lua: get rid of bitlib and md5lib from the core, they are no longer necessary

SVN-Revision: 18138

2 files changed, 0 insertions, 670 deletions

diff --git a/package/lua/patches/410-bitlib_25-embedded.patch b/package/lua/patches/410-bitlib_25-embedded.patch
deleted file mode 100644
index 91de064..0000000
--- a/package/lua/patches/410-bitlib_25-embedded.patch
+++ /dev/null
@@ -1,186 +0,0 @@
-Index: lua-5.1.4/src/Makefile
-===================================================================
---- lua-5.1.4.orig/src/Makefile	2008-09-25 13:08:31.000000000 +0200
-+++ lua-5.1.4/src/Makefile	2008-09-25 13:08:43.000000000 +0200
-@@ -29,7 +29,7 @@
- 	lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o  \
- 	lundump.o lvm.o lzio.o lnum.o
- LIB_O=	lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o \
--	lstrlib.o loadlib.o linit.o lposix.o
-+	lstrlib.o loadlib.o linit.o lposix.o lbitlib.o
- 
- LUA_T=	lua
- LUA_O=	lua.o
-Index: lua-5.1.4/src/bit_limits.h
-===================================================================
---- /dev/null	1970-01-01 00:00:00.000000000 +0000
-+++ lua-5.1.4/src/bit_limits.h	2008-09-25 13:09:16.000000000 +0200
-@@ -0,0 +1,4 @@
-+#define BITLIB_FLOAT_BITS 53
-+#define BITLIB_FLOAT_MAX  0xfffffffffffffL
-+#define BITLIB_FLOAT_MIN  (-0x10000000000000L)
-+#define BITLIB_FLOAT_UMAX 0x1fffffffffffffUL
-Index: lua-5.1.4/src/lbitlib.c
-===================================================================
---- /dev/null	1970-01-01 00:00:00.000000000 +0000
-+++ lua-5.1.4/src/lbitlib.c	2008-09-25 13:05:15.000000000 +0200
-@@ -0,0 +1,133 @@
-+/* Bitwise operations library */
-+/* (c) Reuben Thomas 2000-2008 */
-+/* See README for license */
-+
-+#include "lua.h"
-+#include "lauxlib.h"
-+#include "limits.h"
-+
-+#include "bit_limits.h"
-+
-+
-+/* FIXME: Assume lua_Integer is int */
-+#define LUA_INTEGER_MAX INT_MAX
-+#define LUA_INTEGER_MIN INT_MIN
-+
-+/* FIXME: Assume uint is an unsigned lua_Integer */
-+typedef unsigned int lua_UInteger;
-+#define LUA_UINTEGER_MAX UINT_MAX
-+
-+
-+/* Bit type size and limits */
-+
-+#define BIT_BITS                                                        \
-+  (CHAR_BIT * sizeof(lua_Integer) > BITLIB_FLOAT_BITS ?                 \
-+   BITLIB_FLOAT_BITS : (CHAR_BIT * sizeof(lua_Integer)))
-+
-+/* This code may give warnings if BITLIB_FLOAT_* are too big to fit in
-+   long, but that doesn't matter since in that case they won't be
-+   used. */
-+#define BIT_MAX                                                         \
-+  (CHAR_BIT * sizeof(lua_Integer) > BITLIB_FLOAT_BITS ? BITLIB_FLOAT_MAX : LUA_INTEGER_MAX)
-+
-+#define BIT_MIN                                                         \
-+  (CHAR_BIT * sizeof(lua_Integer) > BITLIB_FLOAT_BITS ? BITLIB_FLOAT_MIN : LUA_INTEGER_MIN)
-+
-+#define BIT_UMAX                                                        \
-+  (CHAR_BIT * sizeof(lua_Integer) > BITLIB_FLOAT_BITS ? BITLIB_FLOAT_UMAX : LUA_UINTEGER_MAX)
-+
-+
-+/* Define TOBIT to get a bit value */
-+#ifdef BUILTIN_CAST
-+#define 
-+#define TOBIT(L, n, res)                    \
-+  ((void)(res), luaL_checkinteger((L), (n)))
-+#else
-+#include <stdint.h>
-+#include <math.h>
-+
-+/* FIXME: Assume lua_Number fits in a double (use of fmod). */
-+#define TOBIT(L, n, res)                                            \
-+  ((lua_Integer)(((res) = fmod(luaL_checknumber(L, (n)), (double)BIT_UMAX + 1.0)), \
-+                 (res) > BIT_MAX ? ((res) -= (double)BIT_UMAX, (res) -= 1) : \
-+                 ((res) < BIT_MIN ? ((res) += (double)BIT_UMAX, (res) += 1) : (res))))
-+#endif
-+
-+
-+#define BIT_TRUNCATE(i)                         \
-+  ((i) & BIT_UMAX)
-+
-+
-+/* Operations
-+
-+   The macros MONADIC and VARIADIC only deal with bitwise operations.
