gio: app/internal/log: add logger for Windows DebugView v1 PROPOSED

~typeless: 1
 app/internal/log: add logger for Windows DebugView

 1 files changed, 32 insertions(+), 0 deletions(-)

[PATCH gio] app/internal/log: add logger for Windows DebugView Export this patch

From: mural <mural@ctli.io>

Signed-off-by: mural <mural@ctli.io>
---
 app/internal/log/log_windows.go | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 app/internal/log/log_windows.go

diff --git a/app/internal/log/log_windows.go b/app/internal/log/log_windows.go
new file mode 100644
index 0000000..c7691d2
--- /dev/null
+++ b/app/internal/log/log_windows.go
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package log
+
+import (
+	"log"
+	"syscall"
+	"unsafe"
+)
+
+type logger struct{}
+
+var (
+	kernel32           = syscall.NewLazyDLL("kernel32")
+	outputDebugStringW = kernel32.NewProc("OutputDebugStringW")
+	out                logger
+)
+
+func init() {
+	// Windows DbgView already includes timestamps.
+	log.SetFlags(log.Flags() &^ log.LstdFlags)
+	log.SetOutput(&out)
+}
+
+func (l *logger) Write(buf []byte) (int, error) {
+	p, err := syscall.UTF16PtrFromString(string(buf))
+	if err != nil {
+		return 0, err
+	}
+	outputDebugStringW.Call(uintptr(unsafe.Pointer(p)))
+	return len(buf), nil
+}
-- 
2.24.1