Auto: mirroring installation structure in build tree.

This makes the build tree more organized, which is good for adding new
stuff.  Now, it's useful for example for adding manual pages in man3/,
but it may be useful in the future for example for extending the build
system to run linters (e.g., clang-tidy(1), Clang analyzer, ...) on the
C source code.

Previously, the build tree was quite flat, and looked like this (after
`./configure && make`):

    $ tree -I src build
    build
    ├── Makefile
    ├── autoconf.data
    ├── autoconf.err
    ├── echo
    ├── libnxt.a
    ├── nxt_auto_config.h
    ├── nxt_version.h
    ├── unitd
    └── unitd.8

    1 directory, 9 files

And after this patch, it looks like this:

    $ tree -I src build
    build
    ├── Makefile
    ├── autoconf.data
    ├── autoconf.err
    ├── bin
    │   └── echo
    ├── include
    │   ├── nxt_auto_config.h
    │   └── nxt_version.h
    ├── lib
    │   ├── libnxt.a
    │   └── unit
    │       └── modules
    ├── sbin
    │   └── unitd
    ├── share
    │   └── man
    │       └── man8
    │           └── unitd.8
    └── var
        ├── lib
        │   └── unit
        ├── log
        │   └── unit
        └── run
            └── unit

    17 directories, 9 files

It also solves one issue introduced in
5a37171f733f ("Added default values for pathnames.").  Before that
commit, it was possible to run unitd from the build system
(`./build/unitd`).  Now, since it expects files in a very specific
location, that has been broken.  By having a directory structure that
mirrors the installation, it's possible to trick it to believe it's
installed, and run it from there:

    $ ./configure --prefix=./build
    $ make
    $ ./build/sbin/unitd

Fixes: 5a37171f733f ("Added default values for pathnames.")
Reported-by: Liam Crilly <liam@nginx.com>
Reviewed-by: Konstantin Pavlov <thresh@nginx.com>
Reviewed-by: Andrew Clayton <a.clayton@nginx.com>
Cc: Andrei Zeliankou <zelenkov@nginx.com>
Cc: Zhidao Hong <z.hong@f5.com>
Signed-off-by: Alejandro Colomar <alx@nginx.com>

