gdb/tui/tui-disasm.c

   1 /* Disassembly display.
   2
   3    Copyright (C) 1998-2013 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 "gdb_string.h"
  31 #include "tui/tui.h"
  32 #include "tui/tui-data.h"
  33 #include "tui/tui-win.h"
  34 #include "tui/tui-layout.h"
  35 #include "tui/tui-winsource.h"
  36 #include "tui/tui-stack.h"
  37 #include "tui/tui-file.h"
  38 #include "tui/tui-disasm.h"
  39 #include "progspace.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 = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
 103                                          * max_lines);
 104   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 105
 106   new_low = pc;
 107   if (from > 0)
 108     {
 109       tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 110       new_low = asm_lines[max_lines - 1].addr;
 111     }
 112   else
 113     {
 114       CORE_ADDR last_addr;
 115       int pos;
 116       struct minimal_symbol *msymbol;
 117
 118       /* Find backward an address which is a symbol and for which
 119          disassembling from that address will fill completely the
 120          window.  */
 121       pos = max_lines - 1;
 122       do {
 123          new_low -= 1 * max_lines;
 124          msymbol = lookup_minimal_symbol_by_pc_section (new_low, 0);
 125
 126          if (msymbol)
 127             new_low = SYMBOL_VALUE_ADDRESS (msymbol);
 128          else
 129             new_low += 1 * max_lines;
 130
 131          tui_disassemble (gdbarch, asm_lines, new_low, max_lines);
 132          last_addr = asm_lines[pos].addr;
 133       } while (last_addr > pc && msymbol);
 134
 135       /* Scan forward disassembling one instruction at a time until
 136          the last visible instruction of the window matches the pc.
 137          We keep the disassembled instructions in the 'lines' window
 138          and shift it downward (increasing its addresses).  */
 139       if (last_addr < pc)
 140         do
 141           {
 142             CORE_ADDR next_addr;
 143
 144             pos++;
 145             if (pos >= max_lines)
 146               pos = 0;
 147
 148             next_addr = tui_disassemble (gdbarch, &asm_lines[pos],
 149                                          last_addr, 1);
 150
 151             /* If there are some problems while disassembling exit.  */
 152             if (next_addr <= last_addr)
 153               break;
 154             last_addr = next_addr;
 155           } while (last_addr <= pc);
 156       pos++;
 157       if (pos >= max_lines)
 158          pos = 0;
 159       new_low = asm_lines[pos].addr;
 160     }
 161   for (i = 0; i < max_lines; i++)
 162     {
 163       xfree (asm_lines[i].addr_string);
 164       xfree (asm_lines[i].insn);
 165     }
 166   return new_low;
 167 }
 168
 169 /* Function to set the disassembly window's content.  */
 170 enum tui_status
 171 tui_set_disassem_content (struct gdbarch *gdbarch, CORE_ADDR pc)
 172 {
 173   enum tui_status ret = TUI_FAILURE;
 174   int i;
 175   int offset = TUI_DISASM_WIN->detail.source_info.horizontal_offset;
 176   int line_width, max_lines;
 177   CORE_ADDR cur_pc;
 178   struct tui_gen_win_info *locator = tui_locator_win_info_ptr ();
 179   int tab_len = tui_default_tab_len ();
 180   struct tui_asm_line *asm_lines;
 181   int insn_pos;
 182   int addr_size, max_size;
 183   char *line;
 184
 185   if (pc == 0)
 186     return TUI_FAILURE;
 187
 188   ret = tui_alloc_source_buffer (TUI_DISASM_WIN);
 189   if (ret != TUI_SUCCESS)
 190     return ret;
 191
 192   TUI_DISASM_WIN->detail.source_info.gdbarch = gdbarch;
 193   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.loa = LOA_ADDRESS;
 194   TUI_DISASM_WIN->detail.source_info.start_line_or_addr.u.addr = pc;
 195   cur_pc = (CORE_ADDR) (((struct tui_win_element *)
