Merge pull request #21 from lunarmodules/terminal

11 files changed, 1779 insertions, 9 deletions

diff --git a/src/bitflags.c b/src/bitflags.c
new file mode 100644
index 0000000..e397918
--- /dev/null
+++ b/src/bitflags.c
@@ -0,0 +1,270 @@
+/// Bitflags module.
+// The bitflag object makes it easy to manipulate flags in a bitmask.
+//
+// It has metamethods that do the hard work, adding flags sets them, substracting
+// unsets them. Comparing flags checks if all flags in the second set are also set
+// in the first set. The `has` method checks if all flags in the second set are
+// also set in the first set, but behaves slightly different.
+//
+// Indexing allows checking values or setting them by bit index (eg. 0-7 for flags
+// in the first byte).
+//
+// _NOTE_: unavailable flags (eg. Windows flags on a Posix system) should not be
+// omitted, but be assigned a value of 0. This is because the `has` method will
+// return `false` if the flags are checked and the value is 0.
+//
+// See `system.bitflag` (the constructor) for extensive examples on usage.
+// @classmod bitflags
+#include "bitflags.h"
+
+#define BITFLAGS_MT_NAME "LuaSystem.BitFlags"
+
+typedef struct {
+    LSBF_BITFLAG flags;
+} LS_BitFlags;
+
+/// Bit flags.
+// Bitflag objects can be used to easily manipulate and compare bit flags.
+// These are primarily for use with the terminal functions, but can be used
+// in other places as well.
+// @section bitflags
+
+
+// pushes a new LS_BitFlags object with the given value onto the stack
+void lsbf_pushbitflags(lua_State *L, LSBF_BITFLAG value) {
+    LS_BitFlags *obj = (LS_BitFlags *)lua_newuserdata(L, sizeof(LS_BitFlags));
+    if (!obj) luaL_error(L, "Memory allocation failed");
+    luaL_getmetatable(L, BITFLAGS_MT_NAME);
+    lua_setmetatable(L, -2);
+    obj->flags = value;
+}
+
+// gets the LS_BitFlags value at the given index. Returns a Lua error if it is not
+// a LS_BitFlags object.
+LSBF_BITFLAG lsbf_checkbitflags(lua_State *L, int index) {
+    LS_BitFlags *obj = (LS_BitFlags *)luaL_checkudata(L, index, BITFLAGS_MT_NAME);
+    return obj->flags;
+}
+
+// Validates that the given index is a table containing a field 'fieldname'
+// which is a bitflag object and returns its value.
+// If the index is not a table or the field is not a bitflag object, a Lua
+// error is raised. If the bitflag is not present, the default value is returned.
+// The stack remains unchanged.
+LSBF_BITFLAG lsbf_checkbitflagsfield(lua_State *L, int index, const char *fieldname, LSBF_BITFLAG default_value) {
+    luaL_checktype(L, index, LUA_TTABLE);
+    lua_getfield(L, index, fieldname);
+
+    // if null, return default value
+    if (lua_isnil(L, -1)) {
+        lua_pop(L, 1);
+        return default_value;
+    }
+
+    // check to bitflags
+    LS_BitFlags *obj = luaL_testudata(L, -1, BITFLAGS_MT_NAME);
+    if (obj == NULL) {
+        lua_pop(L, 1);
+        return luaL_error(L, "bad argument #%d, field '%s' must be a bitflag object", index, fieldname);
+    }
+    LSBF_BITFLAG value = obj->flags;
+    lua_pop(L, 1);
+    return value;
+}
+
+/***
+Creates a new bitflag object from the given value.
+@function system.bitflag
+@tparam[opt=0] number value the value to create the bitflag object from.
+@treturn bitflag bitflag object with the given values set.
+@usage
+local sys = require 'system'
+local flags = sys.bitflag(2)    -- b0010
+
+-- get state of individual bits
+print(flags[0])                 -- false
+print(flags[1])                 -- true
+
+-- set individual bits
+flags[0] = true                 -- b0011
+print(flags:value())            -- 3
+print(flags)                    -- "bitflags: 3"
+
+-- adding flags (bitwise OR)
+local flags1 = sys.bitflag(1)   -- b0001
+local flags2 = sys.bitflag(2)   -- b0010
+local flags3 = flags1 + flags2  -- b0011
+
+-- substracting flags (bitwise AND NOT)
+print(flags3:value())           -- 3
+flag3 = flag3 - flag3           -- b0000
+print(flags3:value())           -- 0
+
+-- comparing flags
+local flags4 = sys.bitflag(7)   -- b0111
+local flags5 = sys.bitflag(255) -- b11111111
+print(flags5 ~= flags4)         -- true, not the same flags
+local flags6 = sys.bitflag(7)   -- b0111
+print(flags6 == flags4)         -- true, same flags
+
+-- comparison of subsets
+local flags7 = sys.bitflag(0)    -- b0000
+local flags8 = sys.bitflag(3)    -- b0011
+local flags9 = sys.bitflag(7)    -- b0111
+print(flags9:has_all_of(flags8)) -- true, flags8 bits are all set in flags9
+print(flags8:has_any_of(flags9)) -- true, some of flags9 bits are set in flags8
+print(flags8:has_all_of(flags7)) -- false, flags7 (== 0) is not set in flags8
+*/
+static int lsbf_new(lua_State *L) {
+    LSBF_BITFLAG flags = 0;
+    if (lua_gettop(L) > 0) {
+        flags = luaL_checkinteger(L, 1);
+    }
+    lsbf_pushbitflags(L, flags);
+    return 1;
+}
+
+/***
+Retrieves the numeric value of the bitflag object.
+@function bitflag:value
+@treturn number the numeric value of the bitflags.
+@usage
+local sys = require 'system'
+local flags = sys.bitflag()     -- b0000
+flags[0] = true                 -- b0001
+flags[2] = true                 -- b0101
+print(flags:value())            -- 5
+*/
+static int lsbf_value(lua_State *L) {
+    lua_pushinteger(L, lsbf_checkbitflags(L, 1));
+    return 1;
+}
+
+static int lsbf_tostring(lua_State *L) {
+    lua_pushfstring(L, "bitflags: %d", lsbf_checkbitflags(L, 1));
+    return 1;
+}
+
+static int lsbf_add(lua_State *L) {
+    lsbf_pushbitflags(L, lsbf_checkbitflags(L, 1) | lsbf_checkbitflags(L, 2));
+    return 1;
+}
+
+static int lsbf_sub(lua_State *L) {
+    lsbf_pushbitflags(L, lsbf_checkbitflags(L, 1) & ~lsbf_checkbitflags(L, 2));
+    return 1;
+}
+
+static int lsbf_eq(lua_State *L) {
+    lua_pushboolean(L, lsbf_checkbitflags(L, 1) == lsbf_checkbitflags(L, 2));
+    return 1;
+}
+
+/***
+Checks if all the flags in the given subset are set.
+If the flags to check has a value `0`, it will always return `false`. So if there are flags that are
+unsupported on a platform, they can be set to 0 and the `has_all_of` function will
+return `false` if the flags are checked.
+@function bitflag:has_all_of
+@tparam bitflag subset the flags to check for.
+@treturn boolean true if all the flags are set, false otherwise.
+@usage
+local sys = require 'system'
+local flags = sys.bitflag(12)     -- b1100
+local myflags = sys.bitflag(15)   -- b1111
+print(flags:has_all_of(myflags))  -- false, not all bits in myflags are set in flags
+print(myflags:has_all_of(flags))  -- true, all bits in flags are set in myflags
+*/
+static int lsbf_has_all_of(lua_State *L) {
+    LSBF_BITFLAG a = lsbf_checkbitflags(L, 1);
+    LSBF_BITFLAG b = lsbf_checkbitflags(L, 2);
+    // Check if all bits in b are also set in a, and b is not 0
+    lua_pushboolean(L, (a & b) == b && b != 0);
+    return 1;
+}
+
+/***
+Checks if any of the flags in the given subset are set.
+If the flags to check has a value `0`, it will always return `false`. So if there are flags that are
+unsupported on a platform, they can be set to 0 and the `has_any_of` function will
+return `false` if the flags are checked.
+@function bitflag:has_any_of
+@tparam bitflag subset the flags to check for.
+@treturn boolean true if any of the flags are set, false otherwise.
+@usage
+local sys = require 'system'
+local flags = sys.bitflag(12)     -- b1100
+local myflags = sys.bitflag(7)    -- b0111
+print(flags:has_any_of(myflags))  -- true, some bits in myflags are set in flags
+print(myflags:has_any_of(flags))  -- true, some bits in flags are set in myflags
+*/
+static int lsbf_has_any_of(lua_State *L) {
+    LSBF_BITFLAG a = lsbf_checkbitflags(L, 1);
+    LSBF_BITFLAG b = lsbf_checkbitflags(L, 2);
+    // Check if any bits in b are set in a
+    lua_pushboolean(L, (a & b) != 0);
+    return 1;
+}
+
+static int lsbf_index(lua_State *L) {
+    if (!lua_isnumber(L, 2)) {
+        // the parameter isn't a number, just lookup the key in the metatable
+        lua_getmetatable(L, 1);
+        lua_pushvalue(L, 2);
+        lua_gettable(L, -2);
+        return 1;
+    }
+
+    int index = luaL_checkinteger(L, 2);
+    if (index < 0 || index >= sizeof(LSBF_BITFLAG) * 8) {
+        return luaL_error(L, "index out of range");
+    }
+    lua_pushboolean(L, (lsbf_checkbitflags(L, 1) & (1 << index)) != 0);
+    return 1;
+}
+
+static int lsbf_newindex(lua_State *L) {
+    LS_BitFlags *obj = (LS_BitFlags *)luaL_checkudata(L, 1, BITFLAGS_MT_NAME);
+
+    if (!lua_isnumber(L, 2)) {
+        return luaL_error(L, "index must be a number");
+    }
+    int index = luaL_checkinteger(L, 2);
+    if (index < 0 || index >= sizeof(LSBF_BITFLAG) * 8) {
+        return luaL_error(L, "index out of range");
+    }
+
+    luaL_checkany(L, 3);
+    if (lua_toboolean(L, 3)) {
+        obj->flags |= (1 << index);
+    } else {
+        obj->flags &= ~(1 << index);
+    }
+    return 0;
+}
+
+static const struct luaL_Reg lsbf_funcs[] = {
+    {"bitflag", lsbf_new},
+    {NULL, NULL}
+};
+
+static const struct luaL_Reg lsbf_methods[] = {
+    {"value", lsbf_value},
+    {"has_all_of", lsbf_has_all_of},
+    {"has_any_of", lsbf_has_any_of},
+    {"__tostring", lsbf_tostring},
+    {"__add", lsbf_add},
+    {"__sub", lsbf_sub},
+    {"__eq", lsbf_eq},
+    {"__index", lsbf_index},
+    {"__newindex", lsbf_newindex},
+    {NULL, NULL}
+};
+
+void bitflags_open(lua_State *L) {
+    luaL_newmetatable(L, BITFLAGS_MT_NAME);
+    luaL_setfuncs(L, lsbf_methods, 0);
+    lua_pop(L, 1);
+
+    luaL_setfuncs(L, lsbf_funcs, 0);
+}
diff --git a/src/bitflags.h b/src/bitflags.h
new file mode 100644
index 0000000..f16b041
--- /dev/null
+++ b/src/bitflags.h
@@ -0,0 +1,30 @@
+#ifndef LSBITFLAGS_H
+#define LSBITFLAGS_H
+
+#include <lua.h>
+#include "compat.h"
+#include <lauxlib.h>
+#include <stdlib.h>
+
+// type used to store the bitflags
+#define LSBF_BITFLAG lua_Integer
+
+// Validates that the given index is a bitflag object and returns its value.
