[mirror_qemu.git] / qobject / qjson.c

/*
 * QObject JSON integration
 *
 * 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 "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qmp/json-parser.h"
#include "qapi/qmp/qjson.h"
#include "qapi/qmp/qbool.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qlist.h"
#include "qapi/qmp/qnum.h"
#include "qapi/qmp/qstring.h"
#include "qemu/unicode.h"

typedef struct JSONParsingState
{
    JSONMessageParser parser;
    QObject *result;
    Error *err;
} JSONParsingState;

static void consume_json(void *opaque, QObject *json, Error *err)
{
    JSONParsingState *s = opaque;

    assert(!json != !err);
    assert(!s->result || !s->err);

    if (s->result) {
        qobject_unref(s->result);
        s->result = NULL;
        error_setg(&s->err, "Expecting at most one JSON value");
    }
    if (s->err) {
        qobject_unref(json);
        error_free(err);
        return;
    }
    s->result = json;
    s->err = err;
}

/*
 * Parse @string as JSON value.
 * If @ap is non-null, interpolate %-escapes.
 * Takes ownership of %p arguments.
 * On success, return the JSON value.
 * On failure, store an error through @errp and return NULL.
 * Ownership of %p arguments becomes indeterminate then.  To avoid
 * leaks, callers passing %p must terminate on error, e.g. by passing
 * &error_abort.
 */
static QObject *qobject_from_jsonv(const char *string, va_list *ap,
                                   Error **errp)
{
    JSONParsingState state = {};

    json_message_parser_init(&state.parser, consume_json, &state, ap);
    json_message_parser_feed(&state.parser, string, strlen(string));
    json_message_parser_flush(&state.parser);
    json_message_parser_destroy(&state.parser);

    if (!state.result && !state.err) {
        error_setg(&state.err, "Expecting a JSON value");
    }

    error_propagate(errp, state.err);
    return state.result;
}

QObject *qobject_from_json(const char *string, Error **errp)
{
    return qobject_from_jsonv(string, NULL, errp);
}

/*
 * Parse @string as JSON value with %-escapes interpolated.
 * Abort on error.  Do not use with untrusted @string.
 * Return the resulting QObject.  It is never null.
 */
QObject *qobject_from_vjsonf_nofail(const char *string, va_list ap)
{
    va_list ap_copy;
    QObject *obj;

    /* va_copy() is needed when va_list is an array type */
    va_copy(ap_copy, ap);
    obj = qobject_from_jsonv(string, &ap_copy, &error_abort);
    va_end(ap_copy);

    assert(obj);
    return obj;
}

/*
 * Parse @string as JSON value with %-escapes interpolated.
 * Abort on error.  Do not use with untrusted @string.
 * Return the resulting QObject.  It is never null.
 */
QObject *qobject_from_jsonf_nofail(const char *string, ...)
{
    QObject *obj;
    va_list ap;

    va_start(ap, string);
    obj = qobject_from_vjsonf_nofail(string, ap);
    va_end(ap);

    return obj;
}

/*
 * Parse @string as JSON object with %-escapes interpolated.
 * Abort on error.  Do not use with untrusted @string.
 * Return the resulting QDict.  It is never null.
 */
QDict *qdict_from_vjsonf_nofail(const char *string, va_list ap)
{
    QDict *qdict;

    qdict = qobject_to(QDict, qobject_from_vjsonf_nofail(string, ap));
    assert(qdict);
    return qdict;
}

/*
 * Parse @string as JSON object with %-escapes interpolated.
 * Abort on error.  Do not use with untrusted @string.
 * Return the resulting QDict.  It is never null.
 */
QDict *qdict_from_jsonf_nofail(const char *string, ...)
{
    QDict *qdict;
    va_list ap;

    va_start(ap, string);
    qdict = qdict_from_vjsonf_nofail(string, ap);
    va_end(ap);
    return qdict;
}

typedef struct ToJsonIterState
{
    int indent;
    int pretty;
    int count;
    QString *str;
} ToJsonIterState;

static void to_json(const QObject *obj, QString *str, int pretty, int indent);

static void to_json_dict_iter(const char *key, QObject *obj, void *opaque)
{
    ToJsonIterState *s = opaque;
    QString *qkey;
    int j;

    if (s->count) {
        qstring_append(s->str, s->pretty ? "," : ", ");
    }

    if (s->pretty) {
        qstring_append(s->str, "\n");
        for (j = 0 ; j < s->indent ; j++)
            qstring_append(s->str, "    ");
    }

