refactor(libacron/acronc/helloworld): move to separate directories

The corresponding CMakeLists.txt files are still rough.

21 files changed, 1 insertions, 1682 deletions

diff --git a/client/libacron/CMakeLists.txt b/client/libacron/CMakeLists.txt
index 57ce521..57da4af 100644
--- a/client/libacron/CMakeLists.txt
+++ b/client/libacron/CMakeLists.txt
@@ -89,32 +89,7 @@ target_link_libraries(ac ${LIBAC_DEPS})
 target_include_directories(ac-static PUBLIC ${LIBAC_INCLUDES})
 target_link_libraries(ac-static ${LIBAC_DEPS})
 
-# Apps
-if(WIN32)
-    set(APPS_DEPS ws2_32)
-endif()
-set(APPS_DEPS ${APPS_DEPS} ac)
-
-# apps/helloworld
-add_executable(helloworld
-        apps/helloworld/main.c
-        apps/helloworld/net.c
-        apps/helloworld/net.h
-        )
-target_link_libraries(helloworld ${APPS_DEPS})
-target_include_directories(helloworld PUBLIC "${PROJECT_BINARY_DIR}" include/)
-
-# apps/acronc
-add_executable(acronc
-        apps/acronc/main.c
-        apps/acronc/common.h
-        apps/acronc/log.h
-        apps/acronc/log.c
-        apps/acronc/handler.h apps/acronc/handler_signal.c apps/acronc/config.c apps/acronc/config.h apps/acronc/client.c apps/acronc/client.h apps/acronc/handler_stdin.c apps/acronc/helpers.c apps/acronc/helpers.h apps/acronc/handler_socket.c apps/acronc/async_dns.c)
-target_link_libraries(acronc ${APPS_DEPS} uv)
-target_include_directories(acronc PUBLIC "${PROJECT_BINARY_DIR}" include/)
-
-install(TARGETS ac ac-static helloworld acronc
+install(TARGETS ac ac-static
     EXPORT ${PROJECT_NAME}-targets
     RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
diff --git a/client/libacron/README.md b/client/libacron/README.md
index 418e07b..4514e21 100644
--- a/client/libacron/README.md
+++ b/client/libacron/README.md
@@ -3,9 +3,6 @@
 A client library written in C, 
 based on [json-c](https://github.com/json-c/json-c) and [wic](https://github.com/cjhdev/wic).
 
-This document is for client developers. For users who want a remote console to their Minecraft
-server, they should consult [acronc(1)](apps/acronc), a ready-to-use Acron cli.
-
 ## Building
 
 Requirements:
diff --git a/client/libacron/apps/acronc/README.md b/client/libacron/apps/acronc/README.md
deleted file mode 100644
index 87c9db0..0000000
--- a/client/libacron/apps/acronc/README.md
+++ /dev/null
@@ -1,11 +0,0 @@
-# acronc(1)
-
-Acron client using libac and libuv, written in C.
-
-Current status: In development.
-
-Windows is currently not supported yet.
-
-## License
-
-GPL-2.0-only
\ No newline at end of file
diff --git a/client/libacron/apps/acronc/async_dns.c b/client/libacron/apps/acronc/async_dns.c
deleted file mode 100644
index 2e221cf..0000000
--- a/client/libacron/apps/acronc/async_dns.c
+++ /dev/null
@@ -1,65 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "handler.h"
-#include "log.h"
-
-#include <uv.h>
-
-static uv_getaddrinfo_t resolv;
-
-static struct addrinfo *ai = NULL;
-static struct addrinfo *ai_current = NULL;
-static void (*cb)(int status,
-           const struct addrinfo *,
-           void (*on_connect_result)(bool)) = NULL;
-
-static void on_conn(bool res) {
-    if (res) {
-        uv_freeaddrinfo(ai);
-        ai = NULL;
-        ai_current = NULL;
-        cb = NULL;
-        return;
-    }
-    ai_current = ai_current->ai_next;
-    if (!ai_current) {
-        /* No more result available. */
-        cb(1, NULL, NULL);
-        uv_freeaddrinfo(ai);
-        ai = NULL;
-        ai_current = NULL;
-        cb = NULL;
-        return;
-    }
-    cb(0, ai_current, &on_conn);
-}
-
-static void on_resolv(uv_getaddrinfo_t *req, int status, struct addrinfo *res) {
-    LOGDV("on_resolv(req = %p): status = %d, res = %p",
-          req,
-          status,
-          res);
-    if (status) {
-        LOGEV("Cannot resolve host: %s", uv_strerror(status));
-        cb(status, NULL, NULL);
-        return;
-    }
-    ai = res;
-    ai_current = res;
-    cb(0, ai_current, &on_conn);
-}
-
-int a_dns(const char *host,
-          uint16_t port,
-          void (*c)(int status,
-                  const struct addrinfo *,
-                  void (*on_connect_result)(bool))) {
-    int r;
-    char service[6];
-    snprintf(service, 6, "%u", port);
-    cb = c;
-    if ((r = uv_getaddrinfo(loop, &resolv, on_resolv, host, service, NULL))) return r;
-    return 0;
-}
diff --git a/client/libacron/apps/acronc/client.c b/client/libacron/apps/acronc/client.c
deleted file mode 100644
index 5553d4c..0000000
--- a/client/libacron/apps/acronc/client.c
+++ /dev/null
@@ -1,114 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "client.h"
-#include "helpers.h"
-
-#include <libac.h>
-#include <stdio.h>
-
-static void handle_event(const ac_event_t *event) {
-    switch (event->type) {
-        case AC_EVENT_LAGGING: {
-            ac_event_lagging_t *o = (ac_event_lagging_t *) event;
-            printf("Server lagging: running %ld milliseconds (%ld ticks) behind.\n",
-                   o->ms,
-                   o->ticks);
-            break;
-        }
-        case AC_EVENT_ENTITY_DEATH: {
-            ac_event_entity_death_t *o = (ac_event_entity_death_t *) event;
-            printf("Entity '%s' died at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->entity.name,
-                   world_name(o->entity.world),
-                   o->entity.pos.x,
-                   o->entity.pos.y,
-                   o->entity.pos.z,
-                   o->message);
-            break;
-        }
-        case AC_EVENT_PLAYER_MESSAGE: {
-            ac_event_player_message_t *o = (ac_event_player_message_t *) event;
-            printf("Player '%s' said at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z,
-                   o->text);
-            break;
-        }
-        case AC_EVENT_PLAYER_DISCONNECT: {
-            ac_event_player_disconnect_t *o = (ac_event_player_disconnect_t *) event;
-            printf("Player '%s' disconnected at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z,
-                   o->reason);
