gdb/tui/tui-regs.c

   1 /* TUI display registers in window.
   2
   3    Copyright (C) 1998-2020 Free Software Foundation, Inc.
   4
   5    Contributed by Hewlett-Packard Company.
   6
   7    This file is part of GDB.
   8
   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.
  13
  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.
  18
  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/>.  */
  21
  22 #include "defs.h"
  23 #include "arch-utils.h"
  24 #include "tui/tui.h"
  25 #include "tui/tui-data.h"
  26 #include "symtab.h"
  27 #include "gdbtypes.h"
  28 #include "gdbcmd.h"
  29 #include "frame.h"
  30 #include "regcache.h"
  31 #include "inferior.h"
  32 #include "target.h"
  33 #include "tui/tui-layout.h"
  34 #include "tui/tui-win.h"
  35 #include "tui/tui-wingeneral.h"
  36 #include "tui/tui-file.h"
  37 #include "tui/tui-regs.h"
  38 #include "tui/tui-io.h"
  39 #include "reggroups.h"
  40 #include "valprint.h"
  41 #include "completer.h"
  42
  43 #include "gdb_curses.h"
  44
  45 /* A subclass of string_file that expands tab characters.  */
  46 class tab_expansion_file : public string_file
  47 {
  48 public:
  49
  50   tab_expansion_file () = default;
  51
  52   void write (const char *buf, long length_buf) override;
  53
  54 private:
  55
  56   int m_column = 0;
  57 };
  58
  59 void
  60 tab_expansion_file::write (const char *buf, long length_buf)
  61 {
  62   for (long i = 0; i < length_buf; ++i)
  63     {
  64       if (buf[i] == '\t')
  65         {
  66           do
  67             {
  68               string_file::write (" ", 1);
  69               ++m_column;
  70             }
  71           while ((m_column % 8) != 0);
  72         }
  73       else
  74         {
  75           string_file::write (&buf[i], 1);
  76           if (buf[i] == '\n')
  77             m_column = 0;
  78           else
  79             ++m_column;
  80         }
  81     }
  82 }
  83
  84 /* Get the register from the frame and return a printable
  85    representation of it.  */
  86
  87 static std::string
  88 tui_register_format (struct frame_info *frame, int regnum)
  89 {
  90   struct gdbarch *gdbarch = get_frame_arch (frame);
  91
  92   /* Expand tabs into spaces, since ncurses on MS-Windows doesn't.  */
  93   tab_expansion_file stream;
  94
  95   scoped_restore save_pagination
  96     = make_scoped_restore (&pagination_enabled, 0);
  97   scoped_restore save_stdout
  98     = make_scoped_restore (&gdb_stdout, &stream);
  99
 100   gdbarch_print_registers_info (gdbarch, &stream, frame, regnum, 1);
 101
 102   /* Remove the possible \n.  */
 103   std::string &str = stream.string ();
 104   if (!str.empty () && str.back () == '\n')
 105     str.resize (str.size () - 1);
 106
 107   return str;
 108 }
 109
 110 /* Get the register value from the given frame and format it for the
 111    display.  When changep is set, check if the new register value has
 112    changed with respect to the previous call.  */
 113 static void
 114 tui_get_register (struct frame_info *frame,
 115                   struct tui_data_item_window *data,
 116                   int regnum, bool *changedp)
 117 {
 118   if (changedp)
 119     *changedp = false;
 120   if (target_has_registers)
 121     {
 122       std::string new_content = tui_register_format (frame, regnum);
 123
 124       if (changedp != NULL && data->content != new_content)
 125         *changedp = true;
 126
 127       data->content = std::move (new_content);
 128     }
 129 }
 130
 131 /* See tui-regs.h.  */
 132
 133 int
 134 tui_data_window::last_regs_line_no () const
 135 {
 136   int num_lines = m_regs_content.size () / m_regs_column_count;
 137   if (m_regs_content.size () % m_regs_column_count)
 138     num_lines++;
 139   return num_lines;
 140 }
 141
 142 /* See tui-regs.h.  */
 143
 144 int
 145 tui_data_window::line_from_reg_element_no (int element_no) const
 146 {
 147   if (element_no < m_regs_content.size ())
 148     {
 149       int i, line = (-1);
 150
 151       i = 1;
 152       while (line == (-1))
 153         {
 154           if (element_no < m_regs_column_count * i)
 155             line = i - 1;
