1/* Disassembly display.
2
3   Copyright 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
4   Foundation, Inc.
5
6   Contributed by Hewlett-Packard Company.
7
8   This file is part of GDB.
9
10   This program is free software; you can redistribute it and/or modify
11   it under the terms of the GNU General Public License as published by
12   the Free Software Foundation; either version 2 of the License, or
13   (at your option) any later version.
14
15   This program is distributed in the hope that it will be useful,
16   but WITHOUT ANY WARRANTY; without even the implied warranty of
17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18   GNU General Public License for more details.
19
20   You should have received a copy of the GNU General Public License
21   along with this program; if not, write to the Free Software
22   Foundation, Inc., 59 Temple Place - Suite 330,
23   Boston, MA 02111-1307, USA.  */
24
25#include "defs.h"
26#include "symtab.h"
27#include "breakpoint.h"
28#include "frame.h"
29#include "value.h"
30#include "source.h"
31#include "disasm.h"
32#include "gdb_string.h"
33#include "tui/tui.h"
34#include "tui/tui-data.h"
35#include "tui/tui-win.h"
36#include "tui/tui-layout.h"
37#include "tui/tui-winsource.h"
38#include "tui/tui-stack.h"
39#include "tui/tui-file.h"
40
41#include "gdb_curses.h"
42
43struct 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.  */
53static CORE_ADDR
54tui_disassemble (struct tui_asm_line* asm_lines, CORE_ADDR pc, int count)
55{
56  struct ui_file *gdb_dis_out;
57
58  /* now init the ui_file structure */
59  gdb_dis_out = tui_sfileopen (256);
60
61  /* Now construct each line */
62  for (; count > 0; count--, asm_lines++)
63    {
64      if (asm_lines->addr_string)
65        xfree (asm_lines->addr_string);
66      if (asm_lines->insn)
67        xfree (asm_lines->insn);
68
69      print_address (pc, gdb_dis_out);
70      asm_lines->addr = pc;
71      asm_lines->addr_string = xstrdup (tui_file_get_strbuf (gdb_dis_out));
72
73      ui_file_rewind (gdb_dis_out);
74
75      pc = pc + gdb_print_insn (pc, gdb_dis_out);
76
77      asm_lines->insn = xstrdup (tui_file_get_strbuf (gdb_dis_out));
78
79      /* reset the buffer to empty */
80      ui_file_rewind (gdb_dis_out);
81    }
82  ui_file_delete (gdb_dis_out);
83  return pc;
84}
85
86/* Find the disassembly address that corresponds to FROM lines
87   above or below the PC.  Variable sized instructions are taken
88   into account by the algorithm.  */
89static CORE_ADDR
90tui_find_disassembly_address (CORE_ADDR pc, int from)
91{
92  CORE_ADDR new_low;
93  int max_lines;
94  int i;
95  struct tui_asm_line* asm_lines;
96
97  max_lines = (from > 0) ? from : - from;
98  if (max_lines <= 1)
99     return pc;
100
101  asm_lines = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
102                                         * 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 (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 minimal_symbol* msymbol;
116
117      /* Find backward an address which is a symbol
118         and for which disassembling from that address will fill
119         completely the 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)
126            new_low = SYMBOL_VALUE_ADDRESS (msymbol);
127         else
128            new_low += 1 * max_lines;
129
130         tui_disassemble (asm_lines, new_low, max_lines);
131         last_addr = asm_lines[pos].addr;
132      } while (last_addr > pc && msymbol);
133
134      /* Scan forward disassembling one instruction at a time
135         until the last visible instruction of the window
136         matches the pc.  We keep the disassembled instructions
137         in the 'lines' window and shift it downward (increasing
138         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 (&asm_lines[pos], 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.  */
169enum tui_status
170tui_set_disassem_content (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 line_width, max_lines;
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.start_line_or_addr.addr = pc;
192  cur_pc = (CORE_ADDR)
193    (((struct tui_win_element *) locator->content[0])->which_element.locator.addr);
194
195  max_lines = TUI_DISASM_WIN->generic.height - 2;	/* account for hilite */
196
197  /* Get temporary table that will hold all strings (addr & insn).  */
198  asm_lines = (struct tui_asm_line*) alloca (sizeof (struct tui_asm_line)
199                                         * max_lines);
200  memset (asm_lines, 0, sizeof (struct tui_asm_line) * max_lines);
201
202  line_width = TUI_DISASM_WIN->generic.width - 1;
203
204  tui_disassemble (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      if (len > addr_size)
213        addr_size = len;
214
215      len = strlen (asm_lines[i].insn) + tab_len;
216      if (len > max_size)
217        max_size = len;
218    }
219  max_size += addr_size + tab_len;
220
221  /* Allocate memory to create each line.  */
222  line = (char*) alloca (max_size);
223  insn_pos = (1 + (addr_size / tab_len)) * tab_len;
224
225  /* Now construct each line */
226  for (i = 0; i < max_lines; i++)
227    {
228      struct tui_win_element * element;
229      struct tui_source_element* src;
