Commit Graph

817 Commits

Author SHA1 Message Date
Tom Tromey
0426ad513f Unify gdb puts functions
Now that filtered and unfiltered output can be treated identically, we
can unify the puts family of functions.  This is done under the name
"gdb_puts".  Most of this patch was written by script.
2022-03-29 12:46:24 -06:00
Tom Tromey
19a7b8ab87 Unify vprintf functions
Now that filtered and unfiltered output can be treated identically, we
can unify the vprintf family of functions: vprintf_filtered,
vprintf_unfiltered, vfprintf_filtered and vfprintf_unfiltered.  (For
the gdb_stdout variants, recall that only printf_unfiltered gets truly
unfiltered output at this point.)  This removes one such function and
renames the remaining two to "gdb_vprintf".  All callers are updated.
Much of this patch was written by script.
2022-03-29 12:46:24 -06:00
Tom Tromey
3cd5229387 Change the pager to a ui_file
This rewrites the output pager as a ui_file implementation.

A new header is introduced to declare the pager class.  The
implementation remains in utils.c for the time being, because there
are some static globals there that must be used by this code.  (This
could be cleaned up at some future date.)

I went through all the text output in gdb to ensure that this change
should be ok.  There are a few cases:

* Any existing call to printf_unfiltered is required to be avoid the
  pager.  This is ensured directly in the implementation.

* All remaining calls to the f*_unfiltered functions -- the ones that
  take an explicit ui_file -- either send to an unfiltered stream
  (e.g., gdb_stderr), which is obviously ok; or conditionally send to
  gdb_stdout

  I investigated all such calls by searching for:

    grep -e '\bf[a-z0-9_]*_unfiltered' *.[chyl] */*.[ch] | grep -v gdb_stdlog | grep -v gdb_stderr

  This yields a number of candidates to check.

  * The breakpoint _print_recreate family, and
    save_trace_state_variables.  These are used for "save" commands
    and so are fine.

  * Things printing to a temporary stream.  Obviously ok.

  * Disassembly selftests.

  * print_gdb_help - this is non-obvious, but ok because paging isn't
    yet enabled at this point during startup.

  * serial.c - doens't use gdb_stdout

  * The code in compile/.  This is all printing to a file.

  * DWARF DIE dumping - doesn't reference gdb_stdout.

* Calls to the _filtered form -- these are all clearly ok, because if
  they are using gdb_stdout, then filtering will still apply; and if
  not, then filtering never applied and still will not.

Therefore, at this point, there is no longer any distinction between
all the other _filtered and _unfiltered calls, and they can be
unified.

In this patch, take special note of the vfprintf_maybe_filtered and
ui_file::vprintf change.  This is one instance of the above idea,
erasing the distinction between filtered and unfiltered -- in this
part of the change, the "unfiltered_output" flag is never passe to
cli_ui_out.  Subsequent patches will go much further in this
direction.

Also note the can_emit_style_escape changes in ui-file.c.  Checking
against gdb_stdout or gdb_stderr was always a bit of a hack; and now
it is no longer needed, because this is decision can be more fully
delegated to the particular ui_file implementation.

ui_file::can_page is removed, because this patch removed the only call
to it.

I think this is the main part of fixing PR cli/7234.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=7234
2022-03-29 12:46:24 -06:00
Tom Tromey
52a4a5885a Switch gdb_stdlog to use timestamped_file
Currently, timestamps for logging are done by looking for the use of
gdb_stdlog in vfprintf_unfiltered.  This seems potentially buggy, in
that during logging or other redirects (like execute_fn_to_ui_file) we
might have gdb_stdout==gdb_stdlog and so, conceivably, wind up with
timestamps in a log when they were not desired.

It seems better, instead, for timestamps to be a property of the
ui_file itself.

This patch changes gdb to use the new timestamped_file for gdb_stdlog
where appropriate, and removes the special case from
vfprintf_unfiltered.

Note that this may somewhat change the output in some cases -- in
particular, when going through execute_fn_to_ui_file (or the _string
variant), timestamps won't be emitted.  This could be fixed in those
functions, but it wasn't clear to me whether this is really desirable.

Note also that this changes the TUI to send gdb_stdlog to gdb_stderr.
I imagine that the previous use of gdb_stdout here was inadvertent.
(And in any case it probably doesn't matter.)
2022-03-28 14:13:28 -06:00
Tom Tromey
8b1931b394 Use unique_ptr in CLI logging code
This changes the CLI logging code to avoid manual memory management
(to the extent possible) by using unique_ptr in a couple of spots.
This will come in handy in a later patch.
2022-03-28 14:13:28 -06:00
Tom Tromey
22f8b65e9b Simplify the CLI set_logging logic
The CLI's set_logging logic seemed unnecessarily complicated to me.
This patch simplifies it, with an eye toward changing it to use RAII
objects in a subsequent patch.

I did not touch the corresponding MI code.  That code seems incorrect
(nothing ever uses raw_stdlog, and nothing ever sets
saved_raw_stdlog).  I didn't attempt to fix this, because I question
whether this is even useful for MI.
2022-03-28 14:13:27 -06:00
Andrew Burgess
e867795e8b gdb: use python to colorize disassembler output
This commit adds styling support to the disassembler output, as such
two new commands are added to GDB:

  set style disassembler enabled on|off
  show style disassembler enabled

In this commit I make use of the Python Pygments package to provide
the styling.  I did investigate making use of libsource-highlight,
however, I found the highlighting results to be inferior to those of
Pygments; only some mnemonics were highlighted, and highlighting of
register names such as r9d and r8d (on x86-64) was incorrect.

