[libvirt] [PATCH 1/2] virsh.c: new xPathULong() to parse XML returning ulong value of selected node.

[Michal Privoznik]

Parse XML from given buffer, select appropiate XPath node and return its
value as unsigned long.
---
 tools/virsh.c |   49 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 49 insertions(+), 0 deletions(-)

diff --git a/tools/virsh.c b/tools/virsh.c
index 50d5e33..8804fc3 100644
--- a/tools/virsh.c
+++ b/tools/virsh.c
@@ -2270,6 +2270,55 @@ static const vshCmdInfo info_freecell[] = {
     {NULL, NULL}
 };
 
+static int
+xPathULong(char *xml, char *xpath, unsigned long *value) {
+
+    xmlDocPtr doc = NULL;
+    xmlXPathContextPtr ctxt = NULL;
+    xmlXPathObjectPtr obj = NULL;
+    int ret = -1;
+
+    doc = xmlReadDoc((const xmlChar *) xml, "domain.xml", NULL,
+                     XML_PARSE_NOENT | XML_PARSE_NONET | XML_PARSE_NOWARNING);
+    if (!doc)
+        goto cleanup;
+
+    ctxt = xmlXPathNewContext(doc);
+    if (!ctxt)
+        goto cleanup;
+
+    obj = xmlXPathEval(BAD_CAST xpath, ctxt);
+    if (!obj)
+        goto cleanup;
+
+    if (!value)
+        goto cleanup;
+
+    *value = 0;
+    if ((obj->type == XPATH_STRING) &&
+        (obj->stringval != NULL) && (obj->stringval[0] != 0)) {
+            char *conv = NULL;
+            unsigned long val;
+
+            val = strtoul((const char *) obj->stringval, &conv, 10);
+            if (*conv =='\0') {
+                *value = val;
+                ret = 0;
+            }
+    } else if ((obj != NULL) && (obj->type == XPATH_NUMBER)) {
+        *value = (unsigned long) obj->floatval;
+        if (*value == obj->floatval) {
+            ret = 0;
+        }
+    }
+
+cleanup:
+    xmlXPathFreeObject(obj);
+    xmlXPathFreeContext(ctxt);
+    xmlFreeDoc(doc);
+    return ret;
+}
+
 static const vshCmdOptDef opts_freecell[] = {
     {"cellno", VSH_OT_INT, 0, N_("NUMA cell number")},
     {"all", VSH_OT_BOOL, 0, N_("show free memory for all NUMA cells")},
-- 
1.7.3.5