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 <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).minsym;
 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 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   tui_disassemble (gdbarch, asm_lines, pc, max_lines);
 207
 208   /* See what is the maximum length of an address and of a line.  */
 209   addr_size = 0;
 210   max_size = 0;
 211   for (i = 0; i < max_lines; i++)
 212     {
 213       size_t len = strlen (asm_lines[i].addr_string);
 214
 215       if (len > addr_size)
 216         addr_size = len;
 217
 218       len = strlen (asm_lines[i].insn) + tab_len;
 219       if (len > max_size)
 220         max_size = len;
 221     }
 222   max_size += addr_size + tab_len;
 223
 224   /* Allocate memory to create each line.  */
 225   line = (char*) alloca (max_size);
 226   insn_pos = (1 + (addr_size / tab_len)) * tab_len;
 227
 228   /* Now construct each line.  */
 229   for (i = 0; i < max_lines; i++)
 230     {
 231       struct tui_win_element *element;
 232       struct tui_source_element *src;
 233       int cur_len;
 234
 235       element = (struct tui_win_element *) TUI_DISASM_WIN->generic.content[i];
 236       src = &element->which_element.source;
 237       strcpy (line, asm_lines[i].addr_string);
 238       cur_len = strlen (line);
 239
 240       /* Add spaces to make the instructions start on the same
 241          column.  */
 242       while (cur_len < insn_pos)
 243         {
 244           strcat (line, " ");
 245           cur_len++;
 246         }
 247
 248       strcat (line, asm_lines[i].insn);
 249
 250       /* Now copy the line taking the offset into account.  */
 251       if (strlen (line) > offset)
 252         strcpy (src->line, &line[offset]);
 253       else
 254         src->line[0] = '\0';
 255
 256       src->line_or_addr.loa = LOA_ADDRESS;
 257       src->line_or_addr.u.addr = asm_lines[i].addr;
 258       src->is_exec_point = asm_lines[i].addr == cur_pc;
 259
 260       /* See whether there is a breakpoint installed.  */
 261       src->has_break = (!src->is_exec_point
 262                         && breakpoint_here_p (current_program_space->aspace,
 263                                               pc)
 264                         != no_breakpoint_here);
 265
 266       xfree (asm_lines[i].addr_string);
 267       xfree (asm_lines[i].insn);
 268     }
 269   TUI_DISASM_WIN->generic.content_size = i;
 270   return TUI_SUCCESS;
 271 }
 272
 273
 274 /* Function to display the disassembly window with disassembled code.  */
 275 void
 276 tui_show_disassem (struct gdbarch *gdbarch, CORE_ADDR start_addr)
 277 {
 278   struct symtab *s = find_pc_symtab (start_addr);
 279   struct tui_win_info *win_with_focus = tui_win_with_focus ();
 280   struct tui_line_or_address val;
 281
 282   val.loa = LOA_ADDRESS;
 283   val.u.addr = start_addr;
 284   tui_add_win_to_layout (DISASSEM_WIN);
 285   tui_update_source_window (TUI_DISASM_WIN, gdbarch, s, val, FALSE);
 286
 287   /* If the focus was in the src win, put it in the asm win, if the
 288      source view isn't split.  */
 289   if (tui_current_layout () != SRC_DISASSEM_COMMAND
 290       && win_with_focus == TUI_SRC_WIN)
 291     tui_set_win_focus_to (TUI_DISASM_WIN);
 292
 293   return;
 294 }
 295
 296
 297 /* Function to display the disassembly window.  */
 298 void
 299 tui_show_disassem_and_update_source (struct gdbarch *gdbarch,
 300                                      CORE_ADDR start_addr)
 301 {
 302   struct symtab_and_line sal;
 303
 304   tui_show_disassem (gdbarch, start_addr);
 305   if (tui_current_layout () == SRC_DISASSEM_COMMAND)
 306     {
 307       struct tui_line_or_address val;
 308
 309       /* Update what is in the source window if it is displayed too,
 310          note that it follows what is in the disassembly window and
 311          visa-versa.  */
 312       sal = find_pc_line (start_addr, 0);
 313       val.loa = LOA_LINE;
 314       val.u.line_no = sal.line;
 315       tui_update_source_window (TUI_SRC_WIN, gdbarch, sal.symtab, val, TRUE);
 316       if (sal.symtab)
 317         {
 318           set_current_source_symtab_and_line (&sal);
 319           tui_update_locator_fullname (symtab_to_fullname (sal.symtab));
 320         }
 321       else
 322         tui_update_locator_fullname ("?");
 323     }
 324
 325   return;
 326 }
 327
 328 void
 329 tui_get_begin_asm_address (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 330 {
 331   struct tui_gen_win_info *locator;
 332   struct tui_locator_element *element;
 333   struct gdbarch *gdbarch = get_current_arch ();
 334   CORE_ADDR addr;
 335
 336   locator = tui_locator_win_info_ptr ();
 337   element = &((struct tui_win_element *)
 338               locator->content[0])->which_element.locator;
 339
 340   if (element->addr == 0)
 341     {
 342       struct minimal_symbol *main_symbol;
 343
 344       /* Find address of the start of program.
 345          Note: this should be language specific.  */
 346       main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
 347       if (main_symbol == 0)
 348         main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
 349       if (main_symbol == 0)
 350         main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
 351       if (main_symbol)
 352         addr = SYMBOL_VALUE_ADDRESS (main_symbol);
 353       else
 354         addr = 0;
 355     }
 356   else                          /* The target is executing.  */
 357     {
 358       gdbarch = element->gdbarch;
 359       addr = element->addr;
 360     }
 361
 362   *gdbarch_p = gdbarch;
 363   *addr_p = addr;
 364 }
 365
 366 /* Determine what the low address will be to display in the TUI's
 367    disassembly window.  This may or may not be the same as the low
 368    address input.  */
 369 CORE_ADDR
 370 tui_get_low_disassembly_address (struct gdbarch *gdbarch,
 371                                  CORE_ADDR low, CORE_ADDR pc)
 372 {
 373   int pos;
 374
 375   /* Determine where to start the disassembly so that the pc is about
 376      in the middle of the viewport.  */
 377   pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
 378   pc = tui_find_disassembly_address (gdbarch, pc, -pos);
 379
 380   if (pc < low)
 381     pc = low;
 382   return pc;
 383 }
 384
 385 /* Scroll the disassembly forward or backward vertically.  */
 386 void
 387 tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
 388                               int num_to_scroll)
 389 {
 390   if (TUI_DISASM_WIN->generic.content != NULL)
 391     {
 392       struct gdbarch *gdbarch = TUI_DISASM_WIN->detail.source_info.gdbarch;
 393       CORE_ADDR pc;
 394       tui_win_content content;
 395       struct tui_line_or_address val;
 396       int dir;
 397
 398       content = (tui_win_content) TUI_DISASM_WIN->generic.content;
 399
 400       pc = content[0]->which_element.source.line_or_addr.u.addr;
 401       num_to_scroll++;
 402       dir = (scroll_direction == FORWARD_SCROLL)
 403         ? num_to_scroll : -num_to_scroll;
 404
 405       val.loa = LOA_ADDRESS;
 406       val.u.addr = tui_find_disassembly_address (gdbarch, pc, dir);
 407       tui_update_source_window_as_is (TUI_DISASM_WIN, gdbarch,
 408                                       NULL, val, FALSE);
 409     }
 410 }