Merge pull request #650 from denizevrenci/simplify_cpp_generator

tmontgomery · web-flow · commit 2841f628d803 · 2019-03-13T13:23:13.000-07:00
Simplifications and improvements on C++ generator
diff --git a/sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/cpp/CppGenerator.java b/sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/cpp/CppGenerator.java
@@ -203,6 +203,10 @@ private static void generateGroupClassHeader(
             indent + "    std::uint64_t m_offset;\n" +
             indent + "    std::uint64_t m_actingVersion;\n" +
             indent + "    %2$s m_dimensions;\n\n" +
+            indent + "    std::uint64_t *sbePositionPtr() SBE_NOEXCEPT\n" +
+            indent + "    {\n" +
+            indent + "        return m_positionPtr;\n" +
+            indent + "    }\n\n" +
             indent + "public:\n",
             formatClassName(groupName), dimensionsClassName));
 
@@ -269,13 +273,17 @@ private static void generateGroupClassHeader(
             indent + "    {\n" +
             indent + "        return *m_positionPtr;\n" +
             indent + "    }\n\n" +
-            indent + "    void sbePosition(const std::uint64_t position)\n" +
+            indent + "    std::uint64_t sbeCheckPosition(const std::uint64_t position)\n" +
             indent + "    {\n" +
             indent + "        if (SBE_BOUNDS_CHECK_EXPECT((position > m_bufferLength), false))\n" +
             indent + "        {\n" +
-            indent + "             throw std::runtime_error(\"buffer too short [E100]\");\n" +
+            indent + "            throw std::runtime_error(\"buffer too short [E100]\");\n" +
             indent + "        }\n" +
-            indent + "        *m_positionPtr = position;\n" +
+            indent + "        return position;\n" +
+            indent + "    }\n\n" +
+            indent + "    void sbePosition(const std::uint64_t position)\n" +
+            indent + "    {\n" +
+            indent + "        *m_positionPtr = sbeCheckPosition(position);\n" +
             indent + "    }\n\n" +
             indent + "    inline std::uint64_t count() const SBE_NOEXCEPT\n" +
             indent + "    {\n" +
@@ -346,7 +354,7 @@ private static CharSequence generateGroupProperty(
         sb.append(String.format("\n" +
             indent + "    inline %1$s &%2$s()\n" +
             indent + "    {\n" +
-            indent + "        m_%2$s.wrapForDecode(m_buffer, m_positionPtr, m_actingVersion, m_bufferLength);\n" +
+            indent + "        m_%2$s.wrapForDecode(m_buffer, sbePositionPtr(), m_actingVersion, m_bufferLength);\n" +
             indent + "        return m_%2$s;\n" +
             indent + "    }\n",
             className,
@@ -356,7 +364,7 @@ private static CharSequence generateGroupProperty(
             indent + "    %1$s &%2$sCount(const %3$s count)\n" +
             indent + "    {\n" +
             indent + "        m_%2$s.wrapForEncode(" +
-            "m_buffer, count, m_positionPtr, m_actingVersion, m_bufferLength);\n" +
+            "m_buffer, count, sbePositionPtr(), m_actingVersion, m_bufferLength);\n" +
             indent + "        return m_%2$s;\n" +
             indent + "    }\n",
             className,
@@ -1514,18 +1522,6 @@ private CharSequence generateFixedFlyweightCode(final String className, final in
             "    std::uint64_t m_bufferLength;\n" +
             "    std::uint64_t m_offset = 0;\n" +
             "    std::uint64_t m_actingVersion;\n\n" +
-            "    inline void reset(char *buffer, const std::uint64_t offset, const std::uint64_t bufferLength," +
-            " const std::uint64_t actingVersion)\n" +
-            "    {\n" +
-            "        if (SBE_BOUNDS_CHECK_EXPECT(((offset + %2$s) > bufferLength), false))\n" +
-            "        {\n" +
-            "            throw std::runtime_error(\"buffer too short for flyweight [E107]\");\n" +
-            "        }\n\n" +
-            "        m_buffer = buffer;\n" +
-            "        m_bufferLength = bufferLength;\n" +
-            "        m_offset = offset;\n" +
-            "        m_actingVersion = actingVersion;\n" +
-            "    }\n\n" +
             "public:\n" +
             "    enum MetaAttribute\n" +
             "    {\n" +
@@ -1542,15 +1538,38 @@ private CharSequence generateFixedFlyweightCode(final String className, final in
             "        std::uint64_t uint_value;\n" +
             "    };\n\n" +
             "    %1$s() = default;\n\n" +
-            "    %1$s(char *buffer, const std::uint64_t bufferLength, const std::uint64_t actingVersion)\n" +
+            "    %1$s(\n" +
