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Format fix 2004/omoikane/README.md

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Cody Boone Ferguson committed 2023-04-26 05:28:50 -07:00
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@@ -1,11 +1,8 @@
# Best Utility
Don Yang
259 E. Bellbrook St.
Covina, CA 91722
US
http://uguu.org/
Don Yang
US
<http://uguu.org/>
## To build:
@@ -34,18 +31,18 @@ is modified to have the desired checksum! This does, we suppose,
solve the problem that inserting a checksum would change the file's
checksum; if you have to change it, you might as well change it!
This program was submitted under the name "Rinia", so the Author's
This program was submitted under the name `Rinia`, so the Author's
Comments refer to it as such.
## Author's remarks:
Rinia (1/14/04)
**Rinia (1/14/04)**
Rinia is a tool for embedding CRