1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
3 This file is part of systemd.
5 Copyright (C) 2014 David Herrmann <dh.herrmann@gmail.com>
7 systemd is free software; you can redistribute it and/or modify it
8 under the terms of the GNU Lesser General Public License as published by
9 the Free Software Foundation; either version 2.1 of the License, or
10 (at your option) any later version.
12 systemd is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public License
18 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 * Stacked Terminal-Emulator
23 * This is an interactive test of the term_screen implementation. It runs a
24 * fully-fletched terminal-emulator inside of a parent TTY. That is, instead of
25 * rendering the terminal as X11-window, it renders it as sub-window in the
26 * parent TTY. Think of this like what "GNU-screen" does.
36 #include <sys/ioctl.h>
42 #include "term-internal.h"
45 typedef struct Output Output;
46 typedef struct Terminal Terminal;
52 unsigned int in_width;
53 unsigned int in_height;
54 unsigned int cursor_x;
55 unsigned int cursor_y;
66 sd_event_source *frame_timer;
74 struct termios saved_in_attr;
75 struct termios saved_out_attr;
80 bool is_scheduled : 1;
89 #define BORDER_HORIZ "\xe2\x94\x81"
90 #define BORDER_VERT "\xe2\x94\x83"
91 #define BORDER_VERT_RIGHT "\xe2\x94\xa3"
92 #define BORDER_VERT_LEFT "\xe2\x94\xab"
93 #define BORDER_DOWN_RIGHT "\xe2\x94\x8f"
94 #define BORDER_DOWN_LEFT "\xe2\x94\x93"
95 #define BORDER_UP_RIGHT "\xe2\x94\x97"
96 #define BORDER_UP_LEFT "\xe2\x94\x9b"
98 static int output_winch(Output *o) {
99 struct winsize wsz = { };
102 assert_return(o, -EINVAL);
104 r = ioctl(o->fd, TIOCGWINSZ, &wsz);
106 log_error("error: cannot read window-size: %m");
110 if (wsz.ws_col != o->width || wsz.ws_row != o->height) {
111 o->width = wsz.ws_col;
112 o->height = wsz.ws_row;
113 o->in_width = MAX(o->width, 2U) - 2;
114 o->in_height = MAX(o->height, 6U) - 6;
121 static int output_flush(Output *o) {
127 len = loop_write(o->fd, o->obuf, o->n_obuf, false);
129 log_error("error: cannot write to TTY (%zd): %s", len, strerror(-len));
138 static int output_write(Output *o, const void *buf, size_t size) {
142 assert_return(o, -EINVAL);
143 assert_return(buf || size < 1, -EINVAL);
148 if (o->n_obuf + size > o->n_obuf && o->n_obuf + size <= sizeof(o->obuf)) {
149 memcpy(o->obuf + o->n_obuf, buf, size);
158 len = loop_write(o->fd, buf, size, false);
160 log_error("error: cannot write to TTY (%zd): %s", len, strerror(-len));
168 static int output_vnprintf(Output *o, size_t max, const char *format, va_list args) {
172 assert_return(o, -EINVAL);
173 assert_return(format, -EINVAL);
174 assert_return(max <= sizeof(buf), -EINVAL);
176 r = vsnprintf(buf, max, format, args);
177 if (r > (ssize_t)max)
180 return output_write(o, buf, r);
184 static int output_nprintf(Output *o, size_t max, const char *format, ...) {
188 va_start(args, format);
189 r = output_vnprintf(o, max, format, args);
196 static int output_vprintf(Output *o, const char *format, va_list args) {
200 assert_return(o, -EINVAL);
201 assert_return(format, -EINVAL);
203 r = vsnprintf(buf, sizeof(buf), format, args);