    qkey = qstring_from_str(key);
    to_json(QOBJECT(qkey), s->str, s->pretty, s->indent);
    qobject_unref(qkey);

    qstring_append(s->str, ": ");
    to_json(obj, s->str, s->pretty, s->indent);
    s->count++;
}

static void to_json_list_iter(QObject *obj, void *opaque)
{
    ToJsonIterState *s = opaque;
    int j;

    if (s->count) {
        qstring_append(s->str, s->pretty ? "," : ", ");
    }

    if (s->pretty) {
        qstring_append(s->str, "\n");
        for (j = 0 ; j < s->indent ; j++)
            qstring_append(s->str, "    ");
    }

    to_json(obj, s->str, s->pretty, s->indent);
    s->count++;
}

static void to_json(const QObject *obj, QString *str, int pretty, int indent)
{
    switch (qobject_type(obj)) {
    case QTYPE_QNULL:
        qstring_append(str, "null");
        break;
    case QTYPE_QNUM: {
        QNum *val = qobject_to(QNum, obj);
        char *buffer = qnum_to_string(val);
        qstring_append(str, buffer);
        g_free(buffer);
        break;
    }
    case QTYPE_QSTRING: {
        QString *val = qobject_to(QString, obj);
        const char *ptr;
        int cp;
        char buf[16];
        char *end;

        ptr = qstring_get_str(val);
        qstring_append(str, "\"");

        for (; *ptr; ptr = end) {
            cp = mod_utf8_codepoint(ptr, 6, &end);
            switch (cp) {
            case '\"':
                qstring_append(str, "\\\"");
                break;
            case '\\':
                qstring_append(str, "\\\\");
                break;
            case '\b':
                qstring_append(str, "\\b");
                break;
            case '\f':
                qstring_append(str, "\\f");
                break;
            case '\n':
                qstring_append(str, "\\n");
                break;
            case '\r':
                qstring_append(str, "\\r");
                break;
            case '\t':
                qstring_append(str, "\\t");
                break;
            default:
                if (cp < 0) {
                    cp = 0xFFFD; /* replacement character */
                }
                if (cp > 0xFFFF) {
                    /* beyond BMP; need a surrogate pair */
                    snprintf(buf, sizeof(buf), "\\u%04X\\u%04X",
                             0xD800 + ((cp - 0x10000) >> 10),
                             0xDC00 + ((cp - 0x10000) & 0x3FF));
                } else if (cp < 0x20 || cp >= 0x7F) {
                    snprintf(buf, sizeof(buf), "\\u%04X", cp);
                } else {
                    buf[0] = cp;
                    buf[1] = 0;
                }
                qstring_append(str, buf);
            }
        };

        qstring_append(str, "\"");
        break;
    }
    case QTYPE_QDICT: {
        ToJsonIterState s;
        QDict *val = qobject_to(QDict, obj);

        s.count = 0;
        s.str = str;
        s.indent = indent + 1;
        s.pretty = pretty;
        qstring_append(str, "{");
        qdict_iter(val, to_json_dict_iter, &s);
        if (pretty) {
            int j;
            qstring_append(str, "\n");
            for (j = 0 ; j < indent ; j++)
                qstring_append(str, "    ");
        }
        qstring_append(str, "}");
        break;
    }
    case QTYPE_QLIST: {
        ToJsonIterState s;
        QList *val = qobject_to(QList, obj);

        s.count = 0;
        s.str = str;
        s.indent = indent + 1;
        s.pretty = pretty;
        qstring_append(str, "[");
        qlist_iter(val, (void *)to_json_list_iter, &s);
        if (pretty) {
            int j;
            qstring_append(str, "\n");
            for (j = 0 ; j < indent ; j++)
                qstring_append(str, "    ");
        }
        qstring_append(str, "]");
        break;
    }
    case QTYPE_QBOOL: {
        QBool *val = qobject_to(QBool, obj);

        if (qbool_get_bool(val)) {
            qstring_append(str, "true");
        } else {
            qstring_append(str, "false");
        }
        break;
    }
    default:
        abort();
    }
}

