From cfea745dc745dcb0af8704d7cdb50d9725714b04 Mon Sep 17 00:00:00 2001 From: Pietro Gagliardi Date: Sun, 12 Aug 2018 10:24:24 -0400 Subject: Migrated util.go back and formalized pkguiAlloc(). --- util.go | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 util.go (limited to 'util.go') diff --git a/util.go b/util.go new file mode 100644 index 0000000..bcd4d33 --- /dev/null +++ b/util.go @@ -0,0 +1,45 @@ +// 12 december 2015 + +package ui + +import ( + "unsafe" +) + +// #include +// #include "util.h" +import "C" + +// 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 memset(0) +// (or ZeroMemory()) for free. +var allocBytes = make([]byte, 1024) // 1024 bytes first + +//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 + allocBytes = make([]byte, n) + } + return C.CBytes(allocBytes[:n]) +} + +func freestr(str *C.char) { + C.free(unsafe.Pointer(str)) +} + +func tobool(b C.int) bool { + return b != 0 +} + +func frombool(b bool) C.int { + if b { + return 1 + } + return 0 +} -- cgit v1.2.3