From 433b444f0aa7829663465c5dd59fb02880694e9d Mon Sep 17 00:00:00 2001
From: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Fri, 21 Feb 2020 11:25:21 +0900
Subject: [PATCH 1/3] Revert "build: Use flock to serialize ar steps as
 workaround"

This reverts commit 6707bfae86aff8a3bae74f6bbafaca54d1315480.
---
 .gitignore     | 1 -
 Application.mk | 4 ++--
 Make.defs      | 6 +-----
 Makefile       | 5 ++---
 4 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/.gitignore b/.gitignore
index 668630512c9..722303bd5ca 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,3 @@
-.arlock
 .depend
 Make.dep
 *.o
diff --git a/Application.mk b/Application.mk
index 641e89b85e2..25af1926e42 100644
--- a/Application.mk
+++ b/Application.mk
@@ -130,9 +130,9 @@ $(CXXOBJS): %$(SUFFIX)$(OBJEXT): %$(CXXEXT)
 
 .built: $(OBJS)
 ifeq ($(WINTOOL),y)
-	$(call ARLOCK, "${shell cygpath -w $(BIN)}", $(OBJS))
+	$(call ARCHIVE, "${shell cygpath -w $(BIN)}", $(OBJS))
 else
-	$(call ARLOCK, $(BIN), $(OBJS))
+	$(call ARCHIVE, $(BIN), $(OBJS))
 endif
 	$(Q) touch $@
 
diff --git a/Make.defs b/Make.defs
index 89a649b39c0..77b0c82751b 100644
--- a/Make.defs
+++ b/Make.defs
@@ -52,7 +52,7 @@ CLEANDIRS := $(dir $(wildcard $(APPDIR)$(DELIM)*$(DELIM)Makefile))
 CONFIGURED_APPS :=
 
 define Add_Application
-	include $(1)Make.defs
+  include $(1)Make.defs
 endef
 
 $(foreach BDIR, $(BUILDIRS), $(eval $(call Add_Application,$(BDIR))))
@@ -99,10 +99,6 @@ define REGISTER
 endef
 endif
 
-define ARLOCK
-	$(Q) flock .arlock $(call ARCHIVE, $1, $(2))
-endef
-
 # Tools
 
 ifeq ($(DIRLINK),)
diff --git a/Makefile b/Makefile
index dfb9da882df..e0ad31f1cfb 100644
--- a/Makefile
+++ b/Makefile
@@ -117,9 +117,9 @@ $(SYMTABOBJ): %$(OBJEXT): %.c
 
 $(BIN): $(SYMTABOBJ)
 ifeq ($(WINTOOL),y)
-	$(call ARLOCK, "${shell cygpath -w $(BIN)}", $^)
+	$(call ARCHIVE, "${shell cygpath -w $(BIN)}", $^)
 else
-	$(call ARLOCK, $(BIN), $^)
+	$(call ARCHIVE, $(BIN), $^)
 endif
 
 endif # !CONFIG_BUILD_LOADABLE
@@ -198,7 +198,6 @@ else
 		fi; \
 	)
 endif
-	$(call DELFILE, .arlock)
 	$(call DELFILE, .depend)
 	$(call DELFILE, $(SYMTABSRC))
 	$(call DELFILE, $(SYMTABOBJ))

From ee4aad7f90c2746e18dfcc29ebcd65eb8a76ae54 Mon Sep 17 00:00:00 2001
From: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Fri, 21 Feb 2020 11:28:51 +0900
Subject: [PATCH 2/3] Use flock to serialize AR

---
 .gitignore | 1 +
 Make.defs  | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/.gitignore b/.gitignore
index 722303bd5ca..7ff6bb2f442 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,7 @@ cscope.out
 /Kconfig
 /bin
 /external
+/.arlock
 /.context
 /.config
 /.depend
diff --git a/Make.defs b/Make.defs
index 77b0c82751b..805d6af1907 100644
--- a/Make.defs
+++ b/Make.defs
@@ -99,6 +99,9 @@ define REGISTER
 endef
 endif
 
+# Workaround for concurrent execution to the same library (libapps)
+AR := flock $(APPDIR)/.arlock $(AR)
+
 # Tools
 
 ifeq ($(DIRLINK),)

From 218c7a9d64e0673fccc248cb8611f3f4ec70971e Mon Sep 17 00:00:00 2001
From: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Fri, 21 Feb 2020 11:30:20 +0900
Subject: [PATCH 3/3] Use shlock instead of flock on macOS

Because macOS doesn't have flock.
---
 Make.defs      |  5 +++++
 tools/flock.sh | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100755 tools/flock.sh

diff --git a/Make.defs b/Make.defs
index 805d6af1907..3d58155d4be 100644
--- a/Make.defs
+++ b/Make.defs
@@ -100,7 +100,12 @@ endef
 endif
 
 # Workaround for concurrent execution to the same library (libapps)
+ifeq ($(CONFIG_HOST_MACOS),y)
+# macOS doesn't have flock. Use shlock instead.
+AR := $(APPDIR)/tools/flock.sh $(APPDIR)/.arlock $(AR)
+else
 AR := flock $(APPDIR)/.arlock $(AR)
+endif
 
 # Tools
 
diff --git a/tools/flock.sh b/tools/flock.sh
new file mode 100755
index 00000000000..e20c1050cfd
--- /dev/null
+++ b/tools/flock.sh
@@ -0,0 +1,36 @@
+#! /bin/sh
+
+# apps/tools/flock.sh
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+# This script tries to mimic flock using shlock
+#
+# NOTE: It just aims to be enough for our usage in libapps build.
+# Not intended to be a full replacement of flock.
+
+LOCKFILE=$1
+shift
+
+while ! shlock -f ${LOCKFILE} -p $$; do
+	sleep 1
+done
+
+set -e
+$@
+STATUS=$?
+rm -f ${LOCKFILE} || :
+exit ${STATUS}