+            "        char *buffer,\n" +
+            "        const std::uint64_t offset,\n" +
+            "        const std::uint64_t bufferLength,\n" +
+            "        const std::uint64_t actingVersion) :\n" +
+            "        m_buffer(buffer),\n" +
+            "        m_bufferLength(bufferLength),\n" +
+            "        m_offset(offset),\n" +
+            "        m_actingVersion(actingVersion)\n" +
+            "    {\n" +
+            "        if (SBE_BOUNDS_CHECK_EXPECT(((m_offset + %2$s) > m_bufferLength), false))\n" +
+            "        {\n" +
+            "            throw std::runtime_error(\"buffer too short for flyweight [E107]\");\n" +
+            "        }\n" +
+            "    }\n\n" +
+            "    %1$s(\n" +
+            "        char *buffer,\n" +
+            "        const std::uint64_t bufferLength,\n" +
+            "        const std::uint64_t actingVersion) :\n" +
+            "        %1$s(buffer, 0, bufferLength, actingVersion)\n" +
+            "    {\n" +
+            "    }\n\n" +
+            "    %1$s(\n" +
+            "        char *buffer,\n" +
+            "        const std::uint64_t bufferLength) :\n" +
+            "        %1$s(buffer, 0, bufferLength, sbeSchemaVersion())\n" +
             "    {\n" +
-            "        reset(buffer, 0, bufferLength, actingVersion);\n" +
             "    }\n\n" +
             "    %1$s &wrap(char *buffer, const std::uint64_t offset, const std::uint64_t actingVersion," +
             " const std::uint64_t bufferLength)\n" +
             "    {\n" +
-            "        reset(buffer, offset, bufferLength, actingVersion);\n" +
-            "        return *this;\n" +
+            "        return *this = %1$s(buffer, offset, bufferLength, actingVersion);\n" +
             "    }\n\n" +
             "    static SBE_CONSTEXPR std::uint64_t encodedLength() SBE_NOEXCEPT\n" +
             "    {\n" +
@@ -1592,23 +1611,27 @@ private static CharSequence generateConstructorsAndOperators(final String classN
     {
         return String.format(
             "    %1$s() = default;\n\n" +
-            "    %1$s(char *buffer, const std::uint64_t bufferLength)\n" +
-            "    {\n" +
-            "        reset(buffer, 0, bufferLength, sbeBlockLength(), sbeSchemaVersion());\n" +
-            "    }\n\n" +
-            "    %1$s(char *buffer, const std::uint64_t bufferLength, const std::uint64_t actingBlockLength," +
-            " const std::uint64_t actingVersion)\n" +
+            "    %1$s(\n" +
+            "        char *buffer,\n" +
+            "        const std::uint64_t offset,\n" +
+            "        const std::uint64_t bufferLength,\n" +
+            "        const std::uint64_t actingBlockLength,\n" +
+            "        const std::uint64_t actingVersion) :\n" +
+            "        m_buffer(buffer),\n" +
+            "        m_bufferLength(bufferLength),\n" +
+            "        m_offset(offset),\n" +
+            "        m_position(sbeCheckPosition(offset + actingBlockLength)),\n" +
+            "        m_actingVersion(actingVersion)\n" +
             "    {\n" +
-            "        reset(buffer, 0, bufferLength, actingBlockLength, actingVersion);\n" +
             "    }\n\n" +
-            "    %1$s(const %1$s& codec) SBE_NOEXCEPT\n" +
+            "    %1$s(char *buffer, const std::uint64_t bufferLength) :\n" +
+            "        %1$s(buffer, 0, bufferLength, sbeBlockLength(), sbeSchemaVersion())\n" +
             "    {\n" +
-            "        reset(codec);\n" +
             "    }\n\n" +
-            "    %1$s& operator=(const %1$s& codec) SBE_NOEXCEPT\n" +
+            "    %1$s(char *buffer, const std::uint64_t bufferLength, const std::uint64_t actingBlockLength," +
+            " const std::uint64_t actingVersion) :\n" +
+            "        %1$s(buffer, 0, bufferLength, actingBlockLength, actingVersion)\n" +
             "    {\n" +
-            "        reset(codec);\n" +
-            "        return *this;\n" +
             "    }\n\n",
             className);
     }
@@ -1625,32 +1648,12 @@ private CharSequence generateMessageFlyweightCode(final String className, final
             "private:\n" +
             "    char *m_buffer = nullptr;\n" +
             "    std::uint64_t m_bufferLength = 0;\n" +
-            "    std::uint64_t *m_positionPtr;\n" +
             "    std::uint64_t m_offset = 0;\n" +
             "    std::uint64_t m_position;\n" +
-            "    std::uint64_t m_actingBlockLength;\n" +
             "    std::uint64_t m_actingVersion;\n\n" +
-            "    inline void reset(\n" +
