add initial implementation of c-api and license

5 files changed, 1099 insertions, 0 deletions

diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..511db15
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Kepler Project.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/c-api/compat-5.3.c b/c-api/compat-5.3.c
new file mode 100644
index 0000000..9edd5f1
--- /dev/null
+++ b/c-api/compat-5.3.c
@@ -0,0 +1,430 @@
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <lua.h>
+#include <lauxlib.h>
+#include "compat-5.3.h"
+
+/* don't compile it again if it already is included via compat53.h */
+#ifndef COMPAT53_C_
+#define COMPAT53_C_
+
+
+
+/* definitions for Lua 5.1 only */
+#if defined( LUA_VERSION_NUM ) && LUA_VERSION_NUM == 501
+
+
+COMPAT53_API int lua_absindex (lua_State *L, int i) {
+  if (i < 0 && i > LUA_REGISTRYINDEX)
+    i += lua_gettop(L) + 1;
+  return i;
+}
+
+
+COMPAT53_API void lua_copy (lua_State *L, int from, int to) {
+  int abs_to = lua_absindex(L, to);
+  luaL_checkstack(L, 1, "not enough stack slots");
+  lua_pushvalue(L, from);
+  lua_replace(L, abs_to);
+}
+
+
+COMPAT53_API void lua_len (lua_State *L, int i) {
+  switch (lua_type(L, i)) {
+    case LUA_TSTRING: /* fall through */
+    case LUA_TTABLE:
+      lua_pushnumber(L, (int)lua_objlen(L, i));
+      break;
+    case LUA_TUSERDATA:
+      if (luaL_callmeta(L, i, "__len"))
+        break;
+      /* maybe fall through */
+    default:
+      luaL_error(L, "attempt to get length of a %s value",
+                 lua_typename(L, lua_type(L, i)));
+  }
+}
+
+
+COMPAT53_API int lua_rawgetp (lua_State *L, int i, const void *p) {
+  int abs_i = lua_absindex(L, i);
+  lua_pushlightuserdata(L, (void*)p);
+  lua_rawget(L, abs_i);
+  return lua_type(L, -1);
+}
+
+COMPAT53_API void lua_rawsetp (lua_State *L, int i, const void *p) {
+  int abs_i = lua_absindex(L, i);
+  luaL_checkstack(L, 1, "not enough stack slots");
+  lua_pushlightuserdata(L, (void*)p);
+  lua_insert(L, -2);
+  lua_rawset(L, abs_i);
+}
+
+
+COMPAT53_API lua_Integer lua_tointegerx (lua_State *L, int i, int *isnum) {
+  lua_Integer n = lua_tointeger(L, i);
+  if (isnum != NULL) {
+    *isnum = (n != 0 || lua_isnumber(L, i));
+}
+  return n;
+}
+
+
+COMPAT53_API lua_Number lua_tonumberx (lua_State *L, int i, int *isnum) {
+  lua_Number n = lua_tonumber(L, i);
+  if (isnum != NULL) {
+    *isnum = (n != 0 || lua_isnumber(L, i));
+  }
+  return n;
+}
+
+
+COMPAT53_API void luaL_checkversion (lua_State *L) {
+  (void)L;
+}
+
+
+COMPAT53_API int luaL_getsubtable (lua_State *L, int i, const char *name) {
+  int abs_i = lua_absindex(L, i);
+  luaL_checkstack(L, 3, "not enough stack slots");
+  lua_pushstring(L, name);
+  lua_gettable(L, abs_i);
+  if (lua_istable(L, -1))
+    return 1;
+  lua_pop(L, 1);
+  lua_newtable(L);
+  lua_pushstring(L, name);
+  lua_pushvalue(L, -2);
+  lua_settable(L, abs_i);
+  return 0;
+}
+
+
+COMPAT53_API int luaL_len (lua_State *L, int i) {
+  int res = 0, isnum = 0;
+  luaL_checkstack(L, 1, "not enough stack slots");
+  lua_len(L, i);
+  res = (int)lua_tointegerx(L, -1, &isnum);
+  lua_pop(L, 1);
+  if (!isnum)
+    luaL_error(L, "object length is not a number");
+  return res;
+}
+
+
+COMPAT53_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
+  luaL_checkstack(L, nup+1, "too many upvalues");
+  for (; l->name != NULL; l++) {  /* fill the table with given functions */
+    int i;
+    lua_pushstring(L, l->name);
+    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -(nup + 1));
+    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
+    lua_settable(L, -(nup + 3)); /* table must be below the upvalues, the name and the closure */
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+COMPAT53_API void luaL_setmetatable (lua_State *L, const char *tname) {
+  luaL_checkstack(L, 1, "not enough stack slots");
+  luaL_getmetatable(L, tname);
+  lua_setmetatable(L, -2);
+}
+
+
+COMPAT53_API void *luaL_testudata (lua_State *L, int i, const char *tname) {
+  void *p = lua_touserdata(L, i);
+  luaL_checkstack(L, 2, "not enough stack slots");
