gdb/tui/tuiIO.c

   1 /* TUI support I/O functions.
   2
   3    Copyright 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation,
   4    Inc.
   5
   6    Contributed by Hewlett-Packard Company.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25 #include "defs.h"
  26 #include "terminal.h"
  27 #include "target.h"
  28 #include "event-loop.h"
  29 #include "event-top.h"
  30 #include "command.h"
  31 #include "top.h"
  32 #include "readline/readline.h"
  33 #include "tui.h"
  34 #include "tuiData.h"
  35 #include "tuiIO.h"
  36 #include "tuiCommand.h"
  37 #include "tuiWin.h"
  38 #include "tuiGeneralWin.h"
  39 #include "tui-file.h"
  40 #include "ui-out.h"
  41 #include "cli-out.h"
  42 #include <fcntl.h>
  43 #include <signal.h>
  44 #include <stdio.h>
  45
  46 #ifdef HAVE_NCURSES_H
  47 #include <ncurses.h>
  48 #else
  49 #ifdef HAVE_CURSES_H
  50 #include <curses.h>
  51 #endif
  52 #endif
  53
  54 /* Use definition from readline 4.3.  */
  55 #undef CTRL_CHAR
  56 #define CTRL_CHAR(c) ((c) < control_character_threshold && (((c) & 0x80) == 0))
  57
  58 /* This file controls the IO interactions between gdb and curses.
  59    When the TUI is enabled, gdb has two modes a curses and a standard
  60    mode.
  61
  62    In curses mode, the gdb outputs are made in a curses command window.
  63    For this, the gdb_stdout and gdb_stderr are redirected to the specific
  64    ui_file implemented by TUI.  The output is handled by tui_puts().
  65    The input is also controlled by curses with tui_getc().  The readline
  66    library uses this function to get its input.  Several readline hooks
  67    are installed to redirect readline output to the TUI (see also the
  68    note below).
  69
  70    In normal mode, the gdb outputs are restored to their origin, that
  71    is as if TUI is not used.  Readline also uses its original getc()
  72    function with stdin.
  73
  74    Note SCz/2001-07-21: the current readline is not clean in its management of
  75    the output.  Even if we install a redisplay handler, it sometimes writes on
  76    a stdout file.  It is important to redirect every output produced by
  77    readline, otherwise the curses window will be garbled.  This is implemented
  78    with a pipe that TUI reads and readline writes to.  A gdb input handler
  79    is created so that reading the pipe is handled automatically.
  80    This will probably not work on non-Unix platforms.  The best fix is
  81    to make readline clean enougth so that is never write on stdout.
  82
  83    Note SCz/2002-09-01: we now use more readline hooks and it seems that
  84    with them we don't need the pipe anymore (verified by creating the pipe
  85    and closing its end so that write causes a SIGPIPE).  The old pipe code
  86    is still there and can be conditionally removed by
  87    #undef TUI_USE_PIPE_FOR_READLINE.  */
  88
  89 /* For gdb 5.3, prefer to continue the pipe hack as a backup wheel.  */
  90 #define TUI_USE_PIPE_FOR_READLINE
  91 /*#undef TUI_USE_PIPE_FOR_READLINE*/
  92
  93 /* TUI output files.  */
  94 static struct ui_file *tui_stdout;
  95 static struct ui_file *tui_stderr;
  96 struct ui_out *tui_out;
  97
  98 /* GDB output files in non-curses mode.  */
  99 static struct ui_file *tui_old_stdout;
 100 static struct ui_file *tui_old_stderr;
 101 struct ui_out *tui_old_uiout;
 102
 103 /* Readline previous hooks.  */
 104 static Function *tui_old_rl_getc_function;
 105 static VFunction *tui_old_rl_redisplay_function;
 106 static VFunction *tui_old_rl_prep_terminal;
 107 static VFunction *tui_old_rl_deprep_terminal;
 108 static int tui_old_readline_echoing_p;
 109
 110 /* Readline output stream.