205 assert_return(r < (ssize_t)sizeof(buf), -ENOBUFS);
207 return output_write(o, buf, r);
211 static int output_printf(Output *o, const char *format, ...) {
215 va_start(args, format);
216 r = output_vprintf(o, format, args);
222 static int output_move_to(Output *o, unsigned int x, unsigned int y) {
225 assert_return(o, -EINVAL);
227 /* force the \e[H code as o->cursor_x/y might be out-of-date */
229 r = output_printf(o, "\e[%u;%uH", y + 1, x + 1);
238 static int output_print_line(Output *o, size_t len) {
240 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
241 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
242 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
243 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
244 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
245 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ
246 BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ BORDER_HORIZ;
247 const size_t max = (sizeof(line) - 1) / (sizeof(BORDER_HORIZ) - 1);
251 assert_return(o, -EINVAL);
253 for ( ; len > 0; len -= i) {
254 i = (len > max) ? max : len;
255 r = output_write(o, line, i * (sizeof(BORDER_HORIZ) - 1));
264 static int output_frame_printl(Output *o, const char *format, ...) {
272 if (o->cursor_y < 3 || o->cursor_y >= o->height - 3)
275 va_start(args, format);
276 r = output_vnprintf(o, o->width - 2, format, args);
282 return output_move_to(o, 1, o->cursor_y + 1);
285 static Output *output_free(Output *o) {
289 /* disable alternate screen buffer */
290 output_printf(o, "\e[?1049l");
293 /* o->fd is owned by the caller */
299 static int output_new(Output **out, int fd) {
303 assert_return(out, -EINVAL);
315 /* enable alternate screen buffer */
316 r = output_printf(o, "\e[?1049h");
332 static void output_draw_frame(Output *o) {
337 /* print header-frame */
339 output_printf(o, BORDER_DOWN_RIGHT);
340 output_print_line(o, o->width - 2);
341 output_printf(o, BORDER_DOWN_LEFT
344 "\e[2;%uH" /* cursor-position: 2/x */
349 output_print_line(o, o->width - 2);
350 output_printf(o, BORDER_VERT_LEFT
353 /* print body-frame */
355 for (i = 0; i < o->in_height; ++i) {
356 output_printf(o, BORDER_VERT
357 "\e[%u;%uH" /* cursor-position: 2/x */
363 /* print footer-frame */
365 output_printf(o, BORDER_VERT_RIGHT);
366 output_print_line(o, o->width - 2);
367 output_printf(o, BORDER_VERT_LEFT
370 "\e[%u;%uH" /* cursor-position: 2/x */
374 o->height - 1, o->width);
375 output_print_line(o, o->width - 2);
376 output_printf(o, BORDER_UP_LEFT);
378 /* print header/footer text */
380 output_printf(o, "\e[2;3H");
381 output_nprintf(o, o->width - 4, "systemd - embedded terminal emulator");
382 output_printf(o, "\e[%u;3H", o->height - 1);
383 output_nprintf(o, o->width - 4, "press ^C to enter menu");
386 static void output_draw_menu(Output *o) {
389 output_frame_printl(o, "%s", "");
390 output_frame_printl(o, " Menu: (the following keys are recognized)");
391 output_frame_printl(o, " q: quit");
392 output_frame_printl(o, " ^C: send ^C to the PTY");
395 static int output_draw_cell_fn(term_screen *screen,
399 const term_attr *attr,
402 unsigned int ch_width) {
403 Output *o = userdata;
