/**
* 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 (colour_list_create(&colours, 64) < 0); stage++;
fail_if (mds_message_initialise(&received));
return 0;
fail:
xperror(*argv);
if (stage >= 2) colour_list_destroy(&colours);
if (stage >= 1) mds_message_destroy(&received);
return 1;
}
/**
* Wait for confirmation that we may switch virtual terminal
*
* @param data Thread input parameter, will always be `NULL`
* @return Thread return value, will always be `NULL`
*/
void* secondary_loop(void* data)
{
mds_message_t secondary_received;
int r;
(void) data;
secondary_thread_started = 1;
fail_if (mds_message_initialise(&secondary_received) < 0);
while (!reexecing && !terminating)
{
if (r = mds_message_read(&secondary_received, secondary_socket_fd), r == 0)
r = vt_accept_switch(display_tty_fd);
if (r == 0)
continue;
if (r == -2)
{
eprint("corrupt message received, aborting.");
secondary_thread_failed = 1;
goto done;
}
else if (errno == EINTR)
continue;
else
fail_if (errno != ECONNRESET);
eprint("lost secondary connection to server.");
mds_message_destroy(&secondary_received);
mds_message_initialise(&secondary_received);
fail_if (reconnect_fd_to_display(&secondary_socket_fd) < 0);
}
goto done;
fail:
xperror(*argv);
secondary_thread_failed = 1;
done:
secondary_thread_started = 0;
mds_message_destroy(&secondary_received);
if (!reexecing && !terminating)
pthread_kill(master_thread, SIGTERM);
return NULL;
}
/**
* 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;
colour_list_pack(&colours);
free(colour_list_buffer_without_values);
colour_list_buffer_without_values = NULL;
free(colour_list_buffer_with_values);
colour_list_buffer_with_values = NULL;
}
if (!(r = mds_message_read(&received, socket_fd)))
if (!(r = handle_message()))
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);
colour_list_destroy(&colours);
}
free(send_buffer);
free(colour_list_buffer_without_values);
free(colour_list_buffer_with_values);
return rc;
}
/**
* Perform the server's mission
*
* @return Non-zero on error
*/
int master_loop(void)
{
int rc = 1, r;
while (!reexecing && !terminating)
{
if (switching_vt)
{
int leaving = switching_vt == 1;
switching_vt = 0;
r = switch_vt(leaving);
}
else
if (r = mds_message_read(&received, socket_fd), r == 0)
r = handle_message();
if (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 primary connection to server.");
mds_message_destroy(&received);
mds_message_initialise(&received);
connected = 0;
fail_if (reconnect_to_display());
connected = 1;
}
rc = 0;
if (vt_set_exclusive(display_tty_fd, 0) < 0) xperror(*argv);
if (vt_set_graphical(display_tty_fd, 0) < 0) xperror(*argv);
if (unlink(vtfile_path) < 0)
xperror(*argv);
vt_close(display_tty_fd, &old_vt_stat);
goto done;
fail:
xperror(*argv);
done:
rc |= secondary_thread_failed;
if (rc || !reexecing)
mds_message_destroy(&received);
if ((errno = pthread_join(secondary_thread, NULL)))
xperror(*argv);
return rc;
}
/**
* 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: 14\n"
"\n"
"Command: echo\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;
}
/**
* Perform the server's mission
*
* @return Non-zero on error
*/
int
master_loop(void)
{
int rc = 1, r;
while (!reexecing && !terminating) {
if (!(r = mds_message_read(&received, socket_fd)))
if (!(r = echo_message()))
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(echo_buffer);
return rc;
}
/**
* This function should initialise the server,
* and it not invoked after a re-exec.
*
* @return Non-zero on error
*/
int initialise_server(void)
{
struct vt_mode mode;
char* display_env;
int primary_socket_fd;
int stage = 0;
const char* const message =
"Command: intercept\n"
"Message ID: 0\n"
"Length: 38\n"
"\n"
"Command: get-vt\n"
"Command: configure-vt\n";
const char* const secondary_message =
"Command: intercept\n"
"Message ID: 0\n"
"Priority: -4611686018427387904\n" /* −2⁶² */
"Length: 22\n"
"\n"
"Command: switching-vt\n";
primary_socket_fd = socket_fd;
fail_if (connect_to_display());
secondary_socket_fd = socket_fd;
socket_fd = primary_socket_fd;
display_env = getenv("MDS_DISPLAY");
display_env = display_env ? strchr(display_env, ':') : NULL;
if ((display_env == NULL) || (strlen(display_env) < 2))
goto no_display;
memset(vtfile_path, 0, sizeof(vtfile_path));
xsnprintf(vtfile_path, "%s/%s.vt", MDS_RUNTIME_ROOT_DIRECTORY, display_env + 1);
stage = 1;
if (is_respawn == 0)
{
display_vt = select_vt();
fail_if (display_vt < 0);
display_tty_fd = vt_open(display_vt, &old_vt_stat);
fail_if (write_vt_file() < 0);
fail_if (vt_set_active(display_vt) < 0);
}
else
{
fail_if (read_vt_file() < 0);
vt_is_active = (display_vt == vt_get_active());
fail_if (vt_is_active < 0);
}
fail_if (full_send(secondary_socket_fd, secondary_message, strlen(secondary_message)));
fail_if (full_send(socket_fd, message, strlen(message)));
fail_if (server_initialised() < 0);
fail_if (mds_message_initialise(&received)); stage = 2;
fail_if (xsigaction(SIGRTMIN + 2, received_switch_vt) < 0);
fail_if (xsigaction(SIGRTMIN + 3, received_switch_vt) < 0);
vt_construct_mode(1, SIGRTMIN + 2, SIGRTMIN + 3, &mode);
fail_if (vt_get_set_mode(display_tty_fd, 1, &mode) < 0);
if (vt_set_exclusive(display_tty_fd, 1) < 0)
xperror(*argv);
return 0;
no_display:
eprint("no display has been set, how did this happen.");
return 1;
fail:
xperror(*argv);
if (stage >= 1)
unlink(vtfile_path);
if (display_tty_fd >= 0)
vt_close(display_tty_fd, &old_vt_stat);
if (stage >= 2)
mds_message_destroy(&received);
return 1;
}
