serialize.h: use machine native byte swapping if available, fall-back to previous generic method if not (supported for GCC using endian.h, detection done in cmake) write/readARGB8() - just write 32-bit color in one op, instead of 4 1-byte ops cleanup: removed unneeded buffer init for some serialize-out functions use a #define for the fixed point factor in read/writeF1000()

nodemetadata.cpp, nodetimer.cpp
	optimzation: simpler deserialize node position method

staticobject.cpp:
	cleanup: use util/serialize.h inlines instead of its own de/serialization

serialize.cpp:
	minor optimization/cleanup: avoid generation of unneeded string temporary

CMakeLists.txt, cmake_config.h.in: detection of endian.h

config.h: added HAVE_ENDIAN_H

Commits due to feedback squashed

Signed-off-by: Craig Robbins <kde.psych@gmail.com>

8 files changed, 115 insertions, 85 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index b1fd26247..ec6c7fbac 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,6 +2,7 @@ project(minetest)
 cmake_minimum_required( VERSION 2.6 )
 
 INCLUDE(CheckCSourceRuns)
+INCLUDE(CheckIncludeFiles)
 
 # Set some random things default to not being visible in the GUI
 mark_as_advanced(EXECUTABLE_OUTPUT_PATH LIBRARY_OUTPUT_PATH)
@@ -313,6 +314,8 @@ if(ENABLE_REDIS)
 	endif(REDIS_LIBRARY AND REDIS_INCLUDE_DIR)
 endif(ENABLE_REDIS)
 
+CHECK_INCLUDE_FILES(endian.h HAVE_ENDIAN_H)
+
 configure_file(
 	"${PROJECT_SOURCE_DIR}/cmake_config.h.in"
 	"${PROJECT_BINARY_DIR}/cmake_config.h"
diff --git a/src/cmake_config.h.in b/src/cmake_config.h.in
index 64a4c002b..e111a650d 100644
--- a/src/cmake_config.h.in
+++ b/src/cmake_config.h.in
@@ -20,6 +20,7 @@
 #define CMAKE_VERSION_PATCH @VERSION_PATCH@
 #define CMAKE_VERSION_PATCH_ORIG @VERSION_PATCH_ORIG@
 #define CMAKE_VERSION_EXTRA_STRING "@VERSION_EXTRA@"
+#define CMAKE_HAVE_ENDIAN_H @HAVE_ENDIAN_H@
 
 #ifdef NDEBUG
 	#define CMAKE_BUILD_TYPE "Release"
diff --git a/src/config.h b/src/config.h
index f1aef03aa..b07aa5d22 100644
--- a/src/config.h
+++ b/src/config.h
@@ -36,6 +36,8 @@
 	#define USE_REDIS 0
 #endif
 
+#define HAVE_ENDIAN_H 0
+
 #ifdef USE_CMAKE_CONFIG_H
 	#include "cmake_config.h"
 	#undef PROJECT_NAME
@@ -72,6 +74,8 @@
 	#define PRODUCT_VERSION_STRING CMAKE_PRODUCT_VERSION_STRING
 	#undef VERSION_EXTRA_STRING
 	#define VERSION_EXTRA_STRING CMAKE_VERSION_EXTRA_STRING
+	#undef HAVE_ENDIAN_H
+	#define HAVE_ENDIAN_H CMAKE_HAVE_ENDIAN_H
 #endif
 
 #ifdef __ANDROID__
diff --git a/src/nodemetadata.cpp b/src/nodemetadata.cpp
index 4cdd61767..0631d974a 100644
--- a/src/nodemetadata.cpp
+++ b/src/nodemetadata.cpp
@@ -130,12 +130,12 @@ void NodeMetadataList::deSerialize(std::istream &is, IGameDef *gamedef)
 	{
 		u16 p16 = readU16(is);
 
-		v3s16 p(0,0,0);
-		p.Z += p16 / MAP_BLOCKSIZE / MAP_BLOCKSIZE;
-		p16 -= p.Z * MAP_BLOCKSIZE * MAP_BLOCKSIZE;
-		p.Y += p16 / MAP_BLOCKSIZE;
-		p16 -= p.Y * MAP_BLOCKSIZE;
-		p.X += p16;
+		v3s16 p;
+		p.Z = p16 / MAP_BLOCKSIZE / MAP_BLOCKSIZE;
+		p16 &= MAP_BLOCKSIZE * MAP_BLOCKSIZE - 1;
+		p.Y = p16 / MAP_BLOCKSIZE;
+		p16 &= MAP_BLOCKSIZE - 1;
+		p.X = p16;
 
 		if(m_data.find(p) != m_data.end())
 		{
diff --git a/src/nodetimer.cpp b/src/nodetimer.cpp
index 5fc652bb7..d4971c873 100644
--- a/src/nodetimer.cpp
+++ b/src/nodetimer.cpp
@@ -96,12 +96,12 @@ void NodeTimerList::deSerialize(std::istream &is, u8 map_format_version)
 	{
 		u16 p16 = readU16(is);
 
