Adopt pyzfs from ClusterHQ

This commit introduces several changes:

 * Update LICENSE and project information

 * Give a good PEP8 talk to existing Python source code

 * Add RPM/DEB packaging for pyzfs

 * Fix some outstanding issues with the existing pyzfs code caused by
   changes in the ABI since the last time the code was updated

 * Integrate pyzfs Python unittest with the ZFS Test Suite

 * Add missing libzfs_core functions: lzc_change_key,
   lzc_channel_program, lzc_channel_program_nosync, lzc_load_key,
   lzc_receive_one, lzc_receive_resumable, lzc_receive_with_cmdprops,
   lzc_receive_with_header, lzc_reopen, lzc_send_resume, lzc_sync,
   lzc_unload_key, lzc_remap

Note: this commit slightly changes zfs_ioc_unload_key() ABI. This allow
to differentiate the case where we tried to unload a key on a
non-existing dataset (ENOENT) from the situation where a dataset has
no key loaded: this is consistent with the "change" case where trying
to zfs_ioc_change_key() from a dataset with no key results in EACCES.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: loli10K <[email protected]>
Closes #7230

1 files changed, 125 insertions, 0 deletions

diff --git a/config/always-pyzfs.m4 b/config/always-pyzfs.m4
new file mode 100644
index 000000000..1df11a5d7
--- /dev/null
+++ b/config/always-pyzfs.m4
@@ -0,0 +1,125 @@
+dnl #
+dnl # ZFS_AC_PYTHON_MODULE(module_name, [action-if-true], [action-if-false])
+dnl #
+dnl # Checks for Python module. Freely inspired by AX_PYTHON_MODULE
+dnl # https://www.gnu.org/software/autoconf-archive/ax_python_module.html
+dnl #
+AC_DEFUN([ZFS_AC_PYTHON_MODULE],[
+	PYTHON_NAME=`basename $PYTHON`
+	AC_MSG_CHECKING([for $PYTHON_NAME module: $1])
+	$PYTHON -c "import $1" 2>/dev/null
+	if test $? -eq 0;
+	then
+		AC_MSG_RESULT(yes)
+		m4_ifvaln([$2], [$2])
+	else
+		AC_MSG_RESULT(no)
+		m4_ifvaln([$3], [$3])
+	fi
+])
+
+dnl #
+dnl # ZFS_AC_PYTHON_VERSION(version, [action-if-true], [action-if-false])
+dnl #
+dnl # Verify Python version
+dnl #
+AC_DEFUN([ZFS_AC_PYTHON_VERSION], [
+	AC_MSG_CHECKING([for a version of Python $1])
+	version_check=`$PYTHON -c "import sys; print (sys.version.split()[[0]] $1)"`
+	if test "$version_check" = "True";
+	then
+		AC_MSG_RESULT(yes)
+		m4_ifvaln([$2], [$2])
+	else
+		AC_MSG_RESULT(no)
+		m4_ifvaln([$3], [$3])
+	fi
+
+])
+
+AC_DEFUN([ZFS_AC_CONFIG_ALWAYS_PYZFS], [
+	PYTHON_REQUIRED_VERSION="<= '2.7.x'"
+
+	AC_ARG_ENABLE([pyzfs],
+		AC_HELP_STRING([--enable-pyzfs],
+		[install libzfs_core python bindings @<:@default=check@:>@]),
+		[enable_pyzfs=$enableval],
+		[enable_pyzfs=check])
+
+	AM_PATH_PYTHON([2.7], [], [
+		AS_IF([test ! "x$enable_pyzfs" = xyes], [
+			AC_MSG_ERROR("python >= 2.7 is not installed")
+		], [test ! "x$enable_pyzfs" = xno], [
+			enable_pyzfs=no
+		])
+	])
+	AM_CONDITIONAL([HAVE_PYTHON], [test "$PYTHON" != :])
+
+	dnl #
+	dnl # Python 2.7.x is supported, other versions (3.5) are not yet
+	dnl #
+	AS_IF([test "x$enable_pyzfs" = xcheck], [
+		ZFS_AC_PYTHON_VERSION([$PYTHON_REQUIRED_VERSION], [], [
+			AS_IF([test "x$enable_pyzfs" = xyes], [
+				AC_MSG_ERROR("Python $PYTHON_REQUIRED_VERSION is not available")
+			], [test ! "x$enable_pyzfs" = xno], [
+				enable_pyzfs=no
+			])
+		])
+	])
+
+	dnl #
+	dnl # Require python-devel libraries
+	dnl #
+	AS_IF([test "x$enable_pyzfs" = xcheck], [
+		AX_PYTHON_DEVEL([$PYTHON_REQUIRED_VERSION], [
+			AS_IF([test "x$enable_pyzfs" = xyes], [
+				AC_MSG_ERROR("Python development library is not available")
+			], [test ! "x$enable_pyzfs" = xno], [
+				enable_pyzfs=no
+			])
+		])
+	])
+
+	dnl #
+	dnl # Python "setuptools" module is required to build and install pyzfs
+	dnl #
+	AS_IF([test "x$enable_pyzfs" = xcheck], [
+		ZFS_AC_PYTHON_MODULE([setuptools], [], [
+			AS_IF([test "x$enable_pyzfs" = xyes], [
+				AC_MSG_ERROR("python-setuptools is not installed")
+			], [test ! "x$enable_pyzfs" = xno], [
+				enable_pyzfs=no
+			])
+		])
+	])
+
+	dnl #
+	dnl # Python "cffi" module is required to run pyzfs
+	dnl #
+	AS_IF([test "x$enable_pyzfs" = xcheck], [
+		ZFS_AC_PYTHON_MODULE([cffi], [], [
+			AS_IF([test "x$enable_pyzfs" = xyes], [
+				AC_MSG_ERROR("python-cffi is not installed")
+			], [test ! "x$enable_pyzfs" = xno], [
+				enable_pyzfs=no
+			])
+		])
+	])
+
+	dnl #
+	dnl # Set enable_pyzfs to 'yes' if every check passed
+	dnl #
+	AS_IF([test "x$enable_pyzfs" = xcheck], [enable_pyzfs=yes])
+
+	AM_CONDITIONAL([PYZFS_ENABLED], [test x$enable_pyzfs = xyes])
+	AC_SUBST([PYZFS_ENABLED], [$enable_pyzfs])
+
+	AS_IF([test "x$enable_pyzfs" = xyes], [
+		DEFINE_PYZFS='--define "_pyzfs 1"'
+	],[
+		DEFINE_PYZFS=''
+	])
+	AC_SUBST(DEFINE_PYZFS)
+	AC_SUBST(pythonsitedir, [$PYTHON_SITE_PKG])
+])