[qemu.git] / json-parser.c

/*
 * JSON Parser 
 *
 * 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 <stdbool.h>

#include "qemu-common.h"
#include "qstring.h"
#include "qint.h"
#include "qdict.h"
#include "qlist.h"
#include "qfloat.h"
#include "qbool.h"
#include "json-parser.h"
#include "json-lexer.h"

typedef struct JSONParserContext
{
} JSONParserContext;

#define BUG_ON(cond) assert(!(cond))

/**
 * TODO
 *
 * 0) make errors meaningful again
 * 1) add geometry information to tokens
 * 3) should we return a parsed size?
 * 4) deal with premature EOI
 */

static QObject *parse_value(JSONParserContext *ctxt, QList **tokens, va_list *ap);

/**
 * Token manipulators
 *
 * tokens are dictionaries that contain a type, a string value, and geometry information
 * about a token identified by the lexer.  These are routines that make working with
 * these objects a bit easier.
 */
static const char *token_get_value(QObject *obj)
{
    return qdict_get_str(qobject_to_qdict(obj), "token");
}

static JSONTokenType token_get_type(QObject *obj)
{
    return qdict_get_int(qobject_to_qdict(obj), "type");
}

static int token_is_operator(QObject *obj, char op)
{
    const char *val;

    if (token_get_type(obj) != JSON_OPERATOR) {
        return 0;
    }

    val = token_get_value(obj);

    return (val[0] == op) && (val[1] == 0);
}

static int token_is_keyword(QObject *obj, const char *value)
{
    if (token_get_type(obj) != JSON_KEYWORD) {
        return 0;
    }

    return strcmp(token_get_value(obj), value) == 0;
}

static int token_is_escape(QObject *obj, const char *value)
{
    if (token_get_type(obj) != JSON_ESCAPE) {
        return 0;
    }

    return (strcmp(token_get_value(obj), value) == 0);
}

/**
 * Error handler
 */
static void parse_error(JSONParserContext *ctxt, QObject *token, const char *msg, ...)
{
    fprintf(stderr, "parse error: %s\n", msg);
}

/**
 * String helpers
 *
 * These helpers are used to unescape strings.
 */
static void wchar_to_utf8(uint16_t wchar, char *buffer, size_t buffer_length)
{
    if (wchar <= 0x007F) {
        BUG_ON(buffer_length < 2);

        buffer[0] = wchar & 0x7F;
        buffer[1] = 0;
    } else if (wchar <= 0x07FF) {
        BUG_ON(buffer_length < 3);

        buffer[0] = 0xC0 | ((wchar >> 6) & 0x1F);
        buffer[1] = 0x80 | (wchar & 0x3F);
        buffer[2] = 0;
    } else {
        BUG_ON(buffer_length < 4);

        buffer[0] = 0xE0 | ((wchar >> 12) & 0x0F);
        buffer[1] = 0x80 | ((wchar >> 6) & 0x3F);
        buffer[2] = 0x80 | (wchar & 0x3F);
        buffer[3] = 0;
    }
}

static int hex2decimal(char ch)
{
    if (ch >= '0' && ch <= '9') {
        return (ch - '0');
    } else if (ch >= 'a' && ch <= 'f') {
        return 10 + (ch - 'a');
    } else if (ch >= 'A' && ch <= 'F') {
        return 10 + (ch - 'A');
    }

    return -1;
}

/**
 * parse_string(): Parse a json string and return a QObject
 *
 *  string
 *      ""
 *      " chars "
 *  chars
 *      char
 *      char chars
 *  char
 *      any-Unicode-character-
 *          except-"-or-\-or-
 *          control-character
 *      \"
 *      \\
 *      \/
 *      \b
 *      \f
 *      \n
 *      \r
 *      \t
 *      \u four-hex-digits 
 */
static QString *qstring_from_escaped_str(JSONParserContext *ctxt, QObject *token)
{
    const char *ptr = token_get_value(token);
    QString *str;
    int double_quote = 1;

    if (*ptr == '"') {
        double_quote = 1;
    } else {
        double_quote = 0;
    }
    ptr++;

    str = qstring_new();
    while (*ptr && 
           ((double_quote && *ptr != '"') || (!double_quote && *ptr != '\''))) {
        if (*ptr == '\\') {
            ptr++;

