[dpdk-dev] [PATCH v2] build: add definitions for use as meson subproject

[Stephen Hemminger <stephen@networkplumber.org>]

Some other projects using meson may not be able to use DPDK
using the standard distribution pkg-config mechanism.
Meson supports a way to handle this via the subproject
  https://mesonbuild.com/Subprojects.html

This patch adds the necessary dependency to follow the
"Naming convention for dependency variables" from the documentation.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

v2 - add link libraries

 lib/meson.build |  5 +++++
 meson.build     | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/lib/meson.build b/lib/meson.build
index 499d26060fdd..e6df538bd6ef 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -241,6 +241,11 @@ foreach l:libraries
 
     dpdk_libraries = [shared_lib] + dpdk_libraries
     dpdk_static_libraries = [static_lib] + dpdk_static_libraries
+    if get_option('default_library') == 'static'
+        dpdk_libs_deps += static_dep
+    else
+        dpdk_libs_deps += shared_dep
+    endif
 
     set_variable('shared_rte_' + name, shared_dep)
     set_variable('static_rte_' + name, static_dep)
diff --git a/meson.build b/meson.build
index 12cb6e0e83f3..3bf6bb794ce1 100644
--- a/meson.build
+++ b/meson.build
@@ -36,6 +36,7 @@ dpdk_drivers = []
 dpdk_extra_ldflags = []
 dpdk_libs_disabled = []
 dpdk_drvs_disabled = []
+dpdk_libs_deps = []
 abi_version_file = files('ABI_VERSION')
 
 if host_machine.cpu_family().startswith('x86')
@@ -97,6 +98,18 @@ configure_file(output: build_cfg,
 # build pkg-config files for dpdk
 subdir('buildtools/pkg-config')
 
+# If DPDK is being built as subproject then define
+# variable with the dependency convention
+if meson.is_subproject()
+    libdpdk_dep = declare_dependency(
+        version: meson.project_version(),
+        compile_args : pkg_extra_cflags,
+        dependencies: dpdk_libs_deps,
+        link_args: dpdk_extra_ldflags,
+        link_with: dpdk_libraries
+    )
+endif
+
 # final output, list all the libs and drivers to be built
 # this does not affect any part of the build, for information only.
 output_message = '\n=================\nLibraries Enabled\n=================\n'
-- 
2.30.2