Decompile fn_17631 (MatchLexicon)

Batch #842 by ragnarok-clanker: 0 byte-identical, 1 confirmed by peer review.

- fn_17631 MatchLexicon: logic confirmed by peer review

Reviewed-by: ragnarok-clanker
Adds to the build: Source/Utility/LexiconMatcher.cpp

Source/Utility/LexiconMatcher.cpp

@@ -0,0 +1,68 @@
+#include "Utility/LexiconMatcher.h"
+
+#include <cstdint>
+
+// FUNCTION: fn_17631
+int __stdcall MatchLexicon(const unsigned char* data, int, const unsigned char* text, const unsigned char* end, int) {
+  if (*text == 0) {
+    return 1000;
+  }
+
+  int accepted = 0;
+  int matched = 0;
+  bool failed = false;
+  const unsigned char* entry = data;
+  while (text < end && !failed) {
+    if ((*entry & 0x40) != 0) {
+      return matched;
+    }
+
+    std::uint32_t offset = (static_cast<std::uint32_t>(entry[0] & 0x3F) << 16) |
+                           (static_cast<std::uint32_t>(entry[1]) << 8) | entry[2];
+    entry += 3;
+    const unsigned char* candidate = data + offset;
+    const unsigned int count = *candidate;
+    if (count < 0x20 && candidate[1] == *text) {
+      ++offset;
+      for (unsigned int index = 0; index < count; ++index) {
+        if (data[offset++] != *text) {
+          failed = true;
+          break;
+        }
+
+        ++matched;
+        ++text;
+        const unsigned char marker = data[offset];
+        if (marker < 0x20) {
+          if ((marker & 2) != 0) {
+            accepted = matched;
+          }
+
+          if ((marker & 4) != 0) {
+            entry = data + offset + 1;
+            break;
+          }
+
+          ++offset;
+        }
+      }
+    } else if (count >= *text) {
+      if (count != *text) {
+        return accepted;
+      }
+
+      ++matched;
+      entry = candidate + 1;
+      ++text;
+      if (static_cast<signed char>(*entry) < 0) {
+        accepted = matched;
+      }
+    }
+
+    if (*text == 0) {
+      return accepted;
+    }
+  }
+
+  return accepted;
+}

Source/Utility/LexiconMatcher.h

@@ -0,0 +1,6 @@
+#ifndef RAGNAROK_SOURCE_UTILITY_LEXICONMATCHER_H
+#define RAGNAROK_SOURCE_UTILITY_LEXICONMATCHER_H
+
+int __stdcall MatchLexicon(const unsigned char* data, int mode, const unsigned char* text, const unsigned char* end, int options);
+
+#endif

compile.json

@@ -585,6 +585,7 @@
   "Source/Utility/Base64.cpp": 0,
   "Source/Utility/GuidParse.cpp": 0,
   "Source/Utility/LexiconBoundary.cpp": 0,
+  "Source/Utility/LexiconMatcher.cpp": 0,
   "Source/Utility/LexiconSerializer.cpp": 0,
   "Source/Utility/MD5.cpp": 0,
   "Source/Utility/Math/AffineLookAt.cpp": 0,