Fix &raw_output and enable_raw_output interpretation of NUL characters

When using a `print` statement to write to a file that has raw output
enabled, NUL characters in string are no longer interpreted into "\0",
no newline is appended afterwards, and each argument to `print` is
written to the file without any additional separation.

(Re)Assigning to identifiers with the &raw_output attribute should also
now correctly apply the attribute to the file value being assigned.

Note that the write_file BiF should already be capable of raw string
data to a file, expect it bypasses the print_hook event.

Addresses #474

src/Desc.cc

@@ -173,6 +173,10 @@ void ODesc::AddCS(const char* s)
 void ODesc::AddBytes(const BroString* s)
 	{
 	if ( IsReadable() )
+		{
+		if ( Style() == RAW_STYLE )
+			AddBytes(reinterpret_cast<const char*>(s->Bytes()), s->Len());
+		else
 			{
 			int render_style = BroString::EXPANDED_STRING;
 			if ( Style() == ALTERNATIVE_STYLE )
@@ -184,6 +188,7 @@ void ODesc::AddBytes(const BroString* s)
 			Add(str);
 			delete [] str;
 			}
+		}
 	else
 		{
 		Add(s->Len());

src/Desc.h

@@ -17,6 +17,7 @@ typedef enum {
 typedef enum {
 	STANDARD_STYLE,
 	ALTERNATIVE_STYLE,
+	RAW_STYLE,
 } desc_style;
 
 class BroFile;

src/Expr.cc

@@ -319,6 +319,8 @@ void NameExpr::Assign(Frame* f, Val* v, Opcode op)
 		id->SetVal(v, op);
 	else
 		f->SetElement(id->Offset(), v);
+	if ( v->Type()->Tag() == TYPE_FILE )
+		v->AsFile()->SetAttrs(id->Attrs());
 	}
 
 int NameExpr::IsPure() const

src/RemoteSerializer.cc

@@ -2385,7 +2385,7 @@ bool RemoteSerializer::FlushPrintBuffer(Peer* p)
 	return true;
 	}
 
-bool RemoteSerializer::SendPrintHookEvent(BroFile* f, const char* txt)
+bool RemoteSerializer::SendPrintHookEvent(BroFile* f, const char* txt, size_t len)
 	{
 	loop_over_list(peers, i)
 		{
@@ -2398,8 +2398,6 @@ bool RemoteSerializer::SendPrintHookEvent(BroFile* f, const char* txt)
 		if ( ! fname )
 			continue; // not a managed file.
 
-		size_t len = strlen(txt);
-
 		// We cut off everything after the max buffer size.  That
 		// makes the code a bit easier, and we shouldn't have such
 		// long lines anyway.

src/RemoteSerializer.h

@@ -95,7 +95,7 @@ public:
 	bool SendPing(PeerID peer, uint32 seq);
 
 	// Broadcast remote print.
-	bool SendPrintHookEvent(BroFile* f, const char* txt);
+	bool SendPrintHookEvent(BroFile* f, const char* txt, size_t len);
 
 	// Send a request to create a writer on a remote side.
 	bool SendLogCreateWriter(PeerID peer, EnumVal* id, EnumVal* writer, string path, int num_fields, const LogField* const * fields);

src/Stmt.cc

@@ -277,9 +277,20 @@ Val* PrintStmt::DoExec(val_list* vals, stmt_flow_type& /* flow */) const
 
 	bool ph = print_hook && f->IsPrintHookEnabled();
 