407 if (x >= o->in_width || y >= o->in_height)
410 if (x == 0 && y != 0)
411 output_printf(o, "\e[m\r\n" BORDER_VERT);
413 switch (attr->fg.ccode) {
414 case TERM_CCODE_DEFAULT:
415 output_printf(o, "\e[39m");
418 output_printf(o, "\e[38;5;%um", attr->fg.c256);
421 output_printf(o, "\e[38;2;%u;%u;%um", attr->fg.red, attr->fg.green, attr->fg.blue);
423 case TERM_CCODE_BLACK ... TERM_CCODE_WHITE:
425 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_BLACK + 90);
427 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_BLACK + 30);
429 case TERM_CCODE_LIGHT_BLACK ... TERM_CCODE_LIGHT_WHITE:
430 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_LIGHT_BLACK + 90);
434 switch (attr->bg.ccode) {
435 case TERM_CCODE_DEFAULT:
436 output_printf(o, "\e[49m");
439 output_printf(o, "\e[48;5;%um", attr->bg.c256);
442 output_printf(o, "\e[48;2;%u;%u;%um", attr->bg.red, attr->bg.green, attr->bg.blue);
444 case TERM_CCODE_BLACK ... TERM_CCODE_WHITE:
445 output_printf(o, "\e[%um", attr->bg.ccode - TERM_CCODE_BLACK + 40);
447 case TERM_CCODE_LIGHT_BLACK ... TERM_CCODE_LIGHT_WHITE:
448 output_printf(o, "\e[%um", attr->bg.ccode - TERM_CCODE_LIGHT_BLACK + 100);
452 output_printf(o, "\e[%u;%u;%u;%u;%u;%um",
454 attr->italic ? 3 : 23,
455 attr->underline ? 4 : 24,
456 attr->inverse ? 7 : 27,
457 attr->blink ? 5 : 25,
458 attr->hidden ? 8 : 28);
461 output_printf(o, " ");
463 for (k = 0; k < n_ch; ++k) {
464 ulen = term_utf8_encode(utf8, ch[k]);
465 output_write(o, utf8, ulen);
472 static void output_draw_screen(Output *o, term_screen *s) {
476 term_screen_draw(s, output_draw_cell_fn, o, NULL);
478 output_move_to(o, s->cursor_x + 1, s->cursor_y + 3);
479 output_printf(o, "\e[m");
482 static void output_draw(Output *o, bool menu, term_screen *screen) {
486 * This renders the contenst of the terminal. The layout contains a
487 * header, the main body and a footer. Around all areas we draw a
488 * border. It looks something like this:
490 * +----------------------------------------------------+
492 * +----------------------------------------------------+
501 * +----------------------------------------------------+
503 * +----------------------------------------------------+
505 * The body is the part that grows vertically.
507 * We need at least 6 vertical lines to render the screen. This would
508 * leave 0 lines for the body. Therefore, we require 7 lines so there's
509 * at least one body line. Similarly, we need 2 horizontal cells for the
510 * frame, so we require 3.
511 * If the window is too small, we print an error message instead.
514 if (o->in_width < 1 || o->in_height < 1) {
515 output_printf(o, "\e[2J" /* erase-in-display: whole screen */
516 "\e[H"); /* cursor-position: home */
517 output_printf(o, "error: screen too small, need at least 3x7 cells");
523 output_printf(o, "\e[?25l");
525 /* frame-content is contant; only resizes can change it */
526 if (o->resized || o->in_menu != menu) {
527 output_printf(o, "\e[2J" /* erase-in-display: whole screen */
528 "\e[H"); /* cursor-position: home */
529 output_draw_frame(o);
534 /* move cursor to child's position */
535 output_move_to(o, 1, 3);
540 output_draw_screen(o, screen);