-+
-+   LOGICAL_SHIFT truncates its left-hand operand before shifting so
-+   that any extra bits at the most-significant end are not shifted
-+   into the result.
-+
-+   ARITHMETIC_SHIFT does not truncate its left-hand operand, so that
-+   the sign bits are not removed and right shift work properly.
-+   */
-+  
-+#define MONADIC(name, op)                                       \
-+  static int bit_ ## name(lua_State *L) {                       \
-+    lua_Number f;                                               \
-+    lua_pushinteger(L, BIT_TRUNCATE(op TOBIT(L, 1, f)));        \
-+    return 1;                                                   \
-+  }
-+
-+#define VARIADIC(name, op)                      \
-+  static int bit_ ## name(lua_State *L) {       \
-+    lua_Number f;                               \
-+    int n = lua_gettop(L), i;                   \
-+    lua_Integer w = TOBIT(L, 1, f);             \
-+    for (i = 2; i <= n; i++)                    \
-+      w op TOBIT(L, i, f);                      \
-+    lua_pushinteger(L, BIT_TRUNCATE(w));        \
-+    return 1;                                   \
-+  }
-+
-+#define LOGICAL_SHIFT(name, op)                                         \
-+  static int bit_ ## name(lua_State *L) {                               \
-+    lua_Number f;                                                       \
-+    lua_pushinteger(L, BIT_TRUNCATE(BIT_TRUNCATE((lua_UInteger)TOBIT(L, 1, f)) op \
-+                                    (unsigned)luaL_checknumber(L, 2))); \
-+    return 1;                                                           \
-+  }
-+
-+#define ARITHMETIC_SHIFT(name, op)                                      \
-+  static int bit_ ## name(lua_State *L) {                               \
-+    lua_Number f;                                                       \
-+    lua_pushinteger(L, BIT_TRUNCATE((lua_Integer)TOBIT(L, 1, f) op      \
-+                                    (unsigned)luaL_checknumber(L, 2))); \
-+    return 1;                                                           \
-+  }
-+
-+MONADIC(cast,  +)
-+MONADIC(bnot,  ~)
-+VARIADIC(band, &=)
-+VARIADIC(bor,  |=)
-+VARIADIC(bxor, ^=)
-+ARITHMETIC_SHIFT(lshift,  <<)
-+LOGICAL_SHIFT(rshift,     >>)
-+ARITHMETIC_SHIFT(arshift, >>)
-+
-+static const struct luaL_reg bitlib[] = {
-+  {"cast",    bit_cast},
-+  {"bnot",    bit_bnot},
-+  {"band",    bit_band},
-+  {"bor",     bit_bor},
-+  {"bxor",    bit_bxor},
-+  {"lshift",  bit_lshift},
-+  {"rshift",  bit_rshift},
-+  {"arshift", bit_arshift},
-+  {NULL, NULL}
-+};
-+
-+LUALIB_API int luaopen_bit (lua_State *L) {
-+  luaL_register(L, "bit", bitlib);
-+  lua_pushnumber(L, BIT_BITS);
-+  lua_setfield(L, -2, "bits");
-+  return 1;
-+}
-Index: lua-5.1.4/src/linit.c
-===================================================================
---- lua-5.1.4.orig/src/linit.c	2008-09-25 13:08:11.000000000 +0200
-+++ lua-5.1.4/src/linit.c	2008-09-25 13:08:27.000000000 +0200
-@@ -24,6 +24,7 @@
-   {LUA_MATHLIBNAME, luaopen_math},
-   {LUA_DBLIBNAME, luaopen_debug},
-   {LUA_POSIXLIBNAME, luaopen_posix},
