1 files changed, 117 insertions, 0 deletions
diff --git a/src/sksl/lex/RegexNode.cpp b/src/sksl/lex/RegexNode.cpp
new file mode 100644
index 0000000000..8915c60c44
--- /dev/null
+++ b/src/sksl/lex/RegexNode.cpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "RegexNode.h"
+
+#include "NFA.h"
+
+std::vector<int> RegexNode::createStates(NFA* nfa, const std::vector<int>& accept) const {
+    std::vector<int> result;
+    switch (fKind) {
+        case kChar_Kind:
+            result.push_back(nfa->addState(NFAState(fPayload.fChar, accept)));
+            break;
+        case kCharset_Kind: {
+            std::vector<bool> chars;
+            for (const RegexNode& child : fChildren) {
+                if (child.fKind == kChar_Kind) {
+                    while (chars.size() <= (size_t) child.fPayload.fChar) {
+                        chars.push_back(false);
+                    }
+                    chars[child.fPayload.fChar] = true;
+                } else {
+                    ASSERT(child.fKind == kRange_Kind);
+                    while (chars.size() <= (size_t) child.fChildren[1].fPayload.fChar) {
+                        chars.push_back(false);
+                    }
+                    for (char c = child.fChildren[0].fPayload.fChar;
+                         c <= child.fChildren[1].fPayload.fChar;
+                         ++c) {
+                        chars[c] = true;
+                    }
+                }
+            }
+            result.push_back(nfa->addState(NFAState(fPayload.fBool, chars, accept)));
+            break;
+        }
+        case kConcat_Kind: {
+            std::vector<int> right = fChildren[1].createStates(nfa, accept);
+            result = fChildren[0].createStates(nfa, right);
+            break;
+        }
+        case kDot_Kind:
+            result.push_back(nfa->addState(NFAState(NFAState::kDot_Kind, accept)));
+            break;
+        case kOr_Kind: {
+            std::vector<int> states = fChildren[0].createStates(nfa, accept);
+            result.insert(result.end(), states.begin(), states.end());
+            states = fChildren[1].createStates(nfa, accept);
+            result.insert(result.end(), states.begin(), states.end());
+            break;
+        }
+        case kPlus_Kind: {
+            std::vector<int> next = accept;
+            std::vector<int> placeholder;
+            int id = nfa->addState(NFAState(placeholder));
+            next.push_back(id);
+            result = fChildren[0].createStates(nfa, next);
+            nfa->fStates[id] = NFAState(result);
+            break;
+        }
+        case kQuestion_Kind:
+            result = fChildren[0].createStates(nfa, accept);
+            result.insert(result.end(), accept.begin(), accept.end());
+            break;
+        case kRange_Kind:
+            ABORT("unreachable");
+        case kStar_Kind: {
+            std::vector<int> next = accept;
+            std::vector<int> placeholder;
+            int id = nfa->addState(NFAState(placeholder));
+            next.push_back(id);
+            result = fChildren[0].createStates(nfa, next);
+            result.insert(result.end(), accept.begin(), accept.end());
+            nfa->fStates[id] = NFAState(result);
+            break;
+        }
+    }
+    return result;
+}
+
+std::string RegexNode::description() const {
+    switch (fKind) {
+        case kChar_Kind:
+            return std::string(1, fPayload.fChar);
+        case kCharset_Kind: {
+            std::string result("[");
+            if (fPayload.fBool) {
+                result += "^";
+            }
+            for (const RegexNode& c : fChildren) {
+                result += c.description();
+            }
+            result += "]";
+            return result;
+        }
+        case kConcat_Kind:
+            return fChildren[0].description() + fChildren[1].description();
+        case kDot_Kind:
+            return ".";
+        case kOr_Kind:
+            return "(" + fChildren[0].description() + "|" + fChildren[1].description() + ")";
+        case kPlus_Kind:
+            return fChildren[0].description() + "+";
+        case kQuestion_Kind:
+            return fChildren[0].description() + "?";
+        case kRange_Kind:
+            return fChildren[0].description() + "-" + fChildren[1].description();
+        case kStar_Kind:
+            return fChildren[0].description() + "*";
+        default:
+            return "<" + std::to_string(fKind) + ">";
+    }
+}