miqt/cmd/genbindings/emitgo.go

1112 lines
36 KiB
Go

package main
import (
"C"
"fmt"
"go/format"
"log"
"path"
"sort"
"strings"
)
func goReservedWord(s string) bool {
switch s {
case "default", "const", "func", "var", "type", "len", "new", "copy", "import", "range", "string", "map", "int", "select",
"super", "ret": // not language-reserved words, but a binding-reserved words
return true
default:
return false
}
}
func (p CppParameter) RenderTypeGo(gfs *goFileState) string {
if p.Pointer && p.ParameterType == "char" {
return "string"
}
if p.ParameterType == "QString" {
return "string"
}
if p.ParameterType == "QByteArray" {
return "[]byte"
}
if t, ok := p.QListOf(); ok {
return "[]" + t.RenderTypeGo(gfs)
}
if t, ok := p.QSetOf(); ok {
return "map[" + t.RenderTypeGo(gfs) + "]struct{}"
}
if t1, t2, ok := p.QMapOf(); ok {
return "map[" + t1.RenderTypeGo(gfs) + "]" + t2.RenderTypeGo(gfs)
}
if t1, t2, ok := p.QPairOf(); ok {
// Design QPair using capital-named members, in case it gets passed
// across packages
return "struct { First " + t1.RenderTypeGo(gfs) + " ; Second " + t2.RenderTypeGo(gfs) + " }"
}
if p.ParameterType == "void" && p.Pointer {
return "unsafe.Pointer"
}
ret := ""
switch p.ParameterType {
case "unsigned char", "uchar", "quint8":
// Go byte is unsigned
ret += "byte"
case "char", "qint8", "signed char":
ret += "int8" // Signed
case "short", "qint16", "int16_t":
ret += "int16"
case "ushort", "quint16", "unsigned short", "uint16_t":
ret += "uint16"
case "long":
// Windows ILP32 - 32-bits
// Linux LP64 - 64-bits
if C.sizeof_long == 4 {
ret += "int32"
} else {
ret += "int64"
}
case "ulong", "unsigned long":
if C.sizeof_long == 4 {
ret += "uint32"
} else {
ret += "uint64"
}
case "unsigned int":
ret += "uint"
case "qint32":
ret += "int32"
case "quint32":
ret += "uint32"
case "qlonglong", "qint64", "long long":
ret += "int64"
case "qulonglong", "quint64", "unsigned long long":
ret += "uint64"
case "float":
ret += "float32"
case "double", "qreal":
ret += "float64"
case "size_t": // size_t is unsigned
if C.sizeof_size_t == 4 {
ret += "uint32"
} else {
ret += "uint64"
}
case "qsizetype", "QIntegerForSizeof<std::size_t>::Signed", "qptrdiff", "ptrdiff_t": // all signed
if C.sizeof_size_t == 4 {
ret += "int32"
} else {
ret += "int64"
}
case "qintptr", "uintptr_t", "intptr_t", "quintptr", "QIntegerForSizeof<void *>::Unsigned", "QIntegerForSizeof<void *>::Signed":
ret += "uintptr"
default:
if ft, ok := p.QFlagsOf(); ok {
if enumInfo, ok := KnownEnums[ft.ParameterType]; ok && enumInfo.PackageName != gfs.currentPackageName {
// Cross-package
ret += path.Base(enumInfo.PackageName) + "." + cabiClassName(ft.ParameterType)
gfs.imports[importPathForQtPackage(enumInfo.PackageName)] = struct{}{}
} else {
// Same package
ret += cabiClassName(ft.ParameterType)
}
} else if enumInfo, ok := KnownEnums[p.ParameterType]; ok {
if enumInfo.PackageName != gfs.currentPackageName {
// Cross-package
ret += path.Base(enumInfo.PackageName) + "." + cabiClassName(p.ParameterType)
gfs.imports[importPathForQtPackage(enumInfo.PackageName)] = struct{}{}
} else {
// Same package
ret += cabiClassName(p.ParameterType)
}
} else if strings.Contains(p.ParameterType, `::`) {
// Inner class
ret += cabiClassName(p.ParameterType)
} else {
// Do not transform this type
ret += p.ParameterType
}
}
if pkg, ok := KnownClassnames[p.ParameterType]; ok && pkg.PackageName != gfs.currentPackageName {
ret = path.Base(pkg.PackageName) + "." + ret
gfs.imports[importPathForQtPackage(pkg.PackageName)] = struct{}{}
}
if p.ByRef || p.Pointer {
ret = "*" + ret
}
return ret // ignore const
}
func (p CppParameter) renderReturnTypeGo(gfs *goFileState) string {
ret := p.RenderTypeGo(gfs)
if ret == "void" {
ret = ""
}
if p.QtClassType() && p.ParameterType != "QString" && p.ParameterType != "QByteArray" && !(p.Pointer || p.ByRef) {
// FIXME normalize this part
ret = "*" + ret
}
return ret
}
func (p CppParameter) parameterTypeCgo() string {
if p.ParameterType == "QString" {
return "C.struct_miqt_string"
}
if p.ParameterType == "QByteArray" {
return "C.struct_miqt_string"
}
if _, ok := p.QListOf(); ok {
return "C.struct_miqt_array"
}
if _, ok := p.QSetOf(); ok {
return "C.struct_miqt_array"
}
if _, _, ok := p.QMapOf(); ok {
return "C.struct_miqt_map"
}
if _, _, ok := p.QPairOf(); ok {
