Allow a condition-case handler on the form (:success BODY) to be
specified as the success continuation of the protected form, with
the specified variable bound to its result.

* src/eval.c (Fcondition_case): Update the doc string.
(internal_lisp_condition_case): Implement in interpreter.
(syms_of_eval): Defsym :success.
* lisp/emacs-lisp/bytecomp.el (byte-compile-condition-case):
Implement in byte-compiler.
* lisp/emacs-lisp/cl-macs.el (cl--self-tco): Allow self-TCO
from success handler.
* doc/lispref/control.texi (Handling Errors): Update manual.
* etc/NEWS: Announce.
* test/lisp/emacs-lisp/bytecomp-tests.el (bytecomp-tests--test-cases)
(bytecomp-condition-case-success):
* test/lisp/emacs-lisp/cl-macs-tests.el (cl-macs--labels):
Add test cases.

* lisp/net/tramp-sh.el (tramp-do-copy-or-rename-file-out-of-band):
Use `start-process' instead of `start-process-shell-command'.
(tramp-make-copy-program-file-name): Do not quote `localname'.

* test/lisp/net/tramp-tests.el (tramp-method-out-of-band-p): Declare.
(tramp--test-windows-nt-and-batch-p)
(tramp--test-windows-nt-and-pscp-psftp-p): Remove, and also all callees.
(tramp--test-windows-nt-and-out-of-band-p)
(tramp--test-windows-nt-and-scp-p): New defuns.
(tramp-test17-dired-with-wildcards)
(tramp-test40-special-characters)
(tramp-test40-special-characters-with-stat)
(tramp-test40-special-characters-with-perl)
(tramp-test40-special-characters-with-ls, tramp-test41-utf8)
(tramp-test41-utf8-with-stat, tramp-test41-utf8-with-perl)
(tramp-test41-utf8-with-ls): Use them.

* src/character.c (Fstring_width, lisp_string_width): Accept two
optional arguments FROM and TO, to indicate the substring to be
considered.
(Fstring_width): Add caveats in the doc string about display
features ignored by the function.  (Bug#47712)
* src/character.h (lisp_string_width): Update prototype.
* src/editfns.c (styled_format): Adjust call of lisp_string_width
to its changed signature.

* test/src/character-tests.el (character-test-string-width): New
file with tests for 'string-width'.

* doc/lispref/display.texi (Size of Displayed Text): Document
caveats of using 'string-width'.

* etc/NEWS: Announce the change.

* lisp/tar-mode.el (tar-header-block-summarize): Use it.
(tar-grind-file-mode): Declare obsolete.

This is useful when starting Emacs with a Seccomp filter enabled,
e.g. using 'bwrap'.

* lib-src/seccomp-filter.c (main): Generate new Seccomp files.

* lib-src/Makefile.in (all)
(seccomp-filter.bpf seccomp-filter.pfc seccomp-filter-exec.bpf
seccomp-filter-exec.pfc): Generate new Seccomp files.

* .gitignore: Ignore new Seccomp files.

* test/src/emacs-tests.el (emacs-tests/bwrap/allows-stdout): New unit
test.

* lisp/calculator.el (calculator-string-to-number):
The last bugfix changed the code to just blindly replace ".e".  This
has some minor problems like making "-." parse as 0.0 instead of -0.0,
and ".1.e1" is parsed as 1 instead of 0.1.  Instead, replace the first
"." that is followed by a non-digit with ".0".  Since this has had
several problems over the years, add some tests too.  (Also, restore
the original if-indentation style.)

* lisp/emacs-lisp/cconv.el (cconv-convert): Typo.
* test/lisp/emacs-lisp/bytecomp-tests.el (bytecomp-tests--test-cases):
Add test case.

The binary uses the 'seccomp' helper library.  The library isn't
needed to load the generated Secure Computing filter.

* configure.ac: Check for 'seccomp' header and library.

* lib-src/seccomp-filter.c: New helper binary to generate a generic
Secure Computing filter for GNU/Linux.

* lib-src/Makefile.in (DONT_INSTALL): Add 'seccomp-filter' helper
binary if possible.
(all): Add Secure Computing filter file if possible.
(seccomp-filter$(EXEEXT)): Compile helper binary.
(seccomp-filter.bpf seccomp-filter.pfc): Generate filter files.

* test/src/emacs-tests.el (emacs-tests/seccomp/allows-stdout)
(emacs-tests/seccomp/forbids-subprocess): New unit tests.

* test/Makefile.in (src/emacs-tests.log): Add dependency on the helper
binary.

When passing this option on GNU/Linux, Emacs installs a Secure
Computing kernel system call filter.  See Bug#45198.

* configure.ac: Check for seccomp header.

* src/emacs.c (usage_message): Document --seccomp option.
(emacs_seccomp): New wrapper for 'seccomp' syscall.
(load_seccomp, maybe_load_seccomp): New helper functions.
(main): Potentially load seccomp filters during startup.
(standard_args): Add --seccomp option.

* lisp/startup.el (command-line): Detect and ignore --seccomp option.

* test/src/emacs-tests.el (emacs-tests/seccomp/absent-file)
(emacs-tests/seccomp/empty-file)
(emacs-tests/seccomp/file-too-large)
(emacs-tests/seccomp/invalid-file-size): New unit tests.
(emacs-tests--with-temp-file): New helper macro.

* etc/NEWS: Document new --seccomp option.

Edebug doesn't deal well with backtracking out of definitions, see
Bug#41988.  Rather than trying to support this rare situation (e.g. by
implementing a multipass parser), prevent it by adding an implicit
gate.

* lisp/emacs-lisp/edebug.el (edebug--match-&-spec-op): Disable
backtracking when hitting a &define keyword.

* test/lisp/emacs-lisp/edebug-tests.el
(edebug-tests-duplicate-&define): New unit test.
(edebug-tests--duplicate-&define): New helper macro.

* doc/lispref/edebug.texi (Backtracking): Mention &define in the list
of constructs that disable backtracking.

* etc/NEWS: Document new behavior.