To enable disassembler highlighting via Pygments, I've added a new
extension language hook, which is then implemented for Python.  This
hook is very similar to the existing hook for source code
colorization.

One possibly odd choice I made with the new hook is to pass a
gdb.Architecture through, even though this is currently unused.  The
reason this argument is not used is that, currently, styling is
performed identically for all architectures.

However, even though the Python function used to perform styling of
disassembly output is not part of any documented API, I don't want
to close the door on a user overriding this function to provide
architecture specific styling.  To do this, the user would inevitably
require access to the gdb.Architecture, and so I decided to add this
field now.

The styling is applied within gdb_disassembler::print_insn, to achieve
this, gdb_disassembler now writes its output into a temporary buffer,
styling is then applied to the contents of this buffer.  Finally the
gdb_disassembler buffer is copied out to its final destination stream.

There's a new test to check that the disassembler output includes some
escape sequences, though I don't check for specific colours; the
precise colors will depend on which instructions are in the
disassembler output, and, I guess, how pygments is configured.

The only negative change with this commit is how we currently style
addresses in GDB.

Currently, when the disassembler wants to print an address, we call
back into GDB, and GDB prints the address value using the `address`
styling, and the symbol name using `function` styling.  After this
commit, if pygments is used, then all disassembler styling is done
through pygments, and this include the address and symbol name parts
of the disassembler output.

I don't know how much of an issue this will be for people.  There's
already some precedent for this in GDB when we look at source styling.
For example, function names in styled source listings are not styled
using the `function` style, but instead, either GNU Source Highlight,
or pygments gets to decide how the function name should be styled.

If the Python pygments library is not present then GDB will continue
to behave as it always has, the disassembler output is mostly
unstyled, but the address and symbols are styled using the `address`
and `function` styles, as they are today.

However, if the user does `set style disassembler enabled off`, then
all disassembler styling is switched off.  This obviously covers the
use of pygments, but also includes the minimal styling done by GDB
when pygments is not available.
2022-02-14 09:53:04 +00:00
Lancelot SIX
573269a87c gdb: make thread_info::m_thread_fsm a std::unique_ptr
While working on function calls, I realized that the thread_fsm member
of struct thread_info is a raw pointer to a resource it owns.  This
commit changes the type of the thread_fsm member to a std::unique_ptr in
order to signify this ownership relationship and slightly ease resource
management (no need to manually call delete).

To ensure consistent use, the field is made a private member
(m_thread_fsm).  The setter method (set_thread_fsm) can then check
that it is incorrect to associate a FSM to a thread_info object if
another one is already in place.  This is ensured by an assertion.

The function run_inferior_call takes an argument as a pointer to a
call_thread_fsm and installs it in it in a thread_info instance.  Also
change this function's signature to accept a unique_ptr in order to
signify that the ownership of the call_thread_fsm is transferred during
the call.

No user visible change expected after this commit.

Tested on x86_64-linux with no regression observed.

Change-Id: Ia1224f72a4afa247801ce6650ce82f90224a9ae8
2022-02-07 06:12:06 -05:00
Tankut Baris Aktemur
61fb73769a gdb: add the 'set/show suppress-cli-notifications' command
GDB already has a flag to suppress printing notification events, such
as thread and inferior context switches, on the CLI.  This is used
internally when executing commands.  Make the flag available to the
user via a new command.  This is expected to be useful in scripts.

For instance, suppose that when Inferior 1 gets to a certain state,
you want to add and set up a new inferior using the commands below,
but you also want to have a reduced/clean output.

  define do-setup
    printf "Setting up Inferior 2...\n"
    add-inferior -exec a.out
    inferior 2
    break file.c:3
    run
    inferior 1
    printf "Done\n"
  end

Currently, GDB prints

  (gdb) do-setup
  Setting up Inferior 2...
  [New inferior 2]
  Added inferior 2 on connection 1 (native)
  [Switching to inferior 2 [<null>] (/tmp/a.out)]
  Breakpoint 2 at 0x1155: file file.c, line 3.

  Thread 2.1 "a.out" hit Breakpoint 2, main () at file.c:3
  3         return 0;
  [Switching to inferior 1 [process 7670] (/tmp/test)]
  [Switching to thread 1.1 (process 7670)]
  #0  main () at test.c:2
  2         int a = 1;
  Done

GDB's Python API make it possible to capture and return GDB's output,
but this does not work for all the streams.  In particular, CLI
notification events are not captured:

  (gdb) python gdb.execute("do-setup", False, True)
  [Switching to inferior 2 [<null>] (/tmp/a.out)]

  Thread 2.1 "a.out" hit Breakpoint 2, main () at file.c:3
  3         return 0;
  [Switching to inferior 1 [process 8263] (/tmp/test)]
  [Switching to thread 1.1 (process 8263)]
  #0  main () at test.c:2
  2         int a = 1;

You can use the new "set suppress-cli-notifications" command to
suppress the output:

  (gdb) set suppress-cli-notifications on
  (gdb) do-setup
  Setting up Inferior 2...
  [New inferior 2]
  Added inferior 2 on connection 1 (native)
  Breakpoint 2 at 0x1155: file file.c, line 3.
  Done
2022-02-07 08:26:56 +01:00
Tankut Baris Aktemur
2b826f7592 gdb/cli: add a 'normal_stop' option to 'cli_suppress_notification'
Extend the 'cli_suppress_notification' struct with a new field,
'normal_stop', that can be used for checking if printing normal stop
events on the CLI should be suppressed.

