xref: /openbmc/qemu/qobject/qjson.c (revision 8917c3bd)
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 
14 #include "qapi/qmp/json-lexer.h"
15 #include "qapi/qmp/json-parser.h"
16 #include "qapi/qmp/json-streamer.h"
17 #include "qapi/qmp/qjson.h"
18 #include "qapi/qmp/qint.h"
19 #include "qapi/qmp/qlist.h"
20 #include "qapi/qmp/qbool.h"
21 #include "qapi/qmp/qfloat.h"
22 #include "qapi/qmp/qdict.h"
23 
24 typedef struct JSONParsingState
25 {
26     JSONMessageParser parser;
27     va_list *ap;
28     QObject *result;
29 } JSONParsingState;
30 
31 static void parse_json(JSONMessageParser *parser, QList *tokens)
32 {
33     JSONParsingState *s = container_of(parser, JSONParsingState, parser);
34     s->result = json_parser_parse(tokens, s->ap);
35 }
36 
37 QObject *qobject_from_jsonv(const char *string, va_list *ap)
38 {
39     JSONParsingState state = {};
40 
41     state.ap = ap;
42 
43     json_message_parser_init(&state.parser, parse_json);
44     json_message_parser_feed(&state.parser, string, strlen(string));
45     json_message_parser_flush(&state.parser);
46     json_message_parser_destroy(&state.parser);
47 
48     return state.result;
49 }
50 
51 QObject *qobject_from_json(const char *string)
52 {
53     return qobject_from_jsonv(string, NULL);
54 }
55 
56 /*
57  * IMPORTANT: This function aborts on error, thus it must not
58  * be used with untrusted arguments.
59  */
60 QObject *qobject_from_jsonf(const char *string, ...)
61 {
62     QObject *obj;
63     va_list ap;
64 
65     va_start(ap, string);
66     obj = qobject_from_jsonv(string, &ap);
67     va_end(ap);
68 
69     assert(obj != NULL);
70     return obj;
71 }
72 
73 typedef struct ToJsonIterState
74 {
75     int indent;
76     int pretty;
77     int count;
78     QString *str;
79 } ToJsonIterState;
80 
81 static void to_json(const QObject *obj, QString *str, int pretty, int indent);
82 
83 static void to_json_dict_iter(const char *key, QObject *obj, void *opaque)
84 {
85     ToJsonIterState *s = opaque;
86     QString *qkey;
87     int j;
88 
89     if (s->count)
90         qstring_append(s->str, ", ");
91 
92     if (s->pretty) {
93         qstring_append(s->str, "\n");
94         for (j = 0 ; j < s->indent ; j++)
95             qstring_append(s->str, "    ");
96     }
97 
98     qkey = qstring_from_str(key);
99     to_json(QOBJECT(qkey), s->str, s->pretty, s->indent);
100     QDECREF(qkey);
101 
102     qstring_append(s->str, ": ");
103     to_json(obj, s->str, s->pretty, s->indent);
104     s->count++;
105 }
106 
107 static void to_json_list_iter(QObject *obj, void *opaque)
108 {
109     ToJsonIterState *s = opaque;
110     int j;
111 
112     if (s->count)
113         qstring_append(s->str, ", ");
114 
115     if (s->pretty) {
116         qstring_append(s->str, "\n");
117         for (j = 0 ; j < s->indent ; j++)
118             qstring_append(s->str, "    ");
119     }
120 
121     to_json(obj, s->str, s->pretty, s->indent);
122     s->count++;
123 }
124 
125 static void to_json(const QObject *obj, QString *str, int pretty, int indent)
126 {
127     switch (qobject_type(obj)) {
128     case QTYPE_QINT: {
129         QInt *val = qobject_to_qint(obj);
130         char buffer[1024];
131 
132         snprintf(buffer, sizeof(buffer), "%" PRId64, qint_get_int(val));
133         qstring_append(str, buffer);
134         break;
135     }
136     case QTYPE_QSTRING: {
137         QString *val = qobject_to_qstring(obj);
138         const char *ptr;
139 
140         ptr = qstring_get_str(val);
141         qstring_append(str, "\"");
142         while (*ptr) {
143             if ((ptr[0] & 0xE0) == 0xE0 &&
144                 (ptr[1] & 0x80) && (ptr[2] & 0x80)) {
145                 uint16_t wchar;
146                 char escape[7];
147 
148                 wchar  = (ptr[0] & 0x0F) << 12;
149                 wchar |= (ptr[1] & 0x3F) << 6;
150                 wchar |= (ptr[2] & 0x3F);
151                 ptr += 2;
152 
153                 snprintf(escape, sizeof(escape), "\\u%04X", wchar);
154                 qstring_append(str, escape);
155             } else if ((ptr[0] & 0xE0) == 0xC0 && (ptr[1] & 0x80)) {
156                 uint16_t wchar;
