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  24 <a href="#json-glib-JSON-GVariant-Integration.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#json-glib-JSON-GVariant-Integration.description" class="shortcut">Description</a>
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  29 <div class="refentry">
  30 <a name="json-glib-JSON-GVariant-Integration"></a><div class="titlepage"></div>
  31 <div class="refnamediv"><table width="100%"><tr>
  32 <td valign="top">
  33 <h2><span class="refentrytitle"><a name="json-glib-JSON-GVariant-Integration.top_of_page"></a>JSON GVariant Integration</span></h2>
  34 <p>JSON GVariant Integration — Serialize and deserialize GVariant types</p>
  35 </td>
  36 <td valign="top" align="right"></td>
  37 </tr></table></div>
  38 <div class="refsynopsisdiv">
  39 <a name="json-glib-JSON-GVariant-Integration.synopsis"></a><h2>Synopsis</h2>
  40 <pre class="synopsis"><a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="returnvalue">JsonNode</span></a> *          <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-serialize" title="json_gvariant_serialize ()">json_gvariant_serialize</a>             (<em class="parameter"><code><span class="type">GVariant</span> *variant</code></em>);
  41 <span class="returnvalue">gchar</span> *             <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-serialize-data" title="json_gvariant_serialize_data ()">json_gvariant_serialize_data</a>        (<em class="parameter"><code><span class="type">GVariant</span> *variant</code></em>,
  42                                                          <em class="parameter"><code><span class="type">gsize</span> *length</code></em>);
  43 <span class="returnvalue">GVariant</span> *          <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize" title="json_gvariant_deserialize ()">json_gvariant_deserialize</a>           (<em class="parameter"><code><a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> *json_node</code></em>,
  44                                                          <em class="parameter"><code>const <span class="type">gchar</span> *signature</code></em>,
  45                                                          <em class="parameter"><code><span class="type">GError</span> **error</code></em>);
  46 <span class="returnvalue">GVariant</span> *          <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize-data" title="json_gvariant_deserialize_data ()">json_gvariant_deserialize_data</a>      (<em class="parameter"><code>const <span class="type">gchar</span> *json</code></em>,
  47                                                          <em class="parameter"><code><span class="type">gssize</span> length</code></em>,
  48                                                          <em class="parameter"><code>const <span class="type">gchar</span> *signature</code></em>,
  49                                                          <em class="parameter"><code><span class="type">GError</span> **error</code></em>);
  50 </pre>
  51 </div>
  52 <div class="refsect1">
  53 <a name="json-glib-JSON-GVariant-Integration.description"></a><h2>Description</h2>
  54 <p>
  55 Use <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-serialize" title="json_gvariant_serialize ()"><code class="function">json_gvariant_serialize()</code></a> and <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-serialize-data" title="json_gvariant_serialize_data ()"><code class="function">json_gvariant_serialize_data()</code></a> to
  56 convert from any <span class="type">GVariant</span> value to a <a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> tree or its string
  57 representation.
  58 </p>
  59 <p>
  60 Use <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize" title="json_gvariant_deserialize ()"><code class="function">json_gvariant_deserialize()</code></a> and <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize-data" title="json_gvariant_deserialize_data ()"><code class="function">json_gvariant_deserialize_data()</code></a> to
  61 obtain the <span class="type">GVariant</span> value from a <a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> tree or directly from a JSON
  62 string.
  63 Since many <span class="type">GVariant</span> data types cannot be directly represented as
  64 JSON, a <span class="type">GVariant</span> type string (signature) should be provided to these
  65 methods in order to obtain a correct, type-contrained result.
