- Implemented support for internal Lua scripts.

- Implemented %pretrans and %posttrans script slots.
Changed files:
	Makefile.am configure.ac build/pack.c build/parseScript.c
	build/parseSpec.c build/rpmbuild.h build/rpmspec.h
	lib/Makefile.am lib/psm.c lib/rpmlib.h lib/rpmlibprov.c
	lib/rpmts.c lib/rpmts.h lib/transaction.c
Added files:
	lib/rpmlua.c lib/rpmlua.h lua/*

CVS patchset: 7175
CVS date: 2004/03/16 21:58:25

10 files changed, 3821 insertions, 0 deletions

diff --git a/lua/lib/Makefile b/lua/lib/Makefile
new file mode 100644
index 000000000..7da14dc49
--- /dev/null
+++ b/lua/lib/Makefile
@@ -0,0 +1,28 @@
+# makefile for Lua standard library
+
+LUA= ../..
+
+include $(LUA)/config
+
+# actually only used in liolib.c
+EXTRA_DEFS= $(POPEN)
+
+OBJS= lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o ltablib.o lstrlib.o
+SRCS= lauxlib.c lbaselib.c ldblib.c liolib.c lmathlib.c ltablib.c lstrlib.c
+
+T= $(LIB)/liblualib.a
+
+all:	$T
+
+$T:	$(OBJS)
+	$(AR) $@ $(OBJS)
+	$(RANLIB) $@
+
+clean:
+	rm -f $(OBJS) $T
+
+co:
+	co -q -f -M $(SRCS)
+
+klean:	clean
+	rm -f $(SRCS)
diff --git a/lua/lib/README b/lua/lib/README
new file mode 100644
index 000000000..c5600b8ec
--- /dev/null
+++ b/lua/lib/README
@@ -0,0 +1,8 @@
+This is the standard Lua library.
+
+The code of the standard library can be read as an example of how to export
+C functions to Lua. The easiest library to read is lmathlib.c.
+
+The library is implemented entirely on top of the official Lua API as declared
+in lua.h, using lauxlib.c, which contains several useful functions for writing
+libraries. We encourage developers to use lauxlib.c in their own libraries.
diff --git a/lua/lib/lauxlib.c b/lua/lib/lauxlib.c
new file mode 100644
index 000000000..2655c3310
--- /dev/null
+++ b/lua/lib/lauxlib.c
@@ -0,0 +1,591 @@
+/*
+** $Id: lauxlib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+
+/* This file uses only the official API of Lua.
+** Any function declared here could be written as an application function.
+*/
+
+#define lauxlib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+
+
+/* number of prereserved references (for internal use) */
+#define RESERVED_REFS	2
+
+/* reserved references */
+#define FREELIST_REF	1	/* free list of references */
+#define ARRAYSIZE_REF	2	/* array sizes */
+
+
+/* convert a stack index to positive */
+#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
+					lua_gettop(L) + (i) + 1)
+
+
+/*
+** {======================================================
+** Error-report functions
+** =======================================================
+*/
+
+
+LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
+  lua_Debug ar;
+  lua_getstack(L, 0, &ar);
+  lua_getinfo(L, "n", &ar);
+  if (strcmp(ar.namewhat, "method") == 0) {
+    narg--;  /* do not count `self' */
+    if (narg == 0)  /* error is in the self argument itself? */
+      return luaL_error(L, "calling `%s' on bad self (%s)", ar.name, extramsg);
+  }
+  if (ar.name == NULL)
+    ar.name = "?";
+  return luaL_error(L, "bad argument #%d to `%s' (%s)",
+                        narg, ar.name, extramsg);
+}
+
+
+LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
+  const char *msg = lua_pushfstring(L, "%s expected, got %s",
+                                    tname, lua_typename(L, lua_type(L,narg)));
+  return luaL_argerror(L, narg, msg);
+}
+
+
+static void tag_error (lua_State *L, int narg, int tag) {
+  luaL_typerror(L, narg, lua_typename(L, tag)); 
+}
+
+
+LUALIB_API void luaL_where (lua_State *L, int level) {
+  lua_Debug ar;
+  if (lua_getstack(L, level, &ar)) {  /* check function at level */
+    lua_getinfo(L, "Snl", &ar);  /* get info about it */
+    if (ar.currentline > 0) {  /* is there info? */
+      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
+      return;
+    }
+  }
+  lua_pushliteral(L, "");  /* else, no information available... */
+}
+
+
+LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  luaL_where(L, 1);
+  lua_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_concat(L, 2);
+  return lua_error(L);
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_findstring (const char *name, const char *const list[]) {
+  int i;
+  for (i=0; list[i]; i++)
+    if (strcmp(list[i], name) == 0)
+      return i;
+  return -1;  /* name not found */
+}
+
+
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+  lua_pushstring(L, tname);
+  lua_rawget(L, LUA_REGISTRYINDEX);  /* get registry.name */
+  if (!lua_isnil(L, -1))  /* name already in use? */
+    return 0;  /* leave previous value on top, but return 0 */
+  lua_pop(L, 1);
+  lua_newtable(L);  /* create metatable */
+  lua_pushstring(L, tname);
+  lua_pushvalue(L, -2);
+  lua_rawset(L, LUA_REGISTRYINDEX);  /* registry.name = metatable */
+  lua_pushvalue(L, -1);
+  lua_pushstring(L, tname);
+  lua_rawset(L, LUA_REGISTRYINDEX);  /* registry[metatable] = name */
+  return 1;
+}
+
+
+LUALIB_API void  luaL_getmetatable (lua_State *L, const char *tname) {
+  lua_pushstring(L, tname);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  const char *tn;
+  if (!lua_getmetatable(L, ud)) return NULL;  /* no metatable? */
+  lua_rawget(L, LUA_REGISTRYINDEX);  /* get registry[metatable] */
+  tn = lua_tostring(L, -1);
+  if (tn && (strcmp(tn, tname) == 0)) {
+    lua_pop(L, 1);
+    return lua_touserdata(L, ud);
+  }
+  else {
+    lua_pop(L, 1);
+    return NULL;
+  }
+}
+
+
+LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
+  if (!lua_checkstack(L, space))
+    luaL_error(L, "stack overflow (%s)", mes);
+}
+
+
+LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
+  if (lua_type(L, narg) != t)
+    tag_error(L, narg, t);
+}
+
+
+LUALIB_API void luaL_checkany (lua_State *L, int narg) {
+  if (lua_type(L, narg) == LUA_TNONE)
+    luaL_argerror(L, narg, "value expected");
+}
+
+
+LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
+  const char *s = lua_tostring(L, narg);
+  if (!s) tag_error(L, narg, LUA_TSTRING);
+  if (len) *len = lua_strlen(L, narg);
+  return s;
+}
+
+
+LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
+                                        const char *def, size_t *len) {
+  if (lua_isnoneornil(L, narg)) {
+    if (len)
+      *len = (def ? strlen(def) : 0);
+    return def;
+  }
+  else return luaL_checklstring(L, narg, len);
+}
+
+
+LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
+  lua_Number d = lua_tonumber(L, narg);
+  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
+  if (lua_isnoneornil(L, narg)) return def;
+  else return luaL_checknumber(L, narg);
+}
+
+
+LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
+  if (!lua_getmetatable(L, obj))  /* no metatable? */
+    return 0;
+  lua_pushstring(L, event);
+  lua_rawget(L, -2);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 2);  /* remove metatable and metafield */
+    return 0;
+  }
+  else {
+    lua_remove(L, -2);  /* remove only metatable */
+    return 1;
+  }
+}
+
+
+LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
+  obj = abs_index(L, obj);
+  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
+    return 0;
+  lua_pushvalue(L, obj);
+  lua_call(L, 1, 1);
+  return 1;
+}
+
+
+LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
+                              const luaL_reg *l, int nup) {
+  if (libname) {
+    lua_pushstring(L, libname);
+    lua_gettable(L, LUA_GLOBALSINDEX);  /* check whether lib already exists */
+    if (lua_isnil(L, -1)) {  /* no? */
+      lua_pop(L, 1);
+      lua_newtable(L);  /* create it */
+      lua_pushstring(L, libname);
+      lua_pushvalue(L, -2);
+      lua_settable(L, LUA_GLOBALSINDEX);  /* register it with given name */
+    }
+    lua_insert(L, -(nup+1));  /* move library table to below upvalues */
+  }
+  for (; l->name; l++) {
+    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);
+    lua_settable(L, -(nup+3));
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+
+/*
+** {======================================================
+** getn-setn: size for arrays
+** =======================================================
+*/
+
+static int checkint (lua_State *L, int topop) {
+  int n = (int)lua_tonumber(L, -1);
+  if (n == 0 && !lua_isnumber(L, -1)) n = -1;
+  lua_pop(L, topop);
+  return n;
+}
+
+
+static void getsizes (lua_State *L) {
+  lua_rawgeti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF);
+  if (lua_isnil(L, -1)) {  /* no `size' table? */
+    lua_pop(L, 1);  /* remove nil */
+    lua_newtable(L);  /* create it */
+    lua_pushvalue(L, -1);  /* `size' will be its own metatable */
+    lua_setmetatable(L, -2);
+    lua_pushliteral(L, "__mode");
+    lua_pushliteral(L, "k");
+    lua_rawset(L, -3);  /* metatable(N).__mode = "k" */
+    lua_pushvalue(L, -1);
+    lua_rawseti(L, LUA_REGISTRYINDEX, ARRAYSIZE_REF);  /* store in register */
+  }
+}
+
+
+void luaL_setn (lua_State *L, int t, int n) {
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");
+  lua_rawget(L, t);
+  if (checkint(L, 1) >= 0) {  /* is there a numeric field `n'? */
+    lua_pushliteral(L, "n");  /* use it */
+    lua_pushnumber(L, (lua_Number)n);
+    lua_rawset(L, t);
+  }
+  else {  /* use `sizes' */
+    getsizes(L);
+    lua_pushvalue(L, t);
+    lua_pushnumber(L, (lua_Number)n);
+    lua_rawset(L, -3);  /* sizes[t] = n */
+    lua_pop(L, 1);  /* remove `sizes' */
+  }
+}
+
+
+int luaL_getn (lua_State *L, int t) {
+  int n;
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");  /* try t.n */
+  lua_rawget(L, t);
+  if ((n = checkint(L, 1)) >= 0) return n;
+  getsizes(L);  /* else try sizes[t] */
+  lua_pushvalue(L, t);
+  lua_rawget(L, -2);
+  if ((n = checkint(L, 2)) >= 0) return n;
+  for (n = 1; ; n++) {  /* else must count elements */
+    lua_rawgeti(L, t, n);
+    if (lua_isnil(L, -1)) break;
+    lua_pop(L, 1);
+  }
+  lua_pop(L, 1);
+  return n - 1;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+
+#define bufflen(B)	((B)->p - (B)->buffer)
+#define bufffree(B)	((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
+
+#define LIMIT	(LUA_MINSTACK/2)
+
+
+static int emptybuffer (luaL_Buffer *B) {
+  size_t l = bufflen(B);
+  if (l == 0) return 0;  /* put nothing on stack */
+  else {
+    lua_pushlstring(B->L, B->buffer, l);
+    B->p = B->buffer;
+    B->lvl++;
+    return 1;
+  }
+}
+
+
+static void adjuststack (luaL_Buffer *B) {
+  if (B->lvl > 1) {
+    lua_State *L = B->L;
+    int toget = 1;  /* number of levels to concat */
+    size_t toplen = lua_strlen(L, -1);
+    do {
+      size_t l = lua_strlen(L, -(toget+1));
+      if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
+        toplen += l;
+        toget++;
+      }
+      else break;
+    } while (toget < B->lvl);
+    lua_concat(L, toget);
+    B->lvl = B->lvl - toget + 1;
+  }
+}
+
+
+LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
+  if (emptybuffer(B))
+    adjuststack(B);
+  return B->buffer;
+}
+
+
+LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
+  while (l--)
+    luaL_putchar(B, *s++);
+}
+
+
+LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
+  luaL_addlstring(B, s, strlen(s));
+}
+
+
+LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
+  emptybuffer(B);
+  lua_concat(B->L, B->lvl);
+  B->lvl = 1;
+}
+
+
+LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
+  lua_State *L = B->L;
+  size_t vl = lua_strlen(L, -1);
+  if (vl <= bufffree(B)) {  /* fit into buffer? */
+    memcpy(B->p, lua_tostring(L, -1), vl);  /* put it there */
+    B->p += vl;
+    lua_pop(L, 1);  /* remove from stack */
+  }
+  else {
+    if (emptybuffer(B))
+      lua_insert(L, -2);  /* put buffer before new value */
+    B->lvl++;  /* add new value into B stack */
+    adjuststack(B);
+  }
+}
+
+
+LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
+  B->L = L;
+  B->p = B->buffer;
+  B->lvl = 0;
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_ref (lua_State *L, int t) {
+  int ref;
+  t = abs_index(L, t);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* remove from stack */
+    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
+  }
+  lua_rawgeti(L, t, FREELIST_REF);  /* get first free element */
+  ref = (int)lua_tonumber(L, -1);  /* ref = t[FREELIST_REF] */
+  lua_pop(L, 1);  /* remove it from stack */
+  if (ref != 0) {  /* any free element? */
+    lua_rawgeti(L, t, ref);  /* remove it from list */
+    lua_rawseti(L, t, FREELIST_REF);  /* (t[FREELIST_REF] = t[ref]) */
+  }
+  else {  /* no free elements */
+    ref = luaL_getn(L, t);
+    if (ref < RESERVED_REFS)
+      ref = RESERVED_REFS;  /* skip reserved references */
+    ref++;  /* create new reference */
+    luaL_setn(L, t, ref);
+  }
+  lua_rawseti(L, t, ref);
+  return ref;
+}
+
+
+LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
+  if (ref >= 0) {
+    t = abs_index(L, t);
+    lua_rawgeti(L, t, FREELIST_REF);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[FREELIST_REF] */
+    lua_pushnumber(L, (lua_Number)ref);
+    lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
+  }
+}
+
+
+
+/*
+** {======================================================
+** Load functions
+** =======================================================
+*/
+
+typedef struct LoadF {
+  FILE *f;
+  char buff[LUAL_BUFFERSIZE];
+} LoadF;
+
+
+static const char *getF (lua_State *L, void *ud, size_t *size) {
+  LoadF *lf = (LoadF *)ud;
+  (void)L;
+  if (feof(lf->f)) return NULL;
+  *size = fread(lf->buff, 1, LUAL_BUFFERSIZE, lf->f);
+  return (*size > 0) ? lf->buff : NULL;
+}
+
+
+static int errfile (lua_State *L, int fnameindex) {
+  const char *filename = lua_tostring(L, fnameindex) + 1;
+  lua_pushfstring(L, "cannot read %s: %s", filename, strerror(errno));
+  lua_remove(L, fnameindex);
+  return LUA_ERRFILE;
+}
+
+
+LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
+  LoadF lf;
+  int status, readstatus;
+  int c;
+  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
+  if (filename == NULL) {
+    lua_pushliteral(L, "=stdin");
+    lf.f = stdin;
+  }
+  else {
+    lua_pushfstring(L, "@%s", filename);
+    lf.f = fopen(filename, "r");
+  }
+  if (lf.f == NULL) return errfile(L, fnameindex);  /* unable to open file */
+  c = ungetc(getc(lf.f), lf.f);
+  if (!(isspace(c) || isprint(c)) && lf.f != stdin) {  /* binary file? */
+    fclose(lf.f);
+    lf.f = fopen(filename, "rb");  /* reopen in binary mode */
+    if (lf.f == NULL) return errfile(L, fnameindex); /* unable to reopen file */
+  }
+  status = lua_load(L, getF, &lf, lua_tostring(L, -1));
+  readstatus = ferror(lf.f);
+  if (lf.f != stdin) fclose(lf.f);  /* close file (even in case of errors) */
+  if (readstatus) {
+    lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
+    return errfile(L, fnameindex);
+  }
+  lua_remove(L, fnameindex);
+  return status;
+}
+
+
+typedef struct LoadS {
+  const char *s;
+  size_t size;
+} LoadS;
+
+
+static const char *getS (lua_State *L, void *ud, size_t *size) {
+  LoadS *ls = (LoadS *)ud;
+  (void)L;
+  if (ls->size == 0) return NULL;
+  *size = ls->size;
+  ls->size = 0;
+  return ls->s;
+}
+
+
+LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
+                                const char *name) {
+  LoadS ls;
+  ls.s = buff;
+  ls.size = size;
+  return lua_load(L, getS, &ls, name);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** compatibility code
+** =======================================================
+*/
+
+
+static void callalert (lua_State *L, int status) {
+  if (status != 0) {
+    lua_getglobal(L, "_ALERT");
+    if (lua_isfunction(L, -1)) {
+      lua_insert(L, -2);
+      lua_call(L, 1, 0);
+    }
+    else {  /* no _ALERT function; print it on stderr */
+      fprintf(stderr, "%s\n", lua_tostring(L, -2));
+      lua_pop(L, 2);  /* remove error message and _ALERT */
+    }
+  }
+}
+
+
+static int aux_do (lua_State *L, int status) {
+  if (status == 0) {  /* parse OK? */
+    status = lua_pcall(L, 0, LUA_MULTRET, 0);  /* call main */
+  }
+  callalert(L, status);
+  return status;
+}
+
+
+LUALIB_API int lua_dofile (lua_State *L, const char *filename) {
+  return aux_do(L, luaL_loadfile(L, filename));
+}
+
+
+LUALIB_API int lua_dobuffer (lua_State *L, const char *buff, size_t size,
+                          const char *name) {
+  return aux_do(L, luaL_loadbuffer(L, buff, size, name));
+}
+
+
+LUALIB_API int lua_dostring (lua_State *L, const char *str) {
+  return lua_dobuffer(L, str, strlen(str), str);
+}
+
+/* }====================================================== */
diff --git a/lua/lib/lbaselib.c b/lua/lib/lbaselib.c
new file mode 100644
index 000000000..72114c083
--- /dev/null
+++ b/lua/lib/lbaselib.c
@@ -0,0 +1,674 @@
+/*
+** $Id: lbaselib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Basic library
+** See Copyright Notice in lua.h
+*/
+
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lbaselib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+
+/*
+** If your system does not support `stdout', you can just remove this function.