 111    Should be removed when readline is clean.  */
 112 static FILE *tui_rl_outstream;
 113 static FILE *tui_old_rl_outstream;
 114 #ifdef TUI_USE_PIPE_FOR_READLINE
 115 static int tui_readline_pipe[2];
 116 #endif
 117
 118 /* The last gdb prompt that was registered in readline.
 119    This may be the main gdb prompt or a secondary prompt.  */
 120 static char *tui_rl_saved_prompt;
 121
 122 static unsigned int _tuiHandleResizeDuringIO (unsigned int);
 123
 124 static void
 125 tui_putc (char c)
 126 {
 127   char buf[2];
 128
 129   buf[0] = c;
 130   buf[1] = 0;
 131   tui_puts (buf);
 132 }
 133
 134 /* Print the string in the curses command window.  */
 135 void
 136 tui_puts (const char *string)
 137 {
 138   static int tui_skip_line = -1;
 139   char c;
 140   WINDOW *w;
 141
 142   w = cmdWin->generic.handle;
 143   while ((c = *string++) != 0)
 144     {
 145       /* Catch annotation and discard them.  We need two \032 and
 146          discard until a \n is seen.  */
 147       if (c == '\032')
 148         {
 149           tui_skip_line++;
 150         }
 151       else if (tui_skip_line != 1)
 152         {
 153           tui_skip_line = -1;
 154           waddch (w, c);
 155         }
 156       else if (c == '\n')
 157         tui_skip_line = -1;
 158     }
 159   getyx (w, cmdWin->detail.commandInfo.curLine,
 160          cmdWin->detail.commandInfo.curch);
 161   cmdWin->detail.commandInfo.start_line = cmdWin->detail.commandInfo.curLine;
 162
 163   /* We could defer the following.  */
 164   wrefresh (w);
 165   fflush (stdout);
 166 }
 167
 168 /* Readline callback.
 169    Redisplay the command line with its prompt after readline has
 170    changed the edited text.  */
 171 void
 172 tui_redisplay_readline (void)
 173 {
 174   int prev_col;
 175   int height;
 176   int col, line;
 177   int c_pos;
 178   int c_line;
 179   int in;
 180   WINDOW *w;
 181   char *prompt;
 182   int start_line;
 183
 184   /* Detect when we temporarily left SingleKey and now the readline
 185      edit buffer is empty, automatically restore the SingleKey mode.  */
 186   if (tui_current_key_mode == tui_one_command_mode && rl_end == 0)
 187     tui_set_key_mode (tui_single_key_mode);
 188
 189   if (tui_current_key_mode == tui_single_key_mode)
 190     prompt = "";
 191   else
 192     prompt = tui_rl_saved_prompt;
 193
 194   c_pos = -1;
 195   c_line = -1;
 196   w = cmdWin->generic.handle;
 197   start_line = cmdWin->detail.commandInfo.start_line;
 198   wmove (w, start_line, 0);
 199   prev_col = 0;
 200   height = 1;
 201   for (in = 0; prompt && prompt[in]; in++)
 202     {
 203       waddch (w, prompt[in]);
 204       getyx (w, line, col);
 205       if (col < prev_col)
 206         height++;
 207       prev_col = col;
 208     }
 209   for (in = 0; in < rl_end; in++)
 210     {
 211       unsigned char c;
 212
 213       c = (unsigned char) rl_line_buffer[in];
 214       if (in == rl_point)
 215         {
 216           getyx (w, c_line, c_pos);
 217         }
 218
 219       if (CTRL_CHAR (c) || c == RUBOUT)
 220         {
 221           waddch (w, '^');
 222           waddch (w, CTRL_CHAR (c) ? UNCTRL (c) : '?');
 223         }
 224       else
 225         {
 226           waddch (w, c);
 227         }
 228       if (c == '\n')
 229         {
 230           getyx (w, cmdWin->detail.commandInfo.start_line,
 231                  cmdWin->detail.commandInfo.curch);
 232         }
 233       getyx (w, line, col);
 234       if (col < prev_col)
 235         height++;
 236       prev_col = col;
 237     }
 238   wclrtobot (w);
 239   getyx (w, cmdWin->detail.commandInfo.start_line,
 240          cmdWin->detail.commandInfo.curch);
 241   if (c_line >= 0)
 242     {
 243       wmove (w, c_line, c_pos);
 244       cmdWin->detail.commandInfo.curLine = c_line;
 245       cmdWin->detail.commandInfo.curch = c_pos;
 246     }
 247   cmdWin->detail.commandInfo.start_line -= height - 1;
 248
 249   wrefresh (w);
 250   fflush(stdout);
 251 }
 252
 253 /* Readline callback to prepare the terminal.  It is called once
 254    each time we enter readline.  Terminal is already setup in curses mode.  */
 255 static void
 256 tui_prep_terminal (int notused1)
 257 {
 258   /* Save the prompt registered in readline to correctly display it.