QString *qobject_to_json(const QObject *obj)
{
    QString *str = qstring_new();

    to_json(obj, str, 0, 0);

    return str;
}

QString *qobject_to_json_pretty(const QObject *obj)
{
    QString *str = qstring_new();

    to_json(obj, str, 1, 0);

    return str;
}
Commit	Line	Data
b4748b9b AL	1	/*
	2	* QObject JSON integration
	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
f2ad72b3	14	#include "qemu/osdep.h"
99dbfd1d	15	#include "qapi/error.h"
86cdf9ec	16	#include "qapi/qmp/json-parser.h"
7b1b5d19	17	#include "qapi/qmp/qjson.h"
6b673957	18	#include "qapi/qmp/qbool.h"
452fcdbc	19	#include "qapi/qmp/qdict.h"
47e6b297	20	#include "qapi/qmp/qlist.h"
15280c36	21	#include "qapi/qmp/qnum.h"
fc81fa1e	22	#include "qapi/qmp/qstring.h"
f348b6d1	23	#include "qemu/unicode.h"
b4748b9b AL	24
	25	typedef struct JSONParsingState
	26	{
	27	JSONMessageParser parser;
b4748b9b	28	QObject *result;
99dbfd1d	29	Error *err;
b4748b9b AL	30	} JSONParsingState;
b4748b9b AL	31
62815d85	32	static void consume_json(void opaque, QObject json, Error *err)
b4748b9b	33	{
62815d85	34	JSONParsingState *s = opaque;
99dbfd1d	35
2a4794ba MA	36	assert(!json != !err);
	37	assert(!s->result \|\| !s->err);
	38
	39	if (s->result) {
	40	qobject_unref(s->result);
	41	s->result = NULL;
	42	error_setg(&s->err, "Expecting at most one JSON value");
	43	}
	44	if (s->err) {
	45	qobject_unref(json);
	46	error_free(err);
	47	return;
	48	}
62815d85	49	s->result = json;
2a4794ba	50	s->err = err;
b4748b9b AL	51	}
b4748b9b AL	52
2d36e843 MA	53	/*
	54	* Parse @string as JSON value.
	55	* If @ap is non-null, interpolate %-escapes.
	56	* Takes ownership of %p arguments.
	57	* On success, return the JSON value.
	58	* On failure, store an error through @errp and return NULL.
	59	* Ownership of %p arguments becomes indeterminate then. To avoid
	60	* leaks, callers passing %p must terminate on error, e.g. by passing
	61	* &error_abort.
	62	*/
	63	static QObject qobject_from_jsonv(const char string, va_list *ap,
	64	Error **errp)
b4748b9b AL	65	{
	66	JSONParsingState state = {};
	67
62815d85	68	json_message_parser_init(&state.parser, consume_json, &state, ap);
b4748b9b AL	69	json_message_parser_feed(&state.parser, string, strlen(string));
	70	json_message_parser_flush(&state.parser);
	71	json_message_parser_destroy(&state.parser);
	72
dd98e848 MA	73	if (!state.result && !state.err) {
	74	error_setg(&state.err, "Expecting a JSON value");
	75	}
	76
99dbfd1d	77	error_propagate(errp, state.err);
b4748b9b AL	78	return state.result;
	79	}
	80
57348c2f	81	QObject qobject_from_json(const char string, Error **errp)
8ff5a7d3	82	{
57348c2f	83	return qobject_from_jsonv(string, NULL, errp);
8ff5a7d3 LC	84	}
8ff5a7d3 LC	85
4ff18468 MA	86	/*
	87	* Parse @string as JSON value with %-escapes interpolated.
	88	* Abort on error. Do not use with untrusted @string.
	89	* Return the resulting QObject. It is never null.
	90	*/
	91	QObject qobject_from_vjsonf_nofail(const char string, va_list ap)
	92	{
	93	va_list ap_copy;
	94	QObject *obj;
	95
	96	/* va_copy() is needed when va_list is an array type */
	97	va_copy(ap_copy, ap);
	98	obj = qobject_from_jsonv(string, &ap_copy, &error_abort);
	99	va_end(ap_copy);
	100
	101	assert(obj);
	102	return obj;
	103	}
	104
6ce80fd8 MA	105	/*