+** If you need, you can define your own `print' function, following this
+** model but changing `fputs' to put the strings at a proper place
+** (a console window or a log file, for instance).
+*/
+static int luaB_print (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  lua_getglobal(L, "tostring");
+  for (i=1; i<=n; i++) {
+    const char *s;
+    lua_pushvalue(L, -1);  /* function to be called */
+    lua_pushvalue(L, i);   /* value to print */
+    lua_call(L, 1, 1);
+    s = lua_tostring(L, -1);  /* get result */
+    if (s == NULL)
+      return luaL_error(L, "`tostring' must return a string to `print'");
+    if (i>1) fputs("\t", stdout);
+    fputs(s, stdout);
+    lua_pop(L, 1);  /* pop result */
+  }
+  fputs("\n", stdout);
+  return 0;
+}
+
+
+static int luaB_tonumber (lua_State *L) {
+  int base = luaL_optint(L, 2, 10);
+  if (base == 10) {  /* standard conversion */
+    luaL_checkany(L, 1);
+    if (lua_isnumber(L, 1)) {
+      lua_pushnumber(L, lua_tonumber(L, 1));
+      return 1;
+    }
+  }
+  else {
+    const char *s1 = luaL_checkstring(L, 1);
+    char *s2;
+    unsigned long n;
+    luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
+    n = strtoul(s1, &s2, base);
+    if (s1 != s2) {  /* at least one valid digit? */
+      while (isspace((unsigned char)(*s2))) s2++;  /* skip trailing spaces */
+      if (*s2 == '\0') {  /* no invalid trailing characters? */
+        lua_pushnumber(L, (lua_Number)n);
+        return 1;
+      }
+    }
+  }
+  lua_pushnil(L);  /* else not a number */
+  return 1;
+}
+
+
+static int luaB_error (lua_State *L) {
+  int level = luaL_optint(L, 2, 1);
+  luaL_checkany(L, 1);
+  if (!lua_isstring(L, 1) || level == 0)
+    lua_pushvalue(L, 1);  /* propagate error message without changes */
+  else {  /* add extra information */
+    luaL_where(L, level);
+    lua_pushvalue(L, 1);
+    lua_concat(L, 2);
+  }
+  return lua_error(L);
+}
+
+
+static int luaB_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);
+    return 1;  /* no metatable */
+  }
+  luaL_getmetafield(L, 1, "__metatable");
+  return 1;  /* returns either __metatable field (if present) or metatable */
+}
+
+
+static int luaB_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
+                    "nil or table expected");
+  if (luaL_getmetafield(L, 1, "__metatable"))
+    luaL_error(L, "cannot change a protected metatable");
+  lua_settop(L, 2);
+  lua_setmetatable(L, 1);
+  return 1;
+}
+
+
+static void getfunc (lua_State *L) {
+  if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
+  else {
+    lua_Debug ar;
+    int level = luaL_optint(L, 1, 1);
+    luaL_argcheck(L, level >= 0, 1, "level must be non-negative");
+    if (lua_getstack(L, level, &ar) == 0)
+      luaL_argerror(L, 1, "invalid level");
+    lua_getinfo(L, "f", &ar);
+    if (lua_isnil(L, -1))
+      luaL_error(L, "no function environment for tail call at level %d",
+                    level);
+  }
+}
+
+
+static int aux_getfenv (lua_State *L) {
+  lua_getfenv(L, -1);
+  lua_pushliteral(L, "__fenv");
+  lua_rawget(L, -2);
+  return !lua_isnil(L, -1);
+}
+
+
+static int luaB_getfenv (lua_State *L) {
+  getfunc(L);
+  if (!aux_getfenv(L))  /* __fenv not defined? */
+    lua_pop(L, 1);  /* remove it, to return real environment */
+  return 1;
+}
+
+
+static int luaB_setfenv (lua_State *L) {
+  luaL_checktype(L, 2, LUA_TTABLE);
+  getfunc(L);
+  if (aux_getfenv(L))  /* __fenv defined? */
+    luaL_error(L, "`setfenv' cannot change a protected environment");
+  else
+    lua_pop(L, 2);  /* remove __fenv and real environment table */
+  lua_pushvalue(L, 2);
+  if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0)
+    lua_replace(L, LUA_GLOBALSINDEX);
+  else if (lua_setfenv(L, -2) == 0)
+    luaL_error(L, "`setfenv' cannot change environment of given function");
+  return 0;
+}
+
+
+static int luaB_rawequal (lua_State *L) {
+  luaL_checkany(L, 1);
+  luaL_checkany(L, 2);
+  lua_pushboolean(L, lua_rawequal(L, 1, 2));
+  return 1;
+}
+
+
+static int luaB_rawget (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  lua_rawget(L, 1);
+  return 1;
+}
+
+static int luaB_rawset (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  luaL_checkany(L, 3);
+  lua_rawset(L, 1);
+  return 1;
+}
+
+
+static int luaB_gcinfo (lua_State *L) {
+  lua_pushnumber(L, (lua_Number)lua_getgccount(L));
+  lua_pushnumber(L, (lua_Number)lua_getgcthreshold(L));
+  return 2;
+}
+
+
+static int luaB_collectgarbage (lua_State *L) {
+  lua_setgcthreshold(L, luaL_optint(L, 1, 0));
+  return 0;
+}
+
+
+static int luaB_type (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_pushstring(L, lua_typename(L, lua_type(L, 1)));
+  return 1;
+}
+
+
+static int luaB_next (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_settop(L, 2);  /* create a 2nd argument if there isn't one */
+  if (lua_next(L, 1))
+    return 2;
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int luaB_pairs (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushliteral(L, "next");
+  lua_rawget(L, LUA_GLOBALSINDEX);  /* return generator, */
+  lua_pushvalue(L, 1);  /* state, */
+  lua_pushnil(L);  /* and initial value */
+  return 3;
+}
+
+
+static int luaB_ipairs (lua_State *L) {
+  lua_Number i = lua_tonumber(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  if (i == 0 && lua_isnone(L, 2)) {  /* `for' start? */
+    lua_pushliteral(L, "ipairs");
+    lua_rawget(L, LUA_GLOBALSINDEX);  /* return generator, */
+    lua_pushvalue(L, 1);  /* state, */
+    lua_pushnumber(L, 0);  /* and initial value */
+    return 3;
+  }
+  else {  /* `for' step */
+    i++;  /* next value */
+    lua_pushnumber(L, i);
+    lua_rawgeti(L, 1, (int)i);
+    return (lua_isnil(L, -1)) ? 0 : 2;
+  }
+}
+
+
+static int load_aux (lua_State *L, int status) {
+  if (status == 0)  /* OK? */
+    return 1;
+  else {
+    lua_pushnil(L);
+    lua_insert(L, -2);  /* put before error message */
+    return 2;  /* return nil plus error message */
+  }
+}
+
+
+static int luaB_loadstring (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  const char *chunkname = luaL_optstring(L, 2, s);
+  return load_aux(L, luaL_loadbuffer(L, s, l, chunkname));
+}
+
+
+static int luaB_loadfile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  return load_aux(L, luaL_loadfile(L, fname));
+}
+
+
+static int luaB_dofile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  int status = luaL_loadfile(L, fname);
+  if (status != 0) lua_error(L);
+  lua_call(L, 0, LUA_MULTRET);
+  return lua_gettop(L) - 1;
+}
+
+
+static int luaB_assert (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_toboolean(L, 1))
+    return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));
+  lua_settop(L, 1);
+  return 1;
+}
+
+
+static int luaB_unpack (lua_State *L) {
+  int n, i;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  n = luaL_getn(L, 1);
+  luaL_checkstack(L, n, "table too big to unpack");
+  for (i=1; i<=n; i++)  /* push arg[1...n] */
+    lua_rawgeti(L, 1, i);
+  return n;
+}
+
+
+static int luaB_pcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 1);
+  status = lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0);
+  lua_pushboolean(L, (status == 0));
+  lua_insert(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_xpcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_insert(L, 1);  /* put error function under function to be called */
+  status = lua_pcall(L, 0, LUA_MULTRET, 1);
+  lua_pushboolean(L, (status == 0));
+  lua_replace(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_tostring (lua_State *L) {
+  char buff[64];
+  luaL_checkany(L, 1);
+  if (luaL_callmeta(L, 1, "__tostring"))  /* is there a metafield? */
+    return 1;  /* use its value */
+  switch (lua_type(L, 1)) {
+    case LUA_TNUMBER:
+      lua_pushstring(L, lua_tostring(L, 1));
+      return 1;
+    case LUA_TSTRING:
+      lua_pushvalue(L, 1);
+      return 1;
+    case LUA_TBOOLEAN:
+      lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));
+      return 1;
+    case LUA_TTABLE:
+      sprintf(buff, "table: %p", lua_topointer(L, 1));
+      break;
+    case LUA_TFUNCTION:
+      sprintf(buff, "function: %p", lua_topointer(L, 1));
+      break;
+    case LUA_TUSERDATA:
+    case LUA_TLIGHTUSERDATA:
+      sprintf(buff, "userdata: %p", lua_touserdata(L, 1));
+      break;
+    case LUA_TTHREAD:
+      sprintf(buff, "thread: %p", (void *)lua_tothread(L, 1));
+      break;
+    case LUA_TNIL:
+      lua_pushliteral(L, "nil");
+      return 1;
+  }
+  lua_pushstring(L, buff);
+  return 1;
+}
+
+
+static int luaB_newproxy (lua_State *L) {
+  lua_settop(L, 1);
+  lua_newuserdata(L, 0);  /* create proxy */
+  if (lua_toboolean(L, 1) == 0)
+    return 1;  /* no metatable */
+  else if (lua_isboolean(L, 1)) {
+    lua_newtable(L);  /* create a new metatable `m' ... */
+    lua_pushvalue(L, -1);  /* ... and mark `m' as a valid metatable */
+    lua_pushboolean(L, 1);
+    lua_rawset(L, lua_upvalueindex(1));  /* weaktable[m] = true */
+  }
+  else {
+    int validproxy = 0;  /* to check if weaktable[metatable(u)] == true */
+    if (lua_getmetatable(L, 1)) {
+      lua_rawget(L, lua_upvalueindex(1));
+      validproxy = lua_toboolean(L, -1);
+      lua_pop(L, 1);  /* remove value */
+    }
+    luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");
+    lua_getmetatable(L, 1);  /* metatable is valid; get it */
+  }
+  lua_setmetatable(L, 2);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** `require' function
+** =======================================================
+*/
+
+
+/* name of global that holds table with loaded packages */
+#define REQTAB		"_LOADED"
+
+/* name of global that holds the search path for packages */
+#define LUA_PATH	"LUA_PATH"
+
+#ifndef LUA_PATH_SEP
+#define LUA_PATH_SEP	';'
+#endif
+
+#ifndef LUA_PATH_MARK
+#define LUA_PATH_MARK	'?'
