X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=gui.c;h=a4f1717c2a996568d2fe36cc3a010f165ff1bcd9;hp=8d84e463d41dcdb0426b905b2208f5118c149f2c;hb=3b0a8fdb191309652e71e104a8f3705d55a93d3e;hpb=96fbecf492a660afbe7cbd5d45ae1dbe02f3acbf

diff --git a/gui.c b/gui.c
index 8d84e463..a4f1717c 100644
--- a/gui.c
+++ b/gui.c
@@ -1,8 +1,4 @@
-/*
- * Copyright (C) 1998-2014 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 1998 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file gui.c Curses-based interface for paraslash. */
 
@@ -12,10 +8,12 @@
 #include <curses.h>
 #include <locale.h>
 #include <sys/time.h>
+#include <lopsub.h>
 
-#include "gui.cmdline.h"
+#include "gui.lsg.h"
 #include "para.h"
 #include "gui.h"
+#include "lsu.h"
 #include "string.h"
 #include "ringbuffer.h"
 #include "fd.h"
@@ -23,18 +21,30 @@
 #include "list.h"
 #include "sched.h"
 #include "signal.h"
-#include "ggo.h"
 #include "version.h"
 
-/** define the array of error lists needed by para_gui */
-INIT_GUI_ERRLISTS;
+/** Array of error strings. */
+DEFINE_PARA_ERRLIST;
+
+static struct lls_parse_result *cmdline_lpr, *lpr;
+
+#define CMD_PTR (lls_cmd(0, gui_suite))
+#define OPT_RESULT(_name) (lls_opt_result(LSG_GUI_PARA_GUI_OPT_ ## _name, lpr))
+#define OPT_GIVEN(_name) (lls_opt_given(OPT_RESULT(_name)))
+#define OPT_STRING_VAL(_name) (lls_string_val(0, OPT_RESULT(_name)))
+#define OPT_UINT32_VAL(_name) (lls_uint32_val(0, OPT_RESULT(_name)))
+#define FOR_EACH_KEY_MAP(_i) for (_i = 0; _i < OPT_GIVEN(KEY_MAP); _i++)
+
 static char *stat_content[NUM_STAT_ITEMS];
 
 static struct gui_window {
 	WINDOW *win;
+	bool needs_update;
 } top, bot, sb, in, sep;
 
+/** How many lines of output to remember. */
 #define RINGBUFFER_SIZE 512
+
 struct rb_entry {
 	char *msg;
 	size_t len;
@@ -43,17 +53,15 @@ struct rb_entry {
 static struct ringbuffer *bot_win_rb;
 
 static unsigned scroll_position;
-
 static pid_t exec_pid;
-
 static int exec_fds[2] = {-1, -1};
-static struct gui_args_info conf;
 static int loglevel;
 
+/** Type of the process currently being executed. */
 enum exec_status {
-	EXEC_IDLE, /* no command running */
-	EXEC_DCMD, /* para or display command running */
-	EXEC_XCMD, /* external command running */
+	EXEC_IDLE, /**< No process running. */
+	EXEC_DCMD, /**< para or display process running. */
+	EXEC_XCMD, /**< External process running. */
 };
 
 /**
@@ -120,27 +128,29 @@ GUI_COMMANDS
 static struct gui_command command_list[] = {GUI_COMMANDS {.name = NULL}};
 
 struct input_task {
-	struct task task;
+	struct task *task;
 };
 
 struct status_task {
-	struct task task;
+	struct task *task;
+	pid_t pid;
 	char *buf;
 	int bufsize, loaded;
 	struct timeval next_exec;
 	int fd;
 };
 
+/** Stdout/stderr of the executing process is read in chunks of this size. */
 #define COMMAND_BUF_SIZE 32768
 
 struct exec_task {
-	struct task task;
+	struct task *task;
 	char command_buf[2][COMMAND_BUF_SIZE]; /* stdout/stderr of command */
 	int cbo[2]; /* command buf offsets */
 	unsigned flags[2]; /* passed to for_each_line() */
 };
 
-static int find_cmd_byname(char *name)
+static int find_cmd_byname(const char *name)
 {
 	int i;
 
@@ -238,10 +248,10 @@ static char *km_keyname(int c)
 }
 
 /* Print given number of spaces to curses window. */
-static void add_spaces(WINDOW* win, unsigned int num)
+static void add_spaces(WINDOW *win, unsigned int num)
 {
-	char space[] = "                                ";
-	unsigned sz = sizeof(space) - 1; /* number of spaces */
+	const char space[] = "                                ";
+	const unsigned sz = sizeof(space) - 1; /* number of spaces */
 
 	while (num >= sz)  {
 		waddstr(win, space);
@@ -249,53 +259,57 @@ static void add_spaces(WINDOW* win, unsigned int num)
 	}
 	if (num > 0) {
 		assert(num < sz);
-		space[num] = '\0';
-		waddstr(win, space);
+		waddstr(win, space + sz - num);
 	}
 }
 