+// If the index is not a bitflag object, a Lua error is raised.
+// The value will be left on the stack.
+LSBF_BITFLAG lsbf_checkbitflags(lua_State *L, int index);
+
+
+// Validates that the given index is a table containing a field 'fieldname'
+// which is a bitflag object and returns its value.
+// If the index is not a table or the field is not a bitflag object, a Lua
+// error is raised. If the bitflag is not present, the default value is returned.
+// The stack remains unchanged.
+LSBF_BITFLAG lsbf_checkbitflagsfield(lua_State *L, int index, const char *fieldname, LSBF_BITFLAG default_value);
+
+
+// Pushes a new bitflag object with the given value onto the stack.
+// Might raise a Lua error if memory allocation fails.
+void lsbf_pushbitflags(lua_State *L, LSBF_BITFLAG value);
+
+#endif
diff --git a/src/compat.c b/src/compat.c
index 6f98854..2d2bec9 100644
--- a/src/compat.c
+++ b/src/compat.c
@@ -14,4 +14,20 @@ void luaL_setfuncs(lua_State *L, const luaL_Reg *l, int nup) {
     }
     lua_pop(L, nup);  /* remove upvalues */
 }
+
+void *luaL_testudata(lua_State *L, int ud, const char *tname) {
+    void *p = lua_touserdata(L, ud);
+    if (p != NULL) {  /* Check for userdata */
+        if (lua_getmetatable(L, ud)) {  /* Does it have a metatable? */
+            lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* Get metatable we're looking for */
+            if (lua_rawequal(L, -1, -2)) {  /* Compare metatables */
+                lua_pop(L, 2);  /* Remove metatables from stack */
+                return p;
+            }
+            lua_pop(L, 2);  /* Remove metatables from stack */
+        }
+    }
+    return NULL;  /* Return NULL if check fails */
+}
+
 #endif
diff --git a/src/compat.h b/src/compat.h
index 35f9ef2..2033aa3 100644
--- a/src/compat.h
+++ b/src/compat.h
@@ -6,6 +6,7 @@
 
 #if LUA_VERSION_NUM == 501
 void luaL_setfuncs(lua_State *L, const luaL_Reg *l, int nup);
+void *luaL_testudata(lua_State *L, int ud, const char *tname);
 #endif
 
 
@@ -13,6 +14,17 @@ void luaL_setfuncs(lua_State *L, const luaL_Reg *l, int nup);
 #include <sys/types.h>
 #endif
 
+// Windows compatibility; define DWORD and TRUE/FALSE on non-Windows
+#ifndef _WIN32
+#ifndef DWORD
+#define DWORD unsigned long
+#endif
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif
+#endif
+
 #ifdef _MSC_VER
 // MSVC Windows doesn't have ssize_t, so we define it here
 #if SIZE_MAX == UINT_MAX
diff --git a/src/core.c b/src/core.c
index 729023f..d233ecc 100644
--- a/src/core.c
+++ b/src/core.c
@@ -16,6 +16,7 @@ void time_open(lua_State *L);
 void environment_open(lua_State *L);
 void random_open(lua_State *L);
 void term_open(lua_State *L);
+void bitflags_open(lua_State *L);
 
 /*-------------------------------------------------------------------------
  * Initializes all library modules.
@@ -32,6 +33,7 @@ LUAEXPORT int luaopen_system_core(lua_State *L) {
     lua_pushboolean(L, 0);
 #endif
     lua_rawset(L, -3);
+    bitflags_open(L); // must be first, used by others
     time_open(L);
     random_open(L);
     term_open(L);
diff --git a/src/environment.c b/src/environment.c
index 5f1c3da..ab5dd92 100644
--- a/src/environment.c
+++ b/src/environment.c
@@ -1,4 +1,8 @@
-/// @submodule system
+/// @module system
+
+/// Environment.
+// @section environment
+
 #include <lua.h>
 #include <lauxlib.h>
 #include "compat.h"
diff --git a/src/random.c b/src/random.c
index 90fb3f2..e55461a 100644
--- a/src/random.c
+++ b/src/random.c
@@ -1,4 +1,9 @@
-/// @submodule system
+/// @module system
+
+/// Random.
+// @section random
+
+
 #include <lua.h>
 #include <lauxlib.h>
 #include "compat.h"
diff --git a/src/term.c b/src/term.c
index 2adb1e9..d8cc38e 100644
--- a/src/term.c
+++ b/src/term.c
@@ -1,37 +1,1158 @@
-/// @submodule system
+/// @module system
+
+/// Terminal.
+// Unix: see https://blog.nelhage.com/2009/12/a-brief-introduction-to-termios-termios3-and-stty/
+//
+// Windows: see https://learn.microsoft.com/en-us/windows/console/console-reference
+// @section terminal
+
 #include <lua.h>
 #include <lauxlib.h>
 #include <lualib.h>
 #include "compat.h"
+#include "bitflags.h"
 
 #ifndef _MSC_VER
 # include <unistd.h>
 #endif
 
+#ifdef _WIN32
+# include <windows.h>
+# include <locale.h>
+#else
+# include <termios.h>
+# include <string.h>
+# include <errno.h>
+# include <fcntl.h>
+# include <sys/ioctl.h>
+# include <unistd.h>
+# include <wchar.h>
+# include <locale.h>
+#endif
+
+
+// Windows does not have a wcwidth function, so we use compatibilty code from
+// http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c by Markus Kuhn
+#include "wcwidth.h"
+
+
+#ifdef _WIN32
+// after an error is returned, GetLastError() result can be passed to this function to get a string
+// representation of the error on the stack.
+// result will be nil+error on the stack, always 2 results.
+static void termFormatError(lua_State *L, DWORD errorCode, const char* prefix) {
+//static void FormatErrorAndReturn(lua_State *L, DWORD errorCode, const char* prefix) {
+    LPSTR messageBuffer = NULL;
+    FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+                   NULL, errorCode, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&messageBuffer, 0, NULL);
+
+    lua_pushnil(L);
+    if (messageBuffer) {
+        if (prefix) {
+            lua_pushfstring(L, "%s: %s", prefix, messageBuffer);
+        } else {
+            lua_pushstring(L, messageBuffer);
+        }
+        LocalFree(messageBuffer);
+    } else {
+        lua_pushfstring(L, "%sError code %d", prefix ? prefix : "", errorCode);
+    }
+}
+#else
+static int pusherror(lua_State *L, const char *info)
+{
+        lua_pushnil(L);
+        if (info==NULL)
+                lua_pushstring(L, strerror(errno));
+        else
+                lua_pushfstring(L, "%s: %s", info, strerror(errno));
+        lua_pushinteger(L, errno);
+        return 3;
+}
+#endif
 
 /***
 Checks if a file-handle is a TTY.
 
 @function isatty
-@tparam file file the file-handle to check
+@tparam file file the file-handle to check, one of `io.stdin`, `io.stdout`, `io.stderr`.
 @treturn boolean true if the file is a tty
+@usage
+local system = require('system')
+if system.isatty(io.stdin) then
+    -- enable ANSI coloring etc on Windows, does nothing in Posix.
+    local flags = system.getconsoleflags(io.stdout)
+    system.setconsoleflags(io.stdout, flags + sys.COF_VIRTUAL_TERMINAL_PROCESSING)
+end
 */
-static int lua_isatty(lua_State* L) {
+static int lst_isatty(lua_State* L) {
     FILE **fh = (FILE **) luaL_checkudata(L, 1, LUA_FILEHANDLE);
     lua_pushboolean(L, isatty(fileno(*fh)));
     return 1;
 }
 
 
+/*-------------------------------------------------------------------------
+ * Windows Get/SetConsoleMode functions
+ *-------------------------------------------------------------------------*/
 
-static luaL_Reg func[] = {
-    { "isatty", lua_isatty },
-    { NULL, NULL }
+typedef struct ls_RegConst {
+  const char *name;
+  DWORD value;
+} ls_RegConst;
+
+// Define a macro to check if a constant is defined and set it to 0 if not.
+// This is needed because some flags are not defined on all platforms. So we
+// still export the constants, but they will be all 0, and hence not do anything.
