gtsocial-umbx

init.go (15599B)

---

 // Copyright 2020 The CCGO Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 package ccgo // import "modernc.org/ccgo/v3/lib"
 
 import (
 	"fmt"
 	"sort"
 	"strings"
 
 	"modernc.org/cc/v3"
 )
 
 func isAggregateTypeOrUnion(t cc.Type) bool {
 	switch t.Kind() {
 	case cc.Struct, cc.Union, cc.Array:
 		return true
 	}
 
 	return false
 }
 
 // 6.7.8 Initialization
 func (p *project) initializer(f *function, n *cc.Initializer, t cc.Type, sc cc.StorageClass, tld *tld) {
 	lm := map[*cc.Initializer][]cc.StringID{}
 	tm := map[*cc.Initializer][]cc.StringID{}
 	s := p.initializerFlatten(n, lm, tm)
 	sort.Slice(s, func(i, j int) bool {
 		a := s[i]
 		b := s[j]
 		if a.Offset < b.Offset {
 			return true
 		}
 
 		if a.Offset > b.Offset {
 			return false
 		}
 
 		if a.Field == nil || b.Field == nil || !a.Field.IsBitField() || !b.Field.IsBitField() {
 			panic(todo("%v: internal error: off %#x, %v: off %#x, t %v", a.Position(), a.Offset, b.Position(), b.Offset, t))
 		}
 
 		return a.Field.BitFieldOffset() < b.Field.BitFieldOffset()
 	})
 	p.initializerInner("", 0, f, s, t, sc, tld, nil, lm, tm)
 }
 
 func (p *project) initializerInner(tag string, off uintptr, f *function, s []*cc.Initializer, t cc.Type, sc cc.StorageClass, tld *tld, patchField cc.Field, lm, tm map[*cc.Initializer][]cc.StringID) {
 	// 11: The initializer for a scalar shall be a single expression, optionally
 	// enclosed in braces. The initial value of the object is that of the
 	// expression (after conversion); the same type constraints and conversions as
 	// for simple assignment apply, taking the type of the scalar to be the
 	// unqualified version of its declared type.
 	if t.IsScalarType() && len(s) == 1 {
 		p.w("%s%s", tidyComment("", s[0]), tag)
 		switch {
 		case tld != nil && t.Kind() == cc.Ptr && s[0].AssignmentExpression.Operand.Value() == nil:
 			tld.patches = append(tld.patches, initPatch{t, s[0], patchField})
 			p.w(" 0 ")
 		default:
 			p.assignmentExpression(f, s[0].AssignmentExpression, t, exprValue, 0)
 		}
 		return
 	}
 
 	// 12: The rest of this subclause deals with initializers for objects that have
 	// aggregate or union type.
 
 	k := t.Kind()
 
 	// 13: The initializer for a structure or union object that has automatic
 	// storage duration shall be either an initializer list as described below, or
 	// a single expression that has compatible structure or union type. In the
 	// latter case, the initial value of the object, including unnamed members, is
 	// that of the expression.
 	if sc == cc.Automatic && len(s) == 1 {
 		switch k {
 		case cc.Struct, cc.Union:
 			if compatibleStructOrUnion(t, s[0].AssignmentExpression.Operand.Type()) {
 				p.w("%s%s", tidyComment("", s[0]), tag)
 				p.assignmentExpression(f, s[0].AssignmentExpression, t, exprValue, 0)
 				return
 			}
 		}
 	}
 