+  if (p == NULL || !lua_getmetatable(L, i))
+    return NULL;
+  else {
+    int res = 0;
+    luaL_getmetatable(L, tname);
+    res = lua_rawequal(L, -1, -2);
+    lua_pop(L, 2);
+    if (!res)
+      p = NULL;
+  }
+  return p;
+}
+
+
+COMPAT53_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
+  if (!luaL_callmeta(L, idx, "__tostring")) {
+    int t = lua_type(L, idx);
+    switch (t) {
+      case LUA_TNIL:
+        lua_pushliteral(L, "nil");
+        break;
+      case LUA_TSTRING:
+      case LUA_TNUMBER:
+        lua_pushvalue(L, idx);
+        break;
+      case LUA_TBOOLEAN:
+        if (lua_toboolean(L, idx))
+          lua_pushliteral(L, "true");
+        else
+          lua_pushliteral(L, "false");
+        break;
+      default:
+        lua_pushfstring(L, "%s: %p", lua_typename(L, t),
+                                     lua_topointer(L, idx));
+        break;
+    }
+  }
+  return lua_tolstring(L, -1, len);
+}
+
+
+#if !defined(COMPAT53_IS_LUAJIT)
+static int compat53_countlevels (lua_State *L) {
+  lua_Debug ar;
+  int li = 1, le = 1;
+  /* find an upper bound */
+  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
+  /* do a binary search */
+  while (li < le) {
+    int m = (li + le)/2;
+    if (lua_getstack(L, m, &ar)) li = m + 1;
+    else le = m;
+  }
+  return le - 1;
+}
+
+static int compat53_findfield (lua_State *L, int objidx, int level) {
+  if (level == 0 || !lua_istable(L, -1))
+    return 0;  /* not found */
+  lua_pushnil(L);  /* start 'next' loop */
+  while (lua_next(L, -2)) {  /* for each pair in table */
+    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */
+      if (lua_rawequal(L, objidx, -1)) {  /* found object? */
+        lua_pop(L, 1);  /* remove value (but keep name) */
+        return 1;
+      }
+      else if (compat53_findfield(L, objidx, level - 1)) {  /* try recursively */
+        lua_remove(L, -2);  /* remove table (but keep name) */
+        lua_pushliteral(L, ".");
+        lua_insert(L, -2);  /* place '.' between the two names */
+        lua_concat(L, 3);
+        return 1;
+      }
+    }
+    lua_pop(L, 1);  /* remove value */
+  }
+  return 0;  /* not found */
+}
+
+static int compat53_pushglobalfuncname (lua_State *L, lua_Debug *ar) {
+  int top = lua_gettop(L);
+  lua_getinfo(L, "f", ar);  /* push function */
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  if (compat53_findfield(L, top + 1, 2)) {
+    lua_copy(L, -1, top + 1);  /* move name to proper place */
+    lua_pop(L, 2);  /* remove pushed values */
+    return 1;
+  }
+  else {
+    lua_settop(L, top);  /* remove function and global table */
+    return 0;
+  }
+}
+
+static void compat53_pushfuncname (lua_State *L, lua_Debug *ar) {
+  if (*ar->namewhat != '\0')  /* is there a name? */
+    lua_pushfstring(L, "function " LUA_QS, ar->name);
+  else if (*ar->what == 'm')  /* main? */
+      lua_pushliteral(L, "main chunk");
+  else if (*ar->what == 'C') {
+    if (compat53_pushglobalfuncname(L, ar)) {
+      lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1));
+      lua_remove(L, -2);  /* remove name */
+    }
+    else
+      lua_pushliteral(L, "?");
+  }
+  else
+    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
+}
+
+#define COMPAT53_LEVELS1 12  /* size of the first part of the stack */
+#define COMPAT53_LEVELS2 10  /* size of the second part of the stack */
+
+COMPAT53_API void luaL_traceback (lua_State *L, lua_State *L1,
+                                  const char *msg, int level) {
+  lua_Debug ar;
+  int top = lua_gettop(L);
+  int numlevels = compat53_countlevels(L1);
+  int mark = (numlevels > COMPAT53_LEVELS1 + COMPAT53_LEVELS2) ? COMPAT53_LEVELS1 : 0;
+  if (msg) lua_pushfstring(L, "%s\n", msg);
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (level == mark) {  /* too many levels? */
+      lua_pushliteral(L, "\n\t...");  /* add a '...' */
+      level = numlevels - COMPAT53_LEVELS2;  /* and skip to last ones */
+    }
+    else {
+      lua_getinfo(L1, "Slnt", &ar);
+      lua_pushfstring(L, "\n\t%s:", ar.short_src);
+      if (ar.currentline > 0)