This patch only introduces the flag.  The subsequent patch adds a user
command to turn the flag off/on.
2022-02-07 08:26:56 +01:00
Tankut Baris Aktemur
f36c891801 gdb/cli: convert cli_suppress_notification from int to bool
Convert the suppress_notification flag for the CLI from int to bool.
2022-02-07 08:26:55 +01:00
Simon Marchi
3574a7b3f1 gdb: remove SYMTAB_DIRNAME macro
Remove the macro, replace with an equivalent method.

Change-Id: I46ec36b91bb734331138eb9cd086b2db01635aed
2022-02-06 16:03:46 -05:00
Simon Marchi
652099717d gdb: remove SYMTAB_OBJFILE macro
Remove the macro, replace with an equivalent method.

Change-Id: I8f9ecd290ad28502e53c1ceca5006ba78bf042eb
2022-02-06 16:03:46 -05:00
Andrew Burgess
82d0a72cdc gdb: handle calls to edit command passing only a linespec condition
While working on the previous commit to fix PR cli/28665, I noticed
that the 'edit' command would suffer from the same problem.  That is,
something like:

  (gdb) edit task 123

would cause GDB to break.  For a full explanation of what's going on
here, see the commit message for the previous commit.

As with the previous commit, this issue can be prevented by detecting,
and throwing, a junk at the end of the line error earlier, before
calling decode_line_1.

So, that's what this commit does.  I've also added some tests for this
issue.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28665
2022-02-02 16:27:36 +00:00
Andrew Burgess
3c5fcec6dc gdb: handle calls to list command passing only a linespec condition
In PR cli/28665, it was reported that GDB would crash when given a
command like:

  (gdb) list task 123

The problem here is that in cli/cli-cmd.c:list_command, the string
'task 123' is passed to string_to_event_location in find a location
specification.  However, this location parsing understands about
breakpoint conditions, and so, will stop parsing when it sees
something that looks like a condition, in this case, the 'task 123'
looks like a breakpoint condition.

As a result, the location we get back from string_to_event_location
has no actual location specification attached to it.  The actual call
path is:

  list_command
    string_to_event_location
      string_to_event_location_basic
        new_linespec_location

In new_linespec_location we call linespec_lex_to_end, which looks at
'task 123' and decides that there's nothing there that describes a
location.  As such, in new_linespec_location, the spec_string field of
the location is left as nullptr.

Back in list_command we then call decode_line_1, which calls
event_location_to_sals, which calls parse_linespec, which takes the
spec_string we found earlier, and tries to converts this into a list
of sals.

However, parse_linespec is not intended to be passed a nullptr, for
example, calling is_ada_operator will try to access through the
nullptr, causing undefined behaviour.  But there are other cases
within parse_linespec which don't expect to see a nullptr.

When looking at how to fix this issue, I first considered having
linespec_lex_to_end detect the problem.  That function understands
when the first thing in the linespec is a condition keyword, and so,
could throw an error saying something like: "no linespec before
condition keyword", however, this is not going to work, at least, not
without additional changes to GDB, it is valid to place a breakpoint
like:

  (gdb) break task 123

This will place a breakpoint at the current location with the
condition 'task 123', and changing linespec_lex_to_end breaks this
behaviour.

So, next, I considered what would happen if I added a condition to an
otherwise valid list command, this is what I see:

  (gdb) list file.c:1 task 123
  Junk at end of line specification.
  (gdb)

So, then I wondered, could we just pull the "Junk" detection forward,
so that we throw the error earlier, before we call decode_line_1?

It turns out that yes we can.  Well, sort of.

It is simpler, I think, to add a separate check into the list_command
function, after calling string_to_event_location, but before calling
decode_line_1.  We know when we call string_to_event_location that the
string in question is not empty, so, after calling
string_to_event_location, if non of the string has been consumed, then
the content of the string must be junk - it clearly doesn't look like
a location specification.

I've reused the same "Junk at end of line specification." error for
consistency, and added a few tests to cover this issue.

While the first version of this patch was on the mailing list, a
second bug PR gdb/28797 was raised.  This was for a very similar
issue, but this time the problem command was:

  (gdb) list ,,

Here the list command understands about the first comma, list can have
two arguments separated by a comma, and the first argument can be
missing.  So we end up trying to parse the second command "," as a
linespec.

However, in linespec_lex_to_end, we will stop parsing a linespec at a
comma, so, in the above case we end up with an empty linespec (between
the two commas), and, like above, this results in the spec_string
being nullptr.

As with the previous case, I've resolved this issue by adding an extra
check for junk at the end of the line - after parsing (or failing to
parse) the nothing between the two commas, we still have the "," left
at the end of the list command line - when we see this we can throw
the same "junk at the end of the line" error, and all is good.

I've added tests for this case too.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28665
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28797
2022-02-02 16:27:36 +00:00
Tom Tromey
1285ce8629 Always call the wrap_here method
This changes all existing calls to wrap_here to call the method on the
appropriate ui_file instead.  The choice of ui_file is determined by
context.
2022-01-26 15:19:13 -07:00
Tom Tromey
6c92c33953 Convert wrap_here to use integer parameter
I think it only really makes sense to call wrap_here with an argument
consisting solely of spaces.  Given this, it seemed better to me that
the argument be an int, rather than a string.  This patch is the
result.  Much of it was written by a script.
2022-01-26 15:19:13 -07:00
Andrew Burgess
bbea680797 gdb/python: improve the auto help text for gdb.Parameter
This commit attempts to improve the help text that is generated for
gdb.Parameter objects when the user fails to provide their own
documentation.