+#ifdef _WIN32
+#define CHECK_WIN_FLAG_OR_ZERO(flag) flag
+#define CHECK_NIX_FLAG_OR_ZERO(flag) 0
+#else
+#define CHECK_WIN_FLAG_OR_ZERO(flag) 0
+#define CHECK_NIX_FLAG_OR_ZERO(flag) flag
+#endif
+
+// Export Windows constants to Lua
+static const struct ls_RegConst win_console_in_flags[] = {
+    // Console Input Flags
+    {"CIF_ECHO_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_ECHO_INPUT)},
+    {"CIF_INSERT_MODE", CHECK_WIN_FLAG_OR_ZERO(ENABLE_INSERT_MODE)},
+    {"CIF_LINE_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_LINE_INPUT)},
+    {"CIF_MOUSE_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_MOUSE_INPUT)},
+    {"CIF_PROCESSED_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_PROCESSED_INPUT)},
+    {"CIF_QUICK_EDIT_MODE", CHECK_WIN_FLAG_OR_ZERO(ENABLE_QUICK_EDIT_MODE)},
+    {"CIF_WINDOW_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_WINDOW_INPUT)},
+    {"CIF_VIRTUAL_TERMINAL_INPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_VIRTUAL_TERMINAL_INPUT)},
+    {"CIF_EXTENDED_FLAGS", CHECK_WIN_FLAG_OR_ZERO(ENABLE_EXTENDED_FLAGS)},
+    {"CIF_AUTO_POSITION", CHECK_WIN_FLAG_OR_ZERO(ENABLE_AUTO_POSITION)},
+    {NULL, 0}
+};
+
+static const struct ls_RegConst win_console_out_flags[] = {
+    // Console Output Flags
+    {"COF_PROCESSED_OUTPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_PROCESSED_OUTPUT)},
+    {"COF_WRAP_AT_EOL_OUTPUT", CHECK_WIN_FLAG_OR_ZERO(ENABLE_WRAP_AT_EOL_OUTPUT)},
+    {"COF_VIRTUAL_TERMINAL_PROCESSING", CHECK_WIN_FLAG_OR_ZERO(ENABLE_VIRTUAL_TERMINAL_PROCESSING)},
+    {"COF_DISABLE_NEWLINE_AUTO_RETURN", CHECK_WIN_FLAG_OR_ZERO(DISABLE_NEWLINE_AUTO_RETURN)},
+    {"COF_ENABLE_LVB_GRID_WORLDWIDE", CHECK_WIN_FLAG_OR_ZERO(ENABLE_LVB_GRID_WORLDWIDE)},
+    {NULL, 0}
+};
+
+
+// Export Unix constants to Lua
+static const struct ls_RegConst nix_tcsetattr_actions[] = {
+    // The optional actions for tcsetattr
+    {"TCSANOW", CHECK_NIX_FLAG_OR_ZERO(TCSANOW)},
+    {"TCSADRAIN", CHECK_NIX_FLAG_OR_ZERO(TCSADRAIN)},
+    {"TCSAFLUSH", CHECK_NIX_FLAG_OR_ZERO(TCSAFLUSH)},
+    {NULL, 0}
+};
+
+static const struct ls_RegConst nix_console_i_flags[] = {
+    // Input flags (c_iflag)
+    {"I_IGNBRK", CHECK_NIX_FLAG_OR_ZERO(IGNBRK)},
+    {"I_BRKINT", CHECK_NIX_FLAG_OR_ZERO(BRKINT)},
+    {"I_IGNPAR", CHECK_NIX_FLAG_OR_ZERO(IGNPAR)},
+    {"I_PARMRK", CHECK_NIX_FLAG_OR_ZERO(PARMRK)},
+    {"I_INPCK", CHECK_NIX_FLAG_OR_ZERO(INPCK)},
+    {"I_ISTRIP", CHECK_NIX_FLAG_OR_ZERO(ISTRIP)},
+    {"I_INLCR", CHECK_NIX_FLAG_OR_ZERO(INLCR)},
+    {"I_IGNCR", CHECK_NIX_FLAG_OR_ZERO(IGNCR)},
+    {"I_ICRNL", CHECK_NIX_FLAG_OR_ZERO(ICRNL)},
+#ifndef __APPLE__
+    {"I_IUCLC", CHECK_NIX_FLAG_OR_ZERO(IUCLC)}, // Might not be available on all systems
+#else
+    {"I_IUCLC", 0},
+#endif
+    {"I_IXON", CHECK_NIX_FLAG_OR_ZERO(IXON)},
+    {"I_IXANY", CHECK_NIX_FLAG_OR_ZERO(IXANY)},
+    {"I_IXOFF", CHECK_NIX_FLAG_OR_ZERO(IXOFF)},
+    {"I_IMAXBEL", CHECK_NIX_FLAG_OR_ZERO(IMAXBEL)},
+    {NULL, 0}
 };
 
+static const struct ls_RegConst nix_console_o_flags[] = {
+    // Output flags (c_oflag)
+    {"O_OPOST", CHECK_NIX_FLAG_OR_ZERO(OPOST)},
+#ifndef __APPLE__
+    {"O_OLCUC", CHECK_NIX_FLAG_OR_ZERO(OLCUC)}, // Might not be available on all systems
+#else
+    {"O_OLCUC", 0},
+#endif
+    {"O_ONLCR", CHECK_NIX_FLAG_OR_ZERO(ONLCR)},
+    {"O_OCRNL", CHECK_NIX_FLAG_OR_ZERO(OCRNL)},
+    {"O_ONOCR", CHECK_NIX_FLAG_OR_ZERO(ONOCR)},
+    {"O_ONLRET", CHECK_NIX_FLAG_OR_ZERO(ONLRET)},
+    {"O_OFILL", CHECK_NIX_FLAG_OR_ZERO(OFILL)},
+    {"O_OFDEL", CHECK_NIX_FLAG_OR_ZERO(OFDEL)},
+    {"O_NLDLY", CHECK_NIX_FLAG_OR_ZERO(NLDLY)},
+    {"O_CRDLY", CHECK_NIX_FLAG_OR_ZERO(CRDLY)},
+    {"O_TABDLY", CHECK_NIX_FLAG_OR_ZERO(TABDLY)},
+    {"O_BSDLY", CHECK_NIX_FLAG_OR_ZERO(BSDLY)},
+    {"O_VTDLY", CHECK_NIX_FLAG_OR_ZERO(VTDLY)},
+    {"O_FFDLY", CHECK_NIX_FLAG_OR_ZERO(FFDLY)},
+    {NULL, 0}
+};
+
+static const struct ls_RegConst nix_console_l_flags[] = {
+    // Local flags (c_lflag)
+    {"L_ISIG", CHECK_NIX_FLAG_OR_ZERO(ISIG)},
+    {"L_ICANON", CHECK_NIX_FLAG_OR_ZERO(ICANON)},
+#ifndef __APPLE__
+    {"L_XCASE", CHECK_NIX_FLAG_OR_ZERO(XCASE)}, // Might not be available on all systems
+#else
+    {"L_XCASE", 0},
+#endif
+    {"L_ECHO", CHECK_NIX_FLAG_OR_ZERO(ECHO)},
+    {"L_ECHOE", CHECK_NIX_FLAG_OR_ZERO(ECHOE)},
+    {"L_ECHOK", CHECK_NIX_FLAG_OR_ZERO(ECHOK)},
+    {"L_ECHONL", CHECK_NIX_FLAG_OR_ZERO(ECHONL)},
+    {"L_NOFLSH", CHECK_NIX_FLAG_OR_ZERO(NOFLSH)},
+    {"L_TOSTOP", CHECK_NIX_FLAG_OR_ZERO(TOSTOP)},
+    {"L_ECHOCTL", CHECK_NIX_FLAG_OR_ZERO(ECHOCTL)}, // Might not be available on all systems
+    {"L_ECHOPRT", CHECK_NIX_FLAG_OR_ZERO(ECHOPRT)}, // Might not be available on all systems
+    {"L_ECHOKE", CHECK_NIX_FLAG_OR_ZERO(ECHOKE)}, // Might not be available on all systems
+    {"L_FLUSHO", CHECK_NIX_FLAG_OR_ZERO(FLUSHO)},
+    {"L_PENDIN", CHECK_NIX_FLAG_OR_ZERO(PENDIN)},
+    {"L_IEXTEN", CHECK_NIX_FLAG_OR_ZERO(IEXTEN)},
+    {NULL, 0}
+};
+
+static DWORD win_valid_in_flags = 0;
+static DWORD win_valid_out_flags = 0;
+static DWORD nix_valid_i_flags = 0;
+static DWORD nix_valid_o_flags = 0;
+static DWORD nix_valid_l_flags = 0;
+static void initialize_valid_flags()
+{
+    win_valid_in_flags = 0;
+    for (int i = 0; win_console_in_flags[i].name != NULL; i++)
+    {
+        win_valid_in_flags |= win_console_in_flags[i].value;
+    }
+    win_valid_out_flags = 0;
+    for (int i = 0; win_console_out_flags[i].name != NULL; i++)
+    {
+        win_valid_out_flags |= win_console_out_flags[i].value;
+    }
+    nix_valid_i_flags = 0;
+    for (int i = 0; nix_console_i_flags[i].name != NULL; i++)
+    {
+        nix_valid_i_flags |= nix_console_i_flags[i].value;
+    }
+    nix_valid_o_flags = 0;
+    for (int i = 0; nix_console_o_flags[i].name != NULL; i++)
+    {
+        nix_valid_o_flags |= nix_console_o_flags[i].value;
+    }
+    nix_valid_l_flags = 0;
+    for (int i = 0; nix_console_l_flags[i].name != NULL; i++)
+    {
+        nix_valid_l_flags |= nix_console_l_flags[i].value;
+    }
+}
+
+#ifdef _WIN32
+// first item on the stack should be io.stdin, io.stderr, or io.stdout, second item
+// should be the flags to validate.
+// If it returns NULL, then it leaves nil+err on the stack
+static HANDLE get_console_handle(lua_State *L, int flags_optional)
+{
+    if (lua_gettop(L) < 1) {
+        luaL_argerror(L, 1, "expected file handle");
+    }
+
+    HANDLE handle;
+    DWORD valid;
+    FILE *file = *(FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE);
+    if (file == stdin && file != NULL) {
+        handle = GetStdHandle(STD_INPUT_HANDLE);
+        valid = win_valid_in_flags;
+
+    } else if (file == stdout && file != NULL) {
+        handle =  GetStdHandle(STD_OUTPUT_HANDLE);
+        valid = win_valid_out_flags;
+
+    } else if (file == stderr && file != NULL) {
+        handle =  GetStdHandle(STD_ERROR_HANDLE);
+        valid = win_valid_out_flags;
+
+    } else {
+        luaL_argerror(L, 1, "invalid file handle"); // does not return
+    }
+
+    if (handle == INVALID_HANDLE_VALUE) {
+        termFormatError(L, GetLastError(), "failed to retrieve std handle");
+        lua_error(L); // does not return
+    }
+
+    if (handle == NULL) {
+        lua_pushnil(L);
+        lua_pushliteral(L, "failed to get console handle");
+        return NULL;
+    }
+
+    if (flags_optional && lua_gettop(L) < 2) {
+        return handle;
+    }
+
+    if (lua_gettop(L) < 2) {
+        luaL_argerror(L, 2, "expected flags");
+    }
+
+    LSBF_BITFLAG flags = lsbf_checkbitflags(L, 2);
+    if ((flags & ~valid) != 0) {
+        luaL_argerror(L, 2, "invalid flags");
+    }
+
+    return handle;
+}
+#else
+// first item on the stack should be io.stdin, io.stderr, or io.stdout. Throws a
+// Lua error if the file is not one of these.
