spdk: fix python installation prefix

without this change, we cannot import spdk

pkgs/development/libraries/spdk/0001-fix-setuptools-installation.patch

@@ -0,0 +1,29 @@
+From 3f718fc1873c9c138684ea019e9bd42c9b24506c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= <joerg@thalheim.io>
+Date: Tue, 28 Nov 2023 11:28:11 +0100
+Subject: [PATCH] fix setuptools installation
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Signed-off-by: Jörg Thalheim <joerg@thalheim.io>
+---
+ python/Makefile | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/python/Makefile b/python/Makefile
+index f835daa..b41995a 100644
+--- a/python/Makefile
++++ b/python/Makefile
+@@ -12,7 +12,7 @@ setup_cmd += --root $(DESTDIR)
+ endif
+ 
+ ifneq ($(CONFIG_PYDIR),)
+-setup_cmd += --install-purelib $(CONFIG_PYDIR)
++setup_cmd += --root / --prefix $(CONFIG_PYDIR)
+ purelibdir := $(CONFIG_PYDIR)
+ else
+ purelibdir := $(shell python3 -c "import sysconfig; print(sysconfig.get_paths()['purelib'])")
+-- 
+2.42.0
+

pkgs/development/libraries/spdk/default.nix

@@ -57,6 +57,7 @@ stdenv.mkDerivation rec {
   patches = [
     # https://review.spdk.io/gerrit/c/spdk/spdk/+/20394
     ./setuptools.patch
+    ./0001-fix-setuptools-installation.patch
   ];
 
   postPatch = ''
@@ -67,9 +68,13 @@ stdenv.mkDerivation rec {
 
   configureFlags = [
     "--with-dpdk=${dpdk}"
-    "--pydir=${placeholder "out"}/${python3.sitePackages}"
+    "--pydir=${placeholder "out"}"
   ];
 
+  postCheck = ''
+    python3 -m spdk
+  '';
+
   env.NIX_CFLAGS_COMPILE = "-mssse3"; # Necessary to compile.
   # otherwise does not find strncpy when compiling
   env.NIX_LDFLAGS = "-lbsd";