binutils-gdb/gdb/tui/tui-source.c
Patrick Palka 2eb639cbe4 TUI: avoid calling strcpy() on identical string objects
In tui_set_source_content(), when offset == 0 the source and destination
pointers of the call to strcpy() are actually the same.  In this case
not only is strcpy() unnecessary but it is also UB when the two strings
overlap.

gdb/ChangeLog:

	* tui/tui-source.c (tui_set_source_content): Avoid calling
	strcpy() when offset is 0.
2015-04-27 21:19:58 -04:00

384 lines
11 KiB
C

/* TUI display source window.
Copyright (C) 1998-2015 Free Software Foundation, Inc.
Contributed by Hewlett-Packard Company.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include <ctype.h>
#include "symtab.h"
#include "frame.h"
#include "breakpoint.h"
#include "source.h"
#include "symtab.h"
#include "objfiles.h"
#include "filenames.h"
#include "tui/tui.h"
#include "tui/tui-data.h"
#include "tui/tui-stack.h"
#include "tui/tui-winsource.h"
#include "tui/tui-source.h"
#include "gdb_curses.h"
/* Function to display source in the source window. */
enum tui_status
tui_set_source_content (struct symtab *s,
int line_no,
int noerror)
{
enum tui_status ret = TUI_FAILURE;
if (s != (struct symtab *) NULL)
{
FILE *stream;
int i, desc, c, line_width, nlines;
char *src_line = 0;
if ((ret = tui_alloc_source_buffer (TUI_SRC_WIN)) == TUI_SUCCESS)
{
line_width = TUI_SRC_WIN->generic.width - 1;
/* Take hilite (window border) into account, when
calculating the number of lines. */
nlines = (line_no + (TUI_SRC_WIN->generic.height - 2)) - line_no;
desc = open_source_file (s);
if (desc < 0)
{
if (!noerror)
{
const char *filename = symtab_to_filename_for_display (s);
char *name = alloca (strlen (filename) + 100);
sprintf (name, "%s:%d", filename, line_no);
print_sys_errmsg (name, errno);
}
ret = TUI_FAILURE;
}
else
{
if (s->line_charpos == 0)
find_source_lines (s, desc);
if (line_no < 1 || line_no > s->nlines)
{
close (desc);
printf_unfiltered ("Line number %d out of range; "
"%s has %d lines.\n",
line_no,
symtab_to_filename_for_display (s),
s->nlines);
}
else if (lseek (desc, s->line_charpos[line_no - 1], 0) < 0)
{
close (desc);
perror_with_name (symtab_to_filename_for_display (s));
}
else
{
int offset, cur_line_no, cur_line, cur_len, threshold;
struct tui_gen_win_info *locator
= tui_locator_win_info_ptr ();
struct tui_source_info *src
= &TUI_SRC_WIN->detail.source_info;
const char *s_filename = symtab_to_filename_for_display (s);
if (TUI_SRC_WIN->generic.title)
xfree (TUI_SRC_WIN->generic.title);
TUI_SRC_WIN->generic.title = xstrdup (s_filename);
xfree (src->fullname);
src->fullname = xstrdup (symtab_to_fullname (s));
/* Determine the threshold for the length of the
line and the offset to start the display. */
offset = src->horizontal_offset;
threshold = (line_width - 1) + offset;
stream = fdopen (desc, FOPEN_RT);
clearerr (stream);
cur_line = 0;
src->gdbarch = get_objfile_arch (SYMTAB_OBJFILE (s));
src->start_line_or_addr.loa = LOA_LINE;
cur_line_no = src->start_line_or_addr.u.line_no = line_no;
if (offset > 0)
src_line = (char *) xmalloc (
(threshold + 1) * sizeof (char));
while (cur_line < nlines)
{
struct tui_win_element *element
= TUI_SRC_WIN->generic.content[cur_line];
/* Get the first character in the line. */
c = fgetc (stream);
if (offset == 0)
src_line = TUI_SRC_WIN->generic.content[cur_line]
->which_element.source.line;
/* Init the line with the line number. */
sprintf (src_line, "%-6d", cur_line_no);
cur_len = strlen (src_line);
i = cur_len - ((cur_len / tui_default_tab_len ())
* tui_default_tab_len ());
while (i < tui_default_tab_len ())
{
src_line[cur_len] = ' ';
i++;
cur_len++;
}
src_line[cur_len] = (char) 0;
/* Set whether element is the execution point
and whether there is a break point on it. */
element->which_element.source.line_or_addr.loa =
LOA_LINE;
element->which_element.source.line_or_addr.u.line_no =
cur_line_no;
element->which_element.source.is_exec_point =
(filename_cmp (locator->content[0]
->which_element.locator.full_name,
symtab_to_fullname (s)) == 0
&& cur_line_no
== locator->content[0]
->which_element.locator.line_no);
if (c != EOF)
{
i = strlen (src_line) - 1;
do
{
if ((c != '\n') && (c != '\r')
&& (++i < threshold))
{
if (c < 040 && c != '\t')
{
src_line[i++] = '^';
src_line[i] = c + 0100;
}
else if (c == 0177)
{
src_line[i++] = '^';
src_line[i] = '?';
}
else
{ /* Store the charcter in the
line buffer. If it is a tab,
then translate to the correct
number of chars so we don't
overwrite our buffer. */
if (c == '\t')
{
int j, max_tab_len
= tui_default_tab_len ();
for (j = i - ((i / max_tab_len)
* max_tab_len);
j < max_tab_len
&& i < threshold;
