Previously, the observers attached to an observable were always notified
in the order in which they had been attached. That order is not easily
controlled, because observers are typically attached in _initialize_*
functions, which are called in an undefined order.
However, an observer may require that another observer attached only
later is called before itself is.
Therefore, extend the 'observable' class to allow explicitly specifying
dependencies when attaching observers, by adding the possibility to
specify tokens for observers that it depends on.
To make sure dependencies are notified before observers depending on
them, the vector holding the observers is sorted in a way that
dependencies come before observers depending on them. The current
implementation for sorting uses the depth-first search algorithm for
topological sorting as described at [1].
Extend the observable unit tests to cover this case as well. Check that
this works for a few different orders in which the observers are
attached.
This newly introduced mechanism to explicitly specify dependencies will
be used in a follow-up commit.
[1] https://en.wikipedia.org/wiki/Topological_sorting#Depth-first_search
Tested on x86_64-linux (Debian testing).
gdb/ChangeLog:
* unittests/observable-selftests.c (dependency_test_counters):
New.
(observer_token0, observer_token1, observer_token2,
observer_token3, observer_token4, observer_token5): New.
(struct dependency_observer_data): New struct.
(observer_dependency_test_callback): New function.
(test_observers): New.
(run_dependency_test): New function.
(test_dependency): New.
(_initialize_observer_selftest): Register dependency test.
gdbsupport/ChangeLog:
* observable.h (class observable): Extend to allow specifying
dependencies between observers, keep vector holding observers
sorted so that dependencies are notified before observers
depending on them.
Change-Id: I5399def1eeb69ca99e28c9f1fdf321d78b530bdb
Switch observer to use the "new" debug printf mechanism and sprinkle a
few debug prints. Here's a small example of the output with "infrun"
and "observer" debug output enabled:
[infrun] proceed: enter
[observer] notify: start: observable target_resumed notify() called
[observer] notify: start: calling observer mi-interp of observable target_resumed
[observer] notify: end: calling observer mi-interp of observable target_resumed
[observer] notify: start: calling observer py-inferior of observable target_resumed
[observer] notify: end: calling observer py-inferior of observable target_resumed
[observer] notify: end: observable target_resumed notify() called
...
gdbsupport/ChangeLog:
* observable.h (observer_debug_printf,
OBSERVER_SCOPED_DEBUG_START_END): New.
(class observable) <notify, attach>: Use them.
Change-Id: If3ae4b6b65450ca3b7cae56698a87fc526688b86
Give a name to each observer, this will help produce more meaningful
debug message.
gdbsupport/ChangeLog:
* observable.h (class observable) <struct observer> <observer>:
Add name parameter.
<name>: New field.
<attach>: Add name parameter, update all callers.
Change-Id: Ie0cc4664925215b8d2b09e026011b7803549fba0
Instead of using a pair. This allows keeping more data per observer in
a structured way, and using field names is clearer than first/second.
gdbsupport/ChangeLog:
* observable.h (class observable) <struct observer>: New.
<detach, notify>: Update.
<m_observers>: Change type to vector of observers.
Change-Id: Iadf7d1fa25049cfb089e6b1b429ddebc548825ab
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.
This patch moves the gdbsupport directory to the top level. This is
the next step in the ongoing project to move gdbserver to the top
level.
The bulk of this patch was created by "git mv gdb/gdbsupport gdbsupport".
This patch then adds a build system to gdbsupport and wires it into
the top level. Then it changes gdb to use the top-level build.
gdbserver, on the other hand, is not yet changed. It still does its
own build of gdbsupport.
ChangeLog
2020-01-14 Tom Tromey <tom@tromey.com>
* src-release.sh (GDB_SUPPORT_DIRS): Add gdbsupport.
* MAINTAINERS: Add gdbsupport.
* configure: Rebuild.
* configure.ac (configdirs): Add gdbsupport.
* gdbsupport: New directory, move from gdb/gdbsupport.
* Makefile.def (host_modules, dependencies): Add gnulib.
* Makefile.in: Rebuild.
gdb/ChangeLog
2020-01-14 Tom Tromey <tom@tromey.com>
* nat/x86-linux-dregs.c: Include configh.h.
* nat/linux-ptrace.c: Include configh.h.
* nat/linux-btrace.c: Include configh.h.
* defs.h: Include config.h, bfd.h.
* configure.ac: Don't source common.host.
(CONFIG_OBS, CONFIG_SRCS): Remove gdbsupport files.
* configure: Rebuild.
* acinclude.m4: Update path.
* Makefile.in (SUPPORT, LIBSUPPORT, INCSUPPORT): New variables.
(CONFIG_SRC_SUBDIR): Remove gdbsupport.
(INTERNAL_CFLAGS_BASE): Add INCSUPPORT.
(CLIBS): Add LIBSUPPORT.
(CDEPS): Likewise.
(COMMON_SFILES): Remove gdbsupport files.
(HFILES_NO_SRCDIR): Likewise.
(stamp-version): Update path to create-version.sh.
(ALLDEPFILES): Remove gdbsupport files.
gdb/gdbserver/ChangeLog
2020-01-14 Tom Tromey <tom@tromey.com>
* server.h: Include config.h.
* gdbreplay.c: Include config.h.
* configure: Rebuild.
* configure.ac: Don't source common.host.
* acinclude.m4: Update path.
* Makefile.in (INCSUPPORT): New variable.
(INCLUDE_CFLAGS): Add INCSUPPORT.
(SFILES): Update paths.
(version-generated.c): Update path to create-version.sh.
(gdbsupport/%-ipa.o, gdbsupport/%.o): Update paths.
gdbsupport/ChangeLog
2020-01-14 Tom Tromey <tom@tromey.com>
* common-defs.h: Add GDBSERVER case. Update includes.
* acinclude.m4, aclocal.m4, config.in, configure, configure.ac,
Makefile.am, Makefile.in, README: New files.
* Moved from ../gdb/gdbsupport/
Change-Id: I07632e7798635c1bab389bf885971e584fb4bb78
2020-01-14 16:25:02 -07:00
Renamed from gdb/gdbsupport/observable.h (Browse further)
