Add IVFC parser

src/core/fs/ivfc.cpp

@@ -0,0 +1,78 @@
+#include "fs/ivfc.hpp"
+
+namespace IVFC {
+
+    size_t parseIVFC(uintptr_t ivfcStart, IVFC& ivfc) {
+        uintptr_t ivfcPointer = ivfcStart;
+        std::string magicIVFC((char*)ivfcPointer, 4);
+        ivfcPointer += 4;
+
+        if (magicIVFC != "IVFC") {
+            printf("Invalid IVFC magic: %s\n", magicIVFC.c_str());
+            return 0;
+        }
+
+        uint32_t magicIdentifier = *(u32*)ivfcPointer;
+        ivfcPointer += 4;
+
+        // RomFS IVFC uses 0x10000, DISA/DIFF IVFC uses 0x20000 here
+        if (magicIdentifier != 0x10000 && magicIdentifier != 0x20000) {
+            printf("Invalid IVFC magic identifier: %08X\n", magicIdentifier);
+            return 0;
+        }
+
+        if (magicIdentifier == 0x10000) {
+            ivfc.masterHashSize = *(u32*)ivfcPointer;
+            ivfcPointer += 4;
+            // RomFS IVFC uses 3 levels
+            ivfc.levels.resize(3);
+        } else {
+            ivfc.masterHashSize = *(u64*)ivfcPointer;
+            ivfcPointer += 8;
+            // DISA/DIFF IVFC uses 4 levels
+            ivfc.levels.resize(4);
+        }
+
+        for (size_t i = 0; i < ivfc.levels.size(); i++) {
+            IVFCLevel level;
+            
+            level.logicalOffset = *(u64*)ivfcPointer;
+            ivfcPointer += 8;
+
+            level.size = *(u64*)ivfcPointer;
+            ivfcPointer += 8;
+
+            // This field is in log2
+            level.blockSize = 1 << *(u32*)ivfcPointer;
+            ivfcPointer += 4;
+
+            // Skip 4 reserved bytes
+            ivfcPointer += 4;
+
+            ivfc.levels[i] = level;
+        }
+
+        u64 ivfcDescriptorSize = *(u64*)ivfcPointer;
+        ivfcPointer += 8;
+
+        uintptr_t ivfcActualSize = ivfcPointer - ivfcStart;
+
+        // According to 3DBrew, this is usually the case but not guaranteed
+        if (ivfcActualSize != ivfcDescriptorSize) {
+            printf("IVFC descriptor size mismatch: %lx != %lx\n", ivfcActualSize, ivfcDescriptorSize);
+        }
+
+        if (magicIdentifier == 0x10000 && ivfcActualSize != 0x5C) {
+            // This is always 0x5C bytes long
+            printf("Invalid IVFC size: %08x\n", (u32)ivfcActualSize);
+            return 0;
+        } else if (magicIdentifier == 0x20000 && ivfcActualSize != 0x78) {
+            // This is always 0x78 bytes long
+            printf("Invalid IVFC size: %08x\n", (u32)ivfcActualSize);
+            return 0;
+        }
+
+        return ivfcActualSize;
+    }
+
+} // namespace IVFC

src/core/fs/romfs.cpp

@@ -0,0 +1,21 @@
+#include "fs/romfs.hpp"
+#include "fs/ivfc.hpp"
+#include <cstdio>
+
+namespace RomFS {
+
+    RomFSNode parseRomFSTree(uintptr_t romFS, u64 romFSSize) {
+        RomFSNode root;
+
+        IVFC::IVFC ivfc;
+        size_t ivfcSize = IVFC::parseIVFC((uintptr_t)romFS, ivfc);
+
+        if (ivfcSize == 0) {
+            printf("Failed to parse IVFC\n");
+            return {};
+        }
+
+        return root;
+    }
+
+} // namespace RomFS