Merge pull request #105178 from bruvzg/endianess_notes

Remove misleading and incorrect notes about endianness. Fix FileAccess and StreamPeer not doing what name suggests.

core/io/file_access.cpp

@@ -313,9 +313,15 @@ uint16_t FileAccess::get_16() const {
 	uint16_t data = 0;
 	get_buffer(reinterpret_cast<uint8_t *>(&data), sizeof(uint16_t));
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		data = BSWAP16(data);
+	}
+#else
 	if (big_endian) {
 		data = BSWAP16(data);
 	}
+#endif
 
 	return data;
 }
@@ -324,9 +330,15 @@ uint32_t FileAccess::get_32() const {
 	uint32_t data = 0;
 	get_buffer(reinterpret_cast<uint8_t *>(&data), sizeof(uint32_t));
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		data = BSWAP32(data);
+	}
+#else
 	if (big_endian) {
 		data = BSWAP32(data);
 	}
+#endif
 
 	return data;
 }
@@ -335,9 +347,15 @@ uint64_t FileAccess::get_64() const {
 	uint64_t data = 0;
 	get_buffer(reinterpret_cast<uint8_t *>(&data), sizeof(uint64_t));
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		data = BSWAP64(data);
+	}
+#else
 	if (big_endian) {
 		data = BSWAP64(data);
 	}
+#endif
 
 	return data;
 }
@@ -574,25 +592,43 @@ bool FileAccess::store_8(uint8_t p_dest) {
 }
 
 bool FileAccess::store_16(uint16_t p_dest) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_dest = BSWAP16(p_dest);
+	}
+#else
 	if (big_endian) {
 		p_dest = BSWAP16(p_dest);
 	}
+#endif
 
 	return store_buffer(reinterpret_cast<uint8_t *>(&p_dest), sizeof(uint16_t));
 }
 
 bool FileAccess::store_32(uint32_t p_dest) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_dest = BSWAP32(p_dest);
+	}
+#else
 	if (big_endian) {
 		p_dest = BSWAP32(p_dest);
 	}
+#endif
 
 	return store_buffer(reinterpret_cast<uint8_t *>(&p_dest), sizeof(uint32_t));
 }
 
 bool FileAccess::store_64(uint64_t p_dest) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_dest = BSWAP64(p_dest);
+	}
+#else
 	if (big_endian) {
 		p_dest = BSWAP64(p_dest);
 	}
+#endif
 
 	return store_buffer(reinterpret_cast<uint8_t *>(&p_dest), sizeof(uint64_t));
 }

core/io/file_access.h

@@ -86,7 +86,11 @@ public:
 	typedef void (*FileCloseFailNotify)(const String &);
 
 	typedef Ref<FileAccess> (*CreateFunc)();
+#ifdef BIG_ENDIAN_ENABLED
+	bool big_endian = true;
+#else
 	bool big_endian = false;
+#endif
 	bool real_is_double = false;
 
 	virtual BitField<UnixPermissionFlags> _get_unix_permissions(const String &p_file) = 0;

core/io/resource_format_binary.cpp

@@ -1342,13 +1342,10 @@ Error ResourceFormatLoaderBinary::rename_dependencies(const String &p_path, cons
 	bool use_real64 = f->get_32();
 
 	f->set_big_endian(big_endian != 0); //read big endian if saved as big endian
-#ifdef BIG_ENDIAN_ENABLED
+
-	fw->store_32(!big_endian);
-#else
 	fw->store_32(big_endian);
-#endif
-	fw->set_big_endian(big_endian != 0);
 	fw->store_32(use_real64); //use real64
+	fw->set_big_endian(big_endian != 0);
 
 	uint32_t ver_major = f->get_32();
 	uint32_t ver_minor = f->get_32();
@@ -2168,12 +2165,12 @@ Error ResourceFormatSaverBinaryInstance::save(const String &p_path, const Ref<Re
 
 	if (big_endian) {
 		f->store_32(1);
-		f->set_big_endian(true);
 	} else {
 		f->store_32(0);
 	}
-
 	f->store_32(0); //64 bits file, false for now
+	f->set_big_endian(big_endian);
+
 	f->store_32(GODOT_VERSION_MAJOR);
 	f->store_32(GODOT_VERSION_MINOR);
 	f->store_32(FORMAT_VERSION);
@@ -2412,13 +2409,10 @@ Error ResourceFormatSaverBinaryInstance::set_uid(const String &p_path, ResourceU
 	big_endian = f->get_32();
 	bool use_real64 = f->get_32();
 	f->set_big_endian(big_endian != 0); //read big endian if saved as big endian
-#ifdef BIG_ENDIAN_ENABLED
+
-	fw->store_32(!big_endian);
-#else
 	fw->store_32(big_endian);
-#endif
-	fw->set_big_endian(big_endian != 0);
 	fw->store_32(use_real64); //use real64
+	fw->set_big_endian(big_endian != 0);
 
