Extract server-related functions

To lighten screen.c, move start_server() and stop_server() to a separate
file.

app/meson.build

@@ -11,6 +11,7 @@ src = [
     'src/lockutil.c',
     'src/netutil.c',
     'src/screen.c',
+    'src/server.c',
     'src/strutil.c',
 ]
 

app/src/screen.c

@@ -16,6 +16,7 @@
 #include "frames.h"
 #include "lockutil.h"
 #include "netutil.h"
+#include "server.h"
 
 #define DEVICE_NAME_FIELD_LENGTH 64
 #define SOCKET_NAME "scrcpy"
@@ -65,23 +66,6 @@ static TCPsocket listen_on_port(Uint16 port) {
     return SDLNet_TCP_Open(&addr);
 }
 
-static process_t start_server(const char *serial) {
-    const char *const cmd[] = {
-        "shell",
-        "CLASSPATH=/data/local/tmp/scrcpy-server.jar",
-        "app_process",
-        "/system/bin",
-        "com.genymobile.scrcpy.ScrCpyServer"
-    };
-    return adb_execute(serial, cmd, sizeof(cmd) / sizeof(cmd[0]));
-}
-
-static void stop_server(process_t server) {
-    if (!cmd_terminate(server)) {
-        SDL_LogError(SDL_LOG_CATEGORY_SYSTEM, "Could not kill: %s", strerror(errno));
-    }
-}
-
 // name must be at least DEVICE_NAME_FIELD_LENGTH bytes
 SDL_bool read_initial_device_info(TCPsocket socket, char *device_name, struct size *size) {
     unsigned char buf[DEVICE_NAME_FIELD_LENGTH + 4];

app/src/server.c

@@ -0,0 +1,21 @@
+#include "command.h"
+
+#include <SDL2/SDL_log.h>
+#include <errno.h>
+
+process_t start_server(const char *serial) {
+    const char *const cmd[] = {
+        "shell",
+        "CLASSPATH=/data/local/tmp/scrcpy-server.jar",
+        "app_process",
+        "/system/bin",
+        "com.genymobile.scrcpy.ScrCpyServer"
+    };
+    return adb_execute(serial, cmd, sizeof(cmd) / sizeof(cmd[0]));
+}
+
+void stop_server(process_t server) {
+    if (!cmd_terminate(server)) {
+        SDL_LogError(SDL_LOG_CATEGORY_SYSTEM, "Could not terminate server: %s", strerror(errno));
+    }
+}

app/src/server.h

@@ -0,0 +1,4 @@
+#include "command.h"
+
+process_t start_server(const char *serial);
+void stop_server(process_t server);