230      int cur_len;
231
232      element = (struct tui_win_element *) TUI_DISASM_WIN->generic.content[i];
233      src = &element->which_element.source;
234      strcpy (line, asm_lines[i].addr_string);
235      cur_len = strlen (line);
236
237      /* Add spaces to make the instructions start on the same column */
238      while (cur_len < insn_pos)
239        {
240          strcat (line, " ");
241          cur_len++;
242        }
243
244      strcat (line, asm_lines[i].insn);
245
246      /* Now copy the line taking the offset into account */
247      if (strlen (line) > offset)
248        strcpy (src->line, &line[offset]);
249      else
250        src->line[0] = '\0';
251
252      src->line_or_addr.addr = asm_lines[i].addr;
253      src->is_exec_point = asm_lines[i].addr == cur_pc;
254
255      /* See whether there is a breakpoint installed.  */
256      src->has_break = (!src->is_exec_point
257                       && breakpoint_here_p (pc) != 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.   */
268void
269tui_show_disassem (CORE_ADDR start_addr)
270{
271  struct symtab *s = find_pc_symtab (start_addr);
272  struct tui_win_info * win_with_focus = tui_win_with_focus ();
273  union tui_line_or_address val;
274
275  val.addr = start_addr;
276  tui_add_win_to_layout (DISASSEM_WIN);
277  tui_update_source_window (TUI_DISASM_WIN, s, val, FALSE);
278  /*
279     ** if the focus was in the src win, put it in the asm win, if the
280     ** source view isn't split
281   */
282  if (tui_current_layout () != SRC_DISASSEM_COMMAND && win_with_focus == TUI_SRC_WIN)
283    tui_set_win_focus_to (TUI_DISASM_WIN);
284
285  return;
286}
287
288
289/* Function to display the disassembly window.   */
290void
291tui_show_disassem_and_update_source (CORE_ADDR start_addr)
292{
293  struct symtab_and_line sal;
294
295  tui_show_disassem (start_addr);
296  if (tui_current_layout () == SRC_DISASSEM_COMMAND)
297    {
298      union tui_line_or_address val;
299
300      /*
301         ** Update what is in the source window if it is displayed too,
302         ** note that it follows what is in the disassembly window and visa-versa
303       */
304      sal = find_pc_line (start_addr, 0);
305      val.line_no = sal.line;
306      tui_update_source_window (TUI_SRC_WIN, sal.symtab, val, TRUE);
307      if (sal.symtab)
308	{
309	  set_current_source_symtab_and_line (&sal);
310	  tui_update_locator_filename (sal.symtab->filename);
311	}
312      else
313	tui_update_locator_filename ("?");
314    }
315
316  return;
317}
318
319CORE_ADDR
320tui_get_begin_asm_address (void)
321{
322  struct tui_gen_win_info * locator;
323  struct tui_locator_element * element;
324  CORE_ADDR addr;
325
326  locator = tui_locator_win_info_ptr ();
327  element = &((struct tui_win_element *) locator->content[0])->which_element.locator;
328
329  if (element->addr == 0)
330    {
331      struct minimal_symbol *main_symbol;
332
333      /* Find address of the start of program.
334         Note: this should be language specific.  */
335      main_symbol = lookup_minimal_symbol ("main", NULL, NULL);
336      if (main_symbol == 0)
337        main_symbol = lookup_minimal_symbol ("MAIN", NULL, NULL);
338      if (main_symbol == 0)
339        main_symbol = lookup_minimal_symbol ("_start", NULL, NULL);
340      if (main_symbol)
341        addr = SYMBOL_VALUE_ADDRESS (main_symbol);
342      else
343        addr = 0;
344    }
345  else				/* the target is executing */
346    addr = element->addr;
347
348  return addr;
349}
350
351/* Determine what the low address will be to display in the TUI's
352   disassembly window.  This may or may not be the same as the
353   low address input.  */
354CORE_ADDR
355tui_get_low_disassembly_address (CORE_ADDR low, CORE_ADDR pc)
356{
357  int pos;
358
359  /* Determine where to start the disassembly so that the pc is about in the
360     middle of the viewport.  */
361  pos = tui_default_win_viewport_height (DISASSEM_WIN, DISASSEM_COMMAND) / 2;
362  pc = tui_find_disassembly_address (pc, -pos);
363
364  if (pc < low)
365    pc = low;
366  return pc;
367}
368
369/* Scroll the disassembly forward or backward vertically.  */
370void
371tui_vertical_disassem_scroll (enum tui_scroll_direction scroll_direction,
372			      int num_to_scroll)
373{
374  if (TUI_DISASM_WIN->generic.content != NULL)
375    {
376      CORE_ADDR pc;
377      tui_win_content content;
378      struct symtab *s;
379      union tui_line_or_address val;
380      int max_lines, dir;
381      struct symtab_and_line cursal = get_current_source_symtab_and_line ();
382
383      content = (tui_win_content) TUI_DISASM_WIN->generic.content;
384      if (cursal.symtab == (struct symtab *) NULL)
385	s = find_pc_symtab (get_frame_pc (deprecated_selected_frame));
386      else
387	s = cursal.symtab;
388
389      /* account for hilite */
390      max_lines = TUI_DISASM_WIN->generic.height - 2;
391      pc = content[0]->which_element.source.line_or_addr.addr;
392      dir = (scroll_direction == FORWARD_SCROLL) ? max_lines : - max_lines;
393
394      val.addr = tui_find_disassembly_address (pc, dir);
395      tui_update_source_window_as_is (TUI_DISASM_WIN, s, val, FALSE);
396    }
397}
398