genbindings: handle signal arguments from cabi->go

This commit is contained in:
mappu 2024-09-14 20:32:55 +12:00
parent 7f56b4147c
commit 6af39e88e4

View File

@ -2,6 +2,7 @@ package main
import (
"C"
"fmt"
"go/format"
"log"
"sort"
@ -275,6 +276,110 @@ func (gfs *goFileState) emitParametersGo2CABIForwarding(m CppMethod) (preamble s
return preamble, strings.Join(tmp, ", ")
}
func (gfs *goFileState) emitCabiToGo(assignExpr string, rt CppParameter, rvalue string) string {
shouldReturn := "return "
afterword := ""
namePrefix := rt.ParameterName
if rt.ParameterType == "void" && !rt.Pointer {
shouldReturn = ""
} else if rt.ParameterType == "void" && rt.Pointer {
// ...
} 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
gfs.imports["unsafe"] = struct{}{}
shouldReturn = namePrefix + "_ret := "
afterword += assignExpr + " (unsafe.Pointer)(" + namePrefix + "_ret)\n"
} else if rt.ParameterType == "QString" {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_ms *C.struct_miqt_string = "
afterword += "ret := C.GoStringN(&" + namePrefix + "_ms.data, C.int(int64(" + namePrefix + "_ms.len)))\n"
afterword += "C.free(unsafe.Pointer(" + namePrefix + "_ms))\n"
afterword += assignExpr + " ret"
} else if t, ok := rt.QListOf(); ok {
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var " + namePrefix + "_ma *C.struct_miqt_array = "
if t.ParameterType == "QString" {
// Combo
afterword += namePrefix + "_ret := make([]string, int(" + namePrefix + "_ma.len))\n"
afterword += "_outCast := (*[0xffff]*C.struct_miqt_string)(unsafe.Pointer(" + namePrefix + "_ma.data)) // hey ya\n"
afterword += "for i := 0; i < int(" + namePrefix + "_ma.len); i++ {\n"
afterword += "ret[i] = C.GoStringN(&_outCast[i].data, C.int(int64(_outCast[i].len)))\n"
afterword += "C.free(unsafe.Pointer(_outCast[i])) // free the inner miqt_string*\n"
afterword += "}\n"
afterword += "C.free(unsafe.Pointer(" + namePrefix + "_ma))\n"
afterword += assignExpr + " " + namePrefix + "_ret\n"
} else {
afterword += "" + namePrefix + "_ret := make([]" + t.RenderTypeGo() + ", int(" + namePrefix + "_ma.len))\n"
if t.QtClassType() {
afterword += "_outCast := (*[0xffff]*" + t.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_ma.data)) // so fresh so clean\n"
} else {
afterword += "_outCast := (*[0xffff]" + t.parameterTypeCgo() + ")(unsafe.Pointer(" + namePrefix + "_ma.data)) // mrs jackson\n"
}
afterword += "for i := 0; i < int(" + namePrefix + "_ma.len); i++ {\n"
if t.QtClassType() {
if !t.Pointer {
// new, but then dereference it
afterword += "" + namePrefix + "_ret[i] = *new" + cabiClassName(t.ParameterType) + "(_outCast[i])\n"
} else {
afterword += "" + namePrefix + "_ret[i] = new" + cabiClassName(t.ParameterType) + "(_outCast[i])\n"
}
} else { // plain int type
afterword += "" + namePrefix + "_ret[i] = (" + t.RenderTypeGo() + ")(_outCast[i])\n"
}
afterword += "}\n"
afterword += "C.free(unsafe.Pointer(" + namePrefix + "_ma))\n"
afterword += assignExpr + " " + namePrefix + "_ret\n"
}
} else if rt.QtClassType() {
// Construct our Go type based on this inner CABI type
shouldReturn = "" + namePrefix + "_ret := "
if rt.Pointer || rt.ByRef {
gfs.imports["unsafe"] = struct{}{}
afterword = assignExpr + " new" + cabiClassName(rt.ParameterType) + "_U(unsafe.Pointer(" + namePrefix + "_ret))"
} 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
gfs.imports["runtime"] = struct{}{}
afterword = "// Qt uses pass-by-value semantics for this type. Mimic with finalizer\n"
afterword += "" + namePrefix + "_ret1 := new" + cabiClassName(rt.ParameterType) + "(" + namePrefix + "_ret)\n"
