[make-initrd] [PATCH v6 11/22] bootchain-core: introduces optional configuration capabilities

["Leonid Krivoshein" <klark.devel@gmail.com>]

The "chaind" daemon can be configured when building initramfs via the
configurations file /etc/sysconfig/bootchain, and not only through boot
parameters.

Signed-off-by: Leonid Krivoshein <klark.devel@gmail.com>
---
 features/bootchain-core/README.md                | 16 ++++++++++++++++
 .../data/bin/bootchain-sh-functions              | 10 +++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/features/bootchain-core/README.md b/features/bootchain-core/README.md
index ba66259..83897da 100644
--- a/features/bootchain-core/README.md
+++ b/features/bootchain-core/README.md
@@ -57,11 +57,27 @@ us to optimize fill in `initramfs` only which we are need.
   relative addressing it is safe in any case and can often be more convenient.
 - Allows you to work with shorter and more familiar paths to special files
   devices thanks to the use of `DEVNAME` along with `dev`.
+- The daemon can be configured when building initramfs via the included file
+  configurations of `/etc/sysconfig/bootchain`, and not only through boot
+  parameters, see the details in the corresponding section.
 
 Despite the differences, `chaind` is backward compatible with previously
 written steps for the `pipelined` daemon and does not require changes for
 configurations with `root=pipeline`.
 
+## Configuration
+
+The configuration is defined in the file `/etc/sysconfig/bootchain` when
+building the initramfs image, is optional, and may contain the following
+parameters:
+
+- `mntdir` - where to create subdirectories of the bootchain steps. In NATIVE
+  mode the default value is `/dev/bootchain`, in COMPATIBILITY mode with
+  `pipeline`, the default value is `/dev/pipeline`.
+
+Other `bootchain-*` modules can also use this configuration file for their
+own needs.
+
 ## External elements of the bootchain (steps-scripts)
 
 - `mountfs` - mounts a file or device from the result of the previous or other
diff --git a/features/bootchain-core/data/bin/bootchain-sh-functions b/features/bootchain-core/data/bin/bootchain-sh-functions
index 0eebbaf..8167e29 100644
--- a/features/bootchain-core/data/bin/bootchain-sh-functions
+++ b/features/bootchain-core/data/bin/bootchain-sh-functions
@@ -3,11 +3,19 @@
 if [ -z "${__bootchain_sh_functions-}" ]; then
 __bootchain_sh_functions=1
 
+[ ! -s /etc/sysconfig/bootchain ] ||
+	. /etc/sysconfig/bootchain
+
 . /.initrd/initenv
 . shell-signal
 
+if [ "${ROOT-}" = pipeline ]; then
+	mntdir="${mntdir:-/dev/pipeline}"
+else
+	mntdir="${mntdir:-/dev/bootchain}"
+fi
+
 handlerdir=/lib/bootchain
-[ "${ROOT-}" = pipeline ] && mntdir=/dev/pipeline || mntdir=/dev/bootchain
 
 
 check_parameter()
-- 
2.24.1