 	if k == cc.Array && len(s) == 1 {
 		et := t.Elem()
 		switch {
 		case isCharType(et):
 			// 14: An array of character type may be initialized by a character string
 			// literal, optionally enclosed in braces. Successive characters of the
 			// character string literal (including the terminating null character if there
 			// is room or if the array is of unknown size) initialize the elements of the
 			// array.
 			if x, ok := s[0].AssignmentExpression.Operand.Value().(cc.StringValue); ok {
 				p.w("%s%s", tidyComment("", s[0]), tag)
 				str := cc.StringID(x).String()
 				slen := uintptr(len(str)) + 1
 				alen := t.Len()
 				switch {
 				case alen < slen-1:
 					p.w("*(*%s)(unsafe.Pointer(%s))", p.typ(s[0], t), p.stringLiteralString(str[:alen]))
 				case alen < slen:
 					p.w("*(*%s)(unsafe.Pointer(%s))", p.typ(s[0], t), p.stringLiteralString(str))
 				default: // alen >= slen
 					p.w("*(*%s)(unsafe.Pointer(%s))", p.typ(s[0], t), p.stringLiteralString(str+strings.Repeat("\x00", int(alen-slen))))
 				}
 				return
 			}
 		case p.isWCharType(et):
 			// 15: An array with element type compatible with wchar_t may be initialized by
 			// a wide string literal, optionally enclosed in braces. Successive wide
 			// characters of the wide string literal (including the terminating null wide
 			// character if there is room or if the array is of unknown size) initialize
 			// the elements of the array.
 			if x, ok := s[0].AssignmentExpression.Operand.Value().(cc.WideStringValue); ok {
 				p.w("%s%s", tidyComment("", s[0]), tag)
 				str := []rune(cc.StringID(x).String())
 				slen := uintptr(len(str)) + 1
 				alen := t.Len()
 				switch {
 				case alen < slen-1:
 					panic(todo("", p.pos(s[0])))
 				case alen < slen:
 					p.w("*(*%s)(unsafe.Pointer(%s))", p.typ(s[0], t), p.wideStringLiteral(x, 0))
 				default: // alen >= slen
 					p.w("*(*%s)(unsafe.Pointer(%s))", p.typ(s[0], t), p.wideStringLiteral(x, int(alen-slen)))
 				}
 				return
 			}
 		}
 	}
 
 	// 16: Otherwise, the initializer for an object that has aggregate or union
 	// type shall be a brace-enclosed list of initializers for the elements or
 	// named members.
 	switch k {
 	case cc.Array:
 		p.initializerArray(tag, off, f, s, t, sc, tld, lm, tm)
 	case cc.Struct:
 		p.initializerStruct(tag, off, f, s, t, sc, tld, lm, tm)
 	case cc.Union:
 		p.initializerUnion(tag, off, f, s, t, sc, tld, lm, tm)
 	default:
 		panic(todo("%v: internal error: %v alias %v %v", s[0].Position(), t, t.Alias(), len(s)))
 	}
 }
 
 func (p *project) initializerArray(tag string, off uintptr, f *function, s []*cc.Initializer, t cc.Type, sc cc.StorageClass, tld *tld, lm, tm map[*cc.Initializer][]cc.StringID) {
 	if len(s) == 0 {
 		p.w("%s%s{}", tag, p.typ(nil, t))
 		return
 	}
 
 	et := t.Elem()
 	esz := et.Size()
 	s0 := s[0]
 	p.w("%s%s%s{", initComment(s0, lm), tag, p.typ(s0, t))
 	var a [][]*cc.Initializer
 	for len(s) != 0 {
 		s2, parts, _ := p.initializerArrayElement(off, s, esz)
 		s = s2
 		a = append(a, parts)
 	}
 	mustIndex := uintptr(len(a)) != t.Len()
 	var parts []*cc.Initializer
 	for _, parts = range a {
 		var comma *cc.Token
 		comma = parts[len(parts)-1].TrailingComma()
 		elemOff := (parts[0].Offset - off) / esz * esz
 		tag = ""
 		if mustIndex {
 			tag = fmt.Sprintf("%d:", elemOff/esz)
 		}
 		p.initializerInner(tag, off+elemOff, f, parts, et, sc, tld, nil, lm, tm)
 		p.preCommaSep(comma)
 		p.w(",")
 	}
 	p.w("%s}", initComment(parts[len(parts)-1], tm))
 }
 
 func initComment(n *cc.Initializer, m map[*cc.Initializer][]cc.StringID) string {
 	a := m[n]
 	if len(a) == 0 {
 		return ""
 	}
 
 	m[n] = a[1:]
 	return tidyCommentString(a[0].String())
 }
 
 func (p *project) initializerArrayElement(off uintptr, s []*cc.Initializer, elemSize uintptr) (r []*cc.Initializer, parts []*cc.Initializer, isZero bool) {
 	r = s
 	isZero = true
 	valueOff := s[0].Offset - off
 	elemOff := valueOff - valueOff%elemSize
 	nextOff := elemOff + elemSize
 	for len(s) != 0 {
 		if v := s[0]; v.Offset-off < nextOff {
 			s = s[1:]
 			parts = append(parts, v)
 			if !v.AssignmentExpression.Operand.IsZero() {
 				isZero = false
 			}
 			continue
 		}
 
