libs_list :=
# Build a library with symbolic name $(1). The library is defined by
# various variables prefixed by ‘$(1)_’:
#
# - $(1)_NAME: the name of the library (e.g. ‘libfoo’); defaults to
# $(1).
#
# - $(1)_DIR: the directory containing the sources of the library, and
# where the (non-installed) library will be placed.
#
# - $(1)_SOURCES: the source files of the library.
#
# - $(1)_LIBS: the symbolic names of other libraries on which this
# library depends.
#
# - $(1)_ALLOW_UNDEFINED: if set, the library is allowed to have
# undefined symbols. Has no effect for static libraries.
#
# - $(1)_LDFLAGS: additional linker flags.
#
# - $(1)_LDFLAGS_PROPAGATED: additional linker flags, also propagated
# to the linking of programs/libraries that use this library.
#
# - BUILD_SHARED_LIBS: if equal to ‘1’, a dynamic library will be
# built, otherwise a static library.
#
# - libdir: the directory where the library will be installed (if
# required).
define build-library =
$(1)_NAME ?= $(1)
_d := $$(strip $$($(1)_DIR))
_srcs := $$(foreach src, $$($(1)_SOURCES), $$(_d)/$$(src))
$(1)_OBJS := $$(addsuffix .o, $$(basename $$(_srcs)))
_libs := $$(foreach lib, $$($(1)_LIBS), $$($$(lib)_PATH))
$(1)_LDFLAGS_USE :=
$(1)_LDFLAGS_USE_INSTALLED :=
ifeq ($(BUILD_SHARED_LIBS), 1)
ifndef $(1)_ALLOW_UNDEFINED
$(1)_LDFLAGS += -z defs
endif
$(1)_PATH := $$(_d)/$$($(1)_NAME).so
$$($(1)_PATH): $$($(1)_OBJS) $$(_libs)
$(QUIET) $(CXX) -o $$@ -shared $(GLOBAL_LDFLAGS) $$($(1)_OBJS) $$($(1)_LDFLAGS) $$($(1)_LDFLAGS_PROPAGATED) $$(foreach lib, $$($(1)_LIBS), $$($$(lib)_LDFLAGS_USE))
$(1)_LDFLAGS_USE += -L$$(_d) -Wl,-rpath,$$(abspath $$(_d)) -l$$(patsubst lib%,%,$$(strip $$($(1)_NAME)))
$(1)_INSTALL_DIR := $$(libdir)
$(1)_INSTALL_PATH := $$($(1)_INSTALL_DIR)/$$($(1)_NAME).so
_libs_final := $$(foreach lib, $$($(1)_LIBS), $$($$(lib)_INSTALL_PATH))
$$($(1)_INSTALL_PATH): $$($(1)_OBJS) $$(_libs_final)
install -d $$($(1)_INSTALL_DIR)
$(QUIET) $(CXX) -o $$@ -shared $(GLOBAL_LDFLAGS) $$($(1)_OBJS) $$($(1)_LDFLAGS) $$($(1)_LDFLAGS_PROPAGATED) $$(foreach lib, $$($(1)_LIBS), $$($$(lib)_LDFLAGS_USE_INSTALLED))
$(1)_LDFLAGS_USE_INSTALLED += -L$$($(1)_INSTALL_DIR) -Wl,-rpath,$$($(1)_INSTALL_DIR) -l$$(patsubst lib%,%,$$(strip $$($(1)_NAME)))
else
$(1)_PATH := $$(_d)/$$($(1)_NAME).a
$$($(1)_PATH): $$($(1)_OBJS)
$(QUIET) ar crs $$@ $$?
$(1)_LDFLAGS_USE += $$($(1)_PATH) $$($(1)_LDFLAGS)
$(1)_INSTALL_PATH := $$(libdir)/$$($(1)_NAME).a
endif
$(1)_LDFLAGS_USE += $$($(1)_LDFLAGS_PROPAGATED)
$(1)_LDFLAGS_USE_INSTALLED += $$($(1)_LDFLAGS_PROPAGATED)
# Propagate CXXFLAGS to the individual object files.
$$(foreach obj, $$($(1)_OBJS), $$(eval $$(obj)_CXXFLAGS=$$($(1)_CXXFLAGS)))
include $$(wildcard $$(_d)/*.dep)
libs_list += $$($(1)_PATH)
clean_files += $$(_d)/*.a $$(_d)/*.so $$(_d)/*.o $$(_d)/*.dep
dist_files += $$(_srcs)
endef