+#endif
+
+#ifndef LUA_PATH_DEFAULT
+#define LUA_PATH_DEFAULT	"?;?.lua"
+#endif
+
+
+static const char *getpath (lua_State *L) {
+  const char *path;
+  lua_getglobal(L, LUA_PATH);  /* try global variable */
+  path = lua_tostring(L, -1);
+  lua_pop(L, 1);
+  if (path) return path;
+  path = getenv(LUA_PATH);  /* else try environment variable */
+  if (path) return path;
+  return LUA_PATH_DEFAULT;  /* else use default */
+}
+
+
+static const char *pushnextpath (lua_State *L, const char *path) {
+  const char *l;
+  if (*path == '\0') return NULL;  /* no more paths */
+  if (*path == LUA_PATH_SEP) path++;  /* skip separator */
+  l = strchr(path, LUA_PATH_SEP);  /* find next separator */
+  if (l == NULL) l = path+strlen(path);
+  lua_pushlstring(L, path, l - path);  /* directory name */
+  return l;
+}
+
+
+static void pushcomposename (lua_State *L) {
+  const char *path = lua_tostring(L, -1);
+  const char *wild;
+  int n = 1;
+  while ((wild = strchr(path, LUA_PATH_MARK)) != NULL) {
+    /* is there stack space for prefix, name, and eventual last sufix? */
+    luaL_checkstack(L, 3, "too many marks in a path component");
+    lua_pushlstring(L, path, wild - path);  /* push prefix */
+    lua_pushvalue(L, 1);  /* push package name (in place of MARK) */
+    path = wild + 1;  /* continue after MARK */
+    n += 2;
+  }
+  lua_pushstring(L, path);  /* push last sufix (`n' already includes this) */
+  lua_concat(L, n);
+}
+
+
+static int luaB_require (lua_State *L) {
+  const char *path;
+  int status = LUA_ERRFILE;  /* not found (yet) */
+  luaL_checkstring(L, 1);
+  lua_settop(L, 1);
+  lua_getglobal(L, REQTAB);
+  if (!lua_istable(L, 2)) return luaL_error(L, "`" REQTAB "' is not a table");
+  path = getpath(L);
+  lua_pushvalue(L, 1);  /* check package's name in book-keeping table */
+  lua_rawget(L, 2);
+  if (lua_toboolean(L, -1))  /* is it there? */
+    return 1;  /* package is already loaded; return its result */
+  else {  /* must load it */
+    while (status == LUA_ERRFILE) {
+      lua_settop(L, 3);  /* reset stack position */
+      if ((path = pushnextpath(L, path)) == NULL) break;
+      pushcomposename(L);
+      status = luaL_loadfile(L, lua_tostring(L, -1));  /* try to load it */
+    }
+  }
+  switch (status) {
+    case 0: {
+      lua_getglobal(L, "_REQUIREDNAME");  /* save previous name */
+      lua_insert(L, -2);  /* put it below function */
+      lua_pushvalue(L, 1);
+      lua_setglobal(L, "_REQUIREDNAME");  /* set new name */
+      lua_call(L, 0, 1);  /* run loaded module */
+      lua_insert(L, -2);  /* put result below previous name */
+      lua_setglobal(L, "_REQUIREDNAME");  /* reset to previous name */
+      if (lua_isnil(L, -1)) {  /* no/nil return? */
+        lua_pushboolean(L, 1);
+        lua_replace(L, -2);  /* replace to true */
+      }
+      lua_pushvalue(L, 1);
+      lua_pushvalue(L, -2);
+      lua_rawset(L, 2);  /* mark it as loaded */
+      return 1;  /* return value */
+    }
+    case LUA_ERRFILE: {  /* file not found */
+      return luaL_error(L, "could not load package `%s' from path `%s'",
+                            lua_tostring(L, 1), getpath(L));
+    }
+    default: {
+      return luaL_error(L, "error loading package `%s' (%s)",
+                           lua_tostring(L, 1), lua_tostring(L, -1));
+    }
+  }
+}
+
+/* }====================================================== */
+
+
+static const luaL_reg base_funcs[] = {
+  {"error", luaB_error},
+  {"getmetatable", luaB_getmetatable},
+  {"setmetatable", luaB_setmetatable},
+  {"getfenv", luaB_getfenv},
+  {"setfenv", luaB_setfenv},
+  {"next", luaB_next},
+  {"ipairs", luaB_ipairs},
+  {"pairs", luaB_pairs},
+  {"print", luaB_print},
+  {"tonumber", luaB_tonumber},
+  {"tostring", luaB_tostring},
+  {"type", luaB_type},
+  {"assert", luaB_assert},
+  {"unpack", luaB_unpack},
+  {"rawequal", luaB_rawequal},
+  {"rawget", luaB_rawget},
+  {"rawset", luaB_rawset},
+  {"pcall", luaB_pcall},
+  {"xpcall", luaB_xpcall},
+  {"collectgarbage", luaB_collectgarbage},
+  {"gcinfo", luaB_gcinfo},
+  {"loadfile", luaB_loadfile},
+  {"dofile", luaB_dofile},
+  {"loadstring", luaB_loadstring},
+  {"require", luaB_require},
+  {NULL, NULL}
+};
+
+
+/*
+** {======================================================
+** Coroutine library
+** =======================================================
+*/
+
+static int auxresume (lua_State *L, lua_State *co, int narg) {
+  int status;
+  if (!lua_checkstack(co, narg))
+    luaL_error(L, "too many arguments to resume");
+  lua_xmove(L, co, narg);
+  status = lua_resume(co, narg);
+  if (status == 0) {
+    int nres = lua_gettop(co);
+    if (!lua_checkstack(L, nres))
+      luaL_error(L, "too many results to resume");
+    lua_xmove(co, L, nres);  /* move yielded values */
+    return nres;
+  }
+  else {
+    lua_xmove(co, L, 1);  /* move error message */
+    return -1;  /* error flag */
+  }
+}
+
+
+static int luaB_coresume (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  int r;
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  r = auxresume(L, co, lua_gettop(L) - 1);
+  if (r < 0) {
+    lua_pushboolean(L, 0);
+    lua_insert(L, -2);
+    return 2;  /* return false + error message */
+  }
+  else {
+    lua_pushboolean(L, 1);
+    lua_insert(L, -(r + 1));
+    return r + 1;  /* return true + `resume' returns */
+  }
+}
+
+
+static int luaB_auxwrap (lua_State *L) {
+  lua_State *co = lua_tothread(L, lua_upvalueindex(1));
+  int r = auxresume(L, co, lua_gettop(L));
+  if (r < 0) {
+    if (lua_isstring(L, -1)) {  /* error object is a string? */
+      luaL_where(L, 1);  /* add extra info */
+      lua_insert(L, -2);
+      lua_concat(L, 2);
+    }
+    lua_error(L);  /* propagate error */
+  }
+  return r;
+}
+
+
+static int luaB_cocreate (lua_State *L) {
+  lua_State *NL = lua_newthread(L);
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
+    "Lua function expected");
+  lua_pushvalue(L, 1);  /* move function to top */
+  lua_xmove(L, NL, 1);  /* move function from L to NL */
+  return 1;
+}
+
+
+static int luaB_cowrap (lua_State *L) {
+  luaB_cocreate(L);
+  lua_pushcclosure(L, luaB_auxwrap, 1);
+  return 1;
+}
+
+
+static int luaB_yield (lua_State *L) {
+  return lua_yield(L, lua_gettop(L));
+}
+
+
+static int luaB_costatus (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  if (L == co) lua_pushliteral(L, "running");
+  else {
+    lua_Debug ar;
+    if (lua_getstack(co, 0, &ar) == 0 && lua_gettop(co) == 0)
+      lua_pushliteral(L, "dead");
+    else
+      lua_pushliteral(L, "suspended");
+  }
+  return 1;
+}
+
+
+static const luaL_reg co_funcs[] = {
+  {"create", luaB_cocreate},
+  {"wrap", luaB_cowrap},
+  {"resume", luaB_coresume},
+  {"yield", luaB_yield},
+  {"status", luaB_costatus},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+
+static void base_open (lua_State *L) {
+  lua_pushliteral(L, "_G");
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  luaL_openlib(L, NULL, base_funcs, 0);  /* open lib into global table */
+  lua_pushliteral(L, "_VERSION");
+  lua_pushliteral(L, LUA_VERSION);
+  lua_rawset(L, -3);  /* set global _VERSION */
+  /* `newproxy' needs a weaktable as upvalue */
+  lua_pushliteral(L, "newproxy");
+  lua_newtable(L);  /* new table `w' */
+  lua_pushvalue(L, -1);  /* `w' will be its own metatable */
+  lua_setmetatable(L, -2);
+  lua_pushliteral(L, "__mode");
+  lua_pushliteral(L, "k");
+  lua_rawset(L, -3);  /* metatable(w).__mode = "k" */
+  lua_pushcclosure(L, luaB_newproxy, 1);
+  lua_rawset(L, -3);  /* set global `newproxy' */
+  lua_rawset(L, -1);  /* set global _G */
+}
+
+
+LUALIB_API int luaopen_base (lua_State *L) {
+  base_open(L);
+  luaL_openlib(L, LUA_COLIBNAME, co_funcs, 0);
+  lua_newtable(L);
+  lua_setglobal(L, REQTAB);
+  return 0;
+}
+
diff --git a/lua/lib/ldblib.c b/lua/lib/ldblib.c
new file mode 100644
index 000000000..ca1ddfcad
--- /dev/null
+++ b/lua/lib/ldblib.c
@@ -0,0 +1,299 @@
+/*
+** $Id: ldblib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Interface from Lua to its debug API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldblib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+static void settabss (lua_State *L, const char *i, const char *v) {
+  lua_pushstring(L, i);
+  lua_pushstring(L, v);
+  lua_rawset(L, -3);
+}
+
+
+static void settabsi (lua_State *L, const char *i, int v) {
+  lua_pushstring(L, i);
+  lua_pushnumber(L, (lua_Number)v);
+  lua_rawset(L, -3);
+}
+
+
+static int getinfo (lua_State *L) {
+  lua_Debug ar;
+  const char *options = luaL_optstring(L, 2, "flnSu");
+  if (lua_isnumber(L, 1)) {
+    if (!lua_getstack(L, (int)(lua_tonumber(L, 1)), &ar)) {
+      lua_pushnil(L);  /* level out of range */
+      return 1;
+    }
+  }
+  else if (lua_isfunction(L, 1)) {
+    lua_pushfstring(L, ">%s", options);
+    options = lua_tostring(L, -1);
+    lua_pushvalue(L, 1);
+  }
+  else
+    return luaL_argerror(L, 1, "function or level expected");
+  if (!lua_getinfo(L, options, &ar))
+    return luaL_argerror(L, 2, "invalid option");
+  lua_newtable(L);
+  for (; *options; options++) {
+    switch (*options) {
+      case 'S':
+        settabss(L, "source", ar.source);
+        settabss(L, "short_src", ar.short_src);
+        settabsi(L, "linedefined", ar.linedefined);
+        settabss(L, "what", ar.what);
+        break;
+      case 'l':
+        settabsi(L, "currentline", ar.currentline);
+        break;
+      case 'u':
+        settabsi(L, "nups", ar.nups);
+        break;
+      case 'n':
+        settabss(L, "name", ar.name);
+        settabss(L, "namewhat", ar.namewhat);
+        break;
+      case 'f':
+        lua_pushliteral(L, "func");
+        lua_pushvalue(L, -3);
+        lua_rawset(L, -3);
+        break;
+    }
+  }
+  return 1;  /* return table */
+}
+    
+
+static int getlocal (lua_State *L) {
+  lua_Debug ar;
+  const char *name;
+  if (!lua_getstack(L, luaL_checkint(L, 1), &ar))  /* level out of range? */
+    return luaL_argerror(L, 1, "level out of range");
+  name = lua_getlocal(L, &ar, luaL_checkint(L, 2));
+  if (name) {
+    lua_pushstring(L, name);
+    lua_pushvalue(L, -2);
+    return 2;
+  }
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int setlocal (lua_State *L) {
+  lua_Debug ar;
+  if (!lua_getstack(L, luaL_checkint(L, 1), &ar))  /* level out of range? */
+    return luaL_argerror(L, 1, "level out of range");
+  luaL_checkany(L, 3);
+  lua_pushstring(L, lua_setlocal(L, &ar, luaL_checkint(L, 2)));
+  return 1;
+}
+
+
+static int auxupvalue (lua_State *L, int get) {
+  const char *name;
+  int n = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name == NULL) return 0;
+  lua_pushstring(L, name);
+  lua_insert(L, -(get+1));
+  return get + 1;
+}
+
+
+static int getupvalue (lua_State *L) {
+  return auxupvalue(L, 1);
+}
+
+
+static int setupvalue (lua_State *L) {
+  luaL_checkany(L, 3);
+  return auxupvalue(L, 0);
+}
+
+
+
+static const char KEY_HOOK = 'h';
+
+
+static void hookf (lua_State *L, lua_Debug *ar) {
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail return"};
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  if (lua_isfunction(L, -1)) {
+    lua_pushstring(L, hooknames[(int)ar->event]);
+    if (ar->currentline >= 0)
+      lua_pushnumber(L, (lua_Number)ar->currentline);
+    else lua_pushnil(L);
+    lua_assert(lua_getinfo(L, "lS", ar));
+    lua_call(L, 2, 0);
+  }
+  else
+    lua_pop(L, 1);  /* pop result from gettable */
+}
+
+
+static int makemask (const char *smask, int count) {
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+
+static char *unmakemask (int mask, char *smask) {
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+
+static int sethook (lua_State *L) {
+  if (lua_isnoneornil(L, 1)) {
+    lua_settop(L, 1);
+    lua_sethook(L, NULL, 0, 0);  /* turn off hooks */
+  }
+  else {
+    const char *smask = luaL_checkstring(L, 2);
+    int count = luaL_optint(L, 3, 0);
+    luaL_checktype(L, 1, LUA_TFUNCTION);
+    lua_sethook(L, hookf, makemask(smask, count), count);
+  }
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_pushvalue(L, 1);
+  lua_rawset(L, LUA_REGISTRYINDEX);  /* set new hook */
