Initial commit

vrtManager/util.py

@@ -0,0 +1,129 @@
+#
+# Copyright (C) 2013 Webvirtmgr.
+#
+import re
+import random
+import libxml2
+import libvirt
+
+
+def is_kvm_available(xml):
+    capabilites = re.search('kvm', xml)
+    if capabilites:
+        return True
+    else:
+        return False
+
+
+def randomMAC():
+    """Generate a random MAC address."""
+    # qemu MAC
+    oui = [0x52, 0x54, 0x00]
+
+    mac = oui + [random.randint(0x00, 0xff),
+                 random.randint(0x00, 0xff),
+                 random.randint(0x00, 0xff)]
+    return ':'.join(map(lambda x: "%02x" % x, mac))
+
+
+def randomUUID():
+    """Generate a random UUID."""
+
+    u = [random.randint(0, 255) for dummy in range(0, 16)]
+    return "-".join(["%02x" * 4, "%02x" * 2, "%02x" * 2, "%02x" * 2, "%02x" * 6]) % tuple(u)
+
+
+def get_max_vcpus(conn, type=None):
+    """@param conn: libvirt connection to poll for max possible vcpus
+       @type type: optional guest type (kvm, etc.)"""
+    if type is None:
+        type = conn.getType()
+    try:
+        m = conn.getMaxVcpus(type.lower())
+    except libvirt.libvirtError:
+        m = 32
+    return m
+
+
+def xml_escape(str):
+    """Replaces chars ' " < > & with xml safe counterparts"""
+    if str is None:
+        return None
+
+    str = str.replace("&", "&amp;")
+    str = str.replace("'", "&apos;")
+    str = str.replace("\"", "&quot;")
+    str = str.replace("<", "&lt;")
+    str = str.replace(">", "&gt;")
+    return str
+
+
+def compareMAC(p, q):
+    """Compare two MAC addresses"""
+    pa = p.split(":")
+    qa = q.split(":")
+
+    if len(pa) != len(qa):
+        if p > q:
+            return 1
+        else:
+            return -1
+
+    for i in xrange(len(pa)):
+        n = int(pa[i], 0x10) - int(qa[i], 0x10)
+        if n > 0:
+            return 1
+        elif n < 0:
+            return -1
+    return 0
+
+
+def get_xml_path(xml, path=None, func=None):
+    """
+    Return the content from the passed xml xpath, or return the result
+    of a passed function (receives xpathContext as its only arg)
+    """
+    doc = None
+    ctx = None
+    result = None
+
+    try:
+        doc = libxml2.parseDoc(xml)
+        ctx = doc.xpathNewContext()
+
+        if path:
+            ret = ctx.xpathEval(path)
+            if ret is not None:
+                if type(ret) == list:
+                    if len(ret) >= 1:
+                        result = ret[0].content
+                else:
+                    result = ret
+
+        elif func:
+            result = func(ctx)
+
+        else:
+            raise ValueError("'path' or 'func' is required.")
+    finally:
+        if doc:
+            doc.freeDoc()
+        if ctx:
+            ctx.xpathFreeContext()
+    return result
+
+
+def pretty_mem(val):
+    val = int(val)
+    if val > (10 * 1024 * 1024):
+        return "%2.2f GB" % (val / (1024.0 * 1024.0))
+    else:
+        return "%2.0f MB" % (val / 1024.0)
+
+
+def pretty_bytes(val):
+    val = int(val)
+    if val > (1024 * 1024 * 1024):
+        return "%2.2f GB" % (val / (1024.0 * 1024.0 * 1024.0))
+    else:
+        return "%2.2f MB" % (val / (1024.0 * 1024.0))