 196                          locator->content[0])->which_element.locator.addr);
 197
 198   max_lines = TUI_DISASM_WIN->generic.height - 2;       /* Account for
 199                                                            hilite.  */
 200
 201   /* Get temporary table that will hold all strings (addr & insn).  */
 202   asm_lines = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
 203                                          * max_lines);
 204   memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
 205
 206   line_width = TUI_DISASM_WIN->generic.width - 1;
 207
 208   tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 209
 210   /* See what is the maximum length of an address and of a line.  */
 211   addr_size = 0;
 212   max_size = 0;
 213   for (i = 0; i < max_lines; i++)
 214     {
 215       size_t len = strlen (asm_lines[i].addr_string);
 216
 217       if (len > addr_size)
 218         addr_size = len;
 219
 220       len = strlen (asm_lines[i].insn) + tab_len;
 221       if (len > max_size)
 222         max_size = len;
 223     }
 224   max_size += addr_size + tab_len;
 225
 226   /* Allocate memory to create each line.  */
 227   line = (char*) alloca (max_size);
 228   insn_pos = (1 + (addr_size / tab_len)) * tab_len;
 229
 230   /* Now construct each line.  */
 231   for (i = 0; i < max_lines; i++)
 232     {
 233       struct tui_win_element *element;
 234       struct tui_source_element *src;
 235       int cur_len;
 236
 237       element = (struct tui_win_element *) TUI_DISASM_WIN->generic.content[i];
 238       src = &element->which_element.source;
 239       strcpy (line, asm_lines[i].addr_string);
 240       cur_len = strlen (line);
 241
 242       /* Add spaces to make the instructions start on the same
 243          column.  */
 244       while (cur_len < insn_pos)
 245         {
 246           strcat (line, " ");
 247           cur_len++;
 248         }
 249
 250       strcat (line, asm_lines[i].insn);
 251
 252       /* Now copy the line taking the offset into account.  */
 253       if (strlen (line) > offset)
 254         strcpy (src->line, &line[offset]);
 255       else
 256         src->line[0] = '\0';
 257
 258       src->line_or_addr.loa = LOA_ADDRESS;
 259       src->line_or_addr.u.addr = asm_lines[i].addr;
 260       src->is_exec_point = asm_lines[i].addr == cur_pc;
 261
 262       /* See whether there is a breakpoint installed.  */
 263       src->has_break = (!src->is_exec_point
 264                         && breakpoint_here_p (current_program_space->aspace,
 265                                               pc)
 266                         != no_breakpoint_here);
 267
 268       xfree (asm_lines[i].addr_string);
 269       xfree (asm_lines[i].insn);
 270     }
 271   TUI_DISASM_WIN->generic.content_size = i;
 272   return TUI_SUCCESS;
 273 }
 274
 275
 276 /* Function to display the disassembly window with disassembled code.  */
 277 void
 278 tui_show_disassem (struct gdbarch *gdbarch, CORE_ADDR start_addr)
 279 {
 280   struct symtab *s = find_pc_symtab (start_addr);
 281   struct tui_win_info *win_with_focus = tui_win_with_focus ();
 282   struct tui_line_or_address val;
 283
 284   val.loa = LOA_ADDRESS;
 285   val.u.addr = start_addr;
 286   tui_add_win_to_layout (DISASSEM_WIN);
 287   tui_update_source_window (TUI_DISASM_WIN, gdbarch, s, val, FALSE);
 288
 289   /* If the focus was in the src win, put it in the asm win, if the
 290      source view isn't split.  */
 291   if (tui_current_layout () != SRC_DISASSEM_COMMAND
 292       && win_with_focus == TUI_SRC_WIN)
 293     tui_set_win_focus_to (TUI_DISASM_WIN);
 294
 295   return;
 296 }
 297
 298
 299 /* Function to display the disassembly window.  */
 300 void
 301 tui_show_disassem_and_update_source (struct gdbarch *gdbarch,
 302                                      CORE_ADDR start_addr)