 	uint32_t ver_major = f->get_32();
 	uint32_t ver_minor = f->get_32();

core/io/stream_peer.cpp

@@ -125,54 +125,90 @@ void StreamPeer::put_8(int8_t p_val) {
 }
 
 void StreamPeer::put_u16(uint16_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP16(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP16(p_val);
 	}
+#endif
 	uint8_t buf[2];
 	encode_uint16(p_val, buf);
 	put_data(buf, 2);
 }
 
 void StreamPeer::put_16(int16_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP16(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP16(p_val);
 	}
+#endif
 	uint8_t buf[2];
 	encode_uint16(p_val, buf);
 	put_data(buf, 2);
 }
 
 void StreamPeer::put_u32(uint32_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP32(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP32(p_val);
 	}
+#endif
 	uint8_t buf[4];
 	encode_uint32(p_val, buf);
 	put_data(buf, 4);
 }
 
 void StreamPeer::put_32(int32_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP32(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP32(p_val);
 	}
+#endif
 	uint8_t buf[4];
 	encode_uint32(p_val, buf);
 	put_data(buf, 4);
 }
 
 void StreamPeer::put_u64(uint64_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP64(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP64(p_val);
 	}
+#endif
 	uint8_t buf[8];
 	encode_uint64(p_val, buf);
 	put_data(buf, 8);
 }
 
 void StreamPeer::put_64(int64_t p_val) {
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		p_val = BSWAP64(p_val);
+	}
+#else
 	if (big_endian) {
 		p_val = BSWAP64(p_val);
 	}
+#endif
 	uint8_t buf[8];
 	encode_uint64(p_val, buf);
 	put_data(buf, 8);
@@ -183,9 +219,15 @@ void StreamPeer::put_half(float p_val) {
 
 	encode_half(p_val, buf);
 	uint16_t *p16 = (uint16_t *)buf;
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		*p16 = BSWAP16(*p16);
+	}
+#else
 	if (big_endian) {
 		*p16 = BSWAP16(*p16);
 	}
+#endif
 
 	put_data(buf, 2);
 }
@@ -194,10 +236,17 @@ void StreamPeer::put_float(float p_val) {
 	uint8_t buf[4];
 
 	encode_float(p_val, buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		uint32_t *p32 = (uint32_t *)buf;
+		*p32 = BSWAP32(*p32);
+	}
+#else
 	if (big_endian) {
 		uint32_t *p32 = (uint32_t *)buf;
 		*p32 = BSWAP32(*p32);
 	}
+#endif
 
 	put_data(buf, 4);
 }
@@ -206,10 +255,17 @@ void StreamPeer::put_double(double p_val) {
 	uint8_t buf[8];
 
 	encode_double(p_val, buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		uint64_t *p64 = (uint64_t *)buf;
+		*p64 = BSWAP64(*p64);
+	}
+#else
 	if (big_endian) {
 		uint64_t *p64 = (uint64_t *)buf;
 		*p64 = BSWAP64(*p64);
 	}
+#endif
 
 	put_data(buf, 8);
 }
@@ -253,9 +309,15 @@ uint16_t StreamPeer::get_u16() {
 	get_data(buf, 2);
 
 	uint16_t r = decode_uint16(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP16(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP16(r);
 	}
+#endif
 
 	return r;
 }
@@ -265,9 +327,15 @@ int16_t StreamPeer::get_16() {
 	get_data(buf, 2);
 
 	uint16_t r = decode_uint16(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP16(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP16(r);
 	}
+#endif
 
 	return int16_t(r);
 }
@@ -277,9 +345,15 @@ uint32_t StreamPeer::get_u32() {
 	get_data(buf, 4);
 
 	uint32_t r = decode_uint32(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP32(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP32(r);
 	}
+#endif
 
 	return r;
 }
@@ -289,9 +363,15 @@ int32_t StreamPeer::get_32() {
 	get_data(buf, 4);
 
 	uint32_t r = decode_uint32(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP32(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP32(r);
 	}
+#endif
 
 	return int32_t(r);
 }
@@ -301,9 +381,15 @@ uint64_t StreamPeer::get_u64() {
 	get_data(buf, 8);
 
