FreeChainXenon/binutils-gdb
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

gdb: fix potentially uninitialised variable

Browse source 
In commit:

  commit 037d7135de
  Date:   Mon Nov 16 11:36:56 2020 +0000

      gdb: improve command completion for 'print', 'x', and 'display'

A potential use of an uninitialised variable was introduced.  This is
fixed in this commit.

Previously when analysing /FMT strings for tab completion we
considered two possibilities, either the user has typed '/', or the
user has typed '/' followed by an alpha-numeric character, as these
are the only valid FMT string characters.

This meant that if the user type, for example '/@' and then tried to
tab complete gdb would use an uninitialised variable.

Currently only the first character after the '/' is checked to see if
it is alpha-numeric, so if a user typed '/x@@' then gdb would be happy
to treat this as a FMT string.

Given the goal of this change was primarily to allow tab completion of
symbols later in the command when a /FMT was used then I decided to
just make the /FMT skipping less smart.  Now any characters after the
'/' up to the first white space, will be treated as a FMT string.

gdb/ChangeLog:

	* printcmd.c (skip_over_slash_fmt): Reorder code to ensure in_fmt
	is always initialized.
This commit is contained in:
Andrew Burgess 2020-11-27 10:46:07 +00:00
parent b1eea24024
commit 3df8c6afdd
2 changed files with 23 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

5
gdb/ChangeLog
View file

@ -1,3 +1,8 @@
2020-11-27 Andrew Burgess <andrew.burgess@embecosm.com>
* printcmd.c (skip_over_slash_fmt): Reorder code to ensure in_fmt
is always initialized.
2020-11-26 Przemyslaw Wirkus <przemyslaw.wirkus@arm.com>
* features/aarch64-fpu.c (create_feature_aarch64_fpu): Regenerate.

25
gdb/printcmd.c
View file

@ -1258,27 +1258,38 @@ skip_over_slash_fmt (completion_tracker &tracker, const char **args)
bool in_fmt;
tracker.set_use_custom_word_point (true);
if (ISALNUM (text[1]) || ISSPACE (text[1]))
if (text[1] == '\0')
{
/* Skip over the actual format specification. */
/* The user tried to complete after typing just the '/' character
of the /FMT string. Step the completer past the '/', but we
don't offer any completions. */
in_fmt = true;
++text;
}
else
{
/* The user has typed some characters after the '/', we assume
this is a complete /FMT string, first skip over it. */
text = skip_to_space (text);
if (*text == '\0')
{
/* We're at the end of the input string. The user has typed
'/FMT' and asked for a completion. Push an empty
completion string, this will cause readline to insert a
space so the user now has '/FMT '. */
in_fmt = true;
tracker.add_completion (make_unique_xstrdup (text));
}
else
{
/* The user has already typed things after the /FMT, skip the
whitespace and return false. Whoever called this function
should then try to complete what comes next. */
in_fmt = false;
text = skip_spaces (text);
}
}
else if (text[1] == '\0')
{
in_fmt = true;
++text;
}
tracker.advance_custom_word_point_by (text - *args);
*args = text;