GNUMakefile: install libstdbuf (#8238)

Use external libstdbuf.so when building with make, as embedding the library
is only needed to work around "cargo install" limitations with shared libraries.

Also change default installation directory to /usr/local/libexec/coreutils/ for consistency
with GNU coreutils

Signed-off-by: Etienne Cordonnier <ecordonnier@snap.com>

Author: sylvestre

.cargo/config.toml

@@ -4,7 +4,7 @@ linker = "x86_64-unknown-redox-gcc"
 [env]
 PROJECT_NAME_FOR_VERSION_STRING = "uutils coreutils"
 # See feat_external_libstdbuf in src/uu/stdbuf/Cargo.toml
-LIBSTDBUF_DIR = "/usr/lib"
+LIBSTDBUF_DIR = "/usr/local/libexec/coreutils"
 
 # libstdbuf must be a shared library, so musl libc can't be linked statically
 # https://github.com/rust-lang/rust/issues/82193

GNUmakefile

@@ -33,6 +33,9 @@ PREFIX ?= /usr/local
 DESTDIR ?=
 BINDIR ?= $(PREFIX)/bin
 DATAROOTDIR ?= $(PREFIX)/share
+LIBSTDBUF_DIR ?= $(PREFIX)/libexec/coreutils
+# Export variable so that it is used during the build
+export LIBSTDBUF_DIR
 
 INSTALLDIR_BIN=$(DESTDIR)$(BINDIR)
 
@@ -199,6 +202,8 @@ ifneq ($(OS),Windows_NT)
 	PROGS := $(PROGS) $(UNIX_PROGS)
 # Build the selinux command even if not on the system
 	PROGS := $(PROGS) $(SELINUX_PROGS)
+# Always use external libstdbuf when building with make (Unix only)
+	CARGOFLAGS += --features feat_external_libstdbuf
 endif
 
 UTILS ?= $(PROGS)
@@ -438,6 +443,10 @@ endif
 
 install: build install-manpages install-completions install-locales
 	mkdir -p $(INSTALLDIR_BIN)
+ifneq ($(OS),Windows_NT)
+	mkdir -p $(DESTDIR)$(LIBSTDBUF_DIR)
+	$(INSTALL) -m 755 $(BUILDDIR)/deps/libstdbuf* $(DESTDIR)$(LIBSTDBUF_DIR)/
+endif
 ifeq (${MULTICALL}, y)
 	$(INSTALL) $(BUILDDIR)/coreutils $(INSTALLDIR_BIN)/$(PROG_PREFIX)coreutils
 	$(foreach prog, $(filter-out coreutils, $(INSTALLEES)), \
@@ -452,6 +461,10 @@ else
 endif
 
 uninstall:
+ifneq ($(OS),Windows_NT)
+	rm -f $(DESTDIR)$(LIBSTDBUF_DIR)/libstdbuf*
+	-rmdir $(DESTDIR)$(LIBSTDBUF_DIR) 2>/dev/null || true
+endif
 ifeq (${MULTICALL}, y)
 	rm -f $(addprefix $(INSTALLDIR_BIN)/,$(PROG_PREFIX)coreutils)
 endif