-            break;
-        }
-        case AC_EVENT_PLAYER_JOIN: {
-            ac_event_player_join_t *o = (ac_event_player_join_t *) event;
-            printf("Player '%s' joined at %s(%.2f, %.2f, %.2f).\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z);
-            break;
-        }
-        default: {
-            printf("Received an unrecognized event of type '%u'.\n",
-                   event->type);
-        }
-    }
-}
-
-static void handle_response(const ac_response_t *response) {
-    switch (response->type) {
-        case AC_RESPONSE_OK: {
-            ac_response_ok_t *o = (ac_response_ok_t *) response;
-            printf("Request %d OK.\n",
-                   o->id);
-            break;
-        }
-        case AC_RESPONSE_ERROR: {
-            ac_response_error_t *o = (ac_response_error_t *) response;
-            printf("Request %d failed: %s (%d).\n",
-                   o->id,
-                   o->message,
-                   o->code);
-            break;
-        }
-        case AC_RESPONSE_CMD_OUT: {
-            ac_response_cmd_out_t *o = (ac_response_cmd_out_t *) response;
-            printf("Request %d output by %s: %s.\n",
-                   o->id,
-                   o->sender,
-                   o->out);
-            break;
-        }
-        case AC_RESPONSE_CMD_RESULT: {
-            ac_response_cmd_result_t *o = (ac_response_cmd_result_t *) response;
-            printf("Request %d is done: %s (%d).\n",
-                   o->id,
-                   o->success ? "Success" : "Failed",
-                   o->result);
-            break;
-        }
-        default: {
-            printf("Received an unrecognized response of type '%u'.\n",
-                   response->type);
-        }
-    }
-}
-
-int handle_object(ac_obj_t *obj) {
-    if (AC_IS_RESPONSE(obj->type)) handle_response((ac_response_t *) obj);
-    else handle_event((ac_event_t *) obj);
-    ac_object_free(obj);
-    return 0;
-}
\ No newline at end of file
diff --git a/client/libacron/apps/acronc/client.h b/client/libacron/apps/acronc/client.h
deleted file mode 100644
index 438d7fd..0000000
--- a/client/libacron/apps/acronc/client.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#ifndef ACRONC_CLIENT_H
-#define ACRONC_CLIENT_H
-
-#include <libac.h>
-
-int handle_object(ac_obj_t *obj);
-
-#endif /* ACRONC_CLIENT_H */
diff --git a/client/libacron/apps/acronc/common.h b/client/libacron/apps/acronc/common.h
deleted file mode 100644
index 0ca3b92..0000000
--- a/client/libacron/apps/acronc/common.h
+++ /dev/null
@@ -1,8 +0,0 @@
-/*
- * Created by yuuta on 7/23/22.
- */
-
-#ifndef ACRONC_COMMON_H
-#define ACRONC_COMMON_H
-
-#endif /* ACRONC_COMMON_H */
diff --git a/client/libacron/apps/acronc/config.c b/client/libacron/apps/acronc/config.c
deleted file mode 100644
index 046d931..0000000
--- a/client/libacron/apps/acronc/config.c
+++ /dev/null
@@ -1,100 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "config.h"
-
-#include <libac.h>
-#include <stdio.h>
-#include <errno.h>
-#include <string.h>
-#include <stdlib.h>
-
-int config_parse(const int argc, const char **argv, ac_connection_parameters_t *params) {
-    if (argc <= 1) {
-        fprintf(stderr, "Usage: %s [-t token] [-p port] <ID>@<server>\n"
-                        "Please refer to acronc(1) for more details.\n",
-                argv[0] ? "acronc" : argv[0]);
-        return 64;
-    }
-    bool svr_set = false;
-    for (int i = 1; i < argc; i++) {
-        const char *arg = argv[i];
-        if (arg[0] != '-') {
-            if (svr_set) {
-                fprintf(stderr, "Unexpected value: %s\n", arg);
-                return 64;
-            }
-            const char *id = strtok((char *) arg, "@");
-            if (!id) {
-                fprintf(stderr, "Malformed argument: should be ID@server.\n");
-                return 64;
-            }
-            const char *server = strtok(NULL, "");
-            if (!server) {
-                fprintf(stderr, "Malformed argument: should be ID@server.\n");
-                return 64;
-            }
-            params->host = (char *) server;
-            params->id = (char *) id;
-            svr_set = true;
-            continue;
-        }
-        char a = arg[1];
-        char **value_ptr;
-        char *port_str = NULL;
-        switch (a) {
-            case 't': {
-                value_ptr = &params->token;
-                goto read_value;
-            }
-            case 'p': {
-                value_ptr = &port_str;
-                goto read_value;
-            }
-            default: {
-                fprintf(stderr, "Unexpected switch -%c.\n", a);
-                return 64;
-            }
-        }
-        read_value:
-        {
-            if (i == (argc - 1)) {
-                fprintf(stderr, "-%c requires an argument.\n", a);
-                return 64;
-            }
-            *value_ptr = (char *) argv[++i];
-        }
-        if (port_str) {
-            errno = 0;
-            char *endptr;
-            unsigned long val = strtol(port_str, &endptr, 0);
-            if (errno) {
-                const int e = errno;
-                fprintf(stderr, "Cannot parse port: %s", strerror(e));
-                return e;
-            }
-            if (endptr == port_str) {
-                fprintf(stderr, "Illegal port.\n");
-                return 64;
-            }
-            if (val > UINT16_MAX) {
-                fprintf(stderr, "Illegal port.\n");
-                return 64;
-            }
-            params->port = (uint16_t) val;
-            port_str = NULL;
-        }
-    }
-    if (!params->host || !params->id) {
-        fprintf(stderr, "Usage: acronc ID@server[:port]\n");
-        return 64;
-    }
-    char tok[1024];
-    if (!params->token) {
-        printf("Token: ");
-        scanf("%1023[^\n]", tok);
-        params->token = tok;
-    }
-    return 0;
-}
\ No newline at end of file
diff --git a/client/libacron/apps/acronc/config.h b/client/libacron/apps/acronc/config.h