 		break
 	}
 	return r[len(parts):], parts, isZero
 }
 
 func (p *project) initializerStruct(tag string, off uintptr, f *function, s []*cc.Initializer, t cc.Type, sc cc.StorageClass, tld *tld, lm, tm map[*cc.Initializer][]cc.StringID) {
 	if len(s) == 0 {
 		p.w("%s%s{}", tag, p.typ(nil, t))
 		return
 	}
 
 	if t.HasFlexibleMember() {
 		p.err(s[0], "flexible array members not supported")
 		return
 	}
 
 	p.w("%s%s%s{", initComment(s[0], lm), tag, p.typ(s[0], t))
 	var parts []*cc.Initializer
 	var isZero bool
 	var fld cc.Field
 	for len(s) != 0 {
 		var comma *cc.Token
 		s, fld, parts, isZero = p.structInitializerParts(off, s, t)
 		if isZero {
 			continue
 		}
 
 		if fld.Type().IsIncomplete() {
 			panic(todo(""))
 		}
 
 		comma = parts[len(parts)-1].TrailingComma()
 		tag = fmt.Sprintf("%s:", p.fieldName2(parts[0], fld))
 		ft := fld.Type()
 		switch {
 		case fld.IsBitField():
 			bft := p.bitFileType(parts[0], fld.BitFieldBlockWidth())
 			off0 := fld.Offset()
 			first := true
 			for _, v := range parts {
 				if v.AssignmentExpression.Operand.IsZero() {
 					continue
 				}
 
 				if !first {
 					p.w("|")
 				}
 				first = false
 				bitFld := v.Field
 				p.w("%s%s", tidyComment("", v.AssignmentExpression), tag)
 				tag = ""
 				p.assignmentExpression(f, v.AssignmentExpression, bft, exprValue, 0)
 				p.w("&%#x", uint64(1)<<uint64(bitFld.BitFieldWidth())-1)
 				if o := bitFld.BitFieldOffset() + 8*int((bitFld.Offset()-off0)); o != 0 {
 					p.w("<<%d", o)
 				}
 			}
 		default:
 			p.initializerInner(tag, off+fld.Offset(), f, parts, ft, sc, tld, fld, lm, tm)
 		}
 		p.preCommaSep(comma)
 		p.w(",")
 	}
 	p.w("%s}", initComment(parts[len(parts)-1], tm))
 }
 
 func (p *project) preCommaSep(comma *cc.Token) {
 	if comma == nil {
 		return
 	}
 
 	p.w("%s", strings.TrimSpace(comma.Sep.String()))
 }
 
 func (p *project) structInitializerParts(off uintptr, s []*cc.Initializer, t cc.Type) (r []*cc.Initializer, fld cc.Field, parts []*cc.Initializer, isZero bool) {
 	if len(s) == 0 {
 		return nil, nil, nil, true
 	}
 
 	part := s[0]
 	isZero = part.AssignmentExpression.Operand.IsZero()
 	parts = append(parts, part)
 	s = s[1:]
 	fld, _, fNext := p.containingStructField(part, off, t)
 	for len(s) != 0 {
 		part = s[0]
 		vOff := part.Offset
 		if vOff >= fNext {
 			break
 		}
 
 		isZero = isZero && part.AssignmentExpression.Operand.IsZero()
 		parts = append(parts, part)
 		s = s[1:]
 	}
 	return s, fld, parts, isZero
 }
 
 func (p *project) containingStructField(part *cc.Initializer, off uintptr, t cc.Type) (f cc.Field, fOff, fNext uintptr) {
 	nf := t.NumField()
 	vOff := part.Offset
 	for i := []int{0}; i[0] < nf; i[0]++ {
 		f = t.FieldByIndex(i)
 		if f.IsBitField() && f.Name() == 0 { // Anonymous bit fields cannot be initialized.
 			continue
 		}
 
