common/bin/hgforest.sh - edge/openjdk - Git at Google

 #!/bin/sh
 #
 # Copyright (c) 2009, 2014, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License version 2 only, as
 # published by the Free Software Foundation.
 #
 # This code 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
 # version 2 for more details (a copy is included in the LICENSE file that
 # accompanied this code).
 #
 # You should have received a copy of the GNU General Public License version
 # 2 along with this work; if not, write to the Free Software Foundation,
 # Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 #
 # Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 # or visit www.oracle.com if you need additional information or have any
 # questions.
 #

 # Shell script for a fast parallel forest/trees command

 usage() {
       echo "usage: $0 [-h|--help] [-q|--quiet] [-v|--verbose] [-s|--sequential] [--] <command> [commands...]" > ${status_output}
       echo "Environment variables which modify behaviour:"
       echo "   HGFOREST_QUIET      : (boolean) If 'true' then standard output is redirected to /dev/null"
       echo "   HGFOREST_VERBOSE    : (boolean) If 'true' then Mercurial asked to produce verbose output"
       echo "   HGFOREST_SEQUENTIAL : (boolean) If 'true' then repos are processed sequentially. Disables concurrency"
       echo "   HGFOREST_GLOBALOPTS : (string, must begin with space) Additional Mercurial global options"
       echo "   HGFOREST_REDIRECT   : (file path) Redirect standard output to specified file"
       echo "   HGFOREST_FIFOS      : (boolean) Default behaviour for FIFO detection. Does not override FIFOs disabled"
       echo "   HGFOREST_CONCURRENCY: (positive integer) Number of repos to process concurrently"
       echo "   HGFOREST_DEBUG      : (boolean) If 'true' then temp files are retained"
       exit 1
 }

 global_opts="${HGFOREST_GLOBALOPTS:-}"
 status_output="${HGFOREST_REDIRECT:-/dev/stdout}"
 qflag="${HGFOREST_QUIET:-false}"
 vflag="${HGFOREST_VERBOSE:-false}"
 sflag="${HGFOREST_SEQUENTIAL:-false}"
 while [ $# -gt 0 ]
 do
   case $1 in
     -h | --help )
       usage
       ;;

     -q | --quiet )
       qflag="true"
       ;;

     -v | --verbose )
       vflag="true"
       ;;

     -s | --sequential )
       sflag="true"
       ;;

     '--' ) # no more options
       shift; break
       ;;

     -*)  # bad option
       usage
       ;;

      * )  # non option
       break
       ;;
   esac
   shift
 done

 # silence standard output?
 if [ ${qflag} = "true" ] ; then
   global_opts="${global_opts} -q"
   status_output="/dev/null"
 fi

 # verbose output?
 if [ ${vflag} = "true" ] ; then
   global_opts="${global_opts} -v"
 fi

 # Make sure we have a command.
 if [ $# -lt 1 -o -z "${1:-}" ] ; then
   echo "ERROR: No command to hg supplied!"
   usage
 fi

 command="$1"; shift
 command_args="${@:-}"

 # Clean out the temporary directory that stores the pid files.
 tmp=/tmp/forest.$$
 rm -f -r ${tmp}
 mkdir -p ${tmp}


 if [ "${HGFOREST_DEBUG:-false}" = "true" ] ; then
   echo "DEBUG: temp files are in: ${tmp}"
 fi

 # Check if we can use fifos for monitoring sub-process completion.
 echo "1" > ${tmp}/read
 while_subshell=1
 while read line; do
   while_subshell=0
   break;
 done < ${tmp}/read
 rm ${tmp}/read

 on_windows=`uname -s | egrep -ic -e 'cygwin|msys'`

 if [ ${while_subshell} = "1" -o ${on_windows} = "1" ]; then
   # cygwin has (2014-04-18) broken (single writer only) FIFOs
   # msys has (2014-04-18) no FIFOs.
   # older shells create a sub-shell for redirect to while
   have_fifos="false"
 else
   have_fifos="${HGFOREST_FIFOS:-true}"
 fi