-		v3s16 p(0,0,0);
-		p.Z += p16 / MAP_BLOCKSIZE / MAP_BLOCKSIZE;
-		p16 -= p.Z * MAP_BLOCKSIZE * MAP_BLOCKSIZE;
-		p.Y += p16 / MAP_BLOCKSIZE;
-		p16 -= p.Y * MAP_BLOCKSIZE;
-		p.X += p16;
+		v3s16 p;
+		p.Z = p16 / MAP_BLOCKSIZE / MAP_BLOCKSIZE;
+		p16 &= MAP_BLOCKSIZE * MAP_BLOCKSIZE - 1;
+		p.Y = p16 / MAP_BLOCKSIZE;
+		p16 &= MAP_BLOCKSIZE - 1;
+		p.X = p16;
 
 		NodeTimer t;
 		t.deSerialize(is);
diff --git a/src/staticobject.cpp b/src/staticobject.cpp
index 973257fcf..16d98605b 100644
--- a/src/staticobject.cpp
+++ b/src/staticobject.cpp
@@ -22,42 +22,31 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 void StaticObject::serialize(std::ostream &os)
 {
-	char buf[12];
 	// type
-	buf[0] = type;
-	os.write(buf, 1);
+	writeU8(os, type);
 	// pos
-	writeV3S32((u8*)buf, v3s32(pos.X*1000,pos.Y*1000,pos.Z*1000));
-	os.write(buf, 12);
+	writeV3F1000(os, pos);
 	// data
 	os<<serializeString(data);
 }
 void StaticObject::deSerialize(std::istream &is, u8 version)
 {
-	char buf[12];
 	// type
-	is.read(buf, 1);
-	type = buf[0];
+	type = readU8(is);
 	// pos
-	is.read(buf, 12);
-	v3s32 intp = readV3S32((u8*)buf);
-	pos.X = (f32)intp.X/1000;
-	pos.Y = (f32)intp.Y/1000;
-	pos.Z = (f32)intp.Z/1000;
+	pos = readV3F1000(is);
 	// data
 	data = deSerializeString(is);
 }
 
 void StaticObjectList::serialize(std::ostream &os)
 {
-	char buf[12];
 	// version
-	buf[0] = 0;
-	os.write(buf, 1);
+	u8 version = 0;
+	writeU8(os, version);
 	// count
 	u16 count = m_stored.size() + m_active.size();
-	writeU16((u8*)buf, count);
-	os.write(buf, 2);
+	writeU16(os, count);
 	for(std::list<StaticObject>::iterator
 			i = m_stored.begin();
 			i != m_stored.end(); ++i)
@@ -75,13 +64,10 @@ void StaticObjectList::serialize(std::ostream &os)
 }
 void StaticObjectList::deSerialize(std::istream &is)
 {
-	char buf[12];
 	// version
-	is.read(buf, 1);
-	u8 version = buf[0];
+	u8 version = readU8(is);
 	// count
-	is.read(buf, 2);
-	u16 count = readU16((u8*)buf);
+	u16 count = readU16(is);
 	for(u16 i=0; i<count; i++)
 	{
 		StaticObject s_obj;
diff --git a/src/util/serialize.cpp b/src/util/serialize.cpp
index 8779ee634..8a108a0ff 100644
--- a/src/util/serialize.cpp
+++ b/src/util/serialize.cpp
@@ -68,11 +68,11 @@ std::string deSerializeString(std::istream &is)
 	if(is.gcount() != 2)
 		throw SerializationError("deSerializeString: size not read");
 	u16 s_size = readU16((u8*)buf);
+	std::string s;
 	if(s_size == 0)
-		return "";
+		return s;
 	Buffer<char> buf2(s_size);
 	is.read(&buf2[0], s_size);
-	std::string s;
 	s.reserve(s_size);
 	s.append(&buf2[0], s_size);
 	return s;
@@ -86,9 +86,9 @@ std::wstring deSerializeWideString(std::istream &is)
 	if(is.gcount() != 2)
 		throw SerializationError("deSerializeString: size not read");
 	u16 s_size = readU16((u8*)buf);
-	if(s_size == 0)
-		return L"";
 	std::wstring s;
+	if(s_size == 0)
+		return s;
 	s.reserve(s_size);
 	for(u32 i=0; i<s_size; i++)
 	{
@@ -118,11 +118,11 @@ std::string deSerializeLongString(std::istream &is)
 	if(is.gcount() != 4)
 		throw SerializationError("deSerializeLongString: size not read");
 	u32 s_size = readU32((u8*)buf);
+	std::string s;
 	if(s_size == 0)
-		return "";
+		return s;
 	Buffer<char> buf2(s_size);
 	is.read(&buf2[0], s_size);
-	std::string s;
 	s.reserve(s_size);
 	s.append(&buf2[0], s_size);
 	return s;
diff --git a/src/util/serialize.h b/src/util/serialize.h
index 3f9925287..79907799f 100644
--- a/src/util/serialize.h
+++ b/src/util/serialize.h
@@ -21,9 +21,63 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #define UTIL_SERIALIZE_HEADER
 