+  return 0;
+}
+
+
+static int gethook (lua_State *L) {
+  char buff[5];
+  int mask = lua_gethookmask(L);
+  lua_Hook hook = lua_gethook(L);
+  if (hook != NULL && hook != hookf)  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  else {
+    lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+    lua_rawget(L, LUA_REGISTRYINDEX);   /* get hook */
+  }
+  lua_pushstring(L, unmakemask(mask, buff));
+  lua_pushnumber(L, (lua_Number)lua_gethookcount(L));
+  return 3;
+}
+
+
+static int debug (lua_State *L) {
+  for (;;) {
+    char buffer[250];
+    fputs("lua_debug> ", stderr);
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+        strcmp(buffer, "cont\n") == 0)
+      return 0;
+    lua_dostring(L, buffer);
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+static int errorfb (lua_State *L) {
+  int level = 1;  /* skip level 0 (it's this function) */
+  int firstpart = 1;  /* still before eventual `...' */
+  lua_Debug ar;
+  if (lua_gettop(L) == 0)
+    lua_pushliteral(L, "");
+  else if (!lua_isstring(L, 1)) return 1;  /* no string message */
+  else lua_pushliteral(L, "\n");
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L, level++, &ar)) {
+    if (level > LEVELS1 && firstpart) {
+      /* no more than `LEVELS2' more levels? */
+      if (!lua_getstack(L, level+LEVELS2, &ar))
+        level--;  /* keep going */
+      else {
+        lua_pushliteral(L, "\n\t...");  /* too many levels */
+        while (lua_getstack(L, level+LEVELS2, &ar))  /* find last levels */
+          level++;
+      }
+      firstpart = 0;
+      continue;
+    }
+    lua_pushliteral(L, "\n\t");
+    lua_getinfo(L, "Snl", &ar);
+    lua_pushfstring(L, "%s:", ar.short_src);
+    if (ar.currentline > 0)
+      lua_pushfstring(L, "%d:", ar.currentline);
+    switch (*ar.namewhat) {
+      case 'g':  /* global */ 
+      case 'l':  /* local */
+      case 'f':  /* field */
+      case 'm':  /* method */
+        lua_pushfstring(L, " in function `%s'", ar.name);
+        break;
+      default: {
+        if (*ar.what == 'm')  /* main? */
+          lua_pushfstring(L, " in main chunk");
+        else if (*ar.what == 'C' || *ar.what == 't')
+          lua_pushliteral(L, " ?");  /* C function or tail call */
+        else
+          lua_pushfstring(L, " in function <%s:%d>",
+                             ar.short_src, ar.linedefined);
+      }
+    }
+    lua_concat(L, lua_gettop(L));
+  }
+  lua_concat(L, lua_gettop(L));
+  return 1;
+}
+
+
+static const luaL_reg dblib[] = {
+  {"getlocal", getlocal},
+  {"getinfo", getinfo},
+  {"gethook", gethook},
+  {"getupvalue", getupvalue},
+  {"sethook", sethook},
+  {"setlocal", setlocal},
+  {"setupvalue", setupvalue},
+  {"debug", debug},
+  {"traceback", errorfb},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_debug (lua_State *L) {
+  luaL_openlib(L, LUA_DBLIBNAME, dblib, 0);
+  lua_pushliteral(L, "_TRACEBACK");
+  lua_pushcfunction(L, errorfb);
+  lua_settable(L, LUA_GLOBALSINDEX);
+  return 1;
+}
+
diff --git a/lua/lib/liolib.c b/lua/lib/liolib.c
new file mode 100644
index 000000000..0ff671c1e
--- /dev/null
+++ b/lua/lib/liolib.c
@@ -0,0 +1,750 @@
+/*
+** $Id: liolib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Standard I/O (and system) library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <errno.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#define liolib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+/*
+** by default, gcc does not get `tmpname'
+*/
+#ifndef USE_TMPNAME
+#ifdef __GNUC__
+#define USE_TMPNAME	0
+#else
+#define USE_TMPNAME	1
+#endif
+#endif
+
+
+/*
+** by default, posix systems get `popen'
+*/
+#ifndef USE_POPEN
+#ifdef _POSIX_C_SOURCE
+#if _POSIX_C_SOURCE >= 2
+#define USE_POPEN	1
+#endif
+#endif
+#endif
+
+#ifndef USE_POPEN
+#define USE_POPEN	0
+#endif
+
+
+
+
+/*
+** {======================================================
+** FILE Operations
+** =======================================================
+*/
+
+
+#if !USE_POPEN
+#define pclose(f)    (-1)
+#endif
+
+
+#define FILEHANDLE		"FILE*"
+
+#define IO_INPUT		"_input"
+#define IO_OUTPUT		"_output"
+
+
+static int pushresult (lua_State *L, int i, const char *filename) {
+  if (i) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    if (filename)
+      lua_pushfstring(L, "%s: %s", filename, strerror(errno));
+    else
+      lua_pushfstring(L, "%s", strerror(errno));
+    lua_pushnumber(L, errno);
+    return 3;
+  }
+}
+
+
+static FILE **topfile (lua_State *L, int findex) {
+  FILE **f = (FILE **)luaL_checkudata(L, findex, FILEHANDLE);
+  if (f == NULL) luaL_argerror(L, findex, "bad file");
+  return f;
+}
+
+
+static int io_type (lua_State *L) {
+  FILE **f = (FILE **)luaL_checkudata(L, 1, FILEHANDLE);
+  if (f == NULL) lua_pushnil(L);
+  else if (*f == NULL)
+    lua_pushliteral(L, "closed file");
+  else
+    lua_pushliteral(L, "file");
+  return 1;
+}
+
+
+static FILE *tofile (lua_State *L, int findex) {
+  FILE **f = topfile(L, findex);
+  if (*f == NULL)
+    luaL_error(L, "attempt to use a closed file");
+  return *f;
+}
+
+
+
+/*
+** When creating file handles, always creates a `closed' file handle
+** before opening the actual file; so, if there is a memory error, the
+** file is not left opened.
+*/
+static FILE **newfile (lua_State *L) {
+  FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
+  *pf = NULL;  /* file handle is currently `closed' */
+  luaL_getmetatable(L, FILEHANDLE);
+  lua_setmetatable(L, -2);
+  return pf;
+}
+
+
+/*
+** assumes that top of the stack is the `io' library, and next is
+** the `io' metatable
+*/
+static void registerfile (lua_State *L, FILE *f, const char *name,
+                                                 const char *impname) {
+  lua_pushstring(L, name);
+  *newfile(L) = f;
+  if (impname) {
+    lua_pushstring(L, impname);
+    lua_pushvalue(L, -2);
+    lua_settable(L, -6);  /* metatable[impname] = file */
+  }
+  lua_settable(L, -3);  /* io[name] = file */
+}
+
+
+static int aux_close (lua_State *L) {
+  FILE *f = tofile(L, 1);
+  if (f == stdin || f == stdout || f == stderr)
+    return 0;  /* file cannot be closed */
+  else {
+    int ok = (pclose(f) != -1) || (fclose(f) == 0);
+    if (ok)
+      *(FILE **)lua_touserdata(L, 1) = NULL;  /* mark file as closed */
+    return ok;
+  }
+}
+
+
+static int io_close (lua_State *L) {
+  if (lua_isnone(L, 1)) {
+    lua_pushstring(L, IO_OUTPUT);
+    lua_rawget(L, lua_upvalueindex(1));
+  }
+  return pushresult(L, aux_close(L), NULL);
+}
+
+
+static int io_gc (lua_State *L) {
+  FILE **f = topfile(L, 1);
+  if (*f != NULL)  /* ignore closed files */
+    aux_close(L);
+  return 0;
+}
+
+
+static int io_tostring (lua_State *L) {
+  char buff[32];
+  FILE **f = topfile(L, 1);
+  if (*f == NULL)
+    strcpy(buff, "closed");
+  else
+    sprintf(buff, "%p", lua_touserdata(L, 1));
+  lua_pushfstring(L, "file (%s)", buff);
+  return 1;
+}
+
+
+static int io_open (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  FILE **pf = newfile(L);
+  *pf = fopen(filename, mode);
+  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+}
+
+
+static int io_popen (lua_State *L) {
+#if !USE_POPEN
+  luaL_error(L, "`popen' not supported");
+  return 0;
+#else
+  const char *filename = luaL_checkstring(L, 1);
+  const char *mode = luaL_optstring(L, 2, "r");
+  FILE **pf = newfile(L);
+  *pf = popen(filename, mode);
+  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+#endif
+}
+
+
+static int io_tmpfile (lua_State *L) {
+  FILE **pf = newfile(L);
+  *pf = tmpfile();
+  return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
+}
+
+
+static FILE *getiofile (lua_State *L, const char *name) {
+  lua_pushstring(L, name);
+  lua_rawget(L, lua_upvalueindex(1));
+  return tofile(L, -1);
+}
+
+
+static int g_iofile (lua_State *L, const char *name, const char *mode) {
+  if (!lua_isnoneornil(L, 1)) {
+    const char *filename = lua_tostring(L, 1);
+    lua_pushstring(L, name);
+    if (filename) {
+      FILE **pf = newfile(L);
+      *pf = fopen(filename, mode);
+      if (*pf == NULL) {
+        lua_pushfstring(L, "%s: %s", filename, strerror(errno));
+        luaL_argerror(L, 1, lua_tostring(L, -1));
+      }
+    }
+    else {
+      tofile(L, 1);  /* check that it's a valid file handle */
+      lua_pushvalue(L, 1);
+    }
+    lua_rawset(L, lua_upvalueindex(1));
+  }
+  /* return current value */
+  lua_pushstring(L, name);
+  lua_rawget(L, lua_upvalueindex(1));
+  return 1;
+}
+
+
+static int io_input (lua_State *L) {
+  return g_iofile(L, IO_INPUT, "r");
+}
+
+
+static int io_output (lua_State *L) {
+  return g_iofile(L, IO_OUTPUT, "w");
+}
+
+
+static int io_readline (lua_State *L);
+
+
+static void aux_lines (lua_State *L, int idx, int close) {
+  lua_pushliteral(L, FILEHANDLE);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  lua_pushvalue(L, idx);
+  lua_pushboolean(L, close);  /* close/not close file when finished */
+  lua_pushcclosure(L, io_readline, 3);
+}
+
+
+static int f_lines (lua_State *L) {
+  tofile(L, 1);  /* check that it's a valid file handle */
+  aux_lines(L, 1, 0);
+  return 1;
+}
+
+
+static int io_lines (lua_State *L) {
+  if (lua_isnoneornil(L, 1)) {  /* no arguments? */
+    lua_pushstring(L, IO_INPUT);
+    lua_rawget(L, lua_upvalueindex(1));  /* will iterate over default input */
+    return f_lines(L);
+  }
+  else {
+    const char *filename = luaL_checkstring(L, 1);
+    FILE **pf = newfile(L);
+    *pf = fopen(filename, "r");
+    luaL_argcheck(L, *pf, 1,  strerror(errno));
+    aux_lines(L, lua_gettop(L), 1);
+    return 1;
+  }
+}
+
+
+/*
+** {======================================================
+** READ
+** =======================================================
+*/
+
+
+static int read_number (lua_State *L, FILE *f) {
+  lua_Number d;
+  if (fscanf(f, LUA_NUMBER_SCAN, &d) == 1) {
+    lua_pushnumber(L, d);
+    return 1;
+  }
+  else return 0;  /* read fails */
+}
+
+
+static int test_eof (lua_State *L, FILE *f) {
+  int c = getc(f);
+  ungetc(c, f);
+  lua_pushlstring(L, NULL, 0);
+  return (c != EOF);
+}
+
+
+static int read_line (lua_State *L, FILE *f) {
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  for (;;) {
+    size_t l;
+    char *p = luaL_prepbuffer(&b);
+    if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
+      luaL_pushresult(&b);  /* close buffer */
+      return (lua_strlen(L, -1) > 0);  /* check whether read something */
+    }
+    l = strlen(p);
+    if (p[l-1] != '\n')
+      luaL_addsize(&b, l);
+    else {
+      luaL_addsize(&b, l - 1);  /* do not include `eol' */
+      luaL_pushresult(&b);  /* close buffer */
+      return 1;  /* read at least an `eol' */
+    }
+  }
+}
+
+
+static int read_chars (lua_State *L, FILE *f, size_t n) {
+  size_t rlen;  /* how much to read */
+  size_t nr;  /* number of chars actually read */
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  rlen = LUAL_BUFFERSIZE;  /* try to read that much each time */
+  do {
+    char *p = luaL_prepbuffer(&b);
+    if (rlen > n) rlen = n;  /* cannot read more than asked */
+    nr = fread(p, sizeof(char), rlen, f);
+    luaL_addsize(&b, nr);
+    n -= nr;  /* still have to read `n' chars */
+  } while (n > 0 && nr == rlen);  /* until end of count or eof */
+  luaL_pushresult(&b);  /* close buffer */
+  return (n == 0 || lua_strlen(L, -1) > 0);
+}
+
+
+static int g_read (lua_State *L, FILE *f, int first) {
+  int nargs = lua_gettop(L) - 1;
+  int success;
+  int n;
+  if (nargs == 0) {  /* no arguments? */
+    success = read_line(L, f);
+    n = first+1;  /* to return 1 result */
+  }
+  else {  /* ensure stack space for all results and for auxlib's buffer */
+    luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
+    success = 1;
+    for (n = first; nargs-- && success; n++) {
+      if (lua_type(L, n) == LUA_TNUMBER) {
+        size_t l = (size_t)lua_tonumber(L, n);
+        success = (l == 0) ? test_eof(L, f) : read_chars(L, f, l);
+      }
+      else {
+        const char *p = lua_tostring(L, n);
+        luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
+        switch (p[1]) {
+          case 'n':  /* number */
