247 Commits

Author SHA1 Message Date
7aeb03e2d4 GDB: Allow arbitrary keywords in integer set commands
Rather than just `unlimited' allow the integer set commands (or command
options) to define arbitrary keywords for the user to use, removing
hardcoded arrangements for the `unlimited' keyword.

Remove the confusingly named `var_zinteger', `var_zuinteger' and
`var_zuinteger_unlimited' `set'/`show' command variable types redefining
them in terms of `var_uinteger', `var_integer' and `var_pinteger', which
have the range of [0;UINT_MAX], [INT_MIN;INT_MAX], and [0;INT_MAX] each.

Following existing practice `var_pinteger' allows extra negative values
to be used, however unlike `var_zuinteger_unlimited' any number of such
values can be defined rather than just `-1'.

The "p" in `var_pinteger' stands for "positive", for the lack of a more
appropriate unambiguous letter, even though 0 obviously is not positive;
"n" would be confusing as to whether it stands for "non-negative" or
"negative".

Add a new structure, `literal_def', the entries of which define extra
keywords allowed for a command and numerical values they correspond to.
Those values are not verified against the basic range supported by the
underlying variable type, allowing extra values to be allowed outside
that range, which may or may not be individually made visible to the
user.  An optional value translation is possible with the structure to
follow the existing practice for some commands where user-entered 0 is
internally translated to UINT_MAX or INT_MAX.  Such translation can now
be arbitrary.  Literals defined by this structure are automatically used
for completion as necessary.

So for example:

const literal_def integer_unlimited_literals[] =
  {
    { "unlimited", INT_MAX, 0 },
    { nullptr }
  };

defines an extra `unlimited' keyword and a user-visible 0 value, both of
which get translated to INT_MAX for the setting to be used with.

Similarly:

const literal_def zuinteger_unlimited_literals[] =
  {
    { "unlimited", -1, -1 },
    { nullptr }
  };

defines the same keyword and a corresponding user-visible -1 value that
is used for the requested setting.  If the last member were omitted (or
set to `{}') here, then only the keyword would be allowed for the user
to enter and while -1 would still be used internally trying to enter it
as a part of a command would result in an "integer -1 out of range"
error.

Use said error message in all cases (citing the invalid value requested)
replacing "only -1 is allowed to set as unlimited" previously used for
`var_zuinteger_unlimited' settings only rather than propagating it to
`var_pinteger' type.  It could only be used for the specific case where
a single extra `unlimited' keyword was defined standing for -1 and the
use of numeric equivalents is discouraged anyway as it is for historical
reasons only that they expose GDB internals, confusingly different
across variable types.  Similarly update the "must be >= -1" Guile error
message.

Redefine Guile and Python parameter types in terms of the new variable
types and interpret extra keywords as Scheme keywords and Python strings
used to communicate corresponding parameter values.  Do not add a new
PARAM_INTEGER Guile parameter type, however do handle the `var_integer'
variable type now, permitting existing parameters defined by GDB proper,
such as `listsize', to be accessed from Scheme code.

With these changes in place it should be trivial for a Scheme or Python
programmer to expand the syntax of the `make-parameter' command and the
`gdb.Parameter' class initializer to have arbitrary extra literals along
with their internal representation supplied.

Update the testsuite accordingly.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-01-19 21:15:56 +00:00
0e38c6ff4f GDB: Add references to erased args in cli-decode.c
Complement commit 1d7fe7f01b93 ("gdb: Introduce setting construct within
cmd_list_element") and commit 702991711a91 ("gdb: Have setter and getter
callbacks for settings") and update inline documentation accordingly for
`add_set_or_show_cmd' and `add_setshow_cmd_full_erased', documenting the
`args' parameter and removing references to `var', `set_setting_func'
and `get_setting_func'.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-01-18 23:38:50 +00:00
439ee79344 GDB: Add missing inline documentation for `add_setshow_cmd_full'
Complement commit 1d7fe7f01b93 ("gdb: Introduce setting construct
within cmd_list_element") and add missing description for
`add_setshow_cmd_full'.
2023-01-18 23:23:00 +00:00
3cfe8022bd GDB: Correct inline documentation for `add_setshow_cmd_full_erased'
Use proper English in the description of SET_LIST and SHOW_LIST.
2023-01-18 23:23:00 +00:00
a58c879377 GDB: Fix documentation for `theclass' parameters in cli-decode.c
Rename CLASS to THECLASS in the documentation for `theclass' parameters
throughout cli-decode.c, complementing commit fe978cb071b4 ("C++ keyword
cleanliness, mostly auto-generated").

