From ef6cd97656e3e8d9d1fc7d9b308624cf0fd95a89 Mon Sep 17 00:00:00 2001
From: Uwe Seimet <48174652+uweseimet@users.noreply.github.com>
Date: Wed, 15 Mar 2023 22:38:44 +0100
Subject: [PATCH] Improve OpenVMS/VAX compatibility (issue #1117) (#1123)

* Set TB, PER and DTE bits in read/write error recovery page

* Fixed typo

* Added unit test

* Comment update
---
 cpp/devices/disk.cpp         |  7 ++++++-
 cpp/test/mocks.h             |  3 ++-
 cpp/test/scsihd_nec_test.cpp | 16 +++++++++++++++-
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/cpp/devices/disk.cpp b/cpp/devices/disk.cpp
index 63574ad3..8649103f 100644
--- a/cpp/devices/disk.cpp
+++ b/cpp/devices/disk.cpp
@@ -396,7 +396,12 @@ void Disk::SetUpModePages(map<int, vector<byte>>& pages, int page, bool changeab
 void Disk::AddErrorPage(map<int, vector<byte>>& pages, bool) const
 {
 	// Retry count is 0, limit time uses internal default value
-	pages[1] = vector<byte>(12);
+	vector<byte> buf(12);
+
+	// TB, PER, DTE (required for OpenVMS/VAX compatibility, see issue #1117)
+	buf[2] = (byte)0x26;
+
+	pages[1] = buf;
 }
 
 void Disk::AddFormatPage(map<int, vector<byte>>& pages, bool changeable) const
diff --git a/cpp/test/mocks.h b/cpp/test/mocks.h
index ef49fa6b..f654054d 100644
--- a/cpp/test/mocks.h
+++ b/cpp/test/mocks.h
@@ -3,7 +3,7 @@
 // SCSI Target Emulator PiSCSI
 // for Raspberry Pi
 //
-// Copyright (C) 2022 Uwe Seimet
+// Copyright (C) 2022-2023 Uwe Seimet
 //
 //---------------------------------------------------------------------------
 
@@ -358,6 +358,7 @@ class MockSCSIHD : public SCSIHD //NOSONAR Ignore inheritance hierarchy depth in
 class MockSCSIHD_NEC : public SCSIHD_NEC //NOSONAR Ignore inheritance hierarchy depth in unit tests
 {
 	FRIEND_TEST(ScsiHdNecTest, SetUpModePages);
+	FRIEND_TEST(ScsiHdNecTest, TestAddErrorPage);
 	FRIEND_TEST(ScsiHdNecTest, TestAddFormatPage);
 	FRIEND_TEST(ScsiHdNecTest, TestAddDrivePage);
 	FRIEND_TEST(PiscsiExecutorTest, ProcessDeviceCmd);
diff --git a/cpp/test/scsihd_nec_test.cpp b/cpp/test/scsihd_nec_test.cpp
index 9ddf9a11..cfff8485 100644
--- a/cpp/test/scsihd_nec_test.cpp
+++ b/cpp/test/scsihd_nec_test.cpp
@@ -3,7 +3,7 @@
 // SCSI Target Emulator PiSCSI
 // for Raspberry Pi
 //
-// Copyright (C) 2022 Uwe Seimet
+// Copyright (C) 2022-2023 Uwe Seimet
 //
 //---------------------------------------------------------------------------
 
@@ -47,6 +47,20 @@ TEST(ScsiHdNecTest, SetUpModePages)
 	ScsiHdNecTest_SetUpModePages(pages);
 }
 
+TEST(ScsiHdNecTest, TestAddErrorPage)
+{
+	map<int, vector<byte>> pages;
+	MockSCSIHD_NEC hd(0);
+
+	hd.SetBlockCount(0x1234);
+	hd.SetReady(true);
+	// Non changeable
+	hd.SetUpModePages(pages, 0x01, false);
+	EXPECT_EQ(1, pages.size()) << "Unexpected number of mode pages";
+	const vector<byte>& page_1 = pages[1];
+	EXPECT_EQ(0x26, to_integer<int>(page_1[2]));
+}
+
 TEST(ScsiHdNecTest, TestAddFormatPage)
 {
 	map<int, vector<byte>> pages;