add examples for dynamic linking / loading

one example by doing it manually with an ugly Makefile,
another one by using autotools.

Signed-off-by: Manuel Traut <manut@linutronix.de>

1 files changed, 33 insertions, 0 deletions

diff --git a/schulung_tools/linking/hello/Makefile b/schulung_tools/linking/hello/Makefile
new file mode 100644
index 0000000..a5b4c26
--- /dev/null
+++ b/schulung_tools/linking/hello/Makefile
@@ -0,0 +1,33 @@
+hello: hello.c libfunc.so
+	$(CROSS_COMPILE)gcc -g -ohello hello.c -L. -lfunc
+
+hello2: hello.c libfunc.a
+	rm -f libfunc.so
+	$(CROSS_COMPILE)gcc -g -ohello2 hello.c -L. -lfunc
+
+libfunc.so: libfunc.so.0.0.1
+	ln -s libfunc.so.0.0.1 libfunc.so
+
+libfunc.so.0.0.1: func1.o func2.o
+	$(CROSS_COMPILE)gcc -shared -olibfunc.so.0.0.1 -Wl,-soname,libfunc.so.0 func1.o func2.o
+
+libfunc.a: func1.o func2.o
+	$(CROSS_COMPILE)ar cr libfunc.a func1.o func2.o
+	$(CROSS_COMPILE)ranlib libfunc.a
+
+func1.o: func1.c
+	$(CROSS_COMPILE)gcc -fPIC -g -c func1.c
+
+func2.o: func2.c
+	$(CROSS_COMPILE)gcc -fPIC -g -c func2.c
+
+install_lib: libfunc.so.0.0.1
+	echo "/opt/acme/lib" > /etc/ld.so.conf.d/acme.conf
+	mkdir -p /opt/acme/lib
+	cp libfunc.so.0.0.1 /opt/acme/lib
+	ldconfig
+
+clean:
+	rm -f hello hello2 *.o lib*
+
+.PHONY: clean