From 19ae359e9e3ebe14181289a08480c66f15755af4 Mon Sep 17 00:00:00 2001
From: Jack Christensen <jack@jackchristensen.com>
Date: Fri, 31 Dec 2021 17:03:31 -0600
Subject: [PATCH] Add binary scan plans for int2

---
 pgtype/int2_codec.go         |  43 +++---
 pgtype/int_scan_plans.go     | 248 +++++++++++++++++++++++++++++++++++
 pgtype/int_scan_plans.go.erb | 135 +++++++++++++++++++
 3 files changed, 405 insertions(+), 21 deletions(-)

diff --git a/pgtype/int2_codec.go b/pgtype/int2_codec.go
index 17c335a6..d436346c 100644
--- a/pgtype/int2_codec.go
+++ b/pgtype/int2_codec.go
@@ -2,7 +2,6 @@ package pgtype
 
 import (
 	"database/sql/driver"
-	"encoding/binary"
 	"fmt"
 	"math"
 	"strconv"
@@ -50,6 +49,28 @@ func (Int2Codec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 	switch format {
 	case BinaryFormatCode:
+		switch target.(type) {
+		case *int8:
+			return scanPlanBinaryInt2ToInt8{}
+		case *int16:
+			return scanPlanBinaryInt2ToInt16{}
+		case *int32:
+			return scanPlanBinaryInt2ToInt32{}
+		case *int64:
+			return scanPlanBinaryInt2ToInt64{}
+		case *int:
+			return scanPlanBinaryInt2ToInt{}
+		case *uint8:
+			return scanPlanBinaryInt2ToUint8{}
+		case *uint16:
+			return scanPlanBinaryInt2ToUint16{}
+		case *uint32:
+			return scanPlanBinaryInt2ToUint32{}
+		case *uint64:
+			return scanPlanBinaryInt2ToUint64{}
+		case *uint:
+			return scanPlanBinaryInt2ToUint{}
+		}
 	case TextFormatCode:
 		switch target.(type) {
 		case *int8:
@@ -111,23 +132,3 @@ func (c Int2Codec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 	}
 	return n, nil
 }
-
-type scanPlanBinaryInt2ToInt16 struct{}
-
-func (scanPlanBinaryInt2ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	if src == nil {
-		return fmt.Errorf("cannot scan null into %T", dst)
-	}
-
-	if len(src) != 2 {
-		return fmt.Errorf("invalid length for int2: %v", len(src))
-	}
-
-	p, ok := (dst).(*int16)
-	if !ok {
-		return ErrScanTargetTypeChanged
-	}
-
-	*p = int16(binary.BigEndian.Uint16(src))
-	return nil
-}
diff --git a/pgtype/int_scan_plans.go b/pgtype/int_scan_plans.go
index e7fce506..1694e021 100644
--- a/pgtype/int_scan_plans.go
+++ b/pgtype/int_scan_plans.go
@@ -1,7 +1,9 @@
 package pgtype
 
 import (
+	"encoding/binary"
 	"fmt"
+	"math"
 	"strconv"
 )
 
