From 21a51e87c4d0850c77fb7c5e4decef91ced7adbd Mon Sep 17 00:00:00 2001
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
Date: Sat, 24 Sep 2011 19:25:02 +0300
Subject: [PATCH] Add functions to read/write multibyte values from/to host
 memory

---
 lua/hostmemory.cpp | 102 ++++++++++++++++++++++++++++----
 manual.lyx         | 144 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 236 insertions(+), 10 deletions(-)

diff --git a/lua/hostmemory.cpp b/lua/hostmemory.cpp
index d814ba0b..6827c922 100644
--- a/lua/hostmemory.cpp
+++ b/lua/hostmemory.cpp
@@ -3,24 +3,106 @@
 
 namespace
 {
-	function_ptr_luafun hm_read("hostmemory.read", [](lua_State* LS, const std::string& fname) -> int {
+	template<typename U, typename S>
+	int do_read(lua_State* LS, const std::string& fname)
+	{
 		size_t address = get_numeric_argument<size_t>(LS, 1, fname.c_str());
 		auto& h = get_host_memory();
-		if(address >= h.size()) {
+		if(address + sizeof(U) > h.size()) {
 			lua_pushboolean(LS, 0);
 			return 1;
 		}
-		lua_pushnumber(LS, static_cast<uint8_t>(h[address]));
+		U ret = 0;
+		for(size_t i = 0; i < sizeof(U); i++)
+			ret = 256 * ret + static_cast<uint8_t>(h[address + i]);
+		lua_pushnumber(LS, static_cast<S>(ret));
 		return 1;
+	}
+
+	template<typename U, typename S>
+	int do_write(lua_State* LS, const std::string& fname)
+	{
+		size_t address = get_numeric_argument<size_t>(LS, 1, fname.c_str());
+		U value = static_cast<U>(get_numeric_argument<S>(LS, 2, fname.c_str()));
+		auto& h = get_host_memory();
+		if(address + sizeof(U) > h.size())
+			h.resize(address + sizeof(U));
+		for(size_t i = sizeof(U) - 1; i < sizeof(U); i--) {
+			h[address + i] = value;
+			value >>= 8;
+		}
+		return 0;
+	}
+
+	function_ptr_luafun hm_read("hostmemory.read", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint8_t, uint8_t>(LS, fname);
 	});
 
 	function_ptr_luafun hm_write("hostmemory.write", [](lua_State* LS, const std::string& fname) -> int {
-		size_t address = get_numeric_argument<size_t>(LS, 1, fname.c_str());
-		uint8_t value = get_numeric_argument<uint8_t>(LS, 2, fname.c_str());
-		auto& h = get_host_memory();
-		if(address >= h.size())
-			h.resize(address + 1);
-		h[address] = value;
-		return 0;
+		return do_write<uint8_t, uint8_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readb("hostmemory.readbyte", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint8_t, uint8_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writeb("hostmemory.writebyte", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint8_t, uint8_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readsb("hostmemory.readsbyte", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint8_t, int8_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writesb("hostmemory.writesbyte", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint8_t, int8_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readw("hostmemory.readword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint16_t, uint16_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writew("hostmemory.writeword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint16_t, uint16_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readsw("hostmemory.readsword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint16_t, int16_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writesw("hostmemory.writesword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint16_t, int16_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readd("hostmemory.readdword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint32_t, uint32_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writed("hostmemory.writedword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint32_t, uint32_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readsd("hostmemory.readsdword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint32_t, int32_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writesd("hostmemory.writesdword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint32_t, int32_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readq("hostmemory.readqword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint64_t, uint64_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writeq("hostmemory.writeqword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint64_t, uint64_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_readsq("hostmemory.readsqword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_read<uint64_t, int64_t>(LS, fname);
+	});
+
+	function_ptr_luafun hm_writesq("hostmemory.writesqword", [](lua_State* LS, const std::string& fname) -> int {
+		return do_write<uint64_t, int64_t>(LS, fname);
 	});
 }
diff --git a/manual.lyx b/manual.lyx
index e134cadc..c08a7151 100644
--- a/manual.lyx
+++ b/manual.lyx
@@ -1881,6 +1881,150 @@ Writes hostmemory slot with 0-255.
  Slot numbers out of range cause extension of host memory slot space.
 \end_layout
 
+\begin_layout Subsubsection
+readbyte(number address)
+\end_layout
+
+\begin_layout Standard
+Read unsigned byte (1 element) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writebyte(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write unsigned byte (1 element) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readsbyte(number address)
+\end_layout
+
+\begin_layout Standard
+Read signed byte (1 element) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writesbyte(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write signed byte (1 element) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readword(number address)
+\end_layout
+
+\begin_layout Standard
+Read unsigned word (2 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writeword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write unsigned word (2 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readsword(number address)
+\end_layout
+
+\begin_layout Standard
+Read signed word (2 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writesword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write signed word (2 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readdword(number address)
+\end_layout
+
+\begin_layout Standard
+Read unsigned doubleword (4 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writedword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write unsigned doubleword (4 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readsdword(number address)
+\end_layout
+
+\begin_layout Standard
+Read signed doubleword (4 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writesdword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write signed doubleword (4 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readqword(number address)
+\end_layout
+
+\begin_layout Standard
+Read unsigned quadword (8 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writeqword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write unsigned quadword (4 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
+\begin_layout Subsubsection
+readsqword(number address)
+\end_layout
+
+\begin_layout Standard
+Read signed quadword (8 elements) from given address.
+ Slots out of range return false.
+\end_layout
+
+\begin_layout Subsubsection
+writesqword(number address, number value)
+\end_layout
+
+\begin_layout Standard
+Write signed quadword (8 elements) to given slot.
+ Slot numbers out of range cause extension.
+\end_layout
+
 \begin_layout Subsection
 Table movie
 \end_layout