vis: defer UI initialization and overhaul argument parsing

Do not initalize curses UI before it is actually needed.
Move vis command line argument parsing logic into main.c.
This fixes `vis -v` output and exit status.

Fix #351

5 files changed, 98 insertions, 91 deletions

diff --git a/main.c b/main.c
index 3b3689b..d1c346e 100644
--- a/main.c
+++ b/main.c
@@ -4,6 +4,9 @@
 #include <wchar.h>
 #include <ctype.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 #include "ui-curses.h"
 #include "vis.h"
@@ -2242,6 +2245,67 @@ int main(int argc, char *argv[]) {
 	sigprocmask(SIG_BLOCK, &blockset, NULL);
 	signal(SIGPIPE, SIG_IGN);
 
+	for (int i = 1; i < argc; i++) {
+		if (argv[i][0] != '-') {
+			continue;
+		} else if (strcmp(argv[i], "-") == 0) {
+			continue;
+		} else if (strcmp(argv[i], "--") == 0) {
+			break;
+		} else if (strcmp(argv[i], "-v") == 0) {
+			puts("vis " VERSION);
+			return 0;
+		} else {
+			fprintf(stderr, "Unknown command option: %s\n", argv[i]);
+			return 1;
+		}
+	}
+
+	char *cmd = NULL;
+	bool end_of_options = false, win_created = false;
+
+	for (int i = 1; i < argc; i++) {
+		if (argv[i][0] == '-' && !end_of_options) {
+			if (strcmp(argv[i], "-") == 0) {
+				if (!vis_window_new_fd(vis, STDOUT_FILENO))
+					vis_die(vis, "Can not create empty buffer\n");
+				ssize_t len = 0;
+				char buf[PIPE_BUF];
+				Text *txt = vis_text(vis);
+				while ((len = read(STDIN_FILENO, buf, sizeof buf)) > 0)
+					text_insert(txt, text_size(txt), buf, len);
+				if (len == -1)
+					vis_die(vis, "Can not read from stdin\n");
+				text_snapshot(txt);
+				int fd = open("/dev/tty", O_RDONLY);
+				if (fd == -1)
+					vis_die(vis, "Can not reopen stdin\n");
+				dup2(fd, STDIN_FILENO);
+				close(fd);
+			} else if (strcmp(argv[i], "--") == 0) {
+				end_of_options = true;
+			}
+			end_of_options = !strcmp(argv[i], "--");
+		} else if (argv[i][0] == '+' && !end_of_options) {
+			cmd = argv[i] + (argv[i][1] == '/' || argv[i][1] == '?');
+		} else if (!vis_window_new(vis, argv[i])) {
+			vis_die(vis, "Can not load `%s': %s\n", argv[i], strerror(errno));
+		} else {
+			win_created = true;
+			if (cmd) {
+				vis_prompt_cmd(vis, cmd);
+				cmd = NULL;
+			}
+		}
+	}
+
+	if (!vis_window(vis) && !win_created) {
+		if (!vis_window_new(vis, NULL))
+			vis_die(vis, "Can not create empty buffer\n");
+		if (cmd)
+			vis_prompt_cmd(vis, cmd);
+	}
+
 	int status = vis_run(vis, argc, argv);
 	vis_free(vis);
 	return status;
diff --git a/ui-curses.c b/ui-curses.c
index b8f1e05..b1972da 100644
--- a/ui-curses.c
+++ b/ui-curses.c
@@ -1048,16 +1048,6 @@ static void ui_info_hide(Ui *ui) {
 	}
 }
 
-static bool ui_init(Ui *ui, Vis *vis) {
-	UiCurses *uic = (UiCurses*)ui;
-	uic->vis = vis;
-	return true;
-}
-
-static bool ui_start(Ui *ui) {
-	return true;
-}
-
 static TermKey *ui_termkey_new(int fd) {
 	TermKey *termkey = termkey_new(fd, TERMKEY_FLAG_UTF8);
 	if (termkey)
@@ -1127,12 +1117,9 @@ static int ui_colors(Ui *ui) {
 	return COLORS;
 }
 
-Ui *ui_curses_new(void) {
-
-	UiCurses *uic = calloc(1, sizeof(UiCurses));
-	Ui *ui = (Ui*)uic;
-	if (!uic)
-		return NULL;
+static bool ui_init(Ui *ui, Vis *vis) {
+	UiCurses *uic = (UiCurses*)ui;
+	uic->vis = vis;
 	tcgetattr(STDERR_FILENO, &uic->tio);
 	if (!(uic->termkey = ui_termkey_new(STDIN_FILENO)))
 		goto err;
@@ -1155,13 +1142,30 @@ Ui *ui_curses_new(void) {
 	keypad(stdscr, TRUE);
 	meta(stdscr, TRUE);
 	curs_set(0);
-	/* needed because we use getch() which implicitly calls refresh() which
-	   would clear the screen (overwrite it with an empty / unused stdscr */
-	refresh();
+
+	struct sigaction sa;
+	sa.sa_flags = 0;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_handler = sigwinch_handler;
+	sigaction(SIGWINCH, &sa, NULL);
+	sigaction(SIGCONT, &sa, NULL);
+
+	ui_resize(ui);
+
+	return true;
+err:
+	ui_die_msg(ui, "Failed to start curses interface\n");
+	return false;
+}
+
+Ui *ui_curses_new(void) {
+
+	Ui *ui = calloc(1, sizeof(UiCurses));
+	if (!ui)
+		return NULL;
 
 	*ui = (Ui) {
 		.init = ui_init,
-		.start = ui_start,
 		.free = ui_curses_free,
 		.termkey_get = ui_termkey_get,
 		.suspend = ui_suspend,
@@ -1183,19 +1187,7 @@ Ui *ui_curses_new(void) {
 		.colors = ui_colors,
 	};
 
