Update count handling when hitting beginning-of-partition

uweseimet · Dec 8, 2024 · b97aca4 · b97aca4
1 parent 87a5c14
commit b97aca4
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Showing 3 changed files with 16 additions and 11 deletions.
diff --git a/cpp/devices/tape.cpp b/cpp/devices/tape.cpp
@@ -604,7 +604,7 @@ void Tape::WriteMetaData(Tape::object_type type, uint32_t size)
     CheckForWriteError();
 }
 
-SimhMetaData Tape::FindNextObject(object_type type, int64_t requested_count, bool read)
+SimhMetaData Tape::FindNextObject(object_type type, int32_t requested_count, bool read)
 {
     const bool reverse = requested_count < 0;
 
@@ -615,11 +615,11 @@ SimhMetaData Tape::FindNextObject(object_type type, int64_t requested_count, boo
         requested_count = -requested_count;
     }
 
-    int64_t actual_count = 0;
+    int32_t actual_count = 0;
 
     while (true) {
         SimhMetaData meta_data;
-        const auto [scsi_type, length] = ReadSimhMetaData(meta_data, actual_count, reverse);
+        const auto [scsi_type, length] = ReadSimhMetaData(meta_data, reverse);
 
         // Bad data (not recovered) during READ(6)?
         if (read && scsi_type == object_type::block && !length) {
@@ -641,13 +641,17 @@ SimhMetaData Tape::FindNextObject(object_type type, int64_t requested_count, boo
             return meta_data;
         }
 
+        if (scsi_type == object_type::beginning_of_partition) {
+            RaiseBeginningOfPartition(requested_count + 1);
+        }
+
         if (scsi_type == object_type::end_of_partition) {
-            RaiseEndOfPartition(reverse ? -requested_count + actual_count - 1 : actual_count - 1);
+            RaiseEndOfPartition(actual_count);
         }
 
         // End-of-data while spacing over blocks or filemarks
         if (scsi_type == object_type::end_of_data && type != object_type::end_of_data) {
-            RaiseEndOfData(type, reverse ? -requested_count + actual_count - 1 : actual_count - 1);
+            RaiseEndOfData(type, actual_count - 1);
         }
 
         // Terminate while spacing over blocks and a filemark is found
@@ -832,11 +836,11 @@ vector<PbStatistics> Tape::GetStatistics() const
     return statistics;
 }
 
-pair<Tape::object_type, int> Tape::ReadSimhMetaData(SimhMetaData &meta_data, int64_t count, bool reverse)
+pair<Tape::object_type, int> Tape::ReadSimhMetaData(SimhMetaData &meta_data, bool reverse)
 {
     while (true) {
         if (!ReadNextMetaData(meta_data, reverse)) {
-            RaiseBeginningOfPartition(reverse ? -count : count);
+            return {object_type::beginning_of_partition, 0};
         }
 
         switch (meta_data.cls) {

diff --git a/cpp/devices/tape.h b/cpp/devices/tape.h
@@ -68,7 +68,8 @@ class Tape : public StorageDevice, public ScsiStreamCommands
         filemark = 0b001,
         end_of_data = 0b011,
         // SCSI2Pi-specific
-        end_of_partition = -1,
+        beginning_of_partition = -1,
+        end_of_partition = -2
     };
 
     // Commands covered by the SCSI specifications (see https://www.t10.org/drafts.htm)
@@ -85,7 +86,7 @@ class Tape : public StorageDevice, public ScsiStreamCommands
     void Locate(bool);
 
     void WriteMetaData(Tape::object_type, uint32_t = 0);
-    SimhMetaData FindNextObject(Tape::object_type, int64_t, bool);
+    SimhMetaData FindNextObject(Tape::object_type, int32_t, bool);
     bool ReadNextMetaData(SimhMetaData&, bool);
 
     [[noreturn]] void RaiseBeginningOfPartition(int64_t);
@@ -105,7 +106,7 @@ class Tape : public StorageDevice, public ScsiStreamCommands
 
     void ResetPosition();
 
-    pair<Tape::object_type, int> ReadSimhMetaData(SimhMetaData&, int64_t, bool);
+    pair<Tape::object_type, int> ReadSimhMetaData(SimhMetaData&, bool);
     int WriteSimhMetaData(simh_class, uint32_t);
 
     void CheckBlockLength(int);

diff --git a/cpp/test/tape_test.cpp b/cpp/test/tape_test.cpp
@@ -555,7 +555,7 @@ TEST(TapeTest, Space6_simh)
     Dispatch(*tape, scsi_command::request_sense);
     EXPECT_EQ(0b01000000, controller->GetBuffer()[2]) << "EOM must be set";
     EXPECT_EQ(0x80, controller->GetBuffer()[0] & 0x80) << "VALID must be set";
-    EXPECT_EQ(0xffffffffU, GetInt32(controller->GetBuffer(), 3));
+    EXPECT_EQ(0xffU, GetInt32(controller->GetBuffer(), 3));
 
 
     // Write 6 data records (bad and good) and different markers, 1 filemark