afterword += "runtime.SetFinalizer(" + namePrefix + "_ret1, func(" + namePrefix + "_ret2 *" + cabiClassName(rt.ParameterType) + ") {\n"
afterword += "" + namePrefix + "_ret2.Delete()\n"
afterword += "runtime.KeepAlive(" + namePrefix + "_ret2.h)\n"
afterword += "})\n"
afterword += assignExpr + "" + namePrefix + "_ret1\n"
}
} else if rt.IntType() || rt.ParameterType == "bool" {
// Need to cast Cgo type to Go int type
shouldReturn = "" + namePrefix + "_ret := "
afterword += assignExpr + "(" + rt.RenderTypeGo() + ")(" + namePrefix + "_ret)\n"
}
return shouldReturn + " " + rvalue + "\n" + afterword
}
func emitGo(src *CppParsedHeader, headerName string) (string, error) {
ret := strings.Builder{}
@ -397,140 +502,42 @@ import "C"
for _, m := range c.Methods {
preamble, forwarding := gfs.emitParametersGo2CABIForwarding(m)
shouldReturn := "return "
afterword := ""
returnTypeDecl := m.ReturnType.RenderTypeGo() // FIXME handle byRef/const here too
if m.ReturnType.ParameterType == "void" && !m.ReturnType.Pointer {
shouldReturn = ""
returnTypeDecl := m.ReturnType.RenderTypeGo()
if returnTypeDecl == "void" {
returnTypeDecl = ""
} else if m.ReturnType.ParameterType == "void" && m.ReturnType.Pointer {
returnTypeDecl = "interface{}"
} else if m.ReturnType.ParameterType == "char" && m.ReturnType.Pointer {
// Qt functions normally return QString - anything returning char*
// is something like QByteArray.Data() where it returns an unsafe
// internal pointer
}
if m.ReturnType.QtClassType() && m.ReturnType.ParameterType != "QString" && !(m.ReturnType.Pointer || m.ReturnType.ByRef) {
returnTypeDecl = "*" + returnTypeDecl
}
if (m.ReturnType.ParameterType == "char" || m.ReturnType.ParameterType == "void") && m.ReturnType.Pointer {
gfs.imports["unsafe"] = struct{}{}
returnTypeDecl = "unsafe.Pointer"
shouldReturn = "ret := "
afterword += "return (unsafe.Pointer)(ret)\n"
} else if m.ReturnType.ParameterType == "QString" {
returnTypeDecl = "string"
gfs.imports["unsafe"] = struct{}{}
shouldReturn = "var ret_ms *C.struct_miqt_string = "
afterword += "ret := C.GoStringN(&ret_ms.data, C.int(int64(ret_ms.len)))\n"
afterword += "C.free(unsafe.Pointer(ret_ms))\n"
afterword += "return ret"
} else if t, ok := m.ReturnType.QListOf(); ok {
gfs.imports["unsafe"] = struct{}{}
returnTypeDecl = "[]" + t.RenderTypeGo()
shouldReturn = "var ret_ma *C.struct_miqt_array = "
if t.ParameterType == "QString" {
// Combo
afterword += "ret := make([]string, int(ret_ma.len))\n"
afterword += "_outCast := (*[0xffff]*C.struct_miqt_string)(unsafe.Pointer(ret_ma.data)) // hey ya\n"
afterword += "for i := 0; i < int(ret_ma.len); i++ {\n"
afterword += "ret[i] = C.GoStringN(&_outCast[i].data, C.int(int64(_outCast[i].len)))\n"
afterword += "C.free(unsafe.Pointer(_outCast[i])) // free the inner miqt_string*\n"
afterword += "}\n"
afterword += "C.free(unsafe.Pointer(ret_ma))\n"
afterword += "return ret\n"
} else {
afterword += "ret := make([]" + t.RenderTypeGo() + ", int(ret_ma.len))\n"
if t.QtClassType() {
afterword += "_outCast := (*[0xffff]*" + t.parameterTypeCgo() + ")(unsafe.Pointer(ret_ma.data)) // so fresh so clean\n"
} else {
afterword += "_outCast := (*[0xffff]" + t.parameterTypeCgo() + ")(unsafe.Pointer(ret_ma.data)) // mrs jackson\n"
}
afterword += "for i := 0; i < int(ret_ma.len); i++ {\n"
if t.QtClassType() {
if !t.Pointer {
// new, but then dereference it
afterword += "ret[i] = *new" + cabiClassName(t.ParameterType) + "(_outCast[i])\n"
} else {
afterword += "ret[i] = new" + cabiClassName(t.ParameterType) + "(_outCast[i])\n"
}
} else { // plain int type
