ISSUE-112 Fail the glue generator if the second index is out of range

utils/glue_generator_src/CMakeLists.txt

@@ -13,7 +13,7 @@
 # limitations under the License.
 cmake_minimum_required(VERSION 3.0.0)
 
-project(glue_generator LANGUAGES CXX VERSION 0.0.1)
+project(glue_generator VERSION 0.0.1)
 
 # CMake build for OpenPLC glue generator. The glue generator takes
 # generated C code from the MATIEC compiler and then generates necessary

utils/glue_generator_src/glue_generator.cpp

@@ -473,7 +473,9 @@ void generateBottom(ostream& glueVars) {
 })";
 }
 
-void generateBody(istream& locatedVars, ostream& glueVars, md5_byte_t digest[16]) {
+/// Generate the body by parsing the located variables and write into the glue variables.
+/// @return 0 on success, or non-zero on failure.
+uint8_t generateBody(istream& locatedVars, ostream& glueVars, md5_byte_t digest[16]) {
     // We will generate a checksum of the located variables so that
     // we can detect likely changes (not intended to be cryptographically
     // secure). This is only to prevent obvious problems.
@@ -502,6 +504,12 @@ void generateBody(istream& locatedVars, ostream& glueVars, md5_byte_t digest[16]
         uint16_t pos1;
         uint16_t pos2;
         findPositions(iecVar_name, &pos1, &pos2);
+
+        if (pos2 > 7) {
+            cout << "Sub-position of variable " << iecVar_name << " must be in the range 0 to 7";
+            return -1;
+        }
+
         max_index = max(max_index, (int32_t)pos1);
 
         all_vars.push_back(IecVar{ iecVar_name, iecVar_type, pos1, pos2 });
@@ -520,6 +528,8 @@ void generateBody(istream& locatedVars, ostream& glueVars, md5_byte_t digest[16]
 
     // Finish the checksum value
     md5_finish(&md5_state, digest);
+
+    return 0;
 }
 
 void generateChecksum(ostream& glueVars, md5_byte_t digest[16]) {
@@ -576,19 +586,21 @@ int mainImpl(int argc, char const * const *argv) {
         cout << endl;
         return 1;
     }
-    ofstream glueVars(output_file_name, ios::trunc);
-    if (!glueVars.is_open()) {
+    ofstream output_stream(output_file_name, ios::trunc);
+    if (!output_stream.is_open()) {
         cout << "Error opening glue variables file at " << output_file_name;
         cout << endl;
         return 2;
     }
 
-    generateHeader(glueVars);
+    generateHeader(output_stream);
 
     md5_byte_t digest[16];
-    generateBody(locatedVars, glueVars, digest);
-    generateChecksum(glueVars, digest);
-    generateBottom(glueVars);
+    if (!generateBody(locatedVars, output_stream, digest)) {
+        return 1;
+    }
+    generateChecksum(output_stream, digest);
+    generateBottom(output_stream);
 
     return 0;
 }

utils/glue_generator_src/test/glue_generator_test.cpp

@@ -66,8 +66,14 @@ SCENARIO("", "") {
         std::stringstream output_stream;
         md5_byte_t digest[16];
 
+        WHEN("Contains single BOOL at %IX0.8 is invalid index") {
+            std::stringstream input_stream("__LOCATED_VAR(BOOL,__IX0,I,X,0, 8)");
+            auto result = generateBody(input_stream, output_stream, digest);
+            REQUIRE(result != 0);
+        }
+
         WHEN("Contains single BOOL at %IX0") {
-            std::stringstream input_stream("__LOCATED_VAR(BOOL,__IX0,I,X,0)");
+            std::stringstream input_stream("__LOCATED_VAR(BOOL,__IX0_8,I,X,0)");
             generateBody(input_stream, output_stream, digest);
             const char* expected = PREFIX "\tbool_input[0][0] = __IX0;\n" POSTFIX
                 "GlueBoolGroup ___IG0 { .index=0, .values={ __IX0, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, } };\n"