 safe_interrupt () {
   if [ -d ${tmp} ]; then
     if [ "`ls ${tmp}/*.pid`" != "" ]; then
       echo "Waiting for processes ( `cat ${tmp}/.*.pid ${tmp}/*.pid 2> /dev/null | tr '\n' ' '`) to terminate nicely!" > ${status_output}
       sleep 1
       # Pipe stderr to dev/null to silence kill, that complains when trying to kill
       # a subprocess that has already exited.
       kill -TERM `cat ${tmp}/*.pid | tr '\n' ' '` 2> /dev/null
       wait
       echo "Interrupt complete!" > ${status_output}
     fi
     rm -f -r ${tmp}
   fi
   exit 130
 }

 nice_exit () {
   if [ -d ${tmp} ]; then
     if [ "`ls -A ${tmp} 2> /dev/null`" != "" ]; then
       wait
     fi
     if [ "${HGFOREST_DEBUG:-false}" != "true" ] ; then
       rm -f -r ${tmp}
     fi
   fi
 }

 trap 'safe_interrupt' INT QUIT
 trap 'nice_exit' EXIT

 subrepos="corba jaxp jaxws langtools jdk hotspot nashorn"
 subrepos_extra="jdk/src/closed jdk/make/closed jdk/test/closed hotspot/make/closed hotspot/src/closed hotspot/test/closed deploy install sponsors pubs"

 # Only look in specific locations for possible forests (avoids long searches)
 pull_default=""
 repos=""
 repos_extra=""
 if [ "${command}" = "clone" -o "${command}" = "fclone" -o "${command}" = "tclone" ] ; then
   # we must be a clone
   if [ ! -f .hg/hgrc ] ; then
     echo "ERROR: Need initial repository to use this script" > ${status_output}
     exit 1
   fi

   # the clone must know where it came from (have a default pull path).
   pull_default=`hg paths default`
   if [ "${pull_default}" = "" ] ; then
     echo "ERROR: Need initial clone with 'hg paths default' defined" > ${status_output}
     exit 1
   fi

   # determine which sub repos need to be cloned.
   for i in ${subrepos} ; do
     if [ ! -f ${i}/.hg/hgrc ] ; then
       repos="${repos} ${i}"
     fi
   done

   pull_default_tail=`echo ${pull_default} | sed -e 's@^.*://[^/]*/\(.*\)@\1@'`

   if [ -n "${command_args}" ] ; then
     # if there is an "extra sources" path then reparent "extra" repos to that path
     if [ "x${pull_default}" = "x${pull_default_tail}" ] ; then
       echo "ERROR: Need initial clone from non-local source" > ${status_output}
       exit 1
     fi
     pull_extra="${command_args}/${pull_default_tail}"

     # determine which extra subrepos need to be cloned.
     for i in ${subrepos_extra} ; do
       if [ ! -f ${i}/.hg/hgrc ] ; then
         repos_extra="${repos_extra} ${i}"
       fi
     done
   else
     if [ "x${pull_default}" = "x${pull_default_tail}" ] ; then
       # local source repo. Clone the "extra" subrepos that exist there.
       for i in ${subrepos_extra} ; do
         if [ -f ${pull_default}/${i}/.hg/hgrc -a ! -f ${i}/.hg/hgrc ] ; then
           # sub-repo there in source but not here
           repos_extra="${repos_extra} ${i}"
         fi
       done
     fi
   fi

   # Any repos to deal with?
   if [ "${repos}" = "" -a "${repos_extra}" = "" ] ; then
     echo "No repositories to process." > ${status_output}
     exit
   fi

   # Repos to process concurrently. Clone does better with low concurrency.
   at_a_time="${HGFOREST_CONCURRENCY:-2}"
 else
   # Process command for all of the present repos
   for i in . ${subrepos} ${subrepos_extra} ; do
     if [ -d ${i}/.hg ] ; then
       repos="${repos} ${i}"
     fi
   done

   # Any repos to deal with?
   if [ "${repos}" = "" ] ; then
     echo "No repositories to process." > ${status_output}
     exit
   fi