+            success = read_number(L, f);
+            break;
+          case 'l':  /* line */
+            success = read_line(L, f);
+            break;
+          case 'a':  /* file */
+            read_chars(L, f, ~((size_t)0));  /* read MAX_SIZE_T chars */
+            success = 1; /* always success */
+            break;
+          case 'w':  /* word */
+            return luaL_error(L, "obsolete option `*w' to `read'");
+          default:
+            return luaL_argerror(L, n, "invalid format");
+        }
+      }
+    }
+  }
+  if (!success) {
+    lua_pop(L, 1);  /* remove last result */
+    lua_pushnil(L);  /* push nil instead */
+  }
+  return n - first;
+}
+
+
+static int io_read (lua_State *L) {
+  return g_read(L, getiofile(L, IO_INPUT), 1);
+}
+
+
+static int f_read (lua_State *L) {
+  return g_read(L, tofile(L, 1), 2);
+}
+
+
+static int io_readline (lua_State *L) {
+  FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(2));
+  if (f == NULL)  /* file is already closed? */
+    luaL_error(L, "file is already closed");
+  if (read_line(L, f)) return 1;
+  else {  /* EOF */
+    if (lua_toboolean(L, lua_upvalueindex(3))) {  /* generator created file? */
+      lua_settop(L, 0);
+      lua_pushvalue(L, lua_upvalueindex(2));
+      aux_close(L);  /* close it */
+    }
+    return 0;
+  }
+}
+
+/* }====================================================== */
+
+
+static int g_write (lua_State *L, FILE *f, int arg) {
+  int nargs = lua_gettop(L) - 1;
+  int status = 1;
+  for (; nargs--; arg++) {
+    if (lua_type(L, arg) == LUA_TNUMBER) {
+      /* optimization: could be done exactly as for strings */
+      status = status &&
+          fprintf(f, LUA_NUMBER_FMT, lua_tonumber(L, arg)) > 0;
+    }
+    else {
+      size_t l;
+      const char *s = luaL_checklstring(L, arg, &l);
+      status = status && (fwrite(s, sizeof(char), l, f) == l);
+    }
+  }
+  return pushresult(L, status, NULL);
+}
+
+
+static int io_write (lua_State *L) {
+  return g_write(L, getiofile(L, IO_OUTPUT), 1);
+}
+
+
+static int f_write (lua_State *L) {
+  return g_write(L, tofile(L, 1), 2);
+}
+
+
+static int f_seek (lua_State *L) {
+  static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
+  static const char *const modenames[] = {"set", "cur", "end", NULL};
+  FILE *f = tofile(L, 1);
+  int op = luaL_findstring(luaL_optstring(L, 2, "cur"), modenames);
+  long offset = luaL_optlong(L, 3, 0);
+  luaL_argcheck(L, op != -1, 2, "invalid mode");
+  op = fseek(f, offset, mode[op]);
+  if (op)
+    return pushresult(L, 0, NULL);  /* error */
+  else {
+    lua_pushnumber(L, ftell(f));
+    return 1;
+  }
+}
+
+
+static int io_flush (lua_State *L) {
+  return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+}
+
+
+static int f_flush (lua_State *L) {
+  return pushresult(L, fflush(tofile(L, 1)) == 0, NULL);
+}
+
+
+static const luaL_reg iolib[] = {
+  {"input", io_input},
+  {"output", io_output},
+  {"lines", io_lines},
+  {"close", io_close},
+  {"flush", io_flush},
+  {"open", io_open},
+  {"popen", io_popen},
+  {"read", io_read},
+  {"tmpfile", io_tmpfile},
+  {"type", io_type},
+  {"write", io_write},
+  {NULL, NULL}
+};
+
+
+static const luaL_reg flib[] = {
+  {"flush", f_flush},
+  {"read", f_read},
+  {"lines", f_lines},
+  {"seek", f_seek},
+  {"write", f_write},
+  {"close", io_close},
+  {"__gc", io_gc},
+  {"__tostring", io_tostring},
+  {NULL, NULL}
+};
+
+
+static void createmeta (lua_State *L) {
+  luaL_newmetatable(L, FILEHANDLE);  /* create new metatable for file handles */
+  /* file methods */
+  lua_pushliteral(L, "__index");
+  lua_pushvalue(L, -2);  /* push metatable */
+  lua_rawset(L, -3);  /* metatable.__index = metatable */
+  luaL_openlib(L, NULL, flib, 0);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Other O.S. Operations
+** =======================================================
+*/
+
+static int io_execute (lua_State *L) {
+  lua_pushnumber(L, system(luaL_checkstring(L, 1)));
+  return 1;
+}
+
+
+static int io_remove (lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  return pushresult(L, remove(filename) == 0, filename);
+}
+
+
+static int io_rename (lua_State *L) {
+  const char *fromname = luaL_checkstring(L, 1);
+  const char *toname = luaL_checkstring(L, 2);
+  return pushresult(L, rename(fromname, toname) == 0, fromname);
+}
+
+
+static int io_tmpname (lua_State *L) {
+#if !USE_TMPNAME
+  luaL_error(L, "`tmpname' not supported");
+  return 0;
+#else
+  char buff[L_tmpnam];
+  if (tmpnam(buff) != buff)
+    return luaL_error(L, "unable to generate a unique filename in `tmpname'");
+  lua_pushstring(L, buff);
+  return 1;
+#endif
+}
+
+
+static int io_getenv (lua_State *L) {
+  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
+  return 1;
+}
+
+
+static int io_clock (lua_State *L) {
+  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** Time/Date operations
+** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
+**   wday=%w+1, yday=%j, isdst=? }
+** =======================================================
+*/
+
+static void setfield (lua_State *L, const char *key, int value) {
+  lua_pushstring(L, key);
+  lua_pushnumber(L, value);
+  lua_rawset(L, -3);
+}
+
+static void setboolfield (lua_State *L, const char *key, int value) {
+  lua_pushstring(L, key);
+  lua_pushboolean(L, value);
+  lua_rawset(L, -3);
+}
+
+static int getboolfield (lua_State *L, const char *key) {
+  int res;
+  lua_pushstring(L, key);
+  lua_gettable(L, -2);
+  res = lua_toboolean(L, -1);
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int getfield (lua_State *L, const char *key, int d) {
+  int res;
+  lua_pushstring(L, key);
+  lua_gettable(L, -2);
+  if (lua_isnumber(L, -1))
+    res = (int)(lua_tonumber(L, -1));
+  else {
+    if (d == -2)
+      return luaL_error(L, "field `%s' missing in date table", key);
+    res = d;
+  }
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int io_date (lua_State *L) {
+  const char *s = luaL_optstring(L, 1, "%c");
+  time_t t = (time_t)(luaL_optnumber(L, 2, -1));
+  struct tm *stm;
+  if (t == (time_t)(-1))  /* no time given? */
+    t = time(NULL);  /* use current time */
+  if (*s == '!') {  /* UTC? */
+    stm = gmtime(&t);
+    s++;  /* skip `!' */
+  }
+  else
+    stm = localtime(&t);
+  if (stm == NULL)  /* invalid date? */
+    lua_pushnil(L);
+  else if (strcmp(s, "*t") == 0) {
+    lua_newtable(L);
+    setfield(L, "sec", stm->tm_sec);
+    setfield(L, "min", stm->tm_min);
+    setfield(L, "hour", stm->tm_hour);
+    setfield(L, "day", stm->tm_mday);
+    setfield(L, "month", stm->tm_mon+1);
+    setfield(L, "year", stm->tm_year+1900);
+    setfield(L, "wday", stm->tm_wday+1);
+    setfield(L, "yday", stm->tm_yday+1);
+    setboolfield(L, "isdst", stm->tm_isdst);
+  }
+  else {
+    char b[256];
+    if (strftime(b, sizeof(b), s, stm))
+      lua_pushstring(L, b);
+    else
+      return luaL_error(L, "`date' format too long");
+  }
+  return 1;
+}
+
+
+static int io_time (lua_State *L) {
+  if (lua_isnoneornil(L, 1))  /* called without args? */
+    lua_pushnumber(L, time(NULL));  /* return current time */
+  else {
+    time_t t;
+    struct tm ts;
+    luaL_checktype(L, 1, LUA_TTABLE);
+    lua_settop(L, 1);  /* make sure table is at the top */
+    ts.tm_sec = getfield(L, "sec", 0);
+    ts.tm_min = getfield(L, "min", 0);
+    ts.tm_hour = getfield(L, "hour", 12);
+    ts.tm_mday = getfield(L, "day", -2);
+    ts.tm_mon = getfield(L, "month", -2) - 1;
+    ts.tm_year = getfield(L, "year", -2) - 1900;
+    ts.tm_isdst = getboolfield(L, "isdst");
+    t = mktime(&ts);
+    if (t == (time_t)(-1))
+      lua_pushnil(L);
+    else
+      lua_pushnumber(L, t);
+  }
+  return 1;
+}
+
+
+static int io_difftime (lua_State *L) {
+  lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),
+                             (time_t)(luaL_optnumber(L, 2, 0))));
+  return 1;
+}
+
+/* }====================================================== */
+
+
+static int io_setloc (lua_State *L) {
+  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
+                      LC_NUMERIC, LC_TIME};
+  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
+     "numeric", "time", NULL};
+  const char *l = lua_tostring(L, 1);
+  int op = luaL_findstring(luaL_optstring(L, 2, "all"), catnames);
+  luaL_argcheck(L, l || lua_isnoneornil(L, 1), 1, "string expected");
+  luaL_argcheck(L, op != -1, 2, "invalid option");
+  lua_pushstring(L, setlocale(cat[op], l));
+  return 1;
+}
+
+
+static int io_exit (lua_State *L) {
+  exit(luaL_optint(L, 1, EXIT_SUCCESS));
+  return 0;  /* to avoid warnings */
+}
+
+static const luaL_reg syslib[] = {
+  {"clock",     io_clock},
+  {"date",      io_date},
+  {"difftime",  io_difftime},
+  {"execute",   io_execute},
+  {"exit",      io_exit},
+  {"getenv",    io_getenv},
+  {"remove",    io_remove},
+  {"rename",    io_rename},
+  {"setlocale", io_setloc},
+  {"time",      io_time},
+  {"tmpname",   io_tmpname},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+
+LUALIB_API int luaopen_io (lua_State *L) {
+  luaL_openlib(L, LUA_OSLIBNAME, syslib, 0);
+  createmeta(L);
+  lua_pushvalue(L, -1);
+  luaL_openlib(L, LUA_IOLIBNAME, iolib, 1);
+  /* put predefined file handles into `io' table */
+  registerfile(L, stdin, "stdin", IO_INPUT);
+  registerfile(L, stdout, "stdout", IO_OUTPUT);
+  registerfile(L, stderr, "stderr", NULL);
+  return 1;
+}
+
diff --git a/lua/lib/lmathlib.c b/lua/lib/lmathlib.c
new file mode 100644
index 000000000..c5a6b14ee
--- /dev/null
+++ b/lua/lib/lmathlib.c
@@ -0,0 +1,246 @@
+/*
+** $Id: lmathlib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Standard mathematical library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+#include <math.h>
+
+#define lmathlib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#undef PI
+#define PI (3.14159265358979323846)
+#define RADIANS_PER_DEGREE (PI/180.0)
+
+
+
+/*
+** If you want Lua to operate in degrees (instead of radians),
+** define USE_DEGREES
+*/
+#ifdef USE_DEGREES
+#define FROMRAD(a)	((a)/RADIANS_PER_DEGREE)
+#define TORAD(a)	((a)*RADIANS_PER_DEGREE)
+#else
+#define FROMRAD(a)	(a)
+#define TORAD(a)	(a)
+#endif
+
+
+static int math_abs (lua_State *L) {
+  lua_pushnumber(L, fabs(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_sin (lua_State *L) {
+  lua_pushnumber(L, sin(TORAD(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_cos (lua_State *L) {
+  lua_pushnumber(L, cos(TORAD(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_tan (lua_State *L) {
+  lua_pushnumber(L, tan(TORAD(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_asin (lua_State *L) {
+  lua_pushnumber(L, FROMRAD(asin(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_acos (lua_State *L) {
+  lua_pushnumber(L, FROMRAD(acos(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_atan (lua_State *L) {
+  lua_pushnumber(L, FROMRAD(atan(luaL_checknumber(L, 1))));
+  return 1;
+}
+
+static int math_atan2 (lua_State *L) {
+  lua_pushnumber(L, FROMRAD(atan2(luaL_checknumber(L, 1), luaL_checknumber(L, 2))));
+  return 1;
+}
+
+static int math_ceil (lua_State *L) {
+  lua_pushnumber(L, ceil(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_floor (lua_State *L) {
+  lua_pushnumber(L, floor(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_mod (lua_State *L) {
+  lua_pushnumber(L, fmod(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  return 1;
+}
+
+static int math_sqrt (lua_State *L) {
+  lua_pushnumber(L, sqrt(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_pow (lua_State *L) {
+  lua_pushnumber(L, pow(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  return 1;
+}
+
+static int math_log (lua_State *L) {
+  lua_pushnumber(L, log(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_log10 (lua_State *L) {
+  lua_pushnumber(L, log10(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_exp (lua_State *L) {
+  lua_pushnumber(L, exp(luaL_checknumber(L, 1)));
+  return 1;
+}
+
+static int math_deg (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
+  return 1;
+}
+
+static int math_rad (lua_State *L) {
+  lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
+  return 1;