            switch (*ptr) {
            case '"':
                qstring_append(str, "\"");
                ptr++;
                break;
            case '\'':
                qstring_append(str, "'");
                ptr++;
                break;
            case '\\':
                qstring_append(str, "\\");
                ptr++;
                break;
            case '/':
                qstring_append(str, "/");
                ptr++;
                break;
            case 'b':
                qstring_append(str, "\b");
                ptr++;
                break;
            case 'n':
                qstring_append(str, "\n");
                ptr++;
                break;
            case 'r':
                qstring_append(str, "\r");
                ptr++;
                break;
            case 't':
                qstring_append(str, "\t");
                ptr++;
                break;
            case 'u': {
                uint16_t unicode_char = 0;
                char utf8_char[4];
                int i = 0;

                ptr++;

                for (i = 0; i < 4; i++) {
                    if (qemu_isxdigit(*ptr)) {
                        unicode_char |= hex2decimal(*ptr) << ((3 - i) * 4);
                    } else {
                        parse_error(ctxt, token,
                                    "invalid hex escape sequence in string");
                        goto out;
                    }
                    ptr++;
                }

                wchar_to_utf8(unicode_char, utf8_char, sizeof(utf8_char));
                qstring_append(str, utf8_char);
            }   break;
            default:
                parse_error(ctxt, token, "invalid escape sequence in string");
                goto out;
            }
        } else {
            char dummy[2];

            dummy[0] = *ptr++;
            dummy[1] = 0;

            qstring_append(str, dummy);
        }
    }

    return str;

out:
    QDECREF(str);
    return NULL;
}

/**
 * Parsing rules
 */
static int parse_pair(JSONParserContext *ctxt, QDict *dict, QList **tokens, va_list *ap)
{
    QObject *key, *token = NULL, *value, *peek;
    QList *working = qlist_copy(*tokens);

    peek = qlist_peek(working);
    key = parse_value(ctxt, &working, ap);
    if (qobject_type(key) != QTYPE_QSTRING) {
        parse_error(ctxt, peek, "key is not a string in object");
        goto out;
    }

    token = qlist_pop(working);
    if (!token_is_operator(token, ':')) {
        parse_error(ctxt, token, "missing : in object pair");
        goto out;
    }

    value = parse_value(ctxt, &working, ap);
    if (value == NULL) {
        parse_error(ctxt, token, "Missing value in dict");
        goto out;
    }

    qdict_put_obj(dict, qstring_get_str(qobject_to_qstring(key)), value);

    qobject_decref(token);
    qobject_decref(key);
    QDECREF(*tokens);
    *tokens = working;

    return 0;

out:
    qobject_decref(token);
    qobject_decref(key);
    QDECREF(working);

    return -1;
}

static QObject *parse_object(JSONParserContext *ctxt, QList **tokens, va_list *ap)
{
    QDict *dict = NULL;
    QObject *token, *peek;
    QList *working = qlist_copy(*tokens);

    token = qlist_pop(working);
    if (!token_is_operator(token, '{')) {
        goto out;
    }
    qobject_decref(token);
    token = NULL;

    dict = qdict_new();

    peek = qlist_peek(working);
    if (!token_is_operator(peek, '}')) {
        if (parse_pair(ctxt, dict, &working, ap) == -1) {
            goto out;
        }

        token = qlist_pop(working);
        while (!token_is_operator(token, '}')) {
            if (!token_is_operator(token, ',')) {
                parse_error(ctxt, token, "expected separator in dict");
                goto out;
            }
            qobject_decref(token);
            token = NULL;

            if (parse_pair(ctxt, dict, &working, ap) == -1) {
                goto out;
            }

            token = qlist_pop(working);
        }
        qobject_decref(token);
        token = NULL;
    } else {
        token = qlist_pop(working);
        qobject_decref(token);
        token = NULL;
    }

