Convert observers to C++

This converts observers from using a special source-generating script
to be plain C++.  This version of the patch takes advantage of C++11
by using std::function and variadic templates; incorporates Pedro's
patches; and renames the header file to "observable.h" (this change
eliminates the need for a clean rebuild).

Note that Pedro's patches used a template lambda in tui-hooks.c, but
this failed to compile on some buildbot instances (presumably due to
differing C++ versions); I replaced this with an ordinary template
function.

Regression tested on the buildbot.

gdb/ChangeLog
2018-03-19  Pedro Alves  <palves@redhat.com>
	    Tom Tromey  <tom@tromey.com>

	* unittests/observable-selftests.c: New file.
	* common/observable.h: New file.
	* observable.h: New file.
	* ada-lang.c, ada-tasks.c, agent.c, aix-thread.c, annotate.c,
	arm-tdep.c, auto-load.c, auxv.c, break-catch-syscall.c,
	breakpoint.c, bsd-uthread.c, cli/cli-interp.c, cli/cli-setshow.c,
	corefile.c, dummy-frame.c, event-loop.c, event-top.c, exec.c,
	extension.c, frame.c, gdbarch.c, guile/scm-breakpoint.c,
	infcall.c, infcmd.c, inferior.c, inflow.c, infrun.c, jit.c,
	linux-tdep.c, linux-thread-db.c, m68klinux-tdep.c,
	mi/mi-cmd-break.c, mi/mi-interp.c, mi/mi-main.c, objfiles.c,
	ppc-linux-nat.c, ppc-linux-tdep.c, printcmd.c, procfs.c,
	python/py-breakpoint.c, python/py-finishbreakpoint.c,
	python/py-inferior.c, python/py-unwind.c, ravenscar-thread.c,
	record-btrace.c, record-full.c, record.c, regcache.c, remote.c,
	riscv-tdep.c, sol-thread.c, solib-aix.c, solib-spu.c, solib.c,
	spu-multiarch.c, spu-tdep.c, stack.c, symfile-mem.c, symfile.c,
	symtab.c, thread.c, top.c, tracepoint.c, tui/tui-hooks.c,
	tui/tui-interp.c, valops.c: Update all users.
	* tui/tui-hooks.c (tui_bp_created_observer)
	(tui_bp_deleted_observer, tui_bp_modified_observer)
	(tui_inferior_exit_observer, tui_before_prompt_observer)
	(tui_normal_stop_observer, tui_register_changed_observer):
	Remove.
	(tui_observers_token): New global.
	(attach_or_detach, tui_attach_detach_observers): New functions.
	(tui_install_hooks, tui_remove_hooks): Use
	tui_attach_detach_observers.
	* record-btrace.c (record_btrace_thread_observer): Remove.
	(record_btrace_thread_observer_token): New global.
	* observer.sh: Remove.
	* observer.c: Rename to observable.c.
	* observable.c (namespace gdb_observers): Define new objects.
	(observer_debug): Move into gdb_observers namespace.
	(struct observer, struct observer_list, xalloc_observer_list_node)
	(xfree_observer_list_node, generic_observer_attach)
	(generic_observer_detach, generic_observer_notify): Remove.
	(_initialize_observer): Update.
	Don't include observer.inc.
	* Makefile.in (generated_files): Remove observer.h, observer.inc.
	(clean mostlyclean): Likewise.
	(observer.h, observer.inc): Remove targets.
	(SUBDIR_UNITTESTS_SRCS): Add observable-selftests.c.
	(COMMON_SFILES): Use observable.c, not observer.c.
	* .gitignore: Remove observer.h.

gdb/doc/ChangeLog
2018-03-19  Tom Tromey  <tom@tromey.com>

	* observer.texi: Remove.

gdb/testsuite/ChangeLog
2018-03-19  Tom Tromey  <tom@tromey.com>

	* gdb.gdb/observer.exp: Remove.

4 files changed, 22 insertions, 22 deletions

diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c
index 5ac3f98..d654b92 100644
--- a/gdb/python/py-breakpoint.c
+++ b/gdb/python/py-breakpoint.c
@@ -25,7 +25,7 @@
 #include "breakpoint.h"
 #include "gdbcmd.h"
 #include "gdbthread.h"
-#include "observer.h"
+#include "observable.h"
 #include "cli/cli-script.h"
 #include "ada-lang.h"
 #include "arch-utils.h"
@@ -1086,9 +1086,9 @@ gdbpy_initialize_breakpoints (void)
 			      (PyObject *) &breakpoint_object_type) < 0)
     return -1;
 