  66 If no signature is provided, conversion can still be done, but the
  67 resulting <span class="type">GVariant</span> value will be "guessed" from the JSON data types,
  68 according to the following table:
  69 </p>
  70 <p>
  71 </p>
  72 <div class="table">
  73 <a name="id2971653"></a><p class="title"><b>Table 2. Default JSON to GVariant conversion (without signature constrains)</b></p>
  74 <div class="table-contents"><table summary="Default JSON to GVariant conversion (without signature constrains)" border="1">
  75 <colgroup>
  76 <col>
  77 <col>
  78 </colgroup>
  79 <thead><tr>
  80 <th align="left">JSON</th>
  81 <th align="left">GVariant</th>
  82 </tr></thead>
  83 <tfoot>
  84 <tr>
  85 <th align="left">string</th>
  86 <th align="left">string (s)</th>
  87 </tr>
  88 <tr>
  89 <th align="left">int64</th>
  90 <th align="left">int64 (x)</th>
  91 </tr>
  92 <tr>
  93 <th align="left">boolean</th>
  94 <th align="left">boolean (b)</th>
  95 </tr>
  96 <tr>
  97 <th align="left">double</th>
  98 <th align="left">double (d)</th>
  99 </tr>
 100 <tr>
 101 <th align="left">array</th>
 102 <th align="left">array of variants (av)</th>
 103 </tr>
 104 <tr>
 105 <th align="left">object</th>
 106 <th align="left">dictionary of string-variant (a{sv})</th>
 107 </tr>
 108 <tr>
 109 <th align="left">null</th>
 110 <th align="left">maybe variant (mv)</th>
 111 </tr>
 112 </tfoot>
 113 </table></div>
 114 </div>
 115 <p><br class="table-break">
 116 </p>
 117 </div>
 118 <div class="refsect1">
 119 <a name="json-glib-JSON-GVariant-Integration.details"></a><h2>Details</h2>
 120 <div class="refsect2">
 121 <a name="json-gvariant-serialize"></a><h3>json_gvariant_serialize ()</h3>
 122 <pre class="programlisting"><a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="returnvalue">JsonNode</span></a> *          json_gvariant_serialize             (<em class="parameter"><code><span class="type">GVariant</span> *variant</code></em>);</pre>
 123 <p>
 124 Converts <em class="parameter"><code>variant</code></em> to a JSON tree.
 125 </p>
 126 <div class="variablelist"><table border="0">
 127 <col align="left" valign="top">
 128 <tbody>
 129 <tr>
 130 <td><p><span class="term"><em class="parameter"><code>variant</code></em> :</span></p></td>
 131 <td>A <span class="type">GVariant</span> to convert</td>
 132 </tr>
 133 <tr>
 134 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 135 <td>A <a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> representing the root of the
 136 JSON data structure obtained from <em class="parameter"><code>variant</code></em>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
 137 </td>
 138 </tr>
 139 </tbody>
 140 </table></div>
 141 <p class="since">Since 0.14</p>
 142 </div>
 143 <hr>
 144 <div class="refsect2">
 145 <a name="json-gvariant-serialize-data"></a><h3>json_gvariant_serialize_data ()</h3>
 146 <pre class="programlisting"><span class="returnvalue">gchar</span> *             json_gvariant_serialize_data        (<em class="parameter"><code><span class="type">GVariant</span> *variant</code></em>,
 147                                                          <em class="parameter"><code><span class="type">gsize</span> *length</code></em>);</pre>
 148 <p>
 149 Converts <em class="parameter"><code>variant</code></em> to its JSON encoded string representation. This method
 150 is actually a helper function. It uses <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-serialize" title="json_gvariant_serialize ()"><code class="function">json_gvariant_serialize()</code></a> to obtain the
 151 JSON tree, and then <a class="link" href="JsonGenerator.html" title="JsonGenerator"><span class="type">JsonGenerator</span></a> to stringify it.
 152 </p>
 153 <div class="variablelist"><table border="0">
 154 <col align="left" valign="top">
 155 <tbody>
 156 <tr>
 157 <td><p><span class="term"><em class="parameter"><code>variant</code></em> :</span></p></td>
 158 <td>A <span class="type">GVariant</span> to convert</td>
 159 </tr>
 160 <tr>
 161 <td><p><span class="term"><em class="parameter"><code>length</code></em> :</span></p></td>
 162 <td>Return location for the length of the returned
 163 string, or <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a>. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>][<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span>
 164 </td>
 165 </tr>
 166 <tr>
 167 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 168 <td>The JSON encoded string corresponding to
 169 <em class="parameter"><code>variant</code></em>. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
 170 </td>
 171 </tr>
 172 </tbody>
 173 </table></div>
 174 <p class="since">Since 0.14</p>
 175 </div>
 176 <hr>
 177 <div class="refsect2">
 178 <a name="json-gvariant-deserialize"></a><h3>json_gvariant_deserialize ()</h3>
 179 <pre class="programlisting"><span class="returnvalue">GVariant</span> *          json_gvariant_deserialize           (<em class="parameter"><code><a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> *json_node</code></em>,
 180                                                          <em class="parameter"><code>const <span class="type">gchar</span> *signature</code></em>,
 181                                                          <em class="parameter"><code><span class="type">GError</span> **error</code></em>);</pre>
 182 <p>
 183 Converts a JSON data structure to a GVariant value using <em class="parameter"><code>signature</code></em> to
 184 resolve ambiguous data types. If no error occurs, the resulting <span class="type">GVariant</span>
 185 is guaranteed to conform to <em class="parameter"><code>signature</code></em>.
 186 </p>
 187 <p>
 188 If <em class="parameter"><code>signature</code></em> is not <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a> but does not represent a valid GVariant type
 189 string, <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a> is returned and error is set to <code class="literal">G_IO_ERROR_INVALID_ARGUMENT</code>.