return "C.struct_miqt_map"
}
// Cgo internally binds void* as unsafe.Pointer{}
if p.ParameterType == "void" && p.Pointer {
return "unsafe.Pointer"
}
tmp := strings.Replace(p.RenderTypeCabi(), `*`, "", -1)
if strings.HasPrefix(tmp, "const ") && tmp != "const char" { // Special typedef to make this work for const char* signal parameters
tmp = tmp[6:] // Constness doesn't survive the CABI boundary
}
if strings.HasPrefix(tmp, "unsigned ") {
tmp = "u" + tmp[9:] // Cgo uses uchar, uint instead of full name
}
if strings.HasPrefix(tmp, "signed ") {
tmp = "s" + tmp[7:] // Cgo uses schar
}
tmp = strings.Replace(tmp, `long long`, `longlong`, -1)
tmp = "C." + strings.Replace(tmp, " ", "_", -1)
if p.QtClassType() || p.Pointer || p.ByRef {
return "*" + tmp
} else {
return tmp
}
}
func (p CppParameter) mallocSizeCgoExpression() string {
if p.ParameterType == "QString" || p.ParameterType == "QByteArray" {
return "int(unsafe.Sizeof(C.struct_miqt_string{}))"
}
// Default (sizeof pointer)
return "8"
}
func (gfs *goFileState) emitParametersGo(params []CppParameter) string {
tmp := make([]string, 0, len(params))
skipNext := false
for i, p := range params {
if IsArgcArgv(params, i) {
skipNext = true
tmp = append(tmp, "args []string")
} else if skipNext {
// Skip this parameter, already handled
skipNext = false
} else {
// Ordinary parameter
tmp = append(tmp, p.ParameterName+" "+p.RenderTypeGo(gfs))
}
}
return strings.Join(tmp, ", ")
}
type goFileState struct {
imports map[string]struct{}
currentPackageName string
}
func (gfs *goFileState) emitParametersGo2CABIForwarding(m CppMethod) (preamble string, forwarding string) {
tmp := make([]string, 0, len(m.Parameters)+2)
if !m.IsStatic {
tmp = append(tmp, "this.h")
}
skipNext := false
for i, p := range m.Parameters {
if IsArgcArgv(m.Parameters, i) {
skipNext = true
// QApplication constructor. Convert 'args' into Qt's wanted types
// Qt has a warning in the docs saying these pointers must be valid
// for the entire lifetype of QApplication, so, malloc + never free
// This transformation only affects the Go side. The CABI side is
// projected naturally
preamble += "// Convert []string to long-lived int& argc, char** argv, never call free()\n"
preamble += "argc := (*C.int)(C.malloc(8))\n"
preamble += "*argc = C.int(len(args))\n"
preamble += "argv := (*[0xffff]*C.char)(C.malloc(C.size_t(8 * len(args))))\n"
preamble += "for i := range args {\n"
preamble += "argv[i] = C.CString(args[i])\n"
preamble += "}\n"
tmp = append(tmp, "argc, &argv[0]")
// Additional quirk for QApplication constructor: bind to OS thread
gfs.imports["runtime"] = struct{}{}
preamble += "\n"
preamble += "runtime.LockOSThread() // Prevent Go from migrating the main Qt thread\n"
preamble += "\n"
} else if skipNext {
// Skip this parameter, already handled
skipNext = false
} else {
addPreamble, rvalue := gfs.emitParameterGo2CABIForwarding(p)
preamble += addPreamble
tmp = append(tmp, rvalue)
}
}
return preamble, strings.Join(tmp, ", ")
}
func (gfs *goFileState) emitParameterGo2CABIForwarding(p CppParameter) (preamble string, rvalue string) {
nameprefix := makeNamePrefix(p.ParameterName)
if p.ParameterType == "QString" {
// Go: convert string -> miqt_string*
// CABI: convert miqt_string* -> real QString
gfs.imports["unsafe"] = struct{}{}
preamble += nameprefix + "_ms := C.struct_miqt_string{}\n"
preamble += nameprefix + "_ms.data = C.CString(" + p.ParameterName + ")\n"
preamble += nameprefix + "_ms.len = C.size_t(len(" + p.ParameterName + "))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_ms.data))\n"
rvalue = nameprefix + "_ms"
} else if p.ParameterType == "QByteArray" {
// Go: convert []byte -> miqt_string
// CABI: convert miqt_string -> QByteArray
// n.b. This can ALIAS the existing []byte data
gfs.imports["unsafe"] = struct{}{}
preamble += nameprefix + "_alias := C.struct_miqt_string{}\n"
preamble += nameprefix + "_alias.data = (*C.char)(unsafe.Pointer(&" + p.ParameterName + "[0]))\n"
preamble += nameprefix + "_alias.len = C.size_t(len(" + p.ParameterName + "))\n"
rvalue = nameprefix + "_alias"
} else if listType, ok := p.QListOf(); ok {
// QList<T>
// Go: convert T[] -> t* and len
// CABI: create a real QList<>
gfs.imports["unsafe"] = struct{}{}
mallocSize := listType.mallocSizeCgoExpression()
