1 files changed, 103 insertions, 1 deletions

diff --git a/trace-xml.c b/trace-xml.c
index 0bc130c..47cb3c9 100644
--- a/trace-xml.c
+++ b/trace-xml.c
@@ -25,13 +25,20 @@
 
 #include <libxml/xmlwriter.h>
 #include <libxml/parser.h>
-#include <libxml/encoding.h>
+#include <libxml/xpath.h>
 
 #include "trace-cmd.h"
 #include "trace-xml.h"
 
 struct tracecmd_xml_handle {
         xmlTextWriterPtr        writer;
+        xmlDocPtr               doc;
+};
+
+struct tracecmd_xml_system {
+        struct tracecmd_xml_handle *handle;
+        xmlXPathObjectPtr       result;
+        xmlNodePtr              cur;
 };
 
 #define TRACE_ENCODING "UTF-8"
@@ -122,6 +129,101 @@ void tracecmd_xml_close(struct tracecmd_xml_handle *handle)
                 xmlTextWriterEndDocument(handle->writer);
                 xmlFreeTextWriter(handle->writer);
         }
+        if (handle->doc) {
+                xmlFreeDoc(handle->doc);
+        }
+        free(handle);
+}
+
+/***********************************************************/
+/***  Reading XML files                                  ***/
+/***********************************************************/
+
+
+struct tracecmd_xml_handle *tracecmd_xml_open(const char *file)
+{
+        struct tracecmd_xml_handle *handle;
 
+        handle = malloc_or_die(sizeof(*handle));
+        memset(handle, 0, sizeof(*handle));
+
+        handle->doc = xmlParseFile(file);
+        if (!handle->doc)
+                goto fail_free;
+
+        return handle;
+
+ fail_free:
         free(handle);
+        return NULL;
+}
+
+struct tracecmd_xml_system *
+tracecmd_xml_find_system(struct tracecmd_xml_handle *handle,
+                         const char *system)
+{
+        struct tracecmd_xml_system *sys;
+        xmlXPathContextPtr context;
+        xmlXPathObjectPtr result;
+        xmlChar *xpath;
+        char *path;
+
+        path = malloc_or_die(strlen(system) + 3);
+        sprintf(path, "//%s", system);
+        xpath = BAD_CAST path;
+
+        context = xmlXPathNewContext(handle->doc);
+        result = xmlXPathEvalExpression(xpath, context);
+        free(path);
+
+        if (xmlXPathNodeSetIsEmpty(result->nodesetval)) {
+                xmlXPathFreeObject(result);
+                return NULL;
+        }
+
+        sys = malloc_or_die(sizeof(*sys));
+        sys->handle = handle;
+        sys->result = result;
+        sys->cur = result->nodesetval->nodeTab[0]->xmlChildrenNode;
+
+        return sys;
+}
+
+struct tracecmd_xml_system_node *
+tracecmd_xml_system_node(struct tracecmd_xml_system *system)
+{
+        return (struct tracecmd_xml_system_node *)system->cur;
+}
+
+const char *tracecmd_xml_node_type(struct tracecmd_xml_system_node *tnode)
+{
+        xmlNodePtr node = (xmlNodePtr)tnode;
+        return (const char *)node->name;
+}
+
+struct tracecmd_xml_system_node *
+tracecmd_xml_node_child(struct tracecmd_xml_system_node *tnode)
+{
+        xmlNodePtr node = (xmlNodePtr)tnode;
+        return (struct tracecmd_xml_system_node *)node->xmlChildrenNode;
+}
+
+struct tracecmd_xml_system_node *
+tracecmd_xml_node_next(struct tracecmd_xml_system_node *tnode)
+{
+        xmlNodePtr node = (xmlNodePtr)tnode;
+        return (struct tracecmd_xml_system_node *)node->next;
+}
+
+const char *tracecmd_xml_node_value(struct tracecmd_xml_handle *handle,
+                                    struct tracecmd_xml_system_node *tnode)
+{
+        xmlNodePtr node = (xmlNodePtr)tnode;
+        return (const char *)xmlNodeListGetString(handle->doc, node->xmlChildrenNode, 1);
+}
+
+void tracecmd_xml_free_system(struct tracecmd_xml_system *system)
+{
+        xmlXPathFreeObject(system->result);
+        free(system);
 }