    QDECREF(*tokens);
    *tokens = working;

    return QOBJECT(dict);

out:
    qobject_decref(token);
    QDECREF(working);
    QDECREF(dict);
    return NULL;
}

static QObject *parse_array(JSONParserContext *ctxt, QList **tokens, va_list *ap)
{
    QList *list = NULL;
    QObject *token, *peek;
    QList *working = qlist_copy(*tokens);

    token = qlist_pop(working);
    if (!token_is_operator(token, '[')) {
        goto out;
    }
    qobject_decref(token);
    token = NULL;

    list = qlist_new();

    peek = qlist_peek(working);
    if (!token_is_operator(peek, ']')) {
        QObject *obj;

        obj = parse_value(ctxt, &working, ap);
        if (obj == NULL) {
            parse_error(ctxt, token, "expecting value");
            goto out;
        }

        qlist_append_obj(list, obj);

        token = qlist_pop(working);
        while (!token_is_operator(token, ']')) {
            if (!token_is_operator(token, ',')) {
                parse_error(ctxt, token, "expected separator in list");
                goto out;
            }

            qobject_decref(token);
            token = NULL;

            obj = parse_value(ctxt, &working, ap);
            if (obj == NULL) {
                parse_error(ctxt, token, "expecting value");
                goto out;
            }

            qlist_append_obj(list, obj);

            token = qlist_pop(working);
        }

        qobject_decref(token);
        token = NULL;
    } else {
        token = qlist_pop(working);
        qobject_decref(token);
        token = NULL;
    }

    QDECREF(*tokens);
    *tokens = working;

    return QOBJECT(list);

out:
    qobject_decref(token);
    QDECREF(working);
    QDECREF(list);
    return NULL;
}

static QObject *parse_keyword(JSONParserContext *ctxt, QList **tokens)
{
    QObject *token, *ret;
    QList *working = qlist_copy(*tokens);

    token = qlist_pop(working);

    if (token_get_type(token) != JSON_KEYWORD) {
        goto out;
    }

    if (token_is_keyword(token, "true")) {
        ret = QOBJECT(qbool_from_int(true));
    } else if (token_is_keyword(token, "false")) {
        ret = QOBJECT(qbool_from_int(false));
    } else {
        parse_error(ctxt, token, "invalid keyword `%s'", token_get_value(token));
        goto out;
    }

    qobject_decref(token);
    QDECREF(*tokens);
    *tokens = working;

    return ret;

out: 
    qobject_decref(token);
    QDECREF(working);

    return NULL;
}

static QObject *parse_escape(JSONParserContext *ctxt, QList **tokens, va_list *ap)
{
    QObject *token = NULL, *obj;
    QList *working = qlist_copy(*tokens);

    if (ap == NULL) {
        goto out;
    }

    token = qlist_pop(working);

    if (token_is_escape(token, "%p")) {
        obj = va_arg(*ap, QObject *);
    } else if (token_is_escape(token, "%i")) {
        obj = QOBJECT(qbool_from_int(va_arg(*ap, int)));
    } else if (token_is_escape(token, "%d")) {
        obj = QOBJECT(qint_from_int(va_arg(*ap, int)));
    } else if (token_is_escape(token, "%ld")) {
        obj = QOBJECT(qint_from_int(va_arg(*ap, long)));
    } else if (token_is_escape(token, "%lld")) {
        obj = QOBJECT(qint_from_int(va_arg(*ap, long long)));
    } else if (token_is_escape(token, "%s")) {
        obj = QOBJECT(qstring_from_str(va_arg(*ap, const char *)));
    } else if (token_is_escape(token, "%f")) {
        obj = QOBJECT(qfloat_from_double(va_arg(*ap, double)));
    } else {
        goto out;
    }

    qobject_decref(token);
    QDECREF(*tokens);
    *tokens = working;

    return obj;

out:
    qobject_decref(token);
    QDECREF(working);

    return NULL;
}

static QObject *parse_literal(JSONParserContext *ctxt, QList **tokens)
{
    QObject *token, *obj;
    QList *working = qlist_copy(*tokens);

    token = qlist_pop(working);
    switch (token_get_type(token)) {
    case JSON_STRING:
        obj = QOBJECT(qstring_from_escaped_str(ctxt, token));
        break;
    case JSON_INTEGER:
        obj = QOBJECT(qint_from_int(strtoll(token_get_value(token), NULL, 10)));
        break;
    case JSON_FLOAT:
        /* FIXME dependent on locale */
        obj = QOBJECT(qfloat_from_double(strtod(token_get_value(token), NULL)));
        break;
    default:
        goto out;
    }

