Adding upstream version 1.17.13.upstream/1.17.13upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 599 insertions, 0 deletions

diff --git a/src/database/sql/convert.go b/src/database/sql/convert.go
new file mode 100644
index 0000000..b966ef9
--- /dev/null
+++ b/src/database/sql/convert.go
@@ -0,0 +1,599 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Type conversions for Scan.
+
+package sql
+
+import (
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"time"
+	"unicode"
+	"unicode/utf8"
+)
+
+var errNilPtr = errors.New("destination pointer is nil") // embedded in descriptive error
+
+func describeNamedValue(nv *driver.NamedValue) string {
+	if len(nv.Name) == 0 {
+		return fmt.Sprintf("$%d", nv.Ordinal)
+	}
+	return fmt.Sprintf("with name %q", nv.Name)
+}
+
+func validateNamedValueName(name string) error {
+	if len(name) == 0 {
+		return nil
+	}
+	r, _ := utf8.DecodeRuneInString(name)
+	if unicode.IsLetter(r) {
+		return nil
+	}
+	return fmt.Errorf("name %q does not begin with a letter", name)
+}
+
+// ccChecker wraps the driver.ColumnConverter and allows it to be used
+// as if it were a NamedValueChecker. If the driver ColumnConverter
+// is not present then the NamedValueChecker will return driver.ErrSkip.
+type ccChecker struct {
+	cci  driver.ColumnConverter
+	want int
+}
+
+func (c ccChecker) CheckNamedValue(nv *driver.NamedValue) error {
+	if c.cci == nil {
+		return driver.ErrSkip
+	}
+	// The column converter shouldn't be called on any index
+	// it isn't expecting. The final error will be thrown
+	// in the argument converter loop.
+	index := nv.Ordinal - 1
+	if c.want <= index {
+		return nil
+	}
+
+	// First, see if the value itself knows how to convert
+	// itself to a driver type. For example, a NullString
+	// struct changing into a string or nil.
+	if vr, ok := nv.Value.(driver.Valuer); ok {
+		sv, err := callValuerValue(vr)
+		if err != nil {
+			return err
+		}
+		if !driver.IsValue(sv) {
+			return fmt.Errorf("non-subset type %T returned from Value", sv)
+		}
+		nv.Value = sv
+	}
+
+	// Second, ask the column to sanity check itself. For
+	// example, drivers might use this to make sure that
+	// an int64 values being inserted into a 16-bit
+	// integer field is in range (before getting
+	// truncated), or that a nil can't go into a NOT NULL
+	// column before going across the network to get the
+	// same error.
+	var err error
+	arg := nv.Value
+	nv.Value, err = c.cci.ColumnConverter(index).ConvertValue(arg)
+	if err != nil {
+		return err
+	}
+	if !driver.IsValue(nv.Value) {
+		return fmt.Errorf("driver ColumnConverter error converted %T to unsupported type %T", arg, nv.Value)
+	}
+	return nil
+}
+
+// defaultCheckNamedValue wraps the default ColumnConverter to have the same
+// function signature as the CheckNamedValue in the driver.NamedValueChecker
+// interface.
+func defaultCheckNamedValue(nv *driver.NamedValue) (err error) {
+	nv.Value, err = driver.DefaultParameterConverter.ConvertValue(nv.Value)
+	return err
+}
+
+// driverArgsConnLocked converts arguments from callers of Stmt.Exec and
+// Stmt.Query into driver Values.
+//
+// The statement ds may be nil, if no statement is available.
+//
+// ci must be locked.
+func driverArgsConnLocked(ci driver.Conn, ds *driverStmt, args []interface{}) ([]driver.NamedValue, error) {
+	nvargs := make([]driver.NamedValue, len(args))
+
+	// -1 means the driver doesn't know how to count the number of
+	// placeholders, so we won't sanity check input here and instead let the
+	// driver deal with errors.
+	want := -1
+
+	var si driver.Stmt
+	var cc ccChecker
+	if ds != nil {
+		si = ds.si
+		want = ds.si.NumInput()
+		cc.want = want
+	}
+
+	// Check all types of interfaces from the start.
+	// Drivers may opt to use the NamedValueChecker for special
+	// argument types, then return driver.ErrSkip to pass it along
+	// to the column converter.
+	nvc, ok := si.(driver.NamedValueChecker)
+	if !ok {
+		nvc, ok = ci.(driver.NamedValueChecker)
+	}
+	cci, ok := si.(driver.ColumnConverter)
+	if ok {
+		cc.cci = cci
+	}
+
+	// Loop through all the arguments, checking each one.
+	// If no error is returned simply increment the index
+	// and continue. However if driver.ErrRemoveArgument
+	// is returned the argument is not included in the query
+	// argument list.
+	var err error
+	var n int
+	for _, arg := range args {
+		nv := &nvargs[n]
+		if np, ok := arg.(NamedArg); ok {
+			if err = validateNamedValueName(np.Name); err != nil {
+				return nil, err
+			}
+			arg = np.Value
+			nv.Name = np.Name
+		}
+		nv.Ordinal = n + 1
+		nv.Value = arg
+
+		// Checking sequence has four routes:
+		// A: 1. Default
+		// B: 1. NamedValueChecker 2. Column Converter 3. Default
+		// C: 1. NamedValueChecker 3. Default
+		// D: 1. Column Converter 2. Default
+		//
+		// The only time a Column Converter is called is first
+		// or after NamedValueConverter. If first it is handled before
+		// the nextCheck label. Thus for repeats tries only when the
+		// NamedValueConverter is selected should the Column Converter
+		// be used in the retry.
+		checker := defaultCheckNamedValue
+		nextCC := false
+		switch {
+		case nvc != nil:
+			nextCC = cci != nil
+			checker = nvc.CheckNamedValue
+		case cci != nil:
+			checker = cc.CheckNamedValue
+		}
+
+	nextCheck:
+		err = checker(nv)
+		switch err {
+		case nil:
+			n++
+			continue
+		case driver.ErrRemoveArgument:
+			nvargs = nvargs[:len(nvargs)-1]
+			continue
+		case driver.ErrSkip:
+			if nextCC {
+				nextCC = false
+				checker = cc.CheckNamedValue
+			} else {
+				checker = defaultCheckNamedValue
+			}
+			goto nextCheck
+		default:
+			return nil, fmt.Errorf("sql: converting argument %s type: %v", describeNamedValue(nv), err)
+		}
+	}
+
+	// Check the length of arguments after conversion to allow for omitted
+	// arguments.
+	if want != -1 && len(nvargs) != want {
+		return nil, fmt.Errorf("sql: expected %d arguments, got %d", want, len(nvargs))
+	}
+
+	return nvargs, nil
+
+}
+
+// convertAssign is the same as convertAssignRows, but without the optional
+// rows argument.
+func convertAssign(dest, src interface{}) error {
+	return convertAssignRows(dest, src, nil)
+}
+
+// convertAssignRows copies to dest the value in src, converting it if possible.
+// An error is returned if the copy would result in loss of information.
+// dest should be a pointer type. If rows is passed in, the rows will
+// be used as the parent for any cursor values converted from a
+// driver.Rows to a *Rows.
+func convertAssignRows(dest, src interface{}, rows *Rows) error {
+	// Common cases, without reflect.
+	switch s := src.(type) {
+	case string:
+		switch d := dest.(type) {
+		case *string:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = []byte(s)
+			return nil
+		case *RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = append((*d)[:0], s...)
+			return nil
+		}
+	case []byte:
+		switch d := dest.(type) {
+		case *string:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = string(s)
+			return nil
+		case *interface{}:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = cloneBytes(s)
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = cloneBytes(s)
+			return nil
+		case *RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s
+			return nil
+		}
+	case time.Time:
+		switch d := dest.(type) {
+		case *time.Time:
+			*d = s
+			return nil
+		case *string:
+			*d = s.Format(time.RFC3339Nano)
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = []byte(s.Format(time.RFC3339Nano))
+			return nil
+		case *RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = s.AppendFormat((*d)[:0], time.RFC3339Nano)
+			return nil
+		}
+	case decimalDecompose:
+		switch d := dest.(type) {
+		case decimalCompose:
+			return d.Compose(s.Decompose(nil))
+		}
+	case nil:
+		switch d := dest.(type) {
+		case *interface{}:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		case *[]byte:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		case *RawBytes:
+			if d == nil {
+				return errNilPtr
+			}
+			*d = nil
+			return nil
+		}
+	// The driver is returning a cursor the client may iterate over.
+	case driver.Rows:
+		switch d := dest.(type) {
+		case *Rows:
+			if d == nil {
+				return errNilPtr
+			}
+			if rows == nil {
+				return errors.New("invalid context to convert cursor rows, missing parent *Rows")
+			}
+			rows.closemu.Lock()
+			*d = Rows{
+				dc:          rows.dc,
+				releaseConn: func(error) {},
+				rowsi:       s,
+			}
+			// Chain the cancel function.
