JSON support for Lua scripting, based on work from @lp, thanks!. We are using the good and fast cjson by Mark Pulford.

4 files changed, 1694 insertions, 2 deletions

diff --git a/deps/lua/src/Makefile b/deps/lua/src/Makefile
index d83bca269..01088abce 100644
--- a/deps/lua/src/Makefile
+++ b/deps/lua/src/Makefile
@@ -25,9 +25,9 @@ PLATS= aix ansi bsd freebsd generic linux macosx mingw posix solaris
 LUA_A=	liblua.a
 CORE_O=	lapi.o lcode.o ldebug.o ldo.o ldump.o lfunc.o lgc.o llex.o lmem.o \
 	lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o  \
-	lundump.o lvm.o lzio.o
+	lundump.o lvm.o lzio.o strbuf.o
 LIB_O=	lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o \
-	lstrlib.o loadlib.o linit.o
+	lstrlib.o loadlib.o linit.o lua_cjson.o
 
 LUA_T=	lua
 LUA_O=	lua.o
diff --git a/deps/lua/src/lua_cjson.c b/deps/lua/src/lua_cjson.c
new file mode 100644
index 000000000..d71ceb595
--- /dev/null
+++ b/deps/lua/src/lua_cjson.c
@@ -0,0 +1,1299 @@
+#define VERSION "1.0.3"
+
+/* CJSON - JSON support for Lua
+ *
+ * Copyright (c) 2010-2011  Mark Pulford <mark@kyne.com.au>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/* Caveats:
+ * - JSON "null" values are represented as lightuserdata since Lua
+ *   tables cannot contain "nil". Compare with cjson.null.
+ * - Invalid UTF-8 characters are not detected and will be passed
+ *   untouched. If required, UTF-8 error checking should be done
+ *   outside this library.
+ * - Javascript comments are not part of the JSON spec, and are not
+ *   currently supported.
+ *
+ * Note: Decoding is slower than encoding. Lua spends significant
+ *       time (30%) managing tables when parsing JSON since it is
+ *       difficult to know object/array sizes ahead of time.
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <math.h>
+#include <lua.h>
+#include <lauxlib.h>
+
+#include "strbuf.h"
+
+#ifdef MISSING_ISINF
+#define isinf(x) (!isnan(x) && isnan((x) - (x)))
+#endif
+
+#define DEFAULT_SPARSE_CONVERT 0
+#define DEFAULT_SPARSE_RATIO 2
+#define DEFAULT_SPARSE_SAFE 10
+#define DEFAULT_MAX_DEPTH 20
+#define DEFAULT_ENCODE_REFUSE_BADNUM 1
+#define DEFAULT_DECODE_REFUSE_BADNUM 0
+#define DEFAULT_ENCODE_KEEP_BUFFER 1
+
+typedef enum {
+    T_OBJ_BEGIN,
+    T_OBJ_END,
+    T_ARR_BEGIN,
+    T_ARR_END,
+    T_STRING,
+    T_NUMBER,
+    T_BOOLEAN,
+    T_NULL,
+    T_COLON,
+    T_COMMA,
+    T_END,
+    T_WHITESPACE,
+    T_ERROR,
+    T_UNKNOWN
+} json_token_type_t;
+
+static const char *json_token_type_name[] = {
+    "T_OBJ_BEGIN",
+    "T_OBJ_END",
+    "T_ARR_BEGIN",
+    "T_ARR_END",
+    "T_STRING",
+    "T_NUMBER",
+    "T_BOOLEAN",
+    "T_NULL",
+    "T_COLON",
+    "T_COMMA",
+    "T_END",
+    "T_WHITESPACE",
+    "T_ERROR",
+    "T_UNKNOWN",
+    NULL
+};
+
+typedef struct {
+    json_token_type_t ch2token[256];
+    char escape2char[256];  /* Decoding */
+#if 0
+    char escapes[35][8];    /* Pre-generated escape string buffer */
+    char *char2escape[256]; /* Encoding */
+#endif
+    strbuf_t encode_buf;
+    char number_fmt[8];     /* "%.XXg\0" */
+    int current_depth;
+
+    int encode_sparse_convert;
+    int encode_sparse_ratio;
+    int encode_sparse_safe;
+    int encode_max_depth;
+    int encode_refuse_badnum;
+    int decode_refuse_badnum;
+    int encode_keep_buffer;
+    int encode_number_precision;
+} json_config_t;
+
+typedef struct {
+    const char *data;
+    int index;
+    strbuf_t *tmp;    /* Temporary storage for strings */
+    json_config_t *cfg;
+} json_parse_t;
+
+typedef struct {
+    json_token_type_t type;
+    int index;
+    union {
+        const char *string;
+        double number;
+        int boolean;
+    } value;
+    int string_len;
+} json_token_t;
+
+static const char *char2escape[256] = {
+    "\\u0000", "\\u0001", "\\u0002", "\\u0003",
+    "\\u0004", "\\u0005", "\\u0006", "\\u0007",
+    "\\b", "\\t", "\\n", "\\u000b",
+    "\\f", "\\r", "\\u000e", "\\u000f",
+    "\\u0010", "\\u0011", "\\u0012", "\\u0013",
+    "\\u0014", "\\u0015", "\\u0016", "\\u0017",
+    "\\u0018", "\\u0019", "\\u001a", "\\u001b",
+    "\\u001c", "\\u001d", "\\u001e", "\\u001f",
+    NULL, NULL, "\\\"", NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, "\\/",
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, "\\\\", NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, "\\u007f",
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+};
+
+static int json_config_key;
+
+/* ===== CONFIGURATION ===== */
+
+static json_config_t *json_fetch_config(lua_State *l)
+{
+    json_config_t *cfg;
+
+    lua_pushlightuserdata(l, &json_config_key);
+    lua_gettable(l, LUA_REGISTRYINDEX);
+    cfg = lua_touserdata(l, -1);
+    if (!cfg)
+        luaL_error(l, "BUG: Unable to fetch CJSON configuration");
+
+    lua_pop(l, 1);
+
+    return cfg;
+}
+
+static void json_verify_arg_count(lua_State *l, int args)
+{
+    luaL_argcheck(l, lua_gettop(l) <= args, args + 1,
+                  "found too many arguments");
+}
+
+/* Configures handling of extremely sparse arrays:
+ * convert: Convert extremely sparse arrays into objects? Otherwise error.