preamble += nameprefix + "_CArray := (*[0xffff]" + listType.parameterTypeCgo() + ")(C.malloc(C.size_t(" + mallocSize + " * len(" + p.ParameterName + "))))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_CArray))\n"
preamble += "for i := range " + p.ParameterName + "{\n"
listType.ParameterName = p.ParameterName + "[i]"
addPreamble, innerRvalue := gfs.emitParameterGo2CABIForwarding(listType)
preamble += addPreamble
preamble += nameprefix + "_CArray[i] = " + innerRvalue + "\n"
preamble += "}\n"
preamble += nameprefix + "_ma := C.struct_miqt_array{len: C.size_t(len(" + p.ParameterName + ")), data: unsafe.Pointer(" + nameprefix + "_CArray)}\n"
rvalue = nameprefix + "_ma"
} else if _, ok := p.QSetOf(); ok {
panic("QSet<> arguments are not yet implemented") // n.b. doesn't seem to exist in QtCore/QtGui/QtWidgets at all
} else if kType, vType, ok := p.QMapOf(); ok {
// QMap<T>
gfs.imports["unsafe"] = struct{}{}
preamble += nameprefix + "_Keys_CArray := (*[0xffff]" + kType.parameterTypeCgo() + ")(C.malloc(C.size_t(" + kType.mallocSizeCgoExpression() + " * len(" + p.ParameterName + "))))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_Keys_CArray))\n"
preamble += nameprefix + "_Values_CArray := (*[0xffff]" + vType.parameterTypeCgo() + ")(C.malloc(C.size_t(" + vType.mallocSizeCgoExpression() + " * len(" + p.ParameterName + "))))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_Values_CArray))\n"
preamble += nameprefix + "_ctr := 0\n"
preamble += "for " + nameprefix + "_k, " + nameprefix + "_v := range " + p.ParameterName + "{\n"
kType.ParameterName = nameprefix + "_k"
addPreamble, innerRvalue := gfs.emitParameterGo2CABIForwarding(kType)
preamble += addPreamble
preamble += nameprefix + "_Keys_CArray[" + nameprefix + "_ctr] = " + innerRvalue + "\n"
vType.ParameterName = nameprefix + "_v"
addPreamble, innerRvalue = gfs.emitParameterGo2CABIForwarding(vType)
preamble += addPreamble
preamble += nameprefix + "_Values_CArray[" + nameprefix + "_ctr] = " + innerRvalue + "\n"
preamble += nameprefix + "_ctr++\n"
preamble += "}\n"
preamble += nameprefix + "_mm := C.struct_miqt_map{\nlen: C.size_t(len(" + p.ParameterName + ")),\nkeys: unsafe.Pointer(" + nameprefix + "_Keys_CArray),\nvalues: unsafe.Pointer(" + nameprefix + "_Values_CArray),\n}\n"
rvalue = nameprefix + "_mm"
} else if kType, vType, ok := p.QPairOf(); ok {
// QPair<T>
gfs.imports["unsafe"] = struct{}{}
preamble += nameprefix + "_First_CArray := (*[0xffff]" + kType.parameterTypeCgo() + ")(C.malloc(C.size_t(" + kType.mallocSizeCgoExpression() + ")))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_First_CArray))\n"
preamble += nameprefix + "_Second_CArray := (*[0xffff]" + vType.parameterTypeCgo() + ")(C.malloc(C.size_t(" + vType.mallocSizeCgoExpression() + ")))\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_Second_CArray))\n"
kType.ParameterName = p.ParameterName + ".First"
addPreamble, innerRvalue := gfs.emitParameterGo2CABIForwarding(kType)
preamble += addPreamble
preamble += nameprefix + "_First_CArray[0] = " + innerRvalue + "\n"
vType.ParameterName = p.ParameterName + ".Second"
addPreamble, innerRvalue = gfs.emitParameterGo2CABIForwarding(vType)
preamble += addPreamble
preamble += nameprefix + "_Second_CArray[0] = " + innerRvalue + "\n"
preamble += nameprefix + "_pair := C.struct_miqt_map{\nlen: 1,\nkeys: unsafe.Pointer(" + nameprefix + "_First_CArray),\nvalues: unsafe.Pointer(" + nameprefix + "_Second_CArray),\n}\n"
rvalue = nameprefix + "_pair"
} else if p.Pointer && p.ParameterType == "char" {
// Single char* argument
gfs.imports["unsafe"] = struct{}{}
preamble += nameprefix + "_Cstring := C.CString(" + p.ParameterName + ")\n"
preamble += "defer C.free(unsafe.Pointer(" + nameprefix + "_Cstring))\n"
rvalue = nameprefix + "_Cstring"
} else if /*(p.Pointer || p.ByRef) &&*/ p.QtClassType() {
// The C++ type is a pointer to Qt class
// We want our functions to accept the Go wrapper type, and forward as cPointer()
// cPointer() returns the cgo pointer which only works in the same package -
// anything cross-package needs to go via unsafe.Pointer
if classInfo, ok := KnownClassnames[p.ParameterType]; ok && gfs.currentPackageName != classInfo.PackageName {
// Cross-package
rvalue = "(" + p.parameterTypeCgo() + ")(" + p.ParameterName + ".UnsafePointer())"
} else {
// Same package
