Move a few things to an internal util package for use by more things

Author: Matt Peterson

bridge.go

@@ -20,6 +20,7 @@ import (
 	"unsafe"
 
 	"github.com/limetext/qml-go/cdata"
+	"github.com/limetext/qml-go/internal/util"
 )
 
 type mainThreadFunc struct {
@@ -240,7 +241,7 @@ const (
 func wrapGoValue(engine *Engine, gvalue interface{}, owner valueOwner) (cvalue unsafe.Pointer) {
 	gvaluev := reflect.ValueOf(gvalue)
 	gvaluek := gvaluev.Kind()
-	if gvaluek == reflect.Struct && !hashable(gvalue) {
+	if gvaluek == reflect.Struct && !util.Hashable(gvalue) {
 		name := gvaluev.Type().Name()
 		if name != "" {
 			name = " (" + name + ")"
@@ -256,7 +257,7 @@ func wrapGoValue(engine *Engine, gvalue interface{}, owner valueOwner) (cvalue u
 	hashableGvalue := gvalue
 	if gvaluev.Kind() == reflect.Slice {
 		hashableGvalue = *(*reflect.SliceHeader)(unsafe.Pointer(gvaluev.Pointer()))
-	} else if !hashable(gvalue) {
+	} else if !util.Hashable(gvalue) {
 		panic(fmt.Sprintf("gvalue not hashable: %v %v", gvaluev.Type(), gvaluev.Kind()))
 	}
 
@@ -424,7 +425,7 @@ func hookGoValueReadField(enginep, foldp unsafe.Pointer, reflectIndex, getIndex,
 	if fieldk == reflect.Slice || fieldk == reflect.Struct && field.Type() != typeRGBA {
 		if field.CanAddr() {
 			field = field.Addr()
-		} else if !hashable(field.Interface()) {
+		} else if !util.Hashable(field.Interface()) {
 			t := reflect.ValueOf(fold.gvalue).Type()
 			for t.Kind() == reflect.Ptr {
 				t = t.Elem()

cpp/capi.h

@@ -106,6 +106,7 @@ typedef struct {
     int line;
 } LogMessage;
 
+
 void newGuiApplication();
 void applicationExec();
 void applicationExit();
@@ -117,6 +118,7 @@ void idleTimerStart();
 void *currentThread();
 void *appThread();
 
+
 QQmlEngine_ *newEngine(QObject_ *parent);
 QQmlContext_ *engineRootContext(QQmlEngine_ *engine);
 void engineSetOwnershipCPP(QQmlEngine_ *engine, QObject_ *object);
@@ -128,6 +130,7 @@ void engineAddImportPath(QQmlEngine_ *engine, const char *path, int pathLen);
 void engineClearPluginPaths(QQmlEngine_ *engine);
 void engineAddPluginPath(QQmlEngine_ *engine, const char *path, int pathLen);
 void engineClearComponentCache(QQmlEngine_ *engine);
+
 void coreAddLibraryPath(const char *path, int pathLen);
 
 void contextGetProperty(QQmlContext_ *context, QString_ *name, DataValue *value);

datatype.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 	"unicode"
 	"unsafe"
+	"github.com/limetext/qml-go/internal/util"
 )
 
 var (
@@ -70,9 +71,9 @@ func packDataValue(value interface{}, dvalue *C.DataValue, engine *Engine, owner
 	switch value := value.(type) {
 	case string:
 		dvalue.dataType = C.DTString
-		cstr, cstrlen := unsafeStringData(value)
-		*(**C.char)(datap) = cstr
-		dvalue.len = cstrlen
+		cstr, cstrlen := util.UnsafeStringData(value)
+		*(**C.char)(datap) = (*C.char)(cstr)
+		dvalue.len = C.int(cstrlen)
 	case bool:
 		dvalue.dataType = C.DTBool
 		*(*bool)(datap) = value
@@ -225,8 +226,8 @@ func dataTypeOf(typ reflect.Type) C.DataType {
 	return C.DTObject
 }
 
-var typeInfoSize = C.size_t(unsafe.Sizeof(C.GoTypeInfo{}))
-var memberInfoSize = C.size_t(unsafe.Sizeof(C.GoMemberInfo{}))
+const typeInfoSize = C.size_t(C.sizeof_GoTypeInfo)
+const memberInfoSize = C.size_t(C.sizeof_GoMemberInfo)
 
 var typeInfoCache = make(map[reflect.Type]*C.GoTypeInfo)
 
