rename StructMapping to StructLayout

2024-08-29 18:56:26 +03:00
parent d0bc679815
commit bcd6f40ddb
5 changed files with 63 additions and 60 deletions
@@ -0,0 +1,202 @@
+#include "StructLayout.hpp"
+
+#include <cstring>
+#include <string.h>
+#include <stdexcept>
+#include <algorithm>
+
+#include "util/data_io.hpp"
+#include "util/stringutil.hpp"
+
+using namespace data;
+
+static_assert(sizeof(float) == sizeof(int32_t));
+static_assert(sizeof(double) == sizeof(int64_t));
+
+StructLayout StructLayout::create(const std::vector<Field>& fields) {
+    std::vector<Field> builtFields = fields;
+    std::unordered_map<std::string, int> indices;
+
+    for (Field& field : builtFields) {
+        field.size = sizeof_type(field.type) * field.elements;
+    }
+    std::sort(builtFields.begin(), builtFields.end(), 
+        [](const Field& a, const Field& b) {
+            return a.size > b.size;
+        }
+    );
+    int offset = 0;
+    for (int i = 0; i < builtFields.size(); i++) {
+        auto& field = builtFields[i];
+        field.offset = offset;
+        indices[field.name] = i;
+        offset += field.size;
+    }
+    return StructLayout(
+        offset, std::move(builtFields), std::move(indices));
+}
+
+const Field& StructLayout::requreField(const std::string& name) const {
+    auto found = indices.find(name);
+    if (found == indices.end()) {
+        throw std::runtime_error("field '"+name+"' does not exist");
+    }
+    return *&fields.at(found->second);
+}
+
+
+template<typename T>
+static void set_int(ubyte* dst, integer_t value) {
+    T out_value = static_cast<T>(value);
+    out_value = dataio::le2h(out_value);
+    *reinterpret_cast<T*>(dst) = out_value;
+}
+
+void StructLayout::setInteger(
+    ubyte* dst, integer_t value, const std::string& name, int index
+) {
+    const auto& field = requreField(name);
+    if (index < 0 || index >= field.elements) {
+        throw std::out_of_range(
+            "index out of bounds [0, "+std::to_string(field.elements)+"]");
+    }
+    auto ptr = dst + field.offset + index * sizeof_type(field.type);
+    switch (field.type) {
+        case FieldType::I8: set_int<int8_t>(ptr, value); break;
+        case FieldType::I16: set_int<int16_t>(ptr, value); break;
+        case FieldType::I32: set_int<int32_t>(ptr, value); break;
+        case FieldType::I64: set_int<int64_t>(ptr, value); break;
+        case FieldType::CHAR: set_int<int8_t>(ptr, value); break;
+        case FieldType::F32:
+        case FieldType::F64:
+            setNumber(dst, static_cast<number_t>(value), name, index);
+            break;
+        default: 
+            throw std::runtime_error("type error");
+    }
+}
+
+void StructLayout::setNumber(
+    ubyte* dst, number_t value, const std::string& name, int index
+) {
+    const auto& field = requreField(name);
+    if (index < 0 || index >= field.elements) {
+        throw std::out_of_range(
+            "index out of bounds [0, "+std::to_string(field.elements)+"]");
+    }
+    auto ptr = dst + field.offset + index * sizeof_type(field.type);
+    switch (field.type) {
+        case FieldType::F32: {
+            float fval = static_cast<float>(value);
+            int32_t ival;
+            std::memcpy(&ival, &fval, sizeof(int32_t));
+            set_int<int32_t>(ptr, ival);
+            break;
+        }
+        case FieldType::F64: {
+            double fval = static_cast<double>(value);
+            int64_t ival;
+            std::memcpy(&ival, &fval, sizeof(int64_t));
+            set_int<int64_t>(ptr, ival);
+            break;
+        }
+        default:
+            throw std::runtime_error("type error");
+    }
+}
+
+size_t StructLayout::setChars(
+    ubyte* dst, std::string_view value, const std::string& name
+) {
+    const auto& field = requreField(name);
+    if (field.type != FieldType::CHAR) {
+        throw std::runtime_error("'char' field type required");
+    }
+    auto ptr = reinterpret_cast<char*>(dst + field.offset);
+    auto size = std::min(value.size(), static_cast<std::size_t>(field.elements));
+    std::memcpy(ptr, value.data(), size);
+    return size;
+}
+
+size_t StructLayout::setUnicode(
+    ubyte* dst, std::string_view value, const std::string& name
+) {
+    const auto& field = requreField(name);
+    if (field.type != FieldType::CHAR) {
+        throw std::runtime_error("'char' field type required");
+    }
+    auto text = std::string_view(value.data(), value.size());
+    size_t size = util::crop_utf8(text, field.elements);
+    auto ptr = reinterpret_cast<char*>(dst + field.offset);
+    std::memcpy(ptr, value.data(), size);
+    return size;
+}
+
+template<typename T>
+static T get_int(const ubyte* src) {
+    return dataio::le2h(*reinterpret_cast<const T*>(src));
+}
+
+integer_t StructLayout::getInteger(
+    const ubyte* src, const std::string& name, int index
+) const {
+    const auto& field = requreField(name);
+    if (index < 0 || index >= field.elements) {
+        throw std::out_of_range(
+            "index out of bounds [0, "+std::to_string(field.elements)+"]");
+    }
+    auto ptr = src + field.offset + index * sizeof_type(field.type);
+    switch (field.type) {
+        case FieldType::I8: return get_int<int8_t>(ptr);
+        case FieldType::I16: return get_int<int16_t>(ptr);
+        case FieldType::I32: return get_int<int32_t>(ptr);
+        case FieldType::I64: return get_int<int64_t>(ptr);
+        case FieldType::CHAR: return get_int<int8_t>(ptr);
+        default:
+            throw std::runtime_error("type error");
+    }
+}
+
+number_t StructLayout::getNumber(
+    const ubyte* src, const std::string& name, int index
+) const {
+    const auto& field = requreField(name);
+    if (index < 0 || index >= field.elements) {
+        throw std::out_of_range(
+            "index out of bounds [0, "+std::to_string(field.elements)+"]");
+    }
+    auto ptr = src + field.offset + index * sizeof_type(field.type);
+    switch (field.type) {
+        case FieldType::F32: {
+            float fval;
+            auto ival = get_int<int32_t>(ptr);
+            std::memcpy(&fval, &ival, sizeof(float));
+            return fval;
+        }
+        case FieldType::F64: {
+            double fval;
+            auto ival = get_int<int64_t>(ptr);
+            std::memcpy(&fval, &ival, sizeof(double));
+            return fval;
+        }
+        case FieldType::I8:
+        case FieldType::I16:
+        case FieldType::I32:
+        case FieldType::I64:
+        case FieldType::CHAR:
+            return getInteger(src, name, index);
+        
+    }
+    throw std::runtime_error("type error");
+}
+
+std::string_view StructLayout::getChars(
+    const ubyte* src, const std::string& name
+) const {
+    const auto& field = requreField(name);
+    if (field.type != FieldType::CHAR) {
+        throw std::runtime_error("'char' field type required");
+    }
+    auto ptr = reinterpret_cast<const char*>(src + field.offset);
+    return std::string_view(ptr, strnlen(ptr, field.elements));
+}