+ * ratio: 0: always allow sparse; 1: never allow sparse; >1: use ratio
+ * safe: Always use an array when the max index <= safe */
+static int json_cfg_encode_sparse_array(lua_State *l)
+{
+    json_config_t *cfg;
+    int val;
+
+    json_verify_arg_count(l, 3);
+    cfg = json_fetch_config(l);
+
+    switch (lua_gettop(l)) {
+    case 3:
+        val = luaL_checkinteger(l, 3);
+        luaL_argcheck(l, val >= 0, 3, "expected integer >= 0");
+        cfg->encode_sparse_safe = val;
+    case 2:
+        val = luaL_checkinteger(l, 2);
+        luaL_argcheck(l, val >= 0, 2, "expected integer >= 0");
+        cfg->encode_sparse_ratio = val;
+    case 1:
+        luaL_argcheck(l, lua_isboolean(l, 1), 1, "expected boolean");
+        cfg->encode_sparse_convert = lua_toboolean(l, 1);
+    }
+
+    lua_pushboolean(l, cfg->encode_sparse_convert);
+    lua_pushinteger(l, cfg->encode_sparse_ratio);
+    lua_pushinteger(l, cfg->encode_sparse_safe);
+
+    return 3;
+}
+
+/* Configures the maximum number of nested arrays/objects allowed when
+ * encoding */
+static int json_cfg_encode_max_depth(lua_State *l)
+{
+    json_config_t *cfg;
+    int depth;
+
+    json_verify_arg_count(l, 1);
+    cfg = json_fetch_config(l);
+
+    if (lua_gettop(l)) {
+        depth = luaL_checkinteger(l, 1);
+        luaL_argcheck(l, depth > 0, 1, "expected positive integer");
+        cfg->encode_max_depth = depth;
+    }
+
+    lua_pushinteger(l, cfg->encode_max_depth);
+
+    return 1;
+}
+
+static void json_set_number_precision(json_config_t *cfg, int prec)
+{
+    cfg->encode_number_precision = prec;
+    sprintf(cfg->number_fmt, "%%.%dg", prec);
+}
+
+/* Configures number precision when converting doubles to text */
+static int json_cfg_encode_number_precision(lua_State *l)
+{
+    json_config_t *cfg;
+    int precision;
+
+    json_verify_arg_count(l, 1);
+    cfg = json_fetch_config(l);
+
+    if (lua_gettop(l)) {
+        precision = luaL_checkinteger(l, 1);
+        luaL_argcheck(l, 1 <= precision && precision <= 14, 1,
+                      "expected integer between 1 and 14");
+        json_set_number_precision(cfg, precision);
+    }
+
+    lua_pushinteger(l, cfg->encode_number_precision);
+
+    return 1;
+}
+
+/* Configures JSON encoding buffer persistence */
+static int json_cfg_encode_keep_buffer(lua_State *l)
+{
+    json_config_t *cfg;
+
+    json_verify_arg_count(l, 1);
+    cfg = json_fetch_config(l);
+
+    if (lua_gettop(l)) {
+        luaL_checktype(l, 1, LUA_TBOOLEAN);
+        cfg->encode_keep_buffer = lua_toboolean(l, 1);
+    }
+
+    lua_pushboolean(l, cfg->encode_keep_buffer);
+
+    return 1;
+}
+
+/* On argument: decode enum and set config variables
+ * **options must point to a NULL terminated array of 4 enums
+ * Returns: current enum value */
+static void json_enum_option(lua_State *l, const char **options,
+                             int *opt1, int *opt2)
+{
+    int setting;
+
+    if (lua_gettop(l)) {
+        if (lua_isboolean(l, 1))
+            setting = lua_toboolean(l, 1) * 3;
+        else
+            setting = luaL_checkoption(l, 1, NULL, options);
+
+        *opt1 = setting & 1 ? 1 : 0;
+        *opt2 = setting & 2 ? 1 : 0;
+    } else {
+        setting = *opt1 | (*opt2 << 1);
+    }
+
+    if (setting)
+        lua_pushstring(l, options[setting]);
+    else
+        lua_pushboolean(l, 0);
+}
+
+
+/* When enabled, rejects: NaN, Infinity, hexidecimal numbers */
+static int json_cfg_refuse_invalid_numbers(lua_State *l)
+{
+    static const char *options_enc_dec[] = { "none", "encode", "decode",
+                                             "both", NULL };
+    json_config_t *cfg;
+
+    json_verify_arg_count(l, 1);
+    cfg = json_fetch_config(l);
+
+    json_enum_option(l, options_enc_dec,
+                     &cfg->encode_refuse_badnum,
+                     &cfg->decode_refuse_badnum);
+
+    return 1;
+}
+
+static int json_destroy_config(lua_State *l)
+{
+    json_config_t *cfg;
+
+    cfg = lua_touserdata(l, 1);
+    if (cfg)
+        strbuf_free(&cfg->encode_buf);
+    cfg = NULL;
+
+    return 0;
+}
+
+static void json_create_config(lua_State *l)
+{
+    json_config_t *cfg;
+    int i;
+
+    cfg = lua_newuserdata(l, sizeof(*cfg));
+
+    /* Create GC method to clean up strbuf */
+    lua_newtable(l);
+    lua_pushcfunction(l, json_destroy_config);
+    lua_setfield(l, -2, "__gc");
+    lua_setmetatable(l, -2);
+
+    strbuf_init(&cfg->encode_buf, 0);
+
+    cfg->encode_sparse_convert = DEFAULT_SPARSE_CONVERT;
+    cfg->encode_sparse_ratio = DEFAULT_SPARSE_RATIO;
+    cfg->encode_sparse_safe = DEFAULT_SPARSE_SAFE;
+    cfg->encode_max_depth = DEFAULT_MAX_DEPTH;
+    cfg->encode_refuse_badnum = DEFAULT_ENCODE_REFUSE_BADNUM;
+    cfg->decode_refuse_badnum = DEFAULT_DECODE_REFUSE_BADNUM;
+    cfg->encode_keep_buffer = DEFAULT_ENCODE_KEEP_BUFFER;
+    json_set_number_precision(cfg, 14);
+
+    /* Decoding init */
+
+    /* Tag all characters as an error */
+    for (i = 0; i < 256; i++)
+        cfg->ch2token[i] = T_ERROR;
+
+    /* Set tokens that require no further processing */
+    cfg->ch2token['{'] = T_OBJ_BEGIN;
+    cfg->ch2token['}'] = T_OBJ_END;
+    cfg->ch2token['['] = T_ARR_BEGIN;
+    cfg->ch2token[']'] = T_ARR_END;
+    cfg->ch2token[','] = T_COMMA;
+    cfg->ch2token[':'] = T_COLON;
+    cfg->ch2token['\0'] = T_END;
+    cfg->ch2token[' '] = T_WHITESPACE;
+    cfg->ch2token['\t'] = T_WHITESPACE;
+    cfg->ch2token['\n'] = T_WHITESPACE;
+    cfg->ch2token['\r'] = T_WHITESPACE;
+
+    /* Update characters that require further processing */
+    cfg->ch2token['f'] = T_UNKNOWN;     /* false? */
+    cfg->ch2token['i'] = T_UNKNOWN;     /* inf, ininity? */
+    cfg->ch2token['I'] = T_UNKNOWN;
+    cfg->ch2token['n'] = T_UNKNOWN;     /* null, nan? */
+    cfg->ch2token['N'] = T_UNKNOWN;
+    cfg->ch2token['t'] = T_UNKNOWN;     /* true? */
+    cfg->ch2token['"'] = T_UNKNOWN;     /* string? */
+    cfg->ch2token['+'] = T_UNKNOWN;     /* number? */
+    cfg->ch2token['-'] = T_UNKNOWN;
+    for (i = 0; i < 10; i++)
+        cfg->ch2token['0' + i] = T_UNKNOWN;
+
+    /* Lookup table for parsing escape characters */
+    for (i = 0; i < 256; i++)
+        cfg->escape2char[i] = 0;          /* String error */
+    cfg->escape2char['"'] = '"';
+    cfg->escape2char['\\'] = '\\';
+    cfg->escape2char['/'] = '/';
+    cfg->escape2char['b'] = '\b';
+    cfg->escape2char['t'] = '\t';
+    cfg->escape2char['n'] = '\n';
+    cfg->escape2char['f'] = '\f';
+    cfg->escape2char['r'] = '\r';
+    cfg->escape2char['u'] = 'u';          /* Unicode parsing required */
+
+
+#if 0
+    /* Initialise separate storage for pre-generated escape codes.
+     * Escapes 0-31 map directly, 34, 92, 127 follow afterwards to
+     * save memory. */
+    for (i = 0 ; i < 32; i++)
+        sprintf(cfg->escapes[i], "\\u%04x", i);
+    strcpy(cfg->escapes[8], "\b");              /* Override simpler escapes */
+    strcpy(cfg->escapes[9], "\t");
+    strcpy(cfg->escapes[10], "\n");
+    strcpy(cfg->escapes[12], "\f");
+    strcpy(cfg->escapes[13], "\r");
+    strcpy(cfg->escapes[32], "\\\"");           /* chr(34) */
+    strcpy(cfg->escapes[33], "\\\\");           /* chr(92) */
+    sprintf(cfg->escapes[34], "\\u%04x", 127);  /* char(127) */
+
+    /* Initialise encoding escape lookup table */
+    for (i = 0; i < 32; i++)
+        cfg->char2escape[i] = cfg->escapes[i];
+    for (i = 32; i < 256; i++)
+        cfg->char2escape[i] = NULL;
+    cfg->char2escape[34] = cfg->escapes[32];
+    cfg->char2escape[92] = cfg->escapes[33];
+    cfg->char2escape[127] = cfg->escapes[34];
+#endif
+}
+
+/* ===== ENCODING ===== */
+
+static void json_encode_exception(lua_State *l, json_config_t *cfg, int lindex,
+                                  const char *reason)
+{
+    if (!cfg->encode_keep_buffer)
+        strbuf_free(&cfg->encode_buf);
+    luaL_error(l, "Cannot serialise %s: %s",
+                  lua_typename(l, lua_type(l, lindex)), reason);
+}
+
+/* json_append_string args:
+ * - lua_State
+ * - JSON strbuf
+ * - String (Lua stack index)
+ *
+ * Returns nothing. Doesn't remove string from Lua stack */
+static void json_append_string(lua_State *l, strbuf_t *json, int lindex)
+{
+    const char *escstr;
+    int i;
+    const char *str;
+    size_t len;
+
+    str = lua_tolstring(l, lindex, &len);
+
+    /* Worst case is len * 6 (all unicode escapes).
+     * This buffer is reused constantly for small strings
+     * If there are any excess pages, they won't be hit anyway.
+     * This gains ~5% speedup. */
+    strbuf_ensure_empty_length(json, len * 6 + 2);
+
+    strbuf_append_char_unsafe(json, '\"');
+    for (i = 0; i < len; i++) {
+        escstr = char2escape[(unsigned char)str[i]];
+        if (escstr)
+            strbuf_append_string(json, escstr);
+        else
+            strbuf_append_char_unsafe(json, str[i]);
+    }
+    strbuf_append_char_unsafe(json, '\"');
+}
+
+/* Find the size of the array on the top of the Lua stack
+ * -1   object (not a pure array)
+ * >=0  elements in array
+ */
+static int lua_array_length(lua_State *l, json_config_t *cfg)
+{
+    double k;
+    int max;
+    int items;
+
+    max = 0;
+    items = 0;
+
+    lua_pushnil(l);
+    /* table, startkey */
+    while (lua_next(l, -2) != 0) {
+        /* table, key, value */
+        if (lua_type(l, -2) == LUA_TNUMBER &&
+            (k = lua_tonumber(l, -2))) {
+            /* Integer >= 1 ? */
+            if (floor(k) == k && k >= 1) {
+                if (k > max)
+                    max = k;
+                items++;
+                lua_pop(l, 1);
+                continue;
+            }
+        }
+
+        /* Must not be an array (non integer key) */
+        lua_pop(l, 2);
+        return -1;
+    }
+
+    /* Encode excessively sparse arrays as objects (if enabled) */
+    if (cfg->encode_sparse_ratio > 0 &&
+        max > items * cfg->encode_sparse_ratio &&
+        max > cfg->encode_sparse_safe) {
+        if (!cfg->encode_sparse_convert)
+            json_encode_exception(l, cfg, -1, "excessively sparse array");
+
+        return -1;
+    }
+
+    return max;
+}
+
+static void json_encode_descend(lua_State *l, json_config_t *cfg)
+{
+    cfg->current_depth++;
+
+    if (cfg->current_depth > cfg->encode_max_depth) {
+        if (!cfg->encode_keep_buffer)
+            strbuf_free(&cfg->encode_buf);
+        luaL_error(l, "Cannot serialise, excessive nesting (%d)",
+                   cfg->current_depth);
+    }
+}
+
+static void json_append_data(lua_State *l, json_config_t *cfg, strbuf_t *json);
+
+/* json_append_array args:
+ * - lua_State
+ * - JSON strbuf
+ * - Size of passwd Lua array (top of stack) */
+static void json_append_array(lua_State *l, json_config_t *cfg, strbuf_t *json,
+                              int array_length)
+{
+    int comma, i;
+
+    json_encode_descend(l, cfg);
+
+    strbuf_append_char(json, '[');
+
+    comma = 0;
+    for (i = 1; i <= array_length; i++) {
+        if (comma)
+            strbuf_append_char(json, ',');
+        else
+            comma = 1;
+
+        lua_rawgeti(l, -1, i);
+        json_append_data(l, cfg, json);
+        lua_pop(l, 1);
+    }
+
+    strbuf_append_char(json, ']');
+
+    cfg->current_depth--;
+}
+
+static void json_append_number(lua_State *l, strbuf_t *json, int index,
+                               json_config_t *cfg)
+{
+    double num = lua_tonumber(l, index);
+
+    if (cfg->encode_refuse_badnum && (isinf(num) || isnan(num)))
+        json_encode_exception(l, cfg, index, "must not be NaN or Inf");
+
+    /* Lowest double printed with %.14g is 21 characters long:
+     * -1.7976931348623e+308
+     *
+     * Use 32 to include the \0, and a few extra just in case..
+     */
+    strbuf_append_fmt(json, 32, cfg->number_fmt, num);
+}
+
+static void json_append_object(lua_State *l, json_config_t *cfg,
+                               strbuf_t *json)
+{
+    int comma, keytype;
+
+    json_encode_descend(l, cfg);
+
+    /* Object */
+    strbuf_append_char(json, '{');
+
+    lua_pushnil(l);
+    /* table, startkey */
+    comma = 0;
+    while (lua_next(l, -2) != 0) {
+        if (comma)
+            strbuf_append_char(json, ',');
+        else
+            comma = 1;
+
+        /* table, key, value */
+        keytype = lua_type(l, -2);
+        if (keytype == LUA_TNUMBER) {
+            strbuf_append_char(json, '"');
+            json_append_number(l, json, -2, cfg);
+            strbuf_append_mem(json, "\":", 2);
+        } else if (keytype == LUA_TSTRING) {
+            json_append_string(l, json, -2);
+            strbuf_append_char(json, ':');
+        } else {
+            json_encode_exception(l, cfg, -2,
+                                  "table key must be a number or string");
+            /* never returns */
+        }
+
+        /* table, key, value */
+        json_append_data(l, cfg, json);
+        lua_pop(l, 1);
+        /* table, key */
+    }
+
+    strbuf_append_char(json, '}');
+
+    cfg->current_depth--;
+}
+
+/* Serialise Lua data into JSON string. */
+static void json_append_data(lua_State *l, json_config_t *cfg, strbuf_t *json)
+{
+    int len;
+
+    switch (lua_type(l, -1)) {
+    case LUA_TSTRING:
+        json_append_string(l, json, -1);
+        break;
+    case LUA_TNUMBER:
+        json_append_number(l, json, -1, cfg);
+        break;
+    case LUA_TBOOLEAN:
+        if (lua_toboolean(l, -1))
+            strbuf_append_mem(json, "true", 4);
+        else
+            strbuf_append_mem(json, "false", 5);
+        break;
+    case LUA_TTABLE:
+        len = lua_array_length(l, cfg);
+        if (len > 0)
+            json_append_array(l, cfg, json, len);
+        else
+            json_append_object(l, cfg, json);
+        break;
+    case LUA_TNIL:
+        strbuf_append_mem(json, "null", 4);
+        break;
+    case LUA_TLIGHTUSERDATA:
+        if (lua_touserdata(l, -1) == NULL) {
+            strbuf_append_mem(json, "null", 4);
+            break;
+        }
+    default:
+        /* Remaining types (LUA_TFUNCTION, LUA_TUSERDATA, LUA_TTHREAD,
+         * and LUA_TLIGHTUSERDATA) cannot be serialised */
+        json_encode_exception(l, cfg, -1, "type not supported");
+        /* never returns */
+    }
+}
+
+static int json_encode(lua_State *l)
+{
+    json_config_t *cfg;
+    char *json;
+    int len;
+
+    /* Can't use json_verify_arg_count() since we need to ensure
+     * there is only 1 argument */
+    luaL_argcheck(l, lua_gettop(l) == 1, 1, "expected 1 argument");
+
+    cfg = json_fetch_config(l);
+    cfg->current_depth = 0;
+
+    /* Reset the persistent buffer if it exists.
+     * Otherwise allocate a new buffer. */
+    if (strbuf_allocated(&cfg->encode_buf))
+        strbuf_reset(&cfg->encode_buf);
+    else
+        strbuf_init(&cfg->encode_buf, 0);
+
+    json_append_data(l, cfg, &cfg->encode_buf);
+    json = strbuf_string(&cfg->encode_buf, &len);
+
+    lua_pushlstring(l, json, len);
+
+    if (!cfg->encode_keep_buffer)
+        strbuf_free(&cfg->encode_buf);
+
+    return 1;
+}
+
+/* ===== DECODING ===== */
+
+static void json_process_value(lua_State *l, json_parse_t *json,
+                               json_token_t *token);
+
+static int hexdigit2int(char hex)
+{
+    if ('0' <= hex  && hex <= '9')
+        return hex - '0';
+
+    /* Force lowercase */
+    hex |= 0x20;
+    if ('a' <= hex && hex <= 'f')
+        return 10 + hex - 'a';
+
+    return -1;
+}
+
+static int decode_hex4(const char *hex)
+{
+    int digit[4];
+    int i;
+
+    /* Convert ASCII hex digit to numeric digit
+     * Note: this returns an error for invalid hex digits, including
+     *       NULL */
+    for (i = 0; i < 4; i++) {
+        digit[i] = hexdigit2int(hex[i]);
+        if (digit[i] < 0) {
+            return -1;
+        }
+    }
+
+    return (digit[0] << 12) +
+           (digit[1] << 8) +
+           (digit[2] << 4) +
+            digit[3];
+}
+
+/* Converts a Unicode codepoint to UTF-8.
+ * Returns UTF-8 string length, and up to 4 bytes in *utf8 */
+static int codepoint_to_utf8(char *utf8, int codepoint)
+{
+    /* 0xxxxxxx */
+    if (codepoint <= 0x7F) {
+        utf8[0] = codepoint;
+        return 1;
+    }
+
+    /* 110xxxxx 10xxxxxx */
+    if (codepoint <= 0x7FF) {
+        utf8[0] = (codepoint >> 6) | 0xC0;
+        utf8[1] = (codepoint & 0x3F) | 0x80;
+        return 2;
+    }
+
+    /* 1110xxxx 10xxxxxx 10xxxxxx */
+    if (codepoint <= 0xFFFF) {
+        utf8[0] = (codepoint >> 12) | 0xE0;
+        utf8[1] = ((codepoint >> 6) & 0x3F) | 0x80;
+        utf8[2] = (codepoint & 0x3F) | 0x80;
+        return 3;
+    }
+
+    /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
+    if (codepoint <= 0x1FFFFF) {
+        utf8[0] = (codepoint >> 18) | 0xF0;
+        utf8[1] = ((codepoint >> 12) & 0x3F) | 0x80;
+        utf8[2] = ((codepoint >> 6) & 0x3F) | 0x80;
+        utf8[3] = (codepoint & 0x3F) | 0x80;
+        return 4;
+    }
+
+    return 0;
+}
+
+
+/* Called when index pointing to beginning of UTF-16 code escape: \uXXXX
+ * \u is guaranteed to exist, but the remaining hex characters may be
+ * missing.
+ * Translate to UTF-8 and append to temporary token string.
+ * Must advance index to the next character to be processed.
+ * Returns: 0   success
+ *          -1  error
+ */
+static int json_append_unicode_escape(json_parse_t *json)
+{
+    char utf8[4];       /* Surrogate pairs require 4 UTF-8 bytes */
+    int codepoint;
+    int surrogate_low;
+    int len;
+    int escape_len = 6;
+
+    /* Fetch UTF-16 code unit */
+    codepoint = decode_hex4(&json->data[json->index + 2]);
+    if (codepoint < 0)
+        return -1;
+
+    /* UTF-16 surrogate pairs take the following 2 byte form:
+     *      11011 x yyyyyyyyyy
+     * When x = 0: y is the high 10 bits of the codepoint
+     *      x = 1: y is the low 10 bits of the codepoint
+     *
+     * Check for a surrogate pair (high or low) */
+    if ((codepoint & 0xF800) == 0xD800) {
+        /* Error if the 1st surrogate is not high */
+        if (codepoint & 0x400)
+            return -1;
+
+        /* Ensure the next code is a unicode escape */
+        if (json->data[json->index + escape_len] != '\\' ||
+            json->data[json->index + escape_len + 1] != 'u') {
+            return -1;
+        }
+
+        /* Fetch the next codepoint */
+        surrogate_low = decode_hex4(&json->data[json->index + 2 + escape_len]);
+        if (surrogate_low < 0)
+            return -1;
+
+        /* Error if the 2nd code is not a low surrogate */
+        if ((surrogate_low & 0xFC00) != 0xDC00)
+            return -1;
+
+        /* Calculate Unicode codepoint */
+        codepoint = (codepoint & 0x3FF) << 10;
+        surrogate_low &= 0x3FF;
+        codepoint = (codepoint | surrogate_low) + 0x10000;
+        escape_len = 12;
+    }
+
+    /* Convert codepoint to UTF-8 */
+    len = codepoint_to_utf8(utf8, codepoint);
+    if (!len)
+        return -1;
+
+    /* Append bytes and advance parse index */
+    strbuf_append_mem_unsafe(json->tmp, utf8, len);
+    json->index += escape_len;
+
+    return 0;
+}
+
+static void json_set_token_error(json_token_t *token, json_parse_t *json,
+                                 const char *errtype)
+{
+    token->type = T_ERROR;
+    token->index = json->index;
+    token->value.string = errtype;
+}
+
+static void json_next_string_token(json_parse_t *json, json_token_t *token)
+{
+    char *escape2char = json->cfg->escape2char;
+    char ch;
+
+    /* Caller must ensure a string is next */
+    assert(json->data[json->index] == '"');
+
+    /* Skip " */
+    json->index++;
+
+    /* json->tmp is the temporary strbuf used to accumulate the
+     * decoded string value. */
+    strbuf_reset(json->tmp);
+    while ((ch = json->data[json->index]) != '"') {
+        if (!ch) {
+            /* Premature end of the string */
+            json_set_token_error(token, json, "unexpected end of string");
+            return;
+        }
+
+        /* Handle escapes */
+        if (ch == '\\') {
+            /* Fetch escape character */
+            ch = json->data[json->index + 1];
+
+            /* Translate escape code and append to tmp string */
+            ch = escape2char[(unsigned char)ch];
+            if (ch == 'u') {
+                if (json_append_unicode_escape(json) == 0)
+                    continue;
+
+                json_set_token_error(token, json,
+                                     "invalid unicode escape code");
+                return;
+            }
+            if (!ch) {
+                json_set_token_error(token, json, "invalid escape code");
+                return;
+            }
+
+            /* Skip '\' */
+            json->index++;
+        }
+        /* Append normal character or translated single character
+         * Unicode escapes are handled above */
+        strbuf_append_char_unsafe(json->tmp, ch);
+        json->index++;
+    }
+    json->index++;  /* Eat final quote (") */
+
+    strbuf_ensure_null(json->tmp);
+
+    token->type = T_STRING;
+    token->value.string = strbuf_string(json->tmp, &token->string_len);
+}
+
+/* JSON numbers should take the following form:
+ *      -?(0|[1-9]|[1-9][0-9]+)(.[0-9]+)?([eE][-+]?[0-9]+)?
+ *
+ * json_next_number_token() uses strtod() which allows other forms:
+ * - numbers starting with '+'
+ * - NaN, -NaN, infinity, -infinity
+ * - hexidecimal numbers
+ * - numbers with leading zeros
+ *
+ * json_is_invalid_number() detects "numbers" which may pass strtod()'s
+ * error checking, but should not be allowed with strict JSON.
+ *
+ * json_is_invalid_number() may pass numbers which cause strtod()
+ * to generate an error.
+ */
+static int json_is_invalid_number(json_parse_t *json)
+{
+    int i = json->index;
+
+    /* Reject numbers starting with + */
+    if (json->data[i] == '+')
+        return 1;
+
+    /* Skip minus sign if it exists */
+    if (json->data[i] == '-')
+        i++;
+
+    /* Reject numbers starting with 0x, or leading zeros */
+    if (json->data[i] == '0') {
+        int ch2 = json->data[i + 1];
+
+        if ((ch2 | 0x20) == 'x' ||          /* Hex */
+            ('0' <= ch2 && ch2 <= '9'))     /* Leading zero */
+            return 1;
+
+        return 0;
+    } else if (json->data[i] <= '9') {
+        return 0;                           /* Ordinary number */
+    }
+
+
+    /* Reject inf/nan */
+    if (!strncasecmp(&json->data[i], "inf", 3))
+        return 1;
+    if (!strncasecmp(&json->data[i], "nan", 3))
+        return 1;
+
+    /* Pass all other numbers which may still be invalid, but
+     * strtod() will catch them. */
+    return 0;
+}
+
+static void json_next_number_token(json_parse_t *json, json_token_t *token)
+{
+    const char *startptr;
+    char *endptr;
+
+    token->type = T_NUMBER;
+    startptr = &json->data[json->index];
+    token->value.number = strtod(&json->data[json->index], &endptr);
+    if (startptr == endptr)
+        json_set_token_error(token, json, "invalid number");
+    else
+        json->index += endptr - startptr;   /* Skip the processed number */
+
+    return;
+}
+
+/* Fills in the token struct.
+ * T_STRING will return a pointer to the json_parse_t temporary string
+ * T_ERROR will leave the json->index pointer at the error.
+ */
+static void json_next_token(json_parse_t *json, json_token_t *token)
+{
+    json_token_type_t *ch2token = json->cfg->ch2token;
+    int ch;
+
+    /* Eat whitespace. FIXME: UGLY */
+    token->type = ch2token[(unsigned char)json->data[json->index]];
+    while (token->type == T_WHITESPACE)
+        token->type = ch2token[(unsigned char)json->data[++json->index]];
+
+    token->index = json->index;
+
+    /* Don't advance the pointer for an error or the end */
+    if (token->type == T_ERROR) {
+        json_set_token_error(token, json, "invalid token");
+        return;
+    }
+
+    if (token->type == T_END) {
+        return;
+    }
+
+    /* Found a known single character token, advance index and return */
+    if (token->type != T_UNKNOWN) {
+        json->index++;
+        return;
+    }
+
+    /* Process characters which triggered T_UNKNOWN */
+    ch = json->data[json->index];
+
+    /* Must use strncmp() to match the front of the JSON string.
+     * JSON identifier must be lowercase.
+     * When strict_numbers if disabled, either case is allowed for
+     * Infinity/NaN (since we are no longer following the spec..) */
+    if (ch == '"') {
+        json_next_string_token(json, token);
+        return;
+    } else if (ch == '-' || ('0' <= ch && ch <= '9')) {
+        if (json->cfg->decode_refuse_badnum && json_is_invalid_number(json)) {
+            json_set_token_error(token, json, "invalid number");
+            return;
+        }
+        json_next_number_token(json, token);
+        return;
+    } else if (!strncmp(&json->data[json->index], "true", 4)) {
+        token->type = T_BOOLEAN;
+        token->value.boolean = 1;
+        json->index += 4;
+        return;
+    } else if (!strncmp(&json->data[json->index], "false", 5)) {
+        token->type = T_BOOLEAN;
+        token->value.boolean = 0;
+        json->index += 5;
+        return;
+    } else if (!strncmp(&json->data[json->index], "null", 4)) {
+        token->type = T_NULL;
+        json->index += 4;
+        return;
+    } else if (!json->cfg->decode_refuse_badnum &&
+               json_is_invalid_number(json)) {
+        /* When refuse_badnum is disabled, only attempt to process
+         * numbers we know are invalid JSON (Inf, NaN, hex)
+         * This is required to generate an appropriate token error,
+         * otherwise all bad tokens will register as "invalid number"
+         */
+        json_next_number_token(json, token);
+        return;
+    }
+
+    /* Token starts with t/f/n but isn't recognised above. */
+    json_set_token_error(token, json, "invalid token");
+}
+
+/* This function does not return.
+ * DO NOT CALL WITH DYNAMIC MEMORY ALLOCATED.
+ * The only supported exception is the temporary parser string
+ * json->tmp struct.
+ * json and token should exist on the stack somewhere.
+ * luaL_error() will long_jmp and release the stack */
+static void json_throw_parse_error(lua_State *l, json_parse_t *json,
+                                   const char *exp, json_token_t *token)
+{
+    const char *found;
+
+    strbuf_free(json->tmp);
+
+    if (token->type == T_ERROR)
+        found = token->value.string;
+    else
+        found = json_token_type_name[token->type];
+
+    /* Note: token->index is 0 based, display starting from 1 */
+    luaL_error(l, "Expected %s but found %s at character %d",
+               exp, found, token->index + 1);
+}
+
+static void json_decode_checkstack(lua_State *l, json_parse_t *json, int n)
+{
+    if (lua_checkstack(l, n))
+        return;
+
+    strbuf_free(json->tmp);
+    luaL_error(l, "Too many nested data structures");
+}
+
+static void json_parse_object_context(lua_State *l, json_parse_t *json)
+{
+    json_token_t token;
+
+    /* 3 slots required:
+     * .., table, key, value */
+    json_decode_checkstack(l, json, 3);
+
+    lua_newtable(l);
+
+    json_next_token(json, &token);
+
+    /* Handle empty objects */
+    if (token.type == T_OBJ_END) {
+        return;
+    }
+
+    while (1) {
+        if (token.type != T_STRING)
+            json_throw_parse_error(l, json, "object key string", &token);
+
+        /* Push key */
+        lua_pushlstring(l, token.value.string, token.string_len);
+
+        json_next_token(json, &token);
+        if (token.type != T_COLON)
+            json_throw_parse_error(l, json, "colon", &token);
+
+        /* Fetch value */
+        json_next_token(json, &token);
+        json_process_value(l, json, &token);
+
+        /* Set key = value */
+        lua_rawset(l, -3);
+
+        json_next_token(json, &token);
+
+        if (token.type == T_OBJ_END)
+            return;
+
+        if (token.type != T_COMMA)
+            json_throw_parse_error(l, json, "comma or object end", &token);
+
+        json_next_token(json, &token);
+    }
+}
+
+/* Handle the array context */
+static void json_parse_array_context(lua_State *l, json_parse_t *json)
+{
+    json_token_t token;
+    int i;
+
+    /* 2 slots required:
+     * .., table, value */
+    json_decode_checkstack(l, json, 2);
+
+    lua_newtable(l);
+
+    json_next_token(json, &token);
+
+    /* Handle empty arrays */
+    if (token.type == T_ARR_END)
+        return;
+
+    for (i = 1; ; i++) {
+        json_process_value(l, json, &token);
+        lua_rawseti(l, -2, i);            /* arr[i] = value */
+
+        json_next_token(json, &token);
+
+        if (token.type == T_ARR_END)
+            return;
+
+        if (token.type != T_COMMA)
+            json_throw_parse_error(l, json, "comma or array end", &token);
+
+        json_next_token(json, &token);
+    }
+}
+
+/* Handle the "value" context */
+static void json_process_value(lua_State *l, json_parse_t *json,
+                               json_token_t *token)
+{
+    switch (token->type) {
+    case T_STRING:
+        lua_pushlstring(l, token->value.string, token->string_len);
+        break;;
+    case T_NUMBER:
+        lua_pushnumber(l, token->value.number);
+        break;;
+    case T_BOOLEAN:
+        lua_pushboolean(l, token->value.boolean);
+        break;;
+    case T_OBJ_BEGIN:
+        json_parse_object_context(l, json);
+        break;;
+    case T_ARR_BEGIN:
+        json_parse_array_context(l, json);
+        break;;
+    case T_NULL:
+        /* In Lua, setting "t[k] = nil" will delete k from the table.
