feat: Added endianness option to readerHEADmaster

The file reader class can now support either endianness to read in,
and will convert to the native endianness

4 files changed, 62 insertions, 23 deletions

diff --git a/src/PNGImage.cpp b/src/PNGImage.cpp
index 9ba7404..9ab0751 100644
--- a/src/PNGImage.cpp
+++ b/src/PNGImage.cpp
@@ -1,4 +1,5 @@
 #include "PNGImage.h"
+#include "reader.h"
 #include "zlib.h"
 #include "debug.h"
 
@@ -9,6 +10,7 @@
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <endian.h>
 #include <iostream>
 #include <memory>
 #include <stdexcept>
@@ -49,7 +51,7 @@ namespace TehImage
 
 	int PNGImage::readFromFile(std::string filename)
 	{
-		std::unique_ptr<Reader> readerMem(new Reader(filename));
+		std::unique_ptr<Reader> readerMem(new Reader(filename, FileEndianness::BIG));
 		reader = readerMem.get();
 	
 		char signature[8];
diff --git a/src/PNGImage.h b/src/PNGImage.h
index 3c1bf1f..a5d8f3a 100644
--- a/src/PNGImage.h
+++ b/src/PNGImage.h
@@ -19,10 +19,6 @@ namespace TehImage
 
 	class PNGImage : public Image
 	{
-	private:
-		ZLibInflator zlib;
-		uint8_t* idatData;
-		unsigned long idatDataSize;
 	public:
 		PNGImage();
 		~PNGImage();
@@ -64,6 +60,10 @@ namespace TehImage
 		CHUNK_READER(IDAT);
 		CHUNK_READER(IEND);
 
+		ZLibInflator zlib;
+		uint8_t* idatData;
+		unsigned long idatDataSize;
+
 		bool end = false;
 
 		Reader *reader;
diff --git a/src/reader.cpp b/src/reader.cpp
index f8b053f..f0b19ae 100644
--- a/src/reader.cpp
+++ b/src/reader.cpp
@@ -11,11 +11,12 @@
 namespace TehImage
 {
 
-	Reader::Reader(std::string filename)
+	Reader::Reader(std::string filename, FileEndianness fileEndianness)
 	{
 		file = fopen(filename.c_str(), "rb");
 		refreshBuffer();
 		ready = true;
+		this->fileEndianness = fileEndianness;
 	}
 	Reader::~Reader()
 	{
@@ -36,6 +37,24 @@ namespace TehImage
 		pos = 0;
 	}
 
+	void Reader::convertEndian(uint8_t* out, size_t bytes)
+	{
+		constexpr bool LE = std::endian::native == std::endian::little;
+		constexpr bool BE = !LE;
+		if(fileEndianness == NO_CONVERT || (fileEndianness == BIG && BE) || (fileEndianness == LITTLE && LE))
+		{
+			for(int i = 0; i < bytes; i++)
+			{
+				out[i] = readByte();
+			}
+			return;
+		}
+		for(int i = 0; i < bytes; i++)
+		{
+			out[bytes - 1 - i] = readByte();
+		}
+	}
+
 	template<> uint8_t Reader::readData<uint8_t>()
 	{
 		return readByte();
@@ -44,33 +63,36 @@ namespace TehImage
 	template<> uint16_t Reader::readData<uint16_t>()
 	{
 		uint16_t num = 0;
-		for(int i = 0; i < 2; i++)
-		{
-			num += readByte() << (8 * (1-i));
-		}
+		convertEndian((uint8_t*)&num, 2);
+		// for(int i = 0; i < 2; i++)
+		// {
+		// 	num += readByte() << (8 * (1-i));
+		// }
 		return num;
 	}
 
 	template<> uint32_t Reader::readData<uint32_t>()
 	{
 		uint32_t num = 0;
-		for(int i = 0; i < 4; i++)
-		{
-			uint8_t byte = readByte();
-			debug(std::cout << std::hex << 0+byte << " ");
-			num += byte << (8 * (3-i));
-		}
-		debug(std::cout << std::dec << std::endl);
+		convertEndian((uint8_t*)&num, 4);
+		// for(int i = 0; i < 4; i++)
+		// {
+		// 	// uint8_t byte = readByte();
+		// 	// debug(std::cout << std::hex << 0+byte << " ");
+		// 	num += ((uint8_t) readByte()) << (8 * (3-i));
+		// }
+		// // debug(std::cout << std::dec << std::endl);
 		return num;
 	}
 
 	template<> uint64_t Reader::readData<uint64_t>()
 	{
 		uint64_t num = 0;
-		for(int i = 0; i < 8; i++)
-		{
-			num += readByte() << (8 * (7-i));
-		}
+		convertEndian((uint8_t*)&num, 8);
+		// for(int i = 0; i < 8; i++)
+		// {
+		// 	num += readByte() << (8 * (7-i));
+		// }
 		return num;
 	}
 
diff --git a/src/reader.h b/src/reader.h
index a4f913c..bb181e6 100644
--- a/src/reader.h
+++ b/src/reader.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <cstddef>
+#include <cstdint>
 #include <cstdio>
 #include <string>
 
@@ -8,12 +9,18 @@
 
 namespace TehImage
 {
-
+	enum FileEndianness
+	{
+		NO_CONVERT,
+		LITTLE,
+		BIG
+	};
+	
 	class Reader
 	{
 	public:
 		//Bytes are big endian
-		Reader(std::string file);
+		Reader(std::string file, FileEndianness fileEndianness);
 		~Reader();
 
 		template <typename T>
@@ -31,8 +38,16 @@ namespace TehImage
 		size_t pos;
 		FILE* file;
 		bool ready = false;
+		FileEndianness fileEndianness;
 
 		void refreshBuffer();
+		void convertEndian(uint8_t* out, size_t bytes);
 	};
 
+	// template <typename T>
+	// T Reader::readData()
+	// {
+	// 	T num = 0;
+	// 	convertEndian((uint8_t*)&num, sizeof(T));
+	// }
 }