157                 char escape[7];
158 
159                 wchar  = (ptr[0] & 0x1F) << 6;
160                 wchar |= (ptr[1] & 0x3F);
161                 ptr++;
162 
163                 snprintf(escape, sizeof(escape), "\\u%04X", wchar);
164                 qstring_append(str, escape);
165             } else switch (ptr[0]) {
166                 case '\"':
167                     qstring_append(str, "\\\"");
168                     break;
169                 case '\\':
170                     qstring_append(str, "\\\\");
171                     break;
172                 case '\b':
173                     qstring_append(str, "\\b");
174                     break;
175                 case '\f':
176                     qstring_append(str, "\\f");
177                     break;
178                 case '\n':
179                     qstring_append(str, "\\n");
180                     break;
181                 case '\r':
182                     qstring_append(str, "\\r");
183                     break;
184                 case '\t':
185                     qstring_append(str, "\\t");
186                     break;
187                 default: {
188                     if (ptr[0] <= 0x1F) {
189                         char escape[7];
190                         snprintf(escape, sizeof(escape), "\\u%04X", ptr[0]);
191                         qstring_append(str, escape);
192                     } else {
193                         char buf[2] = { ptr[0], 0 };
194                         qstring_append(str, buf);
195                     }
196                     break;
197                 }
198                 }
199             ptr++;
200         }
201         qstring_append(str, "\"");
202         break;
203     }
204     case QTYPE_QDICT: {
205         ToJsonIterState s;
206         QDict *val = qobject_to_qdict(obj);
207 
208         s.count = 0;
209         s.str = str;
210         s.indent = indent + 1;
211         s.pretty = pretty;
212         qstring_append(str, "{");
213         qdict_iter(val, to_json_dict_iter, &s);
214         if (pretty) {
215             int j;
216             qstring_append(str, "\n");
217             for (j = 0 ; j < indent ; j++)
218                 qstring_append(str, "    ");
219         }
220         qstring_append(str, "}");
221         break;
222     }
223     case QTYPE_QLIST: {
224         ToJsonIterState s;
225         QList *val = qobject_to_qlist(obj);
226 
227         s.count = 0;
228         s.str = str;
229         s.indent = indent + 1;
230         s.pretty = pretty;
231         qstring_append(str, "[");
232         qlist_iter(val, (void *)to_json_list_iter, &s);
233         if (pretty) {
234             int j;
235             qstring_append(str, "\n");
236             for (j = 0 ; j < indent ; j++)
237                 qstring_append(str, "    ");
238         }
239         qstring_append(str, "]");
240         break;
241     }
242     case QTYPE_QFLOAT: {
243         QFloat *val = qobject_to_qfloat(obj);
244         char buffer[1024];
245         int len;
246 
247         len = snprintf(buffer, sizeof(buffer), "%f", qfloat_get_double(val));
248         while (len > 0 && buffer[len - 1] == '0') {
249             len--;
250         }
251 
252         if (len && buffer[len - 1] == '.') {
253             buffer[len - 1] = 0;
254         } else {
255             buffer[len] = 0;
256         }
257 
258         qstring_append(str, buffer);
259         break;
260     }
261     case QTYPE_QBOOL: {
262         QBool *val = qobject_to_qbool(obj);
263 
264         if (qbool_get_int(val)) {
265             qstring_append(str, "true");
266         } else {
267             qstring_append(str, "false");
268         }
269         break;
270     }
271     case QTYPE_QERROR:
272         /* XXX: should QError be emitted? */
273     case QTYPE_NONE:
274         break;
275     }
276 }
277 
278 QString *qobject_to_json(const QObject *obj)
279 {
280     QString *str = qstring_new();
281 
282     to_json(obj, str, 0, 0);
283 
284     return str;
285 }
286 
287 QString *qobject_to_json_pretty(const QObject *obj)
288 {
289     QString *str = qstring_new();
290 
291     to_json(obj, str, 1, 0);
292 
293     return str;
294 }
295