deleted file mode 100644
index ee51f34..0000000
--- a/client/libacron/apps/acronc/config.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#ifndef ACRONC_CONFIG_H
-#define ACRONC_CONFIG_H
-
-#include <libac.h>
-
-int config_parse(int argc, const char **argv, ac_connection_parameters_t *params);
-
-#endif /* ACRONC_CONFIG_H */
diff --git a/client/libacron/apps/acronc/handler.h b/client/libacron/apps/acronc/handler.h
deleted file mode 100644
index 1a2ccfe..0000000
--- a/client/libacron/apps/acronc/handler.h
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#ifndef ACRONC_HANDLER_H
-#define ACRONC_HANDLER_H
-
-#include <uv.h>
-#include <libac.h>
-
-enum exit_reason {
-    /* Exit due to a signal. Socket is working. */
-    EXIT_SIGNAL,
-    /* Exit due to an EOF from stdin. Socket is working. */
-    EXIT_STDIN_EOF,
-    /* Exit due to an EOF from socket. Socket is closed. */
-    EXIT_SOCKET_EOF,
-    /* Exit due to a socket failure. Socket is closed. */
-    EXIT_FAILURE_SOCKET,
-    /* Exit due to a failure. Socket is working. */
-    EXIT_FAILURE
-};
-
-struct uv_obj {
-    void *obj;
-    bool running;
-};
-
-extern uv_loop_t *loop;
-
-extern void (*on_exit)(enum exit_reason reason);
-
-int h_signal(void);
-
-int h_stdin(int (*on_input)(ac_request_t *req),
-            void (*on_close)(void));
-
-int h_socket(ac_connection_parameters_t *p,
-             const struct addrinfo *ai,
-             void (*on_connect_result)(bool),
-             int (*on_ready)(void),
-             int (*on_received)(ac_obj_t *obj),
-             void (*on_closed)(void));
-
-int sock_request(ac_request_t *req);
-
-int sock_ext(bool trigger_callback);
-
-int a_dns(const char *host,
-          uint16_t port,
-          void (*on_resolv)(int status,
-                            const struct addrinfo *,
-                            void (*on_connect_result)(bool)));
-
-#endif /* ACRONC_HANDLER_H */
diff --git a/client/libacron/apps/acronc/handler_signal.c b/client/libacron/apps/acronc/handler_signal.c
deleted file mode 100644
index 1d0ba7e..0000000
--- a/client/libacron/apps/acronc/handler_signal.c
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "handler.h"
-#include "log.h"
-
-static uv_signal_t sigint;
-static struct uv_obj obj_sigint = {
-        .obj = &sigint,
-        .running = false
-};
-static uv_signal_t sigterm;
-static struct uv_obj obj_sigterm = {
-        .obj = &sigterm,
-        .running = false
-};
-
-static void on_signal(uv_signal_t *handle, int signum) {
-    LOGDV("on_signal(handle = %p): %d",
-          handle,
-          signum);
-    uv_signal_stop(&sigint);
-    obj_sigint.running = false;
-    uv_signal_stop(&sigterm);
-    obj_sigterm.running = false;
-    on_exit(EXIT_SIGNAL);
-}
-
-int h_signal(void) {
-    int r;
-    if ((r = uv_signal_init(loop, &sigint))) return r;
-    if ((r = uv_signal_start(&sigint, on_signal, SIGINT))) return r;
-
-    obj_sigint.running = true;
-    if ((r = uv_signal_init(loop, &sigterm))) return r;
-    if ((r = uv_signal_start(&sigterm, on_signal, SIGTERM))) return r;
-    obj_sigterm.running = true;
-    return 0;
-}
diff --git a/client/libacron/apps/acronc/handler_socket.c b/client/libacron/apps/acronc/handler_socket.c
deleted file mode 100644
index ff8eefb..0000000
--- a/client/libacron/apps/acronc/handler_socket.c
+++ /dev/null
@@ -1,255 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "handler.h"
-#include "log.h"
-#include "helpers.h"
-
-#include <uv.h>
-#include <stdlib.h>
-#include <string.h>
-
-static void (*cb_conn)(bool);
-
-static int (*cb_ready)(void);
-
-static int (*cb_recv)(ac_obj_t *obj);
-
-static void (*cb_close)(void);
-
-static ac_connection_parameters_t *params;
-
-static uv_tcp_t sock;
-static uv_write_t write;
-
-static uv_connect_t conn;
-
-static bool ready = false;
-static void *ac_conn = NULL;
-
-#define RUNNING !uv_is_closing((uv_handle_t *) &sock)
-
-static void on_close(uv_handle_t *handle) {
-    LOGDV("on_close(handle = %p)",
-          handle);
-    if (handle->data)
-        cb_close();
-}
-
-static void ex2(bool force, bool cb) {
-    LOGDV("Exiting socket handlers: Force WebSocket close: %s; Socket still running: %s.",
-          force ? "true" : "false",
-          RUNNING ? "true" : "false");
-    if (ac_conn) {
-        ac_disconnect(ac_conn,
-                      RUNNING ? force : true /* If sock is not running, always force */);
-        ac_conn = NULL;
-    }
-    if (RUNNING) {
-        sock.data = cb ? &ex2 /* Any non-NULL value */ : NULL;
-        uv_close((uv_handle_t *) &sock, on_close);
-    } else {
-        if (cb) {
-            cb_close();
-        }
-    }
-}
-
-static void ex(bool force) {
-    ex2(force, true);
-}
-
-int sock_ext(bool trigger_callback) {
-    ex2(false, trigger_callback);
-    return 0;
-}
-
-static void on_alloc(uv_handle_t *handle, size_t size, uv_buf_t *buf) {
-    LOGDV("on_alloc(handle = %p): size = %lu",
-          handle,
-          size);
-    void *b = malloc(size);
-    if (!b) {
-        LOGEV("Cannot allocate memory of %u bytes: %s.",
-              size,
-              strerror(errno));
-        /* Socket is still working now. */
-        ex(false);
-        *buf = uv_buf_init(NULL, 0); /* Just in case? */
-        return;
-    }
-    *buf = uv_buf_init(b, size);
-}
-
-static void on_read(uv_stream_t *tcp, ssize_t nread, const uv_buf_t *buf) {
-    LOGDV("on_read(stream = %p): nread = %ld, buf = %p, buf->base = %p, buf->len = %lu",
-          tcp,
-          nread,
-          buf, buf->base, buf->len);
-    if (!nread) {
-        /* EAGAIN */
-        if (buf->base) free(buf->base);
-        return;
-    }
-    if (nread == UV_EOF) {
-        LOGW("Received EOF from server.");
-        free(buf->base);
-        /* The socket * should * be closed already? */
-        ex(true);
-        return;
-    }
-    if (nread < 0) {
-        LOGEV("Encountered a failure while reading from the socket: ", uv_strerror(nread));
-        if (buf->base) free(buf->base);
