pipefail.functions

# This file is part of shellfire core. It is subject to the licence terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/shellfire-dev/core/master/COPYRIGHT. No part of shellfire core, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
# Copyright © 2014-2015 The developers of shellfire core. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/shellfire-dev/core/master/COPYRIGHT.


#   Original Copyright (c) 2003-2005, Joe Halpin <j.p.h@comcast.net>
#   Modified from http://cfajohnson.com/shell/cus-faq-2.html#Q11
#   Original permissively licensed
#   Modifications Copyright © 2014-2015 The developers of shellfire core. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/shellfire-dev/core/master/COPYRIGHT.
# Uses the file descriptors 3 and 4
# Run as com1 \| com2 \| com3
core_pipefail_execute()
{
	_core_pipefail_execute_unsetPipestatusVariablesFromPreviousRun
	
	local index=1
	local pipelineCommand=''
	local k=1
	local l=''
	local a=''
	for a in "$@"
	do
		if [ "$a" = '|' ]; then
			pipelineCommand="$pipelineCommand { $l "'3>&-
echo "core_pipefail_PIPESTATUS_'$index'=$?" >&3
} 4>&- |'
			index=$((index + 1))
			l=''
		else
			l="$l \"\$$k\""
		fi
		k=$((k + 1))
	done
	pipelineCommand="$pipelineCommand $l"' 3>&- >&4 4>&-
echo "core_pipefail_PIPESTATUS_'$index'=$?"'
	
	core_message DEBUG "About to execute pipeline command: '$pipelineCommand'"
	
	exec 4>&1
	eval "$(exec 3>&1; eval "$pipelineCommand")"
	exec 4>&-
	
	local exitCode
	_core_pipefail_execute_setPipestatusVariablesAndExitCode
	return $exitCode
}

_core_pipefail_execute_unsetPipestatusVariablesFromPreviousRun()
{
	local index=1
	while core_variable_isSet core_pipefail_PIPESTATUS_$index
	do
		core_variable_unset core_pipefail_PIPESTATUS_$index
		index=$((index + 1))
	done
}

_core_pipefail_execute_setPipestatusVariablesAndExitCode()
{
	local index=1
	local core_variable_indirectValue_result
	while core_variable_isSet core_pipefail_PIPESTATUS_$index
	do
		core_variable_indirectValue core_pipefail_PIPESTATUS_$index
		if [ $core_variable_indirectValue_result -ne 0 ]; then
			exitCode=1
			return 0
		fi
		index=$((index + 1))
	done
}