rvalue = p.ParameterName + ".cPointer()"
}
} else if p.IntType() || p.IsFlagType() || p.IsKnownEnum() || p.ParameterType == "bool" {
if p.Pointer || p.ByRef {
gfs.imports["unsafe"] = struct{}{}
rvalue = "(" + p.parameterTypeCgo() + ")(unsafe.Pointer(" + p.ParameterName + "))" // n.b. This may not work if the integer type conversion was wrong
} else {
rvalue = "(" + p.parameterTypeCgo() + ")(" + p.ParameterName + ")"
}
} else {
// Default
rvalue = p.ParameterName
}
return preamble, rvalue
}
func (gfs *goFileState) emitCabiToGo(assignExpr string, rt CppParameter, rvalue string) string {
shouldReturn := assignExpr // "return "
afterword := ""
namePrefix := makeNamePrefix(rt.ParameterName)
if rt.Void() {
shouldReturn = ""
return shouldReturn + " " + rvalue + "\n" + afterword
} else if rt.ParameterType == "void" && rt.Pointer {
gfs.imports["unsafe"] = struct{}{}
return assignExpr + " (unsafe.Pointer)(" + rvalue + ")\n"
} else if rt.ParameterType == "char" && rt.Pointer {
// Qt functions normally return QString - anything returning char*
// is something like QByteArray.Data() where it returns an unsafe
// internal pointer
// However in case this is a signal, we need to be able to marshal both
// forwards and backwards with the same types, this has to be a string
// in both cases
// This is not a miqt_string and therefore MIQT did not allocate it,
// and therefore we don't have to free it either
gfs.imports["unsafe"] = struct{}{}
shouldReturn = namePrefix + "_ret := "
afterword += assignExpr + " C.GoString(" + namePrefix + "_ret)\n"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if rt.ParameterType == "QString" {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_ms C.struct_miqt_string = "
afterword += namePrefix + "_ret := C.GoStringN(" + namePrefix + "_ms.data, C.int(int64(" + namePrefix + "_ms.len)))\n"
afterword += "C.free(unsafe.Pointer(" + namePrefix + "_ms.data))\n"
afterword += assignExpr + namePrefix + "_ret"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if rt.ParameterType == "QByteArray" {
// We receive the CABI type of a miqt_string. Convert it into []byte
// We must free the miqt_string data pointer - this is a data copy,
// not an alias
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_bytearray C.struct_miqt_string = "
afterword += namePrefix + "_ret := C.GoBytes(unsafe.Pointer(" + namePrefix + "_bytearray.data), C.int(int64(" + namePrefix + "_bytearray.len)))\n"
afterword += "C.free(unsafe.Pointer(" + namePrefix + "_bytearray.data))\n"
afterword += assignExpr + namePrefix + "_ret"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if t, ok := rt.QListOf(); ok {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_ma C.struct_miqt_array = "
afterword += namePrefix + "_ret := make([]" + t.RenderTypeGo(gfs) + ", int(" + namePrefix + "_ma.len))\n"
afterword += namePrefix + "_outCast := (*[0xffff]" + t.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_ma.data)) // hey ya\n"
afterword += "for i := 0; i < int(" + namePrefix + "_ma.len); i++ {\n"
afterword += gfs.emitCabiToGo(namePrefix+"_ret[i] = ", t, namePrefix+"_outCast[i]")
afterword += "}\n"
afterword += assignExpr + " " + namePrefix + "_ret\n"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if t, ok := rt.QSetOf(); ok {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_ma C.struct_miqt_array = "
afterword += namePrefix + "_ret := make(map[" + t.RenderTypeGo(gfs) + "]struct{}, int(" + namePrefix + "_ma.len))\n"
afterword += namePrefix + "_outCast := (*[0xffff]" + t.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_ma.data)) // hey ya\n"
afterword += "for i := 0; i < int(" + namePrefix + "_ma.len); i++ {\n"
afterword += gfs.emitCabiToGo(namePrefix+"_element := ", t, namePrefix+"_outCast[i]") + "\n"
afterword += namePrefix + "_ret[" + namePrefix + "_element] = struct{}{}\n"
afterword += "}\n"
afterword += assignExpr + " " + namePrefix + "_ret\n"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if kType, vType, ok := rt.QMapOf(); ok {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_mm C.struct_miqt_map = "
afterword += namePrefix + "_ret := make(map[" + kType.RenderTypeGo(gfs) + "]" + vType.RenderTypeGo(gfs) + ", int(" + namePrefix + "_mm.len))\n"
afterword += namePrefix + "_Keys := (*[0xffff]" + kType.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_mm.keys))\n"