 /*
- * print aligned string to curses window. This function always prints
+ * Print aligned string to curses window. This function always prints
  * exactly len chars.
  */
-static int align_str(WINDOW* win, char *str, unsigned int len,
+static int align_str(WINDOW *win, const char *str, unsigned int len,
 		unsigned int align)
 {
-	int ret, i, num; /* of spaces */
+	int ret, num; /* of spaces */
 	size_t width;
+	char *sstr; /* sanitized string */
 
 	if (!win || !str)
 		return 0;
-	ret = strwidth(str, &width);
+	ret = sanitize_str(str, len, &sstr, &width);
 	if (ret < 0) {
 		PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 		width = 0;
-		str[0] = '\0';
+		sstr = para_strdup(NULL);
 	}
+	assert(width <= len);
 	num = len - width;
-	if (num < 0) {
-		str[len] = '\0';
-		num = 0;
-	}
-	/* replace control characters by spaces */
-	for (i = 0; i < len && str[i]; i++) {
-		if (str[i] == '\n' || str[i] == '\r' || str[i] == '\f')
-			str[i] = ' ';
-	}
 	if (align == LEFT) {
-		waddstr(win, str);
+		waddstr(win, sstr);
 		add_spaces(win, num);
 	} else if (align == RIGHT) {
 		add_spaces(win, num);
-		waddstr(win, str);
+		waddstr(win, sstr);
 	} else {
 		add_spaces(win, num / 2);
-		waddstr(win, str[0]? str: "");
+		waddstr(win, sstr);
 		add_spaces(win, num - num / 2);
 	}
+	free(sstr);
 	return 1;
 }
 
+static void refresh_window(struct gui_window *gw)
+{
+	gw->needs_update = true;
+}
+
+static bool window_update_needed(void)
+{
+	return top.needs_update || bot.needs_update || sb.needs_update ||
+		in.needs_update || sep.needs_update;
+}
+
 __printf_2_3 static void print_in_bar(int color, const char *fmt,...)
 {
 	char *msg;
@@ -310,7 +324,7 @@ __printf_2_3 static void print_in_bar(int color, const char *fmt,...)
 	wmove(in.win, 0, 0);
 	align_str(in.win, msg, get_num_cols(&in), LEFT);
 	free(msg);
-	wrefresh(in.win);
+	refresh_window(&in);
 }
 
 static void print_status_bar(void)
@@ -406,7 +420,7 @@ static void redraw_bot_win(void)
 		waddstr(bot.win, rbe->msg);
 	}
 out:
-	wrefresh(bot.win);
+	refresh_window(&bot);
 }
 
 static void rb_add_entry(int color, char *msg)
@@ -439,10 +453,8 @@ static void rb_add_entry(int color, char *msg)
 	waddstr(bot.win, msg);
 }
 
-/*
- * print formated output to bot win and refresh
- */
-__printf_2_3 static void outputf(int color, const char* fmt,...)
+/* Print formatted output to bot win and refresh. */
+__printf_2_3 static void outputf(int color, const char *fmt,...)
 {
 	char *msg;
 	va_list ap;
@@ -453,7 +465,7 @@ __printf_2_3 static void outputf(int color, const char* fmt,...)
 	xvasprintf(&msg, fmt, ap);
 	va_end(ap);
 	rb_add_entry(color, msg);
-	wrefresh(bot.win);
+	refresh_window(&bot);
 }
 
 static int add_output_line(char *line, void *data)
@@ -480,37 +492,55 @@ static __printf_2_3 void curses_log(int ll, const char *fmt,...)
 		if (bytes > 0 && msg[bytes - 1] == '\n')
 			msg[bytes - 1] = '\0'; /* cut trailing newline */
 		rb_add_entry(color, msg);
-		wrefresh(bot.win);
+		refresh_window(&bot);
 	} else if (exec_pid <= 0) /* no external command running */
 		vfprintf(stderr, fmt, ap);
 	va_end(ap);
 }
-__printf_2_3 void (*para_log)(int, const char*, ...) = curses_log;
 
+/** The log function of para_gui, always set to curses_log(). */
+__printf_2_3 void (*para_log)(int, const char *, ...) = curses_log;
+
+/* Call endwin() to reset the terminal into non-visual mode. */
 static void shutdown_curses(void)
 {
-	def_prog_mode();
+	/*
+	 * If para_gui received a terminating signal in external mode, the
+	 * terminal can be in an unusable state at this point because the child
+	 * process might not have caught the signal. In this case endwin() has
+	 * already been called and must not be called again. So we first return
+	 * to program mode, then call endwin().
+	 */
+	if (!curses_active())
+		reset_prog_mode();
 	endwin();
 }
 
