shell/cmds: add genfile command

[benpicco]

Contribution description

Often it is quite handy to have a file with a known and easy to inspect content for transmission tests.

This adds a genfile command where a file with set number of rows (blocks) of varying size can be generated.

It is easy to visually identify corruptions to this file patter.

Testing procedure

The command has been added to tests/vfs_default:

> genfile -?
missing argument
usage: genfile [-o <file>] [-b <block size>] [-n num blocks]

> genfile
|000|0000000000000000000000000000000000000000000000000000000000
|001|1111111111111111111111111111111111111111111111111111111111
|002|2222222222222222222222222222222222222222222222222222222222
|003|3333333333333333333333333333333333333333333333333333333333
|004|4444444444444444444444444444444444444444444444444444444444
|005|5555555555555555555555555555555555555555555555555555555555
|006|6666666666666666666666666666666666666666666666666666666666
|007|7777777777777777777777777777777777777777777777777777777777
|008|8888888888888888888888888888888888888888888888888888888888
|009|9999999999999999999999999999999999999999999999999999999999
|010|aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
|011|bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
|012|cccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
|013|dddddddddddddddddddddddddddddddddddddddddddddddddddddddddd
|014|eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
|015|ffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
|016|gggggggggggggggggggggggggggggggggggggggggggggggggggggggggg
|017|hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
|018|iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
|019|jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
|020|kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
|021|llllllllllllllllllllllllllllllllllllllllllllllllllllllllll
|022|mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
|023|nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn
|024|oooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
|025|pppppppppppppppppppppppppppppppppppppppppppppppppppppppppp
|026|qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
|027|rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
|028|ssssssssssssssssssssssssssssssssssssssssssssssssssssssssss
|029|tttttttttttttttttttttttttttttttttttttttttttttttttttttttttt
|030|uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
|031|vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

> genfile -o /nvm0/test.txt

> ls /nvm0
./
../
hello.txt	18 B
test.txt	2048 B
total 2 files

Issues/PRs references

[riot-ci]

Murdock results

✔️ PASSED

e2b03af tests/vfs_default: enable genfile command

Success	Failures	Total	Runtime
6933	0	6933	12m:23s

Artifacts

• Documentation preview

[Teufelchen1]

Looks good, only nits.

Side note: The usage of vfs on native is confusing and poorly documented. I did not succeed to properly tests this 🤡

[benpicco]

bors merge

[bors]

Build succeeded!

The publicly hosted instance of bors-ng is deprecated and will go away soon.

If you want to self-host your own instance, instructions are here.
For more help, visit the forum.

If you want to switch to GitHub's built-in merge queue, visit their help page.

• Murdock
• static-tests
• tools-build-success