Initial work on patch list

arm7/source/loader/PatchList.h

@@ -0,0 +1,71 @@
+#pragma once
+#include <memory>
+
+enum class PatchListPatchType : u8
+{
+    Replace,
+    Metafortress
+};
+
+struct PatchListHeaderEntry
+{
+    u32 gameCode;
+    u32 gameVersion : 8;
+    u32 offset : 24;
+};
+
+struct PatchListHeader
+{
+    u32 entryCount;
+    PatchListHeaderEntry headerEntries[1];
+};
+
+union PatchListEntryPatch
+{
+    struct
+    {
+        PatchListPatchType patchType;
+        u8 reserved;
+    } common;
+    struct
+    {
+        PatchListPatchType patchType;
+        u8 reserved;
+        u16 dataLength;
+        u32 address;
+        u8 data[1];
+    } replacePatch;
+    struct
+    {
+        PatchListPatchType patchType;
+        u8 reserved;
+        u16 addressCount;
+        u32 addresses[1];
+    } metafortressPatch;
+};
+
+static_assert(offsetof(PatchListEntryPatch, replacePatch.dataLength) == 2);
+static_assert(offsetof(PatchListEntryPatch, replacePatch.address) == 4);
+static_assert(offsetof(PatchListEntryPatch, replacePatch.data) == 8);
+static_assert(offsetof(PatchListEntryPatch, metafortressPatch.addressCount) == 2);
+static_assert(offsetof(PatchListEntryPatch, metafortressPatch.addresses) == 4);
+
+struct PatchListEntry
+{
+    u16 length;
+    u16 patchCount;
+    PatchListEntryPatch firstPatch;
+};
+
+/// @brief Class representing a patch list.
+class PatchList
+{
+public:
+    PatchList(std::unique_ptr<const u8[]> fileContents)
+        : _fileContents(std::move(fileContents)) { }
+
+    const PatchListEntry* FindEntry(u32 gameCode, u8 gameVersion);
+
+private:
+    std::unique_ptr<const u8[]> _fileContents;
+};