Provide an option to run commands via sh -c

The new flag "shell" instructs pies to run the command marked with it
as '/bin/sh -c $command'. Alternative shell can be supplied ising the
'program' statement.

This is useful if the command line uses shell-specific features (command
or variable expansion, redirection, pipes, etc.)

This commit also fixes a bug in the 'env' statement handling: a single
argument with embedded whitespaces was undergoing word splitting and
thus incorrectly handled as multiple arguments.

* NEWS: Document changes.
* doc/pies.texi: Likewise.
* src/comp.c (component_free): Free command.
(component_finish): Split command into argv/argc as directed by the
CF_SHELL flag.
* src/pies.c (_cb_command): Remove. Functionality moved to
component_finish().
(_cb_env): Bugfix. Don't split arguments.
* src/pies.h (CF_SHELL): New flag.
(component) <command>: New member.

* tests/Makefile.am: Add new tests.
* tests/testsuite.at: Add new tests.
* tests/aux/respawn: Change default timeout to 1 second.
* tests/respawn.at: Minor change.
* tests/shell.at: New test.

1 files changed, 58 insertions, 0 deletions

diff --git a/tests/shell.at b/tests/shell.at
new file mode 100644
index 0000000..0ef2271
--- /dev/null
+++ b/tests/shell.at
@@ -0,0 +1,58 @@
+# This file is part of GNU pies testsuite. -*- Autotest -*-
+# Copyright (C) 2016-2019 Sergey Poznyakoff
+#
+# GNU pies is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU pies is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU pies.  If not, see <http://www.gnu.org/licenses/>.
+
+AT_SETUP([flags shell])
+
+AT_CHECK([
+PIES_XFAIL_CHECK
+PIES_CONTROL_INIT
+outfile=$PWD/respawn.out
+cat > pies.conf <<_EOT
+component test {
+        mode respawn;
+        flags shell;
+        command "$auxdir/respawn -tag respawn > $outfile";
+}
+_EOT
+
+pies --config-file control.conf --config-file pies.conf
+
+n=0
+while :
+do
+    if test -f $outfile; then
+        lines=`wc -l $outfile | awk '{print $1}'`
+        if test "$lines" -ge 2 ; then
+            break
+        fi
+    fi  
+    sleep 1
+    n=$(($n + 1))
+    if test $n -gt 35; then
+        echo >&2 "timed out"
+        break
+    fi
+done
+
+PIES_STOP
+head -n3 $outfile
+],
+[0],
+[respawn: start
+respawn: stop
+])
+
+AT_CLEANUP