i++, j++)
src_line[i] = ' ';
i--;
}
else
src_line[i] = c;
}
src_line[i + 1] = 0;
}
else
{ /* If we have not reached EOL, then
eat chars until we do. */
while (c != EOF && c != '\n' && c != '\r')
c = fgetc (stream);
/* Handle non-'\n' end-of-line. */
if (c == '\r'
&& (c = fgetc (stream)) != '\n'
&& c != EOF)
{
ungetc (c, stream);
c = '\r';
}
}
}
while (c != EOF && c != '\n' && c != '\r'
&& i < threshold
&& (c = fgetc (stream)));
}
/* Now copy the line taking the offset into
account. */
if (offset == 0)
;
else if (strlen (src_line) > offset)
strcpy (TUI_SRC_WIN->generic.content[cur_line]
->which_element.source.line,
&src_line[offset]);
else
TUI_SRC_WIN->generic.content[cur_line]
->which_element.source.line[0] = (char) 0;
cur_line++;
cur_line_no++;
}
if (offset > 0)
xfree (src_line);
fclose (stream);
TUI_SRC_WIN->generic.content_size = nlines;
ret = TUI_SUCCESS;
}
}
}
}
return ret;
}
/* elz: This function sets the contents of the source window to empty
except for a line in the middle with a warning message about the
source not being available. This function is called by
tui_erase_source_contents(), which in turn is invoked when the
source files cannot be accessed. */
void
tui_set_source_content_nil (struct tui_win_info *win_info,
char *warning_string)
{
int line_width;
int n_lines;
int curr_line = 0;
line_width = win_info->generic.width - 1;
n_lines = win_info->generic.height - 2;
/* Set to empty each line in the window, except for the one which
contains the message. */
while (curr_line < win_info->generic.content_size)
{
/* Set the information related to each displayed line to null:
i.e. the line number is 0, there is no bp, it is not where
the program is stopped. */
struct tui_win_element *element = win_info->generic.content[curr_line];
element->which_element.source.line_or_addr.loa = LOA_LINE;
element->which_element.source.line_or_addr.u.line_no = 0;
element->which_element.source.is_exec_point = FALSE;
element->which_element.source.has_break = FALSE;
/* Set the contents of the line to blank. */
element->which_element.source.line[0] = (char) 0;
/* If the current line is in the middle of the screen, then we
want to display the 'no source available' message in it.
Note: the 'weird' arithmetic with the line width and height
comes from the function tui_erase_source_content(). We need
to keep the screen and the window's actual contents in
synch. */
if (curr_line == (n_lines / 2 + 1))
{
int i;
int xpos;
int warning_length = strlen (warning_string);
char *src_line;
src_line = element->which_element.source.line;
if (warning_length >= ((line_width - 1) / 2))
xpos = 1;
else
xpos = (line_width - 1) / 2 - warning_length;
for (i = 0; i < xpos; i++)
src_line[i] = ' ';
sprintf (src_line + i, "%s", warning_string);
for (i = xpos + warning_length; i < line_width; i++)
src_line[i] = ' ';
src_line[i] = '\n';
} /* end if */
curr_line++;
} /* end while */
}
/* Function to display source in the source window. This function
initializes the horizontal scroll to 0. */
void
tui_show_symtab_source (struct gdbarch *gdbarch, struct symtab *s,
struct tui_line_or_address line,
int noerror)
{
TUI_SRC_WIN->detail.source_info.horizontal_offset = 0;
tui_update_source_window_as_is (TUI_SRC_WIN, gdbarch, s, line, noerror);
}
/* Answer whether the source is currently displayed in the source
window. */
int
tui_source_is_displayed (const char *fullname)
{
return (TUI_SRC_WIN != NULL
&& TUI_SRC_WIN->generic.content_in_use
&& (filename_cmp (tui_locator_win_info_ptr ()->content[0]
->which_element.locator.full_name,
fullname) == 0));
}
/* Scroll the source forward or backward vertically. */
void
tui_vertical_source_scroll (enum tui_scroll_direction scroll_direction,
int num_to_scroll)
{
if (TUI_SRC_WIN->generic.content != NULL)
{
struct tui_line_or_address l;
struct symtab *s;
tui_win_content content = (tui_win_content) TUI_SRC_WIN->generic.content;
struct symtab_and_line cursal = get_current_source_symtab_and_line ();
if (cursal.symtab == (struct symtab *) NULL)
s = find_pc_line_symtab (get_frame_pc (get_selected_frame (NULL)));
else
s = cursal.symtab;
l.loa = LOA_LINE;
if (scroll_direction == FORWARD_SCROLL)
{
l.u.line_no = content[0]->which_element.source.line_or_addr.u.line_no
+ num_to_scroll;
if (l.u.line_no > s->nlines)
/* line = s->nlines - win_info->generic.content_size + 1; */
/* elz: fix for dts 23398. */
l.u.line_no
= content[0]->which_element.source.line_or_addr.u.line_no;
}
else
{
l.u.line_no = content[0]->which_element.source.line_or_addr.u.line_no
- num_to_scroll;
if (l.u.line_no <= 0)
l.u.line_no = 1;
}
print_source_lines (s, l.u.line_no, l.u.line_no + 1, 0);
}
}