Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Sync sh(1) in stable/10 to head.

This is a MFC of all the commits listed below.

My original goal of this change was to only merge the move of the tests
from tools/regression/bin/ into the new layout (which include tests for
sh(1) and other tools as well). However, doing so is tricky due to the
ongoing work in sh(1) and, especially, the many changes to its tests
since stable/10 was first branched.

Merging everything is the simplest way to achieve this goal and, as a
bonus point, we get various fixes and miscellaneous improvements into
the branch.

Per jilles' suggestion, I'm avoiding the merge of a couple of changes
(r256850 and r257506) that required depending kernel changes. I'm also
avoiding very recent changes that have not had a long enough time to be
validated in current.

This is "make tinderbox" clean.

r256735 sh: Remove one syscall when waiting for a foreground job.
r257399 sh: Allow trapping SIGINT/SIGQUIT after ignore because of '&'.
r257504 sh: Reorder union node to reduce its size on 64-bit platforms.
r257920 sh: Add a test case for would-be assignments that are not due to quoting.
r257929 sh: Properly quote alias output from command -v.
r258489 sh: Add tests for the </dev/null implicit in a background command.
r258533 sh: Add more tests for the </dev/null implicit in a background command.
r258535 sh: Make <&0 disable the </dev/null implicit in a background command.
r258776 sh: Prefer memcpy() to strcpy() in most cases. Remove the scopy macro.
r259047 sh: Split set -x output into a separate function.
r259210 Migrate tools/regression/bin/ tests to the new layout.
r259844 sh: Remove an unused variable.
r259846 sh: Initialize OPTIND=1 even if it came from the environment.
r259874 sh: Simplify code related to PPID variable.
r259946 sh: Don't check input for non-whitespace if history is disabled.
r260246 sh(1): Discourage use of -e.
r260506 Run the sh(1) and test(1) tests as unprivileged.
r260586 Mark the bin/pax tests as requiring perl.
r260634 Use TAP_TESTS_PERL to register the legacy_test in bin/pax.
r260635 Replace hand-crafted Kyuafiles with automatic generation.
r260654 sh: Remove SIGWINCH handler and just check for resize before every read.
r261121 sh: Add test for nested alias.
r261125 sh: Solve the alias recursion problem in a less hackish way.
r261141 sh: Do not depend on parse/execute split in new alias test.
r261160 sh: Add tests for alias names after another alias.
r261192 sh: Allow aliases to force alias substitution on the following word.
r262533 sh: Make expari() static.
r262565 sh: Do not corrupt internal representation if LINENO inner expansion fails.
r262697 sh: Simplify expari().

Reviewed by: jilles

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

sh: Fix race condition with signals and wait or set -T.

The change in r238888 was incomplete. It was still possible for a trapped
signal to arrive before the shell went to sleep (sigsuspend()) because a
check was missing or because the signal arrived before in_waitcmd was set.

On SMP, this bug sometimes caused the builtins/wait4.0 test to take 1 second
to execute; it then might or might not fail. On UP, the test almost always
failed.

sh: If a SIGINT or SIGQUIT interrupts "wait", return status 128+sig.

sh: Fix EINTR race condition in "wait" and "set -T" using sigsuspend().

When waiting for child processes using "wait" or if "set -T" is in effect, a
signal interrupts the wait. Make sure there is no window where the signal
handler may be invoked (setting a flag) just before going to sleep.

There is a similar race condition in the shell language, but scripts can
avoid it by exiting from the trap handler or enforcing synchronization using
a fifo.

If SIGCHLD is not trapped, a signal handler must be installed for it. Only
install this handler for the duration of the wait to avoid triggering
unexpected [EINTR] errors elsewhere.

Note that for some reason only SIGINT and SIGQUIT interrupt a "wait"
command. This remains the case.

sh: Fix duplicate prototypes for builtins.

Have mkbuiltins write the prototypes for the *cmd functions to builtins.h
instead of builtins.c and include builtins.h in more .c files instead of
duplicating prototypes for *cmd functions in other headers.

sh: Make exit without parameters from EXIT trap POSIX-compliant.

It should use the original exit status, just like falling off the
end of the trap handler.

Outside an EXIT trap, 'exit' is still equivalent to 'exit $?'.

sh: Add some __dead2 to indicate functions that do not return.

Don't skip forking for an external command if any traps are active.

Example:
sh -c '(trap "echo trapped" EXIT; sleep 3)'
now correctly prints "trapped".

With this check, it is no longer necessary to check for -T
explicitly in that case.

This is a useful bugfix by itself and also important because I plan to
skip forking more often.

PR: bin/113860 (part of)
PR: bin/74404 (part of)
Reviewed by: stefanf
Approved by: ed (mentor)

Remove clause 3 from the UCB licenses.

OK'ed by: imp, core

Avoid calling el_resize() from a signal handler, even though libedit
itself does that if you set EL_SIGNAL. Instead, set a flag and check it
before calling el_gets(). This is safer, but slower to respond to changes.

Pointed out by: mp

o __P has been reoved
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
they already are.
o Change
int
foo() {
...
to
int
foo(void)
{
...

$Id$ -> $FreeBSD$

Do not exit on SIGINT in non-interactive shells, fixes PR 1206,
i.e. this makes emacs usable from system(3). Programs called from
shellscripts are now required to exit with proper signal status. That
means, they have to kill themself. Exiting with faked numerical exit
code is not sufficient.

Exit with proper signal status if script exits on signal.

Make the wait builtin interruptable, both with and without traps set.

Use volatile sig_atomic_t where (and only where) appropriate.

(Almost) fix printing of newlines on SIGINT.

Make traps setable from trap handlers. This is needed for shellscripts
that catch SIGINT for cleanup work but intend to exit on it, hance
have to kill themself from a trap handler. I.e. mkdep.

While I'm at it, make it -Wall clean. -Wall is not enabled in
Makefile, since vararg warnx() macro calls in usr.bin/printf/printf.c
are not -Wall-able.
PR: 1206
Obtained from: Basic SIGINT fix from Bruce Evans

Fixed some type and value mismatches. setsignal() returned a bogusly
cast value that was always ignored. Rev.1.9 of trap.c made this
more bogus by returning a semantically different value after calling
siginterrupt(). Avoid these problems by not returning a value.

Revert $FreeBSD$ to $Id$

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Merge in NetBSD mods and -Wall cleaning.

Obtained from: NetBSD, me

Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault... mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do. The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter

Added $Id$

This commit was generated by cvs2svn to compensate for changes in r1556,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite bin Sources