+        lua_pushfstring(L, "%d:", ar.currentline);
+      lua_pushliteral(L, " in ");
+      compat53_pushfuncname(L, &ar);
+      lua_concat(L, lua_gettop(L) - top);
+    }
+  }
+  lua_concat(L, lua_gettop(L) - top);
+}
+
+
+COMPAT53_API int luaL_fileresult (lua_State *L, int stat, const char *fname) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (stat) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    if (fname)
+      lua_pushfstring(L, "%s: %s", fname, strerror(en));
+    else
+      lua_pushstring(L, strerror(en));
+    lua_pushnumber(L, (lua_Number)en);
+    return 3;
+  }
+}
+#endif /* not COMPAT53_IS_LUAJIT */
+
+
+#endif /* Lua 5.1 */
+
+
+
+/* definitions for Lua 5.1 and Lua 5.2 */
+#if defined( LUA_VERSION_NUM ) && LUA_VERSION_NUM <= 502
+
+
+COMPAT53_API int lua_geti (lua_State *L, int index, lua_Integer i) {
+  index = lua_absindex(L, index);
+  lua_pushinteger(L, i);
+  lua_gettable(L, index);
+  return lua_type(L, -1);
+}
+
+
+COMPAT53_API int lua_isinteger (lua_State *L, int index) {
+  if (lua_type(L, index) == LUA_TNUMBER) {
+    lua_Number n = lua_tonumber(L, index);
+    lua_Integer i = lua_tointeger(L, index);
+    if (i == n)
+      return 1;
+  }
+  return 0;
+}
+
+
+static void compat53_reverse (lua_State *L, int a, int b) {
+  for (; a < b; ++a, --b) {
+    lua_pushvalue(L, a);
+    lua_pushvalue(L, b);
+    lua_replace(L, a);
+    lua_replace(L, b);
+  }
+}
+
+
+COMPAT53_API void lua_rotate (lua_State *L, int idx, int n) {
+  int n_elems = 0;
+  idx = lua_absindex(L, idx);
+  n_elems = lua_gettop(L)-idx+1;
+  if (n < 0)
+    n += n_elems;
+  if ( n > 0 && n < n_elems) {
+    luaL_checkstack(L, 2, "not enough stack slots available");
+    n = n_elems - n;
+    compat53_reverse(L, idx, idx+n-1);
+    compat53_reverse(L, idx+n, idx+n_elems-1);
+    compat53_reverse(L, idx, idx+n_elems-1);
+  }
+}
+
+
+COMPAT53_API void lua_seti (lua_State *L, int index, lua_Integer i) {
+  luaL_checkstack(L, 1, "not enough stack slots available");
+  index = lua_absindex(L, index);
+  lua_pushinteger(L, i);
+  lua_insert(L, -2);
+  lua_settable(L, index);
+}
+
+
+COMPAT53_API size_t lua_stringtonumber (lua_State *L, const char *s) {
+  char* endptr;
+  lua_Number n = lua_str2number(s, &endptr);
+  if (endptr != s) {
+    while (*endptr != '\0' && isspace((unsigned char)*endptr))
+      ++endptr;
+    if (*endptr == '\0') {
+      lua_pushnumber(L, n);
+      return endptr - s + 1;
+    }
+  }
+  return 0;
+}
+
+
+COMPAT53_API void luaL_requiref (lua_State *L, const char *modname,
+                                 lua_CFunction openf, int glb) {
+  luaL_checkstack(L, 3, "not enough stack slots available");
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  if (lua_getfield(L, -1, modname) == LUA_TNIL) {
+    lua_pop(L, 1);
+    lua_pushcfunction(L, openf);
+    lua_pushstring(L, modname);
+    lua_call(L, 1, 1);
+    lua_pushvalue(L, -1);
+    lua_setfield(L, -3, modname);
+  }
+  if (glb) {
+    lua_pushvalue(L, -1);
+    lua_setglobal(L, modname);
+  }
+  lua_replace(L, -2);
+}
+
+
+#endif /* Lua 5.1 and 5.2 */
+
+
+#endif /* COMPAT53_C_ */
+
+
+/*********************************************************************
+* This file contains parts of Lua 5.2's and Lua 5.3's source code:
+*
+* Copyright (C) 1994-2014 Lua.org, PUC-Rio.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*********************************************************************/
+
diff --git a/c-api/compat-5.3.h b/c-api/compat-5.3.h
new file mode 100644
index 0000000..b288126
--- /dev/null
+++ b/c-api/compat-5.3.h
@@ -0,0 +1,294 @@
+#ifndef COMPAT53_H_
+#define COMPAT53_H_
+
+#include <stddef.h>
+#include <limits.h>
+#include <lua.h>
+#include <lauxlib.h>
+#include <lualib.h>
+
+
+#if defined(COMPAT53_PREFIX)
+/* - change the symbol names of functions to avoid linker conflicts
+ * - compat-5.3.c needs to be compiled (and linked) separately
+ */
+#  if !defined(COMPAT53_API)
+#    define COMPAT53_API extern
+#  endif
+#  undef COMPAT53_INCLUDE_SOURCE
+#else /* COMPAT53_PREFIX */
+/* - make all functions static and include the source.