@@ -214,3 +216,249 @@ func (scanPlanTextAnyToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, sr
 	*p = uint(n)
 	return nil
 }
+
+type scanPlanBinaryInt2ToInt8 struct{}
+
+func (scanPlanBinaryInt2ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for int2: %v", len(src))
+	}
+
+	p, ok := (dst).(*int8)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int16(binary.BigEndian.Uint16(src))
+	if n < math.MinInt8 {
+		return fmt.Errorf("%d is less than minimum value for int8", n)
+	} else if n > math.MaxInt8 {
+		return fmt.Errorf("%d is greater than maximum value for int8", n)
+	}
+
+	*p = int8(n)
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToUint8 struct{}
+
+func (scanPlanBinaryInt2ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for uint2: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint8)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int16(binary.BigEndian.Uint16(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint8", n)
+	}
+
+	if n > math.MaxUint8 {
+		return fmt.Errorf("%d is greater than maximum value for uint8", n)
+	}
+
+	*p = uint8(n)
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToInt16 struct{}
+
+func (scanPlanBinaryInt2ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for int2: %v", len(src))
+	}
+
+	p, ok := (dst).(*int16)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	*p = int16(binary.BigEndian.Uint16(src))
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToUint16 struct{}
+
+func (scanPlanBinaryInt2ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for uint2: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint16)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int16(binary.BigEndian.Uint16(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint16", n)
+	}
+
+	*p = uint16(n)
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToInt32 struct{}
+
+func (scanPlanBinaryInt2ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for int2: %v", len(src))
+	}
+
+	p, ok := (dst).(*int32)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	*p = int32(binary.BigEndian.Uint16(src))
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToUint32 struct{}
+
+func (scanPlanBinaryInt2ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for uint2: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint32)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int16(binary.BigEndian.Uint16(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint32", n)
+	}
+
+	*p = uint32(n)
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToInt64 struct{}
+
+func (scanPlanBinaryInt2ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for int2: %v", len(src))
+	}
+
+	p, ok := (dst).(*int64)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	*p = int64(binary.BigEndian.Uint16(src))
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToUint64 struct{}
+
+func (scanPlanBinaryInt2ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for uint2: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint64)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int16(binary.BigEndian.Uint16(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint64", n)
+	}
+
+	*p = uint64(n)
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToInt struct{}
+
+func (scanPlanBinaryInt2ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for int2: %v", len(src))
+	}
+
+	p, ok := (dst).(*int)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	*p = int(binary.BigEndian.Uint16(src))
+
+	return nil
+}
+
+type scanPlanBinaryInt2ToUint struct{}
+
+func (scanPlanBinaryInt2ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != 2 {
+		return fmt.Errorf("invalid length for uint2: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int64(binary.BigEndian.Uint16(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint", n)
+	}
+
+	*p = uint(n)
+
+	return nil
+}
diff --git a/pgtype/int_scan_plans.go.erb b/pgtype/int_scan_plans.go.erb
index abdd1329..448453f1 100644
--- a/pgtype/int_scan_plans.go.erb
+++ b/pgtype/int_scan_plans.go.erb
@@ -54,3 +54,138 @@ func (scanPlanTextAnyToUint<%= type_suffix %>) Scan(ci *ConnInfo, oid uint32, fo
 	return nil
 }
 <% end %>
+
+<% [
+  [16, 8],
+  [16, 16],
+  [16, 32],
+  [16, 64],
+].each do |src_bit_size, dst_bit_size| %>
+<% src_byte_size = src_bit_size / 8 %>
+type scanPlanBinaryInt<%= src_byte_size %>ToInt<%= dst_bit_size %> struct{}
+
+func (scanPlanBinaryInt<%= src_byte_size %>ToInt<%= dst_bit_size %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != <%= src_byte_size %> {
+		return fmt.Errorf("invalid length for int<%= src_byte_size %>: %v", len(src))
+	}
+
+	p, ok := (dst).(*int<%= dst_bit_size %>)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+  <% if dst_bit_size < src_bit_size %>
+	n := int<%= src_bit_size %>(binary.BigEndian.Uint<%= src_bit_size %>(src))
+	if n < math.MinInt<%= dst_bit_size %> {
+		return fmt.Errorf("%d is less than minimum value for int<%= dst_bit_size %>", n)
+	} else if n > math.MaxInt<%= dst_bit_size %> {
+		return fmt.Errorf("%d is greater than maximum value for int<%= dst_bit_size %>", n)
+	}
+
+	*p = int<%= dst_bit_size %>(n)
+  <% else %>
+	*p = int<%= dst_bit_size %>(binary.BigEndian.Uint<%= src_bit_size %>(src))
+  <% end %>
+
+	return nil
+}
+
+type scanPlanBinaryInt<%= src_byte_size %>ToUint<%= dst_bit_size %> struct{}
+
+func (scanPlanBinaryInt<%= src_byte_size %>ToUint<%= dst_bit_size %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != <%= src_byte_size %> {
+		return fmt.Errorf("invalid length for uint<%= src_byte_size %>: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint<%= dst_bit_size %>)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int<%= src_bit_size %>(binary.BigEndian.Uint<%= src_bit_size %>(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint<%= dst_bit_size %>", n)
+	}
+  <% if dst_bit_size < src_bit_size %>
+	if n > math.MaxUint<%= dst_bit_size %> {
+		return fmt.Errorf("%d is greater than maximum value for uint<%= dst_bit_size %>", n)
+	}
+  <% end %>
+	*p = uint<%= dst_bit_size %>(n)
+
+	return nil
+}
+<% end %>
+
+<% [16].each do |src_bit_size| %>
+<% src_byte_size = src_bit_size / 8 %>
+type scanPlanBinaryInt<%= src_byte_size %>ToInt struct{}
+
+func (scanPlanBinaryInt<%= src_byte_size %>ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != <%= src_byte_size %> {
+		return fmt.Errorf("invalid length for int<%= src_byte_size %>: %v", len(src))
+	}
+
+	p, ok := (dst).(*int)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+  <% if 32 < src_bit_size %>
+	n := int64(binary.BigEndian.Uint<%= src_bit_size %>(src))
+	if n < math.MinInt {
+		return fmt.Errorf("%d is less than minimum value for int", n)
+	} else if n > math.MaxInt {
+		return fmt.Errorf("%d is greater than maximum value for int", n)
+	}
+
+	*p = int(n)
+  <% else %>
+	*p = int(binary.BigEndian.Uint<%= src_bit_size %>(src))
+  <% end %>
+
+	return nil
+}
+
+type scanPlanBinaryInt<%= src_byte_size %>ToUint struct{}
+
+func (scanPlanBinaryInt<%= src_byte_size %>ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	if src == nil {
+		return fmt.Errorf("cannot scan null into %T", dst)
+	}
+
+	if len(src) != <%= src_byte_size %> {
+		return fmt.Errorf("invalid length for uint<%= src_byte_size %>: %v", len(src))
+	}
+
+	p, ok := (dst).(*uint)
+	if !ok {
+		return ErrScanTargetTypeChanged
+	}
+
+	n := int64(binary.BigEndian.Uint<%= src_bit_size %>(src))
+	if n < 0 {
+		return fmt.Errorf("%d is less than minimum value for uint", n)
+	}
+  <% if 32 < src_bit_size %>
+	if uint64(n) > math.MaxUint {
+		return fmt.Errorf("%d is greater than maximum value for uint", n)
+	}
+  <% end %>
+	*p = uint(n)
+
+	return nil
+}
+<% end %>