IMP-267 Add version() function.

be/src/exprs/CMakeLists.txt

@@ -33,6 +33,7 @@ add_library(Exprs
   timestamp-functions.cc
   timestamp-literal.cc
   timezone_db.cc
+  utility-functions.cc
 )
 
 target_link_libraries(Exprs

be/src/exprs/expr-test.cc

@@ -26,6 +26,7 @@
 #include "codegen/llvm-codegen.h"
 #include "util/cpu-info.h"
 #include "util/disk-info.h"
+#include "util/debug-util.h"
 
 using namespace llvm;
 using namespace std;
@@ -1118,6 +1119,8 @@ TEST_F(ExprTest, StringFunctions) {
   // First param contains comma.
   TestValue("find_in_set('abc,def', 'abc,ad,,ade,cde,')", TYPE_INT, 0);
 
+  TestStringValue("version()", GetVersionString());
+
   // TODO: tests with NULL arguments, currently we can't parse them
   // inside function calls.
   // e.g.   TestValue("length(NULL)", TYPE_INT, NULL);

be/src/exprs/expr.h

@@ -245,6 +245,7 @@ class Expr {
   friend class StringFunctions;
   friend class TimestampFunctions;
   friend class ConditionalFunctions;
+  friend class UtilityFunctions;
   friend class CaseExpr;
   friend class InPredicate;
   friend class FunctionCall;

be/src/exprs/utility-functions.cc

@@ -0,0 +1,19 @@
+// Copyright (c) 2011 Cloudera, Inc. All rights reserved.
+
+#include "exprs/utility-functions.h"
+#include "exprs/function-call.h"
+#include "exprs/expr.h"
+#include "util/debug-util.h"
+#include "runtime/tuple-row.h"
+
+using namespace std;
+
+namespace impala {
+
+void* UtilityFunctions::Version(Expr* e, TupleRow* row) {
+  DCHECK_EQ(e->GetNumChildren(), 0);
+  e->result_.SetStringVal(GetVersionString());
+  return &e->result_.string_val;
+}
+
+}

be/src/exprs/utility-functions.h

@@ -0,0 +1,20 @@
+// Copyright (c) 2011 Cloudera, Inc. All rights reserved.
+
+#ifndef IMPALA_EXPRS_UTILITY_FUNCTIONS_H
+#define IMPALA_EXPRS_UTILITY_FUNCTIONS_H
+
+namespace impala {
+
+class Expr;
+class OpcodeRegistry;
+class TupleRow;
+
+class UtilityFunctions {
+ public:
+  // Implementation of the version() function. Returns the version string.  
+  static void* Version(Expr* e, TupleRow* row);
+};
+
+}
+
+#endif

common/function-registry/gen_opcodes.py

@@ -67,6 +67,7 @@ cc_registry_preamble = '\
 #include "exprs/string-functions.h"\n\
 #include "exprs/timestamp-functions.h"\n\
 #include "exprs/conditional-functions.h"\n\
+#include "exprs/utility-functions.h"\n\
 #include "opcode/functions.h"\n\
 \n\
 namespace impala { \n\

common/function-registry/impala_functions.py

@@ -106,6 +106,7 @@ functions = [
         'StringFunctions::ParseUrl', ['parse_url']],
   ['String_Parse_Url', 'STRING', ['STRING', 'STRING', 'STRING'], \
         'StringFunctions::ParseUrlKey', ['parse_url']],
+  ['Utility_Version', 'STRING', [], 'UtilityFunctions::Version', ['version']],
 
 # Timestamp Functions
   ['Unix_Timestamp', 'INT', ['TIMESTAMP'], \