Changeset 99c2e9f3 in mainline

Timestamp:

2012-01-12T09:29:00Z (12 years ago)

Author:

Vojtech Horky <vojtechhorky@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

2a180307

Parents:

261bbdc

Message:

remcons: more refactoring

Location:

uspace/srv/hid/remcons

Files:

• remcons.c (modified) (9 diffs)
• user.c (modified) (1 diff)
• user.h (modified) (2 diffs)

uspace/srv/hid/remcons/remcons.c

@@ -74 +74 @@
     sizeof(telnet_force_character_mode_command) / sizeof(telnet_cmd_t);
 
-/** Creates new keyboard event from given char.
- *
- * @param type Event type (press / release).
- * @param c Pressed character.
- */
-static kbd_event_t* new_kbd_event(kbd_event_type_t type, wchar_t c) {
-        kbd_event_t *event = malloc(sizeof(kbd_event_t));
-        assert(event);
-
-        link_initialize(&event->link);
-        event->type = type;
-        event->c = c;
-        event->mods = 0;
-        event->key = (c == '\n' ? KC_ENTER : KC_A);
-
-        return event;
-}
 
 /** Handling client requests (VFS and console interface).
@@ -101 +84 @@
                 ipc_call_t call;
                 ipc_callid_t callid = 0;
+
+                /*
+                 * The getterm task might terminate while we are here,
+                 * waiting for a call. Also, the socket might be closed
+                 * meanwhile.
+                 * We want to detect this situation early, so we use a
+                 * timeout variant of async_get_call().
+                 */
                 while (callid == 0) {
                         callid = async_get_call_timeout(&call, 1000);
 
-                        fibril_mutex_lock(&user->guard);
-                        bool bail_out = user->socket_closed || user->task_finished;
-                        fibril_mutex_unlock(&user->guard);
-
-                        if (bail_out) {
+                        if (telnet_user_is_zombie(user)) {
                                 if (callid != 0) {
                                         async_answer_0(callid, EINTR);
@@ -117 +104 @@
                 
                 if (!IPC_GET_IMETHOD(call)) {
-                        /* Clean-up. */
                         return;
                 }
@@ -129 +115 @@
                         break;
                 case CONSOLE_GET_EVENT: {
-                        if (list_empty(&user->in_events.list)) {
-                                retry:
-                                if (user->socket_buffer_len <= user->socket_buffer_pos) {
-                                        int recv_length = recv(user->socket, user->socket_buffer, BUFFER_SIZE, 0);
-                                        if ((recv_length == 0) || (recv_length == ENOTCONN)) {
-                                                fibril_mutex_lock(&user->guard);
-                                                user->socket_closed = true;
-                                                fibril_mutex_unlock(&user->guard);
-                                                async_answer_0(callid, ENOENT);
-                                                return;
-                                        }
-                                        if (recv_length < 0) {
-                                                async_answer_0(callid, EINVAL);
-                                                return;
-                                        }
-                                        user->socket_buffer_len = recv_length;
-                                        user->socket_buffer_pos = 0;
-                                }
-                                char data = user->socket_buffer[user->socket_buffer_pos++];
-                                if (data == 13) {
-                                        data = 10;
-                                }
-                                if (data == 0)
-                                        goto retry;
-
-                                kbd_event_t *down = new_kbd_event(KEY_PRESS, data);
-                                kbd_event_t *up = new_kbd_event(KEY_RELEASE, data);
-                                assert(down);
-                                assert(up);
-                                prodcons_produce(&user->in_events, &down->link);
-                                prodcons_produce(&user->in_events, &up->link);
-                        }
-
-
-                        link_t *link = prodcons_consume(&user->in_events);
-                        kbd_event_t *event = list_get_instance(link, kbd_event_t, link);
-                        async_answer_4(callid, EOK, event->type, event->key, event->mods, event->c);
-                        free(event);
+                        kbd_event_t event;
+                        int rc = telnet_user_get_next_keyboard_event(user, &event);
+                        if (rc != EOK) {
+                                /* Silently ignore. */
+                                async_answer_0(callid, EOK);
+                                break;
+                        }
+                        async_answer_4(callid, EOK, event.type, event.key, event.mods, event.c);
                         break;
                 }
@@ -185 +141 @@
                                 break;
                         }
-                        buf_converted = malloc(2 * size);
+                        buf_converted = malloc(2 * size + 1);
                         assert(buf_converted);
                         int buf_converted_size = 0;
@@ -197 +153 @@
                                 }
                         }
+                        /* Add terminating zero for printing purposes. */
+                        buf_converted[buf_converted_size] = 0;
+
+                        fibril_mutex_lock(&user->guard);
                         rc = send(user->socket, buf_converted, buf_converted_size, 0);
+                        fibril_mutex_unlock(&user->guard);
                         free(buf);
 