+ * - don't mess with the symbol names of functions
+ * - compat-5.3.c doesn't need to be compiled (and linked) separately
+ */
+#  define COMPAT53_PREFIX lua
+#  undef COMPAT53_API
+#  if defined(__GNUC__) || defined(__clang__)
+#    define COMPAT53_API __attribute__((__unused__)) static
+#  else
+#    define COMPAT53_API static
+#  endif
+#  define COMPAT53_INCLUDE_SOURCE
+#endif /* COMPAT53_PREFIX */
+
+#define COMPAT53_CONCAT_HELPER(a, b) a##b
+#define COMPAT53_CONCAT(a, b) COMPAT53_CONCAT_HELPER(a, b)
+
+
+
+/* declarations for Lua 5.1 */
+#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 501
+
+/* XXX not implemented:
+ * lua_arith
+ * lua_compare
+ * lua_upvalueid
+ * lua_upvaluejoin
+ * lua_version
+ * lua_yieldk
+ * luaL_buffinitsize
+ * luaL_execresult
+ * luaL_loadbufferx
+ * luaL_loadfilex
+ * luaL_prepbuffsize
+ * luaL_pushresultsize
+ */
+
+/* PUC-Rio Lua uses lconfig_h as include guard for luaconf.h,
+ * LuaJIT uses luaconf_h. If you use PUC-Rio's include files
+ * but LuaJIT's library, you will need to define the macro
+ * COMPAT53_IS_LUAJIT yourself! */
+#if !defined(COMPAT53_IS_LUAJIT) && defined(luaconf_h)
+#  define COMPAT53_IS_LUAJIT
+#endif
+
+#define LUA_OK 0
+
+typedef struct luaL_Stream {
+  FILE *f;
+  lua_CFunction closef;
+} luaL_Stream;
+
+typedef size_t lua_Unsigned;
+
+#define lua_absindex COMPAT53_CONCAT(COMPAT53_PREFIX, _absindex)
+COMPAT53_API int lua_absindex (lua_State *L, int i);
+
+#define lua_copy COMPAT53_CONCAT(COMPAT53_PREFIX, _copy)
+COMPAT53_API void lua_copy (lua_State *L, int from, int to);
+
+#define lua_getuservalue(L, i) \
+  (lua_getfenv(L, i), lua_type(L, -1))
+#define lua_setuservalue(L, i) \
+  (luaL_checktype(L, -1, LUA_TTABLE), lua_setfenv(L, i))
+
+#define lua_len COMPAT53_CONCAT(COMPAT53_PREFIX, _len)
+COMPAT53_API void lua_len (lua_State *L, int i);
+
+#define luaL_newlibtable(L, l) \
+  (lua_createtable(L, 0, sizeof(l)/sizeof(*(l))-1))
+#define luaL_newlib(L, l) \
+  (luaL_newlibtable(L, l), luaL_register(L, NULL, l))
+
+#define lua_pushglobaltable(L) \
+  lua_pushvalue(L, LUA_GLOBALSINDEX)
+
+#define lua_rawgetp COMPAT53_CONCAT(COMPAT53_PREFIX, _rawgetp)
+COMPAT53_API int lua_rawgetp (lua_State *L, int i, const void *p);
+
+#define lua_rawsetp COMPAT53_CONCAT(COMPAT53_PREFIX, _rawsetp)
+COMPAT53_API void lua_rawsetp(lua_State *L, int i, const void *p);
+
+#define lua_rawlen(L, i) lua_objlen(L, i)
+
+#define lua_tointegerx COMPAT53_CONCAT(COMPAT53_PREFIX, _tointegerx)
+COMPAT53_API lua_Integer lua_tointegerx (lua_State *L, int i, int *isnum);
+
+#define lua_tonumberx COMPAT53_CONCAT(COMPAT53_PREFIX, _tonumberx)
+COMPAT53_API lua_Number lua_tonumberx (lua_State *L, int i, int *isnum);
+
+#define luaL_checkversion COMPAT53_CONCAT(COMPAT53_PREFIX, L_checkversion)
+COMPAT53_API void luaL_checkversion (lua_State *L);
+
+#define luaL_getsubtable COMPAT53_CONCAT(COMPAT53_PREFIX, L_getsubtable)
+COMPAT53_API int luaL_getsubtable (lua_State* L, int i, const char *name);
+
+#define luaL_len COMPAT53_CONCAT(COMPAT53_PREFIX, L_len)
+COMPAT53_API int luaL_len (lua_State *L, int i);
+
+#define luaL_setfuncs COMPAT53_CONCAT(COMPAT53_PREFIX, L_setfuncs)
+COMPAT53_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);
+
+#define luaL_setmetatable COMPAT53_CONCAT(COMPAT53_PREFIX, L_setmetatable)
+COMPAT53_API void luaL_setmetatable (lua_State *L, const char *tname);
+
+#define luaL_testudata COMPAT53_CONCAT(COMPAT53_PREFIX, L_testudata)
