Add llvm fuzzer for CPDF_PSEngine

core/fpdfapi/fpdf_page/cpdf_psengine.h

Index: core/fpdfapi/fpdf_page/cpdf_psengine.h
diff --git a/core/fpdfapi/fpdf_page/cpdf_psengine.h b/core/fpdfapi/fpdf_page/cpdf_psengine.h
new file mode 100644
index 0000000000000000000000000000000000000000..fc8badbe6d82e552097727e12452c4f1ff380409
--- /dev/null
+++ b/core/fpdfapi/fpdf_page/cpdf_psengine.h
@@ -0,0 +1,100 @@
+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#ifndef CORE_FPDFAPI_FPDF_PAGE_CPDF_PSENGINE_H_
+#define CORE_FPDFAPI_FPDF_PAGE_CPDF_PSENGINE_H_
+
+#include <memory>
+#include <vector>
+
+#include "core/fxcrt/include/fx_system.h"
+
+class CPDF_PSEngine;
+class CPDF_PSOP;
+class CPDF_SimpleParser;
+
+enum PDF_PSOP {
+  PSOP_ADD,
+  PSOP_SUB,
+  PSOP_MUL,
+  PSOP_DIV,
+  PSOP_IDIV,
+  PSOP_MOD,
+  PSOP_NEG,
+  PSOP_ABS,
+  PSOP_CEILING,
+  PSOP_FLOOR,
+  PSOP_ROUND,
+  PSOP_TRUNCATE,
+  PSOP_SQRT,
+  PSOP_SIN,
+  PSOP_COS,
+  PSOP_ATAN,
+  PSOP_EXP,
+  PSOP_LN,
+  PSOP_LOG,
+  PSOP_CVI,
+  PSOP_CVR,
+  PSOP_EQ,
+  PSOP_NE,
+  PSOP_GT,
+  PSOP_GE,
+  PSOP_LT,
+  PSOP_LE,
+  PSOP_AND,
+  PSOP_OR,
+  PSOP_XOR,
+  PSOP_NOT,
+  PSOP_BITSHIFT,
+  PSOP_TRUE,
+  PSOP_FALSE,
+  PSOP_IF,
+  PSOP_IFELSE,
+  PSOP_POP,
+  PSOP_EXCH,
+  PSOP_DUP,
+  PSOP_COPY,
+  PSOP_INDEX,
+  PSOP_ROLL,
+  PSOP_PROC,
+  PSOP_CONST
+};
+
+constexpr uint32_t PSENGINE_STACKSIZE = 100;
+
+class CPDF_PSProc {
+ public:
+  CPDF_PSProc();
+  ~CPDF_PSProc();
+
+  FX_BOOL Parse(CPDF_SimpleParser* parser);
+  FX_BOOL Execute(CPDF_PSEngine* pEngine);
+
+ private:
+  std::vector<std::unique_ptr<CPDF_PSOP>> m_Operators;
+};
+
+class CPDF_PSEngine {
+ public:
+  CPDF_PSEngine();
+  ~CPDF_PSEngine();
+
+  FX_BOOL Parse(const FX_CHAR* str, int size);
+  FX_BOOL Execute();
+  FX_BOOL DoOperator(PDF_PSOP op);
+  void Reset() { m_StackCount = 0; }
+  void Push(FX_FLOAT value);
+  void Push(int value) { Push((FX_FLOAT)value); }
+  FX_FLOAT Pop();
+  uint32_t GetStackSize() const { return m_StackCount; }
+
+ private:
+  FX_FLOAT m_Stack[PSENGINE_STACKSIZE];
+  uint32_t m_StackCount;
+  CPDF_PSProc m_MainProc;
+};
+
+#endif  // CORE_FPDFAPI_FPDF_PAGE_CPDF_PSENGINE_H_