 156           else
 157             i++;
 158         }
 159
 160       return line;
 161     }
 162   else
 163     return (-1);
 164 }
 165
 166 /* See tui-regs.h.  */
 167
 168 int
 169 tui_data_window::first_reg_element_no_inline (int line_no) const
 170 {
 171   if (line_no * m_regs_column_count <= m_regs_content.size ())
 172     return ((line_no + 1) * m_regs_column_count) - m_regs_column_count;
 173   else
 174     return (-1);
 175 }
 176
 177 /* Show the registers of the given group in the data window
 178    and refresh the window.  */
 179 void
 180 tui_data_window::show_registers (struct reggroup *group)
 181 {
 182   if (group == 0)
 183     group = general_reggroup;
 184
 185   if (target_has_registers && target_has_stack && target_has_memory)
 186     {
 187       show_register_group (group, get_selected_frame (NULL),
 188                            group == m_current_group);
 189
 190       /* Clear all notation of changed values.  */
 191       for (auto &&data_item_win : m_regs_content)
 192         data_item_win.highlight = false;
 193       m_current_group = group;
 194     }
 195   else
 196     {
 197       m_current_group = 0;
 198       m_regs_content.clear ();
 199     }
 200
 201   rerender ();
 202 }
 203
 204
 205 /* Set the data window to display the registers of the register group
 206    using the given frame.  Values are refreshed only when
 207    refresh_values_only is true.  */
 208
 209 void
 210 tui_data_window::show_register_group (struct reggroup *group,
 211                                       struct frame_info *frame,
 212                                       bool refresh_values_only)
 213 {
 214   struct gdbarch *gdbarch = get_frame_arch (frame);
 215   int nr_regs;
 216   int regnum, pos;
 217
 218   /* Make a new title showing which group we display.  */
 219   title = string_printf ("Register group: %s", reggroup_name (group));
 220
 221   /* See how many registers must be displayed.  */
 222   nr_regs = 0;
 223   for (regnum = 0; regnum < gdbarch_num_cooked_regs (gdbarch); regnum++)
 224     {
 225       const char *name;
 226
 227       /* Must be in the group.  */
 228       if (!gdbarch_register_reggroup_p (gdbarch, regnum, group))
 229         continue;
 230
 231       /* If the register name is empty, it is undefined for this
 232          processor, so don't display anything.  */
 233       name = gdbarch_register_name (gdbarch, regnum);
 234       if (name == 0 || *name == '\0')
 235         continue;
 236
 237       nr_regs++;
 238     }
 239
 240   m_regs_content.resize (nr_regs);
 241
 242   /* Now set the register names and values.  */
 243   pos = 0;
 244   for (regnum = 0; regnum < gdbarch_num_cooked_regs (gdbarch); regnum++)
 245     {
 246       struct tui_data_item_window *data_item_win;
 247       const char *name;
 248
 249       /* Must be in the group.  */
 250       if (!gdbarch_register_reggroup_p (gdbarch, regnum, group))
 251         continue;
 252
 253       /* If the register name is empty, it is undefined for this
 254          processor, so don't display anything.  */
 255       name = gdbarch_register_name (gdbarch, regnum);
 256       if (name == 0 || *name == '\0')
 257         continue;
 258
 259       data_item_win = &m_regs_content[pos];
 260       if (!refresh_values_only)
 261         {
 262           data_item_win->item_no = regnum;
 263           data_item_win->highlight = false;
 264         }
 265       tui_get_register (frame, data_item_win, regnum, 0);
 266       pos++;
 267     }
 268 }
 269
 270 /* See tui-regs.h.  */
 271
 272 void
 273 tui_data_window::display_registers_from (int start_element_no)
 274 {
 275   int j, item_win_width, cur_y;
 276
 277   int max_len = 0;
 278   for (auto &&data_item_win : m_regs_content)
 279     {
 280       int len = data_item_win.content.size ();
 281
 282       if (len > max_len)
 283         max_len = len;
 284     }
 285   item_win_width = max_len + 1;
 286   int i = start_element_no;
 287
 288   m_regs_column_count = (width - 2) / item_win_width;
 289   if (m_regs_column_count == 0)
 290     m_regs_column_count = 1;
 291   item_win_width = (width - 2) / m_regs_column_count;