+static int get_console_handle(lua_State *L)
+{
+    FILE **file = (FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE);
+    if (file == NULL || *file == NULL) {
+        return luaL_argerror(L, 1, "expected file handle"); // call doesn't return
+    }
+
+    // Check if the file is stdin, stdout, or stderr
+    if (*file == stdin || *file == stdout || *file == stderr) {
+        // Push the file descriptor onto the Lua stack
+        return fileno(*file);
+    }
+
+    return luaL_argerror(L, 1, "invalid file handle"); // does not return
+}
+#endif
+
+
+
+/***
+Sets the console flags (Windows).
+The `CIF_` and `COF_` constants are available on the module table. Where `CIF` are the
+input flags (for use with `io.stdin`) and `COF` are the output flags (for use with
+`io.stdout`/`io.stderr`).
+
+To see flag status and constant names check `listconsoleflags`.
+
+Note: not all combinations of flags are allowed, as some are mutually exclusive or mutually required.
+See [setconsolemode documentation](https://learn.microsoft.com/en-us/windows/console/setconsolemode)
+@function setconsoleflags
+@tparam file file file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@tparam bitflags bitflags the flags to set/unset
+@treturn[1] boolean `true` on success
+@treturn[2] nil
+@treturn[2] string error message
+@usage
+local system = require('system')
+system.listconsoleflags(io.stdout) -- List all the available flags and their current status
+
+local flags = system.getconsoleflags(io.stdout)
+assert(system.setconsoleflags(io.stdout,
+        flags + system.COF_VIRTUAL_TERMINAL_PROCESSING)
+
+system.listconsoleflags(io.stdout) -- List again to check the differences
+*/
+static int lst_setconsoleflags(lua_State *L)
+{
+#ifdef _WIN32
+    HANDLE console_handle = get_console_handle(L, 0);
+    if (console_handle == NULL) {
+        return 2; // error message is already on the stack
+    }
+    LSBF_BITFLAG new_console_mode = lsbf_checkbitflags(L, 2);
+
+    if (!SetConsoleMode(console_handle, new_console_mode)) {
+        termFormatError(L, GetLastError(), "failed to set console mode");
+        return 2;
+    }
+
+#else
+    get_console_handle(L); // to validate args
+#endif
+
+    lua_pushboolean(L, 1);
+    return 1;
+}
+
+
+
+/***
+Gets console flags (Windows).
+The `CIF_` and `COF_` constants are available on the module table. Where `CIF` are the
+input flags (for use with `io.stdin`) and `COF` are the output flags (for use with
+`io.stdout`/`io.stderr`).
+
+_Note_: See [setconsolemode documentation](https://learn.microsoft.com/en-us/windows/console/setconsolemode)
+for more information on the flags.
+
+
+
+@function getconsoleflags
+@tparam file file file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@treturn[1] bitflags the current console flags.
+@treturn[2] nil
+@treturn[2] string error message
+@usage
+local system = require('system')
+
+local flags = system.getconsoleflags(io.stdout)
+print("Current stdout flags:", tostring(flags))
+
+if flags:has_all_of(system.COF_VIRTUAL_TERMINAL_PROCESSING + system.COF_PROCESSED_OUTPUT) then
+    print("Both flags are set")
+else
+    print("At least one flag is not set")
+end
+*/
+static int lst_getconsoleflags(lua_State *L)
+{
+    DWORD console_mode = 0;
+
+#ifdef _WIN32
+    HANDLE console_handle = get_console_handle(L, 1);
+    if (console_handle == NULL) {
+        return 2; // error message is already on the stack
+    }
+
+    if (GetConsoleMode(console_handle, &console_mode) == 0)
+    {
+        lua_pushnil(L);
+        lua_pushliteral(L, "failed to get console mode");
+        return 2;
+    }
+#else
+    get_console_handle(L); // to validate args
+
+#endif
+    lsbf_pushbitflags(L, console_mode);
+    return 1;
+}
+
+
+
+/*-------------------------------------------------------------------------
+ * Unix tcgetattr/tcsetattr functions
+ *-------------------------------------------------------------------------*/
+// Code modified from the LuaPosix library by Gary V. Vaughan
+// see https://github.com/luaposix/luaposix
+
+/***
+Get termios state (Posix).
+The terminal attributes is a table with the following fields:
+
+- `iflag` input flags
+- `oflag` output flags
+- `lflag` local flags
+- `cflag` control flags
+- `ispeed` input speed
+- `ospeed` output speed
+- `cc` control characters
+
+@function tcgetattr
+@tparam file fd file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@treturn[1] termios terminal attributes, if successful. On Windows the bitflags are all 0, and the `cc` table is empty.
+@treturn[2] nil
+@treturn[2] string error message
+@treturn[2] int errnum
+@return error message if failed
+@usage
+local system = require('system')
+
+local status = assert(tcgetattr(io.stdin))
+if status.iflag:has_all_of(system.I_IGNBRK) then
+    print("Ignoring break condition")
+end
+*/
+static int lst_tcgetattr(lua_State *L)
+{
+#ifndef _WIN32
+    int r, i;
+    struct termios t;
+    int fd = get_console_handle(L);
+
+    r = tcgetattr(fd, &t);
+    if (r == -1) return pusherror(L, NULL);
+
+    lua_newtable(L);
+    lsbf_pushbitflags(L, t.c_iflag);
+    lua_setfield(L, -2, "iflag");
+
+    lsbf_pushbitflags(L, t.c_oflag);
+    lua_setfield(L, -2, "oflag");
+
+    lsbf_pushbitflags(L, t.c_lflag);
+    lua_setfield(L, -2, "lflag");
+
+    lsbf_pushbitflags(L, t.c_cflag);
+    lua_setfield(L, -2, "cflag");
+
+    lua_pushinteger(L, cfgetispeed(&t));
+    lua_setfield(L, -2, "ispeed");
+
+    lua_pushinteger(L, cfgetospeed(&t));
+    lua_setfield(L, -2, "ospeed");
+
+    lua_newtable(L);
+    for (i=0; i<NCCS; i++)
+    {
+        lua_pushinteger(L, i);
+        lua_pushinteger(L, t.c_cc[i]);
+        lua_settable(L, -3);
+    }
+    lua_setfield(L, -2, "cc");
+
+#else
+    lua_settop(L, 1); // remove all but file handle
+    get_console_handle(L, 1); //check args
+
+    lua_newtable(L);
+    lsbf_pushbitflags(L, 0);
+    lua_setfield(L, -2, "iflag");
+    lsbf_pushbitflags(L, 0);
+    lua_setfield(L, -2, "oflag");
+    lsbf_pushbitflags(L, 0);
+    lua_setfield(L, -2, "lflag");
+    lsbf_pushbitflags(L, 0);
+    lua_setfield(L, -2, "cflag");
+    lua_pushinteger(L, 0);
+    lua_setfield(L, -2, "ispeed");
+    lua_pushinteger(L, 0);
+    lua_setfield(L, -2, "ospeed");
+    lua_newtable(L);
+    lua_setfield(L, -2, "cc");
+
+#endif
+    return 1;
+}
+
+
+
+/***
+Set termios state (Posix).
+This function will set the flags as given.
+
+The `I_`, `O_`, and `L_` constants are available on the module table. They are the respective
+flags for the `iflags`, `oflags`, and `lflags` bitmasks.
+
+To see flag status and constant names check `listtermflags`. For their meaning check
+[the manpage](https://www.man7.org/linux/man-pages/man3/termios.3.html).
+
+_Note_: only `iflag`, `oflag`, and `lflag` are supported at the moment. The other fields are ignored.
+@function tcsetattr
+@tparam file fd file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@int actions one of `TCSANOW`, `TCSADRAIN`, `TCSAFLUSH`
+@tparam table termios a table with bitflag fields:
+@tparam[opt] bitflags termios.iflag if given will set the input flags
+@tparam[opt] bitflags termios.oflag if given will set the output flags
+@tparam[opt] bitflags termios.lflag if given will set the local flags
+@treturn[1] bool `true`, if successful. Always returns `true` on Windows.
+@return[2] nil
+@treturn[2] string error message
+@treturn[2] int errnum
+@usage
+local system = require('system')
+
+local status = assert(tcgetattr(io.stdin))
+if not status.lflag:has_all_of(system.L_ECHO) then
+    -- if echo is off, turn echoing newlines on
+    tcsetattr(io.stdin, system.TCSANOW, { lflag = status.lflag + system.L_ECHONL }))
+end
+*/
+static int lst_tcsetattr(lua_State *L)
+{
+#ifndef _WIN32
+    struct termios t;
+    int r, i;
+    int fd = get_console_handle(L);     // first is the console handle
+    int act = luaL_checkinteger(L, 2);  // second is the action to take
+
+    r = tcgetattr(fd, &t);
+    if (r == -1) return pusherror(L, NULL);
+
+    t.c_iflag = lsbf_checkbitflagsfield(L, 3, "iflag", t.c_iflag);
+    t.c_oflag = lsbf_checkbitflagsfield(L, 3, "oflag", t.c_oflag);
+    t.c_lflag = lsbf_checkbitflagsfield(L, 3, "lflag", t.c_lflag);
+
+    // Skipping the others for now
+
+    // lua_getfield(L, 3, "cflag"); t.c_cflag = optint(L, -1, 0); lua_pop(L, 1);
+    // lua_getfield(L, 3, "ispeed"); cfsetispeed( &t, optint(L, -1, B0) ); lua_pop(L, 1);
+    // lua_getfield(L, 3, "ospeed"); cfsetospeed( &t, optint(L, -1, B0) ); lua_pop(L, 1);
+
+    // lua_getfield(L, 3, "cc");
+    // for (i=0; i<NCCS; i++)
+    // {
+    //     lua_pushinteger(L, i);
+    //     lua_gettable(L, -2);
+    //     t.c_cc[i] = optint(L, -1, 0);
+    //     lua_pop(L, 1);
+    // }
+
+    r = tcsetattr(fd, act, &t);
+    if (r == -1) return pusherror(L, NULL);
+
+#else
+    // Windows does not have a tcsetattr function, but we check arguments anyway
+    luaL_checkinteger(L, 2);
+    lsbf_checkbitflagsfield(L, 3, "iflag", 0);
+    lsbf_checkbitflagsfield(L, 3, "oflag", 0);
+    lsbf_checkbitflagsfield(L, 3, "lflag", 0);
+    lua_settop(L, 1); // remove all but file handle
+    get_console_handle(L, 1);
+#endif
+
+    lua_pushboolean(L, 1);
+    return 1;
+}
+
+
+
+/***
+Enables or disables non-blocking mode for a file (Posix).