-  observer_attach_breakpoint_created (gdbpy_breakpoint_created);
-  observer_attach_breakpoint_deleted (gdbpy_breakpoint_deleted);
-  observer_attach_breakpoint_modified (gdbpy_breakpoint_modified);
+  gdb::observers::breakpoint_created.attach (gdbpy_breakpoint_created);
+  gdb::observers::breakpoint_deleted.attach (gdbpy_breakpoint_deleted);
+  gdb::observers::breakpoint_modified.attach (gdbpy_breakpoint_modified);
 
   /* Add breakpoint types constants.  */
   for (i = 0; pybp_codes[i].name; ++i)
diff --git a/gdb/python/py-finishbreakpoint.c b/gdb/python/py-finishbreakpoint.c
index 7a05ad3..b3978f7 100644
--- a/gdb/python/py-finishbreakpoint.c
+++ b/gdb/python/py-finishbreakpoint.c
@@ -26,7 +26,7 @@
 #include "gdbthread.h"
 #include "arch-utils.h"
 #include "language.h"
-#include "observer.h"
+#include "observable.h"
 #include "inferior.h"
 #include "block.h"
 #include "location.h"
@@ -416,8 +416,8 @@ gdbpy_initialize_finishbreakpoints (void)
 			      (PyObject *) &finish_breakpoint_object_type) < 0)
     return -1;
 
-  observer_attach_normal_stop (bpfinishpy_handle_stop);
-  observer_attach_inferior_exit (bpfinishpy_handle_exit);
+  gdb::observers::normal_stop.attach (bpfinishpy_handle_stop);
+  gdb::observers::inferior_exit.attach (bpfinishpy_handle_exit);
 
   return 0;
 }
diff --git a/gdb/python/py-inferior.c b/gdb/python/py-inferior.c
index 564aa79..d199aaa 100644
--- a/gdb/python/py-inferior.c
+++ b/gdb/python/py-inferior.c
@@ -22,7 +22,7 @@
 #include "gdbthread.h"
 #include "inferior.h"
 #include "objfiles.h"
-#include "observer.h"
+#include "observable.h"
 #include "python-internal.h"
 #include "arch-utils.h"
 #include "language.h"
@@ -926,18 +926,18 @@ gdbpy_initialize_inferior (void)
   infpy_inf_data_key =
     register_inferior_data_with_cleanup (NULL, py_free_inferior);
 
-  observer_attach_new_thread (add_thread_object);
-  observer_attach_thread_exit (delete_thread_object);
-  observer_attach_normal_stop (python_on_normal_stop);
-  observer_attach_target_resumed (python_on_resume);
-  observer_attach_inferior_call_pre (python_on_inferior_call_pre);
-  observer_attach_inferior_call_post (python_on_inferior_call_post);
-  observer_attach_memory_changed (python_on_memory_change);
-  observer_attach_register_changed (python_on_register_change);
-  observer_attach_inferior_exit (python_inferior_exit);
-  observer_attach_new_objfile (python_new_objfile);
-  observer_attach_inferior_added (python_new_inferior);
-  observer_attach_inferior_removed (python_inferior_deleted);
+  gdb::observers::new_thread.attach (add_thread_object);
+  gdb::observers::thread_exit.attach (delete_thread_object);
+  gdb::observers::normal_stop.attach (python_on_normal_stop);
+  gdb::observers::target_resumed.attach (python_on_resume);
+  gdb::observers::inferior_call_pre.attach (python_on_inferior_call_pre);
+  gdb::observers::inferior_call_post.attach (python_on_inferior_call_post);
+  gdb::observers::memory_changed.attach (python_on_memory_change);
+  gdb::observers::register_changed.attach (python_on_register_change);
+  gdb::observers::inferior_exit.attach (python_inferior_exit);
+  gdb::observers::new_objfile.attach (python_new_objfile);
+  gdb::observers::inferior_added.attach (python_new_inferior);
+  gdb::observers::inferior_removed.attach (python_inferior_deleted);
 
   membuf_object_type.tp_new = PyType_GenericNew;
   if (PyType_Ready (&membuf_object_type) < 0)
diff --git a/gdb/python/py-unwind.c b/gdb/python/py-unwind.c
index 906a004..1d235fc 100644
--- a/gdb/python/py-unwind.c
+++ b/gdb/python/py-unwind.c
@@ -23,7 +23,7 @@
 #include "gdb_obstack.h"
 #include "gdbcmd.h"
 #include "language.h"
-#include "observer.h"
+#include "observable.h"
 #include "python-internal.h"
 #include "regcache.h"
 #include "valprint.h"
@@ -662,7 +662,7 @@ gdbpy_initialize_unwind (void)
         &setdebuglist, &showdebuglist);
   pyuw_gdbarch_data
       = gdbarch_data_register_post_init (pyuw_gdbarch_data_init);
-  observer_attach_architecture_changed (pyuw_on_new_gdbarch);
+  gdb::observers::architecture_changed.attach (pyuw_on_new_gdbarch);
 
   if (PyType_Ready (&pending_frame_object_type) < 0)
     return -1;