@@ -480,49 +481,3 @@ func methodQtSignature(method reflect.Method) (signature, result string) {
 	}
 	return
 }
-
-func hashable(value interface{}) (hashable bool) {
-	defer func() { recover() }()
-	return value == value
-}
-
-// unsafeString returns a Go string backed by C data.
-//
-// If the C data is deallocated or moved, the string will be
-// invalid and will crash the program if used. As such, the
-// resulting string must only be used inside the implementation
-// of the qml package and while the life time of the C data
-// is guaranteed.
-func unsafeString(data *C.char, size C.int) string {
-	var s string
-	sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
-	sh.Data = uintptr(unsafe.Pointer(data))
-	sh.Len = int(size)
-	return s
-}
-
-// unsafeStringData returns a C string backed by Go data. The C
-// string is NOT null-terminated, so its length must be taken
-// into account.
-//
-// If the s Go string is garbage collected, the returned C data
-// will be invalid and will crash the program if used. As such,
-// the resulting data must only be used inside the implementation
-// of the qml package and while the life time of the Go string
-// is guaranteed.
-func unsafeStringData(s string) (*C.char, C.int) {
-	return *(**C.char)(unsafe.Pointer(&s)), C.int(len(s))
-}
-
-// unsafeBytesData returns a C string backed by Go data. The C
-// string is NOT null-terminated, so its length must be taken
-// into account.
-//
-// If the array backing the b Go slice is garbage collected, the
-// returned C data will be invalid and will crash the program if
-// used. As such, the resulting data must only be used inside the
-// implementation of the qml package and while the life time of
-// the Go array is guaranteed.
-func unsafeBytesData(b []byte) (*C.char, C.int) {
-	return *(**C.char)(unsafe.Pointer(&b)), C.int(len(b))
-}

internal/util/util.go

@@ -0,0 +1,53 @@
+package util
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+func Hashable(value interface{}) (hashable bool) {
+	defer func() { recover() }()
+	return value == value
+}
+
+// unsafeString returns a Go string backed by C data.
+//
+// If the C data is deallocated or moved, the string will be
+// invalid and will crash the program if used. As such, the
+// resulting string must only be used inside the implementation
+// of the qml package and while the life time of the C data
+// is guaranteed.
+func UnsafeString(data unsafe.Pointer, size int) string {
+	var s string
+	sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
+	sh.Data = uintptr(data)
+	sh.Len = size
+	return s
+}
+
+// unsafeStringData returns a C string backed by Go data. The C
+// string is NOT null-terminated, so its length must be taken
+// into account.
+//
+// If the s Go string is garbage collected, the returned C data
+// will be invalid and will crash the program if used. As such,
+// the resulting data must only be used inside the implementation
+// of the qml package and while the life time of the Go string
+// is guaranteed.
+func UnsafeStringData(s string) (unsafe.Pointer, int) {
+	sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
+	return unsafe.Pointer(sh.Data), sh.Len
+}
+
+// unsafeBytesData returns a C string backed by Go data. The C
+// string is NOT null-terminated, so its length must be taken
+// into account.
+//
+// If the array backing the b Go slice is garbage collected, the
+// returned C data will be invalid and will crash the program if
+// used. As such, the resulting data must only be used inside the
+// implementation of the qml package and while the life time of
+// the Go array is guaranteed.
+func UnsafeBytesData(b []byte) (unsafe.Pointer, int) {
+	return *(*unsafe.Pointer)(unsafe.Pointer(&b)), len(b)
+}

log.go

@@ -9,6 +9,9 @@ import (
 	"log"
 	"path/filepath"
 	"strings"
+	"unsafe"
+
+	"github.com/limetext/qml-go/internal/util"
 )
 
 // SetLogger sets the target for messages logged by the qml package,
@@ -97,7 +100,7 @@ func init() {
 //export hookLogHandler
 func hookLogHandler(cmsg *C.LogMessage) {
 	// Workarund for QTBUG-35943
-	text := unsafeString(cmsg.text, cmsg.textLen)
+	text := util.UnsafeString(unsafe.Pointer(cmsg.text), int(cmsg.textLen))
 	if strings.HasPrefix(text, `"Qt Warning: Compose file:`) {
 		return
 	}
@@ -139,8 +142,8 @@ func (m *logMessage) Line() int {
 
 func (m *logMessage) String() string {
 	m.assertValid()
-	file := unsafeString(m.c.file, m.c.fileLen)
-	text := unsafeString(m.c.text, m.c.textLen)
+	file := util.UnsafeString(unsafe.Pointer(m.c.file), int(m.c.fileLen))
+	text := util.UnsafeString(unsafe.Pointer(m.c.text), int(m.c.textLen))
 	return fmt.Sprintf("%s:%d: %s", filepath.Base(file), m.c.line, text)
 }
 

qml.go

@@ -9,12 +9,14 @@ import "C"
 import (
 	"errors"
 	"unsafe"
+
+	"github.com/limetext/qml-go/internal/util"
 )
 
 func AddLibraryPath(path string) {
-	cpath, cpathLen := unsafeStringData(path)
+	cpath, cpathLen := util.UnsafeStringData(path)
 	RunMain(func() {
-		C.coreAddLibraryPath(cpath, cpathLen)
+		C.coreAddLibraryPath((*C.char)(cpath), C.int(cpathLen))
 	})
 }
 

qmlcommon.go

@@ -11,7 +11,10 @@ import (
 	"image/color"
 	"os"
 	"reflect"
+	"runtime/debug"
 	"unsafe"
+
+	"github.com/limetext/qml-go/internal/util"
 )
 