+@function setnonblock
+@tparam file fd file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@tparam boolean make_non_block a truthy value will enable non-blocking mode, a falsy value will disable it.
+@treturn[1] bool `true`, if successful
+@treturn[2] nil
+@treturn[2] string error message
+@treturn[2] int errnum
+@see getnonblock
+@usage
+local sys = require('system')
+
+-- set io.stdin to non-blocking mode
+local old_setting = sys.getnonblock(io.stdin)
+sys.setnonblock(io.stdin, true)
+
+-- do stuff
+
+-- restore old setting
+sys.setnonblock(io.stdin, old_setting)
+*/
+static int lst_setnonblock(lua_State *L)
+{
+#ifndef _WIN32
+
+    int fd = get_console_handle(L);
+
+    int flags = fcntl(fd, F_GETFL, 0);
+    if (flags == -1) {
+        return pusherror(L, "Error getting handle flags: ");
+    }
+    if (lua_toboolean(L, 2)) {
+        // truthy: set non-blocking
+        flags |= O_NONBLOCK;
+    } else {
+        // falsy: set disable non-blocking
+        flags &= ~O_NONBLOCK;
+    }
+    if (fcntl(fd, F_SETFL, flags) == -1) {
+        return pusherror(L, "Error changing O_NONBLOCK: ");
+    }
+
+#else
+    if (lua_gettop(L) > 1) {
+        lua_settop(L, 1); // use one argument, because the second boolean will fail as get_console_flags expects bitflags
+    }
+    HANDLE console_handle = get_console_handle(L, 1);
+    if (console_handle == NULL) {
+        return 2; // error message is already on the stack
+    }
+
+#endif
+
+    lua_pushboolean(L, 1);
+    return 1;
+}
+
+
+
+/***
+Gets non-blocking mode status for a file (Posix).
+@function getnonblock
+@tparam file fd file handle to operate on, one of `io.stdin`, `io.stdout`, `io.stderr`
+@treturn[1] bool `true` if set to non-blocking, `false` if not. Always returns `false` on Windows.
+@treturn[2] nil
+@treturn[2] string error message
+@treturn[2] int errnum
+*/
+static int lst_getnonblock(lua_State *L)
+{
+#ifndef _WIN32
+
+    int fd = get_console_handle(L);
+
+    // Set O_NONBLOCK
+    int flags = fcntl(fd, F_GETFL, 0);
+    if (flags == -1) {
+        return pusherror(L, "Error getting handle flags: ");
+    }
+    if (flags & O_NONBLOCK) {
+        lua_pushboolean(L, 1);
+    } else {
+        lua_pushboolean(L, 0);
+    }
+
+#else
+    if (lua_gettop(L) > 1) {
+        lua_settop(L, 1); // use one argument, because the second boolean will fail as get_console_flags expects bitflags
+    }
+    HANDLE console_handle = get_console_handle(L, 1);
+    if (console_handle == NULL) {
+        return 2; // error message is already on the stack
+    }
+
+    lua_pushboolean(L, 0);
+
+#endif
+    return 1;
+}
+
+
+
+/*-------------------------------------------------------------------------
+ * Reading keyboard input
+ *-------------------------------------------------------------------------*/
+
+#ifdef _WIN32
+// Define a static buffer for UTF-8 characters
+static char utf8_buffer[4];
+static int utf8_buffer_len = 0;
+static int utf8_buffer_index = 0;
+#endif
+
+
+/***
+Reads a key from the console non-blocking. This function should not be called
+directly, but through the `system.readkey` or `system.readansi` functions. It
+will return the next byte from the input stream, or `nil` if no key was pressed.
+
+On Posix, `io.stdin` must be set to non-blocking mode using `setnonblock`
+and canonical mode must be turned off using `tcsetattr`,
+before calling this function. Otherwise it will block. No conversions are
+done on Posix, so the byte read is returned as-is.
+
+On Windows this reads a wide character and converts it to UTF-8. Multi-byte
+sequences will be buffered internally and returned one byte at a time.
+
+@function _readkey
+@treturn[1] integer the byte read from the input stream
+@treturn[2] nil if no key was pressed
+@treturn[3] nil on error
+@treturn[3] string error message
+@treturn[3] int errnum (on posix)
+*/
+static int lst_readkey(lua_State *L) {
+#ifdef _WIN32
+    if (utf8_buffer_len > 0) {
+        // Buffer not empty, return the next byte
+        lua_pushinteger(L, (unsigned char)utf8_buffer[utf8_buffer_index]);
+        utf8_buffer_index++;
+        utf8_buffer_len--;
+        // printf("returning from buffer: %d\n", luaL_checkinteger(L, -1));
+        if (utf8_buffer_len == 0) {
+            utf8_buffer_index = 0;
+        }
+        return 1;
+    }
+
+    if (!_kbhit()) {
+        return 0;
+    }
+
+    wchar_t wc = _getwch();
+    // printf("----\nread wchar_t: %x\n", wc);
+    if (wc == WEOF) {
+        lua_pushnil(L);
+        lua_pushliteral(L, "read error");
+        return 2;
+    }
+
+    if (sizeof(wchar_t) == 2) {
+        // printf("2-byte wchar_t\n");
+        // only 2 bytes wide, not 4
+        if (wc >= 0xD800 && wc <= 0xDBFF) {
+            // printf("2-byte wchar_t, received high, getting low...\n");
+
+            // we got a high surrogate, so we need to read the next one as the low surrogate
+            if (!_kbhit()) {
+                lua_pushnil(L);
+                lua_pushliteral(L, "incomplete surrogate pair");
+                return 2;
+            }
+
+            wchar_t wc2 = _getwch();
+            // printf("read wchar_t 2: %x\n", wc2);
+            if (wc2 == WEOF) {
+                lua_pushnil(L);
+                lua_pushliteral(L, "read error");
+                return 2;
+            }
+
+            if (wc2 < 0xDC00 || wc2 > 0xDFFF) {
+                lua_pushnil(L);
+                lua_pushliteral(L, "invalid surrogate pair");
+                return 2;
+            }
+            // printf("2-byte pair complete now\n");
+            wchar_t wch_pair[2] = { wc, wc2 };
+            utf8_buffer_len = WideCharToMultiByte(CP_UTF8, 0, wch_pair, 2, utf8_buffer, sizeof(utf8_buffer), NULL, NULL);
+
+        } else {
+            // printf("2-byte wchar_t, no surrogate pair\n");
+            // not a high surrogate, so we can handle just the 2 bytes directly
+            utf8_buffer_len = WideCharToMultiByte(CP_UTF8, 0, &wc, 1, utf8_buffer, sizeof(utf8_buffer), NULL, NULL);
+        }
+
+    } else {
+        // printf("4-byte wchar_t\n");
+        // 4 bytes wide, so handle as UTF-32 directly
+        utf8_buffer_len = WideCharToMultiByte(CP_UTF8, 0, &wc, 1, utf8_buffer, sizeof(utf8_buffer), NULL, NULL);
+    }
+    // printf("utf8_buffer_len: %d\n", utf8_buffer_len);
+    utf8_buffer_index = 0;
+    if (utf8_buffer_len <= 0) {
+        lua_pushnil(L);
+        lua_pushliteral(L, "UTF-8 conversion error");
+        return 2;
+    }
+
+    lua_pushinteger(L, (unsigned char)utf8_buffer[utf8_buffer_index]);
+    utf8_buffer_index++;
+    utf8_buffer_len--;
+    // printf("returning from buffer: %x\n", luaL_checkinteger(L, -1));
+    return 1;
+
+#else
+    // Posix implementation
+    char ch;
+    ssize_t bytes_read = read(STDIN_FILENO, &ch, 1);
+    if (bytes_read > 0) {
+        lua_pushinteger(L, (unsigned char)ch);
+        return 1;
+
+    } else if (bytes_read == 0) {
+        return 0;  // End of file or stream closed
+
+    } else {
+        if (errno == EAGAIN || errno == EWOULDBLOCK) {
+            // Resource temporarily unavailable, no data available to read
+            return 0;
+        } else {
+            return pusherror(L, "read error");
+        }
+    }
+
+#endif
+}
+
+
+
+/*-------------------------------------------------------------------------
+ * Retrieve terminal size
+ *-------------------------------------------------------------------------*/
+
+
+/***
+Get the size of the terminal in rows and columns.
+@function termsize
+@treturn[1] int the number of rows
+@treturn[1] int the number of columns
+@treturn[2] nil
+@treturn[2] string error message
+*/
+static int lst_termsize(lua_State *L) {
+    int columns, rows;
+
+#ifdef _WIN32
+    CONSOLE_SCREEN_BUFFER_INFO csbi;
+    if (!GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi)) {
+        termFormatError(L, GetLastError(), "Failed to get terminal size.");
+        return 2;
+    }
+    columns = csbi.srWindow.Right - csbi.srWindow.Left + 1;
+    rows = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
+
+#else
+    struct winsize ws;
+    if (ioctl(1, TIOCGWINSZ, &ws) == -1) {
+        return pusherror(L, "Failed to get terminal size.");
+    }
+    columns = ws.ws_col;
+    rows = ws.ws_row;
+
+#endif
+    lua_pushinteger(L, rows);
+    lua_pushinteger(L, columns);
+    return 2;
+}
+
+
+
+/*-------------------------------------------------------------------------
+ * utf8 conversion and support
+ *-------------------------------------------------------------------------*/
+
+// Function to convert a single UTF-8 character to a Unicode code point (uint32_t)
+// To prevent having to do codepage/locale changes, we use a custom implementation
+int utf8_to_wchar(const char *utf8, size_t len, mk_wchar_t *codepoint) {
+    if (len == 0) {
+        return -1; // No input provided
+    }
+
+    unsigned char c = (unsigned char)utf8[0];
+    if (c <= 0x7F) {
+        *codepoint = c;
+        return 1;
+    } else if ((c & 0xE0) == 0xC0) {
+        if (len < 2) return -1; // Not enough bytes
+        *codepoint = ((utf8[0] & 0x1F) << 6) | (utf8[1] & 0x3F);
+        return 2;
+    } else if ((c & 0xF0) == 0xE0) {
+        if (len < 3) return -1; // Not enough bytes
+        *codepoint = ((utf8[0] & 0x0F) << 12) | ((utf8[1] & 0x3F) << 6) | (utf8[2] & 0x3F);
+        return 3;
+    } else if ((c & 0xF8) == 0xF0) {
+        if (len < 4) return -1; // Not enough bytes
+        *codepoint = ((utf8[0] & 0x07) << 18) | ((utf8[1] & 0x3F) << 12) | ((utf8[2] & 0x3F) << 6) | (utf8[3] & 0x3F);
+        return 4;
+    } else {
+        // Invalid UTF-8 character
+        return -1;
+    }
+}
+
+
+/***
+Get the width of a utf8 character for terminal display.
