gdb/tui/tui-disasm.c

   1 /* Disassembly display.
   2
   3    Copyright (C) 1998-2016 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 "symtab.h"
  25 #include "breakpoint.h"
  26 #include "frame.h"
  27 #include "value.h"
  28 #include "source.h"
  29 #include "disasm.h"
  30 #include "tui/tui.h"
  31 #include "tui/tui-data.h"
  32 #include "tui/tui-win.h"
  33 #include "tui/tui-layout.h"
  34 #include "tui/tui-winsource.h"
  35 #include "tui/tui-stack.h"
  36 #include "tui/tui-file.h"
  37 #include "tui/tui-disasm.h"
  38 #include "progspace.h"
  39 #include "objfiles.h"
  40
  41 #include "gdb_curses.h"
  42
  43 struct tui_asm_line
  44 {
  45   CORE_ADDR addr;
  46   char *addr_string;
  47   char *insn;
  48 };
  49
  50 /* Function to set the disassembly window's content.
  51    Disassemble count lines starting at pc.
  52    Return address of the count'th instruction after pc.  */
  53 static CORE_ADDR
  54 tui_disassemble (struct gdbarch *gdbarch, struct tui_asm_line *asm_lines,
  55                  CORE_ADDR pc, int count)
  56 {
  57   struct ui_file *gdb_dis_out;
  58
  59   /* Now init the ui_file structure.  */
  60   gdb_dis_out = tui_sfileopen (256);
  61
  62   /* Now construct each line.  */
  63   for (; count > 0; count--, asm_lines++)
  64     {
  65       if (asm_lines->addr_string)
  66         xfree (asm_lines->addr_string);
  67       if (asm_lines->insn)
  68         xfree (asm_lines->insn);
  69
  70       print_address (gdbarch, pc, gdb_dis_out);
  71       asm_lines->addr = pc;
  72       asm_lines->addr_string = xstrdup (tui_file_get_strbuf (gdb_dis_out));
  73
  74       ui_file_rewind (gdb_dis_out);
  75
  76       pc = pc + gdb_print_insn (gdbarch, pc, gdb_dis_out, NULL);
  77
  78       asm_lines->insn = xstrdup (tui_file_get_strbuf (gdb_dis_out));
  79
  80       /* Reset the buffer to empty.  */
  81       ui_file_rewind (gdb_dis_out);
  82     }
  83   ui_file_delete (gdb_dis_out);
  84   return pc;
  85 }
  86
  87 /* Find the disassembly address that corresponds to FROM lines above
  88    or below the PC.  Variable sized instructions are taken into
  89    account by the algorithm.  */
  90 static CORE_ADDR
  91 tui_find_disassembly_address (struct gdbarch *gdbarch, CORE_ADDR pc, int from)
  92 {
  93   CORE_ADDR new_low;
  94   int max_lines;
  95   int i;
  96   struct tui_asm_line *asm_lines;
  97
  98   max_lines = (from > 0) ? from : - from;
  99   if (max_lines <= 1)
 100      return pc;
 101
 102   asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
 103   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 104
 105   new_low = pc;
 106   if (from > 0)
 107     {
 108       tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 109       new_low = asm_lines[max_lines - 1].addr;
 110     }
 111   else
 112     {
 113       CORE_ADDR last_addr;
 114       int pos;
 115       struct bound_minimal_symbol msymbol;
 116
 117       /* Find backward an address which is a symbol and for which
 118          disassembling from that address will fill completely the
 119          window.  */
 120       pos = max_lines - 1;
 121       do {
 122          new_low -= 1 * max_lines;
 123          msymbol = lookup_minimal_symbol_by_pc_section (new_low, 0);
 124
 125          if (msymbol.minsym)
 126             new_low = BMSYMBOL_VALUE_ADDRESS (msymbol);
 127          else
 128             new_low += 1 * max_lines;
 129
 130          tui_disassemble (gdbarch, asm_lines, new_low, max_lines);
 131          last_addr = asm_lines[pos].addr;
 132       } while (last_addr > pc && msymbol.minsym);
 133
 134       /* Scan forward disassembling one instruction at a time until
 135          the last visible instruction of the window matches the pc.
