init push

src/sql/engine/expr/ob_expr_chr.cpp

@@ -0,0 +1,163 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+#define USING_LOG_PREFIX SQL_ENG
+
+#include "sql/engine/expr/ob_expr_chr.h"
+#include "sql/session/ob_sql_session_info.h"
+
+#include <string.h>
+#include "lib/oblog/ob_log.h"
+#include "sql/parser/ob_item_type.h"
+
+using namespace oceanbase::common;
+
+namespace oceanbase {
+namespace sql {
+
+ObExprChr::ObExprChr(ObIAllocator& alloc) : ObStringExprOperator(alloc, T_FUN_SYS_CHR, N_CHR, 1)
+{}
+
+ObExprChr::~ObExprChr()
+{}
+
+inline int ObExprChr::calc_result_type1(ObExprResType& type, ObExprResType& text, common::ObExprTypeCtx& type_ctx) const
+{
+  int ret = OB_SUCCESS;
+  const ObSQLSessionInfo* session = type_ctx.get_session();
+  if (OB_ISNULL(session)) {
+    ret = OB_ERR_UNEXPECTED;
+    LOG_WARN("session is NULL", K(ret));
+  } else {
+    if (session->use_static_typing_engine()) {
+      ObSEArray<ObExprResType*, 1, ObNullAllocator> params;
+      OZ(params.push_back(&text));
+      OZ(aggregate_string_type_and_charset_oracle(*session, params, type));
+    } else {
+      type.set_varchar();
+      type.set_collation_level(common::CS_LEVEL_COERCIBLE);
+      type.set_default_collation_type();
+    }
+  }
+  if (OB_SUCC(ret)) {
+    type.set_length(4);
+    type.set_length_semantics(common::LS_BYTE);
+    text.set_calc_type(common::ObDoubleType);
+  }
+  return ret;
+}
+
+int ObExprChr::calc(ObObj& result, const ObObj& text, ObIAllocator& alloc)
+{
+  int ret = OB_SUCCESS;
+  if (text.is_null()) {
+    result.set_null();
+  } else {
+    TYPE_CHECK(text, ObDoubleType);
+    double double_val = text.get_double();
+    ObString str_result;
+    if (OB_FAIL(number2varchar(str_result, double_val, alloc))) {
+      LOG_WARN("fail to convert number 2 varchar", K(ret), K(double_val));
+    } else if (str_result.empty()) {
+      result.set_null();
+    } else {
+      result.set_varchar(str_result);
+    }
+  }
+  return ret;
+}
+
+int ObExprChr::calc_result1(ObObj& result, const ObObj& text, ObExprCtx& expr_ctx) const
+{
+  int ret = OB_SUCCESS;
+  if (OB_ISNULL(expr_ctx.calc_buf_)) {
+    ret = OB_NOT_INIT;
+    LOG_WARN("varchar buffer not init", K(ret));
+  } else if (OB_FAIL(calc(result, text, *expr_ctx.calc_buf_))) {
+    LOG_WARN("fail to calc", K(ret), K(text));
+  } else if (OB_LIKELY(!result.is_null())) {
+    result.set_collation_type(result_type_.get_collation_type());
+    result.set_collation_level(result_type_.get_collation_level());
+  } else {
+  }
+  return ret;
+}
+
+int ObExprChr::number2varchar(ObString& str_result, const double double_val, ObIAllocator& alloc)
+{
+  int ret = OB_SUCCESS;
+  int64_t int_val = static_cast<int64_t>(double_val);
+  // for chr(n), floor(n) in [0, UINT32_MAX]. If floor(n) not satisfy this scope, raise numeric
+  // overflow. If 0 < n < 1, floor(n) also satisfy the scope, but oracle raise nurmeric overflow.
+  if (floor(double_val) < 0 || floor(double_val) > UINT32_MAX || (double_val > 0 && double_val < 1)) {
+    ret = OB_INTEGER_PRECISION_OVERFLOW;
+    str_result.reset();
+  } else {
+    uint32_t num = static_cast<uint32_t>(int_val);
+    int length = 0;
+    if (num & 0xFF000000UL) {
+      length = 4;
+    } else if (num & 0xFF0000UL) {
+      length = 3;
+    } else if (num & 0xFF00UL) {
+      length = 2;
+    } else {
+      length = 1;
+    }
+    char* buf = static_cast<char*>(alloc.alloc(length));
+    if (OB_ISNULL(buf)) {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_ERROR("alloc memory failed", K(ret));
+    } else {
+      for (int i = 0; i < length; ++i) {
+        buf[length - i - 1] = static_cast<char>(num >> (8 * i));
+      }
+      str_result.assign_ptr(buf, static_cast<ObString::obstr_size_t>(length));
+    }
+  }
+  return ret;
+}
+
+int ObExprChr::calc_chr_expr(const ObExpr& expr, ObEvalCtx& ctx, ObDatum& res_datum)
+{
+  int ret = OB_SUCCESS;
+  ObDatum* arg = NULL;
+  if (OB_FAIL(expr.args_[0]->eval(ctx, arg))) {
+    LOG_WARN("eval arg failed", K(ret));
+  } else if (arg->is_null()) {
+    res_datum.set_null();
+  } else {
+    ObExprStrResAlloc res_alloc(expr, ctx);
+    double arg_double = arg->get_double();
+    ObString res_str;
+    if (OB_FAIL(ObExprChr::number2varchar(res_str, arg_double, res_alloc))) {
+      LOG_WARN("number2varchar failed", K(ret), K(arg_double));
+    } else if (res_str.empty()) {
+      res_datum.set_null();
+    } else {
+      res_datum.set_string(res_str);
+    }
+  }
+  return ret;
+}
+
+int ObExprChr::cg_expr(ObExprCGCtx& expr_cg_ctx, const ObRawExpr& raw_expr, ObExpr& rt_expr) const
+{
+  int ret = OB_SUCCESS;
+  UNUSED(expr_cg_ctx);
+  UNUSED(raw_expr);
+  rt_expr.eval_func_ = calc_chr_expr;
+  return ret;
+}
+
+}  // end namespace sql
+}  // end namespace oceanbase