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-01-18 21:54:37 +00:00
213516ef31 Update copyright year range in header of all files managed by GDB
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
2023-01-01 17:01:16 +04:00
effcf7b144 Allow to document user-defined aliases.
Compared to the previous version, this version fixes the comments reported by
Tom Tromey and ensures that the 'help some-user-documented-alias'
shows the alias definition to ensure the user understands this is an
alias even if specifically documented.

When using 'help ALIASNAME', GDB shows the help of the aliased command.
This is a good default behaviour.

However, GDB alias command allows to define aliases with arguments
possibly changing or tuning significantly the behaviour of
the aliased command.  In such a case, showing the help of the aliased
command might not be ideal.

This is particularly true when defining an alias as a set of
nested 'with' followed by a last command to launch, such as:
  (gdb) alias pp10 = with print pretty -- with print elements 10 -- print
Asking 'help pp10' shows the help of the 'with' command, which is
not particularly useful:
  (gdb) help pp10
  with, pp10, w
    alias pp10 = with print pretty -- with print elements 10 -- print
  Temporarily set SETTING to VALUE, run COMMAND, and restore SETTING.
  Usage: with SETTING [VALUE] [-- COMMAND]
  ....

Such an alias can now be documented by the user:
  (gdb) document pp10
  >Pretty printing an expressiong, printing 10 elements.
  >Usage: pp10 [PRINT-COMMAND-OPTIONS] EXP
  >See 'help print' for more information.
  >end
  (gdb) help pp10
    alias pp10 = with print pretty -- with print elements 10 -- print
  Pretty printing an expressiong, printing 10 elements.
  Usage: pp10 [PRINT-COMMAND-OPTIONS] EXP
  See 'help print' for more information.
  (gdb)

When a user-defined alias is documented specifically, help and apropos
use the provided alias documentation instead of the documentation of
the aliased command.

Such a documented alias is also not shown anymore in the help of the
aliased command, and the alias is not listed anymore in the help
of the aliased command.  In particular for cases such as pp10 example above,
indicating that pp10 is an alias of the 'with' command is confusing.
2022-08-25 18:57:25 +02:00
89555e4ec2 GDB: Add NUMBER' completion to set' integer commands
Fix a completion consistency issue with `set' commands accepting integer
values and the special `unlimited' keyword:

(gdb) complete print -elements
print -elements NUMBER
print -elements unlimited
(gdb)

vs:

(gdb) complete set print elements
set print elements unlimited
(gdb)

(there is a space entered at the end of both commands, not shown here)
which also means if you strike <Tab> with `set print elements ' input,
it will, annoyingly, complete to `set print elements unlimited' right
away rather than showing a choice between `NUMBER' and `unlimited'.

Add `NUMBER' then as an available completion for such `set' commands:

(gdb) complete set print elements
set print elements NUMBER
set print elements unlimited
(gdb)

Adjust the testsuite accordingly.  Also document the feature in the
Completion section of the manual in addition to the Command Options
section already there.
2022-06-30 19:57:34 +01:00
6cb06a8cda Unify gdb printf functions
Now that filtered and unfiltered output can be treated identically, we
can unify the printf family of functions.  This is done under the name
"gdb_printf".  Most of this patch was written by script.
2022-03-29 12:46:24 -06:00
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
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
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
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
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
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
d322d6d69d Move gdb_regex to gdbsupport
This moves the gdb_regex convenience class to gdbsupport.
2022-01-18 10:14:43 -07:00
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
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
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
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
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
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
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
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
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
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
1d7fe7f01b gdb: Introduce setting construct within cmd_list_element
cmd_list_element can contain a pointer to data that can be set and / or
shown.  This is achieved with the void* VAR member which points to the
data that can be accessed, while the VAR_TYPE member (of type enum
var_types) indicates how to interpret the data pointed to.