-/* disable curses, print a message, kill running processes and exit */
-__noreturn __printf_2_3 static void die(int exit_code, const char* fmt, ...)
+/* Disable curses, print a message, kill running processes and exit. */
+__noreturn __printf_2_3 static void die(int exit_code, const char *fmt, ...)
 {
 	va_list argp;
 
+	/* Kill every process in our process group. */
+	para_sigaction(SIGTERM, SIG_IGN);
+	kill(0, SIGTERM);
+	/* Wait up to two seconds for child processes to die. */
+	alarm(2);
+	while (waitpid(0, NULL, 0) >= 0)
+		; /* nothing */
+	alarm(0);
+	/* mousemask() exists only in ncurses */
+#ifdef NCURSES_MOUSE_VERSION
+	mousemask(~(mmask_t)0, NULL); /* Avoid bad terminal state with xterm. */
+#endif
 	shutdown_curses();
 	va_start(argp, fmt);
 	vfprintf(stderr, fmt, argp);
 	va_end(argp);
-	/* kill every process in the process group and exit */
-	para_sigaction(SIGTERM, SIG_IGN);
-	kill(0, SIGTERM);
 	exit(exit_code);
 }
 
-/*
- * Print stat item #i to curses window
- */
+/* Print stat item #i to curses window. */
 static void print_stat_item(int i)
 {
 	char *tmp;
@@ -522,11 +552,10 @@ static void print_stat_item(int i)
 		return;
 	tmp = make_message("%s%s%s", d.prefix, c, d.postfix);
 	wmove(top.win, d.y * top_lines / 100, d.x * COLS / 100);
-	wrefresh(top.win);
 	wattron(top.win, COLOR_PAIR(i + 1));
 	align_str(top.win, tmp, d.len * COLS / 100, d.align);
 	free(tmp);
-	wrefresh(top.win);
+	refresh_window(&top);
 }
 
 static int update_item(int item_num, char *buf)
@@ -537,19 +566,19 @@ static int update_item(int item_num, char *buf)
 	if (buf && buf[0])
 		goto dup;
 	switch (item_num) {
-	case SI_ARTIST:
+	case SI_artist:
 		*c = para_strdup("(artist tag not set)");
 		goto print;
-	case SI_TITLE:
+	case SI_title:
 		*c = para_strdup("(title tag not set)");
 		goto print;
-	case SI_YEAR:
+	case SI_year:
 		*c = para_strdup("????");
 		goto print;
-	case SI_ALBUM:
+	case SI_album:
 		*c = para_strdup("(album tag not set)");
 		goto print;
-	case SI_COMMENT:
+	case SI_comment:
 		*c = para_strdup("(comment tag not set)");
 		goto print;
 	}
@@ -580,29 +609,43 @@ static void clear_all_items(void)
 	}
 }
 
-static void status_pre_select(struct sched *s, struct task *t)
+static void status_pre_select(struct sched *s, void *context)
 {
-	struct status_task *st = container_of(t, struct status_task, task);
+	struct status_task *st = context;
 
 	if (st->fd >= 0)
-		return para_fd_set(st->fd, &s->rfds, &s->max_fileno);
-	sched_request_barrier_or_min_delay(&st->next_exec, s);
+		para_fd_set(st->fd, &s->rfds, &s->max_fileno);
+	if (task_get_notification(st->task) < 0)
+		return sched_min_delay(s);
+	if (st->fd < 0)
+		sched_request_barrier_or_min_delay(&st->next_exec, s);
 }
 
-static int status_post_select(struct sched *s, struct task *t)
+static int status_post_select(struct sched *s, void *context)
 {
-	struct status_task *st = container_of(t, struct status_task, task);
+	struct status_task *st = context;
 	size_t sz;
-	pid_t pid;
 	int ret, ret2;
 