Documentation for a gdb.Parameter is currently pulled from two
sources: the class documentation string, and the set_doc/show_doc
class attributes.  Thus, a fully documented parameter might look like
this:

  class Param_All (gdb.Parameter):
     """This is the class documentation string."""

     show_doc = "Show the state of this parameter"
     set_doc = "Set the state of this parameter"

     def get_set_string (self):
        val = "on"
        if (self.value == False):
           val = "off"
        return "Test Parameter has been set to " + val

     def __init__ (self, name):
        super (Param_All, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN)
        self._value = True

  Param_All ('param-all')

Then in GDB we see this:

  (gdb) help set param-all
  Set the state of this parameter
  This is the class documentation string.

Which is fine.  But, if the user skips both of the documentation parts
like this:

  class Param_None (gdb.Parameter):

     def get_set_string (self):
        val = "on"
        if (self.value == False):
           val = "off"
        return "Test Parameter has been set to " + val

     def __init__ (self, name):
        super (Param_None, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN)
        self._value = True

  Param_None ('param-none')

Now in GDB we see this:

  (gdb) help set param-none
  This command is not documented.
  This command is not documented.

That's not great, the duplicated text looks a bit weird.  If we drop
different parts we get different results.  Here's what we get if the
user drops the set_doc and show_doc attributes:

  (gdb) help set param-doc
  This command is not documented.
  This is the class documentation string.

That kind of sucks, we say it's undocumented, then proceed to print
the documentation.  Finally, if we drop the class documentation but
keep the set_doc and show_doc:

  (gdb) help set param-set-show
  Set the state of this parameter
  This command is not documented.

That seems OK.

So, I think there's room for improvement.

With this patch, for the four cases above we now see this:

  # All values provided by the user, no change in this case:
  (gdb) help set param-all
  Set the state of this parameter
  This is the class documentation string.

  # Nothing provided by the user, the first string is now different:
  (gdb) help set param-none
  Set the current value of 'param-none'.
  This command is not documented.

  # Only the class documentation is provided, the first string is
  # changed as in the previous case:
  (gdb) help set param-doc
  Set the current value of 'param-doc'.
  This is the class documentation string.

  # Only the set_doc and show_doc are provided, this case is unchanged
  # from before the patch:
  (gdb) help set param-set-show
  Set the state of this parameter
  This command is not documented.

The one place where this change might be considered a negative is when
dealing with prefix commands.  If we create a prefix command but don't
supply the set_doc / show_doc strings, then this is what we saw before
my patch:

  (gdb) python Param_None ('print param-none')
  (gdb) help set print
  set print, set pr, set p
  Generic command for setting how things print.

  List of set print subcommands:

  ... snip ...
  set print param-none -- This command is not documented.
  ... snip ...

And after my patch:

  (gdb) python Param_None ('print param-none')
  (gdb) help set print
  set print, set pr, set p
  Generic command for setting how things print.

  List of set print subcommands:

  ... snip ...
  set print param-none -- Set the current value of 'print param-none'.
  ... snip ...

This seems slightly less helpful than before, but I don't think its
terrible.

Additionally, I've changed what we print when the get_show_string
method is not provided in Python.

Back when gdb.Parameter was first added to GDB, we didn't provide a
show function when registering the internal command object within
GDB.  As a result, GDB would make use of its "magic" mangling of the
show_doc string to create a sentence that would display the current
value (see deprecated_show_value_hack in cli/cli-setshow.c).

However, when we added support for the get_show_string method to
gdb.Parameter, there was an attempt to maintain backward compatibility
by displaying the show_doc string with the current value appended, see
get_show_value in py-param.c.  Unfortunately, this isn't anywhere
close to what deprecated_show_value_hack does, and the results are
pretty poor, for example, this is GDB before my patch:

  (gdb) show param-none
  This command is not documented. off

I think we can all agree that this is pretty bad.

After my patch, we how show this:

  (gdb) show param-none
  The current value of 'param-none' is "off".

Which at least is a real sentence, even if it's not very informative.

This patch does change the way that the Python API behaves slightly,
but only in the cases when the user has missed providing GDB with some
information.  In most cases I think the new behaviour is a lot better,
there's the one case (noted above) which is a bit iffy, but I think is
still OK.

I've updated the existing gdb.python/py-parameter.exp test to cover
the modified behaviour.

Finally, I've updated the documentation to (I hope) make it clearer
how the various bits of help text come together.
2022-01-26 22:00:20 +00:00
Simon Marchi
5d10a2041e gdb: add string_file::release method
A common pattern for string_file is to want to move out the internal
string buffer, because it is the result of the computation that we want
to return.  It is the reason why string_file::string returns a non-const
reference, as explained in the comment.  I think it would make sense to
have a dedicated method for that instead and make string_file::string
return a const reference.

This allows removing the explicit std::move in the typical case.  Note
that compile_program::compute was missing a move, meaning that the
resulting string was copied.  With the new version, it's not possible to
forget to move.

Change-Id: Ieaefa35b73daa7930b2f3a26988b6e3b4121bb79
2022-01-26 10:01:40 -05:00
Tom Tromey
dedb7102b3 Fix another crash with gdb parameters in Python
While looking into the language-capturing issue, I found another way
to crash gdb using parameters from Python:

(gdb) python print(gdb.parameter('endian'))

(This is related to PR python/12188, though this patch isn't going to
fix what that bug is really about.)

