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[toc] / antlr4-cpp-runtime-4.9.2-source / runtime / src / dfa / DFASerializer.cpp

diff --git a/antlr4-cpp-runtime-4.9.2-source/runtime/src/dfa/DFASerializer.cpp b/antlr4-cpp-runtime-4.9.2-source/runtime/src/dfa/DFASerializer.cpp
new file mode 100644 (file)
index 0000000..d27e53f
--- /dev/null
+++ b/antlr4-cpp-runtime-4.9.2-source/runtime/src/dfa/DFASerializer.cpp
@@ -0,0 +1,67 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#include "dfa/DFA.h"
+#include "Vocabulary.h"
+
+#include "dfa/DFASerializer.h"
+
+using namespace antlr4::dfa;
+
+DFASerializer::DFASerializer(const DFA *dfa, const std::vector<std::string>& tokenNames)
+  : DFASerializer(dfa, Vocabulary::fromTokenNames(tokenNames)) {
+}
+
+DFASerializer::DFASerializer(const DFA *dfa, const Vocabulary &vocabulary) : _dfa(dfa), _vocabulary(vocabulary) {
+}
+
+DFASerializer::~DFASerializer() {
+}
+
+std::string DFASerializer::toString() const {
+  if (_dfa->s0 == nullptr) {
+    return "";
+  }
+
+  std::stringstream ss;
+  std::vector<DFAState *> states = _dfa->getStates();
+  for (auto *s : states) {
+    for (size_t i = 0; i < s->edges.size(); i++) {
+      DFAState *t = s->edges[i];
+      if (t != nullptr && t->stateNumber != INT32_MAX) {
+        ss << getStateString(s);
+        std::string label = getEdgeLabel(i);
+        ss << "-" << label << "->" << getStateString(t) << "\n";
+      }
+    }
+  }
+
+  return ss.str();
+}
+
+std::string DFASerializer::getEdgeLabel(size_t i) const {
+  return _vocabulary.getDisplayName(i); // ml: no longer needed -1 as we use a map for edges, without offset.
+}
+
+std::string DFASerializer::getStateString(DFAState *s) const {
+  size_t n = s->stateNumber;
+
+  const std::string baseStateStr = std::string(s->isAcceptState ? ":" : "") + "s" + std::to_string(n) +
+    (s->requiresFullContext ? "^" : "");
+
+  if (s->isAcceptState) {
+    if (!s->predicates.empty()) {
+      std::string buf;
+      for (size_t i = 0; i < s->predicates.size(); i++) {
+        buf.append(s->predicates[i]->toString());
+      }
+      return baseStateStr + "=>" + buf;
+    } else {
+      return baseStateStr + "=>" + std::to_string(s->prediction);
+    }
+  } else {
+    return baseStateStr;
+  }
+}