1<?xml version="1.0" encoding="UTF-8"?> 2<html> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> 5 <title>pattern: pattern expression handling</title> 6 <meta name="generator" content="Libxml2 devhelp stylesheet"/> 7 <link rel="start" href="index.html" title="libxml2 Reference Manual"/> 8 <link rel="up" href="general.html" title="API"/> 9 <link rel="stylesheet" href="style.css" type="text/css"/> 10 <link rel="chapter" href="general.html" title="API"/> 11 </head> 12 <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13 <table class="navigation" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2"> 14 <tr valign="middle"> 15 <td> 16 <a accesskey="p" href="libxml2-parserInternals.html"> 17 <img src="left.png" width="24" height="24" border="0" alt="Prev"/> 18 </a> 19 </td> 20 <td> 21 <a accesskey="u" href="general.html"> 22 <img src="up.png" width="24" height="24" border="0" alt="Up"/> 23 </a> 24 </td> 25 <td> 26 <a accesskey="h" href="index.html"> 27 <img src="home.png" width="24" height="24" border="0" alt="Home"/> 28 </a> 29 </td> 30 <td> 31 <a accesskey="n" href="libxml2-relaxng.html"> 32 <img src="right.png" width="24" height="24" border="0" alt="Next"/> 33 </a> 34 </td> 35 <th width="100%" align="center">libxml2 Reference Manual</th> 36 </tr> 37 </table> 38 <h2> 39 <span class="refentrytitle">pattern</span> 40 </h2> 41 <p>pattern - pattern expression handling</p> 42 <p>allows to compile and test pattern expressions for nodes either in a tree or based on a parser state. </p> 43 <p>Author(s): Daniel Veillard </p> 44 <div class="refsynopsisdiv"> 45 <h2>Synopsis</h2> 46 <pre class="synopsis">typedef <a href="libxml2-pattern.html#xmlStreamCtxt">xmlStreamCtxt</a> * <a href="#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a>; 47typedef enum <a href="#xmlPatternFlags">xmlPatternFlags</a>; 48typedef struct _xmlStreamCtxt <a href="#xmlStreamCtxt">xmlStreamCtxt</a>; 49typedef struct _xmlPattern <a href="#xmlPattern">xmlPattern</a>; 50typedef <a href="libxml2-pattern.html#xmlPattern">xmlPattern</a> * <a href="#xmlPatternPtr">xmlPatternPtr</a>; 51int <a href="#xmlPatternMinDepth">xmlPatternMinDepth</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 52<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> <a href="#xmlPatternGetStreamCtxt">xmlPatternGetStreamCtxt</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 53int <a href="#xmlPatternFromRoot">xmlPatternFromRoot</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 54void <a href="#xmlFreePatternList">xmlFreePatternList</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 55int <a href="#xmlPatternStreamable">xmlPatternStreamable</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 56int <a href="#xmlStreamPushAttr">xmlStreamPushAttr</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns); 57int <a href="#xmlPatternMatch">xmlPatternMatch</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp, <br/> <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node); 58int <a href="#xmlStreamWantsAnyNode">xmlStreamWantsAnyNode</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> streamCtxt); 59int <a href="#xmlStreamPop">xmlStreamPop</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream); 60void <a href="#xmlFreePattern">xmlFreePattern</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 61int <a href="#xmlStreamPush">xmlStreamPush</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns); 62int <a href="#xmlPatternMaxDepth">xmlPatternMaxDepth</a> (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp); 63<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> <a href="#xmlPatterncompile">xmlPatterncompile</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * pattern, <br/> <a href="libxml2-dict.html#xmlDict">xmlDict</a> * dict, <br/> int flags, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> ** namespaces); 64int <a href="#xmlStreamPushNode">xmlStreamPushNode</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns, <br/> int nodeType); 65void <a href="#xmlFreeStreamCtxt">xmlFreeStreamCtxt</a> (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream); 66</pre> 67 </div> 68 <div class="refsect1" lang="en"> 69 <h2>Description</h2> 70 </div> 71 <div class="refsect1" lang="en"> 72 <h2>Details</h2> 73 <div class="refsect2" lang="en"> 74 <div class="refsect2" lang="en"><h3><a name="xmlPattern">Structure </a>xmlPattern</h3><pre class="programlisting">struct _xmlPattern { 75The content of this structure is not made public by the API. 76} xmlPattern; 77</pre><p/> 78</div> 79 <hr/> 80 <div class="refsect2" lang="en"><h3><a name="xmlPatternFlags">Enum </a>xmlPatternFlags</h3><pre class="programlisting">enum <a href="#xmlPatternFlags">xmlPatternFlags</a> { 81 <a name="XML_PATTERN_DEFAULT">XML_PATTERN_DEFAULT</a> = 0 /* simple pattern match */ 82 <a name="XML_PATTERN_XPATH">XML_PATTERN_XPATH</a> = 1 /* standard XPath pattern */ 83 <a name="XML_PATTERN_XSSEL">XML_PATTERN_XSSEL</a> = 2 /* XPath subset for schema selector */ 84 <a name="XML_PATTERN_XSFIELD">XML_PATTERN_XSFIELD</a> = 4 /* XPath subset for schema field */ 85}; 86</pre><p/> 87</div> 88 <hr/> 89 <div class="refsect2" lang="en"><h3><a name="xmlPatternPtr">Typedef </a>xmlPatternPtr</h3><pre