543 if (!(screen->flags & TERM_FLAG_HIDE_CURSOR))
544 output_printf(o, "\e[?25h");
547 * Hack: sd-term was not written to support TTY as output-objects, thus
548 * expects callers to use term_screen_feed_keyboard(). However, we
549 * forward TTY input directly. Hence, we're not notified about keypad
550 * changes. Update the related modes djring redraw to keep them at least
553 if (screen->flags & TERM_FLAG_CURSOR_KEYS)
554 output_printf(o, "\e[?1h");
556 output_printf(o, "\e[?1l");
558 if (screen->flags & TERM_FLAG_KEYPAD_MODE)
559 output_printf(o, "\e=");
561 output_printf(o, "\e>");
570 static void terminal_dirty(Terminal *t) {
576 if (t->is_scheduled) {
582 r = sd_event_now(t->event, CLOCK_MONOTONIC, &usec);
585 usec += 16 * USEC_PER_MSEC;
586 r = sd_event_source_set_time(t->frame_timer, usec);
588 r = sd_event_source_set_enabled(t->frame_timer, SD_EVENT_ONESHOT);
590 t->is_scheduled = true;
594 output_draw(t->output, t->is_menu, t->screen);
597 static int terminal_frame_timer_fn(sd_event_source *source, uint64_t usec, void *userdata) {
598 Terminal *t = userdata;
600 t->is_scheduled = false;
607 static int terminal_winch_fn(sd_event_source *source, const struct signalfd_siginfo *ssi, void *userdata) {
608 Terminal *t = userdata;
611 output_winch(t->output);
614 r = pty_resize(t->pty, t->output->in_width, t->output->in_height);
616 log_error("error: pty_resize() (%d): %s", r, strerror(-r));
619 r = term_screen_resize(t->screen, t->output->in_width, t->output->in_height);
621 log_error("error: term_screen_resize() (%d): %s", r, strerror(-r));
628 static int terminal_push_tmp(Terminal *t, uint32_t ucs4) {
635 len = term_utf8_encode(buf, ucs4);
639 r = ring_push(&t->out_ring, buf, len);
646 static int terminal_write_tmp(Terminal *t) {
653 num = ring_peek(&t->out_ring, vec);
658 for (i = 0; i < num; ++i) {
659 r = pty_write(t->pty, vec[i].iov_base, vec[i].iov_len);
661 log_error("error: cannot write to PTY (%d): %s", r, strerror(-r));
667 ring_flush(&t->out_ring);
671 static void terminal_discard_tmp(Terminal *t) {
674 ring_flush(&t->out_ring);
677 static int terminal_menu(Terminal *t, const term_seq *seq) {
679 case TERM_SEQ_IGNORE:
681 case TERM_SEQ_GRAPHIC:
682 switch (seq->terminator) {
684 sd_event_exit(t->event, 0);
689 case TERM_SEQ_CONTROL:
690 switch (seq->terminator) {
692 terminal_push_tmp(t, 0x03);
693 terminal_write_tmp(t);
706 static int terminal_io_fn(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
707 Terminal *t = userdata;
712 len = read(fd, buf, sizeof(buf));
714 if (errno == EAGAIN || errno == EINTR)
717 log_error("error: cannot read from TTY (%d): %m", -errno);
721 for (i = 0; i < len; ++i) {
726 n_str = term_utf8_decode(&t->utf8, &str, buf[i]);
727 for (j = 0; j < n_str; ++j) {
728 type = term_parser_feed(t->parser, &seq, str[j]);
730 log_error("error: term_parser_feed() (%d): %s", type, strerror(-type));
735 r = terminal_push_tmp(t, str[j]);
740 if (type == TERM_SEQ_NONE) {
741 /* We only intercept one-char sequences, so in
742 * case term_parser_feed() couldn't parse a
743 * sequence, it is waiting for more data. We
744 * know it can never be a one-char sequence
745 * then, so we can safely forward the data.
