Pick up changes from the Samba repository:

  commit 59d530c0b692dae41ea271bfdb473f212615041b
  Author: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
  Date:   Tue Mar 1 14:18:52 2016 +1300

    ndr: Use ndr_steal to avoid long lists

    When pulling complex structures like nt-acls, a long list of tokens may
    be produced. By removing tokens along the way with ndr_token_steal,
    future calls to retrieve from the token list are not as expensive.

    Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet@samba.org>
    Reviewed-by: Garming Sam <garming@catalyst.net.nz>

  commit 9af628a488d2b628e6c33917be7030602eeb5fde
  Author: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
  Date:   Fri Feb 26 17:01:37 2016 +1300

    ndr: avoid unnecessary searches of token list

    When pulling complex structures like nt-acls, a long list of tokens
    may be produced. This change means the token list won't be walked in the
    buffers case if the switch value is not needed.

    Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet@samba.org>
    Reviewed-by: Garming Sam <garming@catalyst.net.nz>

Change-Id: I0e0ce345e5184e0cd180b0079dd693a7ed3f31ef
Reviewed-on: https://code.wireshark.org/review/16736
Reviewed-by: Guy Harris <guy@alum.mit.edu>

1 files changed, 42 insertions, 15 deletions

diff --git a/tools/pidl/lib/Parse/Pidl/Samba4/NDR/Parser.pm b/tools/pidl/lib/Parse/Pidl/Samba4/NDR/Parser.pm
index 09456c2325..94f4855dd6 100644
--- a/tools/pidl/lib/Parse/Pidl/Samba4/NDR/Parser.pm
+++ b/tools/pidl/lib/Parse/Pidl/Samba4/NDR/Parser.pm
@@ -321,6 +321,25 @@ sub check_null_pointer($$$$)
 	}
 }
 
+sub is_deferred_switch_non_empty($)
+{
+	# 1 if there needs to be a deferred branch in an ndr_pull/push,
+	# 0 otherwise.
+	my ($e) = @_;
+	my $have_default = 0;
+	foreach my $el (@{$e->{ELEMENTS}}) {
+		if ($el->{CASE} eq "default") {
+			$have_default = 1;
+		}
+		if ($el->{TYPE} ne "EMPTY") {
+			if (ContainsDeferred($el, $el->{LEVELS}[0])) {
+				return 1;
+			}
+		}
+	}
+	return ! $have_default;
+}
+
 sub ParseArrayPullGetSize($$$$$$)
 {
 	my ($self,$e,$l,$ndr,$var_name,$env) = @_;
@@ -1923,11 +1942,13 @@ sub ParseUnionPush($$$$)
 	$self->ParseUnionPushPrimitives($e, $ndr, $varname);
 	$self->deindent;
 	$self->pidl("}");
-	$self->pidl("if (ndr_flags & NDR_BUFFERS) {");
-	$self->indent;
-	$self->ParseUnionPushDeferred($e, $ndr, $varname);
-	$self->deindent;
-	$self->pidl("}");
+        if (is_deferred_switch_non_empty($e)) {
+                $self->pidl("if (ndr_flags & NDR_BUFFERS) {");
+                $self->indent;
+                $self->ParseUnionPushDeferred($e, $ndr, $varname);
+                $self->deindent;
+                $self->pidl("}");
+        }
 	$self->end_flags($e, $ndr);
 }
 
@@ -2072,7 +2093,7 @@ sub ParseUnionPull($$$$)
 {
 	my ($self,$e,$ndr,$varname) = @_;
 	my $switch_type = $e->{SWITCH_TYPE};
-
+        my $needs_deferred_switch = is_deferred_switch_non_empty($e);
 	$self->pidl("uint32_t level;");
 	if (defined($switch_type)) {
 		if (Parse::Pidl::Typelist::typeIs($switch_type, "ENUM")) {
@@ -2093,21 +2114,27 @@ sub ParseUnionPull($$$$)
 
 	$self->start_flags($e, $ndr);
 
-	$self->pidl("level = ndr_pull_get_switch_value($ndr, $varname);");
-
 	$self->pidl("NDR_PULL_CHECK_FLAGS(ndr, ndr_flags);");
 	$self->pidl("if (ndr_flags & NDR_SCALARS) {");
 	$self->indent;
+	if (! $needs_deferred_switch) {
+		$self->pidl("/* This token is not used again */");
+		$self->pidl("level = ndr_pull_steal_switch_value($ndr, $varname);");
+	} else {
+		$self->pidl("level = ndr_pull_get_switch_value($ndr, $varname);");
+	}
 	$self->ParseUnionPullPrimitives($e,$ndr,$varname,$switch_type);
 	$self->deindent;
 	$self->pidl("}");
-
-	$self->pidl("if (ndr_flags & NDR_BUFFERS) {");
-	$self->indent;
-	$self->ParseUnionPullDeferred($e,$ndr,$varname);
-	$self->deindent;
-	$self->pidl("}");
-
+	if ($needs_deferred_switch) {
+		$self->pidl("if (ndr_flags & NDR_BUFFERS) {");
+		$self->indent;
+		$self->pidl("/* The token is not needed after this. */");
+		$self->pidl("level = ndr_pull_steal_switch_value($ndr, $varname);");
+		$self->ParseUnionPullDeferred($e,$ndr,$varname);
+		$self->deindent;
+		$self->pidl("}");
+	}
 	$self->add_deferred();
 
 	$self->end_flags($e, $ndr);