 259      (we can't use gdb_prompt() due to secondary prompts and can't use
 260      rl_prompt because it points to an alloca buffer).  */
 261   xfree (tui_rl_saved_prompt);
 262   tui_rl_saved_prompt = xstrdup (rl_prompt);
 263 }
 264
 265 /* Readline callback to restore the terminal.  It is called once
 266    each time we leave readline.  There is nothing to do in curses mode.  */
 267 static void
 268 tui_deprep_terminal (void)
 269 {
 270 }
 271
 272 #ifdef TUI_USE_PIPE_FOR_READLINE
 273 /* Read readline output pipe and feed the command window with it.
 274    Should be removed when readline is clean.  */
 275 static void
 276 tui_readline_output (int code, gdb_client_data data)
 277 {
 278   int size;
 279   char buf[256];
 280
 281   size = read (tui_readline_pipe[0], buf, sizeof (buf) - 1);
 282   if (size > 0 && tui_active)
 283     {
 284       buf[size] = 0;
 285       tui_puts (buf);
 286     }
 287 }
 288 #endif
 289
 290 /* Return the portion of PATHNAME that should be output when listing
 291    possible completions.  If we are hacking filename completion, we
 292    are only interested in the basename, the portion following the
 293    final slash.  Otherwise, we return what we were passed.
 294
 295    Comes from readline/complete.c  */
 296 static char *
 297 printable_part (pathname)
 298      char *pathname;
 299 {
 300   char *temp;
 301
 302   temp = rl_filename_completion_desired ? strrchr (pathname, '/') : (char *)NULL;
 303 #if defined (__MSDOS__)
 304   if (rl_filename_completion_desired && temp == 0 && isalpha (pathname[0]) && pathname[1] == ':')
 305     temp = pathname + 1;
 306 #endif
 307   return (temp ? ++temp : pathname);
 308 }
 309
 310 /* Output TO_PRINT to rl_outstream.  If VISIBLE_STATS is defined and we
 311    are using it, check for and output a single character for `special'
 312    filenames.  Return the number of characters we output. */
 313
 314 #define PUTX(c) \
 315     do { \
 316       if (CTRL_CHAR (c)) \
 317         { \
 318           tui_puts ("^"); \
 319           tui_putc (UNCTRL (c)); \
 320           printed_len += 2; \
 321         } \
 322       else if (c == RUBOUT) \
 323         { \
 324           tui_puts ("^?"); \
 325           printed_len += 2; \
 326         } \
 327       else \
 328         { \
 329           tui_putc (c); \
 330           printed_len++; \
 331         } \
 332     } while (0)
 333
 334 static int
 335 print_filename (to_print, full_pathname)
 336      char *to_print, *full_pathname;
 337 {
 338   int printed_len = 0;
 339   char *s;
 340
 341   for (s = to_print; *s; s++)
 342     {
 343       PUTX (*s);
 344     }
 345   return printed_len;
 346 }
 347
 348 /* The user must press "y" or "n".  Non-zero return means "y" pressed.
