Initial commit of prepstmt, selects, record sets

This is full of holes, but all the basics are covered.

1 files changed, 99 insertions, 0 deletions

diff --git a/lib/input/mysqlRecordSet.cpp b/lib/input/mysqlRecordSet.cpp
new file mode 100644
index 0000000..51be15f
--- /dev/null
+++ b/lib/input/mysqlRecordSet.cpp
@@ -0,0 +1,99 @@
+#include "mysqlRecordSet.h"
+#include "mysqlBindings.h"
+#include "mysqlStmt.h"
+#include <cstdint>
+#include <dbTypes.h>
+#include <helpers.h>
+#include <stdexcept>
+#include <string_view>
+#include <utility>
+// IWYU pragma: no_include <ext/alloc_traits.h>
+
+namespace MyGrate::Input {
+	MySQLRecordSet::MySQLRecordSet(StmtPtr s) :
+		stmt {std::move(s)}, stmtres {nullptr, nullptr}, fields(mysql_stmt_field_count(stmt.get())),
+		extras(fields.size())
+	{
+		auto getBind = [](const MYSQL_FIELD & f, MYSQL_BIND & b) -> std::unique_ptr<ResultData> {
+			switch (f.type) {
+				case MYSQL_TYPE_DECIMAL:
+				case MYSQL_TYPE_NEWDECIMAL:
+				case MYSQL_TYPE_DOUBLE:
+					return std::make_unique<ResultDataT<double>>(b, f);
+				case MYSQL_TYPE_FLOAT:
+					return std::make_unique<ResultDataT<float>>(b, f);
+				case MYSQL_TYPE_TINY:
+					return std::make_unique<ResultDataT<int8_t>>(b, f);
+				case MYSQL_TYPE_SHORT:
+				case MYSQL_TYPE_YEAR:
+					return std::make_unique<ResultDataT<int16_t>>(b, f);
+				case MYSQL_TYPE_LONG:
+				case MYSQL_TYPE_INT24:
+					return std::make_unique<ResultDataT<int32_t>>(b, f);
+				case MYSQL_TYPE_LONGLONG:
+					return std::make_unique<ResultDataT<int64_t>>(b, f);
+				case MYSQL_TYPE_NULL:
+					return std::make_unique<ResultDataT<std::nullptr_t>>(b, f);
+				case MYSQL_TYPE_TIMESTAMP:
+				case MYSQL_TYPE_TIMESTAMP2:
+				case MYSQL_TYPE_DATETIME:
+				case MYSQL_TYPE_DATETIME2:
+					return std::make_unique<ResultDataTime<DateTime>>(b, f);
+				case MYSQL_TYPE_TIME:
+				case MYSQL_TYPE_TIME2:
+					return std::make_unique<ResultDataTime<Time>>(b, f);
+				case MYSQL_TYPE_DATE:
+				case MYSQL_TYPE_NEWDATE:
+					return std::make_unique<ResultDataTime<Date>>(b, f);
+				case MYSQL_TYPE_VARCHAR:
+				case MYSQL_TYPE_VAR_STRING:
+				case MYSQL_TYPE_STRING:
+				case MYSQL_TYPE_JSON:
+				case MYSQL_TYPE_ENUM:
+					return std::make_unique<ResultDataT<std::string_view>>(b, f);
+				case MYSQL_TYPE_TINY_BLOB:
+				case MYSQL_TYPE_MEDIUM_BLOB:
+				case MYSQL_TYPE_LONG_BLOB:
+				case MYSQL_TYPE_BLOB:
+					return std::make_unique<ResultDataT<Blob>>(b, f);
+				case MAX_NO_FIELD_TYPES:
+				case MYSQL_TYPE_BIT:
+				case MYSQL_TYPE_SET:
+				case MYSQL_TYPE_GEOMETRY:;
+			}
+			throw std::runtime_error("Unsupported column type");
+		};
+		ResPtr meta {mysql_stmt_result_metadata(stmt.get()), mysql_free_result};
+		const auto fieldDefs = mysql_fetch_fields(meta.get());
+		verify<std::runtime_error>(fieldDefs, "Fetch fields");
+		for (std::size_t i = 0; i < fields.size(); i += 1) {
+			extras[i] = getBind(fieldDefs[i], fields[i]);
+		}
+		verify<std::runtime_error>(!mysql_stmt_bind_result(stmt.get(), fields.data()), "Store result error");
+		verify<std::runtime_error>(!mysql_stmt_store_result(stmt.get()), "Store result error");
+		stmtres = {stmt.get(), mysql_stmt_free_result};
+		verify<std::runtime_error>(!mysql_stmt_fetch(stmt.get()), "Fetch");
+	}
+
+	std::size_t
+	MySQLRecordSet::rows() const
+	{
+		return mysql_stmt_num_rows(stmt.get());
+	}
+
+	std::size_t
+	MySQLRecordSet::columns() const
+	{
+		return fields.size();
+	}
+
+	DbValue
+	MySQLRecordSet::at(std::size_t row, std::size_t col) const
+	{
+		mysql_stmt_data_seek(stmt.get(), row);
+		if (extras[col]->null) {
+			return nullptr;
+		}
+		return extras[col]->getValue();
+	}
+}