+@function utf8cwidth
+@tparam string utf8_char the utf8 character to check, only the width of the first character will be returned
+@treturn[1] int the display width in columns of the first character in the string (0 for an empty string)
+@treturn[2] nil
+@treturn[2] string error message
+*/
+int lst_utf8cwidth(lua_State *L) {
+    const char *utf8_char;
+    size_t utf8_len;
+    utf8_char = luaL_checklstring(L, 1, &utf8_len);
+    int width = 0;
+
+    mk_wchar_t wc;
+
+    if (utf8_len == 0) {
+        lua_pushinteger(L, 0);
+        return 1;
+    }
+
+    // Convert the UTF-8 string to a wide character
+    int bytes_processed = utf8_to_wchar(utf8_char, utf8_len, &wc);
+    if (bytes_processed == -1) {
+        lua_pushnil(L);
+        lua_pushstring(L, "Invalid UTF-8 character");
+        return 2;
+    }
+
+    // Get the width of the wide character
+    width = mk_wcwidth(wc);
+    if (width == -1) {
+        lua_pushnil(L);
+        lua_pushstring(L, "Character width determination failed");
+        return 2;
+    }
+
+    lua_pushinteger(L, width);
+    return 1;
+}
+
+
+
+
+/***
+Get the width of a utf8 string for terminal display.
+@function utf8swidth
+@tparam string utf8_string the utf8 string to check
+@treturn[1] int the display width of the string in columns (0 for an empty string)
+@treturn[2] nil
+@treturn[2] string error message
+*/
+int lst_utf8swidth(lua_State *L) {
+    const char *utf8_str;
+    size_t utf8_len;
+    utf8_str = luaL_checklstring(L, 1, &utf8_len);
+    int total_width = 0;
+
+    if (utf8_len == 0) {
+        lua_pushinteger(L, 0);
+        return 1;
+    }
+
+    int bytes_processed = 0;
+    size_t i = 0;
+    mk_wchar_t wc;
+
+    while (i < utf8_len) {
+        bytes_processed = utf8_to_wchar(utf8_str + i, utf8_len - i, &wc);
+        if (bytes_processed == -1) {
+            lua_pushnil(L);
+            lua_pushstring(L, "Invalid UTF-8 character");
+            return 2;
+        }
+
+        int width = mk_wcwidth(wc);
+        if (width == -1) {
+            lua_pushnil(L);
+            lua_pushstring(L, "Character width determination failed");
+            return 2;
+        }
+
+        total_width += width;
+        i += bytes_processed;
+    }
+
+    lua_pushinteger(L, total_width);
+    return 1;
+}
+
+
+
+/*-------------------------------------------------------------------------
+ * Windows codepage functions
+ *-------------------------------------------------------------------------*/
+
+
+/***
+Gets the current console code page (Windows).
+@function getconsolecp
+@treturn[1] int the current code page (always 65001 on Posix systems)
+*/
+static int lst_getconsolecp(lua_State *L) {
+    unsigned int cp = 65001;
+#ifdef _WIN32
+    cp = GetConsoleCP();
+#endif
+    lua_pushinteger(L, cp);
+    return 1;
+}
+
+
+
+/***
+Sets the current console code page (Windows).
+@function setconsolecp
+@tparam int cp the code page to set, use `system.CODEPAGE_UTF8` (65001) for UTF-8
+@treturn[1] bool `true` on success (always `true` on Posix systems)
+*/
+static int lst_setconsolecp(lua_State *L) {
+    unsigned int cp = (unsigned int)luaL_checkinteger(L, 1);
+    int success = TRUE;
+#ifdef _WIN32
+    SetConsoleCP(cp);
+#endif
+    lua_pushboolean(L, success);
+    return 1;
+}
+
+
+
+/***
+Gets the current console output code page (Windows).
+@function getconsoleoutputcp
+@treturn[1] int the current code page (always 65001 on Posix systems)
+*/
+static int lst_getconsoleoutputcp(lua_State *L) {
+    unsigned int cp = 65001;
+#ifdef _WIN32
+    cp = GetConsoleOutputCP();
+#endif
+    lua_pushinteger(L, cp);
+    return 1;
+}
+
+
+
+/***
+Sets the current console output code page (Windows).
+@function setconsoleoutputcp
+@tparam int cp the code page to set, use `system.CODEPAGE_UTF8` (65001) for UTF-8
+@treturn[1] bool `true` on success (always `true` on Posix systems)
+*/
+static int lst_setconsoleoutputcp(lua_State *L) {
+    unsigned int cp = (unsigned int)luaL_checkinteger(L, 1);
+    int success = TRUE;
+#ifdef _WIN32
+    SetConsoleOutputCP(cp);
+#endif
+    lua_pushboolean(L, success);
+    return 1;
+}
+
+
+
 /*-------------------------------------------------------------------------
  * Initializes module
  *-------------------------------------------------------------------------*/
+
+static luaL_Reg func[] = {
+    { "isatty", lst_isatty },
+    { "getconsoleflags", lst_getconsoleflags },
+    { "setconsoleflags", lst_setconsoleflags },
+    { "tcgetattr", lst_tcgetattr },
+    { "tcsetattr", lst_tcsetattr },
+    { "getnonblock", lst_getnonblock },
+    { "setnonblock", lst_setnonblock },
+    { "_readkey", lst_readkey },
+    { "termsize", lst_termsize },
+    { "utf8cwidth", lst_utf8cwidth },
+    { "utf8swidth", lst_utf8swidth },
+    { "getconsolecp", lst_getconsolecp },
+    { "setconsolecp", lst_setconsolecp },
+    { "getconsoleoutputcp", lst_getconsoleoutputcp },
+    { "setconsoleoutputcp", lst_setconsoleoutputcp },
+    { NULL, NULL }
+};
+
+
+
 void term_open(lua_State *L) {
+    // set up constants and export the constants in module table
+    initialize_valid_flags();
+    // Windows flags
+    for (int i = 0; win_console_in_flags[i].name != NULL; i++)
+    {
+        lsbf_pushbitflags(L, win_console_in_flags[i].value);
+        lua_setfield(L, -2, win_console_in_flags[i].name);
+    }
+    for (int i = 0; win_console_out_flags[i].name != NULL; i++)
+    {
+        lsbf_pushbitflags(L, win_console_out_flags[i].value);
+        lua_setfield(L, -2, win_console_out_flags[i].name);
+    }
+    // Unix flags
+    for (int i = 0; nix_console_i_flags[i].name != NULL; i++)
+    {
+        lsbf_pushbitflags(L, nix_console_i_flags[i].value);
+        lua_setfield(L, -2, nix_console_i_flags[i].name);
+    }
+    for (int i = 0; nix_console_o_flags[i].name != NULL; i++)
+    {
+        lsbf_pushbitflags(L, nix_console_o_flags[i].value);
+        lua_setfield(L, -2, nix_console_o_flags[i].name);
+    }
+    for (int i = 0; nix_console_l_flags[i].name != NULL; i++)
+    {
+        lsbf_pushbitflags(L, nix_console_l_flags[i].value);
+        lua_setfield(L, -2, nix_console_l_flags[i].name);
+    }
+    // Unix tcsetattr actions
+    for (int i = 0; nix_tcsetattr_actions[i].name != NULL; i++)
+    {
+        lua_pushinteger(L, nix_tcsetattr_actions[i].value);
+        lua_setfield(L, -2, nix_tcsetattr_actions[i].name);
+    }
+
+    // export functions
     luaL_setfuncs(L, func, 0);
 }
diff --git a/src/time.c b/src/time.c
index 5f0ead0..05f4f1b 100644
--- a/src/time.c
+++ b/src/time.c
@@ -1,4 +1,8 @@
-/// @submodule system
+/// @module system
+
+/// Time.
+// @section time
+
 #include <lua.h>
 #include <lauxlib.h>
 
diff --git a/src/wcwidth.c b/src/wcwidth.c
new file mode 100644
index 0000000..6032158
--- /dev/null
+++ b/src/wcwidth.c
@@ -0,0 +1,285 @@
+// This file was modified from the original versions, check "modified:" comments for details
+// Character range updates (both the table and the +1 check) were generated using ChatGPT.
+
+/*
+ * This is an implementation of wcwidth() and wcswidth() (defined in
+ * IEEE Std 1002.1-2001) for Unicode.
+ *
+ * http://www.opengroup.org/onlinepubs/007904975/functions/wcwidth.html
+ * http://www.opengroup.org/onlinepubs/007904975/functions/wcswidth.html
+ *
+ * In fixed-width output devices, Latin characters all occupy a single
+ * "cell" position of equal width, whereas ideographic CJK characters
+ * occupy two such cells. Interoperability between terminal-line
+ * applications and (teletype-style) character terminals using the
+ * UTF-8 encoding requires agreement on which character should advance
+ * the cursor by how many cell positions. No established formal
+ * standards exist at present on which Unicode character shall occupy
+ * how many cell positions on character terminals. These routines are
+ * a first attempt of defining such behavior based on simple rules
+ * applied to data provided by the Unicode Consortium.
+ *
+ * For some graphical characters, the Unicode standard explicitly
+ * defines a character-cell width via the definition of the East Asian
+ * FullWidth (F), Wide (W), Half-width (H), and Narrow (Na) classes.
+ * In all these cases, there is no ambiguity about which width a
+ * terminal shall use. For characters in the East Asian Ambiguous (A)
+ * class, the width choice depends purely on a preference of backward
+ * compatibility with either historic CJK or Western practice.