3 files changed, 9 insertions, 9 deletions

diff --git a/pkg/deb/Makefile b/pkg/deb/Makefile
index 788bbe5a..fc631c6d 100644
--- a/pkg/deb/Makefile
+++ b/pkg/deb/Makefile
@@ -288,8 +288,8 @@ test: unit modules
 	for so in `find debuild-*/unit-$(VERSION)/debian/build-unit/ -type f \( -name "*.so" -o -name "*.jar" \)`; do \
 		soname=`basename $${so}` ; \
 		test "$${soname}" = "java.unit.so" && continue ; \
-		test -h debuild/unit-$(VERSION)/debian/build-unit/build/$${soname} || \
-		ln -fs `pwd`/$${so} debuild/unit-$(VERSION)/debian/build-unit/build/$${soname} ; \
+		test -h debuild/unit-$(VERSION)/debian/build-unit/build/lib/$${soname} || \
+		ln -fs `pwd`/$${so} debuild/unit-$(VERSION)/debian/build-unit/build/lib/$${soname} ; \
 	done ; \
 	( cd debuild/unit-$(VERSION)/debian/build-unit && env python3 -m pytest --user=nobody $(PYTEST_ARGS) ) ; \
 	}
@@ -299,8 +299,8 @@ test-debug: unit modules
 	for so in `find debuild-*/unit-$(VERSION)/debian/build-unit-debug/ -type f \( -name "*.so" -o -name "*.jar" \)`; do \
 		soname=`basename $${so}` ; \
 		test "$${soname}" = "java.unit.so" && continue ; \
-		test -h debuild/unit-$(VERSION)/debian/build-unit-debug/build/$${soname} || \
-		ln -fs `pwd`/$${so} debuild/unit-$(VERSION)/debian/build-unit-debug/build/$${soname} ; \
+		test -h debuild/unit-$(VERSION)/debian/build-unit-debug/build/lib/$${soname} || \
+		ln -fs `pwd`/$${so} debuild/unit-$(VERSION)/debian/build-unit-debug/build/lib/$${soname} ; \
 	done ; \
 	( cd debuild/unit-$(VERSION)/debian/build-unit-debug && env python3 -m pytest --user=nobody $(PYTEST_ARGS) ) ; \
 	}
diff --git a/pkg/deb/debian/rules.in b/pkg/deb/debian/rules.in
index 0fe34b72..01604e86 100644
--- a/pkg/deb/debian/rules.in
+++ b/pkg/deb/debian/rules.in
@@ -69,7 +69,7 @@ configure.unit_debug: config.env.unit_debug
 build-arch.%: configure.%
 	dh_testdir
 	$(MAKE) -C $(BUILDDIR_$*)
-	$(MAKE) -C $(BUILDDIR_$*) build/libunit.a
+	$(MAKE) -C $(BUILDDIR_$*) build/lib/libunit.a
 ifeq ($(DOTESTS), 1)
 	$(MAKE) -C $(BUILDDIR_$*) tests
 endif
@@ -112,8 +112,8 @@ install: build do.tests
 	dh_installlogrotate
 	cd $(BUILDDIR_unit) && DESTDIR=$(INSTALLDIR) make install
 	cd $(BUILDDIR_unit) && DESTDIR=$(INSTALLDIR_dev) make libunit-install
-	install -m 755 $(BUILDDIR_unit_debug)/build/unitd $(INSTALLDIR)/usr/sbin/unitd-debug
-	install -m 644 $(BUILDDIR_unit_debug)/build/libunit.a $(INSTALLDIR_dev)/usr/lib/$(DEB_HOST_MULTIARCH)/libunit-debug.a
+	install -m 755 $(BUILDDIR_unit_debug)/build/sbin/unitd $(INSTALLDIR)/usr/sbin/unitd-debug
+	install -m 644 $(BUILDDIR_unit_debug)/build/lib/libunit.a $(INSTALLDIR_dev)/usr/lib/$(DEB_HOST_MULTIARCH)/libunit-debug.a
 	mkdir -p $(INSTALLDIR)/usr/share/doc/unit/examples
 	install -m 644 debian/unit.example.config $(INSTALLDIR)/usr/share/doc/unit/examples/example.config
 	install -m 644 CHANGES $(INSTALLDIR)/usr/share/doc/unit/changelog
diff --git a/pkg/docker/template.Dockerfile b/pkg/docker/template.Dockerfile
index ea3224cc..b655ca73 100644
--- a/pkg/docker/template.Dockerfile
+++ b/pkg/docker/template.Dockerfile
@@ -26,11 +26,11 @@ RUN set -ex \
                 --libdir=/usr/lib/$DEB_HOST_MULTIARCH" \
     && ./configure $CONFIGURE_ARGS --cc-opt="$CC_OPT" --ld-opt="$LD_OPT" --modulesdir=/usr/lib/unit/debug-modules --debug \
     && make -j $NCPU unitd \
-    && install -pm755 build/unitd /usr/sbin/unitd-debug \
+    && install -pm755 build/sbin/unitd /usr/sbin/unitd-debug \
     && make clean \
     && ./configure $CONFIGURE_ARGS --cc-opt="$CC_OPT" --ld-opt="$LD_OPT" --modulesdir=/usr/lib/unit/modules \
     && make -j $NCPU unitd \
-    && install -pm755 build/unitd /usr/sbin/unitd \
+    && install -pm755 build/sbin/unitd /usr/sbin/unitd \
     && make clean \
     && ./configure $CONFIGURE_ARGS --cc-opt="$CC_OPT" --modulesdir=/usr/lib/unit/debug-modules --debug \
     && ./configure @@CONFIGURE@@ \