 #include "../irrlichttypes_bloated.h"
+#include "config.h"
+#if HAVE_ENDIAN_H
+#include <endian.h>
+#include <string.h> // for memcpy
+#endif
 #include <iostream>
 #include <string>
 
+#define FIXEDPOINT_FACTOR 1000.0f
+#define FIXEDPOINT_INVFACTOR (1.0f/FIXEDPOINT_FACTOR)
+
+#if HAVE_ENDIAN_H
+// use machine native byte swapping routines
+// Note: memcpy below is optimized out by modern compilers
+
+inline void writeU64(u8* data, u64 i)
+{
+	u64 val = htobe64(i);
+	memcpy(data, &val, 8);
+}
+
+inline void writeU32(u8* data, u32 i)
+{
+	u32 val = htobe32(i);
+	memcpy(data, &val, 4);
+}
+
+inline void writeU16(u8* data, u16 i)
+{
+	u16 val = htobe16(i);
+	memcpy(data, &val, 2);
+}
+
+inline u64 readU64(const u8* data)
+{
+	u64 val;
+	memcpy(&val, data, 8);
+	return be64toh(val);
+}
+
+inline u32 readU32(const u8* data)
+{
+	u32 val;
+	memcpy(&val, data, 4);
+	return be32toh(val);
+}
+
+inline u16 readU16(const u8* data)
+{
+	u16 val;
+	memcpy(&val, data, 2);
+	return be16toh(val);
+}
+
+#else
+// generic byte-swapping implementation
+
 inline void writeU64(u8 *data, u64 i)
 {
 	data[0] = ((i>>56)&0xff);
@@ -50,11 +104,6 @@ inline void writeU16(u8 *data, u16 i)
 	data[1] = ((i>> 0)&0xff);
 }
 
-inline void writeU8(u8 *data, u8 i)
-{
-	data[0] = ((i>> 0)&0xff);
-}
-
 inline u64 readU64(const u8 *data)
 {
 	return ((u64)data[0]<<56) | ((u64)data[1]<<48)
@@ -73,6 +122,13 @@ inline u16 readU16(const u8 *data)
 	return (data[0]<<8) | (data[1]<<0);
 }
 
+#endif
+
+inline void writeU8(u8 *data, u8 i)
+{
+	data[0] = ((i>> 0)&0xff);
+}
+
 inline u8 readU8(const u8 *data)
 {
 	return (data[0]<<0);
@@ -100,10 +156,10 @@ inline s8 readS8(const u8 *data){
 }
 
 inline void writeF1000(u8 *data, f32 i){
-	writeS32(data, i*1000);
+	writeS32(data, i*FIXEDPOINT_FACTOR);
 }
 inline f32 readF1000(const u8 *data){
-	return (f32)readS32(data)/1000.;
+	return (f32)readS32(data)*FIXEDPOINT_INVFACTOR;
 }
 
 inline void writeV3S32(u8 *data, v3s32 p)
@@ -195,20 +251,12 @@ inline v3s16 readV3S16(const u8 *data)
 
 inline void writeARGB8(u8 *data, video::SColor p)
 {
-	writeU8(&data[0], p.getAlpha());
-	writeU8(&data[1], p.getRed());
-	writeU8(&data[2], p.getGreen());
-	writeU8(&data[3], p.getBlue());
+	writeU32(data, p.color);
 }
 
 inline video::SColor readARGB8(const u8 *data)
 {
-	video::SColor p(
-		readU8(&data[0]),
-		readU8(&data[1]),
-		readU8(&data[2]),
-		readU8(&data[3])
-	);
+	video::SColor p(readU32(data));
 	return p;
 }
 