With this pattern, the user of the cmd_list_element needs to know what
is the storage type associated with a given VAR_TYPES in order to do
the proper casting.  No automatic safeguard is available to prevent
miss-use of the pointer.  Client code typically looks something like:

	switch (c->var_type)
	{
	  case var_zuinteger:
	    unsigned int v = *(unsigned int*) c->var;
	    ...
	    break;
	  case var_boolean:
	    bool v = *(bool *) c->var;
	    ...
	    break;
	  ...
	}

This patch proposes to add an abstraction around the var_types and void*
pointer pair.  The abstraction is meant to prevent the user from having
to handle the cast and verify that the data is read or written as a type
that is coherent with the setting's var_type.  This is achieved by
introducing the struct setting which exposes a set of templated get /
set member functions.  The template parameter is the type of the
variable that holds the referred variable.

Using those accessors allows runtime checks to be inserted in order to
ensure that the data pointed to has the expected type.  For example,
instantiating the member functions with bool will yield something
similar to:

	const bool &get<bool> () const
	{
	  gdb_assert (m_var_type == var_boolean);
	  gdb_assert (m_var != nullptr);
	  return *static_cast<bool *> (m_var);
	}
	void set<bool> (const bool &var)
	{
	  gdb_assert (m_var_type == var_boolean);
	  gdb_assert (m_var != nullptr);
	  *static_cast<bool *> (m_var) = var;
	}

Using the new abstraction, our initial example becomes:

	switch (c->var_type)
	{
	  case var_zuinteger:
	    unsigned int v = c->var->get<unsigned int> ();
	    ...
	    break;
	  case var_boolean:
	    bool v = c->var->get<bool> ();
	    ...
	    break;
	  ...
	}

While the call site is still similar, the introduction of runtime checks
help ensure correct usage of the data.

In order to avoid turning the bulk of add_setshow_cmd_full into a
templated function, and following a suggestion from Pedro Alves, a
setting can be constructed from a pre validated type erased reference to
a variable.  This is what setting::erased_args is used for.

Introducing an opaque abstraction to describe a setting will also make
it possible to use callbacks to retrieve or set the value of the setting
on the fly instead of pointing to a static chunk of memory.  This will
be done added in a later commit.

Given that a cmd_list_element may or may not reference a setting, the
VAR and VAR_TYPES members of the struct are replaced with a
gdb::optional<setting> named VAR.

Few internal function signatures have been modified to take into account
this new abstraction:

-The functions value_from_setting, str_value_from_setting and
 get_setshow_command_value_string used to have a 'cmd_list_element *'
 parameter but only used it for the VAR and VAR_TYPE member. They now
 take a 'const setting &' parameter instead.
- Similarly, the 'void *' and a 'enum var_types' parameters of
  pascm_param_value and gdbpy_parameter_value have been replaced with a
  'const setting &' parameter.

No user visible change is expected after this patch.

Tested on GNU/Linux x86_64, with no regression noticed.

Co-authored-by: Simon Marchi <simon.marchi@polymtl.ca>
Change-Id: Ie1d08c3ceb8b30b3d7bf1efe036eb8acffcd2f34
2021-10-03 17:53:16 +01:00
5538b03c98 gdb: remove cmd_list_element::function::sfunc
I don't understand what the sfunc function type in
cmd_list_element::function is for.  Compared to cmd_simple_func_ftype,
it has an extra cmd_list_element parameter, giving the callback access
to the cmd_list_element for the command being invoked.  This allows
registering the same callback with many commands, and alter the behavior
using the cmd_list_element's context.

From the comment in cmd_list_element, it sounds like at some point it
was the callback function type for set and show functions, hence the
"s".  But nowadays, it's used for many more commands that need to access
the cmd_list_element object (see add_catch_command for example).

I don't really see the point of having sfunc at all, since do_sfunc is
just a trivial shim that changes the order of the arguments.  All
commands using sfunc could just as well set cmd_list_element::func to
their callback directly.

Therefore, remove the sfunc field in cmd_list_element and everything
that goes with it.  Rename cmd_const_sfunc_ftype to cmd_func_ftype and
use it for cmd_list_element::func, as well as for the add_setshow
commands.

