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 /* re-enable cursor */
290 output_printf(o, "\e[?25h");
291 /* disable alternate screen buffer */
292 output_printf(o, "\e[?1049l");
295 /* o->fd is owned by the caller */
301 static int output_new(Output **out, int fd) {
305 assert_return(out, -EINVAL);
317 /* enable alternate screen buffer */
318 r = output_printf(o, "\e[?1049h");
322 /* always hide cursor */
323 r = output_printf(o, "\e[?25l");
339 static void output_draw_frame(Output *o) {
344 /* print header-frame */
346 output_printf(o, BORDER_DOWN_RIGHT);
347 output_print_line(o, o->width - 2);
348 output_printf(o, BORDER_DOWN_LEFT
351 "\e[2;%uH" /* cursor-position: 2/x */
356 output_print_line(o, o->width - 2);
357 output_printf(o, BORDER_VERT_LEFT
360 /* print body-frame */
362 for (i = 0; i < o->in_height; ++i) {
363 output_printf(o, BORDER_VERT
364 "\e[%u;%uH" /* cursor-position: 2/x */
370 /* print footer-frame */
372 output_printf(o, BORDER_VERT_RIGHT);
373 output_print_line(o, o->width - 2);
374 output_printf(o, BORDER_VERT_LEFT
377 "\e[%u;%uH" /* cursor-position: 2/x */
381 o->height - 1, o->width);
382 output_print_line(o, o->width - 2);
383 output_printf(o, BORDER_UP_LEFT);
385 /* print header/footer text */
387 output_printf(o, "\e[2;3H");
388 output_nprintf(o, o->width - 4, "systemd - embedded terminal emulator");
389 output_printf(o, "\e[%u;3H", o->height - 1);
390 output_nprintf(o, o->width - 4, "press ^C to enter menu");
393 static void output_draw_menu(Output *o) {
396 output_frame_printl(o, "%s", "");
397 output_frame_printl(o, " Menu: (the following keys are recognized)");
398 output_frame_printl(o, " q: quit");
399 output_frame_printl(o, " ^C: send ^C to the PTY");
402 static int output_draw_cell_fn(term_screen *screen,
406 const term_attr *attr,
409 unsigned int ch_width) {
410 Output *o = userdata;
414 if (x >= o->in_width || y >= o->in_height)
417 if (x == 0 && y != 0)
418 output_printf(o, "\e[m\r\n" BORDER_VERT);
420 switch (attr->fg.ccode) {
421 case TERM_CCODE_DEFAULT:
422 output_printf(o, "\e[39m");
425 output_printf(o, "\e[38;5;%um", attr->fg.c256);
428 output_printf(o, "\e[38;2;%u;%u;%um", attr->fg.red, attr->fg.green, attr->fg.blue);
430 case TERM_CCODE_BLACK ... TERM_CCODE_WHITE:
432 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_BLACK + 90);
434 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_BLACK + 30);
436 case TERM_CCODE_LIGHT_BLACK ... TERM_CCODE_LIGHT_WHITE:
437 output_printf(o, "\e[%um", attr->fg.ccode - TERM_CCODE_LIGHT_BLACK + 90);
441 switch (attr->bg.ccode) {
442 case TERM_CCODE_DEFAULT:
443 output_printf(o, "\e[49m");
446 output_printf(o, "\e[48;5;%um", attr->bg.c256);
449 output_printf(o, "\e[48;2;%u;%u;%um", attr->bg.red, attr->bg.green, attr->bg.blue);
451 case TERM_CCODE_BLACK ... TERM_CCODE_WHITE:
452 output_printf(o, "\e[%um", attr->bg.ccode - TERM_CCODE_BLACK + 40);
454 case TERM_CCODE_LIGHT_BLACK ... TERM_CCODE_LIGHT_WHITE:
455 output_printf(o, "\e[%um", attr->bg.ccode - TERM_CCODE_LIGHT_BLACK + 100);
459 output_printf(o, "\e[%u;%u;%u;%u;%u;%um",
461 attr->italic ? 3 : 23,
462 attr->underline ? 4 : 24,
463 attr->inverse ? 7 : 27,
464 attr->blink ? 5 : 25,
465 attr->hidden ? 8 : 28);
468 output_printf(o, " ");
470 for (k = 0; k < n_ch; ++k) {
471 ulen = term_utf8_encode(utf8, ch[k]);
472 output_write(o, utf8, ulen);
479 static void output_draw_screen(Output *o, term_screen *s) {
483 term_screen_draw(s, output_draw_cell_fn, o, NULL);
485 output_printf(o, "\e[m");
488 static void output_draw(Output *o, bool menu, term_screen *screen) {
492 * This renders the contenst of the terminal. The layout contains a
493 * header, the main body and a footer. Around all areas we draw a
494 * border. It looks something like this:
496 * +----------------------------------------------------+
498 * +----------------------------------------------------+
507 * +----------------------------------------------------+
509 * +----------------------------------------------------+
511 * The body is the part that grows vertically.