@@ -218,7 +266,7 @@ inline video::SColor readARGB8(const u8 *data)
 
 inline void writeU8(std::ostream &os, u8 p)
 {
-	char buf[1] = {0};
+	char buf[1];
 	writeU8((u8*)buf, p);
 	os.write(buf, 1);
 }
@@ -231,7 +279,7 @@ inline u8 readU8(std::istream &is)
 
 inline void writeU16(std::ostream &os, u16 p)
 {
-	char buf[2] = {0};
+	char buf[2];
 	writeU16((u8*)buf, p);
 	os.write(buf, 2);
 }
@@ -244,7 +292,7 @@ inline u16 readU16(std::istream &is)
 
 inline void writeU32(std::ostream &os, u32 p)
 {
-	char buf[4] = {0};
+	char buf[4];
 	writeU32((u8*)buf, p);
 	os.write(buf, 4);
 }
@@ -257,46 +305,34 @@ inline u32 readU32(std::istream &is)
 
 inline void writeS32(std::ostream &os, s32 p)
 {
-	char buf[4] = {0};
-	writeS32((u8*)buf, p);
-	os.write(buf, 4);
+	writeU32(os, (u32) p);
 }
 inline s32 readS32(std::istream &is)
 {
-	char buf[4] = {0};
-	is.read(buf, 4);
-	return readS32((u8*)buf);
+	return (s32)readU32(is);
 }
 
 inline void writeS16(std::ostream &os, s16 p)
 {
-	char buf[2] = {0};
-	writeS16((u8*)buf, p);
-	os.write(buf, 2);
+	writeU16(os, (u16) p);
 }
 inline s16 readS16(std::istream &is)
 {
-	char buf[2] = {0};
-	is.read(buf, 2);
-	return readS16((u8*)buf);
+	return (s16)readU16(is);
 }
 
 inline void writeS8(std::ostream &os, s8 p)
 {
-	char buf[1] = {0};
-	writeS8((u8*)buf, p);
-	os.write(buf, 1);
+	writeU8(os, (u8) p);
 }
 inline s8 readS8(std::istream &is)
 {
-	char buf[1] = {0};
-	is.read(buf, 1);
-	return readS8((u8*)buf);
+	return (s8)readU8(is);
 }
 
 inline void writeF1000(std::ostream &os, f32 p)
 {
-	char buf[4] = {0};
+	char buf[4];
 	writeF1000((u8*)buf, p);
 	os.write(buf, 4);
 }
@@ -322,7 +358,7 @@ inline v3f readV3F1000(std::istream &is)
 
 inline void writeV2F1000(std::ostream &os, v2f p)
 {
-	char buf[8] = {0};
+	char buf[8];
 	writeV2F1000((u8*)buf, p);
 	os.write(buf, 8);
 }
@@ -335,7 +371,7 @@ inline v2f readV2F1000(std::istream &is)
 
 inline void writeV2S16(std::ostream &os, v2s16 p)
 {
-	char buf[4] = {0};
+	char buf[4];
 	writeV2S16((u8*)buf, p);
 	os.write(buf, 4);
 }
@@ -348,7 +384,7 @@ inline v2s16 readV2S16(std::istream &is)
 
 inline void writeV2S32(std::ostream &os, v2s32 p)
 {
-	char buf[8] = {0};
+	char buf[8];
 	writeV2S32((u8*)buf, p);
 	os.write(buf, 8);
 }
@@ -361,7 +397,7 @@ inline v2s32 readV2S32(std::istream &is)
 
 inline void writeV3S16(std::ostream &os, v3s16 p)
 {
-	char buf[6] = {0};
+	char buf[6];
 	writeV3S16((u8*)buf, p);
 	os.write(buf, 6);
 }
@@ -374,7 +410,7 @@ inline v3s16 readV3S16(std::istream &is)
 
 inline void writeARGB8(std::ostream &os, video::SColor p)
 {
-	char buf[4] = {0};
+	char buf[4];
 	writeARGB8((u8*)buf, p);
 	os.write(buf, 4);
 }