From 09fc39e2e550c0a6cc303c9ab2aecdb021665b4c Mon Sep 17 00:00:00 2001
From: "Admiral H. Curtiss" <pikachu025@gmail.com>
Date: Wed, 22 Sep 2021 05:43:05 +0200
Subject: [PATCH] DiscIO: Add CreateDisc/WAD/Volume() overloads that take a
 BlobReader directly.

---
 Source/Core/DiscIO/Volume.cpp | 42 +++++++++++++++++++++++------------
 Source/Core/DiscIO/Volume.h   |  3 +++
 2 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/Source/Core/DiscIO/Volume.cpp b/Source/Core/DiscIO/Volume.cpp
index c1b1400876..bf7ef4e019 100644
--- a/Source/Core/DiscIO/Volume.cpp
+++ b/Source/Core/DiscIO/Volume.cpp
@@ -85,8 +85,11 @@ std::map<Language, std::string> Volume::ReadWiiNames(const std::vector<char16_t>
   return names;
 }
 
-static std::unique_ptr<VolumeDisc> CreateDisc(std::unique_ptr<BlobReader>& reader)
+static std::unique_ptr<VolumeDisc> TryCreateDisc(std::unique_ptr<BlobReader>& reader)
 {
+  if (!reader)
+    return nullptr;
+
   if (reader->ReadSwapped<u32>(0x18) == WII_DISC_MAGIC)
     return std::make_unique<VolumeWii>(std::move(reader));
 
@@ -97,14 +100,21 @@ static std::unique_ptr<VolumeDisc> CreateDisc(std::unique_ptr<BlobReader>& reade
   return nullptr;
 }
 
-std::unique_ptr<VolumeDisc> CreateDisc(const std::string& path)
+std::unique_ptr<VolumeDisc> CreateDisc(std::unique_ptr<BlobReader> reader)
 {
-  std::unique_ptr<BlobReader> reader(CreateBlobReader(path));
-  return reader ? CreateDisc(reader) : nullptr;
+  return TryCreateDisc(reader);
 }
 
-static std::unique_ptr<VolumeWAD> CreateWAD(std::unique_ptr<BlobReader>& reader)
+std::unique_ptr<VolumeDisc> CreateDisc(const std::string& path)
 {
+  return CreateDisc(CreateBlobReader(path));
+}
+
+static std::unique_ptr<VolumeWAD> TryCreateWAD(std::unique_ptr<BlobReader>& reader)
+{
+  if (!reader)
+    return nullptr;
+
   // Check for WAD
   // 0x206962 for boot2 wads
   const std::optional<u32> wad_magic = reader->ReadSwapped<u32>(0x02);
@@ -115,27 +125,31 @@ static std::unique_ptr<VolumeWAD> CreateWAD(std::unique_ptr<BlobReader>& reader)
   return nullptr;
 }
 
-std::unique_ptr<VolumeWAD> CreateWAD(const std::string& path)
+std::unique_ptr<VolumeWAD> CreateWAD(std::unique_ptr<BlobReader> reader)
 {
-  std::unique_ptr<BlobReader> reader(CreateBlobReader(path));
-  return reader ? CreateWAD(reader) : nullptr;
+  return TryCreateWAD(reader);
 }
 
-std::unique_ptr<Volume> CreateVolume(const std::string& path)
+std::unique_ptr<VolumeWAD> CreateWAD(const std::string& path)
 {
-  std::unique_ptr<BlobReader> reader(CreateBlobReader(path));
-  if (reader == nullptr)
-    return nullptr;
+  return CreateWAD(CreateBlobReader(path));
+}
 
-  std::unique_ptr<VolumeDisc> disc = CreateDisc(reader);
+std::unique_ptr<Volume> CreateVolume(std::unique_ptr<BlobReader> reader)
+{
+  std::unique_ptr<VolumeDisc> disc = TryCreateDisc(reader);
   if (disc)
     return disc;
 
-  std::unique_ptr<VolumeWAD> wad = CreateWAD(reader);
+  std::unique_ptr<VolumeWAD> wad = TryCreateWAD(reader);
   if (wad)
     return wad;
 
   return nullptr;
 }
 
+std::unique_ptr<Volume> CreateVolume(const std::string& path)
+{
+  return CreateVolume(CreateBlobReader(path));
+}
 }  // namespace DiscIO
diff --git a/Source/Core/DiscIO/Volume.h b/Source/Core/DiscIO/Volume.h
index 9e378bf879..574afd6f83 100644
--- a/Source/Core/DiscIO/Volume.h
+++ b/Source/Core/DiscIO/Volume.h
@@ -182,8 +182,11 @@ protected:
   static const std::vector<u8> INVALID_CERT_CHAIN;
 };
 
+std::unique_ptr<VolumeDisc> CreateDisc(std::unique_ptr<BlobReader> reader);
 std::unique_ptr<VolumeDisc> CreateDisc(const std::string& path);
+std::unique_ptr<VolumeWAD> CreateWAD(std::unique_ptr<BlobReader> reader);
 std::unique_ptr<VolumeWAD> CreateWAD(const std::string& path);
+std::unique_ptr<Volume> CreateVolume(std::unique_ptr<BlobReader> reader);
 std::unique_ptr<Volume> CreateVolume(const std::string& path);
 
 }  // namespace DiscIO