helper_functions.7.md (2018B)
1 helper functions 2 ================ 3 4 you can find useful helper functions in `libdevuansdk/zlibs/helpers`. they are 5 intended to help you with writing wrappers, as well as making my job easier 6 within developing libdevuansdk. some of these functions are required for 7 libdevuansdk to properly work as well. 8 9 10 ## build_arm_dist() 11 this function is kind of a wrapper function, mostly used in `arm-sdk` to build 12 a complete "dd-able" image from start to end. to run, it requires `$workdir` 13 `$strapdir`, and `$os`, `$arch`, `$size`, `$parted_type`, `$bootfs`, defined. 14 additionally, `$dos_root`, `$dos_boot` if `$parted_type=dos`, or `$gpt_root`, 15 `$gpt_boot` if `$parted_type=gpt`. see `creating_wrappers(7)` for insight on 16 these variables. 17 18 the workflow of this function is bootstrapping a complete rootfs, creating a raw 19 image, installing/compiling a kernel, rsyncing everything to the raw image, and 20 finally, compressing the raw image. 21 22 23 ## devprocsys() 24 this function is a simple helper function that takes two arguments: `watdo` and 25 `werdo`. it mounts or umounts `/sys`, `/dev`, `/dev/pts`, and `procfs` where you 26 tell it to. for example: 27 28 ``` 29 devprocsys mount $strapdir 30 devprocsys umount $strapdir 31 ``` 32 33 34 ## findloopmapp() 35 this functions takes the raw image and finds a free loopdevice for it to be 36 mounted. it calls `losetup(8)` and `kpartx(8)`. 37 38 39 ## qemu_install_user() 40 helper function to install the userspace qemu to `$strapdir`. 41 42 43 ## dpkgdivert() 44 this one takes two arguments, `watdo` and `werdo` (much like `devprocsys`). it 45 will create a dpkg diversion in the place you tell it to and remove invoke-rc.d 46 so that apt doesn't autostart daemons when they are installed. 47 48 49 ## enablessh() 50 this function will allow root login with password in the bootstrapped rootfs. 51 52 53 ## chroot-script() 54 allows you to chroot inside the `$strapdir` and execute the 55 script/binary that's given to it. 56 takes an optional argument: `-d` (will call dpkgdivert on and off) 57 58 59 ## silly() 60 a funny function printing out random messages.