   # any of the repos locked?
   locked=""
   for i in ${repos} ; do
     if [ -h ${i}/.hg/store/lock -o -f ${i}/.hg/store/lock ] ; then
       locked="${i} ${locked}"
     fi
   done
   if [ "${locked}" != "" ] ; then
     echo "ERROR: These repositories are locked: ${locked}" > ${status_output}
     exit 1
   fi

   # Repos to process concurrently.
   at_a_time="${HGFOREST_CONCURRENCY:-8}"
 fi

 # Echo out what repositories we do a command on.
 echo "# Repositories: ${repos} ${repos_extra}" > ${status_output}

 if [ "${command}" = "serve" ] ; then
   # "serve" is run for all the repos as one command.
   (
     (
       cwd=`pwd`
       serving=`basename ${cwd}`
       (
         echo "[web]"
         echo "description = ${serving}"
         echo "allow_push = *"
         echo "push_ssl = False"

         echo "[paths]"
         for i in ${repos} ; do
           if [ "${i}" != "." ] ; then
             echo "/${serving}/${i} = ${i}"
           else
             echo "/${serving} = ${cwd}"
           fi
         done
       ) > ${tmp}/serve.web-conf

       echo "serving root repo ${serving}" > ${status_output}

       echo "hg${global_opts} serve" > ${status_output}
       (PYTHONUNBUFFERED=true hg${global_opts} serve -A ${status_output} -E ${status_output} --pid-file ${tmp}/serve.pid --web-conf ${tmp}/serve.web-conf; echo "$?" > ${tmp}/serve.pid.rc ) 2>&1 &
     ) 2>&1 | sed -e "s@^@serve:   @" > ${status_output}
   ) &
 else
   # Run the supplied command on all repos in parallel.

   # n is the number of subprocess started or which might still be running.
   n=0
   if [ ${have_fifos} = "true" ]; then
     # if we have fifos use them to detect command completion.
     mkfifo ${tmp}/fifo
     exec 3<>${tmp}/fifo
   fi

   # iterate over all of the subrepos.
   for i in ${repos} ${repos_extra} ; do
     n=`expr ${n} '+' 1`
     repopidfile=`echo ${i} | sed -e 's@./@@' -e 's@/@_@g'`
     reponame=`echo ${i} | sed -e :a -e 's/^.\{1,20\}$/ &/;ta'`
     pull_base="${pull_default}"

     # regular repo or "extra" repo?
     for j in ${repos_extra} ; do
       if [ "${i}" = "${j}" ] ; then
         # it's an "extra"
         pull_base="${pull_extra}"
       fi
     done

     # remove trailing slash
     pull_base="`echo ${pull_base} | sed -e 's@[/]*$@@'`"

     # execute the command on the subrepo
     (
       (
         if [ "${command}" = "clone" -o "${command}" = "fclone" -o "${command}" = "tclone" ] ; then
           # some form of clone
           clone_newrepo="${pull_base}/${i}"
           parent_path="`dirname ${i}`"
           if [ "${parent_path}" != "." ] ; then
             times=0
             while [ ! -d "${parent_path}" ] ; do  ## nested repo, ensure containing dir exists
               if [ "${sflag}" = "true" ] ; then
                 # Missing parent is fatal during sequential operation.
                 echo "ERROR: Missing parent path: ${parent_path}" > ${status_output}
                 exit 1
               fi
               times=`expr ${times} '+' 1`
               if [ `expr ${times} '%' 10` -eq 0 ] ; then
                 echo "${parent_path} still not created, waiting..." > ${status_output}
               fi
               sleep 5
             done
           fi
           # run the clone command.
           echo "hg${global_opts} clone ${clone_newrepo} ${i}" > ${status_output}
           (PYTHONUNBUFFERED=true hg${global_opts} clone ${clone_newrepo} ${i}; echo "$?" > ${tmp}/${repopidfile}.pid.rc ) 2>&1 &
         else
           # run the command.
           echo "cd ${i} && hg${global_opts} ${command} ${command_args}" > ${status_output}
           cd ${i} && (PYTHONUNBUFFERED=true hg${global_opts} ${command} ${command_args}; echo "$?" > ${tmp}/${repopidfile}.pid.rc ) 2>&1 &
         fi