 292
 293   /* Now create each data "sub" window, and write the display into
 294      it.  */
 295   cur_y = 1;
 296   while (i < m_regs_content.size () && cur_y <= height - 2)
 297     {
 298       for (j = 0;
 299            j < m_regs_column_count && i < m_regs_content.size ();
 300            j++)
 301         {
 302           /* Create the window if necessary.  */
 303           m_regs_content[i].resize (1, item_win_width,
 304                                     x + (item_win_width * j) + 1, y + cur_y);
 305           i++;          /* Next register.  */
 306         }
 307       cur_y++;          /* Next row.  */
 308     }
 309 }
 310
 311 /* See tui-regs.h.  */
 312
 313 void
 314 tui_data_window::display_reg_element_at_line (int start_element_no,
 315                                               int start_line_no)
 316 {
 317   int element_no = start_element_no;
 318
 319   if (start_element_no != 0 && start_line_no != 0)
 320     {
 321       int last_line_no, first_line_on_last_page;
 322
 323       last_line_no = last_regs_line_no ();
 324       first_line_on_last_page = last_line_no - (height - 2);
 325       if (first_line_on_last_page < 0)
 326         first_line_on_last_page = 0;
 327
 328       /* If the element_no causes us to scroll past the end of the
 329          registers, adjust what element to really start the
 330          display at.  */
 331       if (start_line_no > first_line_on_last_page)
 332         element_no = first_reg_element_no_inline (first_line_on_last_page);
 333     }
 334   display_registers_from (element_no);
 335 }
 336
 337 /* See tui-regs.h.  */
 338
 339 int
 340 tui_data_window::display_registers_from_line (int line_no)
 341 {
 342   int element_no;
 343
 344   if (line_no < 0)
 345     line_no = 0;
 346   else
 347     {
 348       /* Make sure that we don't display off the end of the
 349          registers.  */
 350       if (line_no >= last_regs_line_no ())
 351         {
 352           line_no = line_from_reg_element_no (m_regs_content.size () - 1);
 353           if (line_no < 0)
 354             line_no = 0;
 355         }
 356     }
 357
 358   element_no = first_reg_element_no_inline (line_no);
 359   if (element_no < m_regs_content.size ())
 360     display_reg_element_at_line (element_no, line_no);
 361   else
 362     line_no = (-1);
 363
 364   return line_no;
 365 }
 366
 367
 368 /* Answer the index first element displayed.  If none are displayed,
 369    then return (-1).  */
 370 int
 371 tui_data_window::first_data_item_displayed ()
 372 {
 373   for (int i = 0; i < m_regs_content.size (); i++)
 374     {
 375       struct tui_gen_win_info *data_item_win;
 376
 377       data_item_win = &m_regs_content[i];
 378       if (data_item_win->is_visible ())
 379         return i;
 380     }
 381
 382   return -1;
 383 }
 384
 385 /* See tui-regs.h.  */
 386
 387 void
 388 tui_data_window::delete_data_content_windows ()
 389 {
 390   for (auto &&win : m_regs_content)
 391     win.handle.reset (nullptr);
 392 }
 393
 394
 395 void
 396 tui_data_window::erase_data_content (const char *prompt)
 397 {
 398   werase (handle.get ());
 399   check_and_display_highlight_if_needed ();
 400   if (prompt != NULL)
 401     {
 402       int half_width = (width - 2) / 2;
 403       int x_pos;
 404
 405       if (strlen (prompt) >= half_width)
 406         x_pos = 1;
 407       else
 408         x_pos = half_width - strlen (prompt);
 409       mvwaddstr (handle.get (), (height / 2), x_pos, (char *) prompt);
 410     }
 411   tui_wrefresh (handle.get ());
 412 }
 413
 414 /* See tui-regs.h.  */
 415
 416 void
 417 tui_data_window::rerender ()
 418 {
 419   if (m_regs_content.empty ())
 420     erase_data_content (_("[ Register Values Unavailable ]"));
 421   else
 422     {
 423       erase_data_content (NULL);
 424       delete_data_content_windows ();
 425       display_registers_from (0);
 426     }
 427 }
 428
 429
 430 /* Scroll the data window vertically forward or backward.  */
 431 void
 432 tui_data_window::do_scroll_vertical (int num_to_scroll)
 433 {
 434   int first_element_no;
 435   int first_line = (-1);
 436
