1 /* TUI support I/O functions.
3 Copyright (C) 1998-2016 Free Software Foundation, Inc.
5 Contributed by Hewlett-Packard Company.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "event-loop.h"
25 #include "event-top.h"
29 #include "tui/tui-data.h"
30 #include "tui/tui-io.h"
31 #include "tui/tui-command.h"
32 #include "tui/tui-win.h"
33 #include "tui/tui-wingeneral.h"
34 #include "tui/tui-file.h"
35 #include "tui/tui-out.h"
40 #include "filestuff.h"
41 #include "completer.h"
42 #include "gdb_curses.h"
44 /* This redefines CTRL if it is not already defined, so it must come
45 after terminal state releated include files like <term.h> and
47 #include "readline/readline.h"
50 key_is_start_sequence (int ch)
56 key_is_end_sequence (int ch)
62 key_is_backspace (int ch)
67 /* Use definition from readline 4.3. */
69 #define CTRL_CHAR(c) \
70 ((c) < control_character_threshold && (((c) & 0x80) == 0))
72 /* This file controls the IO interactions between gdb and curses.
73 When the TUI is enabled, gdb has two modes a curses and a standard
76 In curses mode, the gdb outputs are made in a curses command
77 window. For this, the gdb_stdout and gdb_stderr are redirected to
78 the specific ui_file implemented by TUI. The output is handled by
79 tui_puts(). The input is also controlled by curses with
80 tui_getc(). The readline library uses this function to get its
81 input. Several readline hooks are installed to redirect readline
82 output to the TUI (see also the note below).
84 In normal mode, the gdb outputs are restored to their origin, that
85 is as if TUI is not used. Readline also uses its original getc()
88 Note SCz/2001-07-21: the current readline is not clean in its
89 management of the output. Even if we install a redisplay handler,
90 it sometimes writes on a stdout file. It is important to redirect
91 every output produced by readline, otherwise the curses window will
92 be garbled. This is implemented with a pipe that TUI reads and
93 readline writes to. A gdb input handler is created so that reading
94 the pipe is handled automatically. This will probably not work on
95 non-Unix platforms. The best fix is to make readline clean enougth
96 so that is never write on stdout.
98 Note SCz/2002-09-01: we now use more readline hooks and it seems
99 that with them we don't need the pipe anymore (verified by creating
100 the pipe and closing its end so that write causes a SIGPIPE). The
101 old pipe code is still there and can be conditionally removed by
102 #undef TUI_USE_PIPE_FOR_READLINE. */
104 /* For gdb 5.3, prefer to continue the pipe hack as a backup wheel. */
106 #define TUI_USE_PIPE_FOR_READLINE
108 /* #undef TUI_USE_PIPE_FOR_READLINE */
110 /* TUI output files. */
111 static struct ui_file *tui_stdout;
112 static struct ui_file *tui_stderr;
113 struct ui_out *tui_out;
115 /* GDB output files in non-curses mode. */
116 static struct ui_file *tui_old_stdout;
117 static struct ui_file *tui_old_stderr;
118 cli_ui_out *tui_old_uiout;
120 /* Readline previous hooks. */
121 static rl_getc_func_t *tui_old_rl_getc_function;
122 static rl_voidfunc_t *tui_old_rl_redisplay_function;
123 static rl_vintfunc_t *tui_old_rl_prep_terminal;
124 static rl_voidfunc_t *tui_old_rl_deprep_terminal;
125 static rl_compdisp_func_t *tui_old_rl_display_matches_hook;
126 static int tui_old_rl_echoing_p;
128 /* Readline output stream.
129 Should be removed when readline is clean. */
130 static FILE *tui_rl_outstream;
131 static FILE *tui_old_rl_outstream;
132 #ifdef TUI_USE_PIPE_FOR_READLINE
133 static int tui_readline_pipe[2];
136 /* The last gdb prompt that was registered in readline.
137 This may be the main gdb prompt or a secondary prompt. */
138 static char *tui_rl_saved_prompt;
150 /* Print the string in the curses command window.
151 The output is buffered. It is up to the caller to refresh the screen
155 tui_puts (const char *string)
157 static int tui_skip_line = -1;
161 w = TUI_CMD_WIN->generic.handle;
162 while ((c = *string++) != 0)
164 /* Catch annotation and discard them. We need two \032 and
165 discard until a \n is seen. */
170 else if (tui_skip_line != 1)
173 /* Expand TABs, since ncurses on MS-Windows doesn't. */
183 } while ((col % 8) != 0);
191 TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
194 /* Readline callback.