    qobject_decref(token);
    QDECREF(*tokens);
    *tokens = working;

    return obj;

out:
    qobject_decref(token);
    QDECREF(working);

    return NULL;
}

static QObject *parse_value(JSONParserContext *ctxt, QList **tokens, va_list *ap)
{
    QObject *obj;

    obj = parse_object(ctxt, tokens, ap);
    if (obj == NULL) {
        obj = parse_array(ctxt, tokens, ap);
    }
    if (obj == NULL) {
        obj = parse_escape(ctxt, tokens, ap);
    }
    if (obj == NULL) {
        obj = parse_keyword(ctxt, tokens);
    } 
    if (obj == NULL) {
        obj = parse_literal(ctxt, tokens);
    }

    return obj;
}

QObject *json_parser_parse(QList *tokens, va_list *ap)
{
    JSONParserContext ctxt = {};
    QList *working = qlist_copy(tokens);
    QObject *result;

    result = parse_value(&ctxt, &working, ap);

    QDECREF(working);

    return result;
}
Commit	Line	Data
4a5fcab7 AL	1	/*
	2	* JSON Parser
	3	*
	4	* Copyright IBM, Corp. 2009
	5	*
	6	* Authors:
	7	* Anthony Liguori <aliguori@us.ibm.com>
	8	*
	9	* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
	10	* See the COPYING.LIB file in the top-level directory.
	11	*
	12	*/
	13
	14	#include <stdbool.h>
	15
	16	#include "qemu-common.h"
	17	#include "qstring.h"
	18	#include "qint.h"
	19	#include "qdict.h"
	20	#include "qlist.h"
	21	#include "qfloat.h"
	22	#include "qbool.h"
	23	#include "json-parser.h"
	24	#include "json-lexer.h"
	25
	26	typedef struct JSONParserContext
	27	{
	28	} JSONParserContext;
	29
	30	#define BUG_ON(cond) assert(!(cond))
	31
	32	/**
	33	* TODO
	34	*
	35	* 0) make errors meaningful again
	36	* 1) add geometry information to tokens
	37	* 3) should we return a parsed size?
	38	* 4) deal with premature EOI
	39	*/
	40
	41	static QObject parse_value(JSONParserContext ctxt, QList *tokens, va_list ap);
	42
	43	/**
	44	* Token manipulators
	45	*
	46	* tokens are dictionaries that contain a type, a string value, and geometry information
	47	* about a token identified by the lexer. These are routines that make working with
	48	* these objects a bit easier.
	49	*/
	50	static const char token_get_value(QObject obj)
	51	{
	52	return qdict_get_str(qobject_to_qdict(obj), "token");
	53	}
	54
	55	static JSONTokenType token_get_type(QObject *obj)
	56	{
	57	return qdict_get_int(qobject_to_qdict(obj), "type");
	58	}
	59
	60	static int token_is_operator(QObject *obj, char op)
	61	{
	62	const char *val;
	63
	64	if (token_get_type(obj) != JSON_OPERATOR) {
65	return 0;
66	}
67
68	val = token_get_value(obj);
69
70	return (val[0] == op) && (val[1] == 0);
71	}
72
73	static int token_is_keyword(QObject obj, const char value)
74	{
75	if (token_get_type(obj) != JSON_KEYWORD) {
76	return 0;
77	}
78
79	return strcmp(token_get_value(obj), value) == 0;
80	}
81
82	static int token_is_escape(QObject obj, const char value)
83	{
84	if (token_get_type(obj) != JSON_ESCAPE) {
85	return 0;
86	}
87
88	return (strcmp(token_get_value(obj), value) == 0);
89	}
90
91	/**
92	* Error handler
93	*/
94	static void parse_error(JSONParserContext ctxt, QObject token, const char *msg, ...)
95	{
96	fprintf(stderr, "parse error: %s\n", msg);
97	}
98
99	/**
100	* String helpers
101	*
102	* These helpers are used to unescape strings.
103	*/
104	static void wchar_to_utf8(uint16_t wchar, char *buffer, size_t buffer_length)
105	{
106	if (wchar <= 0x007F) {