         echo $! > ${tmp}/${repopidfile}.pid
       ) 2>&1 | sed -e "s@^@${reponame}:   @" > ${status_output}
       # tell the fifo waiter that this subprocess is done.
       if [ ${have_fifos} = "true" ]; then
         echo "${i}" >&3
       fi
     ) &

     if [ "${sflag}" = "true" ] ; then
       # complete this task before starting another.
       wait
     else
       if [ "${have_fifos}" = "true" ]; then
         # check on count of running subprocesses and possibly wait for completion
         if [ ${n} -ge ${at_a_time} ] ; then
           # read will block until there are completed subprocesses
           while read repo_done; do
             n=`expr ${n} '-' 1`
             if [ ${n} -lt ${at_a_time} ] ; then
               # we should start more subprocesses
               break;
             fi
           done <&3
         fi
       else
         # Compare completions to starts
         completed="`(ls -a1 ${tmp}/*.pid.rc 2> /dev/null | wc -l) || echo 0`"
         while [ `expr ${n} '-' ${completed}` -ge ${at_a_time} ] ; do
           # sleep a short time to give time for something to complete
           sleep 1
           completed="`(ls -a1 ${tmp}/*.pid.rc 2> /dev/null | wc -l) || echo 0`"
         done
       fi
     fi
   done
 fi

 # Wait for all subprocesses to complete
 wait

 # Terminate with exit 0 only if all subprocesses were successful
 ec=0
 if [ -d ${tmp} ]; then
   rcfiles="`(ls -a ${tmp}/*.pid.rc 2> /dev/null) || echo ''`"
   for rc in ${rcfiles} ; do
     exit_code=`cat ${rc} | tr -d ' \n\r'`
     if [ "${exit_code}" != "0" ] ; then
       repo="`echo ${rc} | sed -e 's@^'${tmp}'@@' -e 's@/*\([^/]*\)\.pid\.rc$@\1@' -e 's@_@/@g'`"
       echo "WARNING: ${repo} exited abnormally (${exit_code})" > ${status_output}
       ec=1
     fi
   done
 fi
 exit ${ec}
	#!/bin/sh
	#
	# Copyright (c) 2009, 2014, Oracle and/or its affiliates. All rights reserved.
	# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	#
	# This code is free software; you can redistribute it and/or modify it
	# under the terms of the GNU General Public License version 2 only, as
	# published by the Free Software Foundation.
	#
	# This code 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
	# version 2 for more details (a copy is included in the LICENSE file that
	# accompanied this code).
	#
	# You should have received a copy of the GNU General Public License version
	# 2 along with this work; if not, write to the Free Software Foundation,
	# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	#
	# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	# or visit www.oracle.com if you need additional information or have any
	# questions.
	#

	# Shell script for a fast parallel forest/trees command

	usage() {
	echo "usage: $0 [-h\|--help] [-q\|--quiet] [-v\|--verbose] [-s\|--sequential] [--] <command> [commands...]" > ${status_output}
	echo "Environment variables which modify behaviour:"
	echo " HGFOREST_QUIET : (boolean) If 'true' then standard output is redirected to /dev/null"
	echo " HGFOREST_VERBOSE : (boolean) If 'true' then Mercurial asked to produce verbose output"
	echo " HGFOREST_SEQUENTIAL : (boolean) If 'true' then repos are processed sequentially. Disables concurrency"
	echo " HGFOREST_GLOBALOPTS : (string, must begin with space) Additional Mercurial global options"
	echo " HGFOREST_REDIRECT : (file path) Redirect standard output to specified file"
	echo " HGFOREST_FIFOS : (boolean) Default behaviour for FIFO detection. Does not override FIFOs disabled"
	echo " HGFOREST_CONCURRENCY: (positive integer) Number of repos to process concurrently"
	echo " HGFOREST_DEBUG : (boolean) If 'true' then temp files are retained"
	exit 1
	}

	global_opts="${HGFOREST_GLOBALOPTS:-}"
	status_output="${HGFOREST_REDIRECT:-/dev/stdout}"
	qflag="${HGFOREST_QUIET:-false}"
	vflag="${HGFOREST_VERBOSE:-false}"
	sflag="${HGFOREST_SEQUENTIAL:-false}"
	while [ $# -gt 0 ]
	do
	case $1 in
	-h \| --help )
	usage
	;;