195 Redisplay the command line with its prompt after readline has
196 changed the edited text. */
198 tui_redisplay_readline (void)
210 /* Detect when we temporarily left SingleKey and now the readline
211 edit buffer is empty, automatically restore the SingleKey
212 mode. The restore must only be done if the command has finished.
213 The command could call prompt_for_continue and we must not
214 restore SingleKey so that the prompt and normal keymap are used. */
215 if (tui_current_key_mode == TUI_ONE_COMMAND_MODE && rl_end == 0
216 && !gdb_in_secondary_prompt_p (current_ui))
217 tui_set_key_mode (TUI_SINGLE_KEY_MODE);
219 if (tui_current_key_mode == TUI_SINGLE_KEY_MODE)
222 prompt = tui_rl_saved_prompt;
226 w = TUI_CMD_WIN->generic.handle;
227 start_line = TUI_CMD_WIN->detail.command_info.start_line;
228 wmove (w, start_line, 0);
231 for (in = 0; prompt && prompt[in]; in++)
233 waddch (w, prompt[in]);
239 for (in = 0; in <= rl_end; in++)
245 getyx (w, c_line, c_pos);
251 c = (unsigned char) rl_line_buffer[in];
252 if (CTRL_CHAR (c) || c == RUBOUT)
255 waddch (w, CTRL_CHAR (c) ? UNCTRL (c) : '?');
259 /* Expand TABs, since ncurses on MS-Windows doesn't. */
265 } while ((col % 8) != 0);
272 TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
279 TUI_CMD_WIN->detail.command_info.start_line = getcury (w);
281 wmove (w, c_line, c_pos);
282 TUI_CMD_WIN->detail.command_info.start_line -= height - 1;
288 /* Readline callback to prepare the terminal. It is called once each
289 time we enter readline. Terminal is already setup in curses
292 tui_prep_terminal (int notused1)
294 /* Save the prompt registered in readline to correctly display it.
295 (we can't use gdb_prompt() due to secondary prompts and can't use
296 rl_prompt because it points to an alloca buffer). */
297 xfree (tui_rl_saved_prompt);
298 tui_rl_saved_prompt = rl_prompt != NULL ? xstrdup (rl_prompt) : NULL;
301 /* Readline callback to restore the terminal. It is called once each
302 time we leave readline. There is nothing to do in curses mode. */
304 tui_deprep_terminal (void)
308 #ifdef TUI_USE_PIPE_FOR_READLINE
309 /* Read readline output pipe and feed the command window with it.
310 Should be removed when readline is clean. */
312 tui_readline_output (int error, gdb_client_data data)
317 size = read (tui_readline_pipe[0], buf, sizeof (buf) - 1);
318 if (size > 0 && tui_active)
326 /* TUI version of displayer.crlf. */
329 tui_mld_crlf (const struct match_list_displayer *displayer)
334 /* TUI version of displayer.putch. */
337 tui_mld_putch (const struct match_list_displayer *displayer, int ch)
342 /* TUI version of displayer.puts. */
345 tui_mld_puts (const struct match_list_displayer *displayer, const char *s)
350 /* TUI version of displayer.flush. */
353 tui_mld_flush (const struct match_list_displayer *displayer)
355 wrefresh (TUI_CMD_WIN->generic.handle);
358 /* TUI version of displayer.erase_entire_line. */
361 tui_mld_erase_entire_line (const struct match_list_displayer *displayer)
363 WINDOW *w = TUI_CMD_WIN->generic.handle;
364 int cur_y = getcury (w);
371 /* TUI version of displayer.beep. */
374 tui_mld_beep (const struct match_list_displayer *displayer)
379 /* Helper function for tui_mld_read_key.
380 This temporarily replaces tui_getc for use during tab-completion
381 match list display. */
384 tui_mld_getc (FILE *fp)
386 WINDOW *w = TUI_CMD_WIN->generic.handle;
392 /* TUI version of displayer.read_key. */
395 tui_mld_read_key (const struct match_list_displayer *displayer)
397 rl_getc_func_t *prev = rl_getc_function;
400 /* We can't use tui_getc as we need NEWLINE to not get emitted. */
401 rl_getc_function = tui_mld_getc;
403 rl_getc_function = prev;
407 /* TUI version of rl_completion_display_matches_hook.