107	BUG_ON(buffer_length < 2);
108
109	buffer[0] = wchar & 0x7F;
110	buffer[1] = 0;
111	} else if (wchar <= 0x07FF) {
112	BUG_ON(buffer_length < 3);
113
114	buffer[0] = 0xC0 \| ((wchar >> 6) & 0x1F);
115	buffer[1] = 0x80 \| (wchar & 0x3F);
116	buffer[2] = 0;
117	} else {
118	BUG_ON(buffer_length < 4);
119
120	buffer[0] = 0xE0 \| ((wchar >> 12) & 0x0F);
121	buffer[1] = 0x80 \| ((wchar >> 6) & 0x3F);
122	buffer[2] = 0x80 \| (wchar & 0x3F);
123	buffer[3] = 0;
124	}
125	}
126
127	static int hex2decimal(char ch)
128	{
129	if (ch >= '0' && ch <= '9') {
130	return (ch - '0');
131	} else if (ch >= 'a' && ch <= 'f') {
132	return 10 + (ch - 'a');
133	} else if (ch >= 'A' && ch <= 'F') {
134	return 10 + (ch - 'A');
135	}
136
137	return -1;
138	}
139
140	/**
141	* parse_string(): Parse a json string and return a QObject
142	*
143	* string
144	* ""
145	* " chars "
146	* chars
147	* char
148	* char chars
149	* char
150	* any-Unicode-character-
151	* except-"-or-\-or-
152	* control-character
153	* \"
154	* \\
155	* \/
156	* \b
157	* \f
158	* \n
159	* \r
160	* \t
161	* \u four-hex-digits
162	*/
163	static QString qstring_from_escaped_str(JSONParserContext ctxt, QObject *token)
164	{
165	const char *ptr = token_get_value(token);
166	QString *str;
167	int double_quote = 1;
168
169	if (*ptr == '"') {
170	double_quote = 1;
171	} else {
172	double_quote = 0;
173	}
174	ptr++;
175
176	str = qstring_new();
177	while (*ptr &&
178	((double_quote && ptr != '"') \|\| (!double_quote && ptr != '\''))) {
179	if (*ptr == '\\') {
180	ptr++;
181
182	switch (*ptr) {
183	case '"':
184	qstring_append(str, "\"");
185	ptr++;
186	break;
187	case '\'':
188	qstring_append(str, "'");
189	ptr++;
190	break;
191	case '\\':
192	qstring_append(str, "\\");
193	ptr++;
194	break;
195	case '/':
196	qstring_append(str, "/");
197	ptr++;
198	break;
199	case 'b':
200	qstring_append(str, "\b");
201	ptr++;
202	break;
203	case 'n':
204	qstring_append(str, "\n");
205	ptr++;
206	break;
207	case 'r':
208	qstring_append(str, "\r");
209	ptr++;
210	break;
211	case 't':
212	qstring_append(str, "\t");
213	ptr++;
214	break;
215	case 'u': {
216	uint16_t unicode_char = 0;
217	char utf8_char[4];
218	int i = 0;
219
220	ptr++;
221
222	for (i = 0; i < 4; i++) {
223	if (qemu_isxdigit(*ptr)) {
224	unicode_char \|= hex2decimal(ptr) << ((3 - i) 4);
225	} else {
226	parse_error(ctxt, token,
227	"invalid hex escape sequence in string");
228	goto out;
229	}
230	ptr++;
231	}
232
233	wchar_to_utf8(unicode_char, utf8_char, sizeof(utf8_char));
234	qstring_append(str, utf8_char);
235	} break;
236	default:
237	parse_error(ctxt, token, "invalid escape sequence in string");
238	goto out;
239	}
240	} else {
241	char dummy[2];
242
243	dummy[0] = *ptr++;
244	dummy[1] = 0;
245
246	qstring_append(str, dummy);
247	}
248	}
249
4a5fcab7 AL	250	return str;
	251
	252	out:
	253	QDECREF(str);
	254	return NULL;
	255	}
	256
	257	/**
	258	* Parsing rules
	259	*/
	260	static int parse_pair(JSONParserContext ctxt, QDict dict, QList *tokens, va_list ap)
	261	{
	262	QObject key, token = NULL, value, peek;
	263	QList working = qlist_copy(tokens);
	264
	265	peek = qlist_peek(working);
	266	key = parse_value(ctxt, &working, ap);
	267	if (qobject_type(key) != QTYPE_QSTRING) {
	268	parse_error(ctxt, peek, "key is not a string in object");
	269	goto out;
	270	}
	271
