1 files changed, 123 insertions, 0 deletions
diff --git a/Source/Core/DiscIO/DiscUtils.cpp b/Source/Core/DiscIO/DiscUtils.cpp
new file mode 100644
index 0000000000..1919a1d6e5
--- /dev/null
+++ b/Source/Core/DiscIO/DiscUtils.cpp
@@ -0,0 +1,123 @@
+// Copyright 2021 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "DiscIO/DiscUtils.h"
+
+#include <algorithm>
+#include <locale>
+#include <optional>
+#include <string>
+
+#include <fmt/format.h>
+
+#include "Common/CommonTypes.h"
+#include "DiscIO/Volume.h"
+
+namespace DiscIO
+{
+std::string NameForPartitionType(u32 partition_type, bool include_prefix)
+{
+  switch (partition_type)
+  {
+  case PARTITION_DATA:
+    return "DATA";
+  case PARTITION_UPDATE:
+    return "UPDATE";
+  case PARTITION_CHANNEL:
+    return "CHANNEL";
+  case PARTITION_INSTALL:
+    // wit doesn't recognize the name "INSTALL", so we can't use it when naming partition folders
+    if (!include_prefix)
+      return "INSTALL";
+    [[fallthrough]];
+  default:
+    const std::string type_as_game_id{static_cast<char>((partition_type >> 24) & 0xFF),
+                                      static_cast<char>((partition_type >> 16) & 0xFF),
+                                      static_cast<char>((partition_type >> 8) & 0xFF),
+                                      static_cast<char>(partition_type & 0xFF)};
+    if (std::all_of(type_as_game_id.cbegin(), type_as_game_id.cend(),
+                    [](char c) { return std::isalnum(c, std::locale::classic()); }))
+    {
+      return include_prefix ? "P-" + type_as_game_id : type_as_game_id;
+    }
+
+    return fmt::format(include_prefix ? "P{}" : "{}", partition_type);
+  }
+}
+
+std::optional<u64> GetApploaderSize(const Volume& volume, const Partition& partition)
+{
+  constexpr u64 header_size = 0x20;
+  const std::optional<u32> apploader_size = volume.ReadSwapped<u32>(0x2440 + 0x14, partition);
+  const std::optional<u32> trailer_size = volume.ReadSwapped<u32>(0x2440 + 0x18, partition);
+  if (!apploader_size || !trailer_size)
+    return std::nullopt;
+
+  return header_size + *apploader_size + *trailer_size;
+}
+
+std::optional<u64> GetBootDOLOffset(const Volume& volume, const Partition& partition)
+{
+  const Platform volume_type = volume.GetVolumeType();
+  if (!IsDisc(volume_type))
+    return std::nullopt;
+
+  std::optional<u64> dol_offset = volume.ReadSwappedAndShifted(0x420, partition);
+
+  // Datel AR disc has 0x00000000 as the offset (invalid) and doesn't use it in the AppLoader.
+  if (dol_offset && *dol_offset == 0)
+    dol_offset.reset();
+
+  return dol_offset;
+}
+
+std::optional<u32> GetBootDOLSize(const Volume& volume, const Partition& partition, u64 dol_offset)
+{
+  if (!IsDisc(volume.GetVolumeType()))
+    return std::nullopt;
+
+  u32 dol_size = 0;
+
+  // Iterate through the 7 code segments
+  for (size_t i = 0; i < 7; i++)
+  {
+    const std::optional<u32> offset = volume.ReadSwapped<u32>(dol_offset + 0x00 + i * 4, partition);
+    const std::optional<u32> size = volume.ReadSwapped<u32>(dol_offset + 0x90 + i * 4, partition);
+    if (!offset || !size)
+      return {};
+    dol_size = std::max(*offset + *size, dol_size);
+  }
+
+  // Iterate through the 11 data segments
+  for (size_t i = 0; i < 11; i++)
+  {
+    const std::optional<u32> offset = volume.ReadSwapped<u32>(dol_offset + 0x1c + i * 4, partition);
+    const std::optional<u32> size = volume.ReadSwapped<u32>(dol_offset + 0xac + i * 4, partition);
+    if (!offset || !size)
+      return {};
+    dol_size = std::max(*offset + *size, dol_size);
+  }
+
+  return dol_size;
+}
+
+std::optional<u64> GetFSTOffset(const Volume& volume, const Partition& partition)
+{
+  const Platform volume_type = volume.GetVolumeType();
+  if (!IsDisc(volume_type))
+    return std::nullopt;
+
+  return volume.ReadSwappedAndShifted(0x424, partition);
+}
+
+std::optional<u64> GetFSTSize(const Volume& volume, const Partition& partition)
+{
+  const Platform volume_type = volume.GetVolumeType();
+  if (!IsDisc(volume_type))
+    return std::nullopt;
+
+  return volume.ReadSwappedAndShifted(0x428, partition);
+}
+
+}  // namespace DiscIO