fix some overflows

bit/decode.go

@@ -99,6 +99,26 @@ func ReadVarInt32(r Reader) uint32 {
 	return uint32(x)
 }
 
+// reads a 32bit varint
+func ReadVarInt16(r Reader) uint16 {
+	var (
+		x     uint64
+		b     uint64
+		shift uint
+	)
+	for ; shift < 16; shift += 7 {
+		b = r.ReadBits(8)
+		if r.Err() != nil {
+			return 0
+		}
+		x |= b & 0x7f << shift
+		if b&0x80 == 0 {
+			return uint16(x)
+		}
+	}
+	return uint16(x)
+}
+
 func ReadBool(r Reader) bool {
 	return r.ReadBits(1) != 0
 }

ent/array.go

@@ -50,7 +50,7 @@ type array_t struct {
 }
 
 func (t *array_t) nü() value       { return array{t: t, slots: make([]value, t.count)} }
-func (t array_t) typeName() string { return fmt.Sprintf("array:%s", t.elem.typeName()) }
+func (t array_t) typeName() string { return fmt.Sprintf("%s[%d]", t.elem.typeName(), t.count) }
 
 type array struct {
 	t     *array_t

ent/atoms.go

@@ -48,11 +48,7 @@ type uint8_v uint8
 
 func (v uint8_v) tÿpe() tÿpe { return uint8_t }
 func (v *uint8_v) read(r bit.Reader) error {
-	u := bit.ReadVarInt(r)
-	if u > 1<<8-1 {
-		return fmt.Errorf("uint8 overflow: %d", u)
-	}
-	*v = uint8_v(u)
+	*v = uint8_v(r.ReadBits(8))
 	return r.Err()
 }
 
@@ -75,11 +71,7 @@ type uint16_v uint16
 
 func (v uint16_v) tÿpe() tÿpe { return uint16_t }
 func (v *uint16_v) read(r bit.Reader) error {
-	u := bit.ReadVarInt(r)
-	if u > 1<<16-1 {
-		return fmt.Errorf("uint16 overflow: %d", u)
-	}
-	*v = uint16_v(u)
+	*v = uint16_v(bit.ReadVarInt16(r))
 	return r.Err()
 }
 

ent/env.go

@@ -2,6 +2,7 @@ package ent
 
 import (
 	"github.com/golang/protobuf/proto"
+	"os"
 	"strconv"
 
 	"github.com/jordanorelli/hyperstone/bit"
@@ -178,7 +179,8 @@ func (e *Env) syncBaselineTable(t *stbl.Table) {
 		Debug.Printf("selections: %v", selections)
 		for _, s := range selections {
 			if err := s.fillSlots(ent, r); err != nil {
-				Debug.Printf("unable to fill selection %s for %s: %v", s, className, err)
+				Debug.Printf("syncBaseline fill error: %v", err)
+				os.Exit(1)
 			}
 		}
 	}

ent/generic.go

@@ -2,6 +2,7 @@ package ent
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 
 	"github.com/jordanorelli/hyperstone/bit"
@@ -80,7 +81,7 @@ func (t cutl_vector_t) typeName() string {
 }
 
 type cutl_vector struct {
-	t     tÿpe
+	t     *cutl_vector_t
 	slots []value
 }
 
@@ -98,3 +99,14 @@ func (v cutl_vector) String() string {
 	}
 	return fmt.Sprintf("%s(%d)%v", v.t.typeName(), len(v.slots), v.slots)
 }
+
+func (v *cutl_vector) slotType(int) tÿpe     { return v.t.elem }
+func (v *cutl_vector) slotName(n int) string { return strconv.Itoa(n) }
+func (v *cutl_vector) setSlotValue(slot int, val value) {
+	if slot == len(v.slots) {
+		v.slots = append(v.slots, val)
+	} else {
+		v.slots[slot] = val
+	}
+}
+func (v *cutl_vector) getSlotValue(slot int) value { return v.slots[slot] }

ent/selection.go

@@ -32,7 +32,7 @@ func (s selection) fillSlotsIter(offset int, dest slotted, path string, r bit.Re
 	case 1:
 		v := dest.slotType(slot).nü()
 		if err := v.read(r); err != nil {
-			return fmt.Errorf("unable to fill selection: %v", err)
+			return fmt.Errorf("unable to fill selection %v for %s.%s (%s): %v", s, path, dest.slotName(slot), dest.slotType(slot).typeName(), err)
 		}
 		old := dest.getSlotValue(slot)
 		dest.setSlotValue(slot, v)