android: ipc -> ffi

This commit converts the stdin/stdout IPC interface to use FFI using
emulated stdin/stdout.

Signed-off-by: Sumner Evans <[email protected]>

.gitignore

@@ -17,3 +17,5 @@
 /beeper-imessage
 /start
 /.android-ipc-bin
+/imgo.h
+/imgo.so

android-ipc → android-ffi

@@ -3,6 +3,5 @@ set -e
 repo_dir=$(dirname $(realpath $0))
 pushd $repo_dir > /dev/null
 LDFLAGS="-X main.Tag=$(git describe --exact-match --tags 2>/dev/null) -X main.Commit=$(git rev-parse HEAD) -X 'main.BuildTime=$(date '+%b %_d %Y, %H:%M:%S')'"
-go build -ldflags "$LDFLAGS" -o .android-ipc-bin ./imessage/ipc/
+go build -ldflags "$LDFLAGS" -buildmode=c-shared -o imgo.so ./imessage/ffi/
 popd > /dev/null
-rlwrap -H "$HOME/.android-ipc_history" $repo_dir/.android-ipc-bin 2> >(zeroparse >&2) | (trap '' INT; jq -c)

android/imessage.sh

@@ -40,7 +40,7 @@ build_imessage() {
 
   (set -x; CGO_LDFLAGS="-lm -llog" CGO_ENABLED=1 GOOS=android GOARCH=$GOARCH GOARM=$GOARM \
   CC="$NDK_ROOT/toolchains/llvm/prebuilt/$NDK_ARCH/bin/$NDK_TARGET$ANDROID_API-clang" \
-  go build -ldflags "$LDFLAGS" -o "$LIB_JNI"/libima.so ./imessage/ipc)
+  go build -ldflags "$LDFLAGS" -o "$LIB_JNI"/libima.so ./imessage/ffi)
 }
 
 build_imessage armeabi-v7a armv7a-linux-androideabi arm 7

imessage/ipc/events.go → imessage/ffi/events.go

@@ -824,6 +824,10 @@ func handleDelivered(status *direct.MessageDelivered) {
 	}
 }
 
+type ReqStarted struct {
+	LoggedIn bool `json:"logged_in"`
+}
+
 func handleEvent(evt any) {
 	switch typedEvt := evt.(type) {
 	case *imessage.Message:

imessage/ipc/global.go → imessage/ffi/global.go

@@ -43,7 +43,7 @@ import (
 	"github.com/beeper/imessage/imessage/direct/ids"
 	"github.com/beeper/imessage/imessage/direct/nacserv"
 	"github.com/beeper/imessage/imessage/direct/util/httputil"
-	"github.com/beeper/imessage/imessage/ipc/imux"
+	"github.com/beeper/imessage/imessage/ffi/imux"
 	"github.com/beeper/imessage/ipc"
 	"github.com/beeper/imessage/msgconv"
 )

imessage/ipc/main.go → imessage/ffi/main.go

@@ -16,6 +16,7 @@
 
 package main
 
+import "C"
 import (
 	"context"
 	_ "embed"
@@ -89,8 +90,11 @@ func analyticsTrackOverIPC(event string, properties map[string]any) error {
 	})
 }
 
-func main() {
-	writer := ipc.NewLockedWriter(os.Stdout)
+func main() {}
+
+//export start
+func start() {
+	writer := ipc.NewLockedWriter(&FFIStdout)
 	zeroconfig.RegisterWriter(writerTypeStdoutIPC, func(config *zeroconfig.WriterConfig) (io.Writer, error) {
 		return writer, nil
 	})
@@ -121,7 +125,7 @@ func main() {
 	}
 
 	ipcLog := log.With().Str("component", "ipc").Logger()
-	global.IPC = ipc.NewProcessor(writer, os.Stdin, &ipcLog)
+	global.IPC = ipc.NewProcessor(writer, FFIStdinReader, &ipcLog)
 	global.IPC.SetHandler(CmdLogin, ipc.TypedHandler(fnLogin))
 	global.IPC.SetHandler(CmdMessage, ipc.TypedHandler(fnMessage))
 	global.IPC.SetHandler(CmdMultipartMessage, ipc.TypedHandler(fnMultipartMessage))
@@ -228,7 +232,6 @@ func main() {
 		log.Err(err).Msg("Failed to close database")
 	}
 	log.Info().Msg("Shutdown preparations complete, exiting")
-	os.Exit(0)
 }
 
 func initialConfigure(ctx context.Context) {

imessage/ffi/stdin.go

@@ -0,0 +1,41 @@
+// beeper-imessage - A Matrix-iMessage puppeting bridge.
+// Copyright (C) 2023 Beeper, Inc.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package main
+
+import "C"
+import (
+	"io"
+	"unsafe"
+)
+
+var FFIStdinReader, FFIStdinWriter = io.Pipe()
+
+// stdin_write is a function which allows C code to write to the fake "stdin"
+// buffer.
+//
+// This function returns the number of bytes written, or -1 if an error
+// occurred.
+//
+//export stdin_write
+func stdin_write(data *C.char, n C.int) C.int {
+	buf := C.GoBytes(unsafe.Pointer(data), n)
+	written, err := FFIStdinWriter.Write(buf)
+	if err != nil {
+		return C.int(-1)
+	}
+	return C.int(written)
+}

imessage/ffi/stdout.c

@@ -0,0 +1,7 @@
+#include <stdio.h>
+
+typedef void (*stdout_callback_t)(const char *, int);
+
+void stdout_write(stdout_callback_t callback, const char *data, int n) {
+  callback(data, n);
+}

imessage/ffi/stdout.go

@@ -0,0 +1,44 @@
+// beeper-imessage - A Matrix-iMessage puppeting bridge.
+// Copyright (C) 2023 Beeper, Inc.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package main
+
+/*
+#include <stdio.h>
+
+// stdout_callback is a function pointer to a function that takes a string and
+// returns nothing.
+typedef void (*stdout_callback_t)(const char*, int);
+void stdout_write(stdout_callback_t callback, const char* data, int n);
+*/
+import "C"
+import "unsafe"
+
+type ffiStdout struct {
+	callback C.stdout_callback_t
+}
+
+func (s *ffiStdout) Write(p []byte) (n int, err error) {
+	C.stdout_write(s.callback, (*C.char)(unsafe.Pointer(&p[0])), C.int(len(p)))
+	return len(p), nil
+}
+
+var FFIStdout = ffiStdout{}
+
+//export set_stdout_callback
+func set_stdout_callback(callback C.stdout_callback_t) {
+	FFIStdout.callback = callback
+}