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.
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.
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
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.)
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.
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.
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.
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
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
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.
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
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
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.
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.
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
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
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.
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.
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.
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.
"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.
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.
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
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
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
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
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.
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.
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.
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
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.
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
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
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.
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
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
Remove two unnecessary nullptr checks. If aliases is nullptr, then the
for loops will simply be skipped.
Change-Id: I9132063bb17798391f8d019af305383fa8e0229f
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
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
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
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>
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>