Change-Id: I1eb96326c9b511c293c76996cea0ebc51c70fac0
2021-07-23 15:38:54 -04:00
3a553c80da gdb: rename cfunc to simple_func
After browsing the CLI code for quite a while and trying really hard, I
reached the conclusion that I can't give a meaningful explanation of
what "sfunc" and "cfunc" functions are, in cmd_list_element.  I don't
see a logic at all.  That makes it very difficult to do any kind of
change.  Unless somebody can make sense out of all that, I'd like to try
to retro-fit some logic in the cmd_list_element callback function code
so that we can understand what is going on, do some cleanups and add new
features.

The first change is about "cfunc".  I can't figure out what the "c" in
cfunc means.  It's not const, because there's already "const" in
"cmd_const_cfunc_ftype", and the previous "cmd_cfunc_ftype" had nothing
const..  It's not "cmd" or "command", because there's already "cmd" in
"cmd_const_cfunc_ftype".

The "main" command callback, cmd_list_element::func, has three
parameters, whereas cfunc has two.  It is missing the cmd_list_element
parameter.  So the only reason I see for cfunc to exist is to be a shim
between the three and two parameter versions.  Most commands don't need
to receive the cmd_list_element object, so adding it everywhere would be
long and would just add more unnecessary boilerplate.  So since this is
the "simple" version of the callback, compared to the "full", I suggest
renaming cmd_const_cfunc_ftype into cmd_simple_func_ftype, as well as
everything (like the utility functions) that goes with it.

Change-Id: I4e46cacfd77a66bc1cbf683f6a362072504b7868
2021-07-23 15:38:54 -04:00
4c0ba02a74 gdb: remove context parameter from add_setshow_enum_cmd
I propose removing the context parameter from add_setshow_enum_cmd.  It
was useful before add_setshow_enum_cmd returned both created commands,
as the caller couldn't easily set the context itself.  But now, I think
it's fine to just let the caller do it.

gdb/ChangeLog:

	* command.h (add_setshow_enum_cmd): Remove context parameter.
	* cli/cli-decode.c (add_setshow_enum_cmd): Likewise, and don't
	set context.
	* cli/cli-style.c (cli_style_option::add_setshow_commands): Set
	context here.

Change-Id: I377c4e6820ec9d5069492ed28f4cba342ce1336e
2021-06-25 21:39:26 -04:00
0f8e203412 gdb: add context getter/setter to cmd_list_element
Straightforward replacement of get_cmd_context / set_cmd_context with
cmd_list_element methods.

gdb/ChangeLog:

	* cli/cli-decode.h (struct cmd_list_element) <set_context,
	context>: New.
	<context>: Rename to...
	<m_context>: ... this.
	* cli/cli-decode.c (set_cmd_context, get_cmd_context): Remove.
	* command.h (set_cmd_context, get_cmd_context): Remove, use
	cmd_list_element::set_context and cmd_list_element::context
	everywhere instead.

Change-Id: I5016b0079014e3f17d1aa449ada7954473bf2b5d
2021-06-25 21:35:40 -04:00
5e84b7eefb gdb: remove add_alias_cmd overload that accepts a string
Same idea as previous patch, but for add_alias_cmd.  Remove the overload
that accepts the target command as a string (the target command name),
leaving only the one that takes the cmd_list_element.

gdb/ChangeLog:

	* command.h (add_alias_cmd): Accept target as
	cmd_list_element.  Update callers.

Change-Id: I546311f411e9e7da9302322d6ffad4e6c56df266
2021-05-27 14:00:08 -04:00
e0f25bd971 gdb: make add_info_alias accept target as a cmd_list_element
Same idea as previous patch, but for add_info_alias.

gdb/ChangeLog:

	* command.h (add_info_alias): Accept target as
	cmd_list_element.  Update callers.

Change-Id: If830d423364bf42d7bea5ac4dd3a81adcfce6f7a
2021-05-27 14:00:07 -04:00
3947f654ea gdb: make add_com_alias accept target as a cmd_list_element
The alias creation functions currently accept a name to specify the
target command.  They pass this to add_alias_cmd, which needs to lookup
the target command by name.

Given that:

 - We don't support creating an alias for a command before that command
   exists.
 - We always use add_info_alias just after creating that target command,
   and therefore have access to the target command's cmd_list_element.

