#18

core/dbc_parser.cpp

@@ -19,6 +19,36 @@
 #include <utility>
 
 namespace {
+    // Read through the closing unescaped quote, preserving comment whitespace.
+    void ReadCommentLines(std::ifstream &input, std::string &statement,
+                          std::size_t &lineNumber) {
+        bool inQuote = false;
+        bool escaped = false;
+        std::string part = statement;
+        for (;;) {
+            for (const char character: part) {
+                if (escaped) {
+                    escaped = false;
+                } else if (inQuote && character == '\\') {
+                    escaped = true;
+                } else if (character == '"') {
+                    if (inQuote)
+                        return;
+                    inQuote = true;
+                }
+            }
+            if (!inQuote || !std::getline(input, part))
+                return;
+            ++lineNumber;
+            if (!part.empty() && part.back() == '\r')
+                part.pop_back();
+            statement += '\n';
+            statement += part;
+            // A physical newline cannot escape the next line's first character.
+            escaped = false;
+        }
+    }
+
     DbcDiagnosticCode StatementErrorCode(const std::string &keyword) {
         if (keyword == "SG_MUL_VAL_")
             return DbcDiagnosticCode::UnsupportedStatement;
@@ -59,6 +89,10 @@ DbcParseResult DbcParser::ParseFileWithDiagnostics(const std::string &filePath)
     std::string line;
     while (std::getline(input, line)) {
         ++lineNumber;
+        if (!line.empty() && line.back() == '\r')
+            line.pop_back();
+        const std::string rawLine = line;
+        const std::size_t statementLine = lineNumber;
         line = dbc_detail::TrimText(line);
         if (line.empty())
             continue;
@@ -74,19 +108,24 @@ DbcParseResult DbcParser::ParseFileWithDiagnostics(const std::string &filePath)
             continue; // NS_ lists syntax symbols; BO_, SG_, BS_ and BU_ end the list.
         inNamespace = keyword == "NS_" || keyword == "NS_:";
 
+        if (keyword == "CM_") {
+            line = rawLine;
+            ReadCommentLines(input, line, lineNumber);
+        }
+
         try {
-            context.lineNumber = lineNumber;
+            context.lineNumber = statementLine;
             if (!dispatcher.Dispatch(line, context)) {
                 result.diagnostics.push_back({DbcDiagnosticSeverity::Warning,
                                               DbcDiagnosticCode::UnsupportedStatement,
-                                              filePath, lineNumber,
+                                              filePath, statementLine,
                                               "Unsupported statement '" + keyword +
-                                              "' is ignored; decoding or metadata may be incomplete."});
+                                                      "' is ignored; decoding or metadata may be incomplete."});
             }
         } catch (const std::exception &error) {
             result.diagnostics.push_back({DbcDiagnosticSeverity::Error,
                                           StatementErrorCode(keyword), filePath,
-                                          lineNumber, error.what()});
+                                          statementLine, error.what()});
             return result;
         }
     }
@@ -99,6 +138,7 @@ DbcParseResult DbcParser::ParseFileWithDiagnostics(const std::string &filePath)
     }
 
     try {
+        context.ResolveComments(filePath);
         context.ResolveValueDescriptions(filePath);
         context.ValidateMultiplexing(filePath);
     } catch (const DbcDiagnosticError &error) {