	272	token = qlist_pop(working);
	273	if (!token_is_operator(token, ':')) {
	274	parse_error(ctxt, token, "missing : in object pair");
	275	goto out;
	276	}
	277
	278	value = parse_value(ctxt, &working, ap);
	279	if (value == NULL) {
	280	parse_error(ctxt, token, "Missing value in dict");
	281	goto out;
	282	}
	283
	284	qdict_put_obj(dict, qstring_get_str(qobject_to_qstring(key)), value);
	285
	286	qobject_decref(token);
	287	qobject_decref(key);
	288	QDECREF(*tokens);
	289	*tokens = working;
	290
	291	return 0;
	292
	293	out:
	294	qobject_decref(token);
	295	qobject_decref(key);
	296	QDECREF(working);
	297
	298	return -1;
	299	}
	300
	301	static QObject parse_object(JSONParserContext ctxt, QList *tokens, va_list ap)
	302	{
	303	QDict *dict = NULL;
	304	QObject token, peek;
	305	QList working = qlist_copy(tokens);
	306
	307	token = qlist_pop(working);
	308	if (!token_is_operator(token, '{')) {
	309	goto out;
	310	}
	311	qobject_decref(token);
	312	token = NULL;
	313
314	dict = qdict_new();
315
316	peek = qlist_peek(working);
317	if (!token_is_operator(peek, '}')) {
318	if (parse_pair(ctxt, dict, &working, ap) == -1) {
319	goto out;
320	}
321
322	token = qlist_pop(working);
323	while (!token_is_operator(token, '}')) {
324	if (!token_is_operator(token, ',')) {
325	parse_error(ctxt, token, "expected separator in dict");
326	goto out;
327	}
328	qobject_decref(token);
329	token = NULL;
330
331	if (parse_pair(ctxt, dict, &working, ap) == -1) {
332	goto out;
333	}
334
335	token = qlist_pop(working);
336	}
337	qobject_decref(token);
338	token = NULL;
339	} else {
340	token = qlist_pop(working);
341	qobject_decref(token);
342	token = NULL;
343	}
344
345	QDECREF(*tokens);
346	*tokens = working;
347
348	return QOBJECT(dict);
349
350	out:
351	qobject_decref(token);
352	QDECREF(working);
353	QDECREF(dict);
354	return NULL;
355	}
356
357	static QObject parse_array(JSONParserContext ctxt, QList *tokens, va_list ap)
358	{
359	QList *list = NULL;
360	QObject token, peek;
361	QList working = qlist_copy(tokens);
362
363	token = qlist_pop(working);
364	if (!token_is_operator(token, '[')) {
365	goto out;
366	}
367	qobject_decref(token);
368	token = NULL;
369
370	list = qlist_new();
371
372	peek = qlist_peek(working);
373	if (!token_is_operator(peek, ']')) {
374	QObject *obj;
375
376	obj = parse_value(ctxt, &working, ap);
377	if (obj == NULL) {
378	parse_error(ctxt, token, "expecting value");
379	goto out;
380	}
381
382	qlist_append_obj(list, obj);
383
384	token = qlist_pop(working);
385	while (!token_is_operator(token, ']')) {
386	if (!token_is_operator(token, ',')) {
387	parse_error(ctxt, token, "expected separator in list");
388	goto out;
389	}
390
391	qobject_decref(token);
392	token = NULL;
393
394	obj = parse_value(ctxt, &working, ap);
395	if (obj == NULL) {
396	parse_error(ctxt, token, "expecting value");
397	goto out;
398	}
399
400	qlist_append_obj(list, obj);
401
402	token = qlist_pop(working);
403	}
404
405	qobject_decref(token);
406	token = NULL;
407	} else {
408	token = qlist_pop(working);
409	qobject_decref(token);
410	token = NULL;
411	}
412
413	QDECREF(*tokens);
414	*tokens = working;
415
416	return QOBJECT(list);
417
418	out:
419	qobject_decref(token);
420	QDECREF(working);
421	QDECREF(list);
422	return NULL;
423	}
424
425	static QObject parse_keyword(JSONParserContext ctxt, QList **tokens)
