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-rw-r--r--src/mds-colour.c323
-rw-r--r--src/mds-colour.h44
2 files changed, 367 insertions, 0 deletions
diff --git a/src/mds-colour.c b/src/mds-colour.c
new file mode 100644
index 0000000..267c0ba
--- /dev/null
+++ b/src/mds-colour.c
@@ -0,0 +1,323 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "mds-colour.h"
+/* TODO reload settings on SIGUSR2 */
+/* TODO --save-changes */
+
+#include <libmdsserver/macros.h>
+#include <libmdsserver/util.h>
+#include <libmdsserver/mds-message.h>
+
+#include <errno.h>
+#include <inttypes.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#define reconnect_to_display() -1
+
+
+
+#define MDS_COLOUR_VARS_VERSION 0
+
+
+
+/**
+ * This variable should declared by the actual server implementation.
+ * It must be configured before `main` is invoked.
+ *
+ * This tells the server-base how to behave
+ */
+server_characteristics_t server_characteristics =
+ {
+ .require_privileges = 0,
+ .require_display = 1,
+ .require_respawn_info = 0,
+ .sanity_check_argc = 1,
+ .fork_for_safety = 0,
+ .danger_is_deadly = 0
+ };
+
+
+
+/**
+ * Value of the ‘Message ID’ header for the next message
+ */
+static uint32_t message_id = 1;
+
+/**
+ * Buffer for received messages
+ */
+static mds_message_t received;
+
+/**
+ * Whether the server is connected to the display
+ */
+static int connected = 1;
+
+/**
+ * Buffer for sending messages
+ */
+static char* send_buffer = NULL;
+
+/**
+ * The size allocated to `send_buffer` divided by `sizeof(char)`
+ */
+static size_t send_buffer_size = 0;
+
+
+
+/**
+ * This function will be invoked before `initialise_server` (if not re-exec:ing)
+ * or before `unmarshal_server` (if re-exec:ing)
+ *
+ * @return Non-zero on error
+ */
+int __attribute__((const)) preinitialise_server(void)
+{
+ return 0;
+}
+
+
+/**
+ * This function should initialise the server,
+ * and it not invoked after a re-exec.
+ *
+ * @return Non-zero on error
+ */
+int initialise_server(void)
+{
+ int stage = 0;
+ const char* const message =
+ "Command: intercept\n"
+ "Message ID: 0\n"
+ "Length: 62\n"
+ "\n"
+ "Command: list-colours\n"
+ "Command: get-colour\n"
+ "Command: set-colour\n";
+
+ fail_if (full_send(message, strlen(message)));
+ fail_if (server_initialised() < 0); stage++;
+ fail_if (mds_message_initialise(&received));
+
+ return 0;
+ fail:
+ xperror(*argv);
+ if (stage == 1)
+ mds_message_destroy(&received);
+ return 1;
+}
+
+
+/**
+ * This function will be invoked after `initialise_server` (if not re-exec:ing)
+ * or after `unmarshal_server` (if re-exec:ing)
+ *
+ * @return Non-zero on error
+ */
+int postinitialise_server(void)
+{
+ if (connected)
+ return 0;
+
+ fail_if (reconnect_to_display());
+ connected = 1;
+ return 0;
+ fail:
+ mds_message_destroy(&received);
+ return 1;
+}
+
+
+/**
+ * Calculate the number of bytes that will be stored by `marshal_server`
+ *
+ * On failure the program should `abort()` or exit by other means.
+ * However it should not be possible for this function to fail.
+ *
+ * @return The number of bytes that will be stored by `marshal_server`
+ */
+size_t marshal_server_size(void)
+{
+ return 2 * sizeof(int) + sizeof(uint32_t) + mds_message_marshal_size(&received);
+}
+
+
+/**
+ * Marshal server implementation specific data into a buffer
+ *
+ * @param state_buf The buffer for the marshalled data
+ * @return Non-zero on error
+ */
+int marshal_server(char* state_buf)
+{
+ buf_set_next(state_buf, int, MDS_COLOUR_VARS_VERSION);
+ buf_set_next(state_buf, int, connected);
+ buf_set_next(state_buf, uint32_t, message_id);
+ mds_message_marshal(&received, state_buf);
+
+ mds_message_destroy(&received);
+ return 0;
+}
+
+
+/**
+ * Unmarshal server implementation specific data and update the servers state accordingly
+ *
+ * On critical failure the program should `abort()` or exit by other means.