+	ret = task_get_notification(st->task);
+	if (ret == -E_GUI_SIGCHLD && st->pid > 0) {
+		int exit_status;
+		if (waitpid(st->pid, &exit_status, WNOHANG) == st->pid) {
+			st->pid = 0;
+			PARA_ERROR_LOG("stat command exit status: %d",
+				exit_status);
+		}
+	}
 	if (st->fd < 0) {
 		int fds[3] = {0, 1, 0};
+		if (st->pid > 0)
+			return 0;
 		/* Avoid busy loop */
 		if (tv_diff(&st->next_exec, now, NULL) > 0)
 			return 0;
 		st->next_exec.tv_sec = now->tv_sec + 2;
-		ret = para_exec_cmdline_pid(&pid, conf.stat_cmd_arg, fds);
+		ret = para_exec_cmdline_pid(&st->pid,
+			OPT_STRING_VAL(STAT_CMD), fds);
 		if (ret < 0)
 			return 0;
 		ret = mark_fd_nonblocking(fds[1]);
@@ -629,12 +672,13 @@ static int status_post_select(struct sched *s, struct task *t)
 	ret2 = for_each_stat_item(st->buf, st->loaded, update_item);
 	if (ret < 0 || ret2 < 0) {
 		st->loaded = 0;
-		PARA_NOTICE_LOG("closing stat pipe: %s\n", para_strerror(-ret));
+		PARA_NOTICE_LOG("closing stat pipe: %s\n",
+			para_strerror(ret < 0? -ret : -ret2));
 		close(st->fd);
 		st->fd = -1;
 		clear_all_items();
-		free(stat_content[SI_BASENAME]);
-		stat_content[SI_BASENAME] =
+		free(stat_content[SI_basename]);
+		stat_content[SI_basename] =
 			para_strdup("stat command terminated!?");
 		print_all_items();
 		return 0;
@@ -646,9 +690,7 @@ static int status_post_select(struct sched *s, struct task *t)
 	return 0;
 }
 
-/*
- * init all windows
- */
+/* Initialize all windows. */
 static void init_wins(int top_lines)
 {
 	int top_y = 0, bot_y = top_lines + 1, sb_y = LINES - 2,
@@ -656,7 +698,7 @@ static void init_wins(int top_lines)
 	int bot_lines = LINES - top_lines - 3, sb_lines = 1, in_lines = 1,
 		sep_lines = 1;
 
-	assume_default_colors(theme.default_fg, theme.default_bg);
+	assume_default_colors(theme.dflt.fg, theme.dflt.bg);
 	if (top.win) {
 		wresize(top.win, top_lines, COLS);
 		mvwin(top.win, top_y, 0);
@@ -728,16 +770,16 @@ static void init_colors_or_die(void)
 		die(EXIT_FAILURE, "fatal: failed to start colors\n");
 	FOR_EACH_STATUS_ITEM(i)
 		if (theme.data[i].len)
-			init_pair_or_die(i + 1, theme.data[i].fg,
-				theme.data[i].bg);
-	init_pair_or_die(COLOR_STATUSBAR, theme.sb_fg, theme.sb_bg);
-	init_pair_or_die(COLOR_COMMAND, theme.cmd_fg, theme.cmd_bg);
-	init_pair_or_die(COLOR_OUTPUT, theme.output_fg, theme.output_bg);
-	init_pair_or_die(COLOR_MSG, theme.msg_fg, theme.msg_bg);
-	init_pair_or_die(COLOR_ERRMSG, theme.err_msg_fg, theme.err_msg_bg);
-	init_pair_or_die(COLOR_SEPARATOR, theme.sep_fg, theme.sep_bg);
-	init_pair_or_die(COLOR_TOP, theme.default_fg, theme.default_bg);
-	init_pair_or_die(COLOR_BOT, theme.default_fg, theme.default_bg);
+			init_pair_or_die(i + 1, theme.data[i].color.fg,
+				theme.data[i].color.bg);
+	init_pair_or_die(COLOR_STATUSBAR, theme.sb.fg, theme.sb.bg);
+	init_pair_or_die(COLOR_COMMAND, theme.cmd.fg, theme.cmd.bg);
+	init_pair_or_die(COLOR_OUTPUT, theme.output.fg, theme.output.bg);
+	init_pair_or_die(COLOR_MSG, theme.msg.fg, theme.msg.bg);
+	init_pair_or_die(COLOR_ERRMSG, theme.err_msg.fg, theme.err_msg.bg);
+	init_pair_or_die(COLOR_SEPARATOR, theme.sep.fg, theme.sep.bg);
+	init_pair_or_die(COLOR_TOP, theme.dflt.fg, theme.dflt.bg);
+	init_pair_or_die(COLOR_BOT, theme.dflt.fg, theme.dflt.bg);
 }
 
 /* (Re-)initialize the curses library. */
@@ -745,7 +787,7 @@ static void init_curses(void)
 {
 	if (curses_active())
 		return;
-	if (top.win && refresh() == ERR) /* refresh is really needed */
+	if (refresh() == ERR) /* refresh is really needed */
 		die(EXIT_FAILURE, "refresh() failed\n");
 	if (LINES < theme.lines_min || COLS < theme.cols_min)
 		die(EXIT_FAILURE, "Terminal (%dx%d) too small"
@@ -765,23 +807,6 @@ static void init_curses(void)
 	// noecho(); /* don't echo input */
 }
 