746 * This avoids withholding ESC or other values
747 * that may be one-shot depending on the
749 r = terminal_write_tmp(t);
752 } else if (t->is_menu) {
753 r = terminal_menu(t, seq);
756 } else if (seq->type == TERM_SEQ_CONTROL && seq->terminator == 0x03) { /* ^C opens the menu */
757 terminal_discard_tmp(t);
761 r = terminal_write_tmp(t);
771 static int terminal_pty_fn(Pty *pty, void *userdata, unsigned int event, const void *ptr, size_t size) {
772 Terminal *t = userdata;
777 sd_event_exit(t->event, 0);
780 r = term_screen_feed_text(t->screen, ptr, size);
782 log_error("error: term_screen_feed_text() (%d): %s", r, strerror(-r));
793 static int terminal_write_fn(term_screen *screen, void *userdata, const void *buf, size_t size) {
794 Terminal *t = userdata;
800 r = ring_push(&t->out_ring, buf, size);
807 static int terminal_cmd_fn(term_screen *screen, void *userdata, unsigned int cmd, const term_seq *seq) {
811 static Terminal *terminal_free(Terminal *t) {
815 ring_clear(&t->out_ring);
816 term_screen_unref(t->screen);
817 term_parser_free(t->parser);
818 output_free(t->output);
819 sd_event_source_unref(t->frame_timer);
820 sd_event_unref(t->event);
821 tcsetattr(t->in_fd, TCSANOW, &t->saved_in_attr);
822 tcsetattr(t->out_fd, TCSANOW, &t->saved_out_attr);
828 static int terminal_new(Terminal **out, int in_fd, int out_fd) {
829 struct termios in_attr, out_attr;
833 assert_return(out, -EINVAL);
835 r = tcgetattr(in_fd, &in_attr);
837 log_error("error: tcgetattr() (%d): %m", -errno);
841 r = tcgetattr(out_fd, &out_attr);
843 log_error("error: tcgetattr() (%d): %m", -errno);
847 t = new0(Terminal, 1);
853 memcpy(&t->saved_in_attr, &in_attr, sizeof(in_attr));
854 memcpy(&t->saved_out_attr, &out_attr, sizeof(out_attr));
857 cfmakeraw(&out_attr);
859 r = tcsetattr(t->in_fd, TCSANOW, &in_attr);
861 log_error("error: tcsetattr() (%d): %s", r, strerror(-r));
865 r = tcsetattr(t->out_fd, TCSANOW, &out_attr);
867 log_error("error: tcsetattr() (%d): %s", r, strerror(-r));
871 r = sd_event_default(&t->event);
873 log_error("error: sd_event_default() (%d): %s", r, strerror(-r));
877 r = sigprocmask_many(SIG_BLOCK, SIGINT, SIGQUIT, SIGTERM, SIGWINCH, SIGCHLD, -1);
879 log_error("error: sigprocmask_many() (%d): %s", r, strerror(-r));
883 r = sd_event_add_signal(t->event, NULL, SIGINT, NULL, NULL);
885 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
889 r = sd_event_add_signal(t->event, NULL, SIGQUIT, NULL, NULL);
891 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
895 r = sd_event_add_signal(t->event, NULL, SIGTERM, NULL, NULL);
897 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
901 r = sd_event_add_signal(t->event, NULL, SIGWINCH, terminal_winch_fn, t);
903 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
907 /* force initial redraw on event-loop enter */
909 r = sd_event_add_time(t->event, &t->frame_timer, CLOCK_MONOTONIC, 0, 0, terminal_frame_timer_fn, t);
911 log_error("error: sd_event_add_time() (%d): %s", r, strerror(-r));
915 r = output_new(&t->output, out_fd);
919 r = term_parser_new(&t->parser, true);
923 r = term_screen_new(&t->screen, terminal_write_fn, t, terminal_cmd_fn, t);
927 r = term_screen_set_answerback(t->screen, "systemd-subterm");
931 r = term_screen_resize(t->screen, t->output->in_width, t->output->in_height);
933 log_error("error: term_screen_resize() (%d): %s", r, strerror(-r));
937 r = sd_event_add_io(t->event, NULL, in_fd, EPOLLIN, terminal_io_fn, t);
949 static int terminal_run(Terminal *t) {
952 assert_return(t, -EINVAL);
954 pid = pty_fork(&t->pty, t->event, terminal_pty_fn, t, t->output->in_width, t->output->in_height);
956 log_error("error: cannot fork PTY (%d): %s", pid, strerror(-pid));
958 } else if (pid == 0) {
961 char **argv = (char*[]){
962 (char*)getenv("SHELL") ? : (char*)_PATH_BSHELL,
966 setenv("TERM", "xterm-256color", 1);
967 setenv("COLORTERM", "systemd-subterm", 1);
969 execve(argv[0], argv, environ);
970 log_error("error: cannot exec %s (%d): %m", argv[0], -errno);
976 return sd_event_loop(t->event);
983 int main(int argc, char *argv[]) {
987 r = terminal_new(&t, 0, 1);
997 log_error("error: terminal failed (%d): %s", r, strerror(-r));