-+  {LUA_BITLIBNAME, luaopen_bit},
-   {NULL, NULL}
- };
- 
-Index: lua-5.1.4/src/lualib.h
-===================================================================
---- lua-5.1.4.orig/src/lualib.h	2008-09-25 13:07:29.000000000 +0200
-+++ lua-5.1.4/src/lualib.h	2008-09-25 13:08:06.000000000 +0200
-@@ -42,6 +42,9 @@
- #define LUA_POSIXLIBNAME "posix"
- LUALIB_API int (luaopen_posix) (lua_State *L);
- 
-+#define LUA_BITLIBNAME	"bit"
-+LUALIB_API int (luaopen_bit) (lua_State *L);
-+
- 
- /* open all previous libraries */
- LUALIB_API void (luaL_openlibs) (lua_State *L); 
diff --git a/package/lua/patches/420-md5lib-embedded.patch b/package/lua/patches/420-md5lib-embedded.patch
deleted file mode 100644
index bac8e5d..0000000
--- a/package/lua/patches/420-md5lib-embedded.patch
+++ /dev/null
@@ -1,484 +0,0 @@
-diff -Nur lua-5.1.4.orig/src/Makefile lua-5.1.4/src/Makefile
---- lua-5.1.4.orig/src/Makefile	2009-04-27 00:36:06.000000000 +0200
-+++ lua-5.1.4/src/Makefile	2009-04-27 00:47:54.000000000 +0200
-@@ -29,7 +29,7 @@
- 	lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o  \
- 	lundump.o lvm.o lzio.o lnum.o
- LIB_O=	lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o \
--	lstrlib.o loadlib.o linit.o lposix.o lbitlib.o
-+	lstrlib.o loadlib.o linit.o lposix.o lbitlib.o md5.o md5lib.o
- 
- LUA_T=	lua
- LUA_O=	lua.o
-diff -Nur lua-5.1.4.orig/src/linit.c lua-5.1.4/src/linit.c
---- lua-5.1.4.orig/src/linit.c	2009-04-27 00:36:06.000000000 +0200
-+++ lua-5.1.4/src/linit.c	2009-04-27 00:44:54.000000000 +0200
-@@ -25,6 +25,7 @@
-   {LUA_DBLIBNAME, luaopen_debug},
-   {LUA_POSIXLIBNAME, luaopen_posix},
-   {LUA_BITLIBNAME, luaopen_bit},
-+  {LUA_MD5LIBNAME, luaopen_md5_core},
-   {NULL, NULL}
- };
- 
-diff -Nur lua-5.1.4.orig/src/lualib.h lua-5.1.4/src/lualib.h
---- lua-5.1.4.orig/src/lualib.h	2009-04-27 00:36:06.000000000 +0200
-+++ lua-5.1.4/src/lualib.h	2009-04-27 00:46:01.000000000 +0200
-@@ -45,6 +45,8 @@
- #define LUA_BITLIBNAME	"bit"
- LUALIB_API int (luaopen_bit) (lua_State *L);
- 
-+#define LUA_MD5LIBNAME "md5"
-+LUALIB_API int (luaopen_md5_core) (lua_State *L);
- 
- /* open all previous libraries */
- LUALIB_API void (luaL_openlibs) (lua_State *L); 
-diff -Nur lua-5.1.4.orig/src/md5.c lua-5.1.4/src/md5.c
---- lua-5.1.4.orig/src/md5.c	1970-01-01 01:00:00.000000000 +0100
-+++ lua-5.1.4/src/md5.c	2008-03-24 21:59:12.000000000 +0100
-@@ -0,0 +1,214 @@
-+/**
-+*  $Id: md5.c,v 1.2 2008/03/24 20:59:12 mascarenhas Exp $
-+*  Hash function MD5
-+*  @author  Marcela Ozorio Suarez, Roberto I.
-+*/
-+
-+
-+#include <string.h>
-+
-+#include "md5.h"
-+
-+
-+#define WORD 32
-+#define MASK 0xFFFFFFFF
-+#if __STDC_VERSION__ >= 199901L
-+#include <stdint.h>
-+typedef uint32_t WORD32;
-+#else
-+typedef unsigned int WORD32;
-+#endif
-+
-+
-+/**
-+*  md5 hash function.
-+*  @param message: aribtary string.
-+*  @param len: message length.
-+*  @param output: buffer to receive the hash value. Its size must be
-+*  (at least) HASHSIZE.
-+*/
-+void md5 (const char *message, long len, char *output);
-+
-+
-+
-+/*
-+** Realiza a rotacao no sentido horario dos bits da variavel 'D' do tipo WORD32.