-static void check_sigchld(void)
-{
-	int ret;
-	pid_t pid;
-
-reap_next_child:
-	ret = para_reap_child(&pid);
-	if (ret <= 0)
-		return;
-	if (pid == exec_pid) {
-		exec_pid = 0;
-		init_curses();
-		print_in_bar(COLOR_MSG, " ");
-	}
-	goto reap_next_child;
-}
-
 /*
  * This sucker modifies its first argument. *handler and *arg are
  * pointers to 0-terminated strings (inside line). Crap.
@@ -805,12 +830,13 @@ static void check_key_map_args_or_die(void)
 {
 	int i;
 	char *tmp = NULL;
+	const struct lls_opt_result *lor = OPT_RESULT(KEY_MAP);
 
-	for (i = 0; i < conf.key_map_given; ++i) {
+	FOR_EACH_KEY_MAP(i) {
 		char *handler, *arg;
 
 		free(tmp);
-		tmp = para_strdup(conf.key_map_arg[i]);
+		tmp = para_strdup(lls_string_val(i, lor));
 		if (!split_key_map(tmp, &handler, &arg))
 			break;
 		if (strlen(handler) != 1)
@@ -823,68 +849,50 @@ static void check_key_map_args_or_die(void)
 		if (find_cmd_byname(arg) < 0)
 			break;
 	}
-	if (i != conf.key_map_given)
-		die(EXIT_FAILURE, "invalid key map: %s\n", conf.key_map_arg[i]);
+	if (i != OPT_GIVEN(KEY_MAP))
+		die(EXIT_FAILURE, "invalid key map: %s\n",
+			lls_string_val(i, lor));
 	free(tmp);
 }
 
-static void parse_config_file_or_die(bool override)
-{
-	bool err;
-	char *config_file;
-	struct gui_cmdline_parser_params params = {
-		.override = override,
-		.initialize = 0,
-		.check_required = !override,
-		.check_ambiguity = 0,
-		.print_errors = 1,
-	};
-
-	if (conf.config_file_given)
-		config_file = para_strdup(conf.config_file_arg);
-	else {
-		char *home = para_homedir();
-		config_file = make_message("%s/.paraslash/gui.conf", home);
-		free(home);
-	}
-	if (!file_exists(config_file)) {
-		if (!conf.config_file_given)
-			err = false;
-		else {
-			PARA_EMERG_LOG("config file %s does not exist\n",
-				config_file);
-			err = true;
-		}
-		goto out;
+static void parse_config_file_or_die(bool reload)
+{
+	int ret;
+	unsigned flags = MCF_DONT_FREE;
+
+	if (lpr != cmdline_lpr)
+		lls_free_parse_result(lpr, CMD_PTR);
+	lpr = cmdline_lpr;
+	if (reload)
+		flags |= MCF_OVERRIDE;
+	ret = lsu_merge_config_file_options(OPT_STRING_VAL(CONFIG_FILE),
+		"gui.conf", &lpr, CMD_PTR, gui_suite, flags);
+	if (ret < 0) {
+		PARA_EMERG_LOG("failed to parse config file: %s\n",
+			para_strerror(-ret));
+		exit(EXIT_FAILURE);
 	}
-	gui_cmdline_parser_config_file(config_file, &conf, &params);
-	loglevel = get_loglevel_by_name(conf.loglevel_arg);
+	loglevel = OPT_UINT32_VAL(LOGLEVEL);
 	check_key_map_args_or_die();
-	theme_init(conf.theme_arg, &theme);
-	err = false;
-out:
-	free(config_file);
-	if (err)
-		exit(EXIT_FAILURE);
+	theme_init(OPT_STRING_VAL(THEME), &theme);
 }
 
-/* reread configuration, terminate on errors */
+/* Reread configuration, terminate on errors. */
 static void reread_conf(void)
 {
 	/*
-	 * gengetopt might print to stderr and exit on errors. So we have to
-	 * shutdown curses first.
+	 * If the reload of the config file fails, we are about to exit. In
+	 * this case we print the error message to stderr rather than to the
+	 * curses window.  So we have to shutdown curses first.
 	 */
 	shutdown_curses();
-	parse_config_file_or_die(true /* override */);
+	parse_config_file_or_die(true);
 	init_curses();
 	print_in_bar(COLOR_MSG, "config file reloaded\n");
 }
 
-/*
- * React to various signal-related events
- */
-static int signal_post_select(struct sched *s, __a_unused struct task *t)
+/* React to various signal-related events. */
+static int signal_post_select(struct sched *s, __a_unused void *context)
 {
 	int ret = para_next_signal(&s->rfds);
 