afterword += namePrefix + "_Values := (*[0xffff]" + vType.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_mm.values))\n"
afterword += "for i := 0; i < int(" + namePrefix + "_mm.len); i++ {\n"
afterword += gfs.emitCabiToGo(namePrefix+"_entry_Key := ", kType, namePrefix+"_Keys[i]") + "\n"
afterword += gfs.emitCabiToGo(namePrefix+"_entry_Value := ", vType, namePrefix+"_Values[i]") + "\n"
afterword += namePrefix + "_ret[" + namePrefix + "_entry_Key] = " + namePrefix + "_entry_Value\n"
afterword += "}\n"
afterword += assignExpr + " " + namePrefix + "_ret\n"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if kType, vType, ok := rt.QPairOf(); ok {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_mm C.struct_miqt_map = "
afterword += namePrefix + "_First_CArray := (*[0xffff]" + kType.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_mm.keys))\n"
afterword += namePrefix + "_Second_CArray := (*[0xffff]" + vType.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_mm.values))\n"
afterword += gfs.emitCabiToGo(namePrefix+"_entry_First := ", kType, namePrefix+"_First_CArray[0]") + "\n"
afterword += gfs.emitCabiToGo(namePrefix+"_entry_Second := ", vType, namePrefix+"_Second_CArray[0]") + "\n"
afterword += assignExpr + " " + rt.RenderTypeGo(gfs) + " { First: " + namePrefix + "_entry_First , Second: " + namePrefix + "_entry_Second }\n"
return shouldReturn + " " + rvalue + "\n" + afterword
} else if rt.QtClassType() {
// Construct our Go type based on this inner CABI type
shouldReturn = "" + namePrefix + "_ret := "
crossPackage := ""
pkg, ok := KnownClassnames[rt.ParameterType]
if !ok {
panic("emitCabiToGo: Encountered an unknown Qt class")
}
if pkg.PackageName != gfs.currentPackageName {
crossPackage = path.Base(pkg.PackageName) + "."
gfs.imports[importPathForQtPackage(pkg.PackageName)] = struct{}{}
}
// FIXME This needs to somehow figure out the real child pointers
extraConstructArgs := strings.Repeat(", nil", len(pkg.Class.AllInherits()))
if rt.Pointer || rt.ByRef {
gfs.imports["unsafe"] = struct{}{}
return assignExpr + " " + crossPackage + "UnsafeNew" + cabiClassName(rt.ParameterType) + "(unsafe.Pointer(" + rvalue + ")" + extraConstructArgs + ")"
} else {
// This is return by value, but CABI has new'd it into a
// heap type for us
// To preserve Qt's approximate semantics, add a runtime
// finalizer to automatically Delete once the type goes out
// of Go scope
if crossPackage == "" {
afterword += namePrefix + "_goptr := new" + cabiClassName(rt.ParameterType) + "(" + namePrefix + "_ret" + extraConstructArgs + ")\n"
} else {
gfs.imports["unsafe"] = struct{}{}
afterword += namePrefix + "_goptr := " + crossPackage + "UnsafeNew" + cabiClassName(rt.ParameterType) + "(unsafe.Pointer(" + namePrefix + "_ret)" + extraConstructArgs + ")\n"
}
afterword += namePrefix + "_goptr.GoGC() // Qt uses pass-by-value semantics for this type. Mimic with finalizer\n"
// If this is a function return, we have converted value-returned Qt types to pointers
// If this is a slot return, we haven't
// TODO standardize this
if strings.Contains(assignExpr, `return`) {
afterword += assignExpr + "" + namePrefix + "_goptr\n"
} else {
afterword += assignExpr + " *" + namePrefix + "_goptr\n"
}
}
return shouldReturn + " " + rvalue + "\n" + afterword
} else if rt.IntType() || rt.IsKnownEnum() || rt.IsFlagType() || rt.ParameterType == "bool" || rt.QtCppOriginalType != nil {
if rt.Pointer || rt.ByRef {
// Cast must go via unsafe.Pointer
gfs.imports["unsafe"] = struct{}{}
return assignExpr + "(" + rt.RenderTypeGo(gfs) + ")(unsafe.Pointer(" + rvalue + "))\n"
}
// Need to cast Cgo type to Go int type
// Optimize assignment to avoid temporary
return assignExpr + "(" + rt.RenderTypeGo(gfs) + ")(" + rvalue + ")\n"
} else {
panic(fmt.Sprintf("emitgo::emitCabiToGo missing type handler for parameter %+v", rt))
}
}
func emitGo(src *CppParsedHeader, headerName string, packageName string) (string, error) {
ret := strings.Builder{}
ret.WriteString(`package ` + path.Base(packageName) + `
/*
#include "gen_` + headerName + `"
#include <stdlib.h>
*/
import "C"
%%_IMPORTLIBS_%%
`)
gfs := goFileState{
imports: map[string]struct{}{},
currentPackageName: packageName,
}
// Check if short-named enums are allowed.
