Add Priority::Low and Priority::High

Change-Id: Ia6a8e2adb9671ab585264e0b56871d9324056464
Reviewed-on: http://review.northscale.com:8080/45
Reviewed-by: Dustin Sallings <dustin@spy.net>
Tested-by: Dustin Sallings <dustin@spy.net>

.gitignore

@@ -34,6 +34,7 @@
 /m4/ltsugar.m4
 /m4/ltversion.m4
 /m4/version.m4
+/priority_test
 /stamp-h1
 Makefile
 Makefile.in

Makefile.am

@@ -15,6 +15,7 @@ ep_la_SOURCES = \
                  kvstore.hh \
                  locks.hh \
                  mutex.hh \
+                 priority.hh priority.cc \
                  sqlite-eval.hh sqlite-eval.cc \
                  sqlite-kvstore.cc sqlite-kvstore.hh \
                  sqlite-pst.hh sqlite-pst.cc \
@@ -28,11 +29,14 @@ ep_la_DEPENDENCIES = libsqlite3.la
 libsqlite3_la_SOURCES = embedded/sqlite3.h embedded/sqlite3.c
 libsqlite3_la_CFLAGS = $(AM_CFLAGS) ${NO_WERROR}
 
-check_PROGRAMS=hash_table_test
+check_PROGRAMS=hash_table_test priority_test
 TESTS=${check_PROGRAMS}
 
 hash_table_test_CXXFLAGS = $(AM_CXXFLAGS) -I$(top_srcdir) ${NO_WERROR}
 hash_table_test_SOURCES = t/hash_table_test.cc item.cc
 hash_table_test_DEPENDENCIES = ep.hh item.hh
 
+priority_test_CXXFLAGS = $(AM_CXXFLAGS) -I$(top_srcdir) ${NO_WERROR}
+priority_test_SOURCES = t/priority_test.cc priority.hh priority.cc
+
 test: check-TESTS

priority.cc

@@ -0,0 +1,5 @@
+/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+#include "priority.hh"
+
+const Priority Priority::Low("low");
+const Priority Priority::High("high");

priority.hh

@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+#ifndef PRIORITY_HH
+#define PRIORITY_HH
+
+#include "common.hh"
+
+#include <string>
+
+class Priority {
+public:
+    static const Priority Low;
+    static const Priority High;
+
+    bool operator==(const Priority &other) const {
+        return (&other == this);
+    }
+
+    bool operator<(const Priority &other) const {
+        return this == &Low;
+    }
+
+    bool operator>(const Priority &other) const {
+        return this == &High;
+    }
+
+    const std::string &toString() const {
+        return name;
+    }
+
+private:
+    Priority(const char *nm) : name(nm) { };
+    std::string name;
+    DISALLOW_COPY_AND_ASSIGN(Priority);
+};
+
+#endif

t/priority_test.cc

@@ -0,0 +1,19 @@
+/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+#include "priority.hh"
+#undef NDEBUG
+#include <assert.h>
+
+int main(int argc, char **argv) {
+   (void)argc; (void)argv;
+
+   assert(Priority::Low < Priority::High);
+   assert(!(Priority::High < Priority::Low));
+   assert(Priority::High > Priority::Low);
+   assert(!(Priority::Low > Priority::High));
+   assert(!(Priority::Low == Priority::High));
+   assert(!(Priority::High == Priority::Low));
+   assert(Priority::Low == Priority::Low);
+   assert(Priority::High == Priority::High);
+
+   return 0;
+}