[dpdk-dev] [PATCH v2] buildtools: fix build with meson 0.60

[Bruce Richardson]

Meson 0.60 switched the format of uninstalled static libraries
to thin archives, that is, they contain only paths to object files,
not the files themselves. Files cannot be extracted in this case,
resulting in build errors:

    ar: `x' cannot be used on thin archives.

Handle thin archives when invoking pmdinfogen by directly using the
files referenced in the archive, when they already exist, and extracting
them if not.

Bugzilla ID: 836
Fixes: e6e9730c7066 ("buildtools: support object file extraction for Windows")
Cc: stable at dpdk.org

Reported-by: Michal Berger <michallinuxstuff at gmail.com>
Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---

v2:
	Reworked to not check explicitly for thin archives by checking for
	specific bytes in the file, but instead by checking file by file if
	an object path from the .a file exists already.
	[Kept Dmitry's signoff since v2 re-uses some snippets and commit log
	messages from v1]

---
 buildtools/gen-pmdinfo-cfile.py | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/buildtools/gen-pmdinfo-cfile.py b/buildtools/gen-pmdinfo-cfile.py
index 58fe3ad152..5fbd51658a 100644
--- a/buildtools/gen-pmdinfo-cfile.py
+++ b/buildtools/gen-pmdinfo-cfile.py
@@ -9,12 +9,13 @@

 _, tmp_root, ar, archive, output, *pmdinfogen = sys.argv
 with tempfile.TemporaryDirectory(dir=tmp_root) as temp:
-    run_ar = lambda command: subprocess.run(
-        [ar, command, os.path.abspath(archive)],
-        stdout=subprocess.PIPE, check=True, cwd=temp
-    )
-    # Don't use "ar p", because its output is corrupted on Windows.
-    run_ar("x")
-    names = run_ar("t").stdout.decode().splitlines()
-    paths = [os.path.join(temp, name) for name in names]
+    paths = []
+    for name in subprocess.run([ar, "t", archive], stdout=subprocess.PIPE,
+                               check=True).stdout.decode().splitlines():
+        if os.path.exists(name):
+            paths.append(name)
+        else:
+            subprocess.run([ar, "x", os.path.abspath(archive), name],
+                           check=True, cwd=temp)
+            paths.append(os.path.join(temp, name))
     subprocess.run(pmdinfogen + paths + [output], check=True)
--
2.32.0