// We only allow short names if there are no conflicts anywhere in the whole
// file. This doesn't fully defend against cross-file conflicts but those
// should hopefully be rare enough
preventShortNames := map[string]struct{}{}
{
nameTest := map[string]string{}
nextEnum:
for _, e := range src.Enums {
shortEnumName := e.ShortEnumName()
// Disallow entry<-->entry collisions
for _, ee := range e.Entries {
if other, ok := nameTest[shortEnumName+"::"+ee.EntryName]; ok {
preventShortNames[e.EnumName] = struct{}{} // Our full enum name
preventShortNames[other] = struct{}{} // Their full enum name
continue nextEnum
}
nameTest[shortEnumName+"::"+ee.EntryName] = e.EnumName
if _, ok := KnownClassnames[shortEnumName+"::"+ee.EntryName]; ok {
preventShortNames[e.EnumName] = struct{}{}
continue nextEnum
}
if _, ok := KnownEnums[shortEnumName+"::"+ee.EntryName]; ok {
preventShortNames[e.EnumName] = struct{}{}
continue nextEnum
}
}
}
}
for _, e := range src.Enums {
if e.EnumName == "" {
continue // Removed by transformRedundant AST pass
}
goEnumName := cabiClassName(e.EnumName) // Fully qualified name of the enum itself
goEnumShortName := goEnumName // Shorter name, so that enum elements are reachable from the surrounding namespace
if _, ok := preventShortNames[e.EnumName]; !ok {
goEnumShortName = cabiClassName(e.ShortEnumName())
}
ret.WriteString(`
type ` + goEnumName + ` ` + e.UnderlyingType.RenderTypeGo(&gfs) + `
`)
if len(e.Entries) > 0 {
ret.WriteString("const (\n")
for _, ee := range e.Entries {
ret.WriteString(titleCase(cabiClassName(goEnumShortName+"::"+ee.EntryName)) + " " + goEnumName + " = " + ee.EntryValue + "\n")
}
ret.WriteString("\n)\n\n")
}
}
for _, c := range src.Classes {
goClassName := cabiClassName(c.ClassName)
// Type definition
ret.WriteString(`
type ` + goClassName + ` struct {
h *C.` + goClassName + `
isSubclass bool
`)
// Embed all inherited types to directly allow calling inherited methods
// Only include the direct inherits; the recursive inherits will exist
// on these types already
for _, base := range c.DirectInherits {
if strings.HasPrefix(base, `QList<`) {
ret.WriteString("/* Also inherits unprojectable " + base + " */\n")
} else if pkg, ok := KnownClassnames[base]; ok && pkg.PackageName != gfs.currentPackageName {
// Cross-package parent class
ret.WriteString("*" + path.Base(pkg.PackageName) + "." + cabiClassName(base) + "\n")
gfs.imports[importPathForQtPackage(pkg.PackageName)] = struct{}{}
} else {
// Same-package parent class
ret.WriteString("*" + cabiClassName(base) + "\n")
}
}
ret.WriteString(`
}
func (this *` + goClassName + `) cPointer() *C.` + goClassName + ` {
if this == nil {
return nil
}
return this.h
}
func (this *` + goClassName + `) UnsafePointer() unsafe.Pointer {
if this == nil {
return nil
}
return unsafe.Pointer(this.h)
}
`)
// CGO types only exist within the same Go file, so other Go files can't
// call this same private ctor function, unless it goes through unsafe.Pointer{}.
// This is probably because C types can possibly violate the ODR whereas
// that never happens in Go's type system.
gfs.imports["unsafe"] = struct{}{}
localInit := "h: h"
unsafeInit := "h: (*C." + goClassName + ")(h)"
extraCArgs := ""
extraUnsafeArgs := ""
// We require arguments for all inherits, but we only embed the direct inherits
// Any recursive inherits will be owned by the base
for _, base := range c.AllInherits() {
extraCArgs += ", h_" + cabiClassName(base) + " *C." + cabiClassName(base)
extraUnsafeArgs += ", h_" + cabiClassName(base) + " unsafe.Pointer"
}
for _, pkg := range c.DirectInheritClassInfo() {
ctorPrefix := ""
base := pkg.Class.ClassName
constructRequiresParams := pkg.Class.AllInherits()
var ixxParams []string = make([]string, 0, len(constructRequiresParams)+1)
ixxParams = append(ixxParams, "h_"+cabiClassName(base))
for _, grandchildInheritedClass := range constructRequiresParams {
ixxParams = append(ixxParams, "h_"+cabiClassName(grandchildInheritedClass))
}
if pkg.PackageName != gfs.currentPackageName {
ctorPrefix = path.Base(pkg.PackageName) + "."
localInit += ",\n" + cabiClassName(base) + ": " + ctorPrefix + "UnsafeNew" + cabiClassName(base) + "(unsafe.Pointer(" + strings.Join(ixxParams, "), unsafe.Pointer(") + "))"
} else {
localInit += ",\n" + cabiClassName(base) + ": new" + cabiClassName(base) + "(" + strings.Join(ixxParams, ", ") + ")"
}
unsafeInit += ",\n" + cabiClassName(base) + ": " + ctorPrefix + "UnsafeNew" + cabiClassName(base) + "(" + strings.Join(ixxParams, ", ") + ")"
}
ret.WriteString(`
// new` + goClassName + ` constructs the type using only CGO pointers.