-+** Os bits sao deslocados de 'num' posicoes
-+*/
-+#define rotate(D, num)  (D<<num) | (D>>(WORD-num))
-+
-+/*Macros que definem operacoes relizadas pelo algoritmo  md5 */
-+#define F(x, y, z) (((x) & (y)) | ((~(x)) & (z)))
-+#define G(x, y, z) (((x) & (z)) | ((y) & (~(z))))
-+#define H(x, y, z) ((x) ^ (y) ^ (z))
-+#define I(x, y, z) ((y) ^ ((x) | (~(z))))
-+
-+
-+/*vetor de numeros utilizados pelo algoritmo md5 para embaralhar bits */
-+static const WORD32 T[64]={
-+                     0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
-+                     0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
-+                     0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
-+                     0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
-+                     0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
-+                     0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
-+                     0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
-+                     0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
-+                     0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
-+                     0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
-+                     0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
-+                     0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
-+                     0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
-+                     0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
-+                     0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
-+                     0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
-+};
-+
-+
-+static void word32tobytes (const WORD32 *input, char *output) {
-+  int j = 0;
-+  while (j<4*4) {
-+    WORD32 v = *input++;
-+    output[j++] = (char)(v & 0xff); v >>= 8;
-+    output[j++] = (char)(v & 0xff); v >>= 8;
-+    output[j++] = (char)(v & 0xff); v >>= 8;
-+    output[j++] = (char)(v & 0xff);
-+  }
-+}
-+
-+
-+static void inic_digest(WORD32 *d) {
-+  d[0] = 0x67452301;
-+  d[1] = 0xEFCDAB89;
-+  d[2] = 0x98BADCFE;
-+  d[3] = 0x10325476;
-+}
-+
-+
-+/*funcao que implemeta os quatro passos principais do algoritmo MD5 */
-+static void digest(const WORD32 *m, WORD32 *d) {
-+  int j;
-+  /*MD5 PASSO1 */
-+  for (j=0; j<4*4; j+=4) {
-+    d[0] = d[0]+ F(d[1], d[2], d[3])+ m[j] + T[j];       d[0]=rotate(d[0], 7);
-+    d[0]+=d[1];
-+    d[3] = d[3]+ F(d[0], d[1], d[2])+ m[(j)+1] + T[j+1]; d[3]=rotate(d[3], 12);
-+    d[3]+=d[0];
-+    d[2] = d[2]+ F(d[3], d[0], d[1])+ m[(j)+2] + T[j+2]; d[2]=rotate(d[2], 17);
-+    d[2]+=d[3];
-+    d[1] = d[1]+ F(d[2], d[3], d[0])+ m[(j)+3] + T[j+3]; d[1]=rotate(d[1], 22);
-+    d[1]+=d[2];
-+  }
-+  /*MD5 PASSO2 */
-+  for (j=0; j<4*4; j+=4) {
-+    d[0] = d[0]+ G(d[1], d[2], d[3])+ m[(5*j+1)&0x0f] + T[(j-1)+17];
-+    d[0] = rotate(d[0],5);
-+    d[0]+=d[1];
-+    d[3] = d[3]+ G(d[0], d[1], d[2])+ m[((5*(j+1)+1)&0x0f)] + T[(j+0)+17];
-+    d[3] = rotate(d[3], 9);
-+    d[3]+=d[0];
-+    d[2] = d[2]+ G(d[3], d[0], d[1])+ m[((5*(j+2)+1)&0x0f)] + T[(j+1)+17];
-+    d[2] = rotate(d[2], 14);
-+    d[2]+=d[3];
-+    d[1] = d[1]+ G(d[2], d[3], d[0])+ m[((5*(j+3)+1)&0x0f)] + T[(j+2)+17];
