/*
* JSON lexer
*
* Copyright IBM, Corp. 2009
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qstring.h"
#include "qlist.h"
#include "qdict.h"
#include "qint.h"
#include "qemu-common.h"
#include "json-lexer.h"
/*
* \"([^\\\"]|(\\\"\\'\\\\\\/\\b\\f\\n\\r\\t\\u[0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F]))*\"
* '([^\\']|(\\\"\\'\\\\\\/\\b\\f\\n\\r\\t\\u[0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F]))*'
* 0|([1-9][0-9]*(.[0-9]+)?([eE]([-+])?[0-9]+))
* [{}\[\],:]
* [a-z]+
*
*/
#undef ERROR
enum json_lexer_state {
ERROR = 0,
IN_DONE_STRING,
IN_DQ_UCODE3,
IN_DQ_UCODE2,
IN_DQ_UCODE1,
IN_DQ_UCODE0,
IN_DQ_STRING_ESCAPE,
IN_DQ_STRING,
IN_SQ_UCODE3,
IN_SQ_UCODE2,
IN_SQ_UCODE1,
IN_SQ_UCODE0,
IN_SQ_STRING_ESCAPE,
IN_SQ_STRING,
IN_ZERO,
IN_DIGITS,
IN_DIGIT,
IN_EXP_E,
IN_MANTISSA,
IN_MANTISSA_DIGITS,
IN_NONZERO_NUMBER,
IN_NEG_NONZERO_NUMBER,
IN_KEYWORD,
IN_ESCAPE,
IN_ESCAPE_L,
IN_ESCAPE_LL,
IN_ESCAPE_I,
IN_ESCAPE_I6,
IN_ESCAPE_I64,
IN_ESCAPE_DONE,
IN_WHITESPACE,
IN_OPERATOR_DONE,
IN_START,
};
#define TERMINAL(state) [0 ... 0x7F] = (state)
static const uint8_t json_lexer[][256] = {
[IN_DONE_STRING] = {
TERMINAL(JSON_STRING),
},
/* double quote string */
[IN_DQ_UCODE3] = {
['0' ... '9'] = IN_DQ_STRING,
['a' ... 'f'] = IN_DQ_STRING,
['A' ... 'F'] = IN_DQ_STRING,
},
[IN_DQ_UCODE2] = {
['0' ... '9'] = IN_DQ_UCODE3,
['a' ... 'f'] = IN_DQ_UCODE3,
['A' ... 'F'] = IN_DQ_UCODE3,
},
[IN_DQ_UCODE1] = {
['0' ... '9'] = IN_DQ_UCODE2,
['a' ... 'f'] = IN_DQ_UCODE2,
['A' ... 'F'] = IN_DQ_UCODE2,
},
[IN_DQ_UCODE0] = {
['0' ... '9'] = IN_DQ_UCODE1,
['a' ... 'f'] = IN_DQ_UCODE1,
['A' ... 'F'] = IN_DQ_UCODE1,
},
[IN_DQ_STRING_ESCAPE] = {
['b'] = IN_DQ_STRING,
['f'] = IN_DQ_STRING,
['n'] = IN_DQ_STRING,
['r'] = IN_DQ_STRING,
['t'] = IN_DQ_STRING,
['\''] = IN_DQ_STRING,
['\"'] = IN_DQ_STRING,
['u'] = IN_DQ_UCODE0,
},
[IN_DQ_STRING] = {
[1 ... 0xFF] = IN_DQ_STRING,
['\\'] = IN_DQ_STRING_ESCAPE,
['"'] = IN_DONE_STRING,
},
/* single quote string */
[IN_SQ_UCODE3] = {
['0' ... '9'] = IN_SQ_STRING,
['a' ... 'f'] = IN_SQ_STRING,
['A' ... 'F'] = IN_SQ_STRING,
},
[IN_SQ_UCODE2] = {
['0' ... '9'] = IN_SQ_UCODE3,
['a' ... 'f'] = IN_SQ_UCODE3,
['A' ... 'F'] = IN_SQ_UCODE3,
},
[IN_SQ_UCODE1] = {
['0' ... '9'] = IN_SQ_UCODE2,
['a' ... 'f'] = IN_SQ_UCODE2,
['A' ... 'F'] = IN_SQ_UCODE2,
},
[IN_SQ_UCODE0] = {
['0' ... '9'] = IN_SQ_UCODE1,
['a' ... 'f'] = IN_SQ_UCODE1,
['A' ... 'F'] = IN_SQ_UCODE1,
},
[IN_SQ_STRING_ESCAPE] = {
['b'] = IN_SQ_STRING,
['f'] = IN_SQ_STRING,
['n'] = IN_SQ_STRING,
['r'] = IN_SQ_STRING,
['t'] = IN_SQ_STRING,
['\''] = IN_SQ_STRING,
['\"'] = IN_SQ_STRING,
['u'] = IN_SQ_UCODE0,
},
[IN_SQ_STRING] = {
[1 ... 0xFF] = IN_SQ_STRING,
['\\'] = IN_SQ_STRING_ESCAPE,
['\''] = IN_DONE_STRING,
},
/* Zero */
[IN_ZERO] = {
TERMINAL(JSON_INTEGER),
['0' ... '9'] = ERROR,
['.'] = IN_MANTISSA,
},
/* Float */
[IN_DIGITS] = {
TERMINAL(JSON_FLOAT),
['0' ... '9'] = IN_DIGITS,
},
[IN_DIGIT] = {