408 See gdb_display_match_list for a description of the arguments. */
411 tui_rl_display_match_list (char **matches, int len, int max)
413 struct match_list_displayer displayer;
415 rl_get_screen_size (&displayer.height, &displayer.width);
416 displayer.crlf = tui_mld_crlf;
417 displayer.putch = tui_mld_putch;
418 displayer.puts = tui_mld_puts;
419 displayer.flush = tui_mld_flush;
420 displayer.erase_entire_line = tui_mld_erase_entire_line;
421 displayer.beep = tui_mld_beep;
422 displayer.read_key = tui_mld_read_key;
424 gdb_display_match_list (matches, len, max, &displayer);
427 /* Setup the IO for curses or non-curses mode.
428 - In non-curses mode, readline and gdb use the standard input and
429 standard output/error directly.
430 - In curses mode, the standard output/error is controlled by TUI
431 with the tui_stdout and tui_stderr. The output is redirected in
432 the curses command window. Several readline callbacks are installed
433 so that readline asks for its input to the curses command window
436 tui_setup_io (int mode)
438 extern int _rl_echoing_p;
442 /* Redirect readline to TUI. */
443 tui_old_rl_redisplay_function = rl_redisplay_function;
444 tui_old_rl_deprep_terminal = rl_deprep_term_function;
445 tui_old_rl_prep_terminal = rl_prep_term_function;
446 tui_old_rl_getc_function = rl_getc_function;
447 tui_old_rl_display_matches_hook = rl_completion_display_matches_hook;
448 tui_old_rl_outstream = rl_outstream;
449 tui_old_rl_echoing_p = _rl_echoing_p;
450 rl_redisplay_function = tui_redisplay_readline;
451 rl_deprep_term_function = tui_deprep_terminal;
452 rl_prep_term_function = tui_prep_terminal;
453 rl_getc_function = tui_getc;
455 rl_outstream = tui_rl_outstream;
457 rl_completion_display_matches_hook = tui_rl_display_match_list;
458 rl_already_prompted = 0;
460 /* Keep track of previous gdb output. */
461 tui_old_stdout = gdb_stdout;
462 tui_old_stderr = gdb_stderr;
463 tui_old_uiout = dynamic_cast<cli_ui_out *> (current_uiout);
464 gdb_assert (tui_old_uiout != nullptr);
466 /* Reconfigure gdb output. */
467 gdb_stdout = tui_stdout;
468 gdb_stderr = tui_stderr;
469 gdb_stdlog = gdb_stdout; /* for moment */
470 gdb_stdtarg = gdb_stderr; /* for moment */
471 gdb_stdtargerr = gdb_stderr; /* for moment */
472 current_uiout = tui_out;
474 /* Save tty for SIGCONT. */
479 /* Restore gdb output. */
480 gdb_stdout = tui_old_stdout;
481 gdb_stderr = tui_old_stderr;
482 gdb_stdlog = gdb_stdout; /* for moment */
483 gdb_stdtarg = gdb_stderr; /* for moment */
484 gdb_stdtargerr = gdb_stderr; /* for moment */
485 current_uiout = tui_old_uiout;
487 /* Restore readline. */
488 rl_redisplay_function = tui_old_rl_redisplay_function;
489 rl_deprep_term_function = tui_old_rl_deprep_terminal;
490 rl_prep_term_function = tui_old_rl_prep_terminal;
491 rl_getc_function = tui_old_rl_getc_function;
492 rl_completion_display_matches_hook = tui_old_rl_display_matches_hook;
493 rl_outstream = tui_old_rl_outstream;
494 _rl_echoing_p = tui_old_rl_echoing_p;
495 rl_already_prompted = 0;
497 /* Save tty for SIGCONT. */
503 /* Catch SIGCONT to restore the terminal and refresh the screen. */
505 tui_cont_sig (int sig)
509 /* Restore the terminal setting because another process (shell)
510 might have changed it. */
513 /* Force a refresh of the screen. */
514 tui_refresh_all_win ();
516 wrefresh (TUI_CMD_WIN->generic.handle);
518 signal (sig, tui_cont_sig);
522 /* Initialize the IO for gdb in curses mode. */
524 tui_initialize_io (void)
527 signal (SIGCONT, tui_cont_sig);
530 /* Create tui output streams. */
531 tui_stdout = tui_fileopen (stdout);
532 tui_stderr = tui_fileopen (stderr);
533 tui_out = tui_out_new (tui_stdout);
535 /* Create the default UI. */