+ * Choosing single-width for these characters is easy to justify as
+ * the appropriate long-term solution, as the CJK practice of
+ * displaying these characters as double-width comes from historic
+ * implementation simplicity (8-bit encoded characters were displayed
+ * single-width and 16-bit ones double-width, even for Greek,
+ * Cyrillic, etc.) and not any typographic considerations.
+ *
+ * Much less clear is the choice of width for the Not East Asian
+ * (Neutral) class. Existing practice does not dictate a width for any
+ * of these characters. It would nevertheless make sense
+ * typographically to allocate two character cells to characters such
+ * as for instance EM SPACE or VOLUME INTEGRAL, which cannot be
+ * represented adequately with a single-width glyph. The following
+ * routines at present merely assign a single-cell width to all
+ * neutral characters, in the interest of simplicity. This is not
+ * entirely satisfactory and should be reconsidered before
+ * establishing a formal standard in this area. At the moment, the
+ * decision which Not East Asian (Neutral) characters should be
+ * represented by double-width glyphs cannot yet be answered by
+ * applying a simple rule from the Unicode database content. Setting
+ * up a proper standard for the behavior of UTF-8 character terminals
+ * will require a careful analysis not only of each Unicode character,
+ * but also of each presentation form, something the author of these
+ * routines has avoided to do so far.
+ *
+ * http://www.unicode.org/unicode/reports/tr11/
+ *
+ * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
+ *
+ * Permission to use, copy, modify, and distribute this software
+ * for any purpose and without fee is hereby granted. The author
+ * disclaims all warranties with regard to this software.
+ *
+ * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
+ */
+
+#include "wcwidth.h"  // modified: used to define mk_wchar_t
+
+struct interval {
+  int first;
+  int last;
+};
+
+/* auxiliary function for binary search in interval table */
+static int bisearch(mk_wchar_t ucs, const struct interval *table, int max) {  // modified: use mk_wchar_t
+  int min = 0;
+  int mid;
+
+  if (ucs < table[0].first || ucs > table[max].last)
+    return 0;
+  while (max >= min) {
+    mid = (min + max) / 2;
+    if (ucs > table[mid].last)
+      min = mid + 1;
+    else if (ucs < table[mid].first)
+      max = mid - 1;
+    else
+      return 1;
+  }
+
+  return 0;
+}
+
+
+/* The following two functions define the column width of an ISO 10646
+ * character as follows:
+ *
+ *    - The null character (U+0000) has a column width of 0.
+ *
+ *    - Other C0/C1 control characters and DEL will lead to a return
+ *      value of -1.
+ *
+ *    - Non-spacing and enclosing combining characters (general
+ *      category code Mn or Me in the Unicode database) have a
+ *      column width of 0.
+ *
+ *    - SOFT HYPHEN (U+00AD) has a column width of 1.
+ *
+ *    - Other format characters (general category code Cf in the Unicode
+ *      database) and ZERO WIDTH SPACE (U+200B) have a column width of 0.
+ *
+ *    - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF)
+ *      have a column width of 0.
+ *
+ *    - Spacing characters in the East Asian Wide (W) or East Asian
+ *      Full-width (F) category as defined in Unicode Technical
+ *      Report #11 have a column width of 2.
+ *
+ *    - All remaining characters (including all printable
+ *      ISO 8859-1 and WGL4 characters, Unicode control characters,
+ *      etc.) have a column width of 1.
+ *
+ * This implementation assumes that mk_wchar_t characters are encoded
+ * in ISO 10646.
+ */
+
+int mk_wcwidth(mk_wchar_t ucs)  // modified: use mk_wchar_t
+{
+  /* sorted list of non-overlapping intervals of non-spacing characters */
+  /* generated by "uniset +cat=Me +cat=Mn +cat=Cf -00AD +1160-11FF +200B c" */
+  static const struct interval combining[] = {  // modified: added new ranges to the list
+    { 0x0300, 0x036F }, { 0x0483, 0x0489 }, { 0x0591, 0x05BD },
+    { 0x05BF, 0x05BF }, { 0x05C1, 0x05C2 }, { 0x05C4, 0x05C5 },
+    { 0x05C7, 0x05C7 }, { 0x0600, 0x0605 }, { 0x0610, 0x061A },
+    { 0x061C, 0x061C }, { 0x064B, 0x065F }, { 0x0670, 0x0670 },
+    { 0x06D6, 0x06DC }, { 0x06DF, 0x06E4 }, { 0x06E7, 0x06E8 },
+    { 0x06EA, 0x06ED }, { 0x0711, 0x0711 }, { 0x0730, 0x074A },
+    { 0x07A6, 0x07B0 }, { 0x07EB, 0x07F3 }, { 0x07FD, 0x07FD },
+    { 0x0816, 0x0819 }, { 0x081B, 0x0823 }, { 0x0825, 0x0827 },
+    { 0x0829, 0x082D }, { 0x0859, 0x085B }, { 0x08D3, 0x08E1 },
+    { 0x08E3, 0x0903 }, { 0x093A, 0x093C }, { 0x093E, 0x094F },
+    { 0x0951, 0x0957 }, { 0x0962, 0x0963 }, { 0x0981, 0x0983 },
+    { 0x09BC, 0x09BC }, { 0x09BE, 0x09C4 }, { 0x09C7, 0x09C8 },
+    { 0x09CB, 0x09CD }, { 0x09D7, 0x09D7 }, { 0x09E2, 0x09E3 },
+    { 0x09FE, 0x09FE }, { 0x0A01, 0x0A03 }, { 0x0A3C, 0x0A3C },
+    { 0x0A3E, 0x0A42 }, { 0x0A47, 0x0A48 }, { 0x0A4B, 0x0A4D },
+    { 0x0A51, 0x0A51 }, { 0x0A70, 0x0A71 }, { 0x0A75, 0x0A75 },
+    { 0x0A81, 0x0A83 }, { 0x0ABC, 0x0ABC }, { 0x0ABE, 0x0AC5 },
+    { 0x0AC7, 0x0AC9 }, { 0x0ACB, 0x0ACD }, { 0x0AE2, 0x0AE3 },
+    { 0x0AFA, 0x0AFF }, { 0x0B01, 0x0B03 }, { 0x0B3C, 0x0B3C },
+    { 0x0B3E, 0x0B44 }, { 0x0B47, 0x0B48 }, { 0x0B4B, 0x0B4D },
+    { 0x0B55, 0x0B57 }, { 0x0B62, 0x0B63 }, { 0x0B82, 0x0B82 },
+    { 0x0BBE, 0x0BC2 }, { 0x0BC6, 0x0BC8 }, { 0x0BCA, 0x0BCD },
+    { 0x0BD7, 0x0BD7 }, { 0x0C00, 0x0C04 }, { 0x0C3E, 0x0C44 },
+    { 0x0C46, 0x0C48 }, { 0x0C4A, 0x0C4D }, { 0x0C55, 0x0C56 },
+    { 0x0C62, 0x0C63 }, { 0x0C81, 0x0C83 }, { 0x0CBC, 0x0CBC },
+    { 0x0CBE, 0x0CC4 }, { 0x0CC6, 0x0CC8 }, { 0x0CCA, 0x0CCD },
+    { 0x0CD5, 0x0CD6 }, { 0x0CE2, 0x0CE3 }, { 0x0D00, 0x0D03 },
+    { 0x0D3B, 0x0D3C }, { 0x0D3E, 0x0D44 }, { 0x0D46, 0x0D48 },
+    { 0x0D4A, 0x0D4D }, { 0x0D57, 0x0D57 }, { 0x0D62, 0x0D63 },
+    { 0x0D82, 0x0D83 }, { 0x0DCF, 0x0DD4 }, { 0x0DD6, 0x0DD6 },
+    { 0x0DD8, 0x0DDF }, { 0x0DF2, 0x0DF3 }, { 0x0E31, 0x0E31 },
+    { 0x0E34, 0x0E3A }, { 0x0E47, 0x0E4E }, { 0x0EB1, 0x0EB1 },
+    { 0x0EB4, 0x0EBC }, { 0x0EC8, 0x0ECD }, { 0x0F18, 0x0F19 },
+    { 0x0F35, 0x0F35 }, { 0x0F37, 0x0F37 }, { 0x0F39, 0x0F39 },
+    { 0x0F71, 0x0F7E }, { 0x0F80, 0x0F84 }, { 0x0F86, 0x0F87 },
+    { 0x0F8D, 0x0F97 }, { 0x0F99, 0x0FBC }, { 0x0FC6, 0x0FC6 },
+    { 0x102D, 0x1030 }, { 0x1032, 0x1037 }, { 0x1039, 0x103A },
+    { 0x103D, 0x103E }, { 0x1058, 0x1059 }, { 0x105E, 0x1060 },
+    { 0x1071, 0x1074 }, { 0x1082, 0x1082 }, { 0x1085, 0x1086 },
+    { 0x108D, 0x108D }, { 0x109D, 0x109D }, { 0x135D, 0x135F },
+    { 0x1712, 0x1714 }, { 0x1732, 0x1734 }, { 0x1752, 0x1753 },
+    { 0x1772, 0x1773 }, { 0x17B4, 0x17B5 }, { 0x17B7, 0x17BD },
+    { 0x17C6, 0x17C6 }, { 0x17C9, 0x17D3 }, { 0x17DD, 0x17DD },