class="programlisting"><a href="libxml2-pattern.html#xmlPattern">xmlPattern</a> * xmlPatternPtr; 90</pre><p/> 91</div> 92 <hr/> 93 <div class="refsect2" lang="en"><h3><a name="xmlStreamCtxt">Structure </a>xmlStreamCtxt</h3><pre class="programlisting">struct _xmlStreamCtxt { 94The content of this structure is not made public by the API. 95} xmlStreamCtxt; 96</pre><p/> 97</div> 98 <hr/> 99 <div class="refsect2" lang="en"><h3><a name="xmlStreamCtxtPtr">Typedef </a>xmlStreamCtxtPtr</h3><pre class="programlisting"><a href="libxml2-pattern.html#xmlStreamCtxt">xmlStreamCtxt</a> * xmlStreamCtxtPtr; 100</pre><p/> 101</div> 102 <hr/> 103 <div class="refsect2" lang="en"><h3><a name="xmlFreePattern"/>xmlFreePattern ()</h3><pre class="programlisting">void xmlFreePattern (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 104</pre><p>Free up the memory allocated by @comp</p> 105<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>an XSLT comp</td></tr></tbody></table></div></div> 106 <hr/> 107 <div class="refsect2" lang="en"><h3><a name="xmlFreePatternList"/>xmlFreePatternList ()</h3><pre class="programlisting">void xmlFreePatternList (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 108</pre><p>Free up the memory allocated by all the elements of @comp</p> 109<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>an XSLT comp list</td></tr></tbody></table></div></div> 110 <hr/> 111 <div class="refsect2" lang="en"><h3><a name="xmlFreeStreamCtxt"/>xmlFreeStreamCtxt ()</h3><pre class="programlisting">void xmlFreeStreamCtxt (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream)<br/> 112</pre><p>Free the stream context</p> 113<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>stream</tt></i>:</span></td><td>the stream context</td></tr></tbody></table></div></div> 114 <hr/> 115 <div class="refsect2" lang="en"><h3><a name="xmlPatternFromRoot"/>xmlPatternFromRoot ()</h3><pre class="programlisting">int xmlPatternFromRoot (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 116</pre><p>Check if the pattern must be looked at from the root.</p> 117<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if true, 0 if false and -1 in case of error</td></tr></tbody></table></div></div> 118 <hr/> 119 <div class="refsect2" lang="en"><h3><a name="xmlPatternGetStreamCtxt"/>xmlPatternGetStreamCtxt ()</h3><pre class="programlisting"><a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> xmlPatternGetStreamCtxt (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 120</pre><p>Get a streaming context for that pattern Use <a href="libxml2-pattern.html#xmlFreeStreamCtxt">xmlFreeStreamCtxt</a> to free the context.</p> 121<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a pointer to the context or NULL in case of failure</td></tr></tbody></table></div></div> 122 <hr/> 123 <div class="refsect2" lang="en"><h3><a name="xmlPatternMatch"/>xmlPatternMatch ()</h3><pre class="programlisting">int xmlPatternMatch (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp, <br/> <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node)<br/> 124</pre><p>Test whether the node matches the pattern</p> 125<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>node</tt></i>:</span></td><td>a node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if it matches, 0 if it doesn't and -1 in case of failure</td></tr></tbody></table></div></div> 126 <hr/> 127 <div class="refsect2" lang="en"><h3><a name="xmlPatternMaxDepth"/>xmlPatternMaxDepth ()</h3><pre class="programlisting">int xmlPatternMaxDepth (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 128</pre><p>Check the maximum depth reachable by a pattern</p> 129<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-2 if no limit (using //), otherwise the depth, and -1 in case of error</td></tr></tbody></table></div></div> 130 <hr/> 131 <div class="refsect2" lang="en"><h3><a name="xmlPatternMinDepth"/>xmlPatternMinDepth ()</h3><pre class="programlisting">int xmlPatternMinDepth (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 132</pre><p>Check the minimum depth reachable by a pattern, 0 mean the / or . are part of the set.</p> 133<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error otherwise the depth,</td></tr></tbody></table></div></div> 134 <hr/> 135 <div class="refsect2" lang="en"><h3><a name="xmlPatternStreamable"/>xmlPatternStreamable ()</h3><pre class="programlisting">int xmlPatternStreamable (<a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> comp)<br/> 136</pre><p>Check if the pattern is streamable i.e. xmlPatternGetStreamCtxt() should work.</p> 137<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the precompiled pattern</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if streamable, 0 if not and -1 in case of error.</td></tr></tbody></table></div></div> 138 <hr/> 139 <div class="refsect2" lang="en"><h3><a name="xmlPatterncompile"/>xmlPatterncompile ()</h3><pre class="programlisting"><a href="libxml2-pattern.html#xmlPatternPtr">xmlPatternPtr</a> xmlPatterncompile (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * pattern, <br/> <a href="libxml2-dict.html#xmlDict">xmlDict</a> * dict, <br/> int flags, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> ** namespaces)<br/> 140</pre><p>Compile a pattern.