CHOP-661: add and use code to listen on next available server port.

In indra/llmessage/tests/testrunner.py, introduce new freeport() function to
try a caller-specified expression (such as instantiating an object that will
listen on a server port) with a range of candidate port numbers until the
expression produces a value instead of EADDRINUSE exception.
Change test_llsdmessage_peer.py and test_llxmlrpc_peer.py to use freeport() to
construct their server class inline BEFORE launching the thread that will run
it, then pass that server's serve_forever method to daemon thread. Also set
os.environ["PORT"] to selected environment variable before running subject
test program.
In indra/llmessage/tests/commtest.h, introduce commtest_data::getport() to
read port number from specified environment variable, throwing exception if
variable not set or non-numeric. Construct default LLHost from getport("PORT")
instead of hardcoded constant.
Change indra/newview/tests/llxmlrpclistener_test.cpp to use commtest_data::
getport("PORT") instead of hardcoded constant. Also use LLSD::with() rather
than older LLSD::insert() syntax.
HOWEVER -- I am irritated to discover that llxmlrpclistener_test IS NOT RUN or
even built by newview/CMakeLists.txt! It's not even commented out -- it's
entirely deleted! I am determined to restore this test. However, as it will
take some fiddling with new link-time dependencies, that will be a separate
commit.

1 files changed, 19 insertions, 1 deletions

diff --git a/indra/llmessage/tests/commtest.h b/indra/llmessage/tests/commtest.h
index 32035783e2..0fef596df2 100644
--- a/indra/llmessage/tests/commtest.h
+++ b/indra/llmessage/tests/commtest.h
@@ -35,6 +35,13 @@
 #include "llhost.h"
 #include "stringize.h"
 #include <string>
+#include <stdexcept>
+#include <boost/lexical_cast.hpp>
+
+struct CommtestError: public std::runtime_error
+{
+    CommtestError(const std::string& what): std::runtime_error(what) {}
+};
 
 /**
  * This struct is shared by a couple of standalone comm tests (ADD_COMM_BUILD_TEST).
@@ -55,13 +62,24 @@ struct commtest_data
         replyPump("reply"),
         errorPump("error"),
         success(false),
-        host("127.0.0.1", 8000),
+        host("127.0.0.1", getport("PORT")),
         server(STRINGIZE("http://" << host.getString() << "/"))
     {
         replyPump.listen("self", boost::bind(&commtest_data::outcome, this, _1, true));
         errorPump.listen("self", boost::bind(&commtest_data::outcome, this, _1, false));
     }
 
+    static int getport(const std::string& var)
+    {
+        const char* port = getenv(var.c_str());
+        if (! port)
+        {
+            throw CommtestError("missing $PORT environment variable");
+        }
+        // This will throw, too, if the value of PORT isn't numeric.
+        return boost::lexical_cast<int>(port);
+    }
+
     bool outcome(const LLSD& _result, bool _success)
     {
 //      std::cout << "commtest_data::outcome(" << _result << ", " << _success << ")\n";