... change add_com_alias to accept the target command as a
cmd_list_element (other functions are done in subsequent patches).  This
ensures we don't create the alias before the target command, because you
need to get the cmd_list_element from somewhere when you call the alias
creation function.  And it avoids an unecessary command lookup.  So it
seems better to me in every aspect.

gdb/ChangeLog:

	* command.h (add_com_alias): Accept target as
	cmd_list_element.  Update callers.

Change-Id: I24bed7da57221cc77606034de3023fedac015150
2021-05-27 14:00:07 -04:00
af7f8f52dd gdb: make add_setshow commands return set_show_commands
Some add_set_show commands return a single cmd_list_element, the one for
the "set" command.  A subsequent patch will need to access the show
command's cmd_list_element as well.  Change these functions to return a
new structure type that holds both pointers.

I initially only modified add_setshow_boolean_cmd (the one I needed),
but I think it's better to change the whole chain to keep everything in
sync.

gdb/ChangeLog:

	* command.h (set_show_commands): New.
	(add_setshow_enum_cmd, add_setshow_auto_boolean_cmd,
	add_setshow_boolean_cmd, add_setshow_filename_cmd,
	add_setshow_string_cmd, add_setshow_string_noescape_cmd,
	add_setshow_optional_filename_cmd, add_setshow_integer_cmd,
	add_setshow_uinteger_cmd, add_setshow_zinteger_cmd,
	add_setshow_zuinteger_cmd, add_setshow_zuinteger_unlimited_cmd):
	Return set_show_commands.  Adjust callers.
	* cli/cli-decode.c (add_setshow_cmd_full): Return
	set_show_commands, remove result parameters, adjust callers.

Change-Id: I17492b01b76002d09effc84830f9c6db26f1db7a
2021-05-27 14:00:07 -04:00
034dce7a47 gdb: add cmd_list_element::is_command_class_help
Same idea as the previous patches, but for whether a command is a
"command class help" command.  I think this one is particularly useful,
because it's not obvious when reading code what "c->func == NULL" means.

Remove the cmd_func_p function, which does kind of the same thing as
cmd_list_element::is_command_class_help (except it doesn't give a clue
about the semantic of a NULL func value).

gdb/ChangeLog:

	* cli/cli-decode.h (cmd_list_element) <is_command_class_help>:
	New, use it.
	* command.h (cmd_func_p): Remove.
	* cli/cli-decode.c (cmd_func_p): Remove.

Change-Id: I521a3e1896dc93a5babe1493d18f5eb071e1b3b7
2021-05-17 14:01:32 -04:00
3d0b356410 gdb: add cmd_list_element::is_prefix
Same idea as the previous patch, but for prefix instead of alias.

gdb/ChangeLog:

	* cli/cli-decode.h (cmd_list_element) <is_prefix>: New, use it.

Change-Id: I76a9d2e82fc8d7429904424674d99ce6f9880e2b
2021-05-17 14:01:26 -04:00
1be99b11f8 gdb: add cmd_list_element::is_alias
Add the cmd_list_element::is_alias helper to check whether a command is
an alias.  I find it easier to understand the intention in:

  if (c->is_alias ())

than

  if (c->alias_target != nullptr)

Change all the spots that are reading alias_target just to compare it to
NULL/nullptr to use is_alias instead.

gdb/ChangeLog:

	* cli/cli-decode.h (cmd_list_element) <is_alias>: New, use it.

Change-Id: I26ed56f99ee47fe884fdfedf87016501631693ce
2021-05-17 14:01:20 -04:00
9985872497 gdb: rename cmd_list_element::cmd_pointer to target
cmd_pointer is another field whose name I found really not clear.  Yes,
it's a pointer to a command, the type tells me that.  But what's the
relationship of that command to the current command?  This field
contains, for an alias, the command that it aliases.  So I think that
the name "alias_target" would be more appropriate.

Also, rename "old" parameters to "target" in the functions that add
aliases.

gdb/ChangeLog:

	* cli/cli-decode.h (cmd_list_element) <cmd_pointer>: Rename
	to...
	<alias_target>: ... this.
	(add_alias_cmd): Rename old to target.
	(add_info_alias): Rename old_name to target_name.
	(add_com_alias): Likewise.

