limit parallel downloading and extracting for parallel building

Currently the number of parallel downloads is limited to 4 and the number
of extract jobs to 2.

Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>

3 files changed, 55 insertions, 0 deletions

diff --git a/scripts/lib/ptxd_make_get.sh b/scripts/lib/ptxd_make_get.sh
index 9b7bfd192..fe2613f11 100644
--- a/scripts/lib/ptxd_make_get.sh
+++ b/scripts/lib/ptxd_make_get.sh
@@ -51,6 +51,7 @@ ptxd_make_get_http() {
 	# remove any pending or half downloaded files
 	rm -f -- "${path}."*
 
+	ptxd_make_serialize_take
 	local temp_file="$(mktemp "${path}.XXXXXXXXXX")" || ptxd_bailout "failed to create tempfile"
 	wget \
 	    --passive-ftp \
@@ -66,8 +67,10 @@ ptxd_make_get_http() {
 		file "${temp_file}" | grep -vq " HTML " &&
 		touch -- "${temp_file}" &&
 		mv -- "${temp_file}" "${path}"
+		ptxd_make_serialize_put
 		return
 	}
+	ptxd_make_serialize_put
 
 	rm -f -- "${temp_file}"
 
diff --git a/scripts/lib/ptxd_make_serialize.sh b/scripts/lib/ptxd_make_serialize.sh
new file mode 100644
index 000000000..2515cd2a0
--- /dev/null
+++ b/scripts/lib/ptxd_make_serialize.sh
@@ -0,0 +1,50 @@
+#!/bin/bash
+#
+# Copyright (C) 2015 by Michael Olbrich <mol@pengutronix.de>
+#
+# See CREDITS for details about who has contributed to this project.
+#
+# For further information about the PTXdist project and license conditions
+# see the README file.
+#
+
+ptxd_make_serialize_take() {
+    local readptr="ptxd_make_serialize_${pkg_stage}_readfd"
+    local tmp
+    if [ -n "${!readptr}" ]; then
+	read -n 1 -u "${!readptr}" tmp
+    fi
+}
+export -f ptxd_make_serialize_take
+
+ptxd_make_serialize_put() {
+    local writeptr="ptxd_make_serialize_${pkg_stage}_writefd"
+    if [ -n "${!writeptr}" ]; then
+	echo -n '+' >&${!writeptr}
+    fi
+}
+export -f ptxd_make_serialize_put
+
+ptxd_make_serialize_setup() {
+    local name="${1}"
+    local count="${2}"
+    local fifo="${PTXDIST_TEMPDIR}/${name}-fifo"
+    local writeptr="ptxd_make_serialize_${name}_writefd"
+    local readptr="ptxd_make_serialize_${name}_readfd"
+    local writefd readfd
+
+    mkfifo "${fifo}" || return
+    echo -n "$(seq -s "+" 0 ${count} | sed 's/[^+]//g')" > "${fifo}" &
+    exec {readfd}< "${fifo}" &&
+    exec {writefd}> "${fifo}" &&
+    eval "${readptr}"="${readfd}" &&
+    eval "${writeptr}"="${writefd}" &&
+    export "${readptr}" "${writeptr}"
+}
+export -f ptxd_make_serialize_setup
+
+ptxd_make_serialize_init() {
+    ptxd_make_serialize_setup get 4 &&
+    ptxd_make_serialize_setup extract 2
+}
+ptxd_make_serialize_init
diff --git a/scripts/lib/ptxd_make_world_extract.sh b/scripts/lib/ptxd_make_world_extract.sh
index dc32f7548..955c4872b 100644
--- a/scripts/lib/ptxd_make_world_extract.sh
+++ b/scripts/lib/ptxd_make_world_extract.sh
@@ -60,6 +60,7 @@ ptxd_make_world_extract() {
 
     mkdir -p "${pkg_extract_dir}" || return
 
+    ptxd_make_serialize_take
     echo "\
 extract: pkg_src=$(ptxd_print_path ${pkg_src})
 extract: pkg_extract_dir=$(ptxd_print_path ${pkg_dir})"
@@ -83,6 +84,7 @@ extract: pkg_extract_dir=$(ptxd_print_path ${pkg_dir})"
     fi
     local ret=$?
     rm -rf "${tmpdir}"
+    ptxd_make_serialize_put
     return ${ret}
 }