From ce23544a159b954158945976c1e5c70f333a94b3 Mon Sep 17 00:00:00 2001
From: Phillip Stephens <antidote.crk@gmail.com>
Date: Fri, 18 Feb 2022 21:32:36 -0800
Subject: [PATCH] Fix CInputStream::Get/ReadBytes not properly updating
 position

---
 Runtime/CInputStream.cpp        | 60 +++++++++++++++------------------
 Runtime/RetroTypes.cpp          |  4 +--
 Runtime/World/CEnvFxManager.cpp |  4 +--
 3 files changed, 31 insertions(+), 37 deletions(-)

diff --git a/Runtime/CInputStream.cpp b/Runtime/CInputStream.cpp
index 1113bc7c8..2c0b450bf 100644
--- a/Runtime/CInputStream.cpp
+++ b/Runtime/CInputStream.cpp
@@ -31,30 +31,29 @@ bool CInputStream::InternalReadNext() {
 bool CInputStream::GrabAnotherBlock() { return InternalReadNext(); }
 
 void CInputStream::Get(u8* dest, u32 len) {
+  u32 readLen = 0;
   x20_bitOffset = 0;
-  u32 offset = 0;
   while (len != 0) {
     u32 blockLen = x8_blockLen - x4_blockOffset;
     if (len < blockLen) {
       blockLen = len;
     }
 
-    if (blockLen == 0) {
-      if (len <= 256) {
-        GrabAnotherBlock();
-      } else {
-        u32 readLen = Read(dest + offset, len);
-        len -= readLen;
-        offset += readLen;
-      }
-    } else {
-      memcpy(dest + offset, x10_ptr + x4_blockOffset, blockLen);
+    if (blockLen != 0) {
+      memcpy(dest + readLen, x10_ptr + x4_blockOffset, blockLen);
       len -= blockLen;
+      readLen += blockLen;
       x4_blockOffset += blockLen;
+    } else if (len > 256) {
+      u32 tmp = Read(dest + readLen, len);
+      len -= tmp;
+      readLen += tmp;
+    } else {
+      GrabAnotherBlock();
     }
   }
 
-  x18_readPosition += offset;
+  x18_readPosition += readLen;
 }
 
 u32 CInputStream::ReadBytes(void* dest, u32 len) {
@@ -66,31 +65,26 @@ u32 CInputStream::ReadBytes(void* dest, u32 len) {
     GrabAnotherBlock();
   }
 
-  u32 curReadLen = 0;
   u32 curLen = len;
+  u32 curReadLen = 0;
 
-  do {
-    while (true) {
-      if (len <= curReadLen) {
-        x18_readPosition += curReadLen;
-        return curReadLen;
-      }
-
-      u32 readCount = x8_blockLen - x4_blockOffset;
-      if (readCount == 0) {
-        break;
-      }
-
-      if (curLen < readCount) {
-        readCount = curLen;
-      }
-
-      memcpy(reinterpret_cast<u8*>(dest) + curReadLen, x10_ptr + x4_blockOffset, readCount);
-      curReadLen += readCount;
-      curLen -= readCount;
+  while (curReadLen < len) {
+    if ((x8_blockLen - x4_blockOffset) == 0 && !InternalReadNext()) {
+      break;
     }
-  } while (InternalReadNext());
 
+    u32 readCount = x8_blockLen - x4_blockOffset;
+    if (curLen < (x8_blockLen - x4_blockOffset)) {
+      readCount = curLen;
+    }
+
+    memcpy(reinterpret_cast<u8*>(dest) + curReadLen, x10_ptr + x4_blockOffset, readCount);
+    curReadLen += readCount;
+    curLen -= readCount;
+    x4_blockOffset += readCount;
+  }
+
+  x18_readPosition += curReadLen;
   return curReadLen;
 }
 
diff --git a/Runtime/RetroTypes.cpp b/Runtime/RetroTypes.cpp
index 45ca652f8..c05f36c11 100644
--- a/Runtime/RetroTypes.cpp
+++ b/Runtime/RetroTypes.cpp
@@ -9,13 +9,13 @@ namespace metaforce {
 logvisor::Module Log("metaforce::RetroTypes::CAssetId");
 
 SObjectTag::SObjectTag(CInputStream& in) {
-  in.ReadBytes(reinterpret_cast<char*>(&type), 4);
+  in.Get(reinterpret_cast<u8*>(&type), 4);
   id = in.Get<CAssetId>();
 }
 
 void SObjectTag::ReadMLVL(CInputStream& in) {
   id = in.Get<CAssetId>();
-  in.ReadBytes(reinterpret_cast<char*>(&type), 4);
+  in.Get(reinterpret_cast<u8*>(&type), 4);
 }
 
 CAssetId::CAssetId(CInputStream& in) {
diff --git a/Runtime/World/CEnvFxManager.cpp b/Runtime/World/CEnvFxManager.cpp
index 53a9e1dce..5e79fd098 100644
--- a/Runtime/World/CEnvFxManager.cpp
+++ b/Runtime/World/CEnvFxManager.cpp
@@ -599,9 +599,9 @@ void CEnvFxManager::Cleanup() {
 void CEnvFxManager::Initialize() {
   const SObjectTag* tag = g_ResFactory->GetResourceIdByName("DUMB_SnowForces");
   std::unique_ptr<u8[]> data = g_ResFactory->LoadResourceSync(*tag);
-  athena::io::MemoryReader r(data.get(), 2048);
+  CMemoryInStream r(data.get(), 2048, CMemoryInStream::EOwnerShip::NotOwned);
   for (int i = 0; i < 256; ++i)
-    g_SnowForces.push_back(r.readVec2fBig());
+    g_SnowForces.push_back(r.Get<zeus::CVector2f>());
 }
 
 } // namespace metaforce