@@ -893,8 +901,8 @@ static int signal_post_select(struct sched *s, __a_unused struct task *t)
 	switch (ret) {
 	case SIGTERM:
 		die(EXIT_FAILURE, "only the good die young (caught SIGTERM)\n");
-		return 1;
 	case SIGWINCH:
+		PARA_NOTICE_LOG("got SIGWINCH\n");
 		if (curses_active()) {
 			shutdown_curses();
 			init_curses();
@@ -902,17 +910,13 @@ static int signal_post_select(struct sched *s, __a_unused struct task *t)
 		}
 		return 1;
 	case SIGINT:
-		PARA_WARNING_LOG("caught SIGINT, reset\n");
-		/* Nothing to do. SIGINT killed our child which gets noticed
-		 * by do_select and resets everything.
-		 */
 		return 1;
 	case SIGUSR1:
 		PARA_NOTICE_LOG("got SIGUSR1, rereading configuration\n");
 		reread_conf();
 		return 1;
 	case SIGCHLD:
-		check_sigchld();
+		task_notify_all(s, E_GUI_SIGCHLD);
 		return 1;
 	}
 	return 1;
@@ -927,26 +931,32 @@ static enum exec_status exec_status(void)
 	return EXEC_IDLE;
 }
 
-static void exec_pre_select(struct sched *s, __a_unused struct task *t)
+static void exec_pre_select(struct sched *s, void *context)
 {
-	enum exec_status es = exec_status();
-
-	if (es != EXEC_DCMD)
-		return;
+	struct exec_task *et = context;
 	if (exec_fds[0] >= 0)
 		para_fd_set(exec_fds[0], &s->rfds, &s->max_fileno);
 	if (exec_fds[1] >= 0)
 		para_fd_set(exec_fds[1], &s->rfds, &s->max_fileno);
+	if (task_get_notification(et->task) < 0)
+		sched_min_delay(s);
 }
 
-static int exec_post_select(struct sched *s, struct task *t)
+static int exec_post_select(struct sched *s, void *context)
 {
-	struct exec_task *ct = container_of(t, struct exec_task, task);
+	struct exec_task *ct = context;
 	int i, ret;
-	enum exec_status es = exec_status();
 
-	if (es != EXEC_DCMD)
-		return 0;
+	ret = task_get_notification(ct->task);
+	if (ret == -E_GUI_SIGCHLD && exec_pid > 0) {
+		int exit_status;
+		if (waitpid(exec_pid, &exit_status, WNOHANG) == exec_pid) {
+			exec_pid = 0;
+			init_curses();
+			PARA_INFO_LOG("command exit status: %d", exit_status);
+			print_in_bar(COLOR_MSG, " ");
+		}
+	}
 	for (i = 0; i < 2; i++) {
 		size_t sz;
 		if (exec_fds[i] < 0)
@@ -959,7 +969,7 @@ static int exec_post_select(struct sched *s, struct task *t)
 		ct->cbo[i] = for_each_line(ct->flags[i], ct->command_buf[i],
 			ct->cbo[i], add_output_line, &i);
 		if (sz != ct->cbo[i]) { /* at least one line found */
-			wrefresh(bot.win);
+			refresh_window(&bot);
 			ct->flags[i] = 0;
 		}
 		if (ret < 0 || exec_pid == 0) {
@@ -982,13 +992,15 @@ static int exec_post_select(struct sched *s, struct task *t)
 	return 0;
 }
 
-static void input_pre_select(struct sched *s, __a_unused struct task *t)
+static void input_pre_select(struct sched *s, __a_unused void *context)
 {
 	if (exec_status() != EXEC_XCMD)
 		para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
+	if (window_update_needed())
+		sched_min_delay(s);
 }
 
-/* read from command pipe and print data to bot window */
+/* Read from command pipe and print data to bot window. */
 static void exec_and_display(const char *file_and_args)
 {
 	int ret, fds[3] = {0, 1, 1};
@@ -1022,9 +1034,7 @@ static void exec_para(const char *args)
 	free(file_and_args);
 }
 
-/*
- * shutdown curses and stat pipe before executing external commands
- */
+/* Shutdown curses and stat pipe before executing external commands. */
 static void exec_external(char *file_and_args)
 {
 	int fds[3] = {-1, -1, -1};
@@ -1038,12 +1048,13 @@ static void exec_external(char *file_and_args)
 static void handle_command(int c)
 {
 	int i;
+	const struct lls_opt_result *lor = OPT_RESULT(KEY_MAP);
 
 	/* first check user-defined key bindings */
-	for (i = 0; i < conf.key_map_given; ++i) {
+	FOR_EACH_KEY_MAP(i) {
 		char *tmp, *handler, *arg;
 
-		tmp = para_strdup(conf.key_map_arg[i]);
+		tmp = para_strdup(lls_string_val(i, lor));
 		if (!split_key_map(tmp, &handler, &arg)) {
 			free(tmp);
 			return;
@@ -1077,37 +1088,47 @@ static void handle_command(int c)
 		km_keyname(c));
 }
 