-+    d[1] = rotate(d[1], 20);
-+    d[1]+=d[2];
-+  }
-+  /*MD5 PASSO3 */
-+  for (j=0; j<4*4; j+=4) {
-+    d[0] = d[0]+ H(d[1], d[2], d[3])+ m[(3*j+5)&0x0f] + T[(j-1)+33];
-+    d[0] = rotate(d[0], 4);
-+    d[0]+=d[1];
-+    d[3] = d[3]+ H(d[0], d[1], d[2])+ m[(3*(j+1)+5)&0x0f] + T[(j+0)+33];
-+    d[3] = rotate(d[3], 11);
-+    d[3]+=d[0];
-+    d[2] = d[2]+ H(d[3], d[0], d[1])+ m[(3*(j+2)+5)&0x0f] + T[(j+1)+33];
-+    d[2] = rotate(d[2], 16);
-+    d[2]+=d[3];
-+    d[1] = d[1]+ H(d[2], d[3], d[0])+ m[(3*(j+3)+5)&0x0f] + T[(j+2)+33];
-+    d[1] = rotate(d[1], 23);
-+    d[1]+=d[2];
-+  }
-+  /*MD5 PASSO4 */
-+  for (j=0; j<4*4; j+=4) {
-+    d[0] = d[0]+ I(d[1], d[2], d[3])+ m[(7*j)&0x0f] + T[(j-1)+49];
-+    d[0] = rotate(d[0], 6);
-+    d[0]+=d[1];
-+    d[3] = d[3]+ I(d[0], d[1], d[2])+ m[(7*(j+1))&0x0f] + T[(j+0)+49];
-+    d[3] = rotate(d[3], 10);
-+    d[3]+=d[0];
-+    d[2] = d[2]+ I(d[3], d[0], d[1])+ m[(7*(j+2))&0x0f] + T[(j+1)+49];
-+    d[2] = rotate(d[2], 15);
-+    d[2]+=d[3];
-+    d[1] = d[1]+ I(d[2], d[3], d[0])+ m[(7*(j+3))&0x0f] + T[(j+2)+49];
-+    d[1] = rotate(d[1], 21);
-+    d[1]+=d[2];
-+  }
-+}
-+
-+
-+static void bytestoword32 (WORD32 *x, const char *pt) {
-+  int i;
-+  for (i=0; i<16; i++) {
-+    int j=i*4;
-+    x[i] = (((WORD32)(unsigned char)pt[j+3] << 8 |
-+           (WORD32)(unsigned char)pt[j+2]) << 8 |
-+           (WORD32)(unsigned char)pt[j+1]) << 8 |
-+           (WORD32)(unsigned char)pt[j];
-+  }
-+
-+}
-+
-+
-+static void put_length(WORD32 *x, long len) {
-+  /* in bits! */
-+  x[14] = (WORD32)((len<<3) & MASK);
-+  x[15] = (WORD32)(len>>(32-3) & 0x7);
-+}
-+
-+
-+/*
-+** returned status:
-+*  0 - normal message (full 64 bytes)
-+*  1 - enough room for 0x80, but not for message length (two 4-byte words)
-+*  2 - enough room for 0x80 plus message length (at least 9 bytes free)
-+*/
-+static int converte (WORD32 *x, const char *pt, int num, int old_status) {
-+  int new_status = 0;
-+  char buff[64];
-+  if (num<64) {
-+    memcpy(buff, pt, num);  /* to avoid changing original string */
-+    memset(buff+num, 0, 64-num);
-+    if (old_status == 0)
-+      buff[num] = '\200';
-+    new_status = 1;
-+    pt = buff;
-+  }
-+  bytestoword32(x, pt);
-+  if (num <= (64 - 9))
-+    new_status = 2;
-+  return new_status;
-+}
-+
-+
-+
-+void md5 (const char *message, long len, char *output) {
-+  WORD32 d[4];
-+  int status = 0;
-+  long i = 0;
-+  inic_digest(d);
-+  while (status != 2) {
-+    WORD32 d_old[4];
-+    WORD32 wbuff[16];
-+    int numbytes = (len-i >= 64) ? 64 : len-i;
-+    /*salva os valores do vetor digest*/
-+    d_old[0]=d[0]; d_old[1]=d[1]; d_old[2]=d[2]; d_old[3]=d[3];
-+    status = converte(wbuff, message+i, numbytes, status);
-+    if (status == 2) put_length(wbuff, len);
-+    digest(wbuff, d);
-+    d[0]+=d_old[0]; d[1]+=d_old[1]; d[2]+=d_old[2]; d[3]+=d_old[3];
-+    i += numbytes;
-+  }
-+  word32tobytes(d, output);
-+}
-+
-diff -Nur lua-5.1.4.orig/src/md5.h lua-5.1.4/src/md5.h
---- lua-5.1.4.orig/src/md5.h	1970-01-01 01:00:00.000000000 +0100
-+++ lua-5.1.4/src/md5.h	2009-04-27 00:49:13.000000000 +0200
-@@ -0,0 +1,20 @@
-+/**
-+*  $Id: md5.h,v 1.2 2006/03/03 15:04:49 tomas Exp $
-+*  Cryptographic module for Lua.
-+*  @author  Roberto Ierusalimschy
-+*/
-+
-+
-+#ifndef md5_h
-+#define md5_h
-+
-+#include "lua.h"
-+
-+
-+#define HASHSIZE       16
-+
-+void md5 (const char *message, long len, char *output);
-+int luaopen_md5_core (lua_State *L);
-+
-+
-+#endif
-diff -Nur lua-5.1.4.orig/src/md5lib.c lua-5.1.4/src/md5lib.c
---- lua-5.1.4.orig/src/md5lib.c	1970-01-01 01:00:00.000000000 +0100
-+++ lua-5.1.4/src/md5lib.c	2009-04-27 00:49:55.000000000 +0200
-@@ -0,0 +1,203 @@
-+/**
-+*  $Id: md5lib.c,v 1.10 2008/05/12 20:51:27 carregal Exp $
-+*  Cryptographic and Hash functions for Lua
-+*  @author  Roberto Ierusalimschy
-+*/
-+
-+
-+#include <stdlib.h>
-+#include <string.h>
-+#include <time.h>
-+
-+#include "lua.h"
-+#include "lauxlib.h"
-+
-+#if ! defined (LUA_VERSION_NUM) || LUA_VERSION_NUM < 501
-+#include "compat-5.1.h"
-+#endif
-+
-+#include "md5.h"
-+
-+
-+/**
-+*  Hash function. Returns a hash for a given string.
-+*  @param message: arbitrary binary string.
-+*  @return  A 128-bit hash string.
-+*/
-+static int lmd5 (lua_State *L) {
-+  char buff[16];
-+  size_t l;
-+  const char *message = luaL_checklstring(L, 1, &l);
-+  md5(message, l, buff);
-+  lua_pushlstring(L, buff, 16L);
-+  return 1;
-+}
-+
-+
-+/**
-+*  X-Or. Does a bit-a-bit exclusive-or of two strings.
-+*  @param s1: arbitrary binary string.
-+*  @param s2: arbitrary binary string with same length as s1.
-+*  @return  a binary string with same length as s1 and s2,
-+*   where each bit is the exclusive-or of the corresponding bits in s1-s2.
-+*/
-+static int ex_or (lua_State *L) {
-+  size_t l1, l2;
-+  const char *s1 = luaL_checklstring(L, 1, &l1);
-+  const char *s2 = luaL_checklstring(L, 2, &l2);
-+  luaL_Buffer b;
-+  luaL_argcheck( L, l1 == l2, 2, "lengths must be equal" );
-+  luaL_buffinit(L, &b);
-+  while (l1--) luaL_putchar(&b, (*s1++)^(*s2++));
-+  luaL_pushresult(&b);
-+  return 1;
-+}
-+
-+
-+static void checkseed (lua_State *L) {
-+  if (lua_isnone(L, 3)) {  /* no seed? */
-+    time_t tm = time(NULL);  /* for `random' seed */
-+    lua_pushlstring(L, (char *)&tm, sizeof(tm));
-+  }
-+}
-+
-+
-+#define MAXKEY	256
-+#define BLOCKSIZE	16
-+
-+
-+
-+static int initblock (lua_State *L, const char *seed, int lseed, char *block) {
-+  size_t lkey;
-+  const char *key = luaL_checklstring(L, 2, &lkey);
-+  if (lkey > MAXKEY)
-+    luaL_error(L, "key too long (> %d)", MAXKEY);
-+  memset(block, 0, BLOCKSIZE);
-+  memcpy(block, seed, lseed);
-+  memcpy(block+BLOCKSIZE, key, lkey);
-+  return (int)lkey+BLOCKSIZE;
-+}
-+
-+
-+static void codestream (lua_State *L, const char *msg, size_t lmsg,
-+                                      char *block, int lblock) {
-+  luaL_Buffer b;
-+  luaL_buffinit(L, &b);
-+  while (lmsg > 0) {
-+    char code[BLOCKSIZE];
-+    int i;
-+    md5(block, lblock, code);
-+    for (i=0; i<BLOCKSIZE && lmsg > 0; i++, lmsg--)
-+      code[i] ^= *msg++;
-+    luaL_addlstring(&b, code, i); 
-+    memcpy(block, code, i); /* update seed */
-+  }
-+  luaL_pushresult(&b);
-+}
-+
-+
-+static void decodestream (lua_State *L, const char *cypher, size_t lcypher,
-+                          char *block, int lblock) {
-+  luaL_Buffer b;
-+  luaL_buffinit(L, &b);
-+  while (lcypher > 0) {
-+    char code[BLOCKSIZE];
-+    int i;
-+    md5(block, lblock, code);  /* update seed */
-+    for (i=0; i<BLOCKSIZE && lcypher > 0; i++, lcypher--)
-+      code[i] ^= *cypher++;
-+    luaL_addlstring(&b, code, i); 
-+    memcpy(block, cypher-i, i);
-+  }
-+  luaL_pushresult(&b);
-+}
-+
-+
-+/**
-+*  Encrypts a string. Uses the hash function md5 in CFB (Cipher-feedback
-+*  mode).
-+*  @param message: arbitrary binary string to be encrypted.
-+*  @param key: arbitrary binary string to be used as a key.
-+*  @param [seed]: optional arbitrary binary string to be used as a seed.
-+*  if no seed is provided, the function uses the result of
-+*  <code>time()</code> as a seed.  
-+*  @return  The cyphertext (as a binary string).
-+*/
-+static int crypt (lua_State *L) {
-+  size_t lmsg;
-+  const char *msg = luaL_checklstring(L, 1, &lmsg);
-+  size_t lseed;
-+  const char *seed;
-+  int lblock;
-+  char block[BLOCKSIZE+MAXKEY];
-+  checkseed(L);
-+  seed = luaL_checklstring(L, 3, &lseed);
-+  if (lseed > BLOCKSIZE)
-+    luaL_error(L, "seed too long (> %d)", BLOCKSIZE);
-+  /* put seed and seed length at the beginning of result */
-+  block[0] = (char)lseed;
-+  memcpy(block+1, seed, lseed);
-+  lua_pushlstring(L, block, lseed+1);  /* to concat with result */
-+  lblock = initblock(L, seed, lseed, block);
-+  codestream(L, msg, lmsg, block, lblock);
-+  lua_concat(L, 2);
-+  return 1;
-+}
-+
-+
-+/**
-+*  Decrypts a string. For any message, key, and seed, we have that
-+*  <code>decrypt(crypt(msg, key, seed), key) == msg</code>.
-+*  @param cyphertext: message to be decrypted (this must be the result of
-+   a previous call to <code>crypt</code>.
-+*  @param key: arbitrary binary string to be used as a key.
-+*  @return  The plaintext.
-+*/
-+static int decrypt (lua_State *L) {
-+  size_t lcyphertext;
-+  const char *cyphertext = luaL_checklstring(L, 1, &lcyphertext);
-+  size_t lseed = cyphertext[0];
-+  const char *seed = cyphertext+1;
-+  int lblock;
-+  char block[BLOCKSIZE+MAXKEY];
-+  luaL_argcheck(L, lcyphertext >= lseed+1 && lseed <= BLOCKSIZE, 1,
-+                 "invalid cyphered string");
-+  cyphertext += lseed+1;
-+  lcyphertext -= lseed+1;
-+  lblock = initblock(L, seed, lseed, block);
-+  decodestream(L, cyphertext, lcyphertext, block, lblock);
-+  return 1;
-+}
-+
-+
-+/*
-+** Assumes the table is on top of the stack.
-+*/
-+static void set_info (lua_State *L) {
-+	lua_pushliteral (L, "_COPYRIGHT");
-+	lua_pushliteral (L, "Copyright (C) 2003 PUC-Rio");
-+	lua_settable (L, -3);
-+	lua_pushliteral (L, "_DESCRIPTION");
-+	lua_pushliteral (L, "Basic cryptographic facilities");
-+	lua_settable (L, -3);
-+	lua_pushliteral (L, "_VERSION");
-+	lua_pushliteral (L, "MD5 1.1.2");
-+	lua_settable (L, -3);
-+}
-+
-+
-+static struct luaL_reg md5lib[] = {
-+  {"sum", lmd5},
-+  {"exor", ex_or},
-+  {"crypt", crypt},
-+  {"decrypt", decrypt},
-+  {NULL, NULL}
-+};
-+
-+
-+int luaopen_md5_core (lua_State *L) {
-+  luaL_register(L, "md5", md5lib);
-+  set_info (L);
-+  return 1;
-+}
-+