+COMPAT53_API void *luaL_testudata (lua_State *L, int i, const char *tname);
+
+#define luaL_tolstring COMPAT53_CONCAT(COMPAT53_PREFIX, L_tolstring)
+COMPAT53_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len);
+
+#if !defined(COMPAT53_IS_LUAJIT)
+#define luaL_traceback COMPAT53_CONCAT(COMPAT53_PREFIX, L_traceback)
+COMPAT53_API void luaL_traceback (lua_State *L, lua_State *L1, const char *msg, int level);
+
+#define luaL_fileresult COMPAT53_CONCAT(COMPAT53_PREFIX, L_fileresult)
+COMPAT53_API int luaL_fileresult (lua_State *L, int stat, const char *fname);
+#endif /* COMPAT53_IS_LUAJIT */
+
+#define lua_callk(L, na, nr, ctx, cont) \
+  ((void)(ctx), (void)(cont), lua_call(L, na, nr))
+#define lua_pcallk(L, na, nr, err, ctx, cont) \
+  ((void)(ctx), (void)(cont), lua_pcall(L, na, nr, err))
+
+#if defined(LUA_COMPAT_APIINTCASTS)
+#define lua_pushunsigned(L, n) \
+  lua_pushinteger(L, (lua_Integer)(n))
+#define lua_tounsignedx(L, i, is) \
+  ((lua_Unsigned)lua_tointegerx(L, i, is))
+#define lua_tounsigned(L, i) \
+  lua_tounsignedx(L, i, NULL)
+#define luaL_checkunsigned(L, a) \
+  ((lua_Unsigned)luaL_checkinteger(L, a))
+#define luaL_optunsigned(L, a, d) \
+  ((lua_Unsigned)luaL_optinteger(L, a, (lua_Integer)(d)))
+#endif
+
+#endif /* Lua 5.1 only */
+
+
+
+/* declarations for Lua 5.1 and 5.2 */
+#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM <= 502
+
+typedef int lua_KContext;
+
+typedef int (*lua_KFunction)(lua_State *L, int status, lua_KContext ctx);
+
+#define lua_dump(L, w, d, s) \
+  ((void)(s), lua_dump(L, w, d))
+
+#define lua_getfield(L, i, k) \
+  (lua_getfield(L, i, k), lua_type(L, -1))
+
+#define lua_gettable(L, i) \
+  (lua_gettable(L, i), lua_type(L, -1))
+
+#define lua_geti COMPAT53_CONCAT(COMPAT53_PREFIX, _geti)
+COMPAT53_API int lua_geti (lua_State *L, int index, lua_Integer i);
+
+#define lua_isinteger COMPAT53_CONCAT(COMPAT53_PREFIX, _isinteger)
+COMPAT53_API int lua_isinteger (lua_State *L, int index);
+
+#define lua_numbertointeger(n, p) \
+  ((*(p) = (lua_Integer)(n)), 1)
+
+#define lua_rawget(L, i) \
+  (lua_rawget(L, i), lua_type(L, -1))
+
+#define lua_rawgeti(L, i, n) \
+  (lua_rawgeti(L, i, n), lua_type(L, -1))
+
+#define lua_rotate COMPAT53_CONCAT(COMPAT53_PREFIX, _rotate)
+COMPAT53_API void lua_rotate (lua_State *L, int idx, int n);
+
+#define lua_seti COMPAT53_CONCAT(COMPAT53_PREFIX, _seti)
+COMPAT53_API void lua_seti (lua_State *L, int index, lua_Integer i);
+
+#define lua_strtonum COMPAT53_CONCAT(COMPAT53_PREFIX, _stringtonumber)
+COMPAT53_API size_t lua_stringtonumber (lua_State *L, const char *s);
+
+#define luaL_getmetafield(L, o, e) \
+  (luaL_getmetafield(L, o, e) ? lua_type(L, -1) : LUA_TNIL)
+
+#define luaL_requiref COMPAT53_CONCAT(COMPAT53_PREFIX, L_requiref_)
+COMPAT53_API void luaL_requiref (lua_State *L, const char *modname,
+                                 lua_CFunction openf, int glb );
+
+#endif /* Lua 5.1 and Lua 5.2 */
+
+
+
+/* declarations for Lua 5.2 */
+#if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM == 502
+
+/* XXX not implemented:
+ * lua_isyieldable
+ * lua_getextraspace
+ * lua_arith (new operators)
+ * lua_pushfstring (new formats)
+ */
+
+#define lua_getglobal(L, n) \
+  (lua_getglobal(L, n), lua_type(L, -1))
+
+#define lua_getuservalue(L, i) \
+  (lua_getuservalue(L, i), lua_type(L, -1))
+
+#define lua_rawgetp(L, i, p) \
+  (lua_rawgetp(L, i, p), lua_type(L, -1))
+
+#define LUA_KFUNCTION(_name) \