 136          We keep the disassembled instructions in the 'lines' window
 137          and shift it downward (increasing its addresses).  */
 138       if (last_addr < pc)
 139         do
 140           {
 141             CORE_ADDR next_addr;
 142
 143             pos++;
 144             if (pos >= max_lines)
 145               pos = 0;
 146
 147             next_addr = tui_disassemble (gdbarch, &asm_lines[pos],
 148                                          last_addr, 1);
 149
 150             /* If there are some problems while disassembling exit.  */
 151             if (next_addr <= last_addr)
 152               break;
 153             last_addr = next_addr;
 154           } while (last_addr <= pc);
 155       pos++;
 156       if (pos >= max_lines)
 157          pos = 0;
 158       new_low = asm_lines[pos].addr;
 159     }
 160   for (i = 0; i < max_lines; i++)
 161     {
 162       xfree (asm_lines[i].addr_string);
 163       xfree (asm_lines[i].insn);
 164     }
 165   return new_low;
 166 }
 167
 168 /* Function to set the disassembly window's content.  */
 169 enum tui_status
 170 tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
 171 {
 172   enum tui_status ret = TUI_FAILURE;
 173   int i;
 174   int offset = TUI_DISASM_WIN->detail.source_info.horizontal_offset;
 175   int max_lines, line_width;
 176   CORE_ADDR cur_pc;
 177   struct tui_gen_win_info *locator = tui_locator_win_info_ptr ();
 178   int tab_len = tui_default_tab_len ();
 179   struct tui_asm_line *asm_lines;
 180   int insn_pos;
 181   int addr_size, max_size;
 182   char *line;
 183
 184   if (pc == 0)
 185     return TUI_FAILURE;
 186
 187   ret = tui_alloc_source_buffer (TUI_DISASM_WIN);
 188   if (ret != TUI_SUCCESS)
 189     return ret;
 190
 191   TUI_DISASM_WIN->detail.source_info.gdbarch = gdbarch;
 192   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.loa = LOA_ADDRESS;
 193   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.u.addr = pc;
 194   cur_pc = locator->content[0]->which_element.locator.addr;
 195
 196   /* Window size, excluding highlight box.  */
 197   max_lines = TUI_DISASM_WIN->generic.height - 2;
 198   line_width = TUI_DISASM_WIN->generic.width - 2;
 199
 200   /* Get temporary table that will hold all strings (addr & insn).  */
 201   asm_lines = XALLOCAVEC (struct tui_asm_line, max_lines);
 202   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 203
 204   tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 205
 206   /* See what is the maximum length of an address and of a line.  */
 207   addr_size = 0;
 208   max_size = 0;
 209   for (i = 0; i < max_lines; i++)
 210     {
 211       size_t len = strlen (asm_lines[i].addr_string);
 212
 213       if (len > addr_size)
 214         addr_size = len;
 215
 216       len = strlen (asm_lines[i].insn) + tab_len;
 217       if (len > max_size)
 218         max_size = len;
 219     }
 220   max_size += addr_size + tab_len;
 221
 222   /* Allocate memory to create each line.  */
 223   line = (char*) alloca (max_size);
 224   insn_pos = (1 + (addr_size / tab_len)) * tab_len;
 225
 226   /* Now construct each line.  */
 227   for (i = 0; i < max_lines; i++)
 228     {
 229       struct tui_win_element *element;
 230       struct tui_source_element *src;
 231       int cur_len;
 232
 233       element = TUI_DISASM_WIN->generic.content[i];
 234       src = &element->which_element.source;
 235       strcpy (line, asm_lines[i].addr_string);
 236       cur_len = strlen (line);
 237       memset (line + cur_len, ' ', insn_pos - cur_len);
 238       strcpy (line + insn_pos, asm_lines[i].insn);
 239
 240       /* Now copy the line taking the offset into account.  */
 241       if (strlen (line) > offset)
 242         {
 243           strncpy (src->line, &line[offset], line_width);
 244           src->line[line_width] = '\0';
 245         }
 246       else
 247         src->line[0] = '\0';
 248
 249       src->line_or_addr.loa = LOA_ADDRESS;
 250       src->line_or_addr.u.addr = asm_lines[i].addr;
 251       src->is_exec_point = asm_lines[i].addr == cur_pc;
 252
 253       /* See whether there is a breakpoint installed.  */
 254       src->has_break = (!src->is_exec_point
 255                         && breakpoint_here_p (current_program_space->aspace,
 256                                               pc)
 257                         != no_breakpoint_here);
 258
 259       xfree (asm_lines[i].addr_string);
 260       xfree (asm_lines[i].insn);
 261     }
 262   TUI_DISASM_WIN->generic.content_size = i;
 263   return TUI_SUCCESS;
 264 }
 265
 266
 267 /* Function to display the disassembly window with disassembled code.  */
 268 void