+			parentCancel := rows.cancel
+			rows.cancel = func() {
+				// When Rows.cancel is called, the closemu will be locked as well.
+				// So we can access rs.lasterr.
+				d.close(rows.lasterr)
+				if parentCancel != nil {
+					parentCancel()
+				}
+			}
+			rows.closemu.Unlock()
+			return nil
+		}
+	}
+
+	var sv reflect.Value
+
+	switch d := dest.(type) {
+	case *string:
+		sv = reflect.ValueOf(src)
+		switch sv.Kind() {
+		case reflect.Bool,
+			reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
+			reflect.Float32, reflect.Float64:
+			*d = asString(src)
+			return nil
+		}
+	case *[]byte:
+		sv = reflect.ValueOf(src)
+		if b, ok := asBytes(nil, sv); ok {
+			*d = b
+			return nil
+		}
+	case *RawBytes:
+		sv = reflect.ValueOf(src)
+		if b, ok := asBytes([]byte(*d)[:0], sv); ok {
+			*d = RawBytes(b)
+			return nil
+		}
+	case *bool:
+		bv, err := driver.Bool.ConvertValue(src)
+		if err == nil {
+			*d = bv.(bool)
+		}
+		return err
+	case *interface{}:
+		*d = src
+		return nil
+	}
+
+	if scanner, ok := dest.(Scanner); ok {
+		return scanner.Scan(src)
+	}
+
+	dpv := reflect.ValueOf(dest)
+	if dpv.Kind() != reflect.Ptr {
+		return errors.New("destination not a pointer")
+	}
+	if dpv.IsNil() {
+		return errNilPtr
+	}
+
+	if !sv.IsValid() {
+		sv = reflect.ValueOf(src)
+	}
+
+	dv := reflect.Indirect(dpv)
+	if sv.IsValid() && sv.Type().AssignableTo(dv.Type()) {
+		switch b := src.(type) {
+		case []byte:
+			dv.Set(reflect.ValueOf(cloneBytes(b)))
+		default:
+			dv.Set(sv)
+		}
+		return nil
+	}
+
+	if dv.Kind() == sv.Kind() && sv.Type().ConvertibleTo(dv.Type()) {
+		dv.Set(sv.Convert(dv.Type()))
+		return nil
+	}
+
+	// The following conversions use a string value as an intermediate representation
+	// to convert between various numeric types.
+	//
+	// This also allows scanning into user defined types such as "type Int int64".
+	// For symmetry, also check for string destination types.
+	switch dv.Kind() {
+	case reflect.Ptr:
+		if src == nil {
+			dv.Set(reflect.Zero(dv.Type()))
+			return nil
+		}
+		dv.Set(reflect.New(dv.Type().Elem()))
+		return convertAssignRows(dv.Interface(), src, rows)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		if src == nil {
+			return fmt.Errorf("converting NULL to %s is unsupported", dv.Kind())
+		}
+		s := asString(src)
+		i64, err := strconv.ParseInt(s, 10, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetInt(i64)
+		return nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		if src == nil {
+			return fmt.Errorf("converting NULL to %s is unsupported", dv.Kind())
+		}
+		s := asString(src)
+		u64, err := strconv.ParseUint(s, 10, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetUint(u64)
+		return nil
+	case reflect.Float32, reflect.Float64:
+		if src == nil {
+			return fmt.Errorf("converting NULL to %s is unsupported", dv.Kind())
+		}
+		s := asString(src)
+		f64, err := strconv.ParseFloat(s, dv.Type().Bits())
+		if err != nil {
+			err = strconvErr(err)
+			return fmt.Errorf("converting driver.Value type %T (%q) to a %s: %v", src, s, dv.Kind(), err)
+		}
+		dv.SetFloat(f64)
+		return nil
+	case reflect.String:
+		if src == nil {
+			return fmt.Errorf("converting NULL to %s is unsupported", dv.Kind())
+		}
+		switch v := src.(type) {
+		case string:
+			dv.SetString(v)
+			return nil
+		case []byte:
+			dv.SetString(string(v))
+			return nil
+		}
+	}
+
+	return fmt.Errorf("unsupported Scan, storing driver.Value type %T into type %T", src, dest)
+}
+
+func strconvErr(err error) error {
+	if ne, ok := err.(*strconv.NumError); ok {
+		return ne.Err
+	}
+	return err
+}
+
+func cloneBytes(b []byte) []byte {
+	if b == nil {
+		return nil
+	}
+	c := make([]byte, len(b))
+	copy(c, b)
+	return c
+}
+
+func asString(src interface{}) string {
+	switch v := src.(type) {
+	case string:
+		return v
+	case []byte:
+		return string(v)
+	}
+	rv := reflect.ValueOf(src)