-static int input_post_select(__a_unused struct sched *s, __a_unused struct task *t)
+static int input_post_select(__a_unused struct sched *s,
+		__a_unused void *context)
 {
 	int ret;
 	enum exec_status exs = exec_status();
 
 	if (exs == EXEC_XCMD)
 		return 0;
+	if (window_update_needed()) {
+		if (top.needs_update)
+			assert(wnoutrefresh(top.win) == OK);
+		if (bot.needs_update)
+			assert(wnoutrefresh(bot.win) == OK);
+		if (sep.needs_update)
+			assert(wnoutrefresh(sep.win) == OK);
+		if (sb.needs_update)
+			assert(wnoutrefresh(sb.win) == OK);
+		if (in.needs_update)
+			assert(wnoutrefresh(in.win) == OK);
+		doupdate();
+		top.needs_update = bot.needs_update = sb.needs_update =
+			in.needs_update = sep.needs_update = false;
+	}
 	ret = wgetch(top.win);
-	if (ret == ERR || ret == KEY_RESIZE)
+	if (ret == ERR)
 		return 0;
-	if (exs == EXEC_IDLE) {
-		handle_command(ret);
+	if (ret == KEY_RESIZE) /* already handled in signal_post_select() */
 		return 0;
-	}
-	if (exec_pid != 0)
+	if (exs == EXEC_IDLE)
+		handle_command(ret);
+	else if (exec_pid > 0)
 		kill(exec_pid, SIGTERM);
 	return 0;
 }
 
-static void signal_pre_select(struct sched *s, struct task *t)
-{
-	struct signal_task *st = container_of(t, struct signal_task, task);
-	para_fd_set(st->fd, &s->rfds, &s->max_fileno);
-}
-
 static void print_scroll_msg(void)
 {
 	unsigned lines_total, filled = ringbuffer_filled(bot_win_rb);
 	int first_rbe = first_visible_rbe(&lines_total);
 
-	print_in_bar(COLOR_MSG, "scrolled view: %d-%d/%d\n", filled - first_rbe,
+	print_in_bar(COLOR_MSG, "scrolled view: %u-%u/%u\n", filled - first_rbe,
 		filled - scroll_position, ringbuffer_filled(bot_win_rb));
 }
 
@@ -1201,7 +1222,7 @@ static void com_scroll_down(void)
 	wmove(bot.win, bot_lines - rbe_lines, 0);
 	wattron(bot.win, COLOR_PAIR(rbe->color));
 	waddstr(bot.win, rbe->msg);
-	wrefresh(bot.win);
+	refresh_window(&bot);
 	print_scroll_msg();
 }
 
@@ -1238,7 +1259,7 @@ static void com_scroll_up(void)
 			break;
 		i--;
 	}
-	wrefresh(bot.win);
+	refresh_window(&bot);
 	print_scroll_msg();
 	return;
 err_out:
@@ -1275,9 +1296,10 @@ static void com_reread_conf(void)
 static void com_help(void)
 {
 	int i;
+	const struct lls_opt_result *lor = OPT_RESULT(KEY_MAP);
 
-	for (i = 0; i < conf.key_map_given; ++i) {
-		char *handler, *arg, *tmp = para_strdup(conf.key_map_arg[i]);
+	FOR_EACH_KEY_MAP(i) {
+		char *handler, *arg, *tmp = para_strdup(lls_string_val(i, lor));
 		const char *handler_text = "???", *desc = NULL;
 
 		if (!split_key_map(tmp, &handler, &arg)) {
@@ -1361,77 +1383,121 @@ static void com_prev_theme(void)
 	com_refresh();
 }
 