The problem here is that the global variable that underlies the
"endian" parameter is initialized to NULL.  However, that's not a
valid value for an "enum" set/show parameter.

My understanding is that, in gdb, an "enum" parameter's underlying
variable must have a value that is "==" (not just strcmp-equal) to one
of the values coming from the enum array.  This invariant is relied on
in various places.

I started this patch by fixing the problem with "endian".  Then I
added some assertions to add_setshow_enum_cmd to try to catch other
problems of the same type.

This patch fixes all the problems that I found.  I also looked at all
the calls to add_setshow_enum_cmd to ensure that they were all
included in the gdb I tested.  I think they are: there are no calls in
nat-* files, or in remote-sim.c; and I was trying a build with all
targets, Python, and Guile enabled.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=12188
2022-01-26 06:49:51 -07:00
Tom Tromey
d322d6d69d Move gdb_regex to gdbsupport
This moves the gdb_regex convenience class to gdbsupport.
2022-01-18 10:14:43 -07:00
Tom Tromey
7904e9613e Move gdb_argv to gdbsupport
This moves the gdb_argv class to a new header in gdbsupport.
2022-01-18 10:14:42 -07:00
Tom Tromey
b58f47ab4c Use filtered output in ordinary commands
Many otherwise ordinary commands choose to use unfiltered output
rather than filtered.  I don't think there's any reason for this, so
this changes many such commands to use filtered output instead.

Note that complete_command is not touched due to a comment there
explaining why unfiltered output is believed to be used.
2022-01-05 11:36:33 -07:00
Tom Tromey
63a8c05f09 Simplify execute_control_commands_to_string
execute_control_commands_to_string can be rewritten in terms of
execute_fn_to_string, which consolidates some knowledge about which
streams to redirect.

Regression tested on x86-64 Fedora 34.
2022-01-05 10:19:45 -07:00
Tom de Vries
f1e044bbb6 [gdb/build] Fix build breaker in gdb/cli/cli-logging.c
Fix build breaker in gdb/cli/cli-logging.c:
...
gdb/cli/cli-logging.c: In function \
  ‘void show_logging_enabled(ui_file*, int, cmd_list_element*, const char*)’:
gdb/gdbsupport/gdb_locale.h:28:28: error: cannot convert ‘char*’ to ‘ui_file*’
   28 | # define _(String) gettext (String)
      |                    ~~~~~~~~^~~~~~~~
      |                            |
      |                            char*
gdb/cli/cli-logging.c:202:25: note: in expansion of macro ‘_’
  202 |     fprintf_unfiltered (_("on: Logging is enabled.\n"));
      |                         ^
...

Build and tested on x86_64-linux.

Fixes: 45aec4e5ed ("[gdb/cli] Improve show logging output")
2022-01-04 10:24:36 +01:00
Tom de Vries
45aec4e5ed [gdb/cli] Improve show logging output
Before commit 3b6acaee89 "Update more calls to add_prefix_cmd" we had the
following output for "show logging":
...
$ gdb -q -batch -ex "set trace-commands on" \
    -ex "set logging off" \
    -ex "show logging" \
    -ex "set logging on" \
    -ex "show logging"
+set logging off
+show logging
Future logs will be written to gdb.txt.
Logs will be appended to the log file.
Output will be logged and displayed.
Debug output will be logged and displayed.
+set logging on
+show logging
Currently logging to "gdb.txt".
Logs will be appended to the log file.
Output will be logged and displayed.
Debug output will be logged and displayed.
...

After that commit we have instead:
...
+set logging off
+show logging
debugredirect:  The logging output mode is off.
file:  The current logfile is "gdb.txt".
overwrite:  Whether logging overwrites or appends to the log file is off.
redirect:  The logging output mode is off.
+set logging on
+show logging
debugredirect:  The logging output mode is off.
file:  The current logfile is "gdb.txt".
overwrite:  Whether logging overwrites or appends to the log file is off.
redirect:  The logging output mode is off.
...
which gives less clear output for some subcommands.

OTOH, it's explicit about whether boolean values are on or off.

The new text seems to have been chosen to match the set/show help texts:
...
(gdb) help show logging
Show logging options.

List of show logging subcommands:

show logging debugredirect -- Show the logging debug output mode.
show logging file -- Show the current logfile.
show logging overwrite -- \
  Show whether logging overwrites or appends to the log file.
show logging redirect -- Show the logging output mode.
...

Make the show logging messages more clear, while still keep the boolean
values explicit, such that we have:
...
$ ./gdb.sh -q -batch -ex "show logging"
logging debugredirect:  off: \
  Debug output will go to both the screen and the log file.
logging enabled:  off: Logging is disabled.
logging file:  The current logfile is "gdb.txt".
logging overwrite:  off: Logging appends to the log file.
logging redirect:  off: Output will go to both the screen and the log file.
...

Tested on x86_64-linux.
2022-01-03 23:59:30 +01:00
Joel Brobecker
4a94e36819 Automatic Copyright Year update after running gdb/copyright.py
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.

For the avoidance of doubt, all changes in this commits were
performed by the script.
2022-01-01 19:13:23 +04:00
Tom Tromey
3de0d96078 Use filtered output in show callbacks
"show" command callbacks, like most ordinary gdb commands, should use
filtered output.  I found a few that did not, so this patch changes
them to use the filtered form.
2021-12-29 11:08:14 -07:00
Tom Tromey
7514a66128 Consistently Use ui_file parameter to show callbacks
I happened to notice that one "show" callback was printing to
gdb_stdout rather than to the passed-in ui_file parameter.  I went
through all such callbacks and fixed them to consistently use the
ui_file.

