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 "qemu/osdep.h" |
15 | #include "qapi/error.h" |
16 | #include "qapi/qmp/json-parser.h" |
17 | #include "qapi/qmp/qjson.h" |
18 | #include "qapi/qmp/qbool.h" |
19 | #include "qapi/qmp/qdict.h" |
20 | #include "qapi/qmp/qlist.h" |
21 | #include "qapi/qmp/qnum.h" |
22 | #include "qapi/qmp/qstring.h" |
23 | #include "qemu/unicode.h" |
24 | |
25 | typedef struct JSONParsingState |
26 | { |
27 | JSONMessageParser parser; |
28 | QObject *result; |
29 | Error *err; |
30 | } JSONParsingState; |
31 | |
32 | static void consume_json(void *opaque, QObject *json, Error *err) |
33 | { |
34 | JSONParsingState *s = opaque; |
35 | |
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 | } |
49 | s->result = json; |
50 | s->err = err; |
51 | } |
52 | |
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) |
65 | { |
66 | JSONParsingState state = {}; |
67 | |
68 | json_message_parser_init(&state.parser, consume_json, &state, ap); |
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 | |
73 | if (!state.result && !state.err) { |
74 | error_setg(&state.err, "Expecting a JSON value" ); |
75 | } |
76 | |
77 | error_propagate(errp, state.err); |
78 | return state.result; |
79 | } |
80 | |
81 | QObject *qobject_from_json(const char *string, Error **errp) |
82 | { |
83 | return qobject_from_jsonv(string, NULL, errp); |
84 | } |
85 | |
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 | |
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, ...) |
111 | { |
112 | QObject *obj; |
113 | va_list ap; |
114 | |
115 | va_start(ap, string); |
116 | obj = qobject_from_vjsonf_nofail(string, ap); |
117 | va_end(ap); |
118 | |
119 | return obj; |
120 | } |
121 | |
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 | |
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 | { |
143 | QDict *qdict; |
144 | va_list ap; |
145 | |
146 | va_start(ap, string); |
147 | qdict = qdict_from_vjsonf_nofail(string, ap); |
148 | va_end(ap); |
149 | return qdict; |
150 | } |
151 | |
152 | typedef struct ToJsonIterState |
153 | { |
154 | int indent; |
155 | int pretty; |
156 | int count; |
157 | QString *str; |
158 | } ToJsonIterState; |
159 | |
160 | static void to_json(const QObject *obj, QString *str, int pretty, int indent); |
161 | |
162 | static void to_json_dict_iter(const char *key, QObject *obj, void *opaque) |
163 | { |
164 | ToJsonIterState *s = opaque; |
165 | QString *qkey; |
166 | int j; |
167 | |
168 | if (s->count) { |
169 | qstring_append(s->str, s->pretty ? "," : ", " ); |
170 | } |
171 | |
172 | if (s->pretty) { |
173 | qstring_append(s->str, "\n" ); |
174 | for (j = 0 ; j < s->indent ; j++) |
175 | qstring_append(s->str, " " ); |
176 | } |
177 | |
178 | qkey = qstring_from_str(key); |
179 | to_json(QOBJECT(qkey), s->str, s->pretty, s->indent); |
180 | qobject_unref(qkey); |
181 | |
182 | qstring_append(s->str, ": " ); |
183 | to_json(obj, s->str, s->pretty, s->indent); |
184 | s->count++; |
185 | } |
186 | |
187 | static void to_json_list_iter(QObject *obj, void *opaque) |
188 | { |
189 | ToJsonIterState *s = opaque; |
190 | int j; |
191 | |
192 | if (s->count) { |
193 | qstring_append(s->str, s->pretty ? "," : ", " ); |
194 | } |
195 | |
196 | if (s->pretty) { |
197 | qstring_append(s->str, "\n" ); |
198 | for (j = 0 ; j < s->indent ; j++) |
199 | qstring_append(s->str, " " ); |
200 | } |
201 | |
202 | to_json(obj, s->str, s->pretty, s->indent); |
203 | s->count++; |
204 | } |
205 | |
206 | static void to_json(const QObject *obj, QString *str, int pretty, int indent) |
207 | { |
208 | switch (qobject_type(obj)) { |
209 | case QTYPE_QNULL: |
210 | qstring_append(str, "null" ); |
211 | break; |
212 | case QTYPE_QNUM: { |
213 | QNum *val = qobject_to(QNum, obj); |
214 | char *buffer = qnum_to_string(val); |
215 | qstring_append(str, buffer); |
216 | g_free(buffer); |
217 | break; |
218 | } |
219 | case QTYPE_QSTRING: { |
220 | QString *val = qobject_to(QString, obj); |
221 | const char *ptr; |
222 | int cp; |
223 | char buf[16]; |
224 | char *end; |
225 | |
226 | ptr = qstring_get_str(val); |
227 | qstring_append(str, "\"" ); |
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 */ |
256 | } |
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; |
267 | } |
268 | qstring_append(str, buf); |
269 | } |
270 | }; |
271 | |
272 | qstring_append(str, "\"" ); |
273 | break; |
274 | } |
275 | case QTYPE_QDICT: { |
276 | ToJsonIterState s; |
277 | QDict *val = qobject_to(QDict, obj); |
278 | |
279 | s.count = 0; |
280 | s.str = str; |
281 | s.indent = indent + 1; |
282 | s.pretty = pretty; |
283 | qstring_append(str, "{" ); |
284 | qdict_iter(val, to_json_dict_iter, &s); |
285 | if (pretty) { |
286 | int j; |
287 | qstring_append(str, "\n" ); |
288 | for (j = 0 ; j < indent ; j++) |
289 | qstring_append(str, " " ); |
290 | } |
291 | qstring_append(str, "}" ); |
292 | break; |
293 | } |
294 | case QTYPE_QLIST: { |
295 | ToJsonIterState s; |
296 | QList *val = qobject_to(QList, obj); |
297 | |
298 | s.count = 0; |
299 | s.str = str; |
300 | s.indent = indent + 1; |
301 | s.pretty = pretty; |
302 | qstring_append(str, "[" ); |
303 | qlist_iter(val, (void *)to_json_list_iter, &s); |
304 | if (pretty) { |
305 | int j; |
306 | qstring_append(str, "\n" ); |
307 | for (j = 0 ; j < indent ; j++) |
308 | qstring_append(str, " " ); |
309 | } |
310 | qstring_append(str, "]" ); |
311 | break; |
312 | } |
313 | case QTYPE_QBOOL: { |
314 | QBool *val = qobject_to(QBool, obj); |
315 | |
316 | if (qbool_get_bool(val)) { |
317 | qstring_append(str, "true" ); |
318 | } else { |
319 | qstring_append(str, "false" ); |
320 | } |
321 | break; |
322 | } |
323 | default: |
324 | abort(); |
325 | } |
326 | } |
327 | |
328 | QString *qobject_to_json(const QObject *obj) |
329 | { |
330 | QString *str = qstring_new(); |
331 | |
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); |
342 | |
343 | return str; |
344 | } |
345 | |