gdb/tui/tui-regs.c

   1 /* TUI display registers in window.
   2
   3    Copyright (C) 1998-2023 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 (frame_info_ptr 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   gdbarch_print_registers_info (gdbarch, &stream, frame, regnum, 1);
  95
  96   /* Remove the possible \n.  */
  97   std::string str = stream.release ();
  98   if (!str.empty () && str.back () == '\n')
  99     str.resize (str.size () - 1);
 100
 101   return str;
 102 }
 103
 104 /* Get the register value from the given frame and format it for the
 105    display.  When changedp is set, check if the new register value has
 106    changed with respect to the previous call.  */
 107 static void
 108 tui_get_register (frame_info_ptr frame,
 109                   struct tui_data_item_window *data,
 110                   int regnum, bool *changedp)
 111 {
 112   if (changedp)
 113     *changedp = false;
 114   if (target_has_registers ())
 115     {
 116       std::string new_content = tui_register_format (frame, regnum);
 117
 118       if (changedp != NULL && data->content != new_content)
 119         *changedp = true;
 120
 121       data->content = std::move (new_content);
 122     }
 123 }
 124
 125 /* See tui-regs.h.  */
 126
 127 int
 128 tui_data_window::last_regs_line_no () const
 129 {
 130   int num_lines = m_regs_content.size () / m_regs_column_count;
 131   if (m_regs_content.size () % m_regs_column_count)
 132     num_lines++;
 133   return num_lines;
 134 }
 135
 136 /* See tui-regs.h.  */
 137
 138 int
 139 tui_data_window::line_from_reg_element_no (int element_no) const
 140 {
 141   if (element_no < m_regs_content.size ())
 142     {
 143       int i, line = (-1);
 144
 145       i = 1;
 146       while (line == (-1))
 147         {
 148           if (element_no < m_regs_column_count * i)
 149             line = i - 1;
 150           else
 151             i++;
 152         }
 153
 154       return line;
 155     }
 156   else
 157     return (-1);
 158 }
 159
 160 /* See tui-regs.h.  */
 161
 162 int
 163 tui_data_window::first_reg_element_no_inline (int line_no) const
 164 {
 165   if (line_no * m_regs_column_count <= m_regs_content.size ())
 166     return ((line_no + 1) * m_regs_column_count) - m_regs_column_count;
 167   else
 168     return (-1);
 169 }
 170
 171 /* Show the registers of the given group in the data window
 172    and refresh the window.  */
 173 void
 174 tui_data_window::show_registers (const reggroup *group)
 175 {
 176   if (group == 0)
 177     group = general_reggroup;
 178
 179   if (target_has_registers () && target_has_stack () && target_has_memory ())
 180     {
 181       show_register_group (group, get_selected_frame (NULL),
 182                            group == m_current_group);
 183
 184       /* Clear all notation of changed values.  */
 185       for (auto &&data_item_win : m_regs_content)
 186         data_item_win.highlight = false;
 187       m_current_group = group;
 188     }
 189   else
 190     {
 191       m_current_group = 0;
 192       m_regs_content.clear ();
 193     }
 194
 195   rerender ();
 196 }
 197
 198
 199 /* Set the data window to display the registers of the register group
 200    using the given frame.  Values are refreshed only when
 201    refresh_values_only is true.  */
 202
 203 void
 204 tui_data_window::show_register_group (const reggroup *group,
 205                                       frame_info_ptr frame,
 206                                       bool refresh_values_only)
 207 {
 208   struct gdbarch *gdbarch = get_frame_arch (frame);
 209   int nr_regs;
 210   int regnum, pos;
 211
 212   /* Make a new title showing which group we display.  */
 213   this->set_title (string_printf ("Register group: %s", group->name ()));
 214
 215   /* See how many registers must be displayed.  */
 216   nr_regs = 0;
 217   for (regnum = 0; regnum < gdbarch_num_cooked_regs (gdbarch); regnum++)
 218     {
 219       const char *name;
 220
 221       /* Must be in the group.  */
 222       if (!gdbarch_register_reggroup_p (gdbarch, regnum, group))
 223         continue;
 224
 225       /* If the register name is empty, it is undefined for this
 226          processor, so don't display anything.  */
 227       name = gdbarch_register_name (gdbarch, regnum);
 228       if (*name == '\0')
 229         continue;
 230
 231       nr_regs++;
 232     }
 233
 234   m_regs_content.resize (nr_regs);
 235
 236   /* Now set the register names and values.  */
 237   pos = 0;
 238   for (regnum = 0; regnum < gdbarch_num_cooked_regs (gdbarch); regnum++)
 239     {
 240       struct tui_data_item_window *data_item_win;
 241       const char *name;
 242
 243       /* Must be in the group.  */
 244       if (!gdbarch_register_reggroup_p (gdbarch, regnum, group))
