From: mural <mural@ctli.io>
To: ~eliasnaur/gio-patches@lists.sr.ht
Cc: mural <mural@ctli.io>
Subject: [gio v1] app/internal/log: add logger for Windows DebugView
Date: Mon, 13 Jan 2020 19:43:55 +0800
Message-Id: <20200113114355.17505-1-mural@ctli.io>
In-Reply-To: <BZSA0XKTYNO0.1A2TNG8GE6WTU@toolbox>
References: <BZSA0XKTYNO0.1A2TNG8GE6WTU@toolbox>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable

Signed-off-by: mural <mural@ctli.io>
---
According to
https://docs.microsoft.com/en-us/windows/console/getstdhandle,
GetStdHandle would return NULL if there is no associated standard handles=
.
So we chack 0 as well.

 app/internal/log/log_windows.go | 34 +++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 app/internal/log/log_windows.go

diff --git a/app/internal/log/log_windows.go b/app/internal/log/log_windo=
ws.go
new file mode 100644
index 0000000..0642919
--- /dev/null
+++ b/app/internal/log/log_windows.go
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package log
+
+import (
+	"log"
+	"syscall"
+	"unsafe"
+)
+
+type logger struct{}
+
+var (
+	kernel32           =3D syscall.NewLazyDLL("kernel32")
+	outputDebugStringW =3D kernel32.NewProc("OutputDebugStringW")
+	debugView          *logger
+)
+
+func init() {
+	// Windows DebugView already includes timestamps.
+	if syscall.Stderr =3D=3D 0 || syscall.Stderr =3D=3D syscall.InvalidHand=
le {
+		log.SetFlags(log.Flags() &^ log.LstdFlags)
+		log.SetOutput(debugView)
+	}
+}
+
+func (l *logger) Write(buf []byte) (int, error) {
+	p, err :=3D syscall.UTF16PtrFromString(string(buf))
+	if err !=3D nil {
+		return 0, err
+	}
+	outputDebugStringW.Call(uintptr(unsafe.Pointer(p)))
+	return len(buf), nil
+}
--=20
2.24.1