 437   first_element_no = first_data_item_displayed ();
 438   if (first_element_no < m_regs_content.size ())
 439     first_line = line_from_reg_element_no (first_element_no);
 440   else
 441     { /* Calculate the first line from the element number which is in
 442         the general data content.  */
 443     }
 444
 445   if (first_line >= 0)
 446     {
 447       first_line += num_to_scroll;
 448       erase_data_content (NULL);
 449       delete_data_content_windows ();
 450       display_registers_from_line (first_line);
 451     }
 452 }
 453
 454 /* See tui-regs.h.  */
 455
 456 void
 457 tui_data_window::refresh_window ()
 458 {
 459   tui_gen_win_info::refresh_window ();
 460   for (auto &&win : m_regs_content)
 461     win.refresh_window ();
 462 }
 463
 464 void
 465 tui_data_window::no_refresh ()
 466 {
 467   tui_gen_win_info::no_refresh ();
 468   for (auto &&win : m_regs_content)
 469     win.no_refresh ();
 470 }
 471
 472 /* This function check all displayed registers for changes in values,
 473    given a particular frame.  If the values have changed, they are
 474    updated with the new value and highlighted.  */
 475 void
 476 tui_data_window::check_register_values (struct frame_info *frame)
 477 {
 478   if (m_regs_content.empty ())
 479     show_registers (m_current_group);
 480   else
 481     {
 482       for (auto &&data_item_win : m_regs_content)
 483         {
 484           int was_hilighted;
 485
 486           was_hilighted = data_item_win.highlight;
 487
 488           tui_get_register (frame, &data_item_win,
 489                             data_item_win.item_no,
 490                             &data_item_win.highlight);
 491
 492           if (data_item_win.highlight || was_hilighted)
 493             data_item_win.rerender ();
 494         }
 495     }
 496 }
 497
 498 /* Display a register in a window.  If hilite is TRUE, then the value
 499    will be displayed in reverse video.  */
 500 void
 501 tui_data_item_window::rerender ()
 502 {
 503   int i;
 504
 505   scrollok (handle.get (), FALSE);
 506   if (highlight)
 507     /* We ignore the return value, casting it to void in order to avoid
 508        a compiler warning.  The warning itself was introduced by a patch
 509        to ncurses 5.7 dated 2009-08-29, changing this macro to expand
 510        to code that causes the compiler to generate an unused-value
 511        warning.  */
 512     (void) wstandout (handle.get ());
 513
 514   wmove (handle.get (), 0, 0);
 515   for (i = 1; i < width; i++)
 516     waddch (handle.get (), ' ');
 517   wmove (handle.get (), 0, 0);
 518   waddstr (handle.get (), content.c_str ());
 519
 520   if (highlight)
 521     /* We ignore the return value, casting it to void in order to avoid
 522        a compiler warning.  The warning itself was introduced by a patch
 523        to ncurses 5.7 dated 2009-08-29, changing this macro to expand
 524        to code that causes the compiler to generate an unused-value
 525        warning.  */
 526     (void) wstandend (handle.get ());
 527   refresh_window ();
 528 }
 529
 530 void
 531 tui_data_item_window::refresh_window ()
 532 {
 533   if (handle != nullptr)
 534     {
 535       /* This seems to be needed because the data items are nested
 536          windows, which according to the ncurses man pages aren't well
 537          supported.  */
 538       touchwin (handle.get ());
 539       tui_wrefresh (handle.get ());
 540     }
 541 }
 542
 543 /* Helper for "tui reg next", wraps a call to REGGROUP_NEXT, but adds wrap
 544    around behaviour.  Returns the next register group, or NULL if the
 545    register window is not currently being displayed.  */
 546
 547 static struct reggroup *
 548 tui_reg_next (struct reggroup *current_group, struct gdbarch *gdbarch)
 549 {
 550   struct reggroup *group = NULL;
 551
 552   if (current_group != NULL)
 553     {
 554       group = reggroup_next (gdbarch, current_group);
 555       if (group == NULL)
 556         group = reggroup_next (gdbarch, NULL);
 557     }
 558   return group;
 559 }
 560
 561 /* Helper for "tui reg prev", wraps a call to REGGROUP_PREV, but adds wrap
