[PATCH 00/24] gdb::option framework, "print -OPT", other cmd options

[Pedro Alves <palves@redhat.com>]

This all started a couple years ago with the idea that one reason
people sometimes complain about gdb's defaults, such as "set print
object" or "set print static-members" is that we don't have an easy
way to override the global print settings.

I.e., how if we had options support in the print command, so you could
do this:

  (gdb) print -pretty obj

instead of:

  (gdb) set print pretty on
  (gdb) print obj
  (gdb) set print pretty off

then the defaults, while they'd still matter, wouldn't matter so much.

Back then, I experimented with that, and got a prototype up and
running.  Other priorities were put in front of it so I never managed
to finish it... until now.  The reason I picked it up again, is that
this addresses part of the same motivation that led to Philippe's "/"
command.  I don't necessarily think that the solutions are orthogonal,
but I do think that having this feature in might affect how we look at
the "/"-command idea.  Particularly, I'm not sold on the way the
feature's user interface is designed.

I'm a strong believer of TAB-completion driving the CLI, and that is
one of the reasons why I like this patchset.  If you're like me,
you're pressing TAB all the time.  It allows dynamic discovery of
options/features, and makes it not a problem to have longer option
names:

 (gdb) p -[TAB]
 -address         -elements        -pretty          -symbol
 -array           -null-stop       -repeats         -union
 -array-indexes   -object          -static-members  -vtbl

The approach I took is that command options have a similar syntax and
names to the global set settings.  The above should be familiar, if
you're familiar with the "set print" settings:

  (gdb) set print[TAB]
  address                max-symbolic-offset    symbol
  array                  null-stop              symbol-filename
  array-indexes          object                 symbol-loading
  asm-demangle           pascal_static-members  thread-events
  demangle               pretty                 type
  elements               raw                    union
  entry-values           repeats                vtbl
  frame-arguments        sevenbit-strings       
  inferior-events        static-members         

So we have boolean, integer and enum options, just like we have the
"set" command counterpart types.  In fact, the data structures used to
describe a command's options can (and are) used to install the
corresponding "set" commands.

This results in options like:

 (gdb) print -elements 100 -object off -- *myobj
 (gdb) backtrace -frame-arguments scalars
 (gdb) frame apply all -past-main

Also, command options are abbreviatable, boolean arguments are
optional (on is assumed), and you can write 0/1 instead of on/off too,
so you could replace the above with

 (gdb) print -e 100 -o 0 -- *myobj
 (gdb) backtrace -fr s
 (gdb) f ap a -past-m

BTW, you'll notice that the framework doesn't split arguments in an
array of arguments, getopt-/buildargv- style.  The reason for that is
that many commands in gdb accept raw, unformatted arguments,
expressions, and we can't split those up around whitespace.

So the series adds fixes a number of latent bugs exposed while writing
this, the options infrastructure proper along with its testsuite
(patch #12), and converts a number of commands to use the
infrastructure: "print"/"compile print", "compile code/file",
"backtrace", and "thread/frame apply" & friends.

Patch #9 adds testing of the "set"/"show" commands' parsing/completion
mechanics.

For print in particular, I settled on requiring "--" if you specify
any option.  I'm open to opinions otherwise, but please read through
the series, and particularly patch #13 for more details around that
choice.

Documentation is most in the last patch of the series, except there's
another bit in patch #09, which could be a standalone patch.

Pedro Alves (24):
  Fix latent bug in custom word point completion handling
  Fix latent bug with custom word point completers
  Fix TID parser bug
  Make check_for_argument skip whitespace after arg itself
  Allow "unlimited" abbreviations
  Fix "set enum-command value garbage"
  Remove "show" command completers
  gdb.base/settings.exp: Fix comment typo
  New set/show testing framework (gdb.base/settings.exp)
  boolean/auto-boolean commands, make "o" ambiguous
  number_or_range_parser::get_number, don't treat "1 -" as a range
  Introduce generic command options framework
  Make "print" and "compile print" support -OPT options
  Migrate rest of compile commands to new options framework
  Introduce rename_cmd
  Make "backtrace" support -OPT options
  "backtrace full/no-filters/hide" completer
  lib/completion-support.exp: Add test_gdb_completion_offers_commands
  Introduce complete_command
  Make "frame apply" support -OPT options
  "thread apply 1 -- -" vs "frame apply level 0 -- -"
  Make "thread apply" use the gdb::option framework
  Delete parse_flags/parse_flags_qcs
  NEWS and manual changes for command options changes

 gdb/doc/gdb.texinfo                      | 338 +++++++++--
 gdb/NEWS                                 |  97 ++++
 gdb/Makefile.in                          |   3 +
 gdb/ax-gdb.c                             |   2 -
 gdb/breakpoint.c                         |   5 +-
 gdb/cli/cli-decode.c                     | 183 ++++--
 gdb/cli/cli-decode.h                     |   4 +
 gdb/cli/cli-option.c                     | 732 ++++++++++++++++++++++++
 gdb/cli/cli-option.h                     | 335 +++++++++++
 gdb/cli/cli-setshow.c                    | 287 ++++++----
 gdb/cli/cli-setshow.h                    |  27 +
 gdb/cli/cli-utils.c                      | 124 +++--
 gdb/cli/cli-utils.h                      |  62 +--
 gdb/command.h                            |   5 +
 gdb/compile/compile.c                    | 215 ++++---
 gdb/completer.c                          |  84 ++-
 gdb/completer.h                          |  20 +-
 gdb/cp-valprint.c                        |  57 --
 gdb/frame.c                              |  84 +--
 gdb/frame.h                              |  55 +-
 gdb/maint-test-options.c                 | 460 +++++++++++++++
 gdb/maint-test-settings.c                | 257 +++++++++
 gdb/mi/mi-cmd-stack.c                    |  23 +-
 gdb/printcmd.c                           |  94 +++-
 gdb/python/py-framefilter.c              |   3 +-
 gdb/stack.c                              | 627 ++++++++++++++++-----
 gdb/stack.h                              |   5 +
 gdb/testsuite/gdb.base/completion.exp    |   2 +-
 gdb/testsuite/gdb.base/options.c         |  33 ++
 gdb/testsuite/gdb.base/options.exp       | 923 +++++++++++++++++++++++++++++++
 gdb/testsuite/gdb.base/settings.c        |  23 +
 gdb/testsuite/gdb.base/settings.exp      | 536 ++++++++++++++++++
 gdb/testsuite/gdb.compile/compile.exp    |  15 +-
 gdb/testsuite/gdb.multi/tids.exp         |  16 +-
 gdb/testsuite/lib/completion-support.exp |  66 ++-
 gdb/thread.c                             | 285 +++++++---
 gdb/tid-parse.c                          |  16 +-
 gdb/tid-parse.h                          |   3 +
 gdb/unittests/cli-utils-selftests.c      | 133 -----
 gdb/valprint.c                           | 259 ++++++---
 gdb/valprint.h                           |  20 +-
 41 files changed, 5563 insertions(+), 955 deletions(-)
 create mode 100644 gdb/cli/cli-option.c
 create mode 100644 gdb/cli/cli-option.h
 create mode 100644 gdb/maint-test-options.c
 create mode 100644 gdb/maint-test-settings.c
 create mode 100644 gdb/testsuite/gdb.base/options.c
 create mode 100644 gdb/testsuite/gdb.base/options.exp
 create mode 100644 gdb/testsuite/gdb.base/settings.c
 create mode 100644 gdb/testsuite/gdb.base/settings.exp

-- 
2.14.5