From: Helmut Grohne <helmut@subdivi.de>
Date: Tue, 6 Aug 2019 16:16:05 +0200
Subject: make cross-compilation possible

---
 Makefile | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/Makefile b/Makefile
index 3b8f0d9..5154bff 100644
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,10 @@ BZERO          ?=
 MUSL           ?= 0
 BUNDLED_LIBBSD ?= 0
 PLEDGE         ?= noop
+PKG_CONFIG     ?= pkg-config
+WGET           ?= wget
+libbsd_VERSION ?= 0.10.0
+libbsd_BASEURL ?= http://libbsd.freedesktop.org/releases/
 #                                                                #
 ##################################################################
 
@@ -93,13 +97,13 @@ LIBBSD_LDFLAGS :=
 else
 
 LIBBSD_PKG_VERSION := 0.8
-LIBBSD_PKG_CHECK   := $(shell pkg-config libbsd --atleast-version=$(LIBBSD_PKG_VERSION) && echo ok)
+LIBBSD_PKG_CHECK   := $(shell $(PKG_CONFIG) libbsd --atleast-version=$(LIBBSD_PKG_VERSION) && echo ok)
 ifneq ($(strip $(LIBBSD_PKG_CHECK)),ok)
   $(error libbsd is not installed or version is older than $(LIBBSD_PKG_VERSION))
 endif
 LIBBSD_DEPS    :=
-LIBBSD_CFLAGS  := $(shell pkg-config libbsd-overlay --cflags)
-LIBBSD_LDFLAGS := $(shell pkg-config libbsd-overlay --libs)
+LIBBSD_CFLAGS  := $(shell $(PKG_CONFIG) libbsd-overlay --cflags)
+LIBBSD_LDFLAGS := $(shell $(PKG_CONFIG) libbsd-overlay --libs)
 
 endif
 
@@ -108,8 +112,8 @@ endif
 # Git submodule corresponding to libwaive is properly checked out.
 #
 ifeq ($(PLEDGE),waive)
-SECCOMP_CFLAGS := $(shell pkg-config libseccomp --cflags)
-SECCOMP_LIBS   := $(shell pkg-config libseccomp --libs)
+SECCOMP_CFLAGS := $(shell $(PKG_CONFIG) libseccomp --cflags)
+SECCOMP_LIBS   := $(shell $(PKG_CONFIG) libseccomp --libs)
 CFLAGS  += $(SECCOMP_CFLAGS) -pthread
 LDFLAGS += $(SECCOMP_LIBS) -pthread
 S       += libwaive/waive.c