-            "        char *buffer, const std::uint64_t offset, const std::uint64_t bufferLength,\n" +
-            "        const std::uint64_t actingBlockLength, const std::uint64_t actingVersion)\n" +
-            "    {\n" +
-            "        m_buffer = buffer;\n" +
-            "        m_offset = offset;\n" +
-            "        m_bufferLength = bufferLength;\n" +
-            "        m_actingBlockLength = actingBlockLength;\n" +
-            "        m_actingVersion = actingVersion;\n" +
-            "        m_positionPtr = &m_position;\n" +
-            "        sbePosition(offset + m_actingBlockLength);\n" +
-            "    }\n\n" +
-            "    inline void reset(const %10$s& codec) SBE_NOEXCEPT\n" +
+            "    inline std::uint64_t *sbePositionPtr() SBE_NOEXCEPT\n" +
             "    {\n" +
-            "        m_buffer = codec.m_buffer;\n" +
-            "        m_offset = codec.m_offset;\n" +
-            "        m_bufferLength = codec.m_bufferLength;\n" +
-            "        m_actingBlockLength = codec.m_actingBlockLength;\n" +
-            "        m_actingVersion = codec.m_actingVersion;\n" +
-            "        m_positionPtr = &m_position;\n" +
-            "        m_position = codec.m_position;\n" +
+            "        return &m_position;\n" +
             "    }\n\n" +
             "public:\n\n" +
             "    enum MetaAttribute\n" +
@@ -1694,10 +1697,9 @@ private CharSequence generateMessageFlyweightCode(final String className, final
             "    }\n\n" +
             "    %10$s &wrapForEncode(char *buffer, const std::uint64_t offset, const std::uint64_t bufferLength)\n" +
             "    {\n" +
-            "        reset(buffer, offset, bufferLength, sbeBlockLength(), sbeSchemaVersion());\n" +
-            "        return *this;\n" +
+            "        return *this = %10$s(buffer, offset, bufferLength, sbeBlockLength(), sbeSchemaVersion());\n" +
             "    }\n\n" +
-            "    %10$s &wrapAndApplyHeader( " +
+            "    %10$s &wrapAndApplyHeader(" +
             "char *buffer, const std::uint64_t offset, const std::uint64_t bufferLength)\n" +
             "    {\n" +
             "        MessageHeader hdr(buffer + offset, bufferLength, sbeSchemaVersion());\n\n" +
@@ -1706,28 +1708,34 @@ private CharSequence generateMessageFlyweightCode(final String className, final
             "            .templateId(sbeTemplateId())\n" +
             "            .schemaId(sbeSchemaId())\n" +
             "            .version(sbeSchemaVersion());\n\n" +
-            "        reset(buffer + offset + MessageHeader::encodedLength(), 0, bufferLength, sbeBlockLength(), " +
-            "sbeSchemaVersion());\n" +
-            "        return *this;\n" +
+            "        return *this = %10$s(\n" +
+            "            buffer + offset + MessageHeader::encodedLength(),\n" +
+            "            0,\n" +
+            "            bufferLength - MessageHeader::encodedLength(),\n" +
+            "            sbeBlockLength()\n," +
+            "            sbeSchemaVersion());\n" +
             "    }\n\n" +
             "    %10$s &wrapForDecode(\n" +
             "         char *buffer, const std::uint64_t offset, const std::uint64_t actingBlockLength,\n" +
             "         const std::uint64_t actingVersion, const std::uint64_t bufferLength)\n" +
             "    {\n" +
-            "        reset(buffer, offset, bufferLength, actingBlockLength, actingVersion);\n" +
-            "        return *this;\n" +
+            "        return *this = %10$s(buffer, offset, bufferLength, actingBlockLength, actingVersion);\n" +
             "    }\n\n" +
             "    std::uint64_t sbePosition() const SBE_NOEXCEPT\n" +
             "    {\n" +
             "        return m_position;\n" +
             "    }\n\n" +
-            "    void sbePosition(const std::uint64_t position)\n" +
+            "    std::uint64_t sbeCheckPosition(const std::uint64_t position)\n" +
             "    {\n" +
             "        if (SBE_BOUNDS_CHECK_EXPECT((position > m_bufferLength), false))\n" +
             "        {\n" +
             "            throw std::runtime_error(\"buffer too short [E100]\");\n" +
             "        }\n" +
-            "        m_position = position;\n" +
+            "        return position;\n" +
+            "    }\n\n" +
+            "    void sbePosition(const std::uint64_t position)\n" +
+            "    {\n" +
+            "        m_position = sbeCheckPosition(position);\n" +
             "    }\n\n" +
             "    std::uint64_t encodedLength() const SBE_NOEXCEPT\n" +
             "    {\n" +