-        /* Docs: The callee is responsible for stopping/closing the stream when an error happens */
-        ex(true); /* Force close libac connection here. */
-        return;
-    }
-    int r;
-    ac_obj_t *obj = NULL;
-    if ((r = ac_receive(ac_conn, buf->base, nread, &obj))) {
-        LOGEV("Cannot parse the response (%d).", r);
-        /* libac error. Socket is working. */
-        ex(false);
-        return;
-    }
-
-    if (!ready) {
-        enum ac_connection_state state;
-        if ((r = ac_get_state(ac_conn, &state))) {
-            LOGEV("Cannot get state (%d).", r);
-            /* libac error. Socket is working. */
-            ex(false);
-            return;
-        }
-        if (state == AC_STATE_READY) {
-            ready = true;
-            if ((cb_ready())) {
-                /* acronc error. Socket is working. */
-                ex(false);
-                return;
-            }
-        }
-    }
-    if (obj) {
-        LOGDV("Got object: %p", obj);
-        /* uv_async_send is unreliable, and missed messages will cause memory leak. */
-        if (cb_recv(obj)) {
-            /* acronc error. Socket is working. */
-            ex(false);
-        }
-    }
-
-    free(buf->base);
-}
-
-static void on_write(uv_write_t *req, int status) {
-    LOGDV("on_write(req = %p): %d",
-          req,
-          status);
-    if (status) {
-        LOGEV("Cannot write to socket: %s", uv_strerror(status));
-        /* Socket may be closed? Anyway writing again will definitely be problematic, but closing may not. */
-        ex(true);
-    }
-}
-
-static int on_send(const void *s,
-                   const void *buf,
-                   const size_t len) {
-    LOGDV("on_send(s = %p): len = %u",
-          s,
-          len);
-    const uv_stream_t *stream = s;
-    uv_buf_t buffer[] = {
-            {.base = (char *) buf, .len = len}
-    };
-    int r;
-    if ((r = uv_write(&write, (uv_stream_t *) stream, buffer, 1, on_write))) {
-        LOGEV("Cannot write to socket: %s", uv_strerror(r));
-        /* Socket may be closed? Anyway writing again will definitely be problematic, but closing may not. */
-        ex(true);
-    }
-    return 0;
-}
-
-static void on_retry_closed(uv_handle_t *handle) {
-    cb_conn(false);
-}
-
-static void on_connect(uv_connect_t *req, int status) {
-    LOGDV("on_connect(req = %p): status = %d",
-          req,
-          status);
-    if (status) {
-        LOGEV("Cannot connect to the server: %s", uv_strerror(status));
-        /* Close it for the next retry. */
-        if (RUNNING) {
-            LOGD("Closing socket before retry.");
-            uv_close((uv_handle_t *) &sock, on_retry_closed);
-        } else {
-            cb_conn(false);
-        }
-        return;
-    }
-    LOGI("Connected.");
-    uv_stream_t *stream = req->handle;
-    int r;
-    params->sock = stream;
-    if ((r = ac_connect(*params, &ac_conn))) {
-        LOGEV("Cannot initialize connection: %d.", r);
-        cb_conn(false);
-        return;
-    }
-    if ((r = uv_read_start(stream, on_alloc, on_read))) {
-        LOGEV("Cannot read socket: %s", uv_strerror(r));
-        cb_conn(false);
-        return;
-    }
-    cb_conn(true);
-}
-
-int h_socket(ac_connection_parameters_t *p,
-             const struct addrinfo *ai,
-             void (*on_connect_result)(bool),
-             int (*on_ready)(void),
-             int (*on_received)(ac_obj_t *obj),
-             void (*on_closed)(void)) {
-    cb_conn = on_connect_result;
-    cb_ready = on_ready;
-    cb_recv = on_received;
-    cb_close = on_closed;
-    params = p;
-    params->on_send = on_send;
-
-    struct sockaddr *sa = ai->ai_addr;
-    LOGIV("Connecting to %s...", ntop(sa));
-    int r;
-    if ((r = uv_tcp_init(loop, &sock))) {
-        LOGEV("Cannot initialize the socket: %s", uv_strerror(r));
-        return r;
-    }
-    if ((r = uv_tcp_connect(&conn, &sock, sa, on_connect))) {
-        LOGEV("Cannot initialize the connection: %s", uv_strerror(r));
-        return r;
-    }
-    return 0;
-}
-
-int sock_request(ac_request_t *req) {
-    if (!ac_conn) {
-        /* Just in case. */
-        LOGE("sock_request() called on a closed socket.");
-        /* Ignore it. */
-        return 0;
-    }
-    int r = ac_request(ac_conn, req);
-    if (r) {
-        LOGEV("Cannot send request: %d.", r);
-        /* libac error. Socket is working. */
-        ex(false);
-    }
-    return r;
-}
-
diff --git a/client/libacron/apps/acronc/handler_stdin.c b/client/libacron/apps/acronc/handler_stdin.c
deleted file mode 100644
index 3ac307d..0000000
--- a/client/libacron/apps/acronc/handler_stdin.c
+++ /dev/null
@@ -1,85 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "handler.h"
-#include "log.h"
-
-#include <stdlib.h>
-#include <string.h>
-
-static unsigned int id = 0;
-
-static uv_tty_t tty;
-
-static int (*cb_recv)(ac_request_t *req);
-
-static void (*cb_close)(void);
-
-static void on_close(uv_handle_t *handle) {
-    cb_close();
-}
-
-static void on_alloc(uv_handle_t *handle, size_t size, uv_buf_t *buf) {
-    LOGDV("on_alloc(handle = %p): size = %lu",
-          handle,
-          size);
-    void *b = malloc(size);
-    if (!b) {
-        LOGEV("Cannot allocate memory of %u bytes: %s.",
-              size,
-              strerror(errno));
-        /* Stream is still working now. */
-        uv_close(handle, on_close);
-        *buf = uv_buf_init(NULL, 0); /* Just in case? */
-        return;
-    }
-    *buf = uv_buf_init(b, size);
-}
-
-static void on_stdin(uv_stream_t *t, ssize_t nread, const uv_buf_t *buf) {
-    LOGDV("on_stdin(stream = %p): nread = %ld, buf = %p, buf->base = %p, buf->len = %lu",
-          t,
-          nread,
-          buf, buf->base, buf->len);
-    if (!nread) {
-        if (buf->base) free(buf->base);
-        return;
-    }
-    if (nread == UV_EOF) {
-        LOGI("Exit.");
-        free(buf->base);
-
-        cb_close();
-        return;
-    }
-    if (nread < 0) {
-        LOGEV("Encountered a failure while reading stdin: ", uv_strerror(nread));