func new` + goClassName + `(h *C.` + goClassName + extraCArgs + `) *` + goClassName + ` {
if h == nil {
return nil
}
return &` + goClassName + `{` + localInit + `}
}
// UnsafeNew` + goClassName + ` constructs the type using only unsafe pointers.
func UnsafeNew` + goClassName + `(h unsafe.Pointer` + extraUnsafeArgs + `) *` + goClassName + ` {
if h == nil {
return nil
}
return &` + goClassName + `{` + unsafeInit + `}
}
`)
//
for i, ctor := range c.Ctors {
preamble, forwarding := gfs.emitParametersGo2CABIForwarding(ctor)
ret.WriteString(`
// New` + goClassName + maybeSuffix(i) + ` constructs a new ` + c.ClassName + ` object.
func New` + goClassName + maybeSuffix(i) + `(` + gfs.emitParametersGo(ctor.Parameters) + `) *` + goClassName + ` {
`,
)
if ctor.LinuxOnly {
gfs.imports["runtime"] = struct{}{}
ret.WriteString(`
if runtime.GOOS != "linux" {
panic("Unsupported OS")
}
`)
}
ret.WriteString(preamble)
// Outptr management
outptrs := make([]string, 0, len(c.AllInherits())+1)
ret.WriteString(`var outptr_` + cabiClassName(c.ClassName) + ` *C.` + goClassName + " = nil\n")
outptrs = append(outptrs, "outptr_"+cabiClassName(c.ClassName))
for _, baseClass := range c.AllInherits() {
ret.WriteString(`var outptr_` + cabiClassName(baseClass) + ` *C.` + cabiClassName(baseClass) + " = nil\n")
outptrs = append(outptrs, "outptr_"+cabiClassName(baseClass))
}
if len(forwarding) > 0 {
forwarding += ", "
}
forwarding += "&" + strings.Join(outptrs, ", &")
// Call Cgo constructor
ret.WriteString(`
C.` + goClassName + `_new` + maybeSuffix(i) + `(` + forwarding + `)
ret := new` + goClassName + `(` + strings.Join(outptrs, `, `) + `)
ret.isSubclass = true
return ret
}
`)
}
for _, m := range c.Methods {
if m.IsProtected {
continue // Don't add a direct call for it
}
preamble, forwarding := gfs.emitParametersGo2CABIForwarding(m)
returnTypeDecl := m.ReturnType.renderReturnTypeGo(&gfs)
rvalue := `C.` + goClassName + `_` + m.SafeMethodName() + `(` + forwarding + `)`
returnFunc := gfs.emitCabiToGo("return ", m.ReturnType, rvalue)
receiverAndMethod := `(this *` + goClassName + `) ` + m.SafeMethodName()
if m.IsStatic {
receiverAndMethod = goClassName + `_` + m.SafeMethodName()
}
ret.WriteString(`
func ` + receiverAndMethod + `(` + gfs.emitParametersGo(m.Parameters) + `) ` + returnTypeDecl + ` {`)
if m.LinuxOnly {
gfs.imports["runtime"] = struct{}{}
ret.WriteString(`
if runtime.GOOS != "linux" {
panic("Unsupported OS")
}
`)
}
ret.WriteString(`
` + preamble +
returnFunc + `}
`)
// Add Connect() wrappers for signal functions
if m.IsSignal {
gfs.imports["unsafe"] = struct{}{}
gfs.imports["runtime/cgo"] = struct{}{}
var cgoNamedParams []string
var paramNames []string
conversion := ""
if len(m.Parameters) > 0 {
conversion = "// Convert all CABI parameters to Go parameters\n"
}
for i, pp := range m.Parameters {
cgoNamedParams = append(cgoNamedParams, pp.ParameterName+" "+pp.parameterTypeCgo())
paramNames = append(paramNames, fmt.Sprintf("slotval%d", i+1))
conversion += gfs.emitCabiToGo(fmt.Sprintf("slotval%d := ", i+1), pp, pp.ParameterName) + "\n"
}
goCbType := `func(` + gfs.emitParametersGo(m.Parameters) + `)`
ret.WriteString(`func (this *` + goClassName + `) On` + m.SafeMethodName() + `(slot ` + goCbType + `) {
C.` + goClassName + `_connect_` + m.SafeMethodName() + `(this.h, C.intptr_t(cgo.NewHandle(slot)) )
}
//export miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `
func miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `(cb C.intptr_t` + ifv(len(m.Parameters) > 0, ", ", "") + strings.Join(cgoNamedParams, `, `) + `) {
gofunc, ok := cgo.Handle(cb).Value().(` + goCbType + `)
if !ok {
panic("miqt: callback of non-callback type (heap corruption?)")
