From f3c7e011959f3be924582cde99dcf326d7702094 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Wed, 13 Dec 2023 16:58:12 +0100
Subject: [PATCH] fixed BufferingReader

---
 src/common/filesystem/source/files.cpp            | 2 +-
 src/common/filesystem/source/files_decompress.cpp | 5 +++--
 src/common/filesystem/source/files_internal.h     | 1 +
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/common/filesystem/source/files.cpp b/src/common/filesystem/source/files.cpp
index 87eee970d0..9f0d24fc2b 100644
--- a/src/common/filesystem/source/files.cpp
+++ b/src/common/filesystem/source/files.cpp
@@ -334,7 +334,7 @@ int BufferingReader::FillBuffer(ptrdiff_t newpos)
 		// we have read the entire file, so delete our data provider.
 		baseReader.reset();
 	}
-	return read == newpos - bufferpos ? 0 : -1;
+	return newpos == bufferpos ? 0 : -1;
 }
 
 ptrdiff_t BufferingReader::Seek(ptrdiff_t offset, int origin)
diff --git a/src/common/filesystem/source/files_decompress.cpp b/src/common/filesystem/source/files_decompress.cpp
index 0bbb80c522..8bf681357d 100644
--- a/src/common/filesystem/source/files_decompress.cpp
+++ b/src/common/filesystem/source/files_decompress.cpp
@@ -181,7 +181,7 @@ public:
 		inflateEnd (&Stream);
 	}
 
-	ptrdiff_t Read (void *buffer, ptrdiff_t len) override
+	ptrdiff_t Read (void *buffer, ptrdiff_t olen) override
 	{
 		int err = 0;
 
@@ -190,6 +190,7 @@ public:
 			DecompressionError("File not open");
 			return 0;
 		}
+		auto len = olen;
 		if (len == 0) return 0;
 
 		while (len > 0)
@@ -222,7 +223,7 @@ public:
 			return 0;
 		}
 
-		return len - Stream.avail_out;
+		return olen - Stream.avail_out;
 	}
 
 	void FillBuffer ()
diff --git a/src/common/filesystem/source/files_internal.h b/src/common/filesystem/source/files_internal.h
index 38a28e6e33..f8563eebcb 100644
--- a/src/common/filesystem/source/files_internal.h
+++ b/src/common/filesystem/source/files_internal.h
@@ -42,6 +42,7 @@ public:
 	{
 		Length = base->Length;
 		buf.resize(Length);
+		bufptr = (const char*)buf.data();
 	}
 
 	ptrdiff_t Seek(ptrdiff_t offset, int origin) override;