 245         continue;
 246
 247       /* If the register name is empty, it is undefined for this
 248          processor, so don't display anything.  */
 249       name = gdbarch_register_name (gdbarch, regnum);
 250       if (*name == '\0')
 251         continue;
 252
 253       data_item_win = &m_regs_content[pos];
 254       if (!refresh_values_only)
 255         {
 256           data_item_win->regno = regnum;
 257           data_item_win->highlight = false;
 258         }
 259       tui_get_register (frame, data_item_win, regnum, 0);
 260       pos++;
 261     }
 262 }
 263
 264 /* See tui-regs.h.  */
 265
 266 void
 267 tui_data_window::display_registers_from (int start_element_no)
 268 {
 269   int max_len = 0;
 270   for (auto &&data_item_win : m_regs_content)
 271     {
 272       int len = data_item_win.content.size ();
 273
 274       if (len > max_len)
 275         max_len = len;
 276     }
 277   m_item_width = max_len + 1;
 278
 279   int i;
 280   /* Mark register windows above the visible area.  */
 281   for (i = 0; i < start_element_no; i++)
 282     m_regs_content[i].y = 0;
 283
 284   m_regs_column_count = (width - box_size ()) / m_item_width;
 285   if (m_regs_column_count == 0)
 286     m_regs_column_count = 1;
 287   m_item_width = (width - box_size ()) / m_regs_column_count;
 288
 289   /* Now create each data "sub" window, and write the display into
 290      it.  */
 291   int cur_y = 1;
 292   while (i < m_regs_content.size () && cur_y <= height - box_size ())
 293     {
 294       for (int j = 0;
 295            j < m_regs_column_count && i < m_regs_content.size ();
 296            j++)
 297         {
 298           /* Create the window if necessary.  */
 299           m_regs_content[i].x = (m_item_width * j) + 1;
 300           m_regs_content[i].y = cur_y;
 301           m_regs_content[i].visible = true;
 302           m_regs_content[i].rerender (handle.get (), m_item_width);
 303           i++;          /* Next register.  */
 304         }
 305       cur_y++;          /* Next row.  */
 306     }
 307
 308   /* Mark register windows below the visible area.  */
 309   for (; i < m_regs_content.size (); i++)
 310     m_regs_content[i].y = 0;
 311
 312   refresh_window ();
 313 }
 314
 315 /* See tui-regs.h.  */
 316
 317 void
 318 tui_data_window::display_reg_element_at_line (int start_element_no,
 319                                               int start_line_no)
 320 {
 321   int element_no = start_element_no;
 322
 323   if (start_element_no != 0 && start_line_no != 0)
 324     {
 325       int last_line_no, first_line_on_last_page;
 326
 327       last_line_no = last_regs_line_no ();
 328       first_line_on_last_page = last_line_no - (height - box_size ());
 329       if (first_line_on_last_page < 0)
 330         first_line_on_last_page = 0;
 331
 332       /* If the element_no causes us to scroll past the end of the
 333          registers, adjust what element to really start the
 334          display at.  */
 335       if (start_line_no > first_line_on_last_page)
 336         element_no = first_reg_element_no_inline (first_line_on_last_page);
 337     }
 338   display_registers_from (element_no);
 339 }
 340
 341 /* See tui-regs.h.  */
 342
 343 int
 344 tui_data_window::display_registers_from_line (int line_no)
 345 {
 346   int element_no;
 347
 348   if (line_no < 0)
 349     line_no = 0;
 350   else
 351     {
 352       /* Make sure that we don't display off the end of the
 353          registers.  */
 354       if (line_no >= last_regs_line_no ())
 355         {
 356           line_no = line_from_reg_element_no (m_regs_content.size () - 1);
 357           if (line_no < 0)
 358             line_no = 0;
 359         }
 360     }
 361
 362   element_no = first_reg_element_no_inline (line_no);
 363   if (element_no < m_regs_content.size ())
 364     display_reg_element_at_line (element_no, line_no);
 365   else
 366     line_no = (-1);
 367
 368   return line_no;
 369 }
 370
 371
 372 /* Answer the index first element displayed.  If none are displayed,
 373    then return (-1).  */
 374 int
 375 tui_data_window::first_data_item_displayed ()
 376 {
 377   for (int i = 0; i < m_regs_content.size (); i++)
 378     {
 379       if (m_regs_content[i].visible)
 380         return i;
 381     }
 382
 383   return -1;
 384 }
 385
 386 /* See tui-regs.h.  */
 387
 388 void
 389 tui_data_window::delete_data_content_windows ()
 390 {
 391   for (auto &win : m_regs_content)
 392     win.visible = false;
 393 }
 394
 395
 396 void
 397 tui_data_window::erase_data_content (const char *prompt)
 398 {
 399   werase (handle.get ());
 400   check_and_display_highlight_if_needed ();
 401   if (prompt != NULL)
 402     {
 403       int half_width = (width - box_size ()) / 2;