513 * We need at least 6 vertical lines to render the screen. This would
514 * leave 0 lines for the body. Therefore, we require 7 lines so there's
515 * at least one body line. Similarly, we need 2 horizontal cells for the
516 * frame, so we require 3.
517 * If the window is too small, we print an error message instead.
520 if (o->in_width < 1 || o->in_height < 1) {
521 output_printf(o, "\e[2J" /* erase-in-display: whole screen */
522 "\e[H"); /* cursor-position: home */
523 output_printf(o, "error: screen too small, need at least 3x7 cells");
529 output_printf(o, "\e[?25l");
531 /* frame-content is contant; only resizes can change it */
532 if (o->resized || o->in_menu != menu) {
533 output_printf(o, "\e[2J" /* erase-in-display: whole screen */
534 "\e[H"); /* cursor-position: home */
535 output_draw_frame(o);
540 /* move cursor to child's position */
541 output_move_to(o, 1, 3);
546 output_draw_screen(o, screen);
549 * Hack: sd-term was not written to support TTY as output-objects, thus
550 * expects callers to use term_screen_feed_keyboard(). However, we
551 * forward TTY input directly. Hence, we're not notified about keypad
552 * changes. Update the related modes djring redraw to keep them at least
555 if (screen->flags & TERM_FLAG_CURSOR_KEYS)
556 output_printf(o, "\e[?1h");
558 output_printf(o, "\e[?1l");
560 if (screen->flags & TERM_FLAG_KEYPAD_MODE)
561 output_printf(o, "\e=");
563 output_printf(o, "\e>");
572 static void terminal_dirty(Terminal *t) {
578 if (t->is_scheduled) {
584 r = sd_event_now(t->event, CLOCK_MONOTONIC, &usec);
587 usec += 16 * USEC_PER_MSEC;
588 r = sd_event_source_set_time(t->frame_timer, usec);
590 r = sd_event_source_set_enabled(t->frame_timer, SD_EVENT_ONESHOT);
592 t->is_scheduled = true;
596 output_draw(t->output, t->is_menu, t->screen);
599 static int terminal_frame_timer_fn(sd_event_source *source, uint64_t usec, void *userdata) {
600 Terminal *t = userdata;
602 t->is_scheduled = false;
609 static int terminal_winch_fn(sd_event_source *source, const struct signalfd_siginfo *ssi, void *userdata) {
610 Terminal *t = userdata;
613 output_winch(t->output);
616 r = pty_resize(t->pty, t->output->in_width, t->output->in_height);
618 log_error("error: pty_resize() (%d): %s", r, strerror(-r));
621 r = term_screen_resize(t->screen, t->output->in_width, t->output->in_height);
623 log_error("error: term_screen_resize() (%d): %s", r, strerror(-r));
630 static int terminal_push_tmp(Terminal *t, uint32_t ucs4) {
637 len = term_utf8_encode(buf, ucs4);
641 r = ring_push(&t->out_ring, buf, len);
648 static int terminal_write_tmp(Terminal *t) {
655 num = ring_peek(&t->out_ring, vec);
660 for (i = 0; i < num; ++i) {
661 r = pty_write(t->pty, vec[i].iov_base, vec[i].iov_len);
663 log_error("error: cannot write to PTY (%d): %s", r, strerror(-r));
669 ring_flush(&t->out_ring);
673 static void terminal_discard_tmp(Terminal *t) {
676 ring_flush(&t->out_ring);
679 static int terminal_menu(Terminal *t, const term_seq *seq) {
681 case TERM_SEQ_IGNORE:
683 case TERM_SEQ_GRAPHIC:
684 switch (seq->terminator) {
686 sd_event_exit(t->event, 0);
691 case TERM_SEQ_CONTROL:
692 switch (seq->terminator) {
694 terminal_push_tmp(t, 0x03);
695 terminal_write_tmp(t);
708 static int terminal_io_fn(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
709 Terminal *t = userdata;
714 len = read(fd, buf, sizeof(buf));
716 if (errno == EAGAIN || errno == EINTR)
719 log_error("error: cannot read from TTY (%d): %m", -errno);
723 for (i = 0; i < len; ++i) {
728 n_str = term_utf8_decode(&t->utf8, &str, buf[i]);
729 for (j = 0; j < n_str; ++j) {
730 type = term_parser_feed(t->parser, &seq, str[j]);
732 log_error("error: term_parser_feed() (%d): %s", type, strerror(-type));
737 r = terminal_push_tmp(t, str[j]);
742 if (type == TERM_SEQ_NONE) {
743 /* We only intercept one-char sequences, so in
744 * case term_parser_feed() couldn't parse a
745 * sequence, it is waiting for more data. We
746 * know it can never be a one-char sequence
747 * then, so we can safely forward the data.