426	{
427	QObject token, ret;
428	QList working = qlist_copy(tokens);
429
430	token = qlist_pop(working);
431
432	if (token_get_type(token) != JSON_KEYWORD) {
433	goto out;
434	}
435
436	if (token_is_keyword(token, "true")) {
437	ret = QOBJECT(qbool_from_int(true));
438	} else if (token_is_keyword(token, "false")) {
439	ret = QOBJECT(qbool_from_int(false));
440	} else {
441	parse_error(ctxt, token, "invalid keyword `%s'", token_get_value(token));
442	goto out;
443	}
444
445	qobject_decref(token);
446	QDECREF(*tokens);
447	*tokens = working;
448
449	return ret;
450
451	out:
452	qobject_decref(token);
453	QDECREF(working);
454
455	return NULL;
456	}
457
458	static QObject parse_escape(JSONParserContext ctxt, QList *tokens, va_list ap)
459	{
460	QObject token = NULL, obj;
461	QList working = qlist_copy(tokens);
462
463	if (ap == NULL) {
464	goto out;
465	}
466
467	token = qlist_pop(working);
468
469	if (token_is_escape(token, "%p")) {
470	obj = va_arg(ap, QObject );
471	} else if (token_is_escape(token, "%i")) {
472	obj = QOBJECT(qbool_from_int(va_arg(*ap, int)));
473	} else if (token_is_escape(token, "%d")) {
474	obj = QOBJECT(qint_from_int(va_arg(*ap, int)));
475	} else if (token_is_escape(token, "%ld")) {
476	obj = QOBJECT(qint_from_int(va_arg(*ap, long)));
477	} else if (token_is_escape(token, "%lld")) {
478	obj = QOBJECT(qint_from_int(va_arg(*ap, long long)));
479	} else if (token_is_escape(token, "%s")) {
480	obj = QOBJECT(qstring_from_str(va_arg(ap, const char )));
481	} else if (token_is_escape(token, "%f")) {
482	obj = QOBJECT(qfloat_from_double(va_arg(*ap, double)));
483	} else {
484	goto out;
485	}
486
487	qobject_decref(token);
488	QDECREF(*tokens);
489	*tokens = working;
490
491	return obj;
492
493	out:
494	qobject_decref(token);
495	QDECREF(working);
496
497	return NULL;
498	}
499
500	static QObject parse_literal(JSONParserContext ctxt, QList **tokens)
501	{
502	QObject token, obj;
503	QList working = qlist_copy(tokens);
504
505	token = qlist_pop(working);
506	switch (token_get_type(token)) {
507	case JSON_STRING:
508	obj = QOBJECT(qstring_from_escaped_str(ctxt, token));
509	break;
510	case JSON_INTEGER:
511	obj = QOBJECT(qint_from_int(strtoll(token_get_value(token), NULL, 10)));
512	break;
513	case JSON_FLOAT:
514	/* FIXME dependent on locale */
515	obj = QOBJECT(qfloat_from_double(strtod(token_get_value(token), NULL)));
516	break;
517	default:
518	goto out;
519	}
520
521	qobject_decref(token);
522	QDECREF(*tokens);
523	*tokens = working;
524
525	return obj;
526
527	out:
528	qobject_decref(token);
529	QDECREF(working);
530
531	return NULL;
532	}
533
534	static QObject parse_value(JSONParserContext ctxt, QList *tokens, va_list ap)
535	{
536	QObject *obj;
537
538	obj = parse_object(ctxt, tokens, ap);
539	if (obj == NULL) {
540	obj = parse_array(ctxt, tokens, ap);
541	}
542	if (obj == NULL) {
543	obj = parse_escape(ctxt, tokens, ap);
544	}
545	if (obj == NULL) {
546	obj = parse_keyword(ctxt, tokens);
547	}
548	if (obj == NULL) {
549	obj = parse_literal(ctxt, tokens);
550	}
551
552	return obj;
553	}
554
555	QObject json_parser_parse(QList tokens, va_list *ap)
556	{
557	JSONParserContext ctxt = {};
558	QList *working = qlist_copy(tokens);
559	QObject *result;
560
561	result = parse_value(&ctxt, &working, ap);
562
563	QDECREF(working);
564
565	return result;
566	}