[RFC PATCH 1/3] os: begin separating some OS compatibility from EAL

[Bruce Richardson <bruce.richardson@intel.com>]

Some library functionality we may want ahead of EAL build depends upon
some OS-specific functionality, so we create a new lib for that to be
built separately. For now, just includes fnmatch function for windows.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 lib/eal/windows/meson.build                       |  1 -
 lib/meson.build                                   | 11 ++++++-----
 lib/os/freebsd/fnmatch.c                          |  3 +++
 lib/os/linux/fnmatch.c                            |  3 +++
 lib/os/meson.build                                |  8 ++++++++
 lib/os/os.c                                       |  3 +++
 lib/os/version.map                                |  7 +++++++
 lib/{eal => os}/windows/fnmatch.c                 |  0
 lib/{eal/windows/include => os/windows}/fnmatch.h |  0
 9 files changed, 30 insertions(+), 6 deletions(-)
 create mode 100644 lib/os/freebsd/fnmatch.c
 create mode 100644 lib/os/linux/fnmatch.c
 create mode 100644 lib/os/meson.build
 create mode 100644 lib/os/os.c
 create mode 100644 lib/os/version.map
 rename lib/{eal => os}/windows/fnmatch.c (100%)
 rename lib/{eal/windows/include => os/windows}/fnmatch.h (100%)

diff --git a/lib/eal/windows/meson.build b/lib/eal/windows/meson.build
index 845e406ca1..e4b2427610 100644
--- a/lib/eal/windows/meson.build
+++ b/lib/eal/windows/meson.build
@@ -18,7 +18,6 @@ sources += files(
         'eal_mp.c',
         'eal_thread.c',
         'eal_timer.c',
-        'fnmatch.c',
         'getopt.c',
         'rte_thread.c',
 )
diff --git a/lib/meson.build b/lib/meson.build
index c648f7d800..7b61b2a5d7 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -9,6 +9,7 @@
 # given as a dep, no need to mention ring. This is especially true for the
 # core libs which are widely reused, so their deps are kept to a minimum.
 libraries = [
+        'os',   # load os compatibility material
         'kvargs', # eal depends on kvargs
         'telemetry', # basic info querying
         'eal', # everything depends on eal
@@ -106,6 +107,7 @@ if cc.has_argument('-Wno-format-truncation')
 endif
 
 enabled_libs = [] # used to print summary at the end
+default_deps = []
 
 foreach l:libraries
     build = true
@@ -124,11 +126,7 @@ foreach l:libraries
     # use "deps" for internal DPDK dependencies, and "ext_deps" for
     # external package/library requirements
     ext_deps = []
-    deps = []
-    # eal is standard dependency once built
-    if dpdk_conf.has('RTE_LIB_EAL')
-        deps += ['eal']
-    endif
+    deps = default_deps
 
     if disabled_libs.contains(l)
         build = false
@@ -271,4 +269,7 @@ foreach l:libraries
     if developer_mode
         message('lib/@0@: Defining dependency "@1@"'.format(l, name))
     endif
+    if name == 'os' or name == 'eal'
+        default_deps = [name]
+    endif
 endforeach
diff --git a/lib/os/freebsd/fnmatch.c b/lib/os/freebsd/fnmatch.c
new file mode 100644
index 0000000000..ca8a050fda
--- /dev/null
+++ b/lib/os/freebsd/fnmatch.c
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 Intel Corporation
+ */
diff --git a/lib/os/linux/fnmatch.c b/lib/os/linux/fnmatch.c
new file mode 100644
index 0000000000..ca8a050fda
--- /dev/null
+++ b/lib/os/linux/fnmatch.c
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 Intel Corporation
+ */
diff --git a/lib/os/meson.build b/lib/os/meson.build
new file mode 100644
index 0000000000..53949ca17e
--- /dev/null
+++ b/lib/os/meson.build
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2022 Intel Corporation
+
+includes += global_inc
+includes += include_directories(exec_env)
+sources += files(
+        exec_env / 'fnmatch.c',
+)
diff --git a/lib/os/os.c b/lib/os/os.c
new file mode 100644
index 0000000000..ca8a050fda
--- /dev/null
+++ b/lib/os/os.c
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2022 Intel Corporation
+ */
diff --git a/lib/os/version.map b/lib/os/version.map
new file mode 100644
index 0000000000..e1dbd6051e
--- /dev/null
+++ b/lib/os/version.map
@@ -0,0 +1,7 @@
+DPDK_22 {
+	global:
+
+	fnmatch;
+
+	local: *;
+};
diff --git a/lib/eal/windows/fnmatch.c b/lib/os/windows/fnmatch.c
similarity index 100%
rename from lib/eal/windows/fnmatch.c
rename to lib/os/windows/fnmatch.c
diff --git a/lib/eal/windows/include/fnmatch.h b/lib/os/windows/fnmatch.h
similarity index 100%
rename from lib/eal/windows/include/fnmatch.h
rename to lib/os/windows/fnmatch.h
-- 
2.34.1