	106	* Parse @string as JSON value with %-escapes interpolated.
	107	* Abort on error. Do not use with untrusted @string.
	108	* Return the resulting QObject. It is never null.
	109	*/
	110	QObject qobject_from_jsonf_nofail(const char string, ...)
b4748b9b	111	{
8ff5a7d3	112	QObject *obj;
b4748b9b AL	113	va_list ap;
	114
	115	va_start(ap, string);
4ff18468	116	obj = qobject_from_vjsonf_nofail(string, ap);
b4748b9b AL	117	va_end(ap);
b4748b9b AL	118
8ff5a7d3	119	return obj;
b4748b9b	120	}
1fd825f7	121
4ff18468 MA	122	/*
	123	* Parse @string as JSON object with %-escapes interpolated.
	124	* Abort on error. Do not use with untrusted @string.
	125	* Return the resulting QDict. It is never null.
	126	*/
	127	QDict qdict_from_vjsonf_nofail(const char string, va_list ap)
	128	{
	129	QDict *qdict;
	130
	131	qdict = qobject_to(QDict, qobject_from_vjsonf_nofail(string, ap));
	132	assert(qdict);
	133	return qdict;
	134	}
	135
a193352f MA	136	/*
	137	* Parse @string as JSON object with %-escapes interpolated.
	138	* Abort on error. Do not use with untrusted @string.
	139	* Return the resulting QDict. It is never null.
	140	*/
	141	QDict qdict_from_jsonf_nofail(const char string, ...)
	142	{
4ff18468	143	QDict *qdict;
a193352f MA	144	va_list ap;
	145
	146	va_start(ap, string);
4ff18468	147	qdict = qdict_from_vjsonf_nofail(string, ap);
a193352f	148	va_end(ap);
4ff18468	149	return qdict;
a193352f MA	150	}
a193352f MA	151
1fd825f7 AL	152	typedef struct ToJsonIterState
1fd825f7 AL	153	{
212b6008 DB	154	int indent;
212b6008 DB	155	int pretty;
1fd825f7 AL	156	int count;
	157	QString *str;
	158	} ToJsonIterState;
	159
212b6008	160	static void to_json(const QObject obj, QString str, int pretty, int indent);
1fd825f7 AL	161
	162	static void to_json_dict_iter(const char key, QObject obj, void *opaque)
	163	{
	164	ToJsonIterState *s = opaque;
	165	QString *qkey;
212b6008	166	int j;
1fd825f7	167
4b58554a HR	168	if (s->count) {
	169	qstring_append(s->str, s->pretty ? "," : ", ");
	170	}
212b6008 DB	171
	172	if (s->pretty) {
	173	qstring_append(s->str, "\n");
	174	for (j = 0 ; j < s->indent ; j++)
	175	qstring_append(s->str, " ");
1fd825f7 AL	176	}
	177
	178	qkey = qstring_from_str(key);
212b6008	179	to_json(QOBJECT(qkey), s->str, s->pretty, s->indent);
cb3e7f08	180	qobject_unref(qkey);
1fd825f7 AL	181
1fd825f7 AL	182	qstring_append(s->str, ": ");
212b6008	183	to_json(obj, s->str, s->pretty, s->indent);
1fd825f7 AL	184	s->count++;
	185	}
	186
	187	static void to_json_list_iter(QObject obj, void opaque)
	188	{
	189	ToJsonIterState *s = opaque;
212b6008	190	int j;
1fd825f7	191
4b58554a HR	192	if (s->count) {
	193	qstring_append(s->str, s->pretty ? "," : ", ");
	194	}
212b6008 DB	195
	196	if (s->pretty) {
	197	qstring_append(s->str, "\n");
	198	for (j = 0 ; j < s->indent ; j++)
	199	qstring_append(s->str, " ");
1fd825f7 AL	200	}
1fd825f7 AL	201
212b6008	202	to_json(obj, s->str, s->pretty, s->indent);
1fd825f7 AL	203	s->count++;
	204	}
	205
212b6008	206	static void to_json(const QObject obj, QString str, int pretty, int indent)
1fd825f7 AL	207	{
1fd825f7 AL	208	switch (qobject_type(obj)) {
481b002c MA	209	case QTYPE_QNULL:
	210	qstring_append(str, "null");
	211	break;
01b2ffce	212	case QTYPE_QNUM: {
7dc847eb	213	QNum *val = qobject_to(QNum, obj);