afterword += "ret[i] = (" + t.RenderTypeGo() + ")(_outCast[i])\n"
}
afterword += "}\n"
afterword += "C.free(unsafe.Pointer(ret_ma))\n"
afterword += "return ret\n"
}
} else if m.ReturnType.QtClassType() {
// Construct our Go type based on this inner CABI type
shouldReturn = "ret := "
if m.ReturnType.Pointer || m.ReturnType.ByRef {
gfs.imports["unsafe"] = struct{}{}
afterword = "return new" + cabiClassName(m.ReturnType.ParameterType) + "_U(unsafe.Pointer(ret))"
} 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
returnTypeDecl = "*" + returnTypeDecl
gfs.imports["runtime"] = struct{}{}
afterword = "// Qt uses pass-by-value semantics for this type. Mimic with finalizer\n"
afterword += "ret1 := new" + cabiClassName(m.ReturnType.ParameterType) + "(ret)\n"
afterword += "runtime.SetFinalizer(ret1, func(ret2 *" + cabiClassName(m.ReturnType.ParameterType) + ") {\n"
afterword += "ret2.Delete()\n"
afterword += "runtime.KeepAlive(ret2.h)\n"
afterword += "})\n"
afterword += "return ret1\n"
}
} else if m.ReturnType.IntType() || m.ReturnType.ParameterType == "bool" {
// Need to cast Cgo type to Go int type
shouldReturn = "ret := "
afterword += "return (" + m.ReturnType.RenderTypeGo() + ")(ret)\n"
}
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 + `(` + emitParametersGo(m.Parameters) + `) ` + returnTypeDecl + ` {`)
if m.LinuxOnly {
gfs.imports["runtime"] = struct{}{}
ret.WriteString(`
func ` + receiverAndMethod + `(` + emitParametersGo(m.Parameters) + `) ` + returnTypeDecl + ` {
if runtime.GOOS == "linux" {
` + preamble +
shouldReturn + ` C.` + goClassName + `_` + m.SafeMethodName() + `(` + forwarding + `)
` + afterword + `
} else {
if runtime.GOOS != "linux" {
panic("Unsupported OS")
}
`)
}
`)
} else {
ret.WriteString(`
func ` + receiverAndMethod + `(` + emitParametersGo(m.Parameters) + `) ` + returnTypeDecl + ` {
ret.WriteString(`
` + preamble +
shouldReturn + ` C.` + goClassName + `_` + m.SafeMethodName() + `(` + forwarding + `)
` + afterword + `}
returnFunc + `}
`)
}
// Add Connect() wrappers for signal functions
if m.IsSignal {
gfs.imports["unsafe"] = struct{}{}
@ -538,31 +545,34 @@ import "C"
var cgoNamedParams []string
var paramNames []string
for _, pp := range m.Parameters {
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, pp.ParameterName)
paramNames = append(paramNames, fmt.Sprintf("slotval%d", i+1))
conversion += gfs.emitCabiToGo(fmt.Sprintf("slotval%d := ", i+1), pp, pp.ParameterName) + "\n"
}
ret.WriteString(`func (this *` + goClassName + `) On` + m.SafeMethodName() + `(slot func(` + emitParametersGo(m.Parameters) + `)) {
slotWrapper := func(` + strings.Join(cgoNamedParams, `, `) + `) {
// TODO convert CABI parameters to Go parameters here
slot()
}
C.` + goClassName + `_connect_` + m.SafeMethodName() + `(this.h, unsafe.Pointer(uintptr(cgo.NewHandle(slotWrapper))))
C.` + goClassName + `_connect_` + m.SafeMethodName() + `(this.h, unsafe.Pointer(uintptr(cgo.NewHandle(slot))))
}
//export miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `
func miqt_exec_callback_` + goClassName + `_` + m.SafeMethodName() + `(cb *C.void` + ifv(len(m.Parameters) > 0, ", ", "") + strings.Join(cgoNamedParams, `, `) + `) {
cfunc, ok := (cgo.Handle(uintptr(unsafe.Pointer(cb))).Value()).(func(` + strings.Join(cgoNamedParams, `, `) + `))
gofunc, ok := (cgo.Handle(uintptr(unsafe.Pointer(cb))).Value()).(func(` + emitParametersGo(m.Parameters) + `))
if !ok {
panic("miqt: callback of non-callback type (heap corruption?)")
}
cfunc(` + strings.Join(paramNames, `, `) + ` )
` + conversion + `
gofunc(` + strings.Join(paramNames, `, `) + ` )
}
`)
}
}