+}
+
+static int math_frexp (lua_State *L) {
+  int e;
+  lua_pushnumber(L, frexp(luaL_checknumber(L, 1), &e));
+  lua_pushnumber(L, e);
+  return 2;
+}
+
+static int math_ldexp (lua_State *L) {
+  lua_pushnumber(L, ldexp(luaL_checknumber(L, 1), luaL_checkint(L, 2)));
+  return 1;
+}
+
+
+
+static int math_min (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  lua_Number dmin = luaL_checknumber(L, 1);
+  int i;
+  for (i=2; i<=n; i++) {
+    lua_Number d = luaL_checknumber(L, i);
+    if (d < dmin)
+      dmin = d;
+  }
+  lua_pushnumber(L, dmin);
+  return 1;
+}
+
+
+static int math_max (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  lua_Number dmax = luaL_checknumber(L, 1);
+  int i;
+  for (i=2; i<=n; i++) {
+    lua_Number d = luaL_checknumber(L, i);
+    if (d > dmax)
+      dmax = d;
+  }
+  lua_pushnumber(L, dmax);
+  return 1;
+}
+
+
+static int math_random (lua_State *L) {
+  /* the `%' avoids the (rare) case of r==1, and is needed also because on
+     some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */
+  lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;
+  switch (lua_gettop(L)) {  /* check number of arguments */
+    case 0: {  /* no arguments */
+      lua_pushnumber(L, r);  /* Number between 0 and 1 */
+      break;
+    }
+    case 1: {  /* only upper limit */
+      int u = luaL_checkint(L, 1);
+      luaL_argcheck(L, 1<=u, 1, "interval is empty");
+      lua_pushnumber(L, (int)floor(r*u)+1);  /* int between 1 and `u' */
+      break;
+    }
+    case 2: {  /* lower and upper limits */
+      int l = luaL_checkint(L, 1);
+      int u = luaL_checkint(L, 2);
+      luaL_argcheck(L, l<=u, 2, "interval is empty");
+      lua_pushnumber(L, (int)floor(r*(u-l+1))+l);  /* int between `l' and `u' */
+      break;
+    }
+    default: return luaL_error(L, "wrong number of arguments");
+  }
+  return 1;
+}
+
+
+static int math_randomseed (lua_State *L) {
+  srand(luaL_checkint(L, 1));
+  return 0;
+}
+
+
+static const luaL_reg mathlib[] = {
+  {"abs",   math_abs},
+  {"sin",   math_sin},
+  {"cos",   math_cos},
+  {"tan",   math_tan},
+  {"asin",  math_asin},
+  {"acos",  math_acos},
+  {"atan",  math_atan},
+  {"atan2", math_atan2},
+  {"ceil",  math_ceil},
+  {"floor", math_floor},
+  {"mod",   math_mod},
+  {"frexp", math_frexp},
+  {"ldexp", math_ldexp},
+  {"sqrt",  math_sqrt},
+  {"min",   math_min},
+  {"max",   math_max},
+  {"log",   math_log},
+  {"log10", math_log10},
+  {"exp",   math_exp},
+  {"deg",   math_deg},
+  {"pow",   math_pow},
+  {"rad",   math_rad},
+  {"random",     math_random},
+  {"randomseed", math_randomseed},
+  {NULL, NULL}
+};
+
+
+/*
+** Open math library
+*/
+LUALIB_API int luaopen_math (lua_State *L) {
+  luaL_openlib(L, LUA_MATHLIBNAME, mathlib, 0);
+  lua_pushliteral(L, "pi");
+  lua_pushnumber(L, PI);
+  lua_settable(L, -3);
+  lua_pushliteral(L, "__pow");
+  lua_pushcfunction(L, math_pow);
+  lua_settable(L, LUA_GLOBALSINDEX);
+  return 1;
+}
+
diff --git a/lua/lib/loadlib.c b/lua/lib/loadlib.c
new file mode 100644
index 000000000..267cbecad
--- /dev/null
+++ b/lua/lib/loadlib.c
@@ -0,0 +1,205 @@
+/*
+** $Id: loadlib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Dynamic library loader for Lua
+** See Copyright Notice in lua.h
+*
+* This  Lua library  exports a  single function,  called loadlib,  which is
+* called from Lua  as loadlib(lib,init), where lib is the  full name of the
+* library to be  loaded (including the complete path) and  init is the name
+* of a function  to be called after the library  is loaded. Typically, this
+* function will register other functions,  thus making the complete library
+* available  to Lua.  The init  function is  *not* automatically  called by
+* loadlib. Instead,  loadlib returns  the init function  as a  Lua function
+* that the client  can call when it  thinks is appropriate. In  the case of
+* errors,  loadlib  returns  nil  and two  strings  describing  the  error.
+* The  first string  is  supplied by  the operating  system;  it should  be
+* informative and useful  for error messages. The second  string is "open",
+* "init", or  "absent" to identify  the error and is  meant to be  used for
+* making  decisions without  having to  look into  the first  string (whose
+* format is system-dependent).
+*
+* This module contains  an implementation of loadlib for  Unix systems that
+* have dlfcn, an implementation for Windows,  and a stub for other systems.
+* See  the list  at  the end  of  this  file for  some  links to  available
+* implementations of dlfcn  and interfaces to other  native dynamic loaders
+* on top of which loadlib could be implemented.
+*
+*/
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#undef LOADLIB
+
+
+#ifdef USE_DLOPEN
+#define LOADLIB
+/*
+* This is an implementation of loadlib based on the dlfcn interface.
+* The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
+* NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
+* as an emulation layer on top of native functions.
+*/
+
+#include <dlfcn.h>
+
+static int loadlib(lua_State *L)
+{
+ const char *path=luaL_checkstring(L,1);
+ const char *init=luaL_checkstring(L,2);
+ void *lib=dlopen(path,RTLD_NOW);
+ if (lib!=NULL)
+ {
+  lua_CFunction f=(lua_CFunction) dlsym(lib,init);
+  if (f!=NULL)
+  {
+   lua_pushlightuserdata(L,lib);
+   lua_pushcclosure(L,f,1);
+   return 1;
+  }
+ }
+ /* else return appropriate error messages */
+ lua_pushnil(L);
+ lua_pushstring(L,dlerror());
+ lua_pushstring(L,(lib!=NULL) ? "init" : "open");
+ if (lib!=NULL) dlclose(lib);
+ return 3;
+}
+
+#endif
+
+
+
+/*
+** In Windows, default is to use dll; otherwise, default is not to use dll
+*/
+#ifndef USE_DLL
+#ifdef _WIN32
+#define USE_DLL	1
+#else
+#define USE_DLL	0
+#endif
+#endif
+
+
+#if USE_DLL
+#define LOADLIB
+/*
+* This is an implementation of loadlib for Windows using native functions.
+*/
+
+#include <windows.h>
+
+static void pusherror(lua_State *L)
+{
+ int error=GetLastError();
+ char buffer[128];
+ if (FormatMessage(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
+	0, error, 0, buffer, sizeof(buffer), 0))
+  lua_pushstring(L,buffer);
+ else
+  lua_pushfstring(L,"system error %d\n",error);
+}
+
+static int loadlib(lua_State *L)
+{
+ const char *path=luaL_checkstring(L,1);
+ const char *init=luaL_checkstring(L,2);
+ HINSTANCE lib=LoadLibrary(path);
+ if (lib!=NULL)
+ {
+  lua_CFunction f=(lua_CFunction) GetProcAddress(lib,init);
+  if (f!=NULL)
+  {
+   lua_pushlightuserdata(L,lib);
+   lua_pushcclosure(L,f,1);
+   return 1;
+  }
+ }
+ lua_pushnil(L);
+ pusherror(L);
+ lua_pushstring(L,(lib!=NULL) ? "init" : "open");
+ if (lib!=NULL) FreeLibrary(lib);
+ return 3;
+}
+
+#endif
+
+
+
+#ifndef LOADLIB
+/* Fallback for other systems */
+
+/*
+** Those systems support dlopen, so they should have defined USE_DLOPEN.
+** The default (no)implementation gives them a special error message.
+*/
+#ifdef linux
+#define LOADLIB
+#endif
+
+#ifdef sun
+#define LOADLIB
+#endif
+
+#ifdef sgi
+#define LOADLIB
+#endif
+
+#ifdef BSD
+#define LOADLIB
+#endif
+
+#ifdef _WIN32
+#define LOADLIB
+#endif
+
+#ifdef LOADLIB
+#undef LOADLIB
+#define LOADLIB	"`loadlib' not installed (check your Lua configuration)"
+#else
+#define LOADLIB	"`loadlib' not supported"
+#endif
+
+static int loadlib(lua_State *L)
+{
+ lua_pushnil(L);
+ lua_pushliteral(L,LOADLIB);
+ lua_pushliteral(L,"absent");
+ return 3;
+}
+#endif
+
+LUALIB_API int luaopen_loadlib (lua_State *L)
+{
+ lua_register(L,"loadlib",loadlib);
+ return 0;
+}
+
+/*
+* Here are some links to available implementations of dlfcn and
+* interfaces to other native dynamic loaders on top of which loadlib
+* could be implemented. Please send contributions and corrections to us.
+*
+* AIX
+* Starting with AIX 4.2, dlfcn is included in the base OS.
+* There is also an emulation package available.
+* http://www.faqs.org/faqs/aix-faq/part4/section-21.html
+*
+* HPUX 
+* HPUX 11 has dlfcn. For HPUX 10 use shl_*.
+* http://www.geda.seul.org/mailinglist/geda-dev37/msg00094.html
+* http://www.stat.umn.edu/~luke/xls/projects/dlbasics/dlbasics.html
+*
+* Macintosh, Windows
+* http://www.stat.umn.edu/~luke/xls/projects/dlbasics/dlbasics.html
+*
+* Mac OS X/Darwin
+* http://www.opendarwin.org/projects/dlcompat/
+*
+* GLIB has wrapper code for BeOS, OS2, Unix and Windows
+* http://cvs.gnome.org/lxr/source/glib/gmodule/
+*
+*/
diff --git a/lua/lib/lstrlib.c b/lua/lib/lstrlib.c
new file mode 100644
index 000000000..9cb301f7b
--- /dev/null
+++ b/lua/lib/lstrlib.c
@@ -0,0 +1,770 @@
+/*
+** $Id: lstrlib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Standard library for string operations and pattern-matching
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lstrlib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/* macro to `unsign' a character */
+#ifndef uchar
+#define uchar(c)        ((unsigned char)(c))
+#endif
+
+
+typedef long sint32;	/* a signed version for size_t */
+
+
+static int str_len (lua_State *L) {
+  size_t l;
+  luaL_checklstring(L, 1, &l);
+  lua_pushnumber(L, (lua_Number)l);
+  return 1;
+}
+
+
+static sint32 posrelat (sint32 pos, size_t len) {
+  /* relative string position: negative means back from end */
+  return (pos>=0) ? pos : (sint32)len+pos+1;
+}
+
+
+static int str_sub (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  sint32 start = posrelat(luaL_checklong(L, 2), l);
+  sint32 end = posrelat(luaL_optlong(L, 3, -1), l);
+  if (start < 1) start = 1;
+  if (end > (sint32)l) end = (sint32)l;
+  if (start <= end)
+    lua_pushlstring(L, s+start-1, end-start+1);
+  else lua_pushliteral(L, "");
+  return 1;
+}
+
+
+static int str_lower (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  luaL_buffinit(L, &b);
+  for (i=0; i<l; i++)
+    luaL_putchar(&b, tolower(uchar(s[i])));
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_upper (lua_State *L) {
+  size_t l;
+  size_t i;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  luaL_buffinit(L, &b);
+  for (i=0; i<l; i++)
+    luaL_putchar(&b, toupper(uchar(s[i])));
+  luaL_pushresult(&b);
+  return 1;
+}
+
+static int str_rep (lua_State *L) {
+  size_t l;
+  luaL_Buffer b;
+  const char *s = luaL_checklstring(L, 1, &l);
+  int n = luaL_checkint(L, 2);
+  luaL_buffinit(L, &b);
+  while (n-- > 0)
+    luaL_addlstring(&b, s, l);
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int str_byte (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  sint32 pos = posrelat(luaL_optlong(L, 2, 1), l);
+  if (pos <= 0 || (size_t)(pos) > l)  /* index out of range? */
+    return 0;  /* no answer */
+  lua_pushnumber(L, uchar(s[pos-1]));
+  return 1;
+}
+
+
+static int str_char (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  for (i=1; i<=n; i++) {
+    int c = luaL_checkint(L, i);
+    luaL_argcheck(L, uchar(c) == c, i, "invalid value");
+    luaL_putchar(&b, uchar(c));
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static int writer (lua_State *L, const void* b, size_t size, void* B) {
+  (void)L;
+  luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
+  return 1;
+}
+
+
+static int str_dump (lua_State *L) {
+  luaL_Buffer b;
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  luaL_buffinit(L,&b);
+  if (!lua_dump(L, writer, &b))
+    luaL_error(L, "unable to dump given function");
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+
+/*
+** {======================================================
+** PATTERN MATCHING
+** =======================================================
+*/
+
+#ifndef MAX_CAPTURES
+#define MAX_CAPTURES 32  /* arbitrary limit */
+#endif
+
+
+#define CAP_UNFINISHED	(-1)
+#define CAP_POSITION	(-2)
+
+typedef struct MatchState {
+  const char *src_init;  /* init of source string */
+  const char *src_end;  /* end (`\0') of source string */
+  lua_State *L;
+  int level;  /* total number of captures (finished or unfinished) */
+  struct {
+    const char *init;
+    sint32 len;
+  } capture[MAX_CAPTURES];
+} MatchState;
+
+
+#define ESC		'%'
+#define SPECIALS	"^$*+?.([%-"
+
+
+static int check_capture (MatchState *ms, int l) {
+  l -= '1';
+  if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
