Add device event receiver

Create a separate component to handle device events, managed by the
controller.

app/meson.build

@@ -12,6 +12,7 @@ src = [
     'src/input_manager.c',
     'src/lock_util.c',
     'src/net.c',
+    'src/receiver.c',
     'src/recorder.c',
     'src/scrcpy.c',
     'src/screen.c',

app/src/controller.c

@@ -10,11 +10,17 @@ bool
 controller_init(struct controller *controller, socket_t control_socket) {
     cbuf_init(&controller->queue);
 
+    if (!receiver_init(&controller->receiver, control_socket)) {
+        return false;
+    }
+
     if (!(controller->mutex = SDL_CreateMutex())) {
+        receiver_destroy(&controller->receiver);
         return false;
     }
 
     if (!(controller->event_cond = SDL_CreateCond())) {
+        receiver_destroy(&controller->receiver);
         SDL_DestroyMutex(controller->mutex);
         return false;
     }
@@ -34,6 +40,8 @@ controller_destroy(struct controller *controller) {
     while (cbuf_take(&controller->queue, &event)) {
         control_event_destroy(&event);
     }
+
+    receiver_destroy(&controller->receiver);
 }
 
 bool
@@ -101,6 +109,12 @@ controller_start(struct controller *controller) {
         return false;
     }
 
+    if (!receiver_start(&controller->receiver)) {
+        controller_stop(controller);
+        SDL_WaitThread(controller->thread, NULL);
+        return false;
+    }
+
     return true;
 }
 
@@ -115,4 +129,5 @@ controller_stop(struct controller *controller) {
 void
 controller_join(struct controller *controller) {
     SDL_WaitThread(controller->thread, NULL);
+    receiver_join(&controller->receiver);
 }

app/src/controller.h

@@ -8,6 +8,7 @@
 #include "cbuf.h"
 #include "control_event.h"
 #include "net.h"
+#include "receiver.h"
 
 struct control_event_queue CBUF(struct control_event, 64);
 
@@ -18,6 +19,7 @@ struct controller {
     SDL_cond *event_cond;
     bool stopped;
     struct control_event_queue queue;
+    struct receiver receiver;
 };
 
 bool

app/src/receiver.c

@@ -0,0 +1,108 @@
+#include "receiver.h"
+
+#include <SDL2/SDL_assert.h>
+#include <SDL2/SDL_clipboard.h>
+
+#include "config.h"
+#include "device_event.h"
+#include "events.h"
+#include "lock_util.h"
+#include "log.h"
+
+bool
+receiver_init(struct receiver *receiver, socket_t control_socket) {
+    if (!(receiver->mutex = SDL_CreateMutex())) {
+        return false;
+    }
+    receiver->control_socket = control_socket;
+    return true;
+}
+
+void
+receiver_destroy(struct receiver *receiver) {
+    SDL_DestroyMutex(receiver->mutex);
+}
+
+static void
+process_event(struct receiver *receiver, struct device_event *event) {
+    switch (event->type) {
+        case DEVICE_EVENT_TYPE_GET_CLIPBOARD:
+            SDL_SetClipboardText(event->clipboard_event.text);
+            break;
+    }
+}
+
+static ssize_t
+process_events(struct receiver *receiver, const unsigned char *buf,
+               size_t len) {
+    size_t head = 0;
+    for (;;) {
+        struct device_event event;
+        ssize_t r = device_event_deserialize(&buf[head], len - head, &event);
+        if (r == -1) {
+            return -1;
+        }
+        if (r == 0) {
+            return head;
+        }
+
+        process_event(receiver, &event);
+        device_event_destroy(&event);
+
+        head += r;
+        SDL_assert(head <= len);
+        if (head == len) {
+            return head;
+        }
+    }
+}
+
+static int
+run_receiver(void *data) {
+    struct receiver *receiver = data;
+
+    unsigned char buf[DEVICE_EVENT_SERIALIZED_MAX_SIZE];
+    size_t head = 0;
+
+    for (;;) {
+        SDL_assert(head < DEVICE_EVENT_SERIALIZED_MAX_SIZE);
+        ssize_t r = net_recv(receiver->control_socket, buf,
+                             DEVICE_EVENT_SERIALIZED_MAX_SIZE - head);
+        if (r <= 0) {
+            LOGD("Receiver stopped");
+            break;
+        }
+
+        ssize_t consumed = process_events(receiver, buf, r);
+        if (consumed == -1) {
+            // an error occurred
+            break;
+        }
+
+        if (consumed) {
+            // shift the remaining data in the buffer
+            memmove(buf, &buf[consumed], r - consumed);
+            head = r - consumed;
+        }
+    }
+
+    return 0;
+}
+
+bool
+receiver_start(struct receiver *receiver) {
+    LOGD("Starting receiver thread");
+
+    receiver->thread = SDL_CreateThread(run_receiver, "receiver", receiver);
+    if (!receiver->thread) {
+        LOGC("Could not start receiver thread");
+        return false;
+    }
+
+    return true;
+}
+
+void
+receiver_join(struct receiver *receiver) {
+    SDL_WaitThread(receiver->thread, NULL);
+}

app/src/receiver.h

@@ -0,0 +1,32 @@
+#ifndef RECEIVER_H
+#define RECEIVER_H
+
+#include <stdbool.h>
+#include <SDL2/SDL_mutex.h>
+#include <SDL2/SDL_thread.h>
+
+#include "net.h"
+
+// receive events from the device
+// managed by the controller
+struct receiver {
+    socket_t control_socket;
+    SDL_Thread *thread;
+    SDL_mutex *mutex;
+};
+
+bool
+receiver_init(struct receiver *receiver, socket_t control_socket);
+
+void
+receiver_destroy(struct receiver *receiver);
+
+bool
+receiver_start(struct receiver *receiver);
+
+// no receiver_stop(), it will automatically stop on control_socket shutdown
+
+void
+receiver_join(struct receiver *receiver);
+
+#endif