 404       int x_pos;
 405
 406       if (strlen (prompt) >= half_width)
 407         x_pos = 1;
 408       else
 409         x_pos = half_width - strlen (prompt);
 410       mvwaddstr (handle.get (), (height / 2), x_pos, (char *) prompt);
 411     }
 412   tui_wrefresh (handle.get ());
 413 }
 414
 415 /* See tui-regs.h.  */
 416
 417 void
 418 tui_data_window::rerender ()
 419 {
 420   if (m_regs_content.empty ())
 421     erase_data_content (_("[ Register Values Unavailable ]"));
 422   else
 423     {
 424       erase_data_content (NULL);
 425       delete_data_content_windows ();
 426       display_registers_from (0);
 427     }
 428 }
 429
 430
 431 /* Scroll the data window vertically forward or backward.  */
 432 void
 433 tui_data_window::do_scroll_vertical (int num_to_scroll)
 434 {
 435   int first_element_no;
 436   int first_line = (-1);
 437
 438   first_element_no = first_data_item_displayed ();
 439   if (first_element_no < m_regs_content.size ())
 440     first_line = line_from_reg_element_no (first_element_no);
 441   else
 442     { /* Calculate the first line from the element number which is in
 443         the general data content.  */
 444     }
 445
 446   if (first_line >= 0)
 447     {
 448       first_line += num_to_scroll;
 449       erase_data_content (NULL);
 450       delete_data_content_windows ();
 451       display_registers_from_line (first_line);
 452     }
 453 }
 454
 455 /* This function check all displayed registers for changes in values,
 456    given a particular frame.  If the values have changed, they are
 457    updated with the new value and highlighted.  */
 458 void
 459 tui_data_window::check_register_values (frame_info_ptr frame)
 460 {
 461   if (m_regs_content.empty ())
 462     show_registers (m_current_group);
 463   else
 464     {
 465       for (auto &&data_item_win : m_regs_content)
 466         {
 467           int was_hilighted;
 468
 469           was_hilighted = data_item_win.highlight;
 470
 471           tui_get_register (frame, &data_item_win,
 472                             data_item_win.regno,
 473                             &data_item_win.highlight);
 474
 475           /* Register windows whose y == 0 are outside the visible area.  */
 476           if ((data_item_win.highlight || was_hilighted)
 477               && data_item_win.y > 0)
 478             data_item_win.rerender (handle.get (), m_item_width);
 479         }
 480     }
 481
 482   tui_wrefresh (handle.get ());
 483 }
 484
 485 /* Display a register in a window.  If hilite is TRUE, then the value
 486    will be displayed in reverse video.  */
 487 void
 488 tui_data_item_window::rerender (WINDOW *handle, int field_width)
 489 {
 490   if (highlight)
 491     /* We ignore the return value, casting it to void in order to avoid
 492        a compiler warning.  The warning itself was introduced by a patch
 493        to ncurses 5.7 dated 2009-08-29, changing this macro to expand
 494        to code that causes the compiler to generate an unused-value
 495        warning.  */
 496     (void) wstandout (handle);
 497
 498   mvwaddnstr (handle, y, x, content.c_str (), field_width - 1);
 499   if (content.size () < field_width)
 500     waddstr (handle, n_spaces (field_width - content.size ()));
 501
 502   if (highlight)
 503     /* We ignore the return value, casting it to void in order to avoid
 504        a compiler warning.  The warning itself was introduced by a patch
 505        to ncurses 5.7 dated 2009-08-29, changing this macro to expand
 506        to code that causes the compiler to generate an unused-value
 507        warning.  */
 508     (void) wstandend (handle);
 509 }
 510
 511 /* Helper for "tui reg next", returns the next register group after
 512    CURRENT_GROUP in the register group list for GDBARCH, with wrap around
 513    behaviour.
 514
 515    If CURRENT_GROUP is nullptr (e.g. if the tui register window has only
 516    just been displayed and has no current group selected) or the currently
 517    selected register group can't be found (e.g. if the architecture has
 518    changed since the register window was last updated), then the first
 519    register group will be returned.  */
 520
 521 static const reggroup *
 522 tui_reg_next (const reggroup *current_group, struct gdbarch *gdbarch)
 523 {
 524   const std::vector<const reggroup *> &groups = gdbarch_reggroups (gdbarch);
 525   auto it = std::find (groups.begin (), groups.end (), current_group);
 526   if (it != groups.end ())
 527     it++;
 528   if (it == groups.end ())
 529     return groups.front ();
 530   return *it;
 531 }
 532
 533 /* Helper for "tui reg prev", returns the register group previous to
 534    CURRENT_GROUP in the register group list for GDBARCH, with wrap around
 535    behaviour.