 190 If a <em class="parameter"><code>signature</code></em> is provided but the JSON structure cannot be mapped to it,
 191 <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a> is returned and error is set to <code class="literal">G_IO_ERROR_INVALID_DATA</code>.
 192 If <em class="parameter"><code>signature</code></em> is <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a>, the conversion is done based strictly on the types
 193 in the JSON nodes.
 194 </p>
 195 <div class="variablelist"><table border="0">
 196 <col align="left" valign="top">
 197 <tbody>
 198 <tr>
 199 <td><p><span class="term"><em class="parameter"><code>json_node</code></em> :</span></p></td>
 200 <td>A <a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> to convert</td>
 201 </tr>
 202 <tr>
 203 <td><p><span class="term"><em class="parameter"><code>signature</code></em> :</span></p></td>
 204 <td>A valid <span class="type">GVariant</span> type string, or <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a>. <span class="annotation">[<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span>
 205 </td>
 206 </tr>
 207 <tr>
 208 <td><p><span class="term"><em class="parameter"><code>error</code></em> :</span></p></td>
 209 <td>A pointer to a <span class="type">GError</span>
 210 </td>
 211 </tr>
 212 <tr>
 213 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 214 <td>A newly created <span class="type">GVariant</span> compliant with
 215 <em class="parameter"><code>signature</code></em>, or <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a> on error. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
 216 </td>
 217 </tr>
 218 </tbody>
 219 </table></div>
 220 <p class="since">Since 0.14</p>
 221 </div>
 222 <hr>
 223 <div class="refsect2">
 224 <a name="json-gvariant-deserialize-data"></a><h3>json_gvariant_deserialize_data ()</h3>
 225 <pre class="programlisting"><span class="returnvalue">GVariant</span> *          json_gvariant_deserialize_data      (<em class="parameter"><code>const <span class="type">gchar</span> *json</code></em>,
 226                                                          <em class="parameter"><code><span class="type">gssize</span> length</code></em>,
 227                                                          <em class="parameter"><code>const <span class="type">gchar</span> *signature</code></em>,
 228                                                          <em class="parameter"><code><span class="type">GError</span> **error</code></em>);</pre>
 229 <p>
 230 Converts a JSON string to a <span class="type">GVariant</span> value. This method works exactly
 231 like <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize" title="json_gvariant_deserialize ()"><code class="function">json_gvariant_deserialize()</code></a>, but takes a JSON encoded string instead.
 232 The string is first converted to a <a class="link" href="json-glib-JSON-Node.html#JsonNode" title="JsonNode"><span class="type">JsonNode</span></a> using <a class="link" href="JsonParser.html" title="JsonParser"><span class="type">JsonParser</span></a>, and then
 233 <a class="link" href="json-glib-JSON-GVariant-Integration.html#json-gvariant-deserialize" title="json_gvariant_deserialize ()"><code class="function">json_gvariant_deserialize()</code></a> is called.
 234 </p>
 235 <div class="variablelist"><table border="0">
 236 <col align="left" valign="top">
 237 <tbody>
 238 <tr>
 239 <td><p><span class="term"><em class="parameter"><code>json</code></em> :</span></p></td>
 240 <td>A JSON data string</td>
 241 </tr>
 242 <tr>
 243 <td><p><span class="term"><em class="parameter"><code>length</code></em> :</span></p></td>
 244 <td>The length of <em class="parameter"><code>json</code></em>, or -1 if <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a>-terminated</td>
 245 </tr>
 246 <tr>
 247 <td><p><span class="term"><em class="parameter"><code>signature</code></em> :</span></p></td>
 248 <td>A valid <span class="type">GVariant</span> type string, or <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a>. <span class="annotation">[<acronym title="NULL is ok, both for passing and for returning."><span class="acronym">allow-none</span></acronym>]</span>
 249 </td>
 250 </tr>
 251 <tr>
 252 <td><p><span class="term"><em class="parameter"><code>error</code></em> :</span></p></td>
 253 <td>A pointer to a <span class="type">GError</span>
 254 </td>
 255 </tr>
 256 <tr>
 257 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 258 <td>A newly created <span class="type">GVariant</span> compliant with
 259 <em class="parameter"><code>signature</code></em>, or <a href="/home/ebassi/gnome3/install/share/gtk-doc/html/liboil/liboil-liboiljunk.html#NULL--CAPS"><code class="literal">NULL</code></a> on error. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span>
 260 </td>
 261 </tr>
 262 </tbody>
 263 </table></div>
 264 <p class="since">Since 0.14</p>
 265 </div>
 266 </div>
 267 </div>
 268 <div class="footer">
 269 <hr>
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