Migrated util.go back and formalized pkguiAlloc().

datetimepicker.go

@@ -10,10 +10,10 @@ import (
 // #include <stdlib.h>
 // #include <time.h>
 // #include "ui.h"
+// #include "util.h"
 // static inline struct tm *allocTimeStruct(void)
 // {
-// 	/* TODO handle error */
-// 	return (struct tm *) malloc(sizeof (struct tm));
+// 	return (struct tm *) pkguiAlloc(sizeof (struct tm));
 // }
 // extern void doDateTimePickerOnChanged(uiDateTimePicker *, void *);
 import "C"

util.go

@@ -7,34 +7,26 @@ import (
 )
 
 // #include <stdlib.h>
-// // TODO remove when switching to Go 1.7
-// #include <string.h>
+// #include "util.h"
 import "C"
 
-// TODO move this to C.CBytes() when switching to Go 1.7
-
 // We want Go itself to complain when we're out of memory.
 // The allocators in cgo *should* do this, but there isn't a
 // C.CMalloc(). There *is* a C.CBytes(), however, for transferring
 // binary blobs from Go to C. If we pass this an arbitrary slice
 // of the desired length, we get our C.CMalloc(). Using a slice
-// that's always initialized to zero gives us the ZeroMemory()
-// for free.
-var uimallocBytes = make([]byte, 1024)		// 1024 bytes first
+// that's always initialized to zero gives us the memset(0)
+// (or ZeroMemory()) for free.
+var allocBytes = make([]byte, 1024)		// 1024 bytes first
 
-//export uimalloc
-func uimalloc(n C.size_t) unsafe.Pointer {
-	if n > C.size_t(len(uimallocBytes)) {
+//export pkguiAlloc
+func pkguiAlloc(n C.size_t) unsafe.Pointer {
+	if n > C.size_t(len(allocBytes)) {
 		// TODO round n up to a multiple of a power of 2?
 		// for instance 0x1234 bytes -> 0x1800 bytes
-		uimallocBytes = make([]byte, n)
+		allocBytes = make([]byte, n)
 	}
-	p := C.malloc(n)
-	if p == nil {
-		panic("out of memory in uimalloc()")
-	}
-	C.memset(p, 0, n)
-	return p
+	return C.CBytes(allocBytes[:n])
 }
 
 func freestr(str *C.char) {

util.h

@@ -0,0 +1,3 @@
+// 12 august 2018
+
+extern void *pkguiAlloc(size_t);