qjson.c

   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 "json-lexer.h"
  15 #include "json-parser.h"
  16 #include "json-streamer.h"
  17 #include "qjson.h"
  18 #include "qint.h"
  19 #include "qlist.h"
  20 #include "qbool.h"
  21 #include "qfloat.h"
  22 #include "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 QObject *qobject_from_jsonf(const char *string, ...)
  57 {
  58     QObject *obj;
  59     va_list ap;
  60
  61     va_start(ap, string);
  62     obj = qobject_from_jsonv(string, &ap);
  63     va_end(ap);
  64
  65     return obj;
  66 }
  67
  68 typedef struct ToJsonIterState
  69 {
  70     int count;
  71     QString *str;
  72 } ToJsonIterState;
  73
  74 static void to_json(const QObject *obj, QString *str);
  75
  76 static void to_json_dict_iter(const char *key, QObject *obj, void *opaque)
  77 {
  78     ToJsonIterState *s = opaque;
  79     QString *qkey;
  80
  81     if (s->count) {
  82         qstring_append(s->str, ", ");
  83     }
  84
  85     qkey = qstring_from_str(key);
  86     to_json(QOBJECT(qkey), s->str);
  87     QDECREF(qkey);
  88
  89     qstring_append(s->str, ": ");
  90     to_json(obj, s->str);
  91     s->count++;
  92 }
  93
  94 static void to_json_list_iter(QObject *obj, void *opaque)
  95 {
  96     ToJsonIterState *s = opaque;
  97
  98     if (s->count) {
  99         qstring_append(s->str, ", ");
 100     }
 101
 102     to_json(obj, s->str);
 103     s->count++;
 104 }
 105
 106 static void to_json(const QObject *obj, QString *str)
 107 {
 108     switch (qobject_type(obj)) {
 109     case QTYPE_QINT: {
 110         QInt *val = qobject_to_qint(obj);
 111         char buffer[1024];
 112
 113         snprintf(buffer, sizeof(buffer), "%" PRId64, qint_get_int(val));
 114         qstring_append(str, buffer);
 115         break;
 116     }
 117     case QTYPE_QSTRING: {
 118         QString *val = qobject_to_qstring(obj);
 119         const char *ptr;
 120
 121         ptr = qstring_get_str(val);
 122         qstring_append(str, "\"");
 123         while (*ptr) {
 124             if ((ptr[0] & 0xE0) == 0xE0 &&
 125                 (ptr[1] & 0x80) && (ptr[2] & 0x80)) {
 126                 uint16_t wchar;
 127                 char escape[7];
 128
 129                 wchar  = (ptr[0] & 0x0F) << 12;
 130                 wchar |= (ptr[1] & 0x3F) << 6;
 131                 wchar |= (ptr[2] & 0x3F);
 132                 ptr += 2;
 133
 134                 snprintf(escape, sizeof(escape), "\\u%04X", wchar);
 135                 qstring_append(str, escape);
 136             } else if ((ptr[0] & 0xE0) == 0xC0 && (ptr[1] & 0x80)) {
 137                 uint16_t wchar;
 138                 char escape[7];
 139
 140                 wchar  = (ptr[0] & 0x1F) << 6;
 141                 wchar |= (ptr[1] & 0x3F);
 142                 ptr++;
 143
 144                 snprintf(escape, sizeof(escape), "\\u%04X", wchar);
 145                 qstring_append(str, escape);
 146             } else switch (ptr[0]) {
 147                 case '\"':
 148                     qstring_append(str, "\\\"");
 149                     break;
 150                 case '\\':
 151                     qstring_append(str, "\\\\");
 152                     break;
 153                 case '\b':
 154                     qstring_append(str, "\\b");
 155                     break;
 156                 case '\n':
 157                     qstring_append(str, "\\n");
 158                     break;
 159                 case '\r':
 160                     qstring_append(str, "\\r");
 161                     break;
 162                 case '\t':
 163                     qstring_append(str, "\\t");
 164                     break;
 165                 default: {
 166                     char buf[2] = { ptr[0], 0 };
 167                     qstring_append(str, buf);
 168                     break;
 169                 }
 170                 }
 171             ptr++;
 172         }
 173         qstring_append(str, "\"");
 174         break;
 175     }
 176     case QTYPE_QDICT: {
 177         ToJsonIterState s;
 178         QDict *val = qobject_to_qdict(obj);
 179
 180         s.count = 0;
 181         s.str = str;
 182         qstring_append(str, "{");
 183         qdict_iter(val, to_json_dict_iter, &s);
 184         qstring_append(str, "}");
 185         break;
 186     }
 187     case QTYPE_QLIST: {
 188         ToJsonIterState s;
 189         QList *val = qobject_to_qlist(obj);
 190
 191         s.count = 0;
 192         s.str = str;
 193         qstring_append(str, "[");
 194         qlist_iter(val, (void *)to_json_list_iter, &s);
 195         qstring_append(str, "]");
 196         break;
 197     }
 198     case QTYPE_QFLOAT: {
 199         QFloat *val = qobject_to_qfloat(obj);
 200         char buffer[1024];
 201         int len;
 202
 203         len = snprintf(buffer, sizeof(buffer), "%f", qfloat_get_double(val));
 204         while (len > 0 && buffer[len - 1] == '0') {
 205             len--;
 206         }
 207
 208         if (len && buffer[len - 1] == '.') {
 209             buffer[len - 1] = 0;
 210         } else {
 211             buffer[len] = 0;
 212         }
 213
 214         qstring_append(str, buffer);
 215         break;
 216     }
 217     case QTYPE_QBOOL: {
 218         QBool *val = qobject_to_qbool(obj);
 219
 220         if (qbool_get_int(val)) {
 221             qstring_append(str, "true");
 222         } else {
 223             qstring_append(str, "false");
 224         }
 225         break;
 226     }
 227     case QTYPE_QERROR:
 228         /* XXX: should QError be emitted? */
 229     case QTYPE_NONE:
 230         break;
 231     }
 232 }
 233
 234 QString *qobject_to_json(const QObject *obj)
 235 {
 236     QString *str = qstring_new();
 237
 238     to_json(obj, str);
 239
 240     return str;
 241 }