+         * Hence a NULL pointer lightuserdata object is used instead */
+        lua_pushlightuserdata(l, NULL);
+        break;;
+    default:
+        json_throw_parse_error(l, json, "value", token);
+    }
+}
+
+/* json_text must be null terminated string */
+static void lua_json_decode(lua_State *l, const char *json_text, int json_len)
+{
+    json_parse_t json;
+    json_token_t token;
+
+    json.cfg = json_fetch_config(l);
+    json.data = json_text;
+    json.index = 0;
+
+    /* Ensure the temporary buffer can hold the entire string.
+     * This means we no longer need to do length checks since the decoded
+     * string must be smaller than the entire json string */
+    json.tmp = strbuf_new(json_len);
+
+    json_next_token(&json, &token);
+    json_process_value(l, &json, &token);
+
+    /* Ensure there is no more input left */
+    json_next_token(&json, &token);
+
+    if (token.type != T_END)
+        json_throw_parse_error(l, &json, "the end", &token);
+
+    strbuf_free(json.tmp);
+}
+
+static int json_decode(lua_State *l)
+{
+    const char *json;
+    size_t len;
+
+    json_verify_arg_count(l, 1);
+
+    json = luaL_checklstring(l, 1, &len);
+
+    /* Detect Unicode other than UTF-8 (see RFC 4627, Sec 3)
+     *
+     * CJSON can support any simple data type, hence only the first
+     * character is guaranteed to be ASCII (at worst: '"'). This is
+     * still enough to detect whether the wrong encoding is in use. */
+    if (len >= 2 && (!json[0] || !json[1]))
+        luaL_error(l, "JSON parser does not support UTF-16 or UTF-32");
+
+    lua_json_decode(l, json, len);
+
+    return 1;
+}
+
+/* ===== INITIALISATION ===== */
+
+int luaopen_cjson(lua_State *l)
+{
+    luaL_Reg reg[] = {
+        { "encode", json_encode },
+        { "decode", json_decode },
+        { "encode_sparse_array", json_cfg_encode_sparse_array },
+        { "encode_max_depth", json_cfg_encode_max_depth },
+        { "encode_number_precision", json_cfg_encode_number_precision },
+        { "encode_keep_buffer", json_cfg_encode_keep_buffer },
+        { "refuse_invalid_numbers", json_cfg_refuse_invalid_numbers },
+        { NULL, NULL }
+    };
+
+    /* Use json_fetch_config as a pointer.
+     * It's faster than using a config string, and more unique */
+    lua_pushlightuserdata(l, &json_config_key);
+    json_create_config(l);
+    lua_settable(l, LUA_REGISTRYINDEX);
+
+    luaL_register(l, "cjson", reg);
+
+    /* Set cjson.null */
+    lua_pushlightuserdata(l, NULL);
+    lua_setfield(l, -2, "null");
+
+    /* Set cjson.version */
+    lua_pushliteral(l, VERSION);
+    lua_setfield(l, -2, "version");
+
+    /* Return cjson table */
+    return 1;
+}
+
+/* vi:ai et sw=4 ts=4:
+ */
diff --git a/deps/lua/src/strbuf.c b/deps/lua/src/strbuf.c
new file mode 100644
index 000000000..976925a88
--- /dev/null
+++ b/deps/lua/src/strbuf.c
@@ -0,0 +1,251 @@
+/* strbuf - string buffer routines
+ *
+ * Copyright (c) 2010-2011  Mark Pulford <mark@kyne.com.au>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "strbuf.h"
+
+void die(const char *fmt, ...)
+{
+    va_list arg;
+
+    va_start(arg, fmt);
+    vfprintf(stderr, fmt, arg);
+    va_end(arg);
+    fprintf(stderr, "\n");
+
+    exit(-1);
+}
+
+void strbuf_init(strbuf_t *s, int len)
+{
+    int size;
+
+    if (len <= 0)
+        size = STRBUF_DEFAULT_SIZE;
+    else
+        size = len + 1;         /* \0 terminator */
+
+    s->buf = NULL;
+    s->size = size;
+    s->length = 0;
+    s->increment = STRBUF_DEFAULT_INCREMENT;
+    s->dynamic = 0;
+    s->reallocs = 0;
+    s->debug = 0;
+
+    s->buf = malloc(size);
+    if (!s->buf)
+        die("Out of memory");
+
+    strbuf_ensure_null(s);
+}
+
+strbuf_t *strbuf_new(int len)
+{
+    strbuf_t *s;
+
+    s = malloc(sizeof(strbuf_t));
+    if (!s)
+        die("Out of memory");
+
+    strbuf_init(s, len);
+
+    /* Dynamic strbuf allocation / deallocation */
+    s->dynamic = 1;
+
+    return s;
+}
+
+void strbuf_set_increment(strbuf_t *s, int increment)
+{
+    /* Increment > 0:  Linear buffer growth rate
+     * Increment < -1: Exponential buffer growth rate */
+    if (increment == 0 || increment == -1)
+        die("BUG: Invalid string increment");
+
+    s->increment = increment;
+}
+
+static inline void debug_stats(strbuf_t *s)
+{
+    if (s->debug) {
+        fprintf(stderr, "strbuf(%lx) reallocs: %d, length: %d, size: %d\n",
+                (long)s, s->reallocs, s->length, s->size);
+    }
+}
+
+/* If strbuf_t has not been dynamically allocated, strbuf_free() can
+ * be called any number of times strbuf_init() */
+void strbuf_free(strbuf_t *s)
+{
+    debug_stats(s);
+
+    if (s->buf) {
+        free(s->buf);
+        s->buf = NULL;
+    }
+    if (s->dynamic)
+        free(s);
+}
+
+char *strbuf_free_to_string(strbuf_t *s, int *len)
+{
+    char *buf;
+
+    debug_stats(s);
+
+    strbuf_ensure_null(s);
+
+    buf = s->buf;
+    if (len)
+        *len = s->length;
+
+    if (s->dynamic)
+        free(s);
+
+    return buf;
+}
+
+static int calculate_new_size(strbuf_t *s, int len)
+{
+    int reqsize, newsize;
+
+    if (len <= 0)
+        die("BUG: Invalid strbuf length requested");
+
+    /* Ensure there is room for optional NULL termination */
+    reqsize = len + 1;
+
+    /* If the user has requested to shrink the buffer, do it exactly */
+    if (s->size > reqsize)
+        return reqsize;
+
+    newsize = s->size;
+    if (s->increment < 0) {
+        /* Exponential sizing */
+        while (newsize < reqsize)
+            newsize *= -s->increment;
+    } else {
+        /* Linear sizing */
+        newsize = ((newsize + s->increment - 1) / s->increment) * s->increment;
+    }
+
+    return newsize;
+}
+
+
+/* Ensure strbuf can handle a string length bytes long (ignoring NULL
+ * optional termination). */
+void strbuf_resize(strbuf_t *s, int len)
+{
+    int newsize;
+
+    newsize = calculate_new_size(s, len);
+
+    if (s->debug > 1) {
+        fprintf(stderr, "strbuf(%lx) resize: %d => %d\n",
+                (long)s, s->size, newsize);
+    }
+
+    s->size = newsize;
+    s->buf = realloc(s->buf, s->size);
+    if (!s->buf)
+        die("Out of memory");
+    s->reallocs++;
+}
+
+void strbuf_append_string(strbuf_t *s, const char *str)
+{
+    int space, i;
+
+    space = strbuf_empty_length(s);
+
+    for (i = 0; str[i]; i++) {
+        if (space < 1) {
+            strbuf_resize(s, s->length + 1);
+            space = strbuf_empty_length(s);
+        }
+
+        s->buf[s->length] = str[i];
+        s->length++;
+        space--;
+    }
+}
+
+/* strbuf_append_fmt() should only be used when an upper bound
+ * is known for the output string. */
+void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...)