-        if (buf->base) free(buf->base);
-        uv_close((uv_handle_t *) t, on_close);
-        return;
-    }
-    buf->base[nread - 1] = '\0'; /* Remove junk and tailing \n */
-    if ((++ id) > INT_MAX) {
-        id = 0;
-    }
-    ac_request_cmd_t req = {
-            .type = AC_REQUEST_CMD,
-            .id = (int) id,
-            .cmd = buf->base
-    };
-    if (cb_recv((ac_request_t *) &req)) {
-        uv_close((uv_handle_t *) t, on_close);
-    }
-    free(buf->base);
-}
-
-int h_stdin(int (*on_input)(ac_request_t *req),
-            void (*on_close)(void)) {
-    cb_recv = on_input;
-    cb_close = on_close;
-    int r;
-    if ((r = uv_tty_init(loop, &tty, 0, 0))) return r;
-    if ((r = uv_read_start((uv_stream_t *) &tty, on_alloc, on_stdin))) return r;
-    return 0;
-}
\ No newline at end of file
diff --git a/client/libacron/apps/acronc/helpers.c b/client/libacron/apps/acronc/helpers.c
deleted file mode 100644
index 9e141d4..0000000
--- a/client/libacron/apps/acronc/helpers.c
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#include "helpers.h"
-
-#include <libac.h>
-#include <string.h>
-#include <errno.h>
-
-#ifdef WIN32
-#include <winsock2.h>
-#include <ws2tcpip.h>
-#include <ws2ipdef.h>
-
-#define errno_sock WSAGetLastError()
-
-#else
-
-#include <arpa/inet.h>
-#include <sys/socket.h>
-
-#define errno_sock errno
-
-#endif
-
-const char *ntop(const struct sockaddr *sa) {
-    static char buf[INET6_ADDRSTRLEN];
-    const char *retval;
-    switch (sa->sa_family) {
-        case AF_INET: {
-            retval = inet_ntop(AF_INET, &((struct sockaddr_in *) sa)->sin_addr, buf, sizeof(buf));
-            break;
-        }
-        case AF_INET6: {
-            retval = inet_ntop(AF_INET6, &((struct sockaddr_in6 *) sa)->sin6_addr, buf, sizeof(buf));
-            break;
-        }
-        default: {
-            return "Unknown address family";
-        }
-    }
-    if (retval) return retval;
-    return strerror(errno_sock);
-}
-
-const char *world_name(const enum ac_world world) {
-    switch (world) {
-        case overworld:
-            return "overworld";
-        case nether:
-            return "nether";
-        case end:
-            return "end";
-        default:
-            return "unknown world";
-    }
-}
diff --git a/client/libacron/apps/acronc/helpers.h b/client/libacron/apps/acronc/helpers.h
deleted file mode 100644
index e983439..0000000
--- a/client/libacron/apps/acronc/helpers.h
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * Created by yuuta on 7/24/22.
- */
-
-#ifndef ACRONC_HELPERS_H
-#define ACRONC_HELPERS_H
-
-#include <libac.h>
-
-#ifdef WIN32
-#include <winsock2.h>
-#include <ws2tcpip.h>
-
-#else
-
-#include <sys/socket.h>
-
-#endif
-
-const char *ntop(const struct sockaddr *sa);
-
-const char *world_name(enum ac_world world);
-
-#endif /* ACRONC_HELPERS_H */
diff --git a/client/libacron/apps/acronc/log.c b/client/libacron/apps/acronc/log.c
deleted file mode 100644
index 08f48b6..0000000
--- a/client/libacron/apps/acronc/log.c
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * Created by yuuta on 1/1/22.
- */
-
-#define _GNU_SOURCE
-
-#include "log.h"
-#include "config.h"
-
-#include <stdio.h>
-#include <stdarg.h>
-#include <assert.h>
-
-#ifdef __linux__
-#include <sys/types.h>
-#include <unistd.h>
-#include <sys/syscall.h>
-#endif
-
-void g_log(enum log_level level,
-                  const char *file,
-                  int line,
-                  const char *format,
-                  ...) {
-    FILE *stream = stderr;
-    switch (level) {
-        case log_fetal:
-            fprintf(stream, "F");
-            break;
-        case log_error:
-            fprintf(stream, "E");
-            break;
-        case log_warn:
-            fprintf(stream, "W");
-            break;
-        case log_info:
-            fprintf(stream, "I");
-            break;
-        case log_debug:
-#ifdef DEBUG
-            fprintf(stream, "D");
-            break;
-#else
-            return;
-#endif
-        default:
-            fprintf(stderr, "Unknown log level: %d.\n", level);
-            assert(0);
-    }
-    int tid = -1;
-#ifdef __linux__
-    tid = (int) syscall(__NR_gettid);
-#endif
-    fprintf(stream, "[%d %s:%d]: ",
-            tid, file, line);
-    va_list list;
-    va_start(list, format);
-    vfprintf(stream, format, list);
-    va_end(list);
-    fprintf(stream, "\n");
-}
diff --git a/client/libacron/apps/acronc/log.h b/client/libacron/apps/acronc/log.h
deleted file mode 100644
index 7bc9532..0000000
--- a/client/libacron/apps/acronc/log.h
+++ /dev/null
@@ -1,52 +0,0 @@
-/*
- * Created by yuuta on 1/1/22.
- */
-
-#ifndef LOG_H
-#define LOG_H
-
-enum log_level {
-    log_fetal = 1,
-    log_error = 2,
-    log_warn = 3,
-    log_info = 4,
-    log_debug = 5
-};
-
-void g_log(enum log_level level,
-           const char *file,
-           int line,
-           const char *format,
-           ...);
-
-#define LOGF(X) g_log(log_fetal, __FUNCTION__, __LINE__, X)
-
-#define LOGFV(X, ...) g_log(log_fetal, __FUNCTION__, __LINE__, X, __VA_ARGS__)
-
-#define LOGE(X) g_log(log_error, __FUNCTION__, __LINE__, X)
-
-#define LOGEV(X, ...) g_log(log_error, __FUNCTION__, __LINE__, X, __VA_ARGS__)
-
-#define LOGW(X) g_log(log_warn, __FUNCTION__, __LINE__, X)
-
-#define LOGWV(X, ...) g_log(log_warn, __FUNCTION__, __LINE__, X, __VA_ARGS__)
-
-#define LOGI(X) g_log(log_info, __FUNCTION__, __LINE__, X)
-
-#define LOGIV(X, ...) g_log(log_info, __FUNCTION__, __LINE__, X, __VA_ARGS__)
-
-#ifdef DEBUG
-
-#define LOGD(X) g_log(log_debug, __FUNCTION__, __LINE__, X)
-
-#define LOGDV(X, ...) g_log(log_debug, __FUNCTION__, __LINE__, X, __VA_ARGS__)
-
-#else
-
-#define LOGD(X)
-
-#define LOGDV(X, ...)
-
-#endif
-
-#endif /* LOG_H */
diff --git a/client/libacron/apps/acronc/main.c b/client/libacron/apps/acronc/main.c
deleted file mode 100644
index 6e18ed2..0000000
--- a/client/libacron/apps/acronc/main.c
+++ /dev/null
@@ -1,105 +0,0 @@
-/*
- * Created by yuuta on 7/23/22.