 	uint64_t r = decode_uint64(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP64(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP64(r);
 	}
+#endif
 
 	return r;
 }
@@ -313,9 +399,15 @@ int64_t StreamPeer::get_64() {
 	get_data(buf, 8);
 
 	uint64_t r = decode_uint64(buf);
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		r = BSWAP64(r);
+	}
+#else
 	if (big_endian) {
 		r = BSWAP64(r);
 	}
+#endif
 
 	return int64_t(r);
 }
@@ -324,10 +416,17 @@ float StreamPeer::get_half() {
 	uint8_t buf[2];
 	get_data(buf, 2);
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		uint16_t *p16 = (uint16_t *)buf;
+		*p16 = BSWAP16(*p16);
+	}
+#else
 	if (big_endian) {
 		uint16_t *p16 = (uint16_t *)buf;
 		*p16 = BSWAP16(*p16);
 	}
+#endif
 
 	return decode_half(buf);
 }
@@ -336,10 +435,17 @@ float StreamPeer::get_float() {
 	uint8_t buf[4];
 	get_data(buf, 4);
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		uint32_t *p32 = (uint32_t *)buf;
+		*p32 = BSWAP32(*p32);
+	}
+#else
 	if (big_endian) {
 		uint32_t *p32 = (uint32_t *)buf;
 		*p32 = BSWAP32(*p32);
 	}
+#endif
 
 	return decode_float(buf);
 }
@@ -348,10 +454,17 @@ double StreamPeer::get_double() {
 	uint8_t buf[8];
 	get_data(buf, 8);
 
+#ifdef BIG_ENDIAN_ENABLED
+	if (!big_endian) {
+		uint64_t *p64 = (uint64_t *)buf;
+		*p64 = BSWAP64(*p64);
+	}
+#else
 	if (big_endian) {
 		uint64_t *p64 = (uint64_t *)buf;
 		*p64 = BSWAP64(*p64);
 	}
+#endif
 
 	return decode_double(buf);
 }

core/io/stream_peer.h

@@ -49,7 +49,11 @@ protected:
 	Array _get_data(int p_bytes);
 	Array _get_partial_data(int p_bytes);
 
+#ifdef BIG_ENDIAN_ENABLED
+	bool big_endian = true;
+#else
 	bool big_endian = false;
+#endif
 
 public:
 	virtual Error put_data(const uint8_t *p_data, int p_bytes) = 0; ///< put a whole chunk of data, blocking until it sent

doc/classes/FileAccess.xml

@@ -569,8 +569,7 @@
 	<members>
 		<member name="big_endian" type="bool" setter="set_big_endian" getter="is_big_endian">
 			If [code]true[/code], the file is read with big-endian [url=https://en.wikipedia.org/wiki/Endianness]endianness[/url]. If [code]false[/code], the file is read with little-endian endianness. If in doubt, leave this to [code]false[/code] as most files are written with little-endian endianness.
-			[b]Note:[/b] [member big_endian] is only about the file format, not the CPU type. The CPU endianness doesn't affect the default endianness for files written.
+			[b]Note:[/b] This is always reset to system endianness, which is little-endian on all supported platforms, whenever you open the file. Therefore, you must set [member big_endian] [i]after[/i] opening the file, not before.
-			[b]Note:[/b] This is always reset to [code]false[/code] whenever you open the file. Therefore, you must set [member big_endian] [i]after[/i] opening the file, not before.
 		</member>
 	</members>
 	<constants>

doc/classes/PackedByteArray.xml

@@ -346,13 +346,13 @@
 		<method name="get_string_from_utf16" qualifiers="const">
 			<return type="String" />
 			<description>
-				Converts UTF-16 encoded array to [String]. If the BOM is missing, system endianness is assumed. Returns empty string if source array is not valid UTF-16 string. This is the inverse of [method String.to_utf16_buffer].
+				Converts UTF-16 encoded array to [String]. If the BOM is missing, little-endianness is assumed. Returns empty string if source array is not valid UTF-16 string. This is the inverse of [method String.to_utf16_buffer].
 			</description>
 		</method>
 		<method name="get_string_from_utf32" qualifiers="const">
 			<return type="String" />
 			<description>
-				Converts UTF-32 encoded array to [String]. System endianness is assumed. Returns empty string if source array is not valid UTF-32 string. This is the inverse of [method String.to_utf32_buffer].
+				Converts UTF-32 encoded array to [String]. Returns empty string if source array is not valid UTF-32 string. This is the inverse of [method String.to_utf32_buffer].
 			</description>
 		</method>
 		<method name="get_string_from_wchar" qualifiers="const">