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return strconv.FormatInt(rv.Int(), 10)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return strconv.FormatUint(rv.Uint(), 10)
+	case reflect.Float64:
+		return strconv.FormatFloat(rv.Float(), 'g', -1, 64)
+	case reflect.Float32:
+		return strconv.FormatFloat(rv.Float(), 'g', -1, 32)
+	case reflect.Bool:
+		return strconv.FormatBool(rv.Bool())
+	}
+	return fmt.Sprintf("%v", src)
+}
+
+func asBytes(buf []byte, rv reflect.Value) (b []byte, ok bool) {
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return strconv.AppendInt(buf, rv.Int(), 10), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return strconv.AppendUint(buf, rv.Uint(), 10), true
+	case reflect.Float32:
+		return strconv.AppendFloat(buf, rv.Float(), 'g', -1, 32), true
+	case reflect.Float64:
+		return strconv.AppendFloat(buf, rv.Float(), 'g', -1, 64), true
+	case reflect.Bool:
+		return strconv.AppendBool(buf, rv.Bool()), true
+	case reflect.String:
+		s := rv.String()
+		return append(buf, s...), true
+	}
+	return
+}
+
+var valuerReflectType = reflect.TypeOf((*driver.Valuer)(nil)).Elem()
+
+// callValuerValue returns vr.Value(), with one exception:
+// If vr.Value is an auto-generated method on a pointer type and the
+// pointer is nil, it would panic at runtime in the panicwrap
+// method. Treat it like nil instead.
+// Issue 8415.
+//
+// This is so people can implement driver.Value on value types and
+// still use nil pointers to those types to mean nil/NULL, just like
+// string/*string.
+//
+// This function is mirrored in the database/sql/driver package.
+func callValuerValue(vr driver.Valuer) (v driver.Value, err error) {
+	if rv := reflect.ValueOf(vr); rv.Kind() == reflect.Ptr &&
+		rv.IsNil() &&
+		rv.Type().Elem().Implements(valuerReflectType) {
+		return nil, nil
+	}
+	return vr.Value()
+}
+
+// decimal composes or decomposes a decimal value to and from individual parts.
+// There are four parts: a boolean negative flag, a form byte with three possible states
+// (finite=0, infinite=1, NaN=2), a base-2 big-endian integer
+// coefficient (also known as a significand) as a []byte, and an int32 exponent.
+// These are composed into a final value as "decimal = (neg) (form=finite) coefficient * 10 ^ exponent".
+// A zero length coefficient is a zero value.
+// The big-endian integer coefficient stores the most significant byte first (at coefficient[0]).
+// If the form is not finite the coefficient and exponent should be ignored.
+// The negative parameter may be set to true for any form, although implementations are not required
+// to respect the negative parameter in the non-finite form.
+//
+// Implementations may choose to set the negative parameter to true on a zero or NaN value,
+// but implementations that do not differentiate between negative and positive
+// zero or NaN values should ignore the negative parameter without error.
+// If an implementation does not support Infinity it may be converted into a NaN without error.
+// If a value is set that is larger than what is supported by an implementation,
+// an error must be returned.
+// Implementations must return an error if a NaN or Infinity is attempted to be set while neither
+// are supported.
+//
+// NOTE(kardianos): This is an experimental interface. See https://golang.org/issue/30870
+type decimal interface {
+	decimalDecompose
+	decimalCompose
+}
+
+type decimalDecompose interface {
+	// Decompose returns the internal decimal state in parts.
+	// If the provided buf has sufficient capacity, buf may be returned as the coefficient with
+	// the value set and length set as appropriate.
+	Decompose(buf []byte) (form byte, negative bool, coefficient []byte, exponent int32)
+}
+
+type decimalCompose interface {
+	// Compose sets the internal decimal value from parts. If the value cannot be
+	// represented then an error should be returned.
+	Compose(form byte, negative bool, coefficient []byte, exponent int32) error
+}