1 files changed, 131 insertions, 0 deletions
diff --git a/QMP/qmp.py b/QMP/qmp.py
new file mode 100644
index 0000000..14ce8b0
--- /dev/null
+++ b/QMP/qmp.py
@@ -0,0 +1,131 @@
+# QEMU Monitor Protocol Python class
+# 
+# Copyright (C) 2009, 2010 Red Hat Inc.
+#
+# Authors:
+#  Luiz Capitulino <lcapitulino@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2.  See
+# the COPYING file in the top-level directory.
+
+import json
+import errno
+import socket
+
+class QMPError(Exception):
+    pass
+
+class QMPConnectError(QMPError):
+    pass
+
+class QMPCapabilitiesError(QMPError):
+    pass
+
+class QEMUMonitorProtocol:
+    def __init__(self, address):
+        """
+        Create a QEMUMonitorProtocol class.
+
+        @param address: QEMU address, can be either a unix socket path (string)
+                        or a tuple in the form ( address, port ) for a TCP
+                        connection
+        @note No connection is established, this is done by the connect() method
+        """
+        self.__events = []
+        self.__address = address
+        self.__sock = self.__get_sock()
+        self.__sockfile = self.__sock.makefile()
+
+    def __get_sock(self):
+        if isinstance(self.__address, tuple):
+            family = socket.AF_INET
+        else:
+            family = socket.AF_UNIX
+        return socket.socket(family, socket.SOCK_STREAM)
+
+    def __json_read(self):
+        while True:
+            data = self.__sockfile.readline()
+            if not data:
+                return
+            resp = json.loads(data)
+            if 'event' in resp:
+                self.__events.append(resp)
+                continue
+            return resp
+
+    error = socket.error
+
+    def connect(self):
+        """
+        Connect to the QMP Monitor and perform capabilities negotiation.
+
+        @return QMP greeting dict
+        @raise socket.error on socket connection errors
+        @raise QMPConnectError if the greeting is not received
+        @raise QMPCapabilitiesError if fails to negotiate capabilities
+        """
+        self.__sock.connect(self.__address)
+        greeting = self.__json_read()
+        if greeting is None or not greeting.has_key('QMP'):
+            raise QMPConnectError
+        # Greeting seems ok, negotiate capabilities
+        resp = self.cmd('qmp_capabilities')
+        if "return" in resp:
+            return greeting
+        raise QMPCapabilitiesError
+
+    def cmd_obj(self, qmp_cmd):
+        """
+        Send a QMP command to the QMP Monitor.
+
+        @param qmp_cmd: QMP command to be sent as a Python dict
+        @return QMP response as a Python dict or None if the connection has
+                been closed
+        """
+        try:
+            self.__sock.sendall(json.dumps(qmp_cmd))
+        except socket.error, err:
+            if err[0] == errno.EPIPE:
+                return
+            raise socket.error(err)
+        return self.__json_read()
+
+    def cmd(self, name, args=None, id=None):
+        """
+        Build a QMP command and send it to the QMP Monitor.
+
+        @param name: command name (string)
+        @param args: command arguments (dict)
+        @param id: command id (dict, list, string or int)
+        """
+        qmp_cmd = { 'execute': name }
+        if args:
+            qmp_cmd['arguments'] = args
+        if id:
+            qmp_cmd['id'] = id
+        return self.cmd_obj(qmp_cmd)
+
+    def get_events(self):
+        """
+        Get a list of available QMP events.
+        """
+        self.__sock.setblocking(0)
+        try:
+            self.__json_read()
+        except socket.error, err:
+            if err[0] == errno.EAGAIN:
+                # No data available
+                pass
+        self.__sock.setblocking(1)
+        return self.__events
+
+    def clear_events(self):
+        """
+        Clear current list of pending events.
+        """
+        self.__events = []
+
+    def close(self):
+        self.__sock.close()
+        self.__sockfile.close()