- */
-
-#include "log.h"
-#include "handler.h"
-#include "config.h"
-#include "helpers.h"
-#include "client.h"
-
-#include <libac.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <uv.h>
-#include <err.h>
-#include <string.h>
-
-static uv_loop_t lop;
-uv_loop_t *loop = &lop;
-
-static void on_close(uv_handle_t *handle);
-
-static ac_connection_parameters_t params = {
-        .sock = NULL,
-        .version = 0,
-        .port = 25575,
-        .host = NULL,
-        .id = NULL,
-        .token = NULL,
-        .on_send = NULL,
-};
-
-static void cleanup(void) {
-    LOGD("cleanup()");
-    /* sock must be closed before cleanup(). */
-    uv_loop_close(loop);
-    ac_free();
-    uv_tty_reset_mode();
-}
-
-static void on_stdin_closed(void) {
-    sock_ext(true);
-}
-
-static void on_sock_closed(void) {
-    uv_stop(loop);
-}
-
-static int on_input(ac_request_t *req) {
-    /* The socket will close itself upon errors. So do the input stream. */
-    return sock_request(req);
-}
-
-static int on_sock_ready(void) {
-    return h_stdin(on_input, on_stdin_closed);
-}
-
-static void on_resolv(int status, const struct addrinfo *ai, void (*on_connected)(bool)) {
-    if (status) {
-        uv_stop(loop);
-        return;
-    }
-
-    if (h_socket(&params,
-                      ai,
-                      on_connected,
-                      on_sock_ready,
-                      handle_object,
-                      on_sock_closed)) {
-        /* Mark as true to clean up resources and prevent next retry. */
-        on_connected(true);
-        uv_stop(loop);
-    }
-}
-
-int main(int argc, const char **argv) {
-    int r;
-
-    if ((r = config_parse(argc, argv, &params))) return r;
-    atexit(cleanup);
-    libac_config_t config = {
-#ifdef DEBUG
-            .out = NULL,
-#else
-            .out = NULL,
-#endif
-            .tok = NULL
-    };
-    if ((r = ac_init(&config))) errx(r, "Cannot initialize Acron library.");
-
-    if ((r = uv_loop_init(loop))) goto uviniterr;
-    if ((r = h_signal())) goto uviniterr;
-    if ((r = a_dns(params.host, params.port, on_resolv))) goto uviniterr;
-
-    if ((r = uv_run(loop, UV_RUN_DEFAULT))) {
-        if (r == 1) {
-            /* Seems to return 1 if uv_stop is called. */
-            return 0;
-        }
-        errx(-r, "Cannot run: %s", uv_strerror(r));
-    }
-    return 0;
-    uviniterr:
-    errx(-r, "Cannot initialize: %s", uv_strerror(r));
-}
\ No newline at end of file
diff --git a/client/libacron/apps/helloworld/main.c b/client/libacron/apps/helloworld/main.c
deleted file mode 100644
index c112fcb..0000000
--- a/client/libacron/apps/helloworld/main.c
+++ /dev/null
@@ -1,370 +0,0 @@
-/*
- * Created by yuuta on 7/20/22.
- */
-
-#include "libac.h"
-#include "net.h"
-
-#include <stdio.h>
-
-#ifndef WIN32
-
-#include <signal.h>
-#include <errno.h>
-#include <string.h>
-
-#endif
-
-#ifdef __STDC_NO_THREADS__
-# ifdef WIN32
-#define THREAD_WIN32
-#include <windows.h>
-static HANDLE mtx_conn;
-
-int lock(void) { \
-DWORD _dwlck = WaitForSingleObject(mtx_conn, 0); \
-if (_dwlck == WAIT_FAILED) { _dwlck = GetLastError(); } \
-if (_dwlck) { fprintf(stderr, "Cannot lock the mutex: %d.\n", _dwlck); return _dwlck; } \
-return 0; \
-}
-
-int unlock(void) { \
-if (!ReleaseMutex(mtx_conn)) { \
-int r = GetLastError();        \
-fprintf(stderr, "Cannot release the mutex: %d.\n", r); \
-return r;      \
-} \
-return 0;    \
-}
-
-# else
-#error "Either C11 threading or Win32 API is required for concurrency."
-# endif
-#else
-
-#define THREAD_C11
-
-#include <threads.h>
-
-static mtx_t mtx_conn;
-
-int lock(void) {
-    \
-if (mtx_lock(&mtx_conn) != thrd_success) {
-        \
-fprintf(stderr, "Cannot lock the mutex.\n"); \
-return 1;    \
-
-    }            \
-return 0;   \
-
-}
-
-int unlock(void) {
-    \
-if (mtx_unlock(&mtx_conn) != thrd_success) {
-        \
-fprintf(stderr, "Cannot release the mutex.\n"); \
-return 1;      \
-
-    }              \
-return 0; \
-
-}
-
-#endif
-
-static const char *world_name(const enum ac_world world) {
-    switch (world) {
-        case overworld:
-            return "overworld";
-        case nether:
-            return "nether";
-        case end:
-            return "end";
-        default:
-            return "unknown world";
-    }
-}
-
-static void handle_event(const ac_event_t *event) {
-    switch (event->type) {
-        case AC_EVENT_LAGGING: {
-            ac_event_lagging_t *o = (ac_event_lagging_t *) event;
-            printf("Server lagging: running %ld milliseconds (%ld ticks) behind.\n",
-                   o->ms,
-                   o->ticks);
-            break;
-        }
-        case AC_EVENT_ENTITY_DEATH: {
-            ac_event_entity_death_t *o = (ac_event_entity_death_t *) event;
-            printf("Entity '%s' died at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->entity.name,
-                   world_name(o->entity.world),
-                   o->entity.pos.x,
-                   o->entity.pos.y,
-                   o->entity.pos.z,
-                   o->message);
-            break;
-        }
-        case AC_EVENT_PLAYER_MESSAGE: {
-            ac_event_player_message_t *o = (ac_event_player_message_t *) event;
-            printf("Player '%s' said at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z,
-                   o->text);
-            break;
-        }
-        case AC_EVENT_PLAYER_DISCONNECT: {
-            ac_event_player_disconnect_t *o = (ac_event_player_disconnect_t *) event;
-            printf("Player '%s' disconnected at %s(%.2f, %.2f, %.2f): %s.\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z,
-                   o->reason);
-            break;
-        }
-        case AC_EVENT_PLAYER_JOIN: {
-            ac_event_player_join_t *o = (ac_event_player_join_t *) event;
-            printf("Player '%s' joined at %s(%.2f, %.2f, %.2f).\n",
-                   o->player.name,
-                   world_name(o->player.world),
-                   o->player.pos.x,
-                   o->player.pos.y,
-                   o->player.pos.z);
-            break;
-        }
-        default: {
-            printf("Received an unrecognized event of type '%u'.\n",
-                   event->type);
-        }
-    }
-}
-
-static void handle_response(const ac_response_t *response) {
-    switch (response->type) {
-        case AC_RESPONSE_OK: {
-            ac_response_ok_t *o = (ac_response_ok_t *) response;
-            printf("Request %d OK.\n",