01b2ffce	214	char *buffer = qnum_to_string(val);
1fd825f7	215	qstring_append(str, buffer);
01b2ffce	216	g_free(buffer);
1fd825f7 AL	217	break;
	218	}
	219	case QTYPE_QSTRING: {
7dc847eb	220	QString *val = qobject_to(QString, obj);
1fd825f7	221	const char *ptr;
e2ec3f97 MA	222	int cp;
	223	char buf[16];
	224	char *end;
1fd825f7 AL	225
	226	ptr = qstring_get_str(val);
	227	qstring_append(str, "\"");
e2ec3f97 MA	228
	229	for (; *ptr; ptr = end) {
	230	cp = mod_utf8_codepoint(ptr, 6, &end);
	231	switch (cp) {
	232	case '\"':
	233	qstring_append(str, "\\\"");
	234	break;
	235	case '\\':
	236	qstring_append(str, "\\\\");
	237	break;
	238	case '\b':
	239	qstring_append(str, "\\b");
	240	break;
	241	case '\f':
	242	qstring_append(str, "\\f");
	243	break;
	244	case '\n':
	245	qstring_append(str, "\\n");
	246	break;
	247	case '\r':
	248	qstring_append(str, "\\r");
	249	break;
	250	case '\t':
	251	qstring_append(str, "\\t");
	252	break;
	253	default:
	254	if (cp < 0) {
	255	cp = 0xFFFD; /* replacement character */
1fd825f7	256	}
e2ec3f97 MA	257	if (cp > 0xFFFF) {
	258	/* beyond BMP; need a surrogate pair */
	259	snprintf(buf, sizeof(buf), "\\u%04X\\u%04X",
	260	0xD800 + ((cp - 0x10000) >> 10),
	261	0xDC00 + ((cp - 0x10000) & 0x3FF));
	262	} else if (cp < 0x20 \|\| cp >= 0x7F) {
	263	snprintf(buf, sizeof(buf), "\\u%04X", cp);
	264	} else {
	265	buf[0] = cp;
	266	buf[1] = 0;
1fd825f7	267	}
e2ec3f97 MA	268	qstring_append(str, buf);
	269	}
	270	};
	271
1fd825f7 AL	272	qstring_append(str, "\"");
	273	break;
	274	}
	275	case QTYPE_QDICT: {
	276	ToJsonIterState s;
7dc847eb	277	QDict *val = qobject_to(QDict, obj);
1fd825f7 AL	278
	279	s.count = 0;
	280	s.str = str;
212b6008 DB	281	s.indent = indent + 1;
212b6008 DB	282	s.pretty = pretty;
1fd825f7 AL	283	qstring_append(str, "{");
1fd825f7 AL	284	qdict_iter(val, to_json_dict_iter, &s);
212b6008 DB	285	if (pretty) {
	286	int j;
	287	qstring_append(str, "\n");
	288	for (j = 0 ; j < indent ; j++)
	289	qstring_append(str, " ");
	290	}
1fd825f7 AL	291	qstring_append(str, "}");
	292	break;
	293	}
	294	case QTYPE_QLIST: {
	295	ToJsonIterState s;
7dc847eb	296	QList *val = qobject_to(QList, obj);
1fd825f7 AL	297
	298	s.count = 0;
	299	s.str = str;
212b6008 DB	300	s.indent = indent + 1;
212b6008 DB	301	s.pretty = pretty;
1fd825f7 AL	302	qstring_append(str, "[");
1fd825f7 AL	303	qlist_iter(val, (void *)to_json_list_iter, &s);
212b6008 DB	304	if (pretty) {
	305	int j;
	306	qstring_append(str, "\n");
	307	for (j = 0 ; j < indent ; j++)
	308	qstring_append(str, " ");
	309	}
1fd825f7 AL	310	qstring_append(str, "]");
	311	break;
	312	}
1fd825f7	313	case QTYPE_QBOOL: {
7dc847eb	314	QBool *val = qobject_to(QBool, obj);
1fd825f7	315
fc48ffc3	316	if (qbool_get_bool(val)) {
1fd825f7 AL	317	qstring_append(str, "true");
	318	} else {
	319	qstring_append(str, "false");
	320	}
	321	break;
	322	}
a7c31816	323	default:
69dd62df	324	abort();
1fd825f7 AL	325	}
	326	}
	327
	328	QString qobject_to_json(const QObject obj)
	329	{
	330	QString *str = qstring_new();
	331
212b6008 DB	332	to_json(obj, str, 0, 0);
	333
	334	return str;
	335	}
	336
	337	QString qobject_to_json_pretty(const QObject obj)
	338	{
	339	QString *str = qstring_new();
	340
	341	to_json(obj, str, 1, 0);
1fd825f7 AL	342
	343	return str;
	344	}