Rewrite to use a custom class that that just writes a bare string to …

…the header
ecmwf · Aug 1, 2024 · 7978720 · 7978720
1 parent 15bc01f
commit 7978720
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Showing 4 changed files with 54 additions and 10 deletions.
diff --git a/src/odc/codec/Constant.cc b/src/odc/codec/Constant.cc
@@ -23,6 +23,7 @@ namespace codec {
 namespace {
     core::IntegerCodecBuilder<CodecConstant> constantBuilder;
     core::CodecBuilder<CodecConstantString> constantStringBuilder;
+    core::CodecBuilder<CodecLongConstantString> LongConstantStringBuilder;
 }
 
 //----------------------------------------------------------------------------------------------------------------------

diff --git a/src/odc/codec/Constant.h b/src/odc/codec/Constant.h
@@ -16,6 +16,7 @@
 #define odc_core_codec_Constant_H
 
 #include "odc/core/Codec.h"
+#include "odc/codec/String.h"
 
 namespace odc {
 namespace codec {
@@ -74,6 +75,25 @@ class CodecConstantString : public CodecConstant<ByteOrder, double> {
     void save(core::DataStream<ByteOrder>& ds) override;
 };
 
+template<typename ByteOrder>
+class CodecLongConstantString : public CodecChars<ByteOrder> {
+
+public: // methods
+    constexpr static const char* codec_name() { return "long_constant_string"; }
+    CodecLongConstantString(api::ColumnType type) : CodecChars<ByteOrder>(type, codec_name()) {};
+    ~CodecLongConstantString() override {}
+
+private: // methods
+    unsigned char* encode(unsigned char* p, const double& d) override;
+    void decode(double* out) override;
+    void skip() override;
+
+    size_t numStrings() const override { return 1; }
+
+    void load(core::DataStream<ByteOrder>& ds) override;
+    void save(core::DataStream<ByteOrder>& ds) override;
+};
+
 //----------------------------------------------------------------------------------------------------------------------
 
 // Implementation of Constant
@@ -151,6 +171,39 @@ void CodecConstantString<ByteOrder>::print(std::ostream& s) const {
 
 //----------------------------------------------------------------------------------------------------------------------
 
+// Implementation of LongConstantString
+
+template <typename ByteOrder>
+unsigned char* CodecLongConstantString<ByteOrder>::encode(unsigned char* p, const double&) {
+    return p;
+}
+
+template <typename ByteOrder>
+void CodecLongConstantString<ByteOrder>::decode(double* out) {
+    ::memset(out, 0, this->decodedSizeDoubles_*sizeof(double));
+    ::memcpy(reinterpret_cast<char*>(out), &this->strings_[0][0], std::min(this->strings_[0].length(), this->decodedSizeDoubles_*sizeof(double)));
+}
+
+template <typename ByteOrder>
+void CodecLongConstantString<ByteOrder>::skip() {}
+
+template <typename ByteOrder>
+void CodecLongConstantString<ByteOrder>::load(core::DataStream<ByteOrder>& ds) {
+    core::DataStreamCodec<ByteOrder>::load(ds);
+    std::string s;
+    ds.read(s);
+    this->decodedSizeDoubles_ = ((s.length()-1) / sizeof(double)) +1;
+    this->strings_.push_back(s);
+}
+
+template <typename ByteOrder>
+void CodecLongConstantString<ByteOrder>::save(core::DataStream<ByteOrder>& ds) {
+    core::DataStreamCodec<ByteOrder>::save(ds);
+    ds.write(this->strings_[0]);
+}
+
+//----------------------------------------------------------------------------------------------------------------------
+
 } // namespace codec
 } // namespace odc
 

diff --git a/src/odc/codec/String.cc b/src/odc/codec/String.cc
@@ -21,7 +21,6 @@ namespace codec {
 
 namespace {
     core::CodecBuilder<CodecChars> charsBuilder;
-    core::CodecBuilder<CodecLongConstantString> LongConstantStringBuilder;
     core::CodecBuilder<CodecInt8String> int8StringBuilder;
     core::CodecBuilder<CodecInt16String> int16StringBuilder;
 }

diff --git a/src/odc/codec/String.h b/src/odc/codec/String.h
@@ -210,15 +210,6 @@ class IntStringCodecBase : public CodecChars<ByteOrder> {
 
 //----------------------------------------------------------------------------------------------------------------------
 
-// This class uses the same machinery as CodecInt8String/CodecInt16String etc but it only ever stores one string in the header
-// CodecZeroBitInteger just doesn't encode any data and always returns index 0 when decoding.
-template<typename ByteOrder>
-struct CodecLongConstantString : public IntStringCodecBase<ByteOrder, CodecZeroBitInteger<ByteOrder, int64_t, CodecLongConstantString<ByteOrder>>> {
-    constexpr static const char* codec_name() { return "long_constant_string"; }
-    CodecLongConstantString(api::ColumnType type) : IntStringCodecBase<ByteOrder, CodecZeroBitInteger<ByteOrder, int64_t, CodecLongConstantString<ByteOrder>>>(type, codec_name()) {}
-    ~CodecLongConstantString() override {}
-};
-
 template<typename ByteOrder>
 struct CodecInt8String : public IntStringCodecBase<ByteOrder, CodecInt8<ByteOrder, int64_t>> {
     constexpr static const char* codec_name() { return "int8_string"; }