748 * This avoids withholding ESC or other values
749 * that may be one-shot depending on the
751 r = terminal_write_tmp(t);
754 } else if (t->is_menu) {
755 r = terminal_menu(t, seq);
758 } else if (seq->type == TERM_SEQ_CONTROL && seq->terminator == 0x03) { /* ^C opens the menu */
759 terminal_discard_tmp(t);
763 r = terminal_write_tmp(t);
773 static int terminal_pty_fn(Pty *pty, void *userdata, unsigned int event, const void *ptr, size_t size) {
774 Terminal *t = userdata;
779 sd_event_exit(t->event, 0);
782 r = term_screen_feed_text(t->screen, ptr, size);
784 log_error("error: term_screen_feed_text() (%d): %s", r, strerror(-r));
795 static int terminal_write_fn(term_screen *screen, void *userdata, const void *buf, size_t size) {
796 Terminal *t = userdata;
802 r = ring_push(&t->out_ring, buf, size);
809 static int terminal_cmd_fn(term_screen *screen, void *userdata, unsigned int cmd, const term_seq *seq) {
813 static Terminal *terminal_free(Terminal *t) {
817 ring_clear(&t->out_ring);
818 term_screen_unref(t->screen);
819 term_parser_free(t->parser);
820 output_free(t->output);
821 sd_event_source_unref(t->frame_timer);
822 sd_event_unref(t->event);
823 tcsetattr(t->in_fd, TCSANOW, &t->saved_in_attr);
824 tcsetattr(t->out_fd, TCSANOW, &t->saved_out_attr);
830 static int terminal_new(Terminal **out, int in_fd, int out_fd) {
831 struct termios in_attr, out_attr;
835 assert_return(out, -EINVAL);
837 r = tcgetattr(in_fd, &in_attr);
839 log_error("error: tcgetattr() (%d): %m", -errno);
843 r = tcgetattr(out_fd, &out_attr);
845 log_error("error: tcgetattr() (%d): %m", -errno);
849 t = new0(Terminal, 1);
855 memcpy(&t->saved_in_attr, &in_attr, sizeof(in_attr));
856 memcpy(&t->saved_out_attr, &out_attr, sizeof(out_attr));
859 cfmakeraw(&out_attr);
861 r = tcsetattr(t->in_fd, TCSANOW, &in_attr);
863 log_error("error: tcsetattr() (%d): %s", r, strerror(-r));
867 r = tcsetattr(t->out_fd, TCSANOW, &out_attr);
869 log_error("error: tcsetattr() (%d): %s", r, strerror(-r));
873 r = sd_event_default(&t->event);
875 log_error("error: sd_event_default() (%d): %s", r, strerror(-r));
879 r = sigprocmask_many(SIG_BLOCK, SIGINT, SIGQUIT, SIGTERM, SIGWINCH, SIGCHLD, -1);
881 log_error("error: sigprocmask_many() (%d): %s", r, strerror(-r));
885 r = sd_event_add_signal(t->event, NULL, SIGINT, NULL, NULL);
887 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
891 r = sd_event_add_signal(t->event, NULL, SIGQUIT, NULL, NULL);
893 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
897 r = sd_event_add_signal(t->event, NULL, SIGTERM, NULL, NULL);
899 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
903 r = sd_event_add_signal(t->event, NULL, SIGWINCH, terminal_winch_fn, t);
905 log_error("error: sd_event_add_signal() (%d): %s", r, strerror(-r));
909 /* force initial redraw on event-loop enter */
911 r = sd_event_add_time(t->event, &t->frame_timer, CLOCK_MONOTONIC, 0, 0, terminal_frame_timer_fn, t);
913 log_error("error: sd_event_add_time() (%d): %s", r, strerror(-r));
917 r = output_new(&t->output, out_fd);
921 r = term_parser_new(&t->parser, true);
925 r = term_screen_new(&t->screen, terminal_write_fn, t, terminal_cmd_fn, t);
929 r = term_screen_set_answerback(t->screen, "systemd-subterm");
933 r = term_screen_resize(t->screen, t->output->in_width, t->output->in_height);
935 log_error("error: term_screen_resize() (%d): %s", r, strerror(-r));
939 r = sd_event_add_io(t->event, NULL, in_fd, EPOLLIN, terminal_io_fn, t);
951 static int terminal_run(Terminal *t) {
954 assert_return(t, -EINVAL);
956 pid = pty_fork(&t->pty, t->event, terminal_pty_fn, t, t->output->in_width, t->output->in_height);
958 log_error("error: cannot fork PTY (%d): %s", pid, strerror(-pid));
960 } else if (pid == 0) {
963 char **argv = (char*[]){
964 (char*)getenv("SHELL") ? : (char*)_PATH_BSHELL,
968 setenv("TERM", "xterm-256color", 1);
969 setenv("COLORTERM", "systemd-subterm", 1);
971 execve(argv[0], argv, environ);
972 log_error("error: cannot exec %s (%d): %m", argv[0], -errno);
978 return sd_event_loop(t->event);
985 int main(int argc, char *argv[]) {
989 r = terminal_new(&t, 0, 1);
999 log_error("error: terminal failed (%d): %s", r, strerror(-r));