 349    Comes from readline/complete.c  */
 350 static int
 351 get_y_or_n ()
 352 {
 353   extern int _rl_abort_internal ();
 354   int c;
 355
 356   for (;;)
 357     {
 358       c = rl_read_key ();
 359       if (c == 'y' || c == 'Y' || c == ' ')
 360         return (1);
 361       if (c == 'n' || c == 'N' || c == RUBOUT)
 362         return (0);
 363       if (c == ABORT_CHAR)
 364         _rl_abort_internal ();
 365       beep ();
 366     }
 367 }
 368
 369 /* A convenience function for displaying a list of strings in
 370    columnar format on readline's output stream.  MATCHES is the list
 371    of strings, in argv format, LEN is the number of strings in MATCHES,
 372    and MAX is the length of the longest string in MATCHES.
 373
 374    Comes from readline/complete.c and modified to write in
 375    the TUI command window using tui_putc/tui_puts.  */
 376 static void
 377 tui_rl_display_match_list (matches, len, max)
 378      char **matches;
 379      int len, max;
 380 {
 381   typedef int QSFUNC (const void *, const void *);
 382   extern int _rl_qsort_string_compare (const void*, const void*);
 383   extern int _rl_print_completions_horizontally;
 384
 385   int count, limit, printed_len;
 386   int i, j, k, l;
 387   char *temp;
 388
 389   /* Screen dimension correspond to the TUI command window.  */
 390   int screenwidth = cmdWin->generic.width;
 391
 392   /* If there are many items, then ask the user if she really wants to
 393      see them all. */
 394   if (len >= rl_completion_query_items)
 395     {
 396       char msg[256];
 397
 398       sprintf (msg, "\nDisplay all %d possibilities? (y or n)", len);
 399       tui_puts (msg);
 400       if (get_y_or_n () == 0)
 401         {
 402           tui_puts ("\n");
 403           return;
 404         }
 405     }
 406
 407   /* How many items of MAX length can we fit in the screen window? */
 408   max += 2;
 409   limit = screenwidth / max;
 410   if (limit != 1 && (limit * max == screenwidth))
 411     limit--;
 412
 413   /* Avoid a possible floating exception.  If max > screenwidth,
 414      limit will be 0 and a divide-by-zero fault will result. */
 415   if (limit == 0)
 416     limit = 1;
 417
 418   /* How many iterations of the printing loop? */
 419   count = (len + (limit - 1)) / limit;
 420
 421   /* Watch out for special case.  If LEN is less than LIMIT, then
 422      just do the inner printing loop.
 423            0 < len <= limit  implies  count = 1. */
 424
 425   /* Sort the items if they are not already sorted. */
 426   if (rl_ignore_completion_duplicates == 0)
 427     qsort (matches + 1, len, sizeof (char *),
 428            (QSFUNC *)_rl_qsort_string_compare);
 429
 430   tui_putc ('\n');
 431
 432   if (_rl_print_completions_horizontally == 0)
 433     {
 434       /* Print the sorted items, up-and-down alphabetically, like ls. */
 435       for (i = 1; i <= count; i++)
 436         {
 437           for (j = 0, l = i; j < limit; j++)
 438             {
 439               if (l > len || matches[l] == 0)
 440                 break;
 441               else
 442                 {
 443                   temp = printable_part (matches[l]);
 444                   printed_len = print_filename (temp, matches[l]);
 445
 446                   if (j + 1 < limit)
 447                     for (k = 0; k < max - printed_len; k++)
 448                       tui_putc (' ');
 449                 }
 450               l += count;
 451             }
 452           tui_putc ('\n');
 453         }
 454     }
 455   else
 456     {
 457       /* Print the sorted items, across alphabetically, like ls -x. */
 458       for (i = 1; matches[i]; i++)
 459         {
 460           temp = printable_part (matches[i]);
 461           printed_len = print_filename (temp, matches[i]);
 462           /* Have we reached the end of this line? */
 463           if (matches[i+1])
 464             {
 465               if (i && (limit > 1) && (i % limit) == 0)
 466                 tui_putc ('\n');
 467               else
 468                 for (k = 0; k < max - printed_len; k++)
 469                   tui_putc (' ');
 470             }
 471         }
 472       tui_putc ('\n');
 473     }
 474 }
 475
 476 /* Setup the IO for curses or non-curses mode.
 477    - In non-curses mode, readline and gdb use the standard input and
 478    standard output/error directly.
