[RFC 5/6] build: install indirect headers to a dedicated directory

[David Marchand <david.marchand@redhat.com>]

The headers check currently skips "indirect" headers as instrusted via
the indirect_headers meson variable.

This headers check has some limitation that will be addressed in a next
change by inspected all exported headers.
However, exported headers lack the information about "indirect" quality.

Separate "indirect" headers by exporting them in a internal/ sub directory.
This also makes it more obvious which headers are not to be directly used
by an application.

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 buildtools/pkg-config/meson.build | 8 +++++++-
 lib/eal/x86/include/meson.build   | 3 ++-
 lib/meson.build                   | 2 +-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/buildtools/pkg-config/meson.build b/buildtools/pkg-config/meson.build
index b36add17e3..809706fe3e 100644
--- a/buildtools/pkg-config/meson.build
+++ b/buildtools/pkg-config/meson.build
@@ -27,12 +27,18 @@ endif
 # are skipped in the case of static linkage thanks to the flag --as-needed.
 
 
+subdirs = [ '.', 'internal' ]
+if get_option('include_subdir_arch') != ''
+    subdirs = [ subdirs, get_option('include_subdir_arch') ]
+    subdirs = [ subdirs, join_paths(get_option('include_subdir_arch'), 'internal')]
+endif
+
 pkg.generate(name: 'dpdk-libs',
         filebase: 'libdpdk-libs',
         description: '''Internal-only DPDK pkgconfig file. Not for direct use.
 Use libdpdk.pc instead of this file to query DPDK compile/link arguments''',
         version: meson.project_version(),
-        subdirs: [get_option('include_subdir_arch'), '.'],
+        subdirs: subdirs,
         extra_cflags: pkg_extra_cflags,
         libraries: ['-Wl,--as-needed'] + dpdk_libraries,
         libraries_private: dpdk_extra_ldflags)
diff --git a/lib/eal/x86/include/meson.build b/lib/eal/x86/include/meson.build
index 52d2f8e969..a100330208 100644
--- a/lib/eal/x86/include/meson.build
+++ b/lib/eal/x86/include/meson.build
@@ -22,5 +22,6 @@ arch_indirect_headers = files(
         'rte_byteorder_32.h',
         'rte_byteorder_64.h',
 )
-install_headers(arch_headers + arch_indirect_headers, subdir: get_option('include_subdir_arch'))
+install_headers(arch_headers, subdir: get_option('include_subdir_arch'))
+install_headers(arch_indirect_headers, subdir: join_paths(get_option('include_subdir_arch'), 'internal'))
 dpdk_chkinc_headers += arch_headers
diff --git a/lib/meson.build b/lib/meson.build
index ce92cb5537..78ada7782e 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -202,7 +202,7 @@ foreach l:libraries
     dpdk_libs_enabled += name
     dpdk_conf.set('RTE_LIB_' + name.to_upper(), 1)
     install_headers(headers)
-    install_headers(indirect_headers)
+    install_headers(indirect_headers, subdir: 'internal')
     if get_option('enable_driver_sdk')
         install_headers(driver_sdk_headers)
     endif
-- 
2.47.0