Regression tested on x86-64 Fedora 34.
2021-12-29 11:08:04 -07:00
Enze Li
fa8f0a0ff0 gdb: add "exit" command as an alias for "quit"
This command adds the "exit" command as an alias for the "quit"
command, as requested in PR gdb/28406.

The documentation is also updated to mention this new command.

Tested on x86_64-linux.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28406
2021-12-18 15:19:12 +04:00
Simon Marchi
e34e391824 gdb: don't show deprecated aliases
I don't think it's very useful to show deprecated aliases to the
user.  It encourages the user to use them, when the goal is the
opposite.

For example, before:

    (gdb) help set index-cache enabled
    set index-cache enabled, set index-cache off, set index-cache on
      alias set index-cache off = set index-cache enabled off
      alias set index-cache on = set index-cache enabled on
    Enable the index cache.
    When on, enable the use of the index cache.

    (gdb) help set index-cache on
    Warning: 'set index-cache on', an alias for the command 'set index-cache enabled', is deprecated.
    Use 'set index-cache enabled on'.

    set index-cache enabled, set index-cache off, set index-cache on
      alias set index-cache off = set index-cache enabled off
      alias set index-cache on = set index-cache enabled on
    Enable the index cache.
    When on, enable the use of the index cache.

After:

    (gdb) help set index-cache enabled
    Enable the index cache.
    When on, enable the use of the index cache.
    (gdb) help set index-cache on
    Warning: 'set index-cache on', an alias for the command 'set index-cache enabled', is deprecated.
    Use 'set index-cache enabled on'.

    Enable the index cache.
    When on, enable the use of the index cache.

Change-Id: I989b618a5ad96ba975367e9d16db95523cd57a4c
2021-12-04 09:06:23 -05:00
Simon Marchi
eccd14b3f5 gdb: change some alias functions parameters to const-reference
Now that we use intrusive list to link aliases, it becomes easier to
pass cmd_list_element arguments by const-reference rather than by
pointer to some functions, change a few.

Change-Id: Id0df648ed26e9447da0671fc2c858981cda31df8
2021-12-03 16:48:42 -05:00
Simon Marchi
c471bdb198 gdb: use intrusive_list for cmd_list_element aliases list
Change the manually-implemented linked list to use intrusive_list.  This
is not strictly necessary, but it makes the code much simpler.

Change-Id: Idd08090ebf2db8bdcf68e85ef72a9635f1584ccc
2021-12-03 16:48:23 -05:00
Simon Marchi
ce1a6f421d gdb: make saved_filename an std::string
Make this variable an std::string, avoiding manual memory management.

Change-Id: Ie7a8d7381449ab9c4dfc4cb8b99e63b9ffa8f947
2021-12-03 08:24:11 -05:00
Andrew Burgess
43077a2374 gdb: rename source_styling_changed observer
In a later commit I plan to add disassembler styling.  In the same way
that we have a source_styling_changed observer I would need to add a
disassembler_styling_changed observer.

However, currently, these observers would only be notified from
cli-style.c:set_style_enabled, and observed in tui-winsource.c,
tui_source_window::style_changed, as a result, having two observers
seems unnecessary right now, so, in this commit, I plan to rename
source_styling_changed to just styling_changed, then, in the later
commit, when disassembler styling is added, I can use the same
observer for both source styling, and disassembler styling.

There should be no user visible changes after this commit.
2021-11-25 10:14:50 +00:00
Tom de Vries
6ff9675421 [gdb/cli] Add "set logging enabled", deprecate "set logging on/off"
Before commit 3b6acaee89 "Update more calls to add_prefix_cmd" we had the
following output for "show logging file":
...
$ gdb -q -batch -ex "set trace-commands on" \
    -ex "set logging off" \
    -ex "show logging file" \
    -ex "set logging on" \
    -ex "show logging file"
+set logging off
+show logging file
Future logs will be written to gdb.txt.
+set logging on
+show logging file
Currently logging to "gdb.txt".
...

After that commit we have instead:
...
+set logging off
+show logging file
The current logfile is "gdb.txt".
+set logging on
+show logging file
The current logfile is "gdb.txt".
...

Before the commit, whether logging is enabled or not can be deduced from the
output of the command.  After the commit, the message is unified and it's no
longer clear whether logging is enabled or not.

Fix this by:
- adding a new command "show logging enabled"
- adding a corresponding new command "set logging enabled on/off"
- making the commands "set logging on/off" deprecated aliases of the
  "set logging enabled on/off" command.

Update the docs and testsuite to use "set logging enabled".  Mention the new
and deprecated commands in NEWS.

Tested on x86_64-linux.
2021-11-25 07:49:16 +01:00
Tom de Vries
0a4a1c6a3b [gdb/cli] Fix typo in logging overwrite help text
Currently we have:
...
$ gdb -q -batch -ex "help set logging overwrite"
Set whether logging overwrites or appends to the log file.
If set, logging overrides the log file.
...

Fix overrides -> overwrites typo.
2021-11-25 07:49:16 +01:00
Simon Marchi
557b4d7650 gdbsupport: make gdb_assert_not_reached accept a format string
Change gdb_assert_not_reached to accept a format string plus
corresponding arguments.  This allows giving more precise messages.