 479    - In curses mode, the standard output/error is controlled by TUI
 480    with the tui_stdout and tui_stderr.  The output is redirected in
 481    the curses command window.  Several readline callbacks are installed
 482    so that readline asks for its input to the curses command window
 483    with wgetch().  */
 484 void
 485 tui_setup_io (int mode)
 486 {
 487   extern int readline_echoing_p;
 488
 489   if (mode)
 490     {
 491       /* Redirect readline to TUI.  */
 492       tui_old_rl_redisplay_function = rl_redisplay_function;
 493       tui_old_rl_deprep_terminal = rl_deprep_term_function;
 494       tui_old_rl_prep_terminal = rl_prep_term_function;
 495       tui_old_rl_getc_function = rl_getc_function;
 496       tui_old_rl_outstream = rl_outstream;
 497       tui_old_readline_echoing_p = readline_echoing_p;
 498       rl_redisplay_function = tui_redisplay_readline;
 499       rl_deprep_term_function = tui_deprep_terminal;
 500       rl_prep_term_function = tui_prep_terminal;
 501       rl_getc_function = tui_getc;
 502       readline_echoing_p = 0;
 503       rl_outstream = tui_rl_outstream;
 504       rl_prompt = 0;
 505       rl_completion_display_matches_hook = tui_rl_display_match_list;
 506       rl_already_prompted = 0;
 507
 508       /* Keep track of previous gdb output.  */
 509       tui_old_stdout = gdb_stdout;
 510       tui_old_stderr = gdb_stderr;
 511       tui_old_uiout = uiout;
 512
 513       /* Reconfigure gdb output.  */
 514       gdb_stdout = tui_stdout;
 515       gdb_stderr = tui_stderr;
 516       gdb_stdlog = gdb_stdout;  /* for moment */
 517       gdb_stdtarg = gdb_stderr; /* for moment */
 518       uiout = tui_out;
 519
 520       /* Save tty for SIGCONT.  */
 521       savetty ();
 522     }
 523   else
 524     {
 525       /* Restore gdb output.  */
 526       gdb_stdout = tui_old_stdout;
 527       gdb_stderr = tui_old_stderr;
 528       gdb_stdlog = gdb_stdout;  /* for moment */
 529       gdb_stdtarg = gdb_stderr; /* for moment */
 530       uiout = tui_old_uiout;
 531
 532       /* Restore readline.  */
 533       rl_redisplay_function = tui_old_rl_redisplay_function;
 534       rl_deprep_term_function = tui_old_rl_deprep_terminal;
 535       rl_prep_term_function = tui_old_rl_prep_terminal;
 536       rl_getc_function = tui_old_rl_getc_function;
 537       rl_outstream = tui_old_rl_outstream;
 538       rl_completion_display_matches_hook = 0;
 539       readline_echoing_p = tui_old_readline_echoing_p;
 540       rl_already_prompted = 0;
 541
 542       /* Save tty for SIGCONT.  */
 543       savetty ();
 544     }
 545 }
 546
 547 #ifdef SIGCONT
 548 /* Catch SIGCONT to restore the terminal and refresh the screen.  */
 549 static void
 550 tui_cont_sig (int sig)
 551 {
 552   if (tui_active)
 553     {
 554       /* Restore the terminal setting because another process (shell)
 555          might have changed it.  */
 556       resetty ();
 557
 558       /* Force a refresh of the screen.  */
 559       tuiRefreshAll ();
 560
 561       /* Update cursor position on the screen.  */
 562       wmove (cmdWin->generic.handle,
 563              cmdWin->detail.commandInfo.start_line,
 564              cmdWin->detail.commandInfo.curch);
 565       wrefresh (cmdWin->generic.handle);
 566     }
 567   signal (sig, tui_cont_sig);
 568 }
 569 #endif
 570
 571 /* Initialize the IO for gdb in curses mode.  */
 572 void
 573 tui_initialize_io ()
 574 {
 575 #ifdef SIGCONT
 576   signal (SIGCONT, tui_cont_sig);
 577 #endif
 578
 579   /* Create tui output streams.  */
 580   tui_stdout = tui_fileopen (stdout);
