--- /dev/null
+#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:
+ */
projects / redis.git / commitdiff