Change-Id: I8db36c6dd799fae155f7acd3805f6d62d98befa9
2021-05-17 14:01:14 -04:00
14b42fc4a0 gdb: rename cmd_list_element::prefixlist to subcommands
While browsing this code, I found the name "prefixlist" really
confusing.  I kept reading it as "list of prefixes".  Which it isn't:
it's a list of sub-commands, for a prefix command.  I think that
renaming it to "subcommands" would make things clearer.

gdb/ChangeLog:

	* Rename "prefixlist" parameters to "subcommands" throughout.
	* cli/cli-decode.h (cmd_list_element) <prefixlist>: Rename to...
	<subcommands>: ... this.
	* cli/cli-decode.c (lookup_cmd_for_prefixlist): Rename to...
	(lookup_cmd_with_subcommands): ... this.

Change-Id: I150da10d03052c2420aa5b0dee41f422e2a97928
2021-05-17 14:01:08 -04:00
ecd0a6b35d gdb: don't handle old == nullptr in add_alias_cmd
I don't think this can ever happen, that we add an alias command and
pass a nullptr old (target) command.  Remove the "if" handling this,
replace with an assert.

gdb/ChangeLog:

	* cli/cli-decode.c (add_alias_cmd): Don't handle old == 0.

Change-Id: Ibb39e8dc4e0c465fa42e6826215f30a0a0aef932
2021-05-17 14:01:01 -04:00
413b49c2b6 gdb: move cmd_list_element::prefixname to cli/cli-decode.c
I don't think this method really benefits from being implemented in the
header file, especially because it's recursive, it can't be inlined.
Move it to the source file, so it's no re-compiled by every CU
including cli/cli-decode.h.

I also noticed this method could be const, make it so.

gdb/ChangeLog:

	* cli/cli-decode.h (prefixname): Make const, move implementation
	to cli/cli-decode.c.
	* cli/cli-decode.c (cmd_list_element::prefixname): New.

Change-Id: I1597cace98d9a4ba71f51f1f495e73cc07b5dcf3
2021-05-17 14:00:48 -04:00
2f822da535 gdb: generate the prefix name for prefix commands on demand
Previously, the prefixname field of struct cmd_list_element was manually
set for prefix commands.  This seems verbose and error prone as it
required every single call to functions adding prefix commands to
specify the prefix name while the same information can be easily
generated.

Historically, this was not possible as the prefix field was null for
many commands, but this was fixed in commit
3f4d92ebdf7f848b5ccc9e8d8e8514c64fde1183 by Philippe Waroquiers, so
we can rely on the prefix field being set when generating the prefix
name.

This commit also fixes a use after free in this scenario:
* A command gets created via Python (using the gdb.Command class).
  The prefix name member is dynamically allocated.
* An alias to the new command is created. The alias's prefixname is set
  to point to the prefixname for the original command with a direct
  assignment.
* A new command with the same name as the Python command is created.
* The object for the original Python command gets freed and its
  prefixname gets freed as well.
* The alias is updated to point to the new command, but its prefixname
  is not updated so it keeps pointing to the freed one.

gdb/ChangeLog:

	* command.h (add_prefix_cmd): Remove the prefixname argument as
	it can now be generated automatically.  Update all callers.
	(add_basic_prefix_cmd): Ditto.
	(add_show_prefix_cmd): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_abbrev_prefix_cmd): Ditto.
	* cli/cli-decode.c (add_prefix_cmd): Ditto.
	(add_basic_prefix_cmd): Ditto.
	(add_show_prefix_cmd): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_abbrev_prefix_cmd): Ditto.
	* cli/cli-decode.h (struct cmd_list_element): Replace the
	prefixname member variable with a method which generates the
	prefix name at runtime.  Update all code reading the prefix
	name to use the method, and remove all code setting it.
	* python/py-cmd.c (cmdpy_destroyer): Remove code to free the
	prefixname member as it's now a method.
	(cmdpy_function): Determine if the command is a prefix by
	looking at prefixlist, not prefixname.
2021-05-12 11:19:22 +01:00
a9b49cbcd5 gdb: add lookup_cmd_exact to simplify a common pattern
In code dealing with commands, there's a pattern repeated a few times of
calling lookup_cmd with some speficic arguments and then using strcmp
on the returned command to check for an exact match.
As a later patch would add a few more similar lines of code, this patch
adds a new lookup_cmd_exact function which simplify this use case.