@@ -206 +167 @@
 
                         async_answer_1(callid, EOK, size);
-
                         break;
                 }
@@ -249 +209 @@
                 return;
         }
+        async_answer_0(iid, EOK);
 
         telnet_user_log(user, "New client connected (%" PRIxn").", iid);
-
-        /* Accept the connection, increment reference. */
-        async_answer_0(iid, EOK);
 
         /* Force character mode. */
@@ -259 +217 @@
             telnet_force_character_mode_command_count, 0);
 
+        /* Handle messages. */
         client_connection_message_loop(user);
 
-        /* Announce user disconnection. */
         telnet_user_notify_client_disconnected(user);
         telnet_user_log(user, "Client disconnected (%" PRIxn").", iid);

uspace/srv/hid/remcons/user.c

@@ -172 +172 @@
 }
 
+/** Tell whether the launched task already exited and socket is already closed.
+ *
+ * @param user Telnet user in question.
+ */
+bool telnet_user_is_zombie(telnet_user_t *user)
+{
+        fibril_mutex_lock(&user->guard);
+        bool zombie = user->socket_closed || user->task_finished;
+        fibril_mutex_unlock(&user->guard);
+
+        return zombie;
+}
+
+/** Receive next byte from a socket (use buffering.
+ * We need to return the value via extra argument because the read byte
+ * might be negative.
+ */
+static int telnet_user_recv_next_byte_no_lock(telnet_user_t *user, char *byte)
+{
+        /* No more buffered data? */
+        if (user->socket_buffer_len <= user->socket_buffer_pos) {
+                int recv_length = recv(user->socket, user->socket_buffer, BUFFER_SIZE, 0);
+                if ((recv_length == 0) || (recv_length == ENOTCONN)) {
+                        user->socket_closed = true;
+                        return ENOENT;
+                }
+                if (recv_length < 0) {
+                        return recv_length;
+                }
+                user->socket_buffer_len = recv_length;
+                user->socket_buffer_pos = 0;
+        }
+
+        *byte = user->socket_buffer[user->socket_buffer_pos++];
+
+        return EOK;
+}
+
+/** Creates new keyboard event from given char.
+ *
+ * @param type Event type (press / release).
+ * @param c Pressed character.
+ */
+static kbd_event_t* new_kbd_event(kbd_event_type_t type, wchar_t c) {
+        kbd_event_t *event = malloc(sizeof(kbd_event_t));
+        assert(event);
+
+        link_initialize(&event->link);
+        event->type = type;
+        event->c = c;
+        event->mods = 0;
+        event->key = (c == '\n' ? KC_ENTER : KC_A);
+
+        return event;
+}
+
+int telnet_user_get_next_keyboard_event(telnet_user_t *user, kbd_event_t *event)
+{
+        fibril_mutex_lock(&user->guard);
+        if (list_empty(&user->in_events.list)) {
+                char next_byte = 0;
+                /* Skip zeros, bail-out on error. */
+                while (next_byte == 0) {
+                        int rc = telnet_user_recv_next_byte_no_lock(user, &next_byte);
+                        DEBUG("Got %d.\n", next_byte);
+                        if (rc != EOK) {
+                                fibril_mutex_unlock(&user->guard);
+                                return rc;
+                        }
+                }
+
+                /* CR-LF conversions. */
+                if (next_byte == 13) {
+                        next_byte = 10;
+                }
+
+                kbd_event_t *down = new_kbd_event(KEY_PRESS, next_byte);
+                kbd_event_t *up = new_kbd_event(KEY_RELEASE, next_byte);
+                assert(down);
+                assert(up);
+                prodcons_produce(&user->in_events, &down->link);
+                prodcons_produce(&user->in_events, &up->link);
+        }
+
+        link_t *link = prodcons_consume(&user->in_events);
+        kbd_event_t *tmp = list_get_instance(link, kbd_event_t, link);
+
+        fibril_mutex_unlock(&user->guard);
+
+        *event = *tmp;
+
+        free(tmp);
+
+        return EOK;
+}
 
 /**

uspace/srv/hid/remcons/user.h

@@ -40 +40 @@
 #include "remcons.h"
 
-#define BUFFER_SIZE 1024
+#define BUFFER_SIZE 32
 
 /** Representation of a connected (human) user. */
@@ -76 +76 @@
 void telnet_user_destroy(telnet_user_t *user);
 telnet_user_t *telnet_user_get_for_client_connection(service_id_t id);
+bool telnet_user_is_zombie(telnet_user_t *user);
 void telnet_user_notify_client_disconnected(telnet_user_t *user);
+int telnet_user_get_next_keyboard_event(telnet_user_t *user, kbd_event_t *event);
 
 /** Print informational message about connected user. */