kmod: drop darwin support

commit 7a2c07d29b "kmod: enable on darwin" added darwin
support mostly for `depmod` to be able to build `linux` kernel
on `darwin`.

In version 30 kmod requires more and more linux syscalls to build.
Instead of patching it for darwin let's drop it's support instead.

Maybe `depmod` could be packaged using some other way if needed.

Related: https://github.com/NixOS/nixpkgs/pull/182720 removed
`kmod` use on `darwin` from rare packages that still pulled it in.

pkgs/os-specific/linux/kmod/darwin.patch

@@ -1,138 +0,0 @@
-diff --git a/Makefile.am b/Makefile.am
-index 194e111..0a095b5 100644
---- a/Makefile.am
-+++ b/Makefile.am
-@@ -80,8 +80,7 @@ EXTRA_DIST += libkmod/README \
- 	libkmod/COPYING testsuite/COPYING tools/COPYING COPYING
- 
- libkmod_libkmod_la_LDFLAGS = $(AM_LDFLAGS) \
--	-version-info $(LIBKMOD_CURRENT):$(LIBKMOD_REVISION):$(LIBKMOD_AGE) \
--	-Wl,--version-script=$(top_srcdir)/libkmod/libkmod.sym
-+	-version-info $(LIBKMOD_CURRENT):$(LIBKMOD_REVISION):$(LIBKMOD_AGE)
- libkmod_libkmod_la_DEPENDENCIES = \
- 	shared/libshared.la \
- 	${top_srcdir}/libkmod/libkmod.sym
-@@ -91,8 +90,7 @@ libkmod_libkmod_la_LIBADD = \
- 
- noinst_LTLIBRARIES += libkmod/libkmod-internal.la
- libkmod_libkmod_internal_la_SOURCES = $(libkmod_libkmod_la_SOURCES)
--libkmod_libkmod_internal_la_LDFLAGS = $(AM_LDFLAGS) \
--	-Wl,--version-script=$(top_srcdir)/libkmod/libkmod.sym
-+libkmod_libkmod_internal_la_LDFLAGS = $(AM_LDFLAGS)
- libkmod_libkmod_internal_la_DEPENDENCIES  = $(libkmod_libkmod_la_DEPENDENCIES)
- libkmod_libkmod_internal_la_LIBADD = $(libkmod_libkmod_la_LIBADD)
- 
-diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c
-index 889f264..6f0a285 100644
---- a/libkmod/libkmod-module.c
-+++ b/libkmod/libkmod-module.c
-@@ -787,7 +787,11 @@ KMOD_EXPORT int kmod_module_remove_module(struct kmod_module *mod,
- 	flags &= KMOD_REMOVE_FORCE;
- 	flags |= KMOD_REMOVE_NOWAIT;
- 
-+#if defined(__linux__)
- 	err = delete_module(mod->name, flags);
-+#else
-+	err = -1;
-+#endif
- 	if (err != 0) {
- 		err = -errno;
- 		ERR(mod->ctx, "could not remove '%s': %m\n", mod->name);
-@@ -879,7 +883,11 @@ KMOD_EXPORT int kmod_module_insert_module(struct kmod_module *mod,
- 	}
- 	size = kmod_file_get_size(mod->file);
- 
-+#if defined(__linux__)
- 	err = init_module(mem, size, args);
-+#else
-+	err = -1;
-+#endif
- init_finished:
- 	if (err < 0) {
- 		err = -errno;
-diff --git a/libkmod/libkmod-signature.c b/libkmod/libkmod-signature.c
-index 429ffbd..17a3b9c 100644
---- a/libkmod/libkmod-signature.c
-+++ b/libkmod/libkmod-signature.c
-@@ -17,7 +17,10 @@
-  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
-  */
- 
-+#if defined(__linux__)
- #include <endian.h>
-+#endif
-+
- #include <inttypes.h>
- #include <stdio.h>
- #include <stdlib.h>
-diff --git a/shared/macro.h b/shared/macro.h
-index 4fc5405..b5a2702 100644
---- a/shared/macro.h
-+++ b/shared/macro.h
-@@ -53,6 +53,10 @@
- #define CONCATENATE(x, y) XCONCATENATE(x, y)
- #define UNIQ(x) CONCATENATE(x, __COUNTER__)
-
-+#if !defined(__linux__)
-+#define program_invocation_short_name getprogname()
-+#endif
-+
- /* Temporaries for importing index handling */
- #define NOFAIL(x) (x)
- #define fatal(x...) do { } while (0)
-diff --git a/shared/missing.h b/shared/missing.h
-index 4c0d136..ad8ec0f 100644
---- a/shared/missing.h
-+++ b/shared/missing.h
-@@ -45,6 +45,9 @@ static inline int finit_module(int fd, const char *uargs, int flags)
- #endif
- 
- #if !HAVE_DECL_BE32TOH
-+
-+#if defined(__linux__)
-+
- #include <endian.h>
- #include <byteswap.h>
- #if __BYTE_ORDER == __LITTLE_ENDIAN
-@@ -52,4 +55,16 @@ static inline int finit_module(int fd, const char *uargs, int flags)
- #else
- #define be32toh(x) (x)
- #endif
-+
-+#elif defined(__APPLE__)
-+
-+#include <libkern/OSByteOrder.h>
-+#define be32toh(x) OSSwapBigToHostInt32(x)
-+
-+#else
-+
-+#error No be32toh known for platform
-+
-+#endif
-+
- #endif
-diff --git a/shared/util.c b/shared/util.c
-index fd2028d..ecb0141 100644
---- a/shared/util.c
-+++ b/shared/util.c
-@@ -367,7 +367,7 @@ char *path_make_absolute_cwd(const char *p)
- 	if (path_is_absolute(p))
- 		return strdup(p);
- 
--	cwd = get_current_dir_name();
-+	cwd = getcwd(NULL, 0);
- 	if (!cwd)
- 		return NULL;
- 
---- a/shared/util.h	2018-01-31 18:10:59.000000000 +0100
-+++ b/shared/util.h	2020-12-28 19:48:21.000000000 +0100
-@@ -7,6 +7,9 @@
- #include <stdio.h>
- #include <sys/types.h>
- #include <sys/stat.h>
-+#ifdef __APPLE__
-+#include <libgen.h>
-+#endif
- 
- #include <shared/macro.h>
- 

pkgs/os-specific/linux/kmod/default.nix

@@ -31,7 +31,7 @@ in stdenv.mkDerivation rec {
 
     docbook_xml_dtd_42 # for the man pages
   ] ++ lib.optionals withDevdoc [ docbook_xml_dtd_43 gtk-doc ];
-  buildInputs = [ xz zstd ] ++ lib.optional stdenv.isDarwin elf-header;
+  buildInputs = [ xz zstd ];
 
   preConfigure = ''
     ./autogen.sh
@@ -46,7 +46,6 @@ in stdenv.mkDerivation rec {
   ] ++ lib.optional withStatic "--enable-static";
 
   patches = [ ./module-dir.patch ]
-    ++ lib.optional stdenv.isDarwin ./darwin.patch
     ++ lib.optional withStatic ./enable-static.patch;
 
   postInstall = ''
@@ -77,7 +76,7 @@ in stdenv.mkDerivation rec {
     downloadPage = "https://www.kernel.org/pub/linux/utils/kernel/kmod/";
     changelog = "https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/plain/NEWS?h=v${version}";
     license = with licenses; [ lgpl21Plus gpl2Plus ]; # GPLv2+ for tools
-    platforms = platforms.unix;
+    platforms = platforms.linux;
     maintainers = with maintainers; [ artturin ];
   };
 }