+  static int (_name)(lua_State *L, int status, lua_KContext ctx); \
+  static int (_name ## _52)(lua_State *L) { \
+    luaK_Context ctx; \
+    int status = lua_getctx(L, &ctx); \
+    return (_name)(L, status, ctx); \
+  } \
+  static int (_name)(lua_State *L, int status, lua_KContext ctx)
+
+#define lua_pcallk(L, na, nr, err, ctx, cont) \
+  lua_pcallk(L, na, nr, err, ctx, cont ## _52)
+
+#define lua_callk(L, na, nr, ctx, cont) \
+  lua_callk(L, na, nr, ctx, cont ## _52)
+
+#define lua_yieldk(L, nr, ctx, cont) \
+  lua_yieldk(L, nr, ctx, cont ## _52)
+
+#ifdef lua_call
+#  undef lua_call
+#  define lua_call(L, na, nr) \
+  (lua_callk)(L, na, nr, 0, NULL)
+#endif
+
+#ifdef lua_pcall
+#  undef lua_pcall
+#  define lua_pcall(L, na, nr, err) \
+  (lua_pcallk)(L, na, nr, err, 0, NULL)
+#endif
+
+#ifdef lua_yield
+#  undef lua_yield
+#  define lua_yield(L, nr) \
+  (lua_yieldk)(L, nr, 0, NULL)
+#endif
+
+#endif /* Lua 5.2 only */
+
+
+
+/* other Lua versions */
+#if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 501 || LUA_VERSION_NUM > 503
+
+#  error "unsupported Lua version (i.e. not Lua 5.1, 5.2, or 5.3)"
+
+#endif /* other Lua versions except 5.1, 5.2, and 5.3 */
+
+
+
+/* helper macro for defining continuation functions (for every version
+ * *except* Lua 5.2) */
+#ifndef LUA_KFUNCTION
+#define LUA_KFUNCTION(_name) \
+  static int (_name)(lua_State *L, int status, lua_KContext ctx)
+#endif
+
+
+#if defined(COMPAT53_INCLUDE_SOURCE)
+#  include "compat-5.3.c"
+#endif
+
+
+#endif /* COMPAT53_H_ */
+
diff --git a/tests/test.lua b/tests/test.lua
new file mode 100755
index 0000000..cc07ee8
--- /dev/null
+++ b/tests/test.lua
@@ -0,0 +1,109 @@
+#!/usr/bin/env lua
+
+local mod = require( "testmod" )
+local F
+do
+  local type, unpack = type, table.unpack or unpack
+  function F( ... )
+    local args, n = { ... }, select( '#', ... )
+    for i = 1, n do
+      local t = type( args[ i ] )
+      if t ~= "string" and t ~= "number" and t ~= "boolean" then
+        args[ i ] = t
+      end
+    end
+    return unpack( args, 1, n )
+  end
+end
+
+
+print( mod.isinteger( 1 ) )
+print( mod.isinteger( 0 ) )
+print( mod.isinteger( 1234567 ) )
+print( mod.isinteger( 12.3 ) )
+print( mod.isinteger( math.huge ) )
+print( mod.isinteger( math.sqrt( -1 ) ) )
+
+
+print( mod.rotate( 1, 1, 2, 3, 4, 5, 6 ) )
+print( mod.rotate(-1, 1, 2, 3, 4, 5, 6 ) )
+print( mod.rotate( 4, 1, 2, 3, 4, 5, 6 ) )
+print( mod.rotate( -4, 1, 2, 3, 4, 5, 6 ) )
+
+
+print( mod.strtonum( "+123" ) )
+print( mod.strtonum( " 123 " ) )
+print( mod.strtonum( "-1.23" ) )
+print( mod.strtonum( " 123 abc" ) )
+print( mod.strtonum( "jkl" ) )
+
+
+local a, b, c = mod.requiref()
+print( type( a ), type( b ), type( c ),
+       a.boolean, b.boolean, c.boolean,
+       type( requiref1 ), type( requiref2 ), type( requiref3 ) )
+
+local proxy, backend = {}, {}
+setmetatable( proxy, { __index = backend, __newindex = backend } )
+print( rawget( proxy, 1 ), rawget( backend, 1 ) )
+print( mod.getseti( proxy, 1 ) )
+print( rawget( proxy, 1 ), rawget( backend, 1 ) )
+print( mod.getseti( proxy, 1 ) )
+print( rawget( proxy, 1 ), rawget( backend, 1 ) )
+
+-- tests for Lua 5.1
+print(mod.tonumber(12))
+print(mod.tonumber("12"))
+print(mod.tonumber("0"))
+print(mod.tonumber(false))
+print(mod.tonumber("error"))
+
+print(mod.tointeger(12))
+print(mod.tointeger("12"))
+print(mod.tointeger("0"))
+print( "aaa" )
+print(mod.tointeger(math.pi))
+print( "bbb" )