	-q \| --quiet )
	qflag="true"
	;;

	-v \| --verbose )
	vflag="true"
	;;

	-s \| --sequential )
	sflag="true"
	;;

	'--' ) # no more options
	shift; break
	;;

	-*) # bad option
	usage
	;;

	* ) # non option
	break
	;;
	esac
	shift
	done

	# silence standard output?
	if [ ${qflag} = "true" ] ; then
	global_opts="${global_opts} -q"
	status_output="/dev/null"
	fi

	# verbose output?
	if [ ${vflag} = "true" ] ; then
	global_opts="${global_opts} -v"
	fi

	# Make sure we have a command.
	if [ $# -lt 1 -o -z "${1:-}" ] ; then
	echo "ERROR: No command to hg supplied!"
	usage
	fi

	command="$1"; shift
	command_args="${@:-}"

	# Clean out the temporary directory that stores the pid files.
	tmp=/tmp/forest.$$
	rm -f -r ${tmp}
	mkdir -p ${tmp}


	if [ "${HGFOREST_DEBUG:-false}" = "true" ] ; then
	echo "DEBUG: temp files are in: ${tmp}"
	fi

	# Check if we can use fifos for monitoring sub-process completion.
	echo "1" > ${tmp}/read
	while_subshell=1
	while read line; do
	while_subshell=0
	break;
	done < ${tmp}/read
	rm ${tmp}/read

	on_windows=`uname -s \| egrep -ic -e 'cygwin\|msys'`

	if [ ${while_subshell} = "1" -o ${on_windows} = "1" ]; then
	# cygwin has (2014-04-18) broken (single writer only) FIFOs
	# msys has (2014-04-18) no FIFOs.
	# older shells create a sub-shell for redirect to while
	have_fifos="false"
	else
	have_fifos="${HGFOREST_FIFOS:-true}"
	fi

	safe_interrupt () {
	if [ -d ${tmp} ]; then
	if [ "`ls ${tmp}/*.pid`" != "" ]; then
	echo "Waiting for processes ( `cat ${tmp}/..pid ${tmp}/.pid 2> /dev/null \| tr '\n' ' '`) to terminate nicely!" > ${status_output}
	sleep 1
	# Pipe stderr to dev/null to silence kill, that complains when trying to kill
	# a subprocess that has already exited.
	kill -TERM `cat ${tmp}/*.pid \| tr '\n' ' '` 2> /dev/null
	wait
	echo "Interrupt complete!" > ${status_output}
	fi
	rm -f -r ${tmp}
	fi
	exit 130
	}

	nice_exit () {
	if [ -d ${tmp} ]; then
	if [ "`ls -A ${tmp} 2> /dev/null`" != "" ]; then
	wait
	fi
	if [ "${HGFOREST_DEBUG:-false}" != "true" ] ; then
	rm -f -r ${tmp}
	fi
	fi
	}

	trap 'safe_interrupt' INT QUIT
	trap 'nice_exit' EXIT

	subrepos="corba jaxp jaxws langtools jdk hotspot nashorn"
	subrepos_extra="jdk/src/closed jdk/make/closed jdk/test/closed hotspot/make/closed hotspot/src/closed hotspot/test/closed deploy install sponsors pubs"

	# Only look in specific locations for possible forests (avoids long searches)
	pull_default=""
	repos=""
	repos_extra=""
	if [ "${command}" = "clone" -o "${command}" = "fclone" -o "${command}" = "tclone" ] ; then
	# we must be a clone
	if [ ! -f .hg/hgrc ] ; then
	echo "ERROR: Need initial repository to use this script" > ${status_output}
	exit 1
	fi

	# the clone must know where it came from (have a default pull path).
	pull_default=`hg paths default`
	if [ "${pull_default}" = "" ] ; then
	echo "ERROR: Need initial clone with 'hg paths default' defined" > ${status_output}
	exit 1
	fi