+    { 0x180B, 0x180E }, { 0x1885, 0x1886 }, { 0x18A9, 0x18A9 },
+    { 0x1920, 0x1922 }, { 0x1927, 0x1928 }, { 0x1932, 0x1932 },
+    { 0x1939, 0x193B }, { 0x1A17, 0x1A18 }, { 0x1A1B, 0x1A1B },
+    { 0x1A56, 0x1A56 }, { 0x1A58, 0x1A5E }, { 0x1A60, 0x1A60 },
+    { 0x1A62, 0x1A62 }, { 0x1A65, 0x1A6C }, { 0x1A73, 0x1A7C },
+    { 0x1A7F, 0x1A7F }, { 0x1AB0, 0x1ACE }, { 0x1B00, 0x1B03 },
+    { 0x1B34, 0x1B34 }, { 0x1B36, 0x1B3A }, { 0x1B3C, 0x1B3C },
+    { 0x1B42, 0x1B42 }, { 0x1B6B, 0x1B73 }, { 0x1B80, 0x1B82 },
+    { 0x1BA1, 0x1BA1 }, { 0x1BA6, 0x1BA7 }, { 0x1BAA, 0x1BAA },
+    { 0x1BAB, 0x1BAD }, { 0x1BE6, 0x1BE6 }, { 0x1BE8, 0x1BE9 },
+    { 0x1BED, 0x1BED }, { 0x1BEF, 0x1BF1 }, { 0x1C2C, 0x1C33 },
+    { 0x1C36, 0x1C37 }, { 0x1CD0, 0x1CD2 }, { 0x1CD4, 0x1CE8 },
+    { 0x1CED, 0x1CED }, { 0x1CF4, 0x1CF4 }, { 0x1CF8, 0x1CF9 },
+    { 0x1DC0, 0x1DF9 }, { 0x1DFB, 0x1DFF }, { 0x20D0, 0x20DC },
+    { 0x20E1, 0x20E1 }, { 0x20E5, 0x20F0 }, { 0x2CEF, 0x2CF1 },
+    { 0x2D7F, 0x2D7F }, { 0x2DE0, 0x2DFF }, { 0x302A, 0x302D },
+    { 0x3099, 0x309A }, { 0xA66F, 0xA672 }, { 0xA674, 0xA67D },
+    { 0xA69E, 0xA69F }, { 0xA6F0, 0xA6F1 }, { 0xA802, 0xA802 },
+    { 0xA806, 0xA806 }, { 0xA80B, 0xA80B }, { 0xA825, 0xA826 },
+    { 0xA82C, 0xA82C }, { 0xA8C4, 0xA8C5 }, { 0xA8E0, 0xA8F1 },
+    { 0xA8FF, 0xA8FF }, { 0xA926, 0xA92D }, { 0xA947, 0xA951 },
+    { 0xA980, 0xA982 }, { 0xA9B3, 0xA9B3 }, { 0xA9B6, 0xA9B9 },
+    { 0xA9BC, 0xA9BD }, { 0xA9E5, 0xA9E5 }, { 0xAA29, 0xAA2E },
+    { 0xAA31, 0xAA32 }, { 0xAA35, 0xAA36 }, { 0xAA43, 0xAA43 },
+    { 0xAA4C, 0xAA4C }, { 0xAA7C, 0xAA7C }, { 0xAAB0, 0xAAB0 },
+    { 0xAAB2, 0xAAB4 }, { 0xAAB7, 0xAAB8 }, { 0xAABE, 0xAABF },
+    { 0xAAC1, 0xAAC1 }, { 0xAAEB, 0xAAEB }, { 0xAAEE, 0xAAEF },
+    { 0xAAF5, 0xAAF6 }, { 0xABE3, 0xABE4 }, { 0xABE6, 0xABE7 },
+    { 0xABE9, 0xABEA }, { 0xABEC, 0xABED }, { 0xFB1E, 0xFB1E },
+    { 0xFE00, 0xFE0F }, { 0xFE20, 0xFE2F }, { 0x101FD, 0x101FD },
+    { 0x102E0, 0x102E0 }, { 0x10376, 0x1037A }, { 0x10A01, 0x10A03 },
+    { 0x10A05, 0x10A06 }, { 0x10A0C, 0x10A0F }, { 0x10A38, 0x10A3A },
+    { 0x10A3F, 0x10A3F }, { 0x10AE5, 0x10AE6 }, { 0x10D24, 0x10D27 },
+    { 0x10EAB, 0x10EAC }, { 0x10F46, 0x10F50 }, { 0x10F82, 0x10F85 },
+    { 0x11000, 0x11002 }, { 0x11038, 0x11046 }, { 0x1107F, 0x11082 },
+    { 0x110B0, 0x110BA }, { 0x11100, 0x11102 }, { 0x11127, 0x11134 },
+    { 0x11145, 0x11146 }, { 0x11173, 0x11173 }, { 0x11180, 0x11182 },
+    { 0x111B3, 0x111C0 }, { 0x111C9, 0x111CC }, { 0x1122C, 0x11237 },
+    { 0x1123E, 0x1123E }, { 0x112DF, 0x112EA }, { 0x11300, 0x11303 },
+    { 0x1133B, 0x1133C }, { 0x1133E, 0x11344 }, { 0x11347, 0x11348 },
+    { 0x1134B, 0x1134D }, { 0x11357, 0x11357 }, { 0x11362, 0x11363 },
+    { 0x11435, 0x11446 }, { 0x1145E, 0x1145E }, { 0x114B0, 0x114C3 },
+    { 0x115AF, 0x115B5 }, { 0x115B8, 0x115C0 }, { 0x115DC, 0x115DD },
+    { 0x11630, 0x11640 }, { 0x116AB, 0x116B7 }, { 0x1171D, 0x1172B },
+    { 0x1182C, 0x1183A }, { 0x11930, 0x11935 }, { 0x11937, 0x11938 },
+    { 0x1193B, 0x1193E }, { 0x11940, 0x11940 }, { 0x11942, 0x11942 },
+    { 0x119D1, 0x119D7 }, { 0x119DA, 0x119E0 }, { 0x11A01, 0x11A0A },
+    { 0x11A33, 0x11A39 }, { 0x11A3B, 0x11A3E }, { 0x11A47, 0x11A47 },
+    { 0x11A51, 0x11A5B }, { 0x11A8A, 0x11A96 }, { 0x11A98, 0x11A99 },
+    { 0x11C30, 0x11C36 }, { 0x11C38, 0x11C3D }, { 0x11C3F, 0x11C3F },
+    { 0x11C92, 0x11CA7 }, { 0x11CAA, 0x11CB0 }, { 0x11CB2, 0x11CB3 },
+    { 0x11CB5, 0x11CB6 }, { 0x11D31, 0x11D36 }, { 0x11D3A, 0x11D3A },
+    { 0x11D3C, 0x11D3D }, { 0x11D3F, 0x11D45 }, { 0x11D47, 0x11D47 },
+    { 0x11D90, 0x11D91 }, { 0x11D95, 0x11D95 }, { 0x11D97, 0x11D97 },
+    { 0x11EF3, 0x11EF4 }, { 0x13430, 0x13438 }, { 0x16AF0, 0x16AF4 },
+    { 0x16B30, 0x16B36 }, { 0x16F4F, 0x16F4F }, { 0x16F8F, 0x16F92 },
+    { 0x1BC9D, 0x1BC9E }, { 0x1BCA0, 0x1BCA3 }, { 0x1D167, 0x1D169 },
+    { 0x1D173, 0x1D182 }, { 0x1D185, 0x1D18B }, { 0x1D1AA, 0x1D1AD },
+    { 0x1D242, 0x1D244 }, { 0x1DA00, 0x1DA36 }, { 0x1DA3B, 0x1DA6C },
+    { 0x1DA75, 0x1DA75 }, { 0x1DA84, 0x1DA84 }, { 0x1DA9B, 0x1DA9F },
+    { 0x1DAA1, 0x1DAAF }, { 0x1E000, 0x1E006 }, { 0x1E008, 0x1E018 },
+    { 0x1E01B, 0x1E021 }, { 0x1E023, 0x1E024 }, { 0x1E026, 0x1E02A },
+    { 0x1E130, 0x1E136 }, { 0x1E2AE, 0x1E2AE }, { 0x1E2EC, 0x1E2EF },
+    { 0x1E4EC, 0x1E4EF }, { 0x1E8D0, 0x1E8D6 }, { 0x1E944, 0x1E94A },
+    { 0x1E947, 0x1E94A }, { 0xE0100, 0xE01EF }
+  };
+
+  /* test for 8-bit control characters */
+  if (ucs == 0)
+    return 0;
+  if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
+    return -1;
+
+  /* binary search in table of non-spacing characters */
+  if (bisearch(ucs, combining,
+               sizeof(combining) / sizeof(struct interval) - 1))
+    return 0;
+
+  /* if we arrive here, ucs is not a combining or C0/C1 control character */
+
+  return 1 +
+    (ucs >= 0x1100 &&
+     (ucs <= 0x115f ||                    /* Hangul Jamo init. consonants */
+      ucs == 0x2329 || ucs == 0x232a ||
+      (ucs >= 0x2e80 && ucs <= 0xa4cf &&
+       ucs != 0x303f) ||                  /* CJK ... Yi */
+      (ucs >= 0xac00 && ucs <= 0xd7a3) || /* Hangul Syllables */
+      (ucs >= 0xf900 && ucs <= 0xfaff) || /* CJK Compatibility Ideographs */
+      (ucs >= 0xfe10 && ucs <= 0xfe19) || /* Vertical forms */
+      (ucs >= 0xfe30 && ucs <= 0xfe6f) || /* CJK Compatibility Forms */
+      (ucs >= 0xff00 && ucs <= 0xff60) || /* Fullwidth Forms */
+      (ucs >= 0xffe0 && ucs <= 0xffe6) ||
+      (ucs >= 0x1f300 && ucs <= 0x1f64f) || /* modified: added Emoticons */
+      (ucs >= 0x1f680 && ucs <= 0x1f6ff) || /* modified: added Transport and Map Symbols */
+      (ucs >= 0x1f900 && ucs <= 0x1f9ff) || /* modified: added Supplemental Symbols and Pictographs */
+      (ucs >= 0x20000 && ucs <= 0x2fffd) ||
+      (ucs >= 0x30000 && ucs <= 0x3fffd)));
+}
+
+
+int mk_wcswidth(const mk_wchar_t *pwcs, size_t n)  // modified: use mk_wchar_t
+{
+  int w, width = 0;
+
+  for (;*pwcs && n-- > 0; pwcs++)
+    if ((w = mk_wcwidth(*pwcs)) < 0)
+      return -1;
+    else
+      width += w;
+
+  return width;
+}
+
diff --git a/src/wcwidth.h b/src/wcwidth.h
new file mode 100644
index 0000000..f2fee11
--- /dev/null
+++ b/src/wcwidth.h
@@ -0,0 +1,21 @@
+// wcwidth.h
+
+// Windows does not have a wcwidth function, so we use compatibilty code from
+// http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c by Markus Kuhn
+
+#ifndef MK_WCWIDTH_H
+#define MK_WCWIDTH_H
+
+
+#ifdef _WIN32
+#include <stdint.h>
+typedef uint32_t mk_wchar_t; // Windows wchar_t can be 16-bit, we need 32-bit
+#else
+#include <wchar.h>
+typedef wchar_t mk_wchar_t;  // Posix wchar_t is 32-bit so just use that
+#endif
+
+int mk_wcwidth(mk_wchar_t ucs);
+int mk_wcswidth(const mk_wchar_t *pwcs, size_t n);
+
+#endif // MK_WCWIDTH_H