Teach gdb::option about string options
authorPedro Alves <palves@redhat.com>
Wed, 3 Jul 2019 15:57:49 +0000 (16:57 +0100)
committerPedro Alves <palves@redhat.com>
Wed, 3 Jul 2019 15:59:24 +0000 (16:59 +0100)
commit3d9be6f531db395a5ad940ef06e56d849f4de646
treebfb290fae432f5dcc6186dba817d093ba5b872d6
parent41fc454c915057d9c5536617370c5eb2a5f71323
Teach gdb::option about string options

A following patch will make the "pipe" command use the gdb::option
framework for option processing.  However, "pipe"'s only option today
is a string option, "-d DELIM", and gdb::option does not support
string options yet.

This commit adds support for string options, mapped to var_string.
For now, a string is parsed up until the first whitespace.  I imagine
that we'll need to add support for quoting so that we could do:

 (gdb) cmd -option 'some -string'

without gdb confusing the "-string" for an option.

This doesn't seem important for pipe, so I'm leaving it for another
day.

One thing I'm not happy with, is that the string data is managed as a
raw malloc-allocated char *, which means that we need to xfree it
manually.  This is because var_string settings work that way too.
Although with var_string settings we're leaking the strings at gdb
exit, that was never really a problem.  For options though, leaking is
undesirable.

I think we should tackle that for both settings and options at the
same time, so for now I'm just managing the malloced data manually.
It's a bit ugly in option_def_and_value, but at least that's hidden
from view.

For testing, this adds a new "-string" option to "maint
test-settings", and then tweaks gdb.base/options.exp to exercise it.

gdb/ChangeLog:
2019-07-03  Pedro Alves  <palves@redhat.com>

* cli/cli-option.c (union option_value) <string>: New field.
(struct option_def_and_value): Add ctor, move ctor, dtor and
use DISABLE_COPY_AND_ASSIGN.
(option_def_and_value::clear_value): New.
(parse_option, save_option_value_in_ctx, get_val_type_str)
(add_setshow_cmds_for_options): Handle var_string.
* cli-option.h (union option_def::var_address) <string>: New
field.
(struct string_option_def): New.
* maint-test-options.c (struct test_options_opts): Add default
ctor and use DISABLE_COPY_AND_ASSIGN.
<string_opt>: New field.
(test_options_opts::~test_options_opts): New.
(test_options_opts::dump): Also dump "-string".
(test_options_option_defs): Install "string.

gdb/testsuite/ChangeLog:
2019-07-03  Pedro Alves  <palves@redhat.com>

* gdb.base/options.exp (expect_none, expect_flag, expect_bool)
(expect_integer): Adjust to expect "-string".
(expect_string): New.
(all_options): Expect "-string".
(test-flag, test-boolean): Adjust to expect "-string".
(test-string): New proc.
(top level): Call it.
gdb/ChangeLog
gdb/cli/cli-option.c
gdb/cli/cli-option.h
gdb/maint-test-options.c
gdb/testsuite/ChangeLog
gdb/testsuite/gdb.base/options.exp