gdb/ChangeLog:

	* cli/cli-decode.c (lookup_cmd_exact): Add.
	* cli/cli-script.c (do_define_command): Use lookup_cmd_exact.
	(define_prefix_command): Ditto.
	* command.h: Add lookup_cmd_exact.
2021-05-07 15:43:30 +01:00
3666a04883 Update copyright year range in all GDB files
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...

gdb/ChangeLog

        Update copyright year range in copyright header of all GDB files.
2021-01-01 12:12:21 +04:00
0e5ad4426a Highlight deprecated commands using title style
After Andrew's latest patch, I noticed that the deprecation warnings
could use the (so-called) title style when printing command names.
This patch implements this idea.

gdb/ChangeLog
2020-12-15  Tom Tromey  <tromey@adacore.com>

	* cli/cli-decode.c (deprecated_cmd_warning): Use title style for
	command names.

gdb/testsuite/ChangeLog
2020-12-15  Tom Tromey  <tromey@adacore.com>

	* gdb.base/style.exp: Add deprecation tests.
2020-12-15 08:07:32 -07:00
19c659f164 gdb: improve the warning given for deprecated aliases with a prefix
Consider this GDB session:

  (gdb) define set xxx_yyy
  Type commands for definition of "set xxx_yyy".
  End with a line saying just "end".
  >echo in set xxx_yyy command\n
  >end
  (gdb) alias set qqq_aaa=set xxx_yyy
  (gdb) maintenance deprecate set qqq_aaa
  (gdb) set qqq_aaa
  Warning: 'qqq_aaa', an alias for the command 'xxx_yyy' is deprecated.
  No alternative known.

  in set xxx_yyy command
  (gdb)

Notice the warning mentions 'qqq_aaa' and 'xxx_yyy', I consider this
to be wrong.  I think the proper warning should read:

  (gdb) set qqq_aaa
  Warning: 'set qqq_aaa', an alias for the command 'set xxx_yyy', is deprecated.
  No alternative known.

With the 'set' prefixes added and a comma before the final 'is
deprecated'.  That is what this patch does.  The expected results are
updated as needed.

gdb/ChangeLog:

	* cli/cli-decode.c (deprecated_cmd_warning): Ignore the prefix
	result from lookup_cmd_composition_1, use the prefixes from both
	the command and the alias instead.
	(lookup_cmd_composition_1): Initial prefix command is the based on
	the search list being passed in.  Simplify the logic for tracking
	the prefix command.  Replace a use of alloca with a local
	std::string.

gdb/testsuite/ChangeLog:

	* gdb.base/commands.exp: Update expected results.
2020-12-11 22:10:50 +00:00
44c77c3272 gdb: make deprecated_cmd_warning i18n friendly
Rewrite deprecated_cmd_warning to be i18n friendly.  While I'm going
through the function I also cleaned up some whitespace issues,
replaced uses of NULL with nullptr, and moved some comments to avoid
having to add { ... }.

Though the message being printed has a 'Warning: ' prefix I could have
changed from using printf_filtered to use warning, however, I haven't
done that in this commit as that would change what GDB outputs and I
wanted this commit NOT to change the output.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* cli/cli-decode.c (deprecated_cmd_warning): Use nullptr instead
	of NULL.  Don't print message piece by piece, but sentence at a
	time to allow internationalisation.  Some whitespace cleanup.
2020-12-11 22:10:50 +00:00
9ef6d4a1b4 gdb: give deprecated command warning for aliases with a prefix
I noticed that deprecated aliases that have a prefix don't give a
deprecated command warning.  For example looking in mi/mi-main.c we
see this:

  c = add_alias_cmd ("target-async", "mi-async", class_run, 0, &setlist);
  deprecate_cmd (c, "set mi-async");
  c = add_alias_cmd ("target-async", "mi-async", class_run, 0, &showlist);
  deprecate_cmd (c, "show mi-async");

So both 'set target-async' and 'show target-async' are deprecated and
should be giving a warning, however, in use we see no warning given.