536 tui_old_uiout = cli_out_new (gdb_stdout);
538 #ifdef TUI_USE_PIPE_FOR_READLINE
539 /* Temporary solution for readline writing to stdout: redirect
540 readline output in a pipe, read that pipe and output the content
541 in the curses command window. */
542 if (gdb_pipe_cloexec (tui_readline_pipe) != 0)
543 error (_("Cannot create pipe for readline"));
545 tui_rl_outstream = fdopen (tui_readline_pipe[1], "w");
546 if (tui_rl_outstream == 0)
547 error (_("Cannot redirect readline output"));
549 setvbuf (tui_rl_outstream, (char*) NULL, _IOLBF, 0);
552 (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NONBLOCK);
555 (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NDELAY);
558 add_file_handler (tui_readline_pipe[0], tui_readline_output, 0);
560 tui_rl_outstream = stdout;
564 /* Get a character from the command window. This is called from the
572 w = TUI_CMD_WIN->generic.handle;
574 #ifdef TUI_USE_PIPE_FOR_READLINE
575 /* Flush readline output. */
576 tui_readline_output (0, 0);
581 /* The \n must be echoed because it will not be printed by
585 /* When hitting return with an empty input, gdb executes the last
586 command. If we emit a newline, this fills up the command window
587 with empty lines with gdb prompt at beginning. Instead of that,
588 stay on the same line but provide a visual effect to show the
589 user we recognized the command. */
590 if (rl_end == 0 && !gdb_in_secondary_prompt_p (current_ui))
592 wmove (w, getcury (w), 0);
594 /* Clear the line. This will blink the gdb prompt since
595 it will be redrawn at the same line. */
602 /* Move cursor to the end of the command line before emitting the
603 newline. We need to do so because when ncurses outputs a newline
604 it truncates any text that appears past the end of the cursor. */
607 px += rl_end - rl_point;
608 py += px / TUI_CMD_WIN->generic.width;
609 px %= TUI_CMD_WIN->generic.width;
615 /* Handle prev/next/up/down here. */
616 ch = tui_dispatch_ctrl_char (ch);
618 if (ch == KEY_BACKSPACE)
621 if (current_ui->command_editing && key_is_start_sequence (ch))
626 ch_pending = wgetch (w);
629 /* If we have pending input following a start sequence, call the stdin
630 event handler again because ncurses may have already read and stored
631 the input into its internal buffer, meaning that we won't get an stdin
632 event for it. If we don't compensate for this missed stdin event, key
633 sequences as Alt_F (^[f) will not behave promptly.
635 (We only compensates for the missed 2nd byte of a key sequence because
636 2-byte sequences are by far the most commonly used. ncurses may have
637 buffered a larger, 3+-byte key sequence though it remains to be seen
638 whether it is useful to compensate for all the bytes of such
640 if (ch_pending != ERR)
642 ungetch (ch_pending);
643 call_stdin_event_handler_again_p = 1;
650 /* Utility function to expand TABs in a STRING into spaces. STRING
651 will be displayed starting at column COL, and is assumed to include
652 no newlines. The returned expanded string is malloc'ed. */
655 tui_expand_tabs (const char *string, int col)
661 /* 1. How many additional characters do we need? */
662 for (ncol = col, n_adjust = 0, s = string; s; )
664 s = strpbrk (s, "\t");
667 ncol += (s - string) + n_adjust;
668 /* Adjustment for the next tab stop, minus one for the TAB
669 we replace with spaces. */
670 n_adjust += 8 - (ncol % 8) - 1;
675 /* Allocate the copy. */
676 ret = q = (char *) xmalloc (strlen (string) + n_adjust + 1);
678 /* 2. Copy the original string while replacing TABs with spaces. */
679 for (ncol = col, s = string; s; )
681 const char *s1 = strpbrk (s, "\t");
686 strncpy (q, s, s1 - s);
693 } while ((ncol % 8) != 0);