 303 {
 304   struct symtab_and_line sal;
 305
 306   tui_show_disassem (gdbarch, start_addr);
 307   if (tui_current_layout () == SRC_DISASSEM_COMMAND)
 308     {
 309       struct tui_line_or_address val;
 310
 311       /* Update what is in the source window if it is displayed too,
 312          note that it follows what is in the disassembly window and
 313          visa-versa.  */
 314       sal = find_pc_line (start_addr, 0);
 315       val.loa = LOA_LINE;
 316       val.u.line_no = sal.line;
 317       tui_update_source_window (TUI_SRC_WIN, gdbarch, sal.symtab, val, TRUE);
 318       if (sal.symtab)
 319         {
 320           set_current_source_symtab_and_line (&sal);
 321           tui_update_locator_filename (sal.symtab->filename);
 322         }
 323       else
 324         tui_update_locator_filename ("?");
 325     }
 326
 327   return;
 328 }
 329
 330 void
 331 tui_get_begin_asm_address (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 332 {
 333   struct tui_gen_win_info *locator;
 334   struct tui_locator_element *element;
 335   struct gdbarch *gdbarch = get_current_arch ();
 336   CORE_ADDR addr;
 337
 338   locator = tui_locator_win_info_ptr ();
 339   element = &((struct tui_win_element *)
 340               locator->content[0])->which_element.locator;
 341
 342   if (element->addr == 0)
 343     {
 344       struct minimal_symbol *main_symbol;
 345
 346       /* Find address of the start of program.
 347          Note: this should be language specific.  */
 348       main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
 349       if (main_symbol == 0)
 350         main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
 351       if (main_symbol == 0)
 352         main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
 353       if (main_symbol)
 354         addr = SYMBOL_VALUE_ADDRESS (main_symbol);
 355       else
 356         addr = 0;
 357     }
 358   else                          /* The target is executing.  */
 359     {
 360       gdbarch = element->gdbarch;
 361       addr = element->addr;
 362     }
 363
 364   *gdbarch_p = gdbarch;
 365   *addr_p = addr;
 366 }
 367
 368 /* Determine what the low address will be to display in the TUI's
 369    disassembly window.  This may or may not be the same as the low
 370    address input.  */
 371 CORE_ADDR
 372 tui_get_low_disassembly_address (struct gdbarch *gdbarch,
 373                                  CORE_ADDR low, CORE_ADDR pc)
 374 {
 375   int pos;
 376
 377   /* Determine where to start the disassembly so that the pc is about
 378      in the middle of the viewport.  */
 379   pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
 380   pc = tui_find_disassembly_address (gdbarch, pc, -pos);
 381
 382   if (pc < low)
 383     pc = low;
 384   return pc;
 385 }
 386
 387 /* Scroll the disassembly forward or backward vertically.  */
 388 void
 389 tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
 390                               int num_to_scroll)
 391 {
 392   if (TUI_DISASM_WIN->generic.content != NULL)
 393     {
 394       struct gdbarch *gdbarch = TUI_DISASM_WIN->detail.source_info.gdbarch;
 395       CORE_ADDR pc;
 396       tui_win_content content;
 397       struct tui_line_or_address val;
 398       int dir;
 399
 400       content = (tui_win_content) TUI_DISASM_WIN->generic.content;
 401
 402       pc = content[0]->which_element.source.line_or_addr.u.addr;
 403       num_to_scroll++;
 404       dir = (scroll_direction == FORWARD_SCROLL)
 405         ? num_to_scroll : -num_to_scroll;
 406
 407       val.loa = LOA_ADDRESS;
 408       val.u.addr = tui_find_disassembly_address (gdbarch, pc, dir);
 409       tui_update_source_window_as_is (TUI_DISASM_WIN, gdbarch,
 410                                       NULL, val, FALSE);
 411     }
 412 }