 // Common implements the common behavior of all QML objects.
@@ -274,11 +277,11 @@ func (obj *Common) Map(property string) *Map {
 // ObjectByName panics if the object is not found.
 func (obj *Common) ObjectByName(objectName string) Object {
 	obj.assertInitialized()
-	cname, cnamelen := unsafeStringData(objectName)
+	cname, cnamelen := util.UnsafeStringData(objectName)
 	var dvalue C.DataValue
 	var object Object
 	RunMain(func() {
-		qname := C.newString(cname, cnamelen)
+		qname := C.newString((*C.char)(cname), C.int(cnamelen))
 		defer C.delString(qname)
 		C.objectFindChild(obj.addr, qname, &dvalue)
 		// unpackDataValue will also initialize the Go type, if necessary.
@@ -308,7 +311,7 @@ func (obj *Common) Call(method string, params ...interface{}) interface{} {
 	if len(params) > len(dataValueArray) {
 		panic("too many parameters")
 	}
-	cmethod, cmethodLen := unsafeStringData(method)
+	cmethod, cmethodLen := util.UnsafeStringData(method)
 	var result C.DataValue
 	var cerr *C.error
 	RunMain(func() {
@@ -328,7 +331,7 @@ func (obj *Common) Call(method string, params ...interface{}) interface{} {
 			// destroyed while waiting to run on the main thread
 			// TODO: What to do about this???
 		}
-		cerr = C.objectInvoke(obj.addr, cmethod, cmethodLen, &result, &dataValueArray[0], C.int(len(params)))
+		cerr = C.objectInvoke(obj.addr, (*C.char)(cmethod), C.int(cmethodLen), &result, &dataValueArray[0], C.int(len(params)))
 	})
 	if cerr != nil {
 		fmt.Fprintf(os.Stderr, "Common: %#v\n", obj)
@@ -429,10 +432,10 @@ func (obj *Common) On(signal string, function interface{}) {
 	if funct.NumIn() > C.MaxParams {
 		panic("function takes too many arguments")
 	}
-	csignal, csignallen := unsafeStringData(signal)
+	csignal, csignallen := util.UnsafeStringData(signal)
 	var cerr *C.error
 	RunMain(func() {
-		cerr = C.objectConnect(obj.addr, csignal, csignallen, obj.engine.addr, unsafe.Pointer(&function), C.int(funcv.Type().NumIn()))
+		cerr = C.objectConnect(obj.addr, (*C.char)(csignal), C.int(csignallen), obj.engine.addr, unsafe.Pointer(&function), C.int(funcv.Type().NumIn()))
 		if cerr == nil {
 			connectedFunction[&function] = true
 			stats.connectionsAlive(+1)

qmlcontext.go

@@ -5,6 +5,9 @@ package qml
 // #include "capi.h"
 //
 import "C"
+import (
+	"github.com/limetext/qml-go/internal/util"
+)
 
 // Context represents a QML context that can hold variables visible
 // to logic running within it.
@@ -25,12 +28,12 @@ type Context struct {
 // not be garbage collected until the engine is destroyed, even if the
 // value is unused or changed.
 func (ctx *Context) SetVar(name string, value interface{}) {
-	cname, cnamelen := unsafeStringData(name)
+	cname, cnamelen := util.UnsafeStringData(name)
 	RunMain(func() {
 		var dvalue C.DataValue
 		packDataValue(value, &dvalue, ctx.engine, cppOwner)
 
-		qname := C.newString(cname, cnamelen)
+		qname := C.newString((*C.char)(cname), C.int(cnamelen))
 		defer C.delString(qname)
 
 		C.contextSetProperty(ctx.addr, qname, &dvalue)
@@ -54,11 +57,11 @@ func (ctx *Context) SetVars(value interface{}) {
 
 // Var returns the context variable with the given name.
 func (ctx *Context) Var(name string) interface{} {
-	cname, cnamelen := unsafeStringData(name)
+	cname, cnamelen := util.UnsafeStringData(name)
 
 	var dvalue C.DataValue
 	RunMain(func() {
-		qname := C.newString(cname, cnamelen)
+		qname := C.newString((*C.char)(cname), C.int(cnamelen))
 		defer C.delString(qname)
 
 		C.contextGetProperty(ctx.addr, qname, &dvalue)