1 files changed, 151 insertions, 0 deletions
diff --git a/client/applets/applet.c b/client/applets/applet.c
new file mode 100644
index 0000000..3f02e60
--- /dev/null
+++ b/client/applets/applet.c
@@ -0,0 +1,151 @@
+#include "applet.h"
+
+#include <libac.h>
+#include <stdio.h>
+#include <sys/socket.h>
+#include <err.h>
+#include <errno.h>
+#include <arpa/inet.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+static int fd = 0;
+void *connection = NULL;
+
+const char *get_world(enum ac_world world) {
+    switch (world) {
+        case overworld: return "overworld";
+        case nether: return "nether";
+        case end: return "end";
+        default: return "unknown";
+    }
+}
+
+static void cleanup(void) {
+    if (connection) ac_disconnect(connection, false);
+    if (fd) close(fd);
+    ac_free();
+}
+
+static void intr(int signum) {}
+
+static int on_send(const void *sock,
+        const void *buffer,
+        const 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(fd, &ptr[pos], (int) n, 0);
+        if (retval < 0) {
+            const int e = errno;
+            perror("Cannot write to socket");
+            return e;
+        }
+    }
+    return 0;
+}
+
+/* Move init to a separate function from main() so we do not need to keep those stack variables all the time. */
+static void init(void) { 
+    const char *id = getenv("ID");
+    const char *token = getenv("TOKEN");
+    if (!id) errx(64, "Required envvar: ID");
+    if (!token) errx(64, "Required envvar: TOKEN");
+
+    atexit(cleanup);
+    int r;
+    if ((fd = socket(AF_INET, SOCK_STREAM, 0)) <= 0) err(errno, "Cannot create socket");
+    struct in_addr ad = {
+        .s_addr = 127 | 0 << 8 | 0 << 16 | 1 << 24
+    };
+    struct sockaddr_in addr = {
+        .sin_family = AF_INET,
+        .sin_port = htons(PORT),
+        .sin_addr = ad
+    };
+    if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) err(errno, "Cannot connect to server");
+    libac_config_t libac_conf = {
+        .tok = NULL,
+#ifdef DEBUG
+        .out = stderr,
+#else
+        .out = NULL
+#endif
+    };
+    if ((r = ac_init(&libac_conf))) errx(r, "Cannot start libac: %d.", r);
+    ac_connection_parameters_t param = {
+        .host = "127.0.0.1",
+        .port = PORT,
+        .id = (char *) id,
+        .token = (char *) token,
+        .version = 0,
+        .sock = &fd,
+        .on_send = on_send
+    };
+    if ((r = ac_connect(param, &connection))) errx(r, "Cannot connect to server: %d.", r);
+    struct sigaction sa;
+    sa.sa_handler = intr;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    if (sigaction(SIGINT, &sa, NULL) == -1) err(errno, "Cannot set SIGINT handler.");
+    if (sigaction(SIGTERM, &sa, NULL) == -1) err(errno, "Cannot set SIGTERM handler.");
+}
+
+int main(void) {
+    init();
+    int r;
+    int bytes;
+    uint8_t buffer[1024U];
+    ac_obj_t *obj = NULL;
+    bool ready = false;
+    while (1) {
+        if ((bytes = (int) recv(fd, buffer, sizeof(buffer), 0)) <= 0) {
+            if (bytes < 0) {
+                if (errno == EAGAIN) continue;
+                if (errno == EINTR) {
+                    printf("Exit.\n");
+                    return 0;
+                }
+                err(errno, "Cannot read from socket");
+            }
+            errx(1, "Connection aborted");
+        }
+        size_t pos = 0;
+        size_t read = 0;
+        bool again = false;
+        while (pos < bytes || again) {
+            if (again) {
+                r = ac_receive(connection, NULL, 0, 0, &obj, NULL);
+                again = false;
+            } else {
+                r = ac_receive(connection, buffer, pos, bytes, &obj, &read);
+                pos += read;
+            }
+            if (r == AC_E_AGAIN) {
+                again = true;
+            } else if (r) {
+                errx(r, "Cannot parse server response: %d.", r);
+            }
+            if (!ready) {
+                enum ac_connection_state state;
+                if ((r = ac_get_state(connection, &state))) {
+                    errx(r, "Cannot read state: %d.", r);
+                }
+                if (state == AC_STATE_READY) {
+                    printf("Connected.\n");
+                    ready = true;
+                    continue;
+                }
+            }
+            if (!obj) {
+                continue;
+            }
+        }
+    }
+}