+    return luaL_error(ms->L, "invalid capture index");
+  return l;
+}
+
+
+static int capture_to_close (MatchState *ms) {
+  int level = ms->level;
+  for (level--; level>=0; level--)
+    if (ms->capture[level].len == CAP_UNFINISHED) return level;
+  return luaL_error(ms->L, "invalid pattern capture");
+}
+
+
+static const char *luaI_classend (MatchState *ms, const char *p) {
+  switch (*p++) {
+    case ESC: {
+      if (*p == '\0')
+        luaL_error(ms->L, "malformed pattern (ends with `%')");
+      return p+1;
+    }
+    case '[': {
+      if (*p == '^') p++;
+      do {  /* look for a `]' */
+        if (*p == '\0')
+          luaL_error(ms->L, "malformed pattern (missing `]')");
+        if (*(p++) == ESC && *p != '\0')
+          p++;  /* skip escapes (e.g. `%]') */
+      } while (*p != ']');
+      return p+1;
+    }
+    default: {
+      return p;
+    }
+  }
+}
+
+
+static int match_class (int c, int cl) {
+  int res;
+  switch (tolower(cl)) {
+    case 'a' : res = isalpha(c); break;
+    case 'c' : res = iscntrl(c); break;
+    case 'd' : res = isdigit(c); break;
+    case 'l' : res = islower(c); break;
+    case 'p' : res = ispunct(c); break;
+    case 's' : res = isspace(c); break;
+    case 'u' : res = isupper(c); break;
+    case 'w' : res = isalnum(c); break;
+    case 'x' : res = isxdigit(c); break;
+    case 'z' : res = (c == 0); break;
+    default: return (cl == c);
+  }
+  return (islower(cl) ? res : !res);
+}
+
+
+static int matchbracketclass (int c, const char *p, const char *ec) {
+  int sig = 1;
+  if (*(p+1) == '^') {
+    sig = 0;
+    p++;  /* skip the `^' */
+  }
+  while (++p < ec) {
+    if (*p == ESC) {
+      p++;
+      if (match_class(c, *p))
+        return sig;
+    }
+    else if ((*(p+1) == '-') && (p+2 < ec)) {
+      p+=2;
+      if (uchar(*(p-2)) <= c && c <= uchar(*p))
+        return sig;
+    }
+    else if (uchar(*p) == c) return sig;
+  }
+  return !sig;
+}
+
+
+static int luaI_singlematch (int c, const char *p, const char *ep) {
+  switch (*p) {
+    case '.': return 1;  /* matches any char */
+    case ESC: return match_class(c, *(p+1));
+    case '[': return matchbracketclass(c, p, ep-1);
+    default:  return (uchar(*p) == c);
+  }
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p);
+
+
+static const char *matchbalance (MatchState *ms, const char *s,
+                                   const char *p) {
+  if (*p == 0 || *(p+1) == 0)
+    luaL_error(ms->L, "unbalanced pattern");
+  if (*s != *p) return NULL;
+  else {
+    int b = *p;
+    int e = *(p+1);
+    int cont = 1;
+    while (++s < ms->src_end) {
+      if (*s == e) {
+        if (--cont == 0) return s+1;
+      }
+      else if (*s == b) cont++;
+    }
+  }
+  return NULL;  /* string ends out of balance */
+}
+
+
+static const char *max_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  sint32 i = 0;  /* counts maximum expand for item */
+  while ((s+i)<ms->src_end && luaI_singlematch(uchar(*(s+i)), p, ep))
+    i++;
+  /* keeps trying to match with the maximum repetitions */
+  while (i>=0) {
+    const char *res = match(ms, (s+i), ep+1);
+    if (res) return res;
+    i--;  /* else didn't match; reduce 1 repetition to try again */
+  }
+  return NULL;
+}
+
+
+static const char *min_expand (MatchState *ms, const char *s,
+                                 const char *p, const char *ep) {
+  for (;;) {
+    const char *res = match(ms, s, ep+1);
+    if (res != NULL)
+      return res;
+    else if (s<ms->src_end && luaI_singlematch(uchar(*s), p, ep))
+      s++;  /* try with one more repetition */
+    else return NULL;
+  }
+}
+
+
+static const char *start_capture (MatchState *ms, const char *s,
+                                    const char *p, int what) {
+  const char *res;
+  int level = ms->level;
+  if (level >= MAX_CAPTURES) luaL_error(ms->L, "too many captures");
+  ms->capture[level].init = s;
+  ms->capture[level].len = what;
+  ms->level = level+1;
+  if ((res=match(ms, s, p)) == NULL)  /* match failed? */
+    ms->level--;  /* undo capture */
+  return res;
+}
+
+
+static const char *end_capture (MatchState *ms, const char *s,
+                                  const char *p) {
+  int l = capture_to_close(ms);
+  const char *res;
+  ms->capture[l].len = s - ms->capture[l].init;  /* close capture */
+  if ((res = match(ms, s, p)) == NULL)  /* match failed? */
+    ms->capture[l].len = CAP_UNFINISHED;  /* undo capture */
+  return res;
+}
+
+
+static const char *match_capture (MatchState *ms, const char *s, int l) {
+  size_t len;
+  l = check_capture(ms, l);
+  len = ms->capture[l].len;
+  if ((size_t)(ms->src_end-s) >= len &&
+      memcmp(ms->capture[l].init, s, len) == 0)
+    return s+len;
+  else return NULL;
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p) {
+  init: /* using goto's to optimize tail recursion */
+  switch (*p) {
+    case '(': {  /* start capture */
+      if (*(p+1) == ')')  /* position capture? */
+        return start_capture(ms, s, p+2, CAP_POSITION);
+      else
+        return start_capture(ms, s, p+1, CAP_UNFINISHED);
+    }
+    case ')': {  /* end capture */
+      return end_capture(ms, s, p+1);
+    }
+    case ESC: {
+      switch (*(p+1)) {
+        case 'b': {  /* balanced string? */
+          s = matchbalance(ms, s, p+2);
+          if (s == NULL) return NULL;
+          p+=4; goto init;  /* else return match(ms, s, p+4); */
+        }
+        case 'f': {  /* frontier? */
+          const char *ep; char previous;
+          p += 2;
+          if (*p != '[')
+            luaL_error(ms->L, "missing `[' after `%%f' in pattern");
+          ep = luaI_classend(ms, p);  /* points to what is next */
+          previous = (s == ms->src_init) ? '\0' : *(s-1);
+          if (matchbracketclass(uchar(previous), p, ep-1) ||
+             !matchbracketclass(uchar(*s), p, ep-1)) return NULL;
+          p=ep; goto init;  /* else return match(ms, s, ep); */
+        }
+        default: {
+          if (isdigit(uchar(*(p+1)))) {  /* capture results (%0-%9)? */
+            s = match_capture(ms, s, *(p+1));
+            if (s == NULL) return NULL;
+            p+=2; goto init;  /* else return match(ms, s, p+2) */
+          }
+          goto dflt;  /* case default */
+        }
+      }
+    }
+    case '\0': {  /* end of pattern */
+      return s;  /* match succeeded */
+    }
+    case '$': {
+      if (*(p+1) == '\0')  /* is the `$' the last char in pattern? */
+        return (s == ms->src_end) ? s : NULL;  /* check end of string */
+      else goto dflt;
+    }
+    default: dflt: {  /* it is a pattern item */
+      const char *ep = luaI_classend(ms, p);  /* points to what is next */
+      int m = s<ms->src_end && luaI_singlematch(uchar(*s), p, ep);
+      switch (*ep) {
+        case '?': {  /* optional */
+          const char *res;
+          if (m && ((res=match(ms, s+1, ep+1)) != NULL))
+            return res;
+          p=ep+1; goto init;  /* else return match(ms, s, ep+1); */
+        }
+        case '*': {  /* 0 or more repetitions */
+          return max_expand(ms, s, p, ep);
+        }
+        case '+': {  /* 1 or more repetitions */
+          return (m ? max_expand(ms, s+1, p, ep) : NULL);
+        }
+        case '-': {  /* 0 or more repetitions (minimum) */
+          return min_expand(ms, s, p, ep);
+        }
+        default: {
+          if (!m) return NULL;
+          s++; p=ep; goto init;  /* else return match(ms, s+1, ep); */
+        }
+      }
+    }
+  }
+}
+
+
+
+static const char *lmemfind (const char *s1, size_t l1,
+                               const char *s2, size_t l2) {
+  if (l2 == 0) return s1;  /* empty strings are everywhere */
+  else if (l2 > l1) return NULL;  /* avoids a negative `l1' */
+  else {
+    const char *init;  /* to search for a `*s2' inside `s1' */
+    l2--;  /* 1st char will be checked by `memchr' */
+    l1 = l1-l2;  /* `s2' cannot be found after that */
+    while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
+      init++;   /* 1st char is already checked */
+      if (memcmp(init, s2+1, l2) == 0)
+        return init-1;
+      else {  /* correct `l1' and `s1' to try again */
+        l1 -= init-s1;
+        s1 = init;
+      }
+    }
+    return NULL;  /* not found */
+  }
+}
+
+
+static void push_onecapture (MatchState *ms, int i) {
+  int l = ms->capture[i].len;
+  if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
+  if (l == CAP_POSITION)
+    lua_pushnumber(ms->L, (lua_Number)(ms->capture[i].init - ms->src_init + 1));
+  else
+    lua_pushlstring(ms->L, ms->capture[i].init, l);
+}
+
+
+static int push_captures (MatchState *ms, const char *s, const char *e) {
+  int i;
+  luaL_checkstack(ms->L, ms->level, "too many captures");
+  if (ms->level == 0 && s) {  /* no explicit captures? */
+    lua_pushlstring(ms->L, s, e-s);  /* return whole match */
+    return 1;
+  }
+  else {  /* return all captures */
+    for (i=0; i<ms->level; i++)
+      push_onecapture(ms, i);
+    return ms->level;  /* number of strings pushed */
+  }
+}
+
+
+static int str_find (lua_State *L) {
+  size_t l1, l2;
+  const char *s = luaL_checklstring(L, 1, &l1);
+  const char *p = luaL_checklstring(L, 2, &l2);
+  sint32 init = posrelat(luaL_optlong(L, 3, 1), l1) - 1;
+  if (init < 0) init = 0;
+  else if ((size_t)(init) > l1) init = (sint32)l1;
+  if (lua_toboolean(L, 4) ||  /* explicit request? */
+      strpbrk(p, SPECIALS) == NULL) {  /* or no special characters? */
+    /* do a plain search */
+    const char *s2 = lmemfind(s+init, l1-init, p, l2);
+    if (s2) {
+      lua_pushnumber(L, (lua_Number)(s2-s+1));
+      lua_pushnumber(L, (lua_Number)(s2-s+l2));
+      return 2;
+    }
+  }
+  else {
+    MatchState ms;
+    int anchor = (*p == '^') ? (p++, 1) : 0;
+    const char *s1=s+init;
+    ms.L = L;
+    ms.src_init = s;
+    ms.src_end = s+l1;
+    do {
+      const char *res;
+      ms.level = 0;
+      if ((res=match(&ms, s1, p)) != NULL) {
+        lua_pushnumber(L, (lua_Number)(s1-s+1));  /* start */
+        lua_pushnumber(L, (lua_Number)(res-s));   /* end */
+        return push_captures(&ms, NULL, 0) + 2;
+      }
+    } while (s1++<ms.src_end && !anchor);
+  }
+  lua_pushnil(L);  /* not found */
+  return 1;
+}
+
+
+static int gfind_aux (lua_State *L) {
+  MatchState ms;
+  const char *s = lua_tostring(L, lua_upvalueindex(1));
+  size_t ls = lua_strlen(L, lua_upvalueindex(1));
+  const char *p = lua_tostring(L, lua_upvalueindex(2));
+  const char *src;
+  ms.L = L;
+  ms.src_init = s;
+  ms.src_end = s+ls;
+  for (src = s + (size_t)lua_tonumber(L, lua_upvalueindex(3));
+       src <= ms.src_end;
+       src++) {
+    const char *e;
+    ms.level = 0;
+    if ((e = match(&ms, src, p)) != NULL) {
+      int newstart = e-s;
+      if (e == src) newstart++;  /* empty match? go at least one position */
+      lua_pushnumber(L, (lua_Number)newstart);
+      lua_replace(L, lua_upvalueindex(3));
+      return push_captures(&ms, src, e);
+    }
+  }
+  return 0;  /* not found */
+}
+
+
+static int gfind (lua_State *L) {
+  luaL_checkstring(L, 1);
+  luaL_checkstring(L, 2);
+  lua_settop(L, 2);
+  lua_pushnumber(L, 0);
+  lua_pushcclosure(L, gfind_aux, 3);
+  return 1;
+}
+
+
+static void add_s (MatchState *ms, luaL_Buffer *b,
+                   const char *s, const char *e) {
+  lua_State *L = ms->L;
+  if (lua_isstring(L, 3)) {
+    const char *news = lua_tostring(L, 3);
+    size_t l = lua_strlen(L, 3);
+    size_t i;
+    for (i=0; i<l; i++) {
+      if (news[i] != ESC)
+        luaL_putchar(b, news[i]);
+      else {
+        i++;  /* skip ESC */
+        if (!isdigit(uchar(news[i])))
+          luaL_putchar(b, news[i]);
+        else {
+          int level = check_capture(ms, news[i]);
+          push_onecapture(ms, level);
+          luaL_addvalue(b);  /* add capture to accumulated result */
+        }
+      }
+    }
+  }
+  else {  /* is a function */
+    int n;
+    lua_pushvalue(L, 3);
+    n = push_captures(ms, s, e);
+    lua_call(L, n, 1);
+    if (lua_isstring(L, -1))
+      luaL_addvalue(b);  /* add return to accumulated result */
+    else
+      lua_pop(L, 1);  /* function result is not a string: pop it */