}
` + conversion + `
gofunc(` + strings.Join(paramNames, `, `) + ` )
}
`)
}
}
for _, m := range c.VirtualMethods() {
gfs.imports["unsafe"] = struct{}{}
gfs.imports["runtime/cgo"] = struct{}{}
// Add a package-private function to call the C++ base class method
// QWidget_virtualbase_PaintEvent
// This is only possible if the function is not pure-virtual
if !m.IsPureVirtual {
preamble, forwarding := gfs.emitParametersGo2CABIForwarding(m)
forwarding = "unsafe.Pointer(this.h)" + strings.TrimPrefix(forwarding, `this.h`) // TODO integrate properly
returnTypeDecl := m.ReturnType.renderReturnTypeGo(&gfs)
ret.WriteString(`
func (this *` + goClassName + `) callVirtualBase_` + m.SafeMethodName() + `(` + gfs.emitParametersGo(m.Parameters) + `) ` + returnTypeDecl + ` {
` + preamble + `
` + gfs.emitCabiToGo("return ", m.ReturnType, `C.`+goClassName+`_virtualbase_`+m.SafeMethodName()+`(`+forwarding+`)`) + `
}
`)
}
// Add a function to set the virtual override handle
// It must be possible to call the base class version, so pass
// that a as a 'super' callback as an extra parameter
{
var cgoNamedParams []string
var paramNames []string
if !m.IsPureVirtual {
paramNames = append(paramNames, "(&"+goClassName+"{h: self}).callVirtualBase_"+m.SafeMethodName())
}
conversion := ""
if len(m.Parameters) > 0 {
conversion = "// Convert all CABI parameters to Go parameters\n"
}
for i, pp := range m.Parameters {
cgoNamedParams = append(cgoNamedParams, pp.ParameterName+" "+pp.parameterTypeCgo())
paramNames = append(paramNames, fmt.Sprintf("slotval%d", i+1))
conversion += gfs.emitCabiToGo(fmt.Sprintf("slotval%d := ", i+1), pp, pp.ParameterName) + "\n"
}
cabiReturnType := m.ReturnType.parameterTypeCgo()
if cabiReturnType == "C.void" {
cabiReturnType = ""
}
superCbType := `func(` + gfs.emitParametersGo(m.Parameters) + `) ` + m.ReturnType.renderReturnTypeGo(&gfs)
goCbType := `func(`
if !m.IsPureVirtual {
goCbType += `super ` + superCbType
if len(m.Parameters) > 0 {
goCbType += `, `
}
}
goCbType += gfs.emitParametersGo(m.Parameters)
goCbType += `) ` + m.ReturnType.renderReturnTypeGo(&gfs)
ret.WriteString(`func (this *` + goClassName + `) On` + m.SafeMethodName() + `(slot ` + goCbType + `) {
C.` + goClassName + `_override_virtual_` + m.SafeMethodName() + `(unsafe.Pointer(this.h), C.intptr_t(cgo.NewHandle(slot)) )
}
//export miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `
func miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `(self *C.` + goClassName + `, cb C.intptr_t` + ifv(len(m.Parameters) > 0, ", ", "") + strings.Join(cgoNamedParams, `, `) + `) ` + cabiReturnType + `{
gofunc, ok := cgo.Handle(cb).Value().(` + goCbType + `)
if !ok {
panic("miqt: callback of non-callback type (heap corruption?)")
}
`)
ret.WriteString(conversion + "\n")
if cabiReturnType == "" {
ret.WriteString(`gofunc(` + strings.Join(paramNames, `, `) + " )\n")
} else {
ret.WriteString(`virtualReturn := gofunc(` + strings.Join(paramNames, `, `) + " )\n")
virtualRetP := m.ReturnType // copy
virtualRetP.ParameterName = "virtualReturn"
binding, rvalue := gfs.emitParameterGo2CABIForwarding(virtualRetP)
ret.WriteString(binding + "\n")
ret.WriteString("return " + rvalue + "\n")
}
ret.WriteString(`
}
`)
}
}
if c.CanDelete {
gfs.imports["runtime"] = struct{}{} // Finalizer
ret.WriteString(`
// Delete this object from C++ memory.
func (this *` + goClassName + `) Delete() {
C.` + goClassName + `_Delete(this.h, C.bool(this.isSubclass))
}
// GoGC adds a Go Finalizer to this pointer, so that it will be deleted
// from C++ memory once it is unreachable from Go memory.
func (this *` + goClassName + `) GoGC() {
runtime.SetFinalizer(this, func(this *` + goClassName + `) {
this.Delete()
runtime.KeepAlive(this.h)
})
}
`)
}
}
goSrc := ret.String()
// Fixup imports
if len(gfs.imports) > 0 {
allImports := make([]string, 0, len(gfs.imports))
for k := range gfs.imports {
if k == "libmiqt" {
allImports = append(allImports, `"`+BaseModule+`/libmiqt"`)
} else {
allImports = append(allImports, `"`+k+`"`)
}
}
sort.Strings(allImports)
goSrc = strings.Replace(goSrc, `%%_IMPORTLIBS_%%`, "import (\n\t"+strings.Join(allImports, "\n\t")+"\n)", 1)
} else {
goSrc = strings.Replace(goSrc, `%%_IMPORTLIBS_%%`, "", 1)
}
// Run gofmt over the result
formattedSrc, err := format.Source([]byte(goSrc))
if err != nil {
log.Printf("gofmt failure: %v", err)
formattedSrc = []byte(goSrc)
}
return string(formattedSrc), nil
}