+print(mod.tointeger(false))
+print(mod.tointeger("error"))
+
+print(mod.len("123"))
+print(mod.len({ 1, 2, 3}))
+print(pcall(mod.len, true))
+local ud, meta = mod.newproxy()
+meta.__len = function() return 5 end
+print(mod.len(ud))
+meta.__len = function() return true end
+print(pcall(mod.len, ud))
+
+print(mod.copy(true, "string", {}, 1))
+
+print(mod.rawxetp())
+print(mod.rawxetp("I'm back"))
+
+print(F(mod.globals()), mod.globals() == _G)
+
+local t = {}
+print(F(mod.subtable(t)))
+local x, msg = mod.subtable(t)
+print(F(x, msg, x == t.xxx))
+
+print(F(mod.udata()))
+print(mod.udata("nosuchtype"))
+
+print(F(mod.uservalue()))
+
+print(mod.getupvalues())
+
+print(mod.absindex("hi", true))
+
+print(mod.tolstring("string"))
+local t = setmetatable({}, {
+  __tostring = function(v) return "mytable" end
+})
+print(mod.tolstring( t ) )
+local t = setmetatable({}, {
+  __tostring = function(v) return nil end
+})
+print(pcall(mod.tolstring, t))
+
diff --git a/tests/testmod.c b/tests/testmod.c
new file mode 100644
index 0000000..a9c8e8d
--- /dev/null
+++ b/tests/testmod.c
@@ -0,0 +1,246 @@
+#include <stdio.h>
+#include <lua.h>
+#include <lauxlib.h>
+#include "compat-5.3.h"
+
+
+static int test_isinteger (lua_State *L) {
+  lua_pushboolean(L, lua_isinteger(L, 1));
+  return 1;
+}
+
+
+static int test_rotate (lua_State *L) {
+  int r = luaL_checkint(L, 1);
+  int n = lua_gettop(L)-1;
+  luaL_argcheck(L, (r < 0 ? -r : r) <= n, 1, "not enough arguments");
+  lua_rotate(L, 2, r);
+  return n;
+}
+
+
+static int test_str2num (lua_State *L) {
+  const char *s = luaL_checkstring(L, 1);
+  size_t len = lua_stringtonumber(L, s);
+  if (len == 0)
+    lua_pushnumber(L, 0);
+  lua_pushinteger(L, (lua_Integer)len);
+  return 2;
+}
+
+
+static int my_mod (lua_State *L ) {
+  lua_newtable(L);
+  lua_pushboolean(L, 1);
+  lua_setfield(L, -2, "boolean");
+  return 1;
+}
+
+static int test_requiref (lua_State *L) {
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_newtable(L);
+  lua_pushboolean(L, 0);
+  lua_setfield(L, -2, "boolean");
+  lua_setfield(L, -2, "requiref3");
+  lua_pop(L, 1);
+  luaL_requiref(L, "requiref1", my_mod, 0);
+  luaL_requiref(L, "requiref2", my_mod, 1);
+  luaL_requiref(L, "requiref3", my_mod, 1);
+  return 3;
+}
+
+static int test_getseti (lua_State *L) {
+  lua_Integer k = luaL_checkinteger(L, 2);
+  lua_Integer n = 0;
+  if (lua_geti(L, 1, k) == LUA_TNUMBER) {
+    n = lua_tointeger(L, -1);
+  } else {
+    lua_pop(L, 1);
+    lua_pushinteger(L, n);
+  }
+  lua_pushinteger(L, n+1);
+  lua_seti(L, 1, k);
+  return 1;
+}
+
+
+/* additional tests for Lua5.1 */
+#define NUP 3
+
+static int test_newproxy (lua_State *L) {
+  lua_settop(L, 0);
+  lua_newuserdata(L, 0);
+  lua_newtable(L);
+  lua_pushvalue(L, -1);
+  lua_pushboolean(L, 1);
+  lua_setfield(L, -2, "__gc");
+  lua_setmetatable(L, -3);
+  return 2;
+}
+
+static int test_absindex (lua_State *L) {
+  int i = 1;
+  for (i = 1; i <= NUP; ++i)
+    lua_pushvalue(L, lua_absindex(L, lua_upvalueindex(i)));
+  lua_pushvalue(L, lua_absindex(L, LUA_REGISTRYINDEX));
+  lua_pushstring(L, lua_typename(L, lua_type(L, lua_absindex(L, -1))));
+  lua_replace(L, lua_absindex(L, -2));
+  lua_pushvalue(L, lua_absindex(L, -2));
+  lua_pushvalue(L, lua_absindex(L, -4));
+  lua_pushvalue(L, lua_absindex(L, -6));
+  i += 3;
+  lua_pushvalue(L, lua_absindex(L, 1));
+  lua_pushvalue(L, lua_absindex(L, 2));
+  lua_pushvalue(L, lua_absindex(L, 3));