-__noreturn static void print_help_and_die(void)
-{
-	struct ggo_help h = DEFINE_GGO_HELP(gui);
-	bool d = conf.detailed_help_given;
-
-	ggo_print_help(&h, d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS);
-	exit(0);
-}
-
 static int setup_tasks_and_schedule(void)
 {
-	struct sched sched = {
-		.default_timeout = {
-			.tv_sec = conf.timeout_arg  / 1000,
-			.tv_usec = (conf.timeout_arg % 1000) * 1000,
-		},
-	};
-	struct exec_task exec_task = {
-		.task = {
-			.status = "exec",
-			.pre_select = exec_pre_select,
-			.post_select = exec_post_select,
-		},
-	};
-	struct status_task status_task = {
-		.task = {
-			.status = "status",
-			.pre_select = status_pre_select,
-			.post_select = status_post_select,
-		},
-		.fd = -1
-	};
-	struct input_task input_task = {
-		.task = {
-			.status = "input",
-			.pre_select = input_pre_select,
-			.post_select = input_post_select,
-		},
-	};
-	struct signal_task signal_task = {
-		.task = {
-			.status = "signal",
-			.pre_select = signal_pre_select,
-			.post_select = signal_post_select,
-		},
-	};
-	signal_task.fd = para_signal_init();
+	int ret;
+	struct exec_task exec_task = {.task = NULL};
+	struct status_task status_task = {.fd = -1};
+	struct input_task input_task = {.task = NULL};
+	struct signal_task *signal_task;
+	struct sched sched = {.default_timeout = {.tv_sec = 1}};
+
+	exec_task.task = task_register(&(struct task_info) {
+		.name = "exec",
+		.pre_select = exec_pre_select,
+		.post_select = exec_post_select,
+		.context = &exec_task,
+	}, &sched);
+
+	status_task.task = task_register(&(struct task_info) {
+		.name = "status",
+		.pre_select = status_pre_select,
+		.post_select = status_post_select,
+		.context = &status_task,
+	}, &sched);
+
+	input_task.task = task_register(&(struct task_info) {
+		.name = "input",
+		.pre_select = input_pre_select,
+		.post_select = input_post_select,
+		.context = &input_task,
+	}, &sched);
+
+	signal_task = signal_init_or_die();
 	para_install_sighandler(SIGINT);
 	para_install_sighandler(SIGTERM);
 	para_install_sighandler(SIGCHLD);
-	para_install_sighandler(SIGWINCH);
 	para_install_sighandler(SIGUSR1);
-
-	register_task(&sched, &exec_task.task);
-	register_task(&sched, &status_task.task);
-	register_task(&sched, &input_task.task);
-	register_task(&sched, &signal_task.task);
-	return schedule(&sched);
+	para_install_sighandler(SIGWINCH);
+	signal_task->task = task_register(&(struct task_info) {
+		.name = "signal",
+		.pre_select = signal_pre_select,
+		.post_select = signal_post_select,
+		.context = signal_task,
+	}, &sched);
+	ret = schedule(&sched);
+	sched_shutdown(&sched);
+	signal_shutdown(signal_task);
+	return ret;
+}
+
+static void handle_help_flags(void)
+{
+	char *help;
+
+	if (OPT_GIVEN(DETAILED_HELP))
+		help = lls_long_help(CMD_PTR);
+	else if (OPT_GIVEN(HELP))
+		help = lls_short_help(CMD_PTR);
+	else
+		return;
+	printf("%s\n", help);
+	free(help);
+	exit(EXIT_SUCCESS);
 }
 
+/**
+ * The main function of para_gui.
+ *
+ * \param argc Usual argument count.
+ * \param argv Usual argument vector.
+ *
+ * After initialization para_gui registers the following tasks to the paraslash
+ * scheduler: status, exec, signal, input.
+ *
+ * The status task executes the para_audioc stat command to obtain the status
+ * of para_server and para_audiod, and displays this information in the top
+ * window of para_gui.
+ *
+ * The exec task is responsible for printing the output of the currently
+ * running executable to the bottom window.
+ *
+ * The signal task performs various actions according to signals received. For
+ * example, it reloads the configuration file on SIGUSR1, and it shuts down the
+ * curses system on SIGTERM to restore the terminal settings before exit.
+ *
+ * The input task reads single key strokes from stdin. For each key pressed, it
+ * executes the command handler associated with this key.
+ *
+ * \return \p EXIT_SUCCESS or \p EXIT_FAILURE.
+ */
 int main(int argc, char *argv[])
 {
-	gui_cmdline_parser(argc, argv, &conf); /* exits on errors */
-	loglevel = get_loglevel_by_name(conf.loglevel_arg);
-	version_handle_flag("gui", conf.version_given);
-	if (conf.help_given || conf.detailed_help_given)
-		print_help_and_die();
-	parse_config_file_or_die(false /* override */);
+	int ret;
+	char *errctx;
+
+	ret = lls(lls_parse(argc, argv, CMD_PTR, &cmdline_lpr, &errctx));
+	if (ret < 0)
+		goto out;
+	lpr = cmdline_lpr;
+	loglevel = OPT_UINT32_VAL(LOGLEVEL);
+	version_handle_flag("gui", OPT_GIVEN(VERSION));
+	handle_help_flags();
+	parse_config_file_or_die(false);
 	bot_win_rb = ringbuffer_new(RINGBUFFER_SIZE);
 	setlocale(LC_CTYPE, "");
 	initscr(); /* needed only once, always successful */
 	init_curses();
-	return setup_tasks_and_schedule() < 0? EXIT_FAILURE : EXIT_SUCCESS;
+	ret = setup_tasks_and_schedule();
+out:
+	lls_free_parse_result(lpr, CMD_PTR);
+	if (lpr != cmdline_lpr)
+		lls_free_parse_result(cmdline_lpr, CMD_PTR);
+	if (ret < 0) {
+		if (errctx)
+			PARA_ERROR_LOG("%s\n", errctx);
+		free(errctx);
+		PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+	}
+	return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
 }