 562    around behaviour.  Returns the previous register group, or NULL if the
 563    register window is not currently being displayed.  */
 564
 565 static struct reggroup *
 566 tui_reg_prev (struct reggroup *current_group, struct gdbarch *gdbarch)
 567 {
 568   struct reggroup *group = NULL;
 569
 570   if (current_group != NULL)
 571     {
 572       group = reggroup_prev (gdbarch, current_group);
 573       if (group == NULL)
 574         group = reggroup_prev (gdbarch, NULL);
 575     }
 576   return group;
 577 }
 578
 579 /* Implement the 'tui reg' command.  Changes the register group displayed
 580    in the tui register window.  Displays the tui register window if it is
 581    not already on display.  */
 582
 583 static void
 584 tui_reg_command (const char *args, int from_tty)
 585 {
 586   struct gdbarch *gdbarch = get_current_arch ();
 587
 588   if (args != NULL)
 589     {
 590       struct reggroup *group, *match = NULL;
 591       size_t len = strlen (args);
 592
 593       /* Make sure the curses mode is enabled.  */
 594       tui_enable ();
 595
 596       tui_suppress_output suppress;
 597
 598       /* Make sure the register window is visible.  If not, select an
 599          appropriate layout.  We need to do this before trying to run the
 600          'next' or 'prev' commands.  */
 601       if (TUI_DATA_WIN == NULL || !TUI_DATA_WIN->is_visible ())
 602         tui_regs_layout ();
 603
 604       struct reggroup *current_group = TUI_DATA_WIN->get_current_group ();
 605       if (strncmp (args, "next", len) == 0)
 606         match = tui_reg_next (current_group, gdbarch);
 607       else if (strncmp (args, "prev", len) == 0)
 608         match = tui_reg_prev (current_group, gdbarch);
 609
 610       /* This loop matches on the initial part of a register group
 611          name.  If this initial part in ARGS matches only one register
 612          group then the switch is made.  */
 613       for (group = reggroup_next (gdbarch, NULL);
 614            group != NULL;
 615            group = reggroup_next (gdbarch, group))
 616         {
 617           if (strncmp (reggroup_name (group), args, len) == 0)
 618             {
 619               if (match != NULL)
 620                 error (_("ambiguous register group name '%s'"), args);
 621               match = group;
 622             }
 623         }
 624
 625       if (match == NULL)
 626         error (_("unknown register group '%s'"), args);
 627
 628       TUI_DATA_WIN->show_registers (match);
 629     }
 630   else
 631     {
 632       struct reggroup *group;
 633       int first;
 634
 635       printf_unfiltered (_("\"tui reg\" must be followed by the name of "
 636                            "either a register group,\nor one of 'next' "
 637                            "or 'prev'.  Known register groups are:\n"));
 638
 639       for (first = 1, group = reggroup_next (gdbarch, NULL);
 640            group != NULL;
 641            first = 0, group = reggroup_next (gdbarch, group))
 642         {
 643           if (!first)
 644             printf_unfiltered (", ");
 645           printf_unfiltered ("%s", reggroup_name (group));
 646         }
 647
 648       printf_unfiltered ("\n");
 649     }
 650 }
 651
 652 /* Complete names of register groups, and add the special "prev" and "next"
 653    names.  */
 654
 655 static void
 656 tui_reggroup_completer (struct cmd_list_element *ignore,
 657                         completion_tracker &tracker,
 658                         const char *text, const char *word)
 659 {
 660   static const char * const extra[] = { "next", "prev", NULL };
 661
 662   reggroup_completer (ignore, tracker, text, word);
 663
 664   complete_on_enum (tracker, extra, text, word);
 665 }
 666
 667 void _initialize_tui_regs ();
 668 void
 669 _initialize_tui_regs ()
 670 {
 671   struct cmd_list_element **tuicmd, *cmd;
 672
 673   tuicmd = tui_get_cmd_list ();
 674
 675   cmd = add_cmd ("reg", class_tui, tui_reg_command, _("\
 676 TUI command to control the register window.\n\
 677 Usage: tui reg NAME\n\
 678 NAME is the name of the register group to display"), tuicmd);
 679   set_cmd_completer (cmd, tui_reggroup_completer);
 680 }