add helper_functions

doc/helper_functions.7.md

@@ -0,0 +1,54 @@
+helper functions
+================
+
+you can find useful helper functions in `libdevuansdk/zlibs/helpers`. they are
+intended to help you with writing wrappers, as well as making my job easier
+within developing libdevuansdk. some of these functions are required for
+libdevuansdk to properly work as well.
+
+
+## build_image_dist()  
+this function is kind of a wrapper function, mostly used in `arm-sdk` to build a
+complete "dd-able" image from start to end. to run, it requires `$arch`,
+`$size`, `$parted_type`, `$workdir`, and `$strapdir` to be declared. as well as
+`$parted_root`, `$parted_boot` if `$parted_type=dos`, or `$gpt_root`,
+`$gpt_boot` if `$parted_type=gpt`. see `creating_wrappers(7)` for insight on
+these variables.
+
+the workflow of this function is bootstrapping a complete rootfs, creating a raw
+image, installing/compiling a kernel, rsyncing everything to the raw image, and
+finally, compressing the raw image.
+
+
+## devprocsys()  
+this function is a simple helper function that takes two arguments: `watdo` and
+`werdo`. it mounts or umounts `/sys`, `/dev`, `/dev/pts`, and `procfs` where you
+tell it to. for example:
+
+```
+devprocsys mount $strapdir
+devprocsys umount $strapdir
+```
+
+
+## findloopmapp()  
+this functions takes the raw image and finds a free loopdevice for it to be
+mounted. it calls `losetup(8)` and `kpartx(8)`.
+
+
+## qemu_install_user()  
+helper function to install the userspace qemu to `$strapdir`.
+
+
+## dpkgdivert()  
+this one takes two arguments, `watdo` and `werdo` (much like `devprocsys`). it
+will create a dpkg diversion in the place you tell it to and remove invoke-rc.d
+so that apt doesn't autostart daemons when they are installed.
+
+
+## enablessh()  
+this function will allow root login with password in the bootstrapped rootfs.
+
+
+## silly()  
+a funny function printing out random messages.

doc/nanodoc

@@ -24,7 +24,8 @@ desc="common.lib.for.devuan.sdks"
 
 pages="
     libdevuansdk.7
-	configuration.7"
+	configuration.7
+	helper_functions.7"
 
 
 generate_manpages() {