	# determine which sub repos need to be cloned.
	for i in ${subrepos} ; do
	if [ ! -f ${i}/.hg/hgrc ] ; then
	repos="${repos} ${i}"
	fi
	done

	pull_default_tail=`echo ${pull_default} \| sed -e 's@^.://[^/]/\(.*\)@\1@'`

	if [ -n "${command_args}" ] ; then
	# if there is an "extra sources" path then reparent "extra" repos to that path
	if [ "x${pull_default}" = "x${pull_default_tail}" ] ; then
	echo "ERROR: Need initial clone from non-local source" > ${status_output}
	exit 1
	fi
	pull_extra="${command_args}/${pull_default_tail}"

	# determine which extra subrepos need to be cloned.
	for i in ${subrepos_extra} ; do
	if [ ! -f ${i}/.hg/hgrc ] ; then
	repos_extra="${repos_extra} ${i}"
	fi
	done
	else
	if [ "x${pull_default}" = "x${pull_default_tail}" ] ; then
	# local source repo. Clone the "extra" subrepos that exist there.
	for i in ${subrepos_extra} ; do
	if [ -f ${pull_default}/${i}/.hg/hgrc -a ! -f ${i}/.hg/hgrc ] ; then
	# sub-repo there in source but not here
	repos_extra="${repos_extra} ${i}"
	fi
	done
	fi
	fi

	# Any repos to deal with?
	if [ "${repos}" = "" -a "${repos_extra}" = "" ] ; then
	echo "No repositories to process." > ${status_output}
	exit
	fi

	# Repos to process concurrently. Clone does better with low concurrency.
	at_a_time="${HGFOREST_CONCURRENCY:-2}"
	else
	# Process command for all of the present repos
	for i in . ${subrepos} ${subrepos_extra} ; do
	if [ -d ${i}/.hg ] ; then
	repos="${repos} ${i}"
	fi
	done

	# Any repos to deal with?
	if [ "${repos}" = "" ] ; then
	echo "No repositories to process." > ${status_output}
	exit
	fi

	# any of the repos locked?
	locked=""
	for i in ${repos} ; do
	if [ -h ${i}/.hg/store/lock -o -f ${i}/.hg/store/lock ] ; then
	locked="${i} ${locked}"
	fi
	done
	if [ "${locked}" != "" ] ; then
	echo "ERROR: These repositories are locked: ${locked}" > ${status_output}
	exit 1
	fi

	# Repos to process concurrently.
	at_a_time="${HGFOREST_CONCURRENCY:-8}"
	fi

	# Echo out what repositories we do a command on.
	echo "# Repositories: ${repos} ${repos_extra}" > ${status_output}

	if [ "${command}" = "serve" ] ; then
	# "serve" is run for all the repos as one command.
	(
	(
	cwd=`pwd`
	serving=`basename ${cwd}`
	(
	echo "[web]"
	echo "description = ${serving}"
	echo "allow_push = *"
	echo "push_ssl = False"

	echo "[paths]"
	for i in ${repos} ; do
	if [ "${i}" != "." ] ; then
	echo "/${serving}/${i} = ${i}"
	else
	echo "/${serving} = ${cwd}"
	fi
	done
	) > ${tmp}/serve.web-conf

	echo "serving root repo ${serving}" > ${status_output}

	echo "hg${global_opts} serve" > ${status_output}
	(PYTHONUNBUFFERED=true hg${global_opts} serve -A ${status_output} -E ${status_output} --pid-file ${tmp}/serve.pid --web-conf ${tmp}/serve.web-conf; echo "$?" > ${tmp}/serve.pid.rc ) 2>&1 &
	) 2>&1 \| sed -e "s@^@serve: @" > ${status_output}
	) &
	else
	# Run the supplied command on all repos in parallel.

