build: allow using wildcards to disable drivers

Rather than having to explicitly list each and every driver to disable in a
build, we can use a small python script and the python glob library to
expand out the wildcards. This means that we can configure meson using e.g.

    meson -Ddisable_drivers=crypto/*,event/* build

to do a build omitting all the crypto and event drivers. Explicitly
specified drivers e.g. net/i40e, work as before, and can be mixed with
wildcarded drivers as required.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: Robin Jarry <robin.jarry@6wind.com>
Acked-by: Luca Boccassi <bluca@debian.org>

MAINTAINERS

@@ -130,6 +130,7 @@ F: meson_options.txt
 F: config/rte_config.h
 F: buildtools/call-sphinx-build.py
 F: buildtools/gen-pmdinfo-cfile.sh
+F: buildtools/list-dir-globs.py
 F: buildtools/map_to_def.py
 F: buildtools/symlink-drivers-solibs.sh
 

buildtools/list-dir-globs.py

@@ -0,0 +1,19 @@
+#! /usr/bin/env python3
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2020 Intel Corporation
+
+import sys
+import os
+from glob import iglob
+
+if len(sys.argv) != 2:
+    print("Usage: {0} <path-glob>[,<path-glob>[,...]]".format(sys.argv[0]))
+    sys.exit(1)
+
+root = os.path.join(os.getenv('MESON_SOURCE_ROOT', '.'),
+                    os.getenv('MESON_SUBDIR', '.'))
+
+for path in sys.argv[1].split(','):
+    for p in iglob(os.path.join(root, path)):
+        if os.path.isdir(p):
+            print(os.path.relpath(p))

buildtools/meson.build

@@ -4,7 +4,7 @@
 subdir('pmdinfogen')
 
 pmdinfo = find_program('gen-pmdinfo-cfile.sh')
-
+list_dir_globs = find_program('list-dir-globs.py')
 check_experimental_syms = find_program('check-experimental-syms.sh')
 
 # set up map-to-def script using python, either built-in or external

doc/build-sdk-meson.txt

@@ -84,7 +84,10 @@ Project-specific options are passed used -Doption=value::
 
 	meson -Dmachine=default  # use builder-independent baseline -march
 
-Examples of setting the same options using meson configure::
+	meson -Ddisable_drivers=event/*,net/tap  # disable tap driver and all
+					# eventdev PMDs for a smaller build
+
+Examples of setting some of the same options using meson configure::
 
 	meson configure -Dwerror=true
 

drivers/meson.build

@@ -17,7 +17,8 @@ dpdk_driver_classes = ['common',
 	       'event',   # depends on common, bus, mempool and net.
 	       'baseband'] # depends on common and bus.
 
-disabled_drivers = get_option('disable_drivers').split(',')
+disabled_drivers = run_command(list_dir_globs, get_option('disable_drivers'),
+		).stdout().split()
 
 default_cflags = machine_args
 if cc.has_argument('-Wno-format-truncation')