+{
+    va_list arg;
+    int fmt_len;
+
+    strbuf_ensure_empty_length(s, len);
+
+    va_start(arg, fmt);
+    fmt_len = vsnprintf(s->buf + s->length, len, fmt, arg);
+    va_end(arg);
+
+    if (fmt_len < 0)
+        die("BUG: Unable to convert number");  /* This should never happen.. */
+
+    s->length += fmt_len;
+}
+
+/* strbuf_append_fmt_retry() can be used when the there is no known
+ * upper bound for the output string. */
+void strbuf_append_fmt_retry(strbuf_t *s, const char *fmt, ...)
+{
+    va_list arg;
+    int fmt_len, try;
+    int empty_len;
+
+    /* If the first attempt to append fails, resize the buffer appropriately
+     * and try again */
+    for (try = 0; ; try++) {
+        va_start(arg, fmt);
+        /* Append the new formatted string */
+        /* fmt_len is the length of the string required, excluding the
+         * trailing NULL */
+        empty_len = strbuf_empty_length(s);
+        /* Add 1 since there is also space to store the terminating NULL. */
+        fmt_len = vsnprintf(s->buf + s->length, empty_len + 1, fmt, arg);
+        va_end(arg);
+
+        if (fmt_len <= empty_len)
+            break;  /* SUCCESS */
+        if (try > 0)
+            die("BUG: length of formatted string changed");
+
+        strbuf_resize(s, s->length + fmt_len);
+    }
+
+    s->length += fmt_len;
+}
+
+/* vi:ai et sw=4 ts=4:
+ */
diff --git a/deps/lua/src/strbuf.h b/deps/lua/src/strbuf.h
new file mode 100644
index 000000000..f856543ad
--- /dev/null
+++ b/deps/lua/src/strbuf.h
@@ -0,0 +1,142 @@
+/* strbuf - String buffer routines
+ *
+ * Copyright (c) 2010-2011  Mark Pulford <mark@kyne.com.au>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <stdarg.h>
+
+/* Size: Total bytes allocated to *buf
+ * Length: String length, excluding optional NULL terminator.
+ * Increment: Allocation increments when resizing the string buffer.
+ * Dynamic: True if created via strbuf_new()
+ */
+
+typedef struct {
+    char *buf;
+    int size;
+    int length;
+    int increment;
+    int dynamic;
+    int reallocs;
+    int debug;
+} strbuf_t;
+
+#ifndef STRBUF_DEFAULT_SIZE
+#define STRBUF_DEFAULT_SIZE 1023
+#endif
+#ifndef STRBUF_DEFAULT_INCREMENT
+#define STRBUF_DEFAULT_INCREMENT -2
+#endif
+
+/* Initialise */
+extern strbuf_t *strbuf_new(int len);
+extern void strbuf_init(strbuf_t *s, int len);
+extern void strbuf_set_increment(strbuf_t *s, int increment);
+
+/* Release */
+extern void strbuf_free(strbuf_t *s);
+extern char *strbuf_free_to_string(strbuf_t *s, int *len);
+
+/* Management */
+extern void strbuf_resize(strbuf_t *s, int len);
+static int strbuf_empty_length(strbuf_t *s);
+static int strbuf_length(strbuf_t *s);
+static char *strbuf_string(strbuf_t *s, int *len);
+static  void strbuf_ensure_empty_length(strbuf_t *s, int len);
+
+/* Update */
+extern void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...);
+extern void strbuf_append_fmt_retry(strbuf_t *s, const char *format, ...);
+static void strbuf_append_mem(strbuf_t *s, const char *c, int len);
+extern void strbuf_append_string(strbuf_t *s, const char *str);
+static void strbuf_append_char(strbuf_t *s, const char c);
+static void strbuf_ensure_null(strbuf_t *s);
+
+/* Reset string for before use */
+static inline void strbuf_reset(strbuf_t *s)
+{
+    s->length = 0;
+}
+
+static inline int strbuf_allocated(strbuf_t *s)
+{
+    return s->buf != NULL;
+}
+
+/* Return bytes remaining in the string buffer
+ * Ensure there is space for a NULL terminator. */
+static inline int strbuf_empty_length(strbuf_t *s)
+{
+    return s->size - s->length - 1;
+}
+
+static inline void strbuf_ensure_empty_length(strbuf_t *s, int len)
+{
+    if (len > strbuf_empty_length(s))
+        strbuf_resize(s, s->length + len);
+}
+
+static inline int strbuf_length(strbuf_t *s)
+{
+    return s->length;
+}
+
+static inline void strbuf_append_char(strbuf_t *s, const char c)
+{
+    strbuf_ensure_empty_length(s, 1);
+    s->buf[s->length++] = c;
+}
+
+static inline void strbuf_append_char_unsafe(strbuf_t *s, const char c)
+{
+    s->buf[s->length++] = c;
+}
+
+static inline void strbuf_append_mem(strbuf_t *s, const char *c, int len)
+{
+    strbuf_ensure_empty_length(s, len);
+    memcpy(s->buf + s->length, c, len);
+    s->length += len;
+}
+
+static inline void strbuf_append_mem_unsafe(strbuf_t *s, const char *c, int len)
+{
+    memcpy(s->buf + s->length, c, len);
+    s->length += len;
+}
+
+static inline void strbuf_ensure_null(strbuf_t *s)
+{
+    s->buf[s->length] = 0;
+}
+
+static inline char *strbuf_string(strbuf_t *s, int *len)
+{
+    if (len)
+        *len = s->length;
+
+    return s->buf;
+}
+
+/* vi:ai et sw=4 ts=4:
+ */