['0' ... '9'] = IN_DIGITS,
},
[IN_EXP_E] = {
['-'] = IN_DIGIT,
['+'] = IN_DIGIT,
['0' ... '9'] = IN_DIGITS,
},
[IN_MANTISSA_DIGITS] = {
TERMINAL(JSON_FLOAT),
['0' ... '9'] = IN_MANTISSA_DIGITS,
['e'] = IN_EXP_E,
['E'] = IN_EXP_E,
},
[IN_MANTISSA] = {
['0' ... '9'] = IN_MANTISSA_DIGITS,
},
/* Number */
[IN_NONZERO_NUMBER] = {
TERMINAL(JSON_INTEGER),
['0' ... '9'] = IN_NONZERO_NUMBER,
['e'] = IN_EXP_E,
['E'] = IN_EXP_E,
['.'] = IN_MANTISSA,
},
[IN_NEG_NONZERO_NUMBER] = {
['0'] = IN_ZERO,
['1' ... '9'] = IN_NONZERO_NUMBER,
},
/* keywords */
[IN_KEYWORD] = {
TERMINAL(JSON_KEYWORD),
['a' ... 'z'] = IN_KEYWORD,
},
/* whitespace */
[IN_WHITESPACE] = {
TERMINAL(JSON_SKIP),
[' '] = IN_WHITESPACE,
['\t'] = IN_WHITESPACE,
['\r'] = IN_WHITESPACE,
['\n'] = IN_WHITESPACE,
},
/* operator */
[IN_OPERATOR_DONE] = {
TERMINAL(JSON_OPERATOR),
},
/* escape */
[IN_ESCAPE_DONE] = {
TERMINAL(JSON_ESCAPE),
},
[IN_ESCAPE_LL] = {
['d'] = IN_ESCAPE_DONE,
},
[IN_ESCAPE_L] = {
['d'] = IN_ESCAPE_DONE,
['l'] = IN_ESCAPE_LL,
},
[IN_ESCAPE_I64] = {
['d'] = IN_ESCAPE_DONE,
},
[IN_ESCAPE_I6] = {
['4'] = IN_ESCAPE_I64,
},
[IN_ESCAPE_I] = {
['6'] = IN_ESCAPE_I6,
},
[IN_ESCAPE] = {
['d'] = IN_ESCAPE_DONE,
['i'] = IN_ESCAPE_DONE,
['p'] = IN_ESCAPE_DONE,
['s'] = IN_ESCAPE_DONE,
['f'] = IN_ESCAPE_DONE,
['l'] = IN_ESCAPE_L,
['I'] = IN_ESCAPE_I,
},
/* top level rule */
[IN_START] = {
['"'] = IN_DQ_STRING,
['\''] = IN_SQ_STRING,
['0'] = IN_ZERO,
['1' ... '9'] = IN_NONZERO_NUMBER,
['-'] = IN_NEG_NONZERO_NUMBER,
['{'] = IN_OPERATOR_DONE,
['}'] = IN_OPERATOR_DONE,
['['] = IN_OPERATOR_DONE,
[']'] = IN_OPERATOR_DONE,
[','] = IN_OPERATOR_DONE,
[':'] = IN_OPERATOR_DONE,
['a' ... 'z'] = IN_KEYWORD,
['%'] = IN_ESCAPE,
[' '] = IN_WHITESPACE,
['\t'] = IN_WHITESPACE,
['\r'] = IN_WHITESPACE,
['\n'] = IN_WHITESPACE,
},
};
void json_lexer_init(JSONLexer *lexer, JSONLexerEmitter func)
{
lexer->emit = func;
lexer->state = IN_START;
lexer->token = qstring_new();
}
static int json_lexer_feed_char(JSONLexer *lexer, char ch)
{
char buf[2];
lexer->x++;
if (ch == '\n') {
lexer->x = 0;
lexer->y++;
}
lexer->state = json_lexer[lexer->state][(uint8_t)ch];
switch (lexer->state) {
case JSON_OPERATOR:
case JSON_ESCAPE:
case JSON_INTEGER:
case JSON_FLOAT:
case JSON_KEYWORD:
case JSON_STRING:
lexer->emit(lexer, lexer->token, lexer->state, lexer->x, lexer->y);
case JSON_SKIP:
lexer->state = json_lexer[IN_START][(uint8_t)ch];
QDECREF(lexer->token);
lexer->token = qstring_new();
break;
case ERROR:
return -EINVAL;
default:
break;
}
buf[0] = ch;
buf[1] = 0;
qstring_append(lexer->token, buf);
return 0;
}
int json_lexer_feed(JSONLexer *lexer, const char *buffer, size_t size)
{
size_t i;
for (i = 0; i < size; i++) {
int err;
err = json_lexer_feed_char(lexer, buffer[i]);
if (err < 0) {
return err;
}
}
return 0;
}
int json_lexer_flush(JSONLexer *lexer)
{
return json_lexer_feed_char(lexer, 0);
}
void json_lexer_destroy(JSONLexer *lexer)
{
QDECREF(lexer->token);
}