-	desc_style style = f->IsRawOutput() ? ALTERNATIVE_STYLE : STANDARD_STYLE;
+	desc_style style = f->IsRawOutput() ? RAW_STYLE : STANDARD_STYLE;
 
 	if ( ! (suppress_local_output && ph) )
+		{
+		if ( f->IsRawOutput() )
+			{
+			ODesc d(DESC_READABLE);
+			d.SetFlush(0);
+			d.SetStyle(style);
+
+			PrintVals(&d, vals, offset);
+			f->Write(d.Description(), d.Len());
+			}
+		else
 			{
 			ODesc d(DESC_READABLE, f);
 			d.SetFlush(0);
@@ -288,6 +299,7 @@ Val* PrintStmt::DoExec(val_list* vals, stmt_flow_type& /* flow */) const
 			PrintVals(&d, vals, offset);
 			f->Write("\n", 1);
 			}
+		}
 
 	if ( ph )
 		{
@@ -300,14 +312,14 @@ Val* PrintStmt::DoExec(val_list* vals, stmt_flow_type& /* flow */) const
 			val_list* vl = new val_list(2);
 			::Ref(f);
 			vl->append(new Val(f));
-			vl->append(new StringVal(d.Description()));
+			vl->append(new StringVal(d.Len(), d.Description()));
 
 			// Note, this doesn't do remote printing.
 			mgr.Dispatch(new Event(print_hook, vl), true);
 			}
 
 		if ( remote_serializer )
-			remote_serializer->SendPrintHookEvent(f, d.Description());
+			remote_serializer->SendPrintHookEvent(f, d.Description(), d.Len());
 		}
 
 	return 0;

src/Val.cc

@@ -3567,7 +3567,7 @@ void describe_vals(const val_list* vals, ODesc* d, int offset)
 
 	for ( int i = offset; i < vals->length(); ++i )
 		{
-		if ( i > offset && d->IsReadable() )
+		if ( i > offset && d->IsReadable() && d->Style() != RAW_STYLE )
 			d->Add(", ");
 
 		(*vals)[i]->Describe(d);

testing/btest/Baseline/bifs.enable_raw_output/output

@@ -0,0 +1 @@
+helloXworldhi

testing/btest/Baseline/language.raw_output_attr-2/output

@@ -0,0 +1 @@
+helloXworldhi

testing/btest/Baseline/language.raw_output_attr/output

@@ -0,0 +1 @@
+helloXworldhi

testing/btest/bifs/enable_raw_output.test

@@ -0,0 +1,23 @@
+# Files which enable raw output via the BiF shouldn't interpret NUL characters
+# in strings that are `print`ed to it.
+
+# @TEST-EXEC: bro %INPUT
+# @TEST-EXEC: tr '\000' 'X' <myfile >output
+# @TEST-EXEC: btest-diff output
+# @TEST-EXEC: cmp myfile hookfile
+
+event bro_init()
+    {
+    local myfile: file;
+    myfile = open("myfile");
+    enable_raw_output(myfile);
+    print myfile, "hello\x00world", "hi";
+    close(myfile);
+    }
+
+event print_hook(f: file, s: string)
+    {
+    local hookfile = open("hookfile");
+    write_file(hookfile, s);
+    close(hookfile);
+    }

testing/btest/language/raw_output_attr.test

@@ -0,0 +1,43 @@
+# Files with the &raw_output attribute shouldn't interpret NUL characters
+# in strings that are `print`ed to it.
+
+# @TEST-EXEC: bro %INPUT
+# @TEST-EXEC: tr '\000' 'X' <myfile >output
+# @TEST-EXEC: btest-diff output
+# @TEST-EXEC: cmp myfile hookfile
+
+# first check local variable of file type w/ &raw_output
+
+event bro_init()
+    {
+    local myfile: file &raw_output;
+    myfile = open("myfile");
+    print myfile, "hello\x00world", "hi";
+    close(myfile);
+    }
+
+event print_hook(f: file, s: string)
+    {
+    local hookfile = open("hookfile");
+    write_file(hookfile, s);
+    close(hookfile);
+    }
+
+# @TEST-START-NEXT
+# now check global variables of file type w/ &raw_output
+
+global myfile: file &raw_output;
+
+event bro_init()
+    {
+    myfile = open("myfile");
+    print myfile, "hello\x00world", "hi";
+    close(myfile);
+    }
+
+event print_hook(f: file, s: string)
+    {
+    local hookfile = open("hookfile");
+    write_file(hookfile, s);
+    close(hookfile);
+    }