+ * That is, do not let `reexec_failure_recover` run successfully, if it unrecoverable
+ * error has occurred or one severe enough that it is better to simply respawn.
+ *
+ * @param state_buf The marshalled data that as not been read already
+ * @return Non-zero on error
+ */
+int unmarshal_server(char* state_buf)
+{
+ /* buf_get_next(state_buf, int, MDS_COLOUR_VARS_VERSION); */
+ buf_next(state_buf, int, 1);
+ buf_get_next(state_buf, int, connected);
+ buf_get_next(state_buf, uint32_t, message_id);
+ fail_if (mds_message_unmarshal(&received, state_buf));
+ return 0;
+ fail:
+ xperror(*argv);
+ mds_message_destroy(&received);
+ return -1;
+}
+
+
+/**
+ * Attempt to recover from a re-exec failure that has been
+ * detected after the server successfully updated it execution image
+ *
+ * @return Non-zero on error
+ */
+int __attribute__((const)) reexec_failure_recover(void)
+{
+ return -1;
+}
+
+
+/**
+ * Perform the server's mission
+ *
+ * @return Non-zero on error
+ */
+int master_loop(void)
+{
+ int rc = 1, r;
+
+ while (!reexecing && !terminating)
+ {
+ if (danger)
+ {
+ danger = 0;
+ free(send_buffer), send_buffer = NULL;
+ send_buffer_size = 0;
+ }
+
+ if (r = mds_message_read(&received, socket_fd), r == 0)
+ if (r = handle_message(), r == 0)
+ continue;
+
+ if (r == -2)
+ {
+ eprint("corrupt message received, aborting.");
+ goto done;
+ }
+ else if (errno == EINTR)
+ continue;
+ else
+ fail_if (errno != ECONNRESET);
+
+ eprint("lost connection to server.");
+ mds_message_destroy(&received);
+ mds_message_initialise(&received);
+ connected = 0;
+ fail_if (reconnect_to_display());
+ connected = 1;
+ }
+
+ rc = 0;
+ goto done;
+ fail:
+ xperror(*argv);
+ done:
+ if (rc || !reexecing)
+ mds_message_destroy(&received);
+ free(send_buffer);
+ return rc;
+}
+
+
+/**
+ * Handle the received message
+ *
+ * @return Zero on success, -1 on error
+ */
+int handle_message(void)
+{
+}
+
+
+/**
+ * Send a full message even if interrupted
+ *
+ * @param message The message to send
+ * @param length The length of the message
+ * @return Zero on success, -1 on error
+ */
+int full_send(const char* message, size_t length)
+{
+ size_t sent;
+
+ while (length > 0)
+ {
+ sent = send_message(socket_fd, message, length);
+ if (sent > length)
+ {
+ eprint("Sent more of a message than exists in the message, aborting.");
+ return -1;
+ }
+ else
+ fail_if ((sent < length) && (errno != EINTR));
+ message += sent;
+ length -= sent;
+ }
+ return 0;
+ fail:
+ xperror(*argv);
+ return -1;
+}
+
+
+/**
+ * This function is called when a signal that
+ * signals that the system to dump state information
+ * and statistics has been received
+ *
+ * @param signo The signal that has been received
+ */
+void received_info(int signo)
+{
+ (void) signo;
+ iprintf("next message ID: %" PRIu32, message_id);
+ iprintf("connected: %s", connected ? "yes" : "no");
+ iprintf("send buffer size: %zu bytes", send_buffer_size);
+}
+
diff --git a/src/mds-colour.h b/src/mds-colour.h
new file mode 100644
index 0000000..f8f7d6e
--- /dev/null
+++ b/src/mds-colour.h
@@ -0,0 +1,44 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MDS_MDS_COLOUR_H
+#define MDS_MDS_COLOUR_H
+
+
+#include "mds-base.h"
+
+
+/**
+ * Handle the received message
+ *
+ * @return Zero on success, -1 on error
+ */
+int handle_message(void);
+
+
+/**
+ * Send a full message even if interrupted
+ *
+ * @param message The message to send
+ * @param length The length of the message
+ * @return Zero on success, -1 on error
+ */
+int full_send(const char* message, size_t length);
+
+
+#endif
+
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