 536
 537    If CURRENT_GROUP is nullptr (e.g. if the tui register window has only
 538    just been displayed and has no current group selected) or the currently
 539    selected register group can't be found (e.g. if the architecture has
 540    changed since the register window was last updated), then the last
 541    register group will be returned.  */
 542
 543 static const reggroup *
 544 tui_reg_prev (const reggroup *current_group, struct gdbarch *gdbarch)
 545 {
 546   const std::vector<const reggroup *> &groups = gdbarch_reggroups (gdbarch);
 547   auto it = std::find (groups.rbegin (), groups.rend (), current_group);
 548   if (it != groups.rend ())
 549     it++;
 550   if (it == groups.rend ())
 551     return groups.back ();
 552   return *it;
 553 }
 554
 555 /* Implement the 'tui reg' command.  Changes the register group displayed
 556    in the tui register window.  Displays the tui register window if it is
 557    not already on display.  */
 558
 559 static void
 560 tui_reg_command (const char *args, int from_tty)
 561 {
 562   struct gdbarch *gdbarch = get_current_arch ();
 563
 564   if (args != NULL)
 565     {
 566       size_t len = strlen (args);
 567
 568       /* Make sure the curses mode is enabled.  */
 569       tui_enable ();
 570
 571       tui_suppress_output suppress;
 572
 573       /* Make sure the register window is visible.  If not, select an
 574          appropriate layout.  We need to do this before trying to run the
 575          'next' or 'prev' commands.  */
 576       if (TUI_DATA_WIN == NULL || !TUI_DATA_WIN->is_visible ())
 577         tui_regs_layout ();
 578
 579       const reggroup *match = nullptr;
 580       const reggroup *current_group = TUI_DATA_WIN->get_current_group ();
 581       if (strncmp (args, "next", len) == 0)
 582         match = tui_reg_next (current_group, gdbarch);
 583       else if (strncmp (args, "prev", len) == 0)
 584         match = tui_reg_prev (current_group, gdbarch);
 585       else
 586         {
 587           /* This loop matches on the initial part of a register group
 588              name.  If this initial part in ARGS matches only one register
 589              group then the switch is made.  */
 590           for (const struct reggroup *group : gdbarch_reggroups (gdbarch))
 591             {
 592               if (strncmp (group->name (), args, len) == 0)
 593                 {
 594                   if (match != NULL)
 595                     error (_("ambiguous register group name '%s'"), args);
 596                   match = group;
 597                 }
 598             }
 599         }
 600
 601       if (match == NULL)
 602         error (_("unknown register group '%s'"), args);
 603
 604       TUI_DATA_WIN->show_registers (match);
 605     }
 606   else
 607     {
 608       gdb_printf (_("\"tui reg\" must be followed by the name of "
 609                     "either a register group,\nor one of 'next' "
 610                     "or 'prev'.  Known register groups are:\n"));
 611
 612       bool first = true;
 613       for (const struct reggroup *group : gdbarch_reggroups (gdbarch))
 614         {
 615           if (!first)
 616             gdb_printf (", ");
 617           first = false;
 618           gdb_printf ("%s", group->name ());
 619         }
 620
 621       gdb_printf ("\n");
 622     }
 623 }
 624
 625 /* Complete names of register groups, and add the special "prev" and "next"
 626    names.  */
 627
 628 static void
 629 tui_reggroup_completer (struct cmd_list_element *ignore,
 630                         completion_tracker &tracker,
 631                         const char *text, const char *word)
 632 {
 633   static const char * const extra[] = { "next", "prev", NULL };
 634
 635   reggroup_completer (ignore, tracker, text, word);
 636
 637   complete_on_enum (tracker, extra, text, word);
 638 }
 639
 640 void _initialize_tui_regs ();
 641 void
 642 _initialize_tui_regs ()
 643 {
 644   struct cmd_list_element **tuicmd, *cmd;
 645
 646   tuicmd = tui_get_cmd_list ();
 647
 648   cmd = add_cmd ("reg", class_tui, tui_reg_command, _("\
 649 TUI command to control the register window.\n\
 650 Usage: tui reg NAME\n\
 651 NAME is the name of the register group to display"), tuicmd);
 652   set_cmd_completer (cmd, tui_reggroup_completer);
 653 }