 269 tui_show_disassem (struct gdbarch *gdbarch, CORE_ADDR start_addr)
 270 {
 271   struct symtab *s = find_pc_line_symtab (start_addr);
 272   struct tui_win_info *win_with_focus = tui_win_with_focus ();
 273   struct tui_line_or_address val;
 274
 275   val.loa = LOA_ADDRESS;
 276   val.u.addr = start_addr;
 277   tui_add_win_to_layout (DISASSEM_WIN);
 278   tui_update_source_window (TUI_DISASM_WIN, gdbarch, s, val, FALSE);
 279
 280   /* If the focus was in the src win, put it in the asm win, if the
 281      source view isn't split.  */
 282   if (tui_current_layout () != SRC_DISASSEM_COMMAND
 283       && win_with_focus == TUI_SRC_WIN)
 284     tui_set_win_focus_to (TUI_DISASM_WIN);
 285
 286   return;
 287 }
 288
 289
 290 /* Function to display the disassembly window.  */
 291 void
 292 tui_show_disassem_and_update_source (struct gdbarch *gdbarch,
 293                                      CORE_ADDR start_addr)
 294 {
 295   struct symtab_and_line sal;
 296
 297   tui_show_disassem (gdbarch, start_addr);
 298   if (tui_current_layout () == SRC_DISASSEM_COMMAND)
 299     {
 300       struct tui_line_or_address val;
 301
 302       /* Update what is in the source window if it is displayed too,
 303          note that it follows what is in the disassembly window and
 304          visa-versa.  */
 305       sal = find_pc_line (start_addr, 0);
 306       val.loa = LOA_LINE;
 307       val.u.line_no = sal.line;
 308       tui_update_source_window (TUI_SRC_WIN, gdbarch, sal.symtab, val, TRUE);
 309       if (sal.symtab)
 310         {
 311           set_current_source_symtab_and_line (&sal);
 312           tui_update_locator_fullname (symtab_to_fullname (sal.symtab));
 313         }
 314       else
 315         tui_update_locator_fullname ("?");
 316     }
 317
 318   return;
 319 }
 320
 321 void
 322 tui_get_begin_asm_address (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 323 {
 324   struct tui_gen_win_info *locator;
 325   struct tui_locator_element *element;
 326   struct gdbarch *gdbarch = get_current_arch ();
 327   CORE_ADDR addr;
 328
 329   locator = tui_locator_win_info_ptr ();
 330   element = &locator->content[0]->which_element.locator;
 331
 332   if (element->addr == 0)
 333     {
 334       struct bound_minimal_symbol main_symbol;
 335
 336       /* Find address of the start of program.
 337          Note: this should be language specific.  */
 338       main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
 339       if (main_symbol.minsym == 0)
 340         main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
 341       if (main_symbol.minsym == 0)
 342         main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
 343       if (main_symbol.minsym)
 344         addr = BMSYMBOL_VALUE_ADDRESS (main_symbol);
 345       else
 346         addr = 0;
 347     }
 348   else                          /* The target is executing.  */
 349     {
 350       gdbarch = element->gdbarch;
 351       addr = element->addr;
 352     }
 353
 354   *gdbarch_p = gdbarch;
 355   *addr_p = addr;
 356 }
 357
 358 /* Determine what the low address will be to display in the TUI's
 359    disassembly window.  This may or may not be the same as the low
 360    address input.  */
 361 CORE_ADDR
 362 tui_get_low_disassembly_address (struct gdbarch *gdbarch,
 363                                  CORE_ADDR low, CORE_ADDR pc)
 364 {
 365   int pos;
 366
 367   /* Determine where to start the disassembly so that the pc is about
 368      in the middle of the viewport.  */
 369   pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
 370   pc = tui_find_disassembly_address (gdbarch, pc, -pos);
 371
 372   if (pc < low)
 373     pc = low;
 374   return pc;
 375 }
 376
 377 /* Scroll the disassembly forward or backward vertically.  */
 378 void
 379 tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
 380                               int num_to_scroll)
 381 {
 382   if (TUI_DISASM_WIN->generic.content != NULL)
 383     {
 384       struct gdbarch *gdbarch = TUI_DISASM_WIN->detail.source_info.gdbarch;
 385       CORE_ADDR pc;
 386       tui_win_content content;
 387       struct tui_line_or_address val;
 388       int dir;
 389
 390       content = (tui_win_content) TUI_DISASM_WIN->generic.content;
 391
 392       pc = content[0]->which_element.source.line_or_addr.u.addr;
 393       num_to_scroll++;
 394       dir = (scroll_direction == FORWARD_SCROLL)
 395         ? num_to_scroll : -num_to_scroll;
 396
 397       val.loa = LOA_ADDRESS;
 398       val.u.addr = tui_find_disassembly_address (gdbarch, pc, dir);
 399       tui_update_source_window_as_is (TUI_DISASM_WIN, gdbarch,
 400                                       NULL, val, FALSE);
 401     }
 402 }