Because the format string passed by the caller is prepended with a "%s:"
to add the function name, the callers can no longer pass a translated
string (`_(...)`).  Make the gdb_assert_not_reached include the _(),
just like the gdb_assert_fail macro just above.

Change-Id: Id0cfda5a57979df6cdaacaba0d55dd91ae9efee7
2021-11-18 11:29:19 -05:00
Andrew Burgess
8579fd136a gdb/gdbsupport: make xstrprintf and xstrvprintf return a unique_ptr
The motivation is to reduce the number of places where unmanaged
pointers are returned from allocation type routines.  All of the
callers are updated.

There should be no user visible changes after this commit.
2021-11-16 17:45:45 +00:00
Lancelot SIX
cc81bc2dfb [PR gdb/16238] Add completer for the show user command
The 'show user' command (which shows the definition of non-python/scheme
user defined commands) is currently missing a completer. This is
mentioned in PR 16238.  Having one can improve the user experience.

In this commit I propose an implementation for such completer as well as
the associated tests.

Tested on x86_64 GNU/Linux.

All feedbacks are welcome.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=16238
2021-11-14 13:50:30 +00:00
Simon Marchi
313f3b21cb gdb: remove bpstat typedef, rename bpstats to bpstat
I don't find that the bpstat typedef, which hides a pointer, is
particularly useful.  In fact, it confused me many times, and I just see
it as something to remember that adds cognitive load.  Also, with C++,
we might want to be able to pass bpstats objects by const-reference, not
necessarily by pointer.

So, remove the bpstat typedef and rename struct bpstats to bpstat (since
it represents one bpstat, it makes sense that it is singular).

Change-Id: I52e763b6e54ee666a9e045785f686d37b4f5f849
2021-11-08 16:39:14 -05:00
Tom Tromey
be77dd73c7 Introduce make_unique_xstrndup
This adds a new make_unique_xstrndup function, which is the "n"
analogue of make_unique_xstrdup.  It also updates a couple existing
places to use this function.
2021-11-05 13:58:48 -06:00
Simon Marchi
fcef6471ed gdb: pass/return setting setter/getter scalar values by value
The getter and setter in struct setting always receive and return values
by const reference.  This is not necessary for scalar values (like bool
and int), but more importantly it makes it a bit annoying to write a
getter, you have to use a scratch static variable or something similar
that you can refer to:

  const bool &
  my_getter ()
  {
    static bool value;
    value = function_returning_bool ();
    return value;
  }

Change the getter and setter function signatures to receive and return
value by value instead of by reference, when the underlying data type is
scalar.  This means that string-based settings will still use
references, but all others will be by value.  The getter above would
then be re-written as:

  bool
  my_getter ()
  {
    return function_returning_bool ();
  }

This is useful for a patch later in this series that defines a boolean
setting with a getter and a setter.

Change-Id: Ieca3a2419fcdb75a6f75948b2c920b548a0af0fd
2021-11-04 15:48:57 -04:00
Simon Marchi
7ead06a8b6 gdb: remove command_class enum class_deprecated
The class_deprecated enumerator isn't assigned anywhere, so remove it.
Commands that are deprecated have cmd_list_element::cmd_deprecated set
instead.

Change-Id: Ib35e540915c52aa65f13bfe9b8e4e22e6007903c
2021-11-04 15:40:52 -04:00
Simon Marchi
143f5a3837 gdb: remove unnecessary cmd_list_element::aliases nullptr checks
Remove two unnecessary nullptr checks.  If aliases is nullptr, then the
for loops will simply be skipped.

Change-Id: I9132063bb17798391f8d019af305383fa8e0229f
2021-11-04 15:40:44 -04:00
Simon Marchi
f54bdb6d27 gdb: add add_setshow_prefix_cmd
There's a common pattern to call add_basic_prefix_cmd and
add_show_prefix_cmd to add matching set and show commands.  Add the
add_setshow_prefix_cmd function to factor that out and use it at a few
places.

Change-Id: I6e9e90a30e9efb7b255bf839cac27b85d7069cfd
2021-10-28 10:44:18 -04:00
Simon Marchi
50888e42dc gdb: change functions returning value contents to use gdb::array_view
The bug fixed by this [1] patch was caused by an out-of-bounds access to
a value's content.  The code gets the value's content (just a pointer)
and then indexes it with a non-sensical index.

This made me think of changing functions that return value contents to
return array_views instead of a plain pointer.  This has the advantage
that when GDB is built with _GLIBCXX_DEBUG, accesses to the array_view
are checked, making bugs more apparent / easier to find.

This patch changes the return types of these functions, and updates
callers to call .data() on the result, meaning it's not changing
anything in practice.  Additional work will be needed (which can be done
little by little) to make callers propagate the use of array_view and
reap the benefits.

[1] https://sourceware.org/pipermail/gdb-patches/2021-September/182306.html

Change-Id: I5151f888f169e1c36abe2cbc57620110673816f3
2021-10-25 14:51:44 -04:00
Lancelot SIX
1a98bb552d gdb: Setting setter return a bool to tell if the value changed
GDB can notify observers when a parameter is changed.

To do that, do_set_command (in gdb/cli/cli-setshow.c) compares the new
value against the old one before updating it, and based on that notifies
observers.  This looks like something like:

    int valuechanged = 0;
    switch (cmd->var.type ())
    {
    case var_integer:
      {
        LONGEST new_val = parse_and_eval_long (arg)
        if (new_val != cmd->var.get<int> ())
        {
          cmd->var.get<int> (new_val);
          value_changes = 1;
        }
      }
    case var_uinteger:
    case var_zuinteger:
      {
        unsigned int val
          = parse_cli_var_uinteger (c->var->type (), &arg, true);
        if (c->var->get<unsigned int> () != val)
          {
            c->var->set<unsigned int> (val);
            option_changed = true;
          }
      }
    case...
      /* And so on for all possible var_types.  */
    }

This comparison is done for each possible var_type, which leads to
unnecessary logic duplication.