-                   o->id);
-            break;
-        }
-        case AC_RESPONSE_ERROR: {
-            ac_response_error_t *o = (ac_response_error_t *) response;
-            printf("Request %d failed: %s (%d).\n",
-                   o->id,
-                   o->message,
-                   o->code);
-            break;
-        }
-        case AC_RESPONSE_CMD_OUT: {
-            ac_response_cmd_out_t *o = (ac_response_cmd_out_t *) response;
-            printf("Request %d output by %s: %s.\n",
-                   o->id,
-                   o->sender,
-                   o->out);
-            break;
-        }
-        case AC_RESPONSE_CMD_RESULT: {
-            ac_response_cmd_result_t *o = (ac_response_cmd_result_t *) response;
-            printf("Request %d is done: %s (%d).\n",
-                   o->id,
-                   o->success ? "Success" : "Failed",
-                   o->result);
-            break;
-        }
-        default: {
-            printf("Received an unrecognized response of type '%u'.\n",
-                   response->type);
-        }
-    }
-}
-
-#ifndef WIN32
-
-static void intr(int signum) {}
-
-#endif
-
-static int on_send(const void *sock,
-                   const void *buffer,
-                   const size_t len) {
-    int r;
-    printf("Writing %lu bytes.\n", len);
-    if ((r = net_send(sock, buffer, len))) {
-        fprintf(stderr, "Cannot write %lu bytes to server: %s (%d).\n",
-                len,
-                net_strerror(r),
-                r);
-    }
-    return r;
-}
-
-static int say(void *connection) {
-    int r;
-    ac_config_t conf = {
-            .name = "helloworld"
-    };
-    ac_request_cmd_t req = {
-            .type = AC_REQUEST_CMD,
-            .id = 100,
-            .config = &conf,
-            .cmd = "say Hi"
-    };
-    if ((r = ac_request(connection, (ac_request_t *) &req))) {
-        return r;
-    }
-    return 0;
-}
-
-int main(int argc, char **argv) {
-    int r;
-    if ((r = net_init())) {
-        return r;
-    }
-#if defined(THREAD_WIN32)
-    if (!(mtx_conn = CreateMutex(NULL, TRUE, NULL))) {
-        r = GetLastError();
-        fprintf(stderr, "Cannot create mutex: %d.\n", r);
-        return r;
-    }
-#elif defined(THREAD_C11)
-    if (mtx_init(&mtx_conn, mtx_plain) != thrd_success) {
-        fprintf(stderr, "Cannot create mutex.\n");
-        return 1;
-    }
-#endif
-
-#ifdef WIN32
-    fprintf(stderr, "Warning: ^C handler on Windows is not yet available.\n");
-#else
-    struct sigaction sa;
-    sa.sa_handler = intr;
-    sigemptyset(&sa.sa_mask);
-    sa.sa_flags = 0;
-    if (sigaction(SIGINT, &sa, NULL) ||
-        sigaction(SIGTERM, &sa, NULL)) {
-        const int e = errno;
-        fprintf(stderr, "Cannot set SIGINT or SIGTERM handlers: %s (%d).\n",
-                strerror(e),
-                e);
-        return e;
-    }
-#endif
-    libac_config_t config = {
-#ifdef DEBUG
-            .out = stderr,
-#else
-            .out = NULL,
-#endif
-            .tok = NULL
-    };
-    if ((r = ac_init(&config))) return r;
-    void *connection;
-    SOCKET sock;
-    ac_connection_parameters_t parameters = {
-            .host = "localhost",
-            .port = 25575,
-            .id = "1",
-            .token = "123",
-            .version = 0,
-            .sock = NULL,
-            .on_send = on_send
-    };
-    if ((r = net_connect(parameters.host, parameters.port, &sock))) {
-        fprintf(stderr, "Cannot connect to server: %s (%d).\n",
-                net_strerror(r),
-                r);
-        ac_free();
-        net_free();
-        return r;
-    }
-    parameters.sock = &sock;
-    if ((r = ac_connect(parameters, &connection))) {
-        net_close(&sock);
-        ac_free();
-        net_free();
-        return r;
-    }
-    ac_obj_t *obj;
-    int nr;
-    uint8_t buffer[1000U];
-    size_t bytes;
-    enum ac_connection_state state;
-    printf("Waiting until the connection is established.\n");
-    bool ready = false;
-    while (1) {
-        if ((nr = net_read(&sock, buffer, sizeof(buffer), &bytes, 10))) {
-            if (nr == NET_TIMEOUT) {
-                printf("Receive timeout.\n");
-                continue;
-            } else {
-                goto end;
-            }
-        }
-        if ((r = lock())) { goto end; }
-        if ((r = ac_receive(connection, buffer, bytes, &obj))) {
-            if ((r = unlock())) { goto end; }
-            goto end;
-        }
-        if (!ready) {
-            /* Wait until ready. */
-            if ((r = ac_get_state(connection, &state))) {
-                if ((r = unlock())) { goto end; }
-                goto end;
-            }
-            switch (state) {
-                case AC_STATE_INIT:
-                    continue;
-                case AC_STATE_READY:
-                    printf("Connection is established.\n");
-                    ready = true;
-                    say(connection);
-                    if ((r = unlock())) { goto end; }
-                    continue;
-                default:
-                    fprintf(stderr, "Unexpected state.\n");
-                    if ((r = unlock())) { goto end; }
-                    goto end;
-            }
-        }
-        if ((r = unlock())) { goto end; }
-
-        if (!obj) {
-            continue;
-        }
-        if (AC_IS_EVENT(obj->type)) {
-            handle_event((ac_event_t *) obj);
-        } else if (AC_IS_RESPONSE(obj->type)) {
-            handle_response((ac_response_t *) obj);
-        }
-        ac_object_free(obj);
-    }
-    end:
-    if (nr) {
-        if (nr == NET_CLOSED) {
-            fprintf(stderr, "Connection is closed while reading from the server.\n");
-        } else {
-            fprintf(stderr, "Cannot receive from server: %s (%d).\n",
-                    net_strerror(nr),
-                    nr);
-        }
-    }
-    if ((r = lock())) { goto end; }
-    ac_disconnect(connection, false);
-    if ((r = unlock())) { goto end; }
-    net_close(&sock);
-    ac_free();
-    net_free();
-#if defined(THREAD_WIN32)
-    CloseHandle(mtx_conn);
-#elif defined(THREAD_C11)
-    mtx_destroy(&mtx_conn);
-#endif
-    return r;
-}
\ No newline at end of file
diff --git a/client/libacron/apps/helloworld/net.c b/client/libacron/apps/helloworld/net.c
deleted file mode 100644
index 83192e0..0000000
--- a/client/libacron/apps/helloworld/net.c
+++ /dev/null
@@ -1,181 +0,0 @@
-/*
- * Created by yuuta on 7/22/22.