</p> 141<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>pattern</tt></i>:</span></td><td>the pattern to compile</td></tr><tr><td><span class="term"><i><tt>dict</tt></i>:</span></td><td>an optional dictionary for interned strings</td></tr><tr><td><span class="term"><i><tt>flags</tt></i>:</span></td><td>compilation flags, see <a href="libxml2-pattern.html#xmlPatternFlags">xmlPatternFlags</a></td></tr><tr><td><span class="term"><i><tt>namespaces</tt></i>:</span></td><td>the prefix definitions, array of [URI, prefix] or NULL</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the compiled form of the pattern or NULL in case of error</td></tr></tbody></table></div></div> 142 <hr/> 143 <div class="refsect2" lang="en"><h3><a name="xmlStreamPop"/>xmlStreamPop ()</h3><pre class="programlisting">int xmlStreamPop (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream)<br/> 144</pre><p>push one level from the stream.</p> 145<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>stream</tt></i>:</span></td><td>the stream context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error, 0 otherwise.</td></tr></tbody></table></div></div> 146 <hr/> 147 <div class="refsect2" lang="en"><h3><a name="xmlStreamPush"/>xmlStreamPush ()</h3><pre class="programlisting">int xmlStreamPush (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns)<br/> 148</pre><p>Push new data onto the stream. NOTE: if the call xmlPatterncompile() indicated a dictionary, then strings for name and ns will be expected to come from the dictionary. Both @name and @ns being NULL means the / i.e. the root of the document. This can also act as a reset. Otherwise the function will act as if it has been given an element-node.</p> 149<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>stream</tt></i>:</span></td><td>the stream context</td></tr><tr><td><span class="term"><i><tt>name</tt></i>:</span></td><td>the current name</td></tr><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>the namespace name</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.</td></tr></tbody></table></div></div> 150 <hr/> 151 <div class="refsect2" lang="en"><h3><a name="xmlStreamPushAttr"/>xmlStreamPushAttr ()</h3><pre class="programlisting">int xmlStreamPushAttr (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns)<br/> 152</pre><p>Push new <a href="libxml2-SAX.html#attribute">attribute</a> data onto the stream. NOTE: if the call xmlPatterncompile() indicated a dictionary, then strings for name and ns will be expected to come from the dictionary. Both @name and @ns being NULL means the / i.e. the root of the document. This can also act as a reset. Otherwise the function will act as if it has been given an attribute-node.</p> 153<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>stream</tt></i>:</span></td><td>the stream context</td></tr><tr><td><span class="term"><i><tt>name</tt></i>:</span></td><td>the current name</td></tr><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>the namespace name</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.</td></tr></tbody></table></div></div> 154 <hr/> 155 <div class="refsect2" lang="en"><h3><a name="xmlStreamPushNode"/>xmlStreamPushNode ()</h3><pre class="programlisting">int xmlStreamPushNode (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> stream, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns, <br/> int nodeType)<br/> 156</pre><p>Push new data onto the stream. NOTE: if the call xmlPatterncompile() indicated a dictionary, then strings for name and ns will be expected to come from the dictionary. Both @name and @ns being NULL means the / i.e. the root of the document. This can also act as a reset. Different from xmlStreamPush() this function can be fed with nodes of type: element-, attribute-, text-, cdata-section-, comment- and processing-instruction-node.</p> 157<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>stream</tt></i>:</span></td><td>the stream context</td></tr><tr><td><span class="term"><i><tt>name</tt></i>:</span></td><td>the current name</td></tr><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>the namespace name</td></tr><tr><td><span class="term"><i><tt>nodeType</tt></i>:</span></td><td>the type of the node being pushed</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.</td></tr></tbody></table></div></div> 158 <hr/> 159 <div class="refsect2" lang="en"><h3><a name="xmlStreamWantsAnyNode"/>xmlStreamWantsAnyNode ()</h3><pre class="programlisting">int xmlStreamWantsAnyNode (<a href="libxml2-pattern.html#xmlStreamCtxtPtr">xmlStreamCtxtPtr</a> streamCtxt)<br/> 160</pre><p>Query if the streaming pattern additionally needs to be fed with text-, cdata-section-, comment- and processing-instruction-nodes. If the result is 0 then only element-nodes and attribute-nodes need to be pushed.</p> 161<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>streamCtxt</tt></i>:</span></td><td>the stream context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 in case of need of nodes of the above described types, 0 otherwise. -1 on API errors.</td></tr></tbody></table></div></div> 162 <hr/> 163 </div> 164 </div> 165 </body> 166</html> 167