 		fOff = off + f.Offset()
 		switch {
 		case f.IsBitField():
 			fNext = fOff + uintptr(f.BitFieldBlockWidth())>>3
 		default:
 			fNext = fOff + f.Type().Size()
 		}
 		if vOff >= fOff && vOff < fNext {
 			return f, fOff, fNext
 		}
 	}
 
 	panic(todo("%v: internal error", p.pos(part)))
 }
 
 func (p *project) initializerUnion(tag string, off uintptr, f *function, s []*cc.Initializer, t cc.Type, sc cc.StorageClass, tld *tld, lm, tm map[*cc.Initializer][]cc.StringID) {
 	if len(s) == 0 {
 		p.w("%s%s{}", tag, p.typ(nil, t))
 		return
 	}
 
 	if t.HasFlexibleMember() {
 		p.err(s[0], "flexible array members not supported")
 		return
 	}
 
 	parts, isZero := p.initializerUnionField(off, s, t)
 	if len(parts) == 0 || isZero {
 		p.w("%s%s%s{", initComment(s[0], lm), tag, p.typ(s[0], t))
 		p.w("%s}", initComment(parts[len(parts)-1], tm))
 		return
 	}
 
 	p.w("%sfunc() (r %s) {", tag, p.typ(parts[0], t))
 	for _, part := range parts {
 		var ft cc.Type
 		fld := part.Field
 		if fld != nil && fld.IsBitField() {
 		}
 
 		if ft == nil {
 			ft = part.Type()
 		}
 		if ft.Kind() == cc.Array {
 			et := ft.Elem()
 			switch {
 			case isCharType(et):
 				switch x := part.AssignmentExpression.Operand.Value().(type) {
 				case cc.StringValue:
 					str := cc.StringID(x).String()
 					slen := uintptr(len(str)) + 1
 					alen := ft.Len()
 					switch {
 					case alen < slen-1:
 						p.w("copy(((*[%d]byte)(unsafe.Pointer(uintptr(unsafe.Pointer(&r))+%d)))[:], (*[%d]byte)(unsafe.Pointer(%s))[:])\n", alen, part.Offset-off, alen, p.stringLiteralString(str[:alen]))
 					case alen < slen:
 						p.w("copy(((*[%d]byte)(unsafe.Pointer(uintptr(unsafe.Pointer(&r))+%d)))[:], (*[%d]byte)(unsafe.Pointer(%s))[:])\n", alen, part.Offset-off, alen, p.stringLiteralString(str))
 					default: // alen >= slen
 						p.w("copy(((*[%d]byte)(unsafe.Pointer(uintptr(unsafe.Pointer(&r))+%d)))[:], (*[%d]byte)(unsafe.Pointer(%s))[:])\n", alen, part.Offset-off, alen, p.stringLiteralString(str+strings.Repeat("\x00", int(alen-slen))))
 					}
 					continue
 				default:
 					panic(todo("%v: %v <- %T", p.pos(part), et, x))
 				}
 			case p.isWCharType(et):
 				panic(todo(""))
 			}
 			ft = et
 		}
 		switch {
 		case fld != nil && fld.IsBitField():
 			bft := p.bitFileType(part, fld.BitFieldBlockWidth())
 			p.w("*(*%s)(unsafe.Pointer(uintptr(unsafe.Pointer(&r))+%d)) |= ", p.typ(part, bft), part.Offset-off)
 			p.assignmentExpression(f, part.AssignmentExpression, bft, exprValue, 0)
 			p.w("&%#x", uint64(1)<<uint64(fld.BitFieldWidth())-1)
 			if o := fld.BitFieldOffset(); o != 0 {
 				p.w("<<%d", o)
 			}
 		default:
 			p.w("*(*%s)(unsafe.Pointer(uintptr(unsafe.Pointer(&r))+%d)) = ", p.typ(part, ft), part.Offset-off)
 			p.assignmentExpression(f, part.AssignmentExpression, ft, exprValue, 0)
 		}
 		p.w("\n")
 	}
 	p.w("return r\n")
 	p.w("}()")
 }
 
 func (p *project) initializerUnionField(off uintptr, s []*cc.Initializer, t cc.Type) (parts []*cc.Initializer, isZero bool) {
 	isZero = true
 	nextOff := off + t.Size()
 	for len(s) != 0 {
 		if v := s[0]; v.Offset < nextOff {
 			s = s[1:]
 			parts = append(parts, v)
 			isZero = isZero && v.AssignmentExpression.Operand.IsZero()
 			continue
 		}
 