This is a consequence of how the code that should give this
warning (deprecated_cmd_warning) performs a second command lookup in
order to distinguish between aliases and real commands, and that the
code that calls this (lookup_cmd_1) strips off prefix commands as it
calls itself recursively.

As a result when we are considering an alias like 'set target-async'
we first enter lookup_cmd_1 with text = "set target-async", we spot
the 'set' command prefix and then recursively call lookup_cmd_1 with
text = "target-async".

We spot that 'target-async' is a known alias but that it is
deprecated, and so call deprecated_cmd_warning passing in the value of
text, which remember is now "target-async".

In deprecated_cmd_warning we again perform a command lookup starting
from the top-level cmdlist, but now we're trying to find just
"target-async", this fails (as this command requires the 'set' prefix,
and so no warning is given.

I resolved this issue by passing a command list to the function
deprecated_cmd_warning, this is the list in which the command can be
found.

A new test is added to cover this case.

However, there is an additional problem which will be addressed in a
subsequent patch.

Consider this GDB session:

  (gdb) define set xxx_yyy
  Type commands for definition of "set xxx_yyy".
  End with a line saying just "end".
  >echo in set xxx_yyy command\n
  >end
  (gdb) alias set qqq_aaa=set xxx_yyy
  (gdb) maintenance deprecate set qqq_aaa
  (gdb) set qqq_aaa
  Warning: 'qqq_aaa', an alias for the command 'xxx_yyy' is deprecated.
  No alternative known.

  in set xxx_yyy command
  (gdb)

Notice the warning mentions 'qqq_aaa' and 'xxx_yyy', I consider this
to be wrong.  I think the proper warning should read:

  (gdb) set qqq_aaa
  Warning: 'set qqq_aaa', an alias for the command 'set xxx_yyy' is deprecated.
  No alternative known.

With the 'set' prefixes added.  A later patch will resolve this
issue.

gdb/ChangeLog:

	PR cli/15104
	* cli/cli-decode.c (lookup_cmd_1): Pass command list to
	deprecated_cmd_warning.
	(deprecated_cmd_warning): Take extra parameter, call
	lookup_cmd_composition_1 and pass new parameter through.
	(lookup_cmd_composition_1): New function, takes implementation of
	lookup_cmd_composition but with extra parameter.
	(lookup_cmd_composition): Now calls lookup_cmd_composition_1
	passing in cmdlist.
	* command.h (deprecated_cmd_warning): Add extra parameter to
	declaration.
	* top.c (execute_command): Pass cmdlist to deprecated_cmd_warning.

gdb/testsuite/ChangeLog:

	PR cli/15104
	* gdb.base/commands.exp: Add additional tests.
	* gdb.base/completion.exp: Add additional tests.
2020-12-11 22:10:50 +00:00
1536146f30 gdb: don't warn about deprecated aliases during tab completion
Consider this gdb session, where on line #3 tab completion is used:

  (gdb) alias xxx_yyy_zzz=break
  (gdb) maint deprecate xxx_yyy_zzz
  (gdb) xxx_yyy_<TAB>

The third line then updates to look like this:

  (gdb) xxx_yyy_Warning: 'xxx_yyy_zzz', an alias for the command 'break' is deprecated.
  No alternative known.

  zzz

What's happened is during tab completion the alias has been resolved
to the actual command being aliased, and at this stage the warning is
issued.  Clearly this is not what we want during tab completion.

In this commit I add a new parameter to the lookup function, a boolean
that indicates if the lookup is being done as part of completion.
This flag is used to suppress the warning.  Now we get the expected
behaviour, the alias completes without any warning, but the warning is
still given once the user executes the alias.

gdb/ChangeLog:

	* cli/cli-decode.c (lookup_cmd_1): Move header comment into
	command.h, add extra parameter, and use this to guard giving a
	warning.
	* command.h (lookup_cmd_1): Add comment from cli/cli-decode.c,
	include argument names in declaration, add new argument.
	* completer.c (complete_line_internal_1): Remove unneeded
	brackets, pass extra argument to lookup_cmd_1.

gdb/testsuite/ChangeLog:

	* gdb.base/completion.exp: Add additional tests.
2020-12-11 22:10:50 +00:00