	# n is the number of subprocess started or which might still be running.
	n=0
	if [ ${have_fifos} = "true" ]; then
	# if we have fifos use them to detect command completion.
	mkfifo ${tmp}/fifo
	exec 3<>${tmp}/fifo
	fi

	# iterate over all of the subrepos.
	for i in ${repos} ${repos_extra} ; do
	n=`expr ${n} '+' 1`
	repopidfile=`echo ${i} \| sed -e 's@./@@' -e 's@/@_@g'`
	reponame=`echo ${i} \| sed -e :a -e 's/^.\{1,20\}$/ &/;ta'`
	pull_base="${pull_default}"

	# regular repo or "extra" repo?
	for j in ${repos_extra} ; do
	if [ "${i}" = "${j}" ] ; then
	# it's an "extra"
	pull_base="${pull_extra}"
	fi
	done

	# remove trailing slash
	pull_base="`echo ${pull_base} \| sed -e 's@[/]*$@@'`"

	# execute the command on the subrepo
	(
	(
	if [ "${command}" = "clone" -o "${command}" = "fclone" -o "${command}" = "tclone" ] ; then
	# some form of clone
	clone_newrepo="${pull_base}/${i}"
	parent_path="`dirname ${i}`"
	if [ "${parent_path}" != "." ] ; then
	times=0
	while [ ! -d "${parent_path}" ] ; do ## nested repo, ensure containing dir exists
	if [ "${sflag}" = "true" ] ; then
	# Missing parent is fatal during sequential operation.
	echo "ERROR: Missing parent path: ${parent_path}" > ${status_output}
	exit 1
	fi
	times=`expr ${times} '+' 1`
	if [ `expr ${times} '%' 10` -eq 0 ] ; then
	echo "${parent_path} still not created, waiting..." > ${status_output}
	fi
	sleep 5
	done
	fi
	# run the clone command.
	echo "hg${global_opts} clone ${clone_newrepo} ${i}" > ${status_output}
	(PYTHONUNBUFFERED=true hg${global_opts} clone ${clone_newrepo} ${i}; echo "$?" > ${tmp}/${repopidfile}.pid.rc ) 2>&1 &
	else
	# run the command.
	echo "cd ${i} && hg${global_opts} ${command} ${command_args}" > ${status_output}
	cd ${i} && (PYTHONUNBUFFERED=true hg${global_opts} ${command} ${command_args}; echo "$?" > ${tmp}/${repopidfile}.pid.rc ) 2>&1 &
	fi

	echo $! > ${tmp}/${repopidfile}.pid
	) 2>&1 \| sed -e "s@^@${reponame}: @" > ${status_output}
	# tell the fifo waiter that this subprocess is done.
	if [ ${have_fifos} = "true" ]; then
	echo "${i}" >&3
	fi
	) &

	if [ "${sflag}" = "true" ] ; then
	# complete this task before starting another.
	wait
	else
	if [ "${have_fifos}" = "true" ]; then
	# check on count of running subprocesses and possibly wait for completion
	if [ ${n} -ge ${at_a_time} ] ; then
	# read will block until there are completed subprocesses
	while read repo_done; do
	n=`expr ${n} '-' 1`
	if [ ${n} -lt ${at_a_time} ] ; then
	# we should start more subprocesses
	break;
	fi
	done <&3
	fi
	else
	# Compare completions to starts
	completed="`(ls -a1 ${tmp}/*.pid.rc 2> /dev/null \| wc -l) \|\| echo 0`"
	while [ `expr ${n} '-' ${completed}` -ge ${at_a_time} ] ; do
	# sleep a short time to give time for something to complete
	sleep 1
	completed="`(ls -a1 ${tmp}/*.pid.rc 2> /dev/null \| wc -l) \|\| echo 0`"
	done
	fi
	fi
	done
	fi

	# Wait for all subprocesses to complete
	wait

	# Terminate with exit 0 only if all subprocesses were successful
	ec=0
	if [ -d ${tmp} ]; then
	rcfiles="`(ls -a ${tmp}/*.pid.rc 2> /dev/null) \|\| echo ''`"
	for rc in ${rcfiles} ; do
	exit_code=`cat ${rc} \| tr -d ' \n\r'`
	if [ "${exit_code}" != "0" ] ; then
	repo="`echo ${rc} \| sed -e 's@^'${tmp}'@@' -e 's@/\([^/]\)\.pid\.rc$@\1@' -e 's@_@/@g'`"
	echo "WARNING: ${repo} exited abnormally (${exit_code})" > ${status_output}
	ec=1
	fi
	done
	fi
	exit ${ec}