-	struct sigaction sa;
-	sa.sa_flags = 0;
-	sigemptyset(&sa.sa_mask);
-	sa.sa_handler = sigwinch_handler;
-	sigaction(SIGWINCH, &sa, NULL);
-	sigaction(SIGCONT, &sa, NULL);
-
-	ui_resize(ui);
-
 	return ui;
-err:
-	ui_curses_free(ui);
-	return NULL;
 }
 
 void ui_curses_free(Ui *ui) {
diff --git a/ui.h b/ui.h
index 26d9050..dd663b8 100644
--- a/ui.h
+++ b/ui.h
@@ -51,7 +51,6 @@ enum UiStyle {
 
 struct Ui {
 	bool (*init)(Ui*, Vis*);
-	bool (*start)(Ui*);
 	void (*free)(Ui*);
 	void (*resize)(Ui*);
 	UiWin* (*window_new)(Ui*, View*, File*, enum UiOption);
diff --git a/vis-core.h b/vis-core.h
index 5dc2a64..6d5d022 100644
--- a/vis-core.h
+++ b/vis-core.h
@@ -172,6 +172,7 @@ struct Vis {
 	Action action_prev;                  /* last operator action used by the repeat (dot) command */
 	Mode *mode;                          /* currently active mode, used to search for keybindings */
 	Mode *mode_prev;                     /* previsouly active user mode */
+	bool initialized;                    /* whether UI and Lua integration has been initialized */
 	volatile bool running;               /* exit main loop once this becomes false */
 	int exit_status;                     /* exit status when terminating main loop */
 	volatile sig_atomic_t cancel_filter; /* abort external command/filter (SIGINT occured) */
diff --git a/vis.c b/vis.c
index d74ecf3..e3ad87e 100644
--- a/vis.c
+++ b/vis.c
@@ -37,6 +37,13 @@ bool vis_event_emit(Vis *vis, enum VisEvents id, ...) {
 	if (!vis->event)
 		return true;
 
+	if (!vis->initialized) {
+		vis->initialized = true;
+		vis->ui->init(vis->ui, vis);
+		if (vis->event && vis->event->vis_init)
+			vis->event->vis_init(vis);
+	}
+
 	va_list ap;
 	va_start(ap, id);
 	bool ret = true;
@@ -493,7 +500,6 @@ Vis *vis_new(Ui *ui, VisEvent *event) {
 	if (!vis)
 		return NULL;
 	vis->ui = ui;
-	vis->ui->init(vis->ui, vis);
 	vis->tabwidth = 8;
 	vis->expandtab = false;
 	vis->registers[VIS_REG_BLACKHOLE].type = REGISTER_BLACKHOLE;
@@ -525,9 +531,6 @@ Vis *vis_new(Ui *ui, VisEvent *event) {
 		goto err;
 	vis->mode_prev = vis->mode = &vis_modes[VIS_MODE_NORMAL];
 	vis->event = event;
-	if (event && event->vis_init)
-		event->vis_init(vis);
-	vis->ui->start(vis->ui);
 	return vis;
 err:
 	vis_free(vis);
@@ -982,62 +985,10 @@ bool vis_signal_handler(Vis *vis, int signum, const siginfo_t *siginfo, const vo
 	return false;
 }
 
-static void vis_args(Vis *vis, int argc, char *argv[]) {
-	char *cmd = NULL;
-	bool end_of_options = false;
-	for (int i = 1; i < argc; i++) {
-		if (argv[i][0] == '-' && !end_of_options) {
-			switch (argv[i][1]) {
-			case '-':
-				end_of_options = true;
-				break;
-			case 'v':
-				vis_die(vis, "vis %s\n", VERSION);
-				break;
-			case '\0':
-				break;
-			default:
-				vis_die(vis, "Unknown command option: %s\n", argv[i]);
-				break;
-			}
-		} else if (argv[i][0] == '+') {
-			cmd = argv[i] + (argv[i][1] == '/' || argv[i][1] == '?');
-		} else if (!vis_window_new(vis, argv[i])) {
-			vis_die(vis, "Can not load `%s': %s\n", argv[i], strerror(errno));
-		} else if (cmd) {
-			vis_prompt_cmd(vis, cmd);
-			cmd = NULL;
-		}
-	}
-
-	if (!vis->windows && vis->running) {
-		if (!strcmp(argv[argc-1], "-")) {
-			if (!vis_window_new_fd(vis, STDOUT_FILENO))
-				vis_die(vis, "Can not create empty buffer\n");
-			ssize_t len = 0;
-			char buf[PIPE_BUF];
-			Text *txt = vis_text(vis);
-			while ((len = read(STDIN_FILENO, buf, sizeof buf)) > 0)
-				text_insert(txt, text_size(txt), buf, len);
-			if (len == -1)
-				vis_die(vis, "Can not read from stdin\n");
-			text_snapshot(txt);
-			int fd = open("/dev/tty", O_RDONLY);
-			if (fd == -1)
-				vis_die(vis, "Can not reopen stdin\n");
-			dup2(fd, STDIN_FILENO);
-			close(fd);
-		} else if (!vis_window_new(vis, NULL)) {
-			vis_die(vis, "Can not create empty buffer\n");
-		}
-		if (cmd)
-			vis_prompt_cmd(vis, cmd);
-	}
-}
-
 int vis_run(Vis *vis, int argc, char *argv[]) {
+	if (!vis->windows)
+		return EXIT_SUCCESS;
 	vis->running = true;
-	vis_args(vis, argc, argv);
 
 	vis_event_emit(vis, VIS_EVENT_START);