2 * Copyright (C) 2014 - Jonathan Rajotte <jonathan.r.julien@gmail.com>
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
18 * Usage: extract_xml [-v|-e] xml_path xpath_expression
19 * Evaluate XPath expression and prints result node set.
20 * args[1] path to the xml file
21 * args[2] xpath expression to extract
22 * If -e look if node exist return "true" else nothing
23 * If -v is set the name of the node will appear with his value delimited by
26 * Command:extract_xml ../file.xml /test/node/text()
42 #include <libxml/tree.h>
43 #include <libxml/parser.h>
44 #include <libxml/xpath.h>
45 #include <libxml/xpathInternals.h>
47 #if defined(LIBXML_XPATH_ENABLED)
55 * nodes: the nodes set.
56 * output: the output file handle.
58 * Print the node content to the file
60 static int print_xpath_nodes(xmlDocPtr doc
, xmlNodeSetPtr nodes
, FILE *output
)
67 xmlChar
*node_child_value_string
= NULL
;
70 size
= (nodes
) ? nodes
->nodeNr
: 0;
72 for (i
= 0; i
< size
; ++i
) {
73 assert(nodes
->nodeTab
[i
]);
75 if (nodes
->nodeTab
[i
]->type
== XML_NAMESPACE_DECL
) {
76 fprintf(stderr
, "ERR:%s\n",
77 "This executable does not support xml namespacing\n");
80 } else if (nodes
->nodeTab
[i
]->type
== XML_ELEMENT_NODE
) {
81 cur
= nodes
->nodeTab
[i
];
83 if (xmlChildElementCount(cur
) == 0) {
84 if (xmlNodeIsText(cur
->children
)) {
85 node_child_value_string
= xmlNodeListGetString(doc
,
88 fprintf(output
, "true\n");
89 } else if (opt_verbose
) {
90 fprintf(output
, "%s;%s;\n", cur
->name
,
91 node_child_value_string
);
93 fprintf(output
, "%s\n",
94 node_child_value_string
);
96 xmlFree(node_child_value_string
);
98 /* We don't want to print non-final element */
100 fprintf(output
, "true\n");
102 fprintf(stderr
, "ERR:%s\n",
103 "Xpath expression return non-final xml element");
110 fprintf(output
, "true\n");
112 /* We don't want to print non-final element */
113 fprintf(stderr
, "ERR:%s\n",
114 "Xpath expression return non-final xml element");
121 cur
= nodes
->nodeTab
[i
];
123 fprintf(output
, "true\n");
124 } else if (opt_verbose
) {
125 fprintf(output
, "%s;%s;\n", cur
->parent
->name
, cur
->content
);
127 fprintf(output
, "%s\n", cur
->content
);
131 /* Command Success */
139 * Extract element corresponding to xpath
140 * xml_path The path to the xml file
141 * xpath: The xpath to evaluate.
143 * Evaluate an xpath expression onto an xml file.
144 * and print the result one by line.
146 * Returns 0 on success and a negative value otherwise.
148 static int extract_xpath(const char *xml_path
, const xmlChar
*xpath
)
150 xmlDocPtr doc
= NULL
;
151 xmlXPathContextPtr xpathCtx
= NULL
;
152 xmlXPathObjectPtr xpathObj
= NULL
;
157 /* Parse the xml file */
158 doc
= xmlParseFile(xml_path
);
160 fprintf(stderr
, "ERR parsing: xml file invalid \"%s\"\n", xml_path
);
164 /* Initialize a xpath context */
165 xpathCtx
= xmlXPathNewContext(doc
);
167 fprintf(stderr
, "ERR: XPath context invalid\n");
172 /* Evaluate xpath expression */
173 xpathObj
= xmlXPathEvalExpression(xpath
, xpathCtx
);
175 fprintf(stderr
, "ERR: invalid xpath expression \"%s\"\n", xpath
);
176 xmlXPathFreeContext(xpathCtx
);
182 if (print_xpath_nodes(doc
, xpathObj
->nodesetval
, stdout
)) {
183 xmlXPathFreeObject(xpathObj
);
184 xmlXPathFreeContext(xpathCtx
);
190 xmlXPathFreeObject(xpathObj
);
191 xmlXPathFreeContext(xpathCtx
);
197 int main(int argc
, char **argv
)
201 /* Parse command line and process file */
202 while ((opt
= getopt(argc
, argv
, "ve")) != -1) {
215 if (!(optind
+ 1 < argc
)) {
216 fprintf(stderr
, "ERR:%s\n", "Arguments missing");
222 xmlKeepBlanksDefault(0);
223 if (access(argv
[optind
], F_OK
)) {
224 fprintf(stderr
, "ERR:%s\n", "Xml path not valid");
227 /* Do the main job */
228 if (extract_xpath(argv
[optind
], (xmlChar
*)argv
[optind
+1])) {
232 /* Shutdown libxml */
241 fprintf(stderr
, "XPath support not compiled in\n");