Init

plugSrc/mysql/build/stmt.go

@@ -0,0 +1,175 @@
+package build
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"math"
+	"strings"
+
+	"errors"
+)
+
+type Stmt struct {
+	ID         uint32
+	Query      string
+	ParamCount uint16
+	FieldCount uint16
+
+	Args []interface{}
+}
+
+func (stmt *Stmt) WriteToText() []byte {
+
+	var buf bytes.Buffer
+
+	str := fmt.Sprintf("预处理编号[%d]: '%s';\n", stmt.ID, stmt.Query)
+	buf.WriteString(str)
+
+	for i := 0; i < int(stmt.ParamCount); i++ {
+		var str string
+		switch stmt.Args[i].(type) {
+		case nil:
+			str = fmt.Sprintf("set @p%v = NULL;\n", i)
+		case []byte:
+			param := string(stmt.Args[i].([]byte))
+			str = fmt.Sprintf("set @p%v = '%s';\n", i, strings.TrimSpace(param))
+		default:
+			str = fmt.Sprintf("set @p%v = %v;\n", i, stmt.Args[i])
+		}
+		buf.WriteString(str)
+	}
+
+	str = fmt.Sprintf("执行预处理[%d]: ", stmt.ID)
+	buf.WriteString(str)
+	for i := 0; i < int(stmt.ParamCount); i++ {
+		if i == 0 {
+			buf.WriteString(" using ")
+		}
+		if i > 0 {
+			buf.WriteString(", ")
+		}
+		str := fmt.Sprintf("@p%v", i)
+		buf.WriteString(str)
+	}
+	buf.WriteString(";\n")
+
+	str = fmt.Sprintf("丢弃预处理[%d];\n", stmt.ID)
+	buf.WriteString(str)
+
+	return buf.Bytes()
+}
+
+func (stmt *Stmt) BindArgs(nullBitmap, paramTypes, paramValues []byte) error {
+
+	args := stmt.Args
+	pos := 0
+
+	var v []byte
+	var n = 0
+	var isNull bool
+	var err error
+
+	for i := 0; i < int(stmt.ParamCount); i++ {
+
+		//判断参数是否为null
+		if nullBitmap[i>>3]&(1<<(uint(i)%8)) > 0 {
+			args[i] = nil
+			continue
+		}
+
+		//参数类型
+		typ := paramTypes[i<<1]
+		unsigned := (paramTypes[(i<<1)+1] & 0x80) > 0
+
+		switch typ {
+		case MYSQL_TYPE_NULL:
+			args[i] = nil
+			continue
+
+		case MYSQL_TYPE_TINY:
+
+			value := paramValues[pos]
+			if unsigned {
+				args[i] = uint8(value)
+			} else {
+				args[i] = int8(value)
+			}
+
+			pos++
+			continue
+
+		case MYSQL_TYPE_SHORT, MYSQL_TYPE_YEAR:
+
+			value := binary.LittleEndian.Uint16(paramValues[pos : pos+2])
+			if unsigned {
+				args[i] = uint16(value)
+			} else {
+				args[i] = int16(value)
+			}
+			pos += 2
+			continue
+
+		case MYSQL_TYPE_INT24, MYSQL_TYPE_LONG:
+
+			value := binary.LittleEndian.Uint32(paramValues[pos : pos+4])
+			if unsigned {
+				args[i] = uint32(value)
+			} else {
+				args[i] = int32(value)
+			}
+			pos += 4
+			continue
+
+		case MYSQL_TYPE_LONGLONG:
+
+			value := binary.LittleEndian.Uint64(paramValues[pos : pos+8])
+			if unsigned {
+				args[i] = value
+			} else {
+				args[i] = int64(value)
+			}
+			pos += 8
+			continue
+
+		case MYSQL_TYPE_FLOAT:
+
+			value := math.Float32frombits(binary.LittleEndian.Uint32(paramValues[pos : pos+4]))
+			args[i] = float32(value)
+			pos += 4
+			continue
+
+		case MYSQL_TYPE_DOUBLE:
+
+			value := math.Float64frombits(binary.LittleEndian.Uint64(paramValues[pos : pos+8]))
+			args[i] = value
+			pos += 8
+			continue
+
+		case MYSQL_TYPE_DECIMAL, MYSQL_TYPE_NEWDECIMAL,
+			MYSQL_TYPE_VARCHAR, MYSQL_TYPE_BIT,
+			MYSQL_TYPE_ENUM, MYSQL_TYPE_SET,
+			MYSQL_TYPE_TINY_BLOB, MYSQL_TYPE_MEDIUM_BLOB, MYSQL_TYPE_LONG_BLOB, MYSQL_TYPE_BLOB,
+			MYSQL_TYPE_VAR_STRING, MYSQL_TYPE_STRING,
+			MYSQL_TYPE_GEOMETRY,
+			MYSQL_TYPE_DATE, MYSQL_TYPE_NEWDATE, MYSQL_TYPE_TIMESTAMP, MYSQL_TYPE_DATETIME, MYSQL_TYPE_TIME:
+
+			v, isNull, n, err = LengthEncodedString(paramValues[pos:])
+			pos += n
+			if err != nil {
+				return err
+			}
+
+			if !isNull {
+				args[i] = v
+				continue
+			} else {
+				args[i] = nil
+				continue
+			}
+		default:
+			return errors.New(fmt.Sprintf("预处理未知类型 %d", typ))
+		}
+	}
+	return nil
+}