In this patch I propose to move all those checks in one place within the
setting setter method.  This limits the code duplication and simplifies
the do_set_command implementation.

This patch also changes slightly the way a value change is detected.
Instead of comparing the user provided value against the current value
of the setting, we compare the value of the setting before and after the
set operation.  This is meant to handle edge cases where trying to set
an unrecognized value would be equivalent to a noop (the actual value
remains unchanged).  Doing this requires that the original value needs
to be copied before the update, which can be non trivial for
std::string.

There should be no user visible change introduced by this commit.

Tested on x86_64 GNU/Linux.

[1] https://review.lttng.org/c/binutils-gdb/+/5831/41

Change-Id: If064b9cede3eb56275aacd2b286f74eceb1aed11
2021-10-03 17:53:16 +01:00
Lancelot SIX
702991711a gdb: Have setter and getter callbacks for settings
The main motivation behind this improvement is to help the
implementation of a patch Simon Marchi is preparing to fix a bug when
MI or Python try to access parameters that are inferior dependent (see
PR/28085).

This commit extends the previous ones, which introduces the setting
object to represent a static variable whose value can be set or shown
with the appropriate commands.  This patch proposes that a setting can
either contain a pointer to a static variable holding a setting, or
pointers to a pair of setter and getter callback functions.

The callbacks functions can be used to retrieve or change the value with
custom logic.  This is useful when the source of truth for a given
setting is not contained in the variable pointed to by the setting
instance.

Given that the callback function call is hidden within the setting
abstraction introduced earlier, none of the sites accessing the setting
needs to be updated.  The registered getter or setter is used whatever
the way to access it is (through MI, Python, Guile, the "with" command
and the $_gdb_setting / $_gdb_setting_str convenience functions).

All the add_setshow_*_cmd are given a new overload that will accept the
pair of function pointers (set / get functions) instead of the pointer
to a global variable.

Tested on GNU/Linux x86_64 with no regression observed.

Change-Id: Ieb81fef57550632ff66e6aa85f637372a226be8c
Co-authored-by: Simon Marchi <simon.marchi@polymtl.ca>
2021-10-03 17:53:16 +01:00
Simon Marchi
e0700ba44c gdb: make string-like set show commands use std::string variable
String-like settings (var_string, var_filename, var_optional_filename,
var_string_noescape) currently take a pointer to a `char *` storage
variable (typically global) that holds the setting's value.  I'd like to
"mordernize" this by changing them to use an std::string for storage.

An obvious reason is that string operations on std::string are often
easier to write than with C strings.  And they avoid having to do any
manual memory management.

Another interesting reason is that, with `char *`, nullptr and an empty
string often both have the same meaning of "no value".  String settings
are initially nullptr (unless initialized otherwise).  But when doing
"set foo" (where `foo` is a string setting), the setting now points to
an empty string.  For example, solib_search_path is nullptr at startup,
but points to an empty string after doing "set solib-search-path".  This
leads to some code that needs to check for both to check for "no value".
Or some code that converts back and forth between NULL and "" when
getting or setting the value.  I find this very error-prone, because it
is very easy to forget one or the other.  With std::string, we at least
know that the variable is not "NULL".  There is only one way of
representing an empty string setting, that is with an empty string.

I was wondering whether the distinction between NULL and "" would be
important for some setting, but it doesn't seem so.  If that ever
happens, it would be more C++-y and self-descriptive to use
optional<string> anyway.

Actually, there's one spot where this distinction mattered, it's in
init_history, for the test gdb.base/gdbinit-history.exp.  init_history
sets the history filename to the default ".gdb_history" if it sees that
the setting was never set - if history_filename is nullptr.  If
history_filename is an empty string, it means the setting was explicitly
cleared, so it leaves it as-is.  With the change to std::string, this
distinction doesn't exist anymore.  This can be fixed by moving the code
that chooses a good default value for history_filename to
_initialize_top.  This is ran before -ex commands are processed, so an
-ex command can then clear that value if needed (what
gdb.base/gdbinit-history.exp tests).

Another small improvement, in my opinion is that we can now easily
give string parameters initial values, by simply initializing the global
variables, instead of xstrdup-ing it in the _initialize function.

In Python and Guile, when registering a string-like parameter, we
allocate (with new) an std::string that is owned by the param_smob (in
Guile) and the parmpy_object (in Python) objects.

This patch started by changing all relevant add_setshow_* commands to
take an `std::string *` instead of a `char **` and fixing everything
that failed to build.  That includes of course all string setting
variable and their uses.

string_option_def now uses an std::string also, because there's a
connection between options and settings (see
add_setshow_cmds_for_options).

The add_path function in source.c is really complex and twisted, I'd
rather not try to change it to work on an std::string right now.
Instead, I added an overload that copies the std:string to a `char *`
and back.  This means more copying, but this is not used in a hot path
at all, so I think it is acceptable.

Change-Id: I92c50a1bdd8307141cdbacb388248e4e4fc08c93
Co-authored-by: Lancelot SIX <lsix@lancelotsix.com>
2021-10-03 17:53:16 +01:00