Merge from bittboy/buildroot@db180c0

support/testing/tests/download/gitremote.py

@@ -0,0 +1,46 @@
+# subprocess does not kill the child daemon when a test case fails by raising
+# an exception. So use pexpect instead.
+import infra
+
+import pexpect
+
+
+GIT_REMOTE_PORT_INITIAL = 9418
+GIT_REMOTE_PORT_LAST = GIT_REMOTE_PORT_INITIAL + 99
+
+
+class GitRemote(object):
+    def __init__(self, builddir, serveddir, logtofile):
+        """
+        Start a local git server.
+
+        In order to support test cases in parallel, select the port the
+        server will listen to in runtime. Since there is no reliable way
+        to allocate the port prior to starting the server (another
+        process in the host machine can use the port between it is
+        selected from a list and it is really allocated to the server)
+        try to start the server in a port and in the case it is already
+        in use, try the next one in the allowed range.
+        """
+        self.daemon = None
+        self.port = None
+        self.logfile = infra.open_log_file(builddir, "gitremote", logtofile)
+
+        daemon_cmd = ["git", "daemon", "--reuseaddr", "--verbose",
+                      "--listen=localhost", "--export-all",
+                      "--base-path={}".format(serveddir)]
+        for port in range(GIT_REMOTE_PORT_INITIAL, GIT_REMOTE_PORT_LAST + 1):
+            cmd = daemon_cmd + ["--port={port}".format(port=port)]
+            self.logfile.write("> starting git remote with '{}'\n".format(" ".join(cmd)))
+            self.daemon = pexpect.spawn(cmd[0], cmd[1:], logfile=self.logfile)
+            ret = self.daemon.expect(["Ready to rumble",
+                                      "Address already in use"])
+            if ret == 0:
+                self.port = port
+                return
+        raise SystemError("Could not find a free port to run git remote")
+
+    def stop(self):
+        if self.daemon is None:
+            return
+        self.daemon.terminate(force=True)