+  }
+}
+
+
+static int str_gsub (lua_State *L) {
+  size_t srcl;
+  const char *src = luaL_checklstring(L, 1, &srcl);
+  const char *p = luaL_checkstring(L, 2);
+  int max_s = luaL_optint(L, 4, srcl+1);
+  int anchor = (*p == '^') ? (p++, 1) : 0;
+  int n = 0;
+  MatchState ms;
+  luaL_Buffer b;
+  luaL_argcheck(L,
+    lua_gettop(L) >= 3 && (lua_isstring(L, 3) || lua_isfunction(L, 3)),
+    3, "string or function expected");
+  luaL_buffinit(L, &b);
+  ms.L = L;
+  ms.src_init = src;
+  ms.src_end = src+srcl;
+  while (n < max_s) {
+    const char *e;
+    ms.level = 0;
+    e = match(&ms, src, p);
+    if (e) {
+      n++;
+      add_s(&ms, &b, src, e);
+    }
+    if (e && e>src) /* non empty match? */
+      src = e;  /* skip it */
+    else if (src < ms.src_end)
+      luaL_putchar(&b, *src++);
+    else break;
+    if (anchor) break;
+  }
+  luaL_addlstring(&b, src, ms.src_end-src);
+  luaL_pushresult(&b);
+  lua_pushnumber(L, (lua_Number)n);  /* number of substitutions */
+  return 2;
+}
+
+/* }====================================================== */
+
+
+/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
+#define MAX_ITEM	512
+/* maximum size of each format specification (such as '%-099.99d') */
+#define MAX_FORMAT	20
+
+
+static void luaI_addquoted (lua_State *L, luaL_Buffer *b, int arg) {
+  size_t l;
+  const char *s = luaL_checklstring(L, arg, &l);
+  luaL_putchar(b, '"');
+  while (l--) {
+    switch (*s) {
+      case '"': case '\\': case '\n': {
+        luaL_putchar(b, '\\');
+        luaL_putchar(b, *s);
+        break;
+      }
+      case '\0': {
+        luaL_addlstring(b, "\\000", 4);
+        break;
+      }
+      default: {
+        luaL_putchar(b, *s);
+        break;
+      }
+    }
+    s++;
+  }
+  luaL_putchar(b, '"');
+}
+
+
+static const char *scanformat (lua_State *L, const char *strfrmt,
+                                 char *form, int *hasprecision) {
+  const char *p = strfrmt;
+  while (strchr("-+ #0", *p)) p++;  /* skip flags */
+  if (isdigit(uchar(*p))) p++;  /* skip width */
+  if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  if (*p == '.') {
+    p++;
+    *hasprecision = 1;
+    if (isdigit(uchar(*p))) p++;  /* skip precision */
+    if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
+  }
+  if (isdigit(uchar(*p)))
+    luaL_error(L, "invalid format (width or precision too long)");
+  if (p-strfrmt+2 > MAX_FORMAT)  /* +2 to include `%' and the specifier */
+    luaL_error(L, "invalid format (too long)");
+  form[0] = '%';
+  strncpy(form+1, strfrmt, p-strfrmt+1);
+  form[p-strfrmt+2] = 0;
+  return p;
+}
+
+
+static int str_format (lua_State *L) {
+  int arg = 1;
+  size_t sfl;
+  const char *strfrmt = luaL_checklstring(L, arg, &sfl);
+  const char *strfrmt_end = strfrmt+sfl;
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  while (strfrmt < strfrmt_end) {
+    if (*strfrmt != '%')
+      luaL_putchar(&b, *strfrmt++);
+    else if (*++strfrmt == '%')
+      luaL_putchar(&b, *strfrmt++);  /* %% */
+    else { /* format item */
+      char form[MAX_FORMAT];  /* to store the format (`%...') */
+      char buff[MAX_ITEM];  /* to store the formatted item */
+      int hasprecision = 0;
+      if (isdigit(uchar(*strfrmt)) && *(strfrmt+1) == '$')
+        return luaL_error(L, "obsolete option (d$) to `format'");
+      arg++;
+      strfrmt = scanformat(L, strfrmt, form, &hasprecision);
+      switch (*strfrmt++) {
+        case 'c':  case 'd':  case 'i': {
+          sprintf(buff, form, luaL_checkint(L, arg));
+          break;
+        }
+        case 'o':  case 'u':  case 'x':  case 'X': {
+          sprintf(buff, form, (unsigned int)(luaL_checknumber(L, arg)));
+          break;
+        }
+        case 'e':  case 'E': case 'f':
+        case 'g': case 'G': {
+          sprintf(buff, form, luaL_checknumber(L, arg));
+          break;
+        }
+        case 'q': {
+          luaI_addquoted(L, &b, arg);
+          continue;  /* skip the `addsize' at the end */
+        }
+        case 's': {
+          size_t l;
+          const char *s = luaL_checklstring(L, arg, &l);
+          if (!hasprecision && l >= 100) {
+            /* no precision and string is too long to be formatted;
+               keep original string */
+            lua_pushvalue(L, arg);
+            luaL_addvalue(&b);
+            continue;  /* skip the `addsize' at the end */
+          }
+          else {
+            sprintf(buff, form, s);
+            break;
+          }
+        }
+        default: {  /* also treat cases `pnLlh' */
+          return luaL_error(L, "invalid option to `format'");
+        }
+      }
+      luaL_addlstring(&b, buff, strlen(buff));
+    }
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+static const luaL_reg strlib[] = {
+  {"len", str_len},
+  {"sub", str_sub},
+  {"lower", str_lower},
+  {"upper", str_upper},
+  {"char", str_char},
+  {"rep", str_rep},
+  {"byte", str_byte},
+  {"format", str_format},
+  {"dump", str_dump},
+  {"find", str_find},
+  {"gfind", gfind},
+  {"gsub", str_gsub},
+  {NULL, NULL}
+};
+
+
+/*
+** Open string library
+*/
+LUALIB_API int luaopen_string (lua_State *L) {
+  luaL_openlib(L, LUA_STRLIBNAME, strlib, 0);
+  return 1;
+}
+
diff --git a/lua/lib/ltablib.c b/lua/lib/ltablib.c
new file mode 100644
index 000000000..1ea1d6943
--- /dev/null
+++ b/lua/lib/ltablib.c
@@ -0,0 +1,250 @@
+/*
+** $Id: ltablib.c,v 1.1 2004/03/16 21:58:30 niemeyer Exp $
+** Library for Table Manipulation
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define ltablib_c
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+#define aux_getn(L,n)	(luaL_checktype(L, n, LUA_TTABLE), luaL_getn(L, n))
+
+
+static int luaB_foreachi (lua_State *L) {
+  int i;
+  int n = aux_getn(L, 1);
+  luaL_checktype(L, 2, LUA_TFUNCTION);
+  for (i=1; i<=n; i++) {
+    lua_pushvalue(L, 2);  /* function */
+    lua_pushnumber(L, (lua_Number)i);  /* 1st argument */
+    lua_rawgeti(L, 1, i);  /* 2nd argument */
+    lua_call(L, 2, 1);
+    if (!lua_isnil(L, -1))
+      return 1;
+    lua_pop(L, 1);  /* remove nil result */
+  }
+  return 0;
+}
+
+
+static int luaB_foreach (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checktype(L, 2, LUA_TFUNCTION);
+  lua_pushnil(L);  /* first key */
+  for (;;) {
+    if (lua_next(L, 1) == 0)
+      return 0;
+    lua_pushvalue(L, 2);  /* function */
+    lua_pushvalue(L, -3);  /* key */
+    lua_pushvalue(L, -3);  /* value */
+    lua_call(L, 2, 1);
+    if (!lua_isnil(L, -1))
+      return 1;
+    lua_pop(L, 2);  /* remove value and result */
+  }
+}
+
+
+static int luaB_getn (lua_State *L) {
+  lua_pushnumber(L, (lua_Number)aux_getn(L, 1));
+  return 1;
+}
+
+
+static int luaB_setn (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_setn(L, 1, luaL_checkint(L, 2));
+  return 0;
+}
+
+
+static int luaB_tinsert (lua_State *L) {
+  int v = lua_gettop(L);  /* number of arguments */
+  int n = aux_getn(L, 1) + 1;
+  int pos;  /* where to insert new element */
+  if (v == 2)  /* called with only 2 arguments */
+    pos = n;  /* insert new element at the end */
+  else {
+    pos = luaL_checkint(L, 2);  /* 2nd argument is the position */
+    if (pos > n) n = pos;  /* `grow' array if necessary */
+    v = 3;  /* function may be called with more than 3 args */
+  }
+  luaL_setn(L, 1, n);  /* new size */
+  while (--n >= pos) {  /* move up elements */
+    lua_rawgeti(L, 1, n);
+    lua_rawseti(L, 1, n+1);  /* t[n+1] = t[n] */
+  }
+  lua_pushvalue(L, v);
+  lua_rawseti(L, 1, pos);  /* t[pos] = v */
+  return 0;
+}
+
+
+static int luaB_tremove (lua_State *L) {
+  int n = aux_getn(L, 1);
+  int pos = luaL_optint(L, 2, n);
+  if (n <= 0) return 0;  /* table is `empty' */
+  luaL_setn(L, 1, n-1);  /* t.n = n-1 */
+  lua_rawgeti(L, 1, pos);  /* result = t[pos] */
+  for ( ;pos<n; pos++) {
+    lua_rawgeti(L, 1, pos+1);
+    lua_rawseti(L, 1, pos);  /* t[pos] = t[pos+1] */
+  }
+  lua_pushnil(L);
+  lua_rawseti(L, 1, n);  /* t[n] = nil */
+  return 1;
+}
+
+
+static int str_concat (lua_State *L) {
+  luaL_Buffer b;
+  size_t lsep;
+  const char *sep = luaL_optlstring(L, 2, "", &lsep);
+  int i = luaL_optint(L, 3, 1);
+  int n = luaL_optint(L, 4, 0);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  if (n == 0) n = luaL_getn(L, 1);
+  luaL_buffinit(L, &b);
+  for (; i <= n; i++) {
+    lua_rawgeti(L, 1, i);
+    luaL_argcheck(L, lua_isstring(L, -1), 1, "table contains non-strings");
+    luaL_addvalue(&b);
+    if (i != n)
+      luaL_addlstring(&b, sep, lsep);
+  }
+  luaL_pushresult(&b);
+  return 1;
+}
+
+
+
+/*
+** {======================================================
+** Quicksort
+** (based on `Algorithms in MODULA-3', Robert Sedgewick;
+**  Addison-Wesley, 1993.)
+*/
+
+
+static void set2 (lua_State *L, int i, int j) {
+  lua_rawseti(L, 1, i);
+  lua_rawseti(L, 1, j);
+}
+
+static int sort_comp (lua_State *L, int a, int b) {
+  if (!lua_isnil(L, 2)) {  /* function? */
+    int res;
+    lua_pushvalue(L, 2);
+    lua_pushvalue(L, a-1);  /* -1 to compensate function */
+    lua_pushvalue(L, b-2);  /* -2 to compensate function and `a' */
+    lua_call(L, 2, 1);
+    res = lua_toboolean(L, -1);
+    lua_pop(L, 1);
+    return res;
+  }
+  else  /* a < b? */
+    return lua_lessthan(L, a, b);
+}
+
+static void auxsort (lua_State *L, int l, int u) {
+  while (l < u) {  /* for tail recursion */
+    int i, j;
+    /* sort elements a[l], a[(l+u)/2] and a[u] */
+    lua_rawgeti(L, 1, l);
+    lua_rawgeti(L, 1, u);
+    if (sort_comp(L, -1, -2))  /* a[u] < a[l]? */
+      set2(L, l, u);  /* swap a[l] - a[u] */
+    else
+      lua_pop(L, 2);
+    if (u-l == 1) break;  /* only 2 elements */
+    i = (l+u)/2;
+    lua_rawgeti(L, 1, i);
+    lua_rawgeti(L, 1, l);
+    if (sort_comp(L, -2, -1))  /* a[i]<a[l]? */
+      set2(L, i, l);
+    else {
+      lua_pop(L, 1);  /* remove a[l] */
+      lua_rawgeti(L, 1, u);
+      if (sort_comp(L, -1, -2))  /* a[u]<a[i]? */
+        set2(L, i, u);
+      else
+        lua_pop(L, 2);
+    }
+    if (u-l == 2) break;  /* only 3 elements */
+    lua_rawgeti(L, 1, i);  /* Pivot */
+    lua_pushvalue(L, -1);
+    lua_rawgeti(L, 1, u-1);
+    set2(L, i, u-1);
+    /* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */
+    i = l; j = u-1;
+    for (;;) {  /* invariant: a[l..i] <= P <= a[j..u] */
+      /* repeat ++i until a[i] >= P */
+      while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {
+        if (i>u) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[i] */
+      }
+      /* repeat --j until a[j] <= P */
+      while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {
+        if (j<l) luaL_error(L, "invalid order function for sorting");
+        lua_pop(L, 1);  /* remove a[j] */
+      }
+      if (j<i) {
+        lua_pop(L, 3);  /* pop pivot, a[i], a[j] */
+        break;
+      }
+      set2(L, i, j);
+    }
+    lua_rawgeti(L, 1, u-1);
+    lua_rawgeti(L, 1, i);
+    set2(L, u-1, i);  /* swap pivot (a[u-1]) with a[i] */
+    /* a[l..i-1] <= a[i] == P <= a[i+1..u] */
+    /* adjust so that smaller half is in [j..i] and larger one in [l..u] */
+    if (i-l < u-i) {
+      j=l; i=i-1; l=i+2;
+    }
+    else {
+      j=i+1; i=u; u=j-2;
+    }
+    auxsort(L, j, i);  /* call recursively the smaller one */
+  }  /* repeat the routine for the larger one */
+}
+
+static int luaB_sort (lua_State *L) {
+  int n = aux_getn(L, 1);
+  luaL_checkstack(L, 40, "");  /* assume array is smaller than 2^40 */
+  if (!lua_isnoneornil(L, 2))  /* is there a 2nd argument? */
+    luaL_checktype(L, 2, LUA_TFUNCTION);
+  lua_settop(L, 2);  /* make sure there is two arguments */
+  auxsort(L, 1, n);
+  return 0;
+}
+
+/* }====================================================== */
+
+
+static const luaL_reg tab_funcs[] = {
+  {"concat", str_concat},
+  {"foreach", luaB_foreach},
+  {"foreachi", luaB_foreachi},
+  {"getn", luaB_getn},
+  {"setn", luaB_setn},
+  {"sort", luaB_sort},
+  {"insert", luaB_tinsert},
+  {"remove", luaB_tremove},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_table (lua_State *L) {
+  luaL_openlib(L, LUA_TABLIBNAME, tab_funcs, 0);
+  return 1;
+}
+