Limit the length of the file name of the log file for tests

[tberghammer]

Summary

Limit the length of the file name of the log file for tests

If a test have very long name and the compiler specified with (a long) full path then the name of the log file name can exceed 255 characters. This change replace the full compiler path with just the compiler name if the prior would cause a too long file name.

[clayborg]

Looks good.

test/lldbtest.py

def dumpSessionInfo(self):
         dname = os.path.join(os.environ["LLDB_TEST"],
                              os.environ["LLDB_SESSION_DIRNAME"])
         if not os.path.isdir(dname):
             os.mkdir(dname)
         compiler = self.getCompiler()
         if compiler[1] == ':':
             compiler = compiler[2:]
 
-        fname = os.path.join(dname, "%s-%s-%s-%s.log" % (prefix, self.getArchitecture(), "_".join(compiler.split(os.path.sep)), self.id()))
-        with open(fname, "w") as f:
+        fname = "%s-%s-%s-%s.log" % (prefix, self.getArchitecture(), "_".join(compiler.split(os.path.sep)), self.id())
+        if len(fname) > 255:
+            fname = "%s-%s-%s-%s.log" % (prefix, self.getArchitecture(), compiler.split(os.path.sep)[-1], self.id())
+        pname = os.path.join(dname, fname)
+        with open(pname, "w") as f:
             import datetime
             print >> f, "Session info generated @", datetime.datetime.now().ctime()
             print >> f, self.session.getvalue()
             print >> f, "To rerun this test, issue the following command from the 'test' directory:\n"
             print >> f, "./dotest.py %s -v %s %s" % (self.getRunOptions(),
                                                      ('+b' if benchmarks else '-t'),
                                                      self.getRerunArgs())