 		break
 	}
 	return parts, isZero
 }
 
 func compatibleStructOrUnion(t1, t2 cc.Type) bool {
 	switch t1.Kind() {
 	case cc.Struct:
 		if t2.Kind() != cc.Struct {
 			return false
 		}
 	case cc.Union:
 		if t2.Kind() != cc.Union {
 			return false
 		}
 	default:
 		return false
 	}
 
 	if tag := t1.Tag(); tag != 0 && t2.Tag() != tag {
 		return false
 	}
 
 	nf := t1.NumField()
 	if t2.NumField() != nf {
 		return false
 	}
 
 	for i := []int{0}; i[0] < nf; i[0]++ {
 		f1 := t1.FieldByIndex(i)
 		f2 := t2.FieldByIndex(i)
 		nm := f1.Name()
 		if f2.Name() != nm {
 			return false
 		}
 
 		ft1 := f1.Type()
 		ft2 := f2.Type()
 		if ft1.Size() != ft2.Size() ||
 			f1.IsBitField() != f2.IsBitField() ||
 			f1.BitFieldOffset() != f2.BitFieldOffset() ||
 			f1.BitFieldWidth() != f2.BitFieldWidth() {
 			return false
 		}
 
 		if !compatibleType(ft1, ft2) {
 			return false
 		}
 	}
 	return true
 }
 
 func compatibleType(t1, t2 cc.Type) bool {
 	if t1.Kind() != t2.Kind() {
 		return false
 	}
 
 	switch t1.Kind() {
 	case cc.Array:
 		if t1.Len() != t2.Len() || !compatibleType(t1.Elem(), t2.Elem()) {
 			return false
 		}
 	case cc.Struct, cc.Union:
 		if !compatibleStructOrUnion(t1, t2) {
 			return false
 		}
 	}
 	return true
 }
 
 func (p *project) bitFileType(n cc.Node, bits int) cc.Type {
 	switch bits {
 	case 8:
 		return p.task.cfg.ABI.Type(cc.UChar)
 	case 16:
 		return p.task.cfg.ABI.Type(cc.UShort)
 	case 32:
 		return p.task.cfg.ABI.Type(cc.UInt)
 	case 64:
 		return p.task.cfg.ABI.Type(cc.ULongLong)
 	default:
 		panic(todo("%v: internal error: %v", n.Position(), bits))
 	}
 }
 
 func (p *project) isWCharType(t cc.Type) bool {
 	if t.IsAliasType() {
 		if id := t.AliasDeclarator().Name(); id == idWcharT ||
 			p.task.goos == "windows" && id == idWinWchar {
 			return true
 		}
 	}
 
 	return false
 }
 
 func isCharType(t cc.Type) bool {
 	switch t.Kind() {
 	case cc.Char, cc.SChar, cc.UChar:
 		return true
 	}
 
 	return false
 }
 
 func (p *project) initializerFlatten(n *cc.Initializer, lm, tm map[*cc.Initializer][]cc.StringID) (s []*cc.Initializer) {
 	switch n.Case {
 	case cc.InitializerExpr: // AssignmentExpression
 		return append(s, n)
 	case cc.InitializerInitList: // '{' InitializerList ',' '}'
 		first := true
 		for list := n.InitializerList; list != nil; list = list.InitializerList {
 			in := list.Initializer
 			k := in
 			if in.Case != cc.InitializerExpr {
 				k = nil
 			}
 			if first {
 				lm[k] = append(lm[k], append(lm[nil], n.Token.Sep)...)
 				if k != nil {
 					delete(lm, nil)
 				}
 				first = false
 			}
 			if list.InitializerList == nil {
 				tm[k] = append([]cc.StringID{n.Token3.Sep}, append(tm[nil], tm[k]...)...)
 				tm[k] = append(tm[k], append(tm[nil], n.Token3.Sep)...)
 				if k != nil {
 					delete(tm, nil)
 				}
 			}
 			s = append(s, p.initializerFlatten(in, lm, tm)...)
 		}
 		return s
 	default:
 		panic(todo("%v: internal error: %v", n.Position(), n.Case))
 	}
 }