 581   tui_stderr = tui_fileopen (stderr);
 582   tui_out = tui_out_new (tui_stdout);
 583
 584   /* Create the default UI.  It is not created because we installed
 585      a init_ui_hook.  */
 586   tui_old_uiout = uiout = cli_out_new (gdb_stdout);
 587
 588 #ifdef TUI_USE_PIPE_FOR_READLINE
 589   /* Temporary solution for readline writing to stdout:
 590      redirect readline output in a pipe, read that pipe and
 591      output the content in the curses command window.  */
 592   if (pipe (tui_readline_pipe) != 0)
 593     {
 594       fprintf_unfiltered (gdb_stderr, "Cannot create pipe for readline");
 595       exit (1);
 596     }
 597   tui_rl_outstream = fdopen (tui_readline_pipe[1], "w");
 598   if (tui_rl_outstream == 0)
 599     {
 600       fprintf_unfiltered (gdb_stderr, "Cannot redirect readline output");
 601       exit (1);
 602     }
 603   setvbuf (tui_rl_outstream, (char*) NULL, _IOLBF, 0);
 604
 605 #ifdef O_NONBLOCK
 606   (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NONBLOCK);
 607 #else
 608 #ifdef O_NDELAY
 609   (void) fcntl (tui_readline_pipe[0], F_SETFL, O_NDELAY);
 610 #endif
 611 #endif
 612   add_file_handler (tui_readline_pipe[0], tui_readline_output, 0);
 613 #else
 614   tui_rl_outstream = stdout;
 615 #endif
 616 }
 617
 618 /* Get a character from the command window.  This is called from the readline
 619    package.  */
 620 int
 621 tui_getc (FILE *fp)
 622 {
 623   int ch;
 624   WINDOW *w;
 625
 626   w = cmdWin->generic.handle;
 627
 628 #ifdef TUI_USE_PIPE_FOR_READLINE
 629   /* Flush readline output.  */
 630   tui_readline_output (GDB_READABLE, 0);
 631 #endif
 632
 633   ch = wgetch (w);
 634   ch = _tuiHandleResizeDuringIO (ch);
 635
 636   /* The \n must be echoed because it will not be printed by readline.  */
 637   if (ch == '\n')
 638     {
 639       /* When hitting return with an empty input, gdb executes the last
 640          command.  If we emit a newline, this fills up the command window
 641          with empty lines with gdb prompt at beginning.  Instead of that,
 642          stay on the same line but provide a visual effect to show the
 643          user we recognized the command.  */
 644       if (rl_end == 0)
 645         {
 646           wmove (w, cmdWin->detail.commandInfo.curLine, 0);
 647
 648           /* Clear the line.  This will blink the gdb prompt since
 649              it will be redrawn at the same line.  */
 650           wclrtoeol (w);
 651           wrefresh (w);
 652           napms (20);
 653         }
 654       else
 655         {
 656           wmove (w, cmdWin->detail.commandInfo.curLine,
 657                  cmdWin->detail.commandInfo.curch);
 658           waddch (w, ch);
 659         }
 660     }
 661
 662   if (m_isCommandChar (ch))
 663     {                           /* Handle prev/next/up/down here */
 664       ch = tuiDispatchCtrlChar (ch);
 665     }
 666
 667   if (ch == '\n' || ch == '\r' || ch == '\f')
 668     cmdWin->detail.commandInfo.curch = 0;
 669 #if 0
 670   else
 671     tuiIncrCommandCharCountBy (1);
 672 #endif
 673   if (ch == KEY_BACKSPACE)
 674     return '\b';
 675
 676   return ch;
 677 }
 678
 679
 680 /* Cleanup when a resize has occured.
 681    Returns the character that must be processed.  */
 682 static unsigned int
 683 _tuiHandleResizeDuringIO (unsigned int originalCh)
 684 {
 685   if (tuiWinResized ())
 686     {
 687       tuiRefreshAll ();
 688       dont_repeat ();
 689       tuiSetWinResizedTo (FALSE);
 690       return '\n';
 691     }
 692   else
 693     return originalCh;
 694 }