
+	return def_attr ? def_attr->AttrExpr()->Eval(0) : 0;
+	}
+
 int RecordType::FieldOffset(const char* field) const
 	{
 	if ( types )

src/Type.h

@@ -448,6 +448,7 @@ public:
 	int HasField(const char* field) const;
 	BroType* FieldType(const char* field) const;
 	BroType* FieldType(int field) const;
+	Val* FieldDefault(int field) const; // Ref's the returned value; 0 if none.
 
 	// A field's offset is its position in the type_decl_list,
 	// starting at 0.  Returns negative if the field doesn't exist.

src/Val.cc

@@ -2935,11 +2935,7 @@ Val* RecordVal::LookupWithDefault(int field) const
 	if ( val )
 		return val->Ref();
 
-	// Check for &default.
+	return record_type->FieldDefault(field);
-	const Attr* def_attr =
-		record_type->FieldDecl(field)->attrs->FindAttr(ATTR_DEFAULT);
-
-	return def_attr ? def_attr->AttrExpr()->Eval(0) : 0;
 	}
 
 RecordVal* RecordVal::CoerceTo(const RecordType* t, Val* aggr) const

src/bro.bif

@@ -1657,6 +1657,44 @@ function global_ids%(%): id_table
 	return ids;
 	%}
 
+function record_fields%(rec: any%): record_field_table
+	%{
+	TableVal* fields = new TableVal(record_field_table);
+
+	RecordVal* rv = rec->AsRecordVal();
+	RecordType* rt = rv->Type()->AsRecordType();
+
+	if ( rt->Tag() != TYPE_RECORD )
+		{
+		reporter->Error("non-record passed to record_fields");
+		return fields;
+		}
+
+	for ( int i = 0; i < rt->NumFields(); ++i )
+		{
+		BroType* ft = rt->FieldType(i);
+		TypeDecl* fd = rt->FieldDecl(i);
+		Val* fv = rv->Lookup(i);
+
+		if ( fv )
+			Ref(fv);
+
+		bool logged = (fd->attrs && fd->FindAttr(ATTR_LOG) != 0);
+
+		RecordVal* nr = new RecordVal(record_field);
+		nr->Assign(0, new StringVal(type_name(rt->Tag())));
+		nr->Assign(1, new Val(logged, TYPE_BOOL));
+		nr->Assign(2, fv);
+		nr->Assign(3, rt->FieldDefault(i));
+
+		Val* field_name = new StringVal(rt->FieldName(i));
+		fields->Assign(field_name, nr);
+		Unref(field_name);
+		}
+
+	return fields;
+	%}
+
 %%{
 #include "Anon.h"
 %%}

testing/btest/Baseline/bifs.records_fields/out

@@ -0,0 +1,8 @@
+[a=42, b=<uninitialized>, c=<uninitialized>, d=Bar]
+{
+[b] = [type_name=record, log=F, value=<uninitialized>, default_val=Foo],
+[d] = [type_name=record, log=T, value=Bar, default_val=<uninitialized>],
+[c] = [type_name=record, log=F, value=<uninitialized>, default_val=<uninitialized>],
+[a] = [type_name=record, log=F, value=42, default_val=<uninitialized>]
+}
+F

testing/btest/bifs/records_fields.bro

@@ -0,0 +1,20 @@
+#
+# @TEST-EXEC: bro %INPUT >out
+# @TEST-EXEC: btest-diff out
+
+type r: record {
+	a: count;
+	b: string &default="Foo";
+	c: double &optional;
+	d: string &log;
+};
+
+event bro_init()
+{
+    local x: r = [$a=42, $d="Bar"];
+    print x;
+    local t: record_field_table;
+    t = record_fields(x);
+    print t;
+    print t["c"]?$value;
+}