+  i += 3;
+  return i;
+}
+
+static int test_globals (lua_State *L) {
+  lua_pushglobaltable(L);
+  return 1;
+}
+
+static int test_tonumber (lua_State *L) {
+  int isnum = 0;
+  lua_Number n = lua_tonumberx(L, 1, &isnum);
+  if (!isnum)
+    lua_pushnil(L);
+  else
+    lua_pushnumber(L, n);
+  return 1;
+}
+
+static int test_tointeger (lua_State *L) {
+  int isnum = 0;
+  lua_Integer n = lua_tointegerx(L, 1, &isnum);
+  if (!isnum)
+    lua_pushnil(L);
+  else
+    lua_pushinteger(L, n);
+  return 1;
+}
+
+static int test_len (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_len(L, 1);
+  lua_pushinteger(L, luaL_len(L, 1));
+  return 2;
+}
+
+static int test_copy (lua_State *L) {
+  int args = lua_gettop(L);
+  if (args >= 2) {
+    int i = 0;
+    for (i = args-1; i > 0; --i)
+      lua_copy(L, args, i);
+  }
+  return args;
+}
+
+/* need an address */
+static char const dummy = 0;
+
+static int test_rawxetp (lua_State *L) {
+  if (lua_gettop(L) > 0)
+    lua_pushvalue(L, 1);
+  else
+    lua_pushliteral(L, "hello again");
+  lua_rawsetp(L, LUA_REGISTRYINDEX, &dummy);
+  lua_settop(L, 0);
+  lua_rawgetp(L, LUA_REGISTRYINDEX, &dummy);
+  return 1;
+}
+
+static int test_udata (lua_State *L) {
+  const char *tname = luaL_optstring(L, 1, "utype1");
+  void *u1 = lua_newuserdata(L, 1);
+  int u1pos = lua_gettop(L);
+  void *u2 = lua_newuserdata(L, 1);
+  int u2pos = lua_gettop(L);
+  luaL_newmetatable(L, "utype1");
+  luaL_newmetatable(L, "utype2");
+  lua_pop(L, 2);
+  luaL_setmetatable(L, "utype2");
+  lua_pushvalue(L, u1pos);
+  luaL_setmetatable(L, "utype1");
+  lua_pop(L, 1);
+  (void)u1;
+  (void)u2;
+  lua_pushlightuserdata(L, luaL_testudata(L, u1pos, tname));
+  lua_pushlightuserdata(L, luaL_testudata(L, u2pos, tname));
+  return 2;
+}
+
+static int test_subtable (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_settop(L, 1);
+  if (luaL_getsubtable(L, 1, "xxx")) {
+    lua_pushliteral(L, "oldtable");
+  } else {
+    lua_pushliteral(L, "newtable");
+  }
+  return 2;
+}
+
+static int test_uservalue (lua_State *L) {
+  void *udata = lua_newuserdata(L, 1);
+  int ui = lua_gettop(L);
+  lua_newtable(L);
+  lua_setuservalue(L, ui);
+  lua_getuservalue(L, ui);
+  (void)udata;
+  return 1;
+}
+
+static int test_upvalues (lua_State *L) {
+  int i = 1;
+  for (i = 1; i <= NUP; ++i)
+    lua_pushvalue(L, lua_upvalueindex(i));
+  return NUP;
+}
+
+static int test_tolstring (lua_State *L) {
+  size_t len = 0;
+  luaL_tolstring(L, 1, &len);
+  lua_pushinteger(L, (int)len);
+  return 2;
+}
+
+
+static const luaL_Reg funcs[] = {
+  { "isinteger", test_isinteger },
+  { "rotate", test_rotate },
+  { "strtonum", test_str2num },
+  { "requiref", test_requiref },
+  { "getseti", test_getseti },
+  { "newproxy", test_newproxy },
+  { "tonumber", test_tonumber },
+  { "tointeger", test_tointeger },
+  { "len", test_len },
+  { "copy", test_copy },
+  { "rawxetp", test_rawxetp },
+  { "subtable", test_subtable },
+  { "udata", test_udata },
+  { "uservalue", test_uservalue },
+  { "globals", test_globals },
+  { "tolstring", test_tolstring },
+  { NULL, NULL }
+};
+
+static const luaL_Reg more_funcs[] = {
+  { "getupvalues", test_upvalues },
+  { "absindex", test_absindex },
+  { NULL, NULL }
+};
+
+
+int luaopen_testmod (lua_State *L) {
+  int i = 1;
+  luaL_newlib(L, funcs);
+  for (i = 1; i <= NUP; ++i)
+    lua_pushnumber(L, i);
+  luaL_setfuncs(L, more_funcs, NUP);
+  return 1;
+}
+