feat: initial commit

This commit is contained in:
ptrcnull 2022-08-05 21:19:57 +02:00
commit 02ec07cef2
5 changed files with 96 additions and 0 deletions

22
LICENSE Normal file
View file

@ -0,0 +1,22 @@
Copyright (c) 2022 ptrcnull
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

31
README.md Normal file
View file

@ -0,0 +1,31 @@
# execline-state
> in spite of skarnet's "execline maintains no state"
a simple shift register built on piperw(1)
### usage
```
init-state <name>
load-state <name> <target>
save-state <name> <value>
```
```sh
#!/bin/execlineb
init-state flip
save-state flip "up"
forstdin -E line
load-state flip current
println "! state: $current"
ifelse { s6-test "$line" = "flip" } {
println "! flipping state"
ifelse { s6-test "$current" = "up" } {
save-state flip "down"
}
save-state flip "up"
}
save-state flip "$current"
```

16
init-state Executable file
View file

@ -0,0 +1,16 @@
#!/bin/execlineb
backtick -E top_fd {
pipeline { s6-ls /proc/self/fd }
s6-tail -n 1
}
backtick -E rdfd { s6-expr ${top_fd} + 1 }
backtick -E wrfd { s6-expr ${top_fd} + 2 }
piperw $rdfd $wrfd
importas -ui name 1
shift
export ELSTATE_${name} $rdfd
elgetpositionals
$@

12
load-state Executable file
View file

@ -0,0 +1,12 @@
#!/bin/execlineb
importas -ui name 1
importas -ui target 2
importas -i rdfd ELSTATE_${name}
fdswap 0 ${rdfd}
shift -n 2
elgetpositionals
forstdin -E -o 100 ${target} # chosen by fair dice roll
fdswap 0 ${rdfd}
$@

15
save-state Executable file
View file

@ -0,0 +1,15 @@
#!/bin/execlineb
importas -ui name 1
importas -ui value 2
importas -i rdfd ELSTATE_${name}
backtick -E wrfd { s6-expr "$rdfd" + 1 }
foreground {
fdmove -c 1 ${wrfd}
echo "$value"
}
shift -n 2
elgetpositionals
$@