- *
- * A simple cross-platform (Unix and Windows) implementation of a socket client.
- */
-
-#include "net.h"
-
-#include <stdint.h>
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-
-#ifdef WIN32
-#include <windows.h> /* For DWORD */
-#include <winsock2.h>
-#include <ws2tcpip.h>
-
-#define errno_sock WSAGetLastError()
-
-#else
-
-#include <sys/socket.h>
-#include <netdb.h>
-#include <unistd.h>
-#include <sys/time.h>
-
-#define closesocket(socket) close(socket)
-#define errno_sock errno
-
-#endif
-
-int net_connect(const char *host,
-                const uint16_t port,
-                SOCKET *sock) {
-    int r;
-    struct addrinfo *res;
-    char service[6];
-
-    snprintf(service, 6, "%u", port);
-    if ((r = getaddrinfo(host, service, NULL, &res))) {
-        return r;
-    }
-
-    SOCKET fd;
-    if ((fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) <= 0) {
-        const int e = errno_sock;
-        freeaddrinfo(res);
-        return e;
-    }
-    if (connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
-        const int e = errno_sock;
-        closesocket(fd);
-        freeaddrinfo(res);
-        return e;
-    }
-    freeaddrinfo(res);
-    *sock = fd;
-    return 0;
-}
-
-int net_read(const SOCKET *sock,
-             void *buffer,
-             const size_t length,
-             size_t *read,
-             const unsigned int timeout) {
-
-#ifdef WIN32
-    DWORD to = timeout * 1000;
-    if (setsockopt(*sock, SOL_SOCKET, SO_RCVTIMEO, (const char*)&to, sizeof to)) {
-#else
-    struct timeval tv;
-    tv.tv_sec = timeout;
-    tv.tv_usec = 0;
-    if (setsockopt(*sock, SOL_SOCKET, SO_RCVTIMEO, (const char *) &tv, sizeof tv)) {
-#endif
-        return errno_sock;
-    }
-
-    int bytes;
-    if ((bytes = (int) recv(*sock, buffer, length, 0)) <= 0) {
-        if (bytes < 0) {
-            const int e = errno_sock;
-#ifdef WIN32
-            if (e == WSAETIMEDOUT) {
-#else
-            if (e == EAGAIN) {
-#endif
-                return NET_TIMEOUT;
-            }
-            return e;
-        }
-        return NET_CLOSED;
-    }
-    *read = bytes;
-    return 0;
-}
-
-int net_send(const SOCKET *sock,
-             const void *buffer,
-             size_t len) {
-    size_t pos;
-    const uint8_t *ptr = buffer;
-    int retval;
-
-    for (pos = 0U; pos < len; pos += retval) {
-        size_t n = len - pos;
-        retval = (int) send(*sock, &ptr[pos], (int) n, 0);
-        if (retval <= 0) {
-            return errno_sock;
-        }
-    }
-    return 0;
-}
-
-int net_init(void) {
-#ifdef WIN32
-    int r;
-    WORD wVersionRequested;
-    WSADATA wsaData;
-    wVersionRequested = MAKEWORD(2, 2);
-    if ((r = WSAStartup(wVersionRequested, &wsaData))) {
-        fprintf(stderr, "WSAStartup failed with error: %d\n", r);
-        return r;
-    }
-    if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2) {
-        fprintf(stderr, "Could not find a usable version of Winsock.dll\n");
-        WSACleanup();
-        return 1;
-    }
-#endif
-    return 0;
-}
-
-void net_close(const SOCKET *sock) {
-    closesocket(*sock);
-}
-
-#ifdef WIN32
-static __declspec( thread ) LPTSTR err_buf = NULL;
-#else
-static _Thread_local char err_buf[1024];
-#endif
-
-void net_free(void) {
-#ifdef WIN32
-    WSACleanup();
-    if (err_buf) {
-        LocalFree(err_buf);
-        err_buf = NULL;
-    }
-#endif
-}
-
-char *net_strerror(int errnum) {
-#ifdef WIN32
-    if (err_buf) {
-        LocalFree(err_buf);
-        err_buf = NULL;
-    }
-    FormatMessage(
-            FORMAT_MESSAGE_FROM_SYSTEM |
-            FORMAT_MESSAGE_ALLOCATE_BUFFER |
-            FORMAT_MESSAGE_IGNORE_INSERTS,
-            NULL,
-            errnum,
-            MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
-            (LPTSTR) &err_buf,
-            0,
-            NULL);
-    if (!err_buf) {
-        return "Unknown error";
-    }
-#else
-    int r;
-    if ((r = strerror_r(errnum, err_buf, sizeof(err_buf) / sizeof(char)))) {
-        snprintf(err_buf, 1024, "%d (%d)", errnum, r);
-    }
-#endif
-    return err_buf;
-}
\ No newline at end of file
diff --git a/client/libacron/apps/helloworld/net.h b/client/libacron/apps/helloworld/net.h
deleted file mode 100644
index 1a49709..0000000
--- a/client/libacron/apps/helloworld/net.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * Created by yuuta on 7/23/22.
- */
-
-#ifndef ACRONC_NET_H
-#define ACRONC_NET_H
-
-#include <stdint.h>
-#include <stddef.h>
-
-#ifdef WIN32
-#include <winsock2.h>
-
-#else
-
-#define SOCKET int
-
-#endif
-
-#define NET_CLOSED  -2
-#define NET_TIMEOUT -1
-
-int net_connect(const char *host,
-                uint16_t port,
-                SOCKET *sock);
-
-int net_read(const SOCKET *sock,
-             void *buffer,
-             size_t length,
-             size_t *read,
-             unsigned int timeout);
-
-int net_send(const SOCKET *sock,
-             const void *buffer,
-             size_t len);
-
-void net_close(const SOCKET *sock);
-
-int net_init(void);
-
-void net_free(void);
-
-char *net_strerror(int errnum);
-
-#endif /* ACRONC_NET_H */