gdb/tui/tui-disasm.c

   1 /* Disassembly display.
   2
   3    Copyright (C) 1998-2017 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, insn_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   /* Determine maximum address- and instruction lengths.  */
 207   addr_size = 0;
 208   insn_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);
 217       if (len > insn_size)
 218         insn_size = len;
 219     }
 220
 221   /* Align instructions to the same column.  */
 222   insn_pos = (1 + (addr_size / tab_len)) * tab_len;
 223
 224   /* Allocate memory to create each line.  */
 225   line = (char*) alloca (insn_pos + insn_size + 1);
 226
 227   /* Now construct each line.  */
 228   for (i = 0; i < max_lines; i++)
 229     {
 230       struct tui_win_element *element;
 231       struct tui_source_element *src;
 232       int cur_len;
 233
 234       element = TUI_DISASM_WIN->generic.content[i];
 235       src = &element->which_element.source;
 236       strcpy (line, asm_lines[i].addr_string);
 237       cur_len = strlen (line);
 238       memset (line + cur_len, ' ', insn_pos - cur_len);
 239       strcpy (line + insn_pos, asm_lines[i].insn);
 240
 241       /* Now copy the line taking the offset into account.  */
 242       if (strlen (line) > offset)
 243         {
 244           strncpy (src->line, &line[offset], line_width);
 245           src->line[line_width] = '\0';
 246         }
 247       else
 248         src->line[0] = '\0';
 249
 250       src->line_or_addr.loa = LOA_ADDRESS;
 251       src->line_or_addr.u.addr = asm_lines[i].addr;
 252       src->is_exec_point = asm_lines[i].addr == cur_pc;
 253
 254       /* See whether there is a breakpoint installed.  */
 255       src->has_break = (!src->is_exec_point
 256                         && breakpoint_here_p (current_program_space->aspace,
 257                                               pc)
 258                         != no_breakpoint_here);
 259
 260       xfree (asm_lines[i].addr_string);
 261       xfree (asm_lines[i].insn);
 262     }
 263   TUI_DISASM_WIN->generic.content_size = i;
 264   return TUI_SUCCESS;
 265 }
 266
 267
 268 /* Function to display the disassembly window with disassembled code.  */
 269 void
 270 tui_show_disassem (struct gdbarch *gdbarch, CORE_ADDR start_addr)
 271 {
 272   struct symtab *s = find_pc_line_symtab (start_addr);
 273   struct tui_win_info *win_with_focus = tui_win_with_focus ();
 274   struct tui_line_or_address val;
 275
 276   val.loa = LOA_ADDRESS;
 277   val.u.addr = start_addr;
 278   tui_add_win_to_layout (DISASSEM_WIN);
 279   tui_update_source_window (TUI_DISASM_WIN, gdbarch, s, val, FALSE);
 280
 281   /* If the focus was in the src win, put it in the asm win, if the
 282      source view isn't split.  */
 283   if (tui_current_layout () != SRC_DISASSEM_COMMAND
 284       && win_with_focus == TUI_SRC_WIN)
 285     tui_set_win_focus_to (TUI_DISASM_WIN);
 286
 287   return;
 288 }
 289
 290
 291 /* Function to display the disassembly window.  */
 292 void
 293 tui_show_disassem_and_update_source (struct gdbarch *gdbarch,
 294                                      CORE_ADDR start_addr)
 295 {
 296   struct symtab_and_line sal;
 297
 298   tui_show_disassem (gdbarch, start_addr);
 299   if (tui_current_layout () == SRC_DISASSEM_COMMAND)
 300     {
 301       struct tui_line_or_address val;
 302
 303       /* Update what is in the source window if it is displayed too,
 304          note that it follows what is in the disassembly window and
 305          visa-versa.  */
 306       sal = find_pc_line (start_addr, 0);
 307       val.loa = LOA_LINE;
 308       val.u.line_no = sal.line;
 309       tui_update_source_window (TUI_SRC_WIN, gdbarch, sal.symtab, val, TRUE);
 310       if (sal.symtab)
 311         {
 312           set_current_source_symtab_and_line (&sal);
 313           tui_update_locator_fullname (symtab_to_fullname (sal.symtab));
 314         }
 315       else
 316         tui_update_locator_fullname ("?");
 317     }
 318
 319   return;
 320 }
 321
 322 void
 323 tui_get_begin_asm_address (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 324 {
 325   struct tui_gen_win_info *locator;
 326   struct tui_locator_element *element;
 327   struct gdbarch *gdbarch = get_current_arch ();
 328   CORE_ADDR addr;
 329
 330   locator = tui_locator_win_info_ptr ();
 331   element = &locator->content[0]->which_element.locator;
 332
 333   if (element->addr == 0)
 334     {
 335       struct bound_minimal_symbol main_symbol;
 336
 337       /* Find address of the start of program.
 338          Note: this should be language specific.  */
 339       main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
 340       if (main_symbol.minsym == 0)
 341         main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
 342       if (main_symbol.minsym == 0)
 343         main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
 344       if (main_symbol.minsym)
 345         addr = BMSYMBOL_VALUE_ADDRESS (main_symbol);
 346       else
 347         addr = 0;
 348     }
 349   else                          /* The target is executing.  */
 350     {
 351       gdbarch = element->gdbarch;
 352       addr = element->addr;
 353     }
 354
 355   *gdbarch_p = gdbarch;
 356   *addr_p = addr;
 357 }
 358
 359 /* Determine what the low address will be to display in the TUI's
 360    disassembly window.  This may or may not be the same as the low
 361    address input.  */
 362 CORE_ADDR
 363 tui_get_low_disassembly_address (struct gdbarch *gdbarch,
 364                                  CORE_ADDR low, CORE_ADDR pc)
 365 {
 366   int pos;
 367
 368   /* Determine where to start the disassembly so that the pc is about
 369      in the middle of the viewport.  */
 370   pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
 371   pc = tui_find_disassembly_address (gdbarch, pc, -pos);
 372
 373   if (pc < low)
 374     pc = low;
 375   return pc;
 376 }
 377
 378 /* Scroll the disassembly forward or backward vertically.  */
 379 void
 380 tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
 381                               int num_to_scroll)
 382 {
 383   if (TUI_DISASM_WIN->generic.content != NULL)
 384     {
 385       struct gdbarch *gdbarch = TUI_DISASM_WIN->detail.source_info.gdbarch;
 386       CORE_ADDR pc;
 387       tui_win_content content;
 388       struct tui_line_or_address val;
 389       int dir;
 390
 391       content = (tui_win_content) TUI_DISASM_WIN->generic.content;
 392
 393       pc = content[0]->which_element.source.line_or_addr.u.addr;
 394       num_to_scroll++;
 395       dir = (scroll_direction == FORWARD_SCROLL)
 396         ? num_to_scroll : -num_to_scroll;
 397
 398       val.loa = LOA_ADDRESS;
 399       val.u.addr = tui_find_disassembly_address (gdbarch, pc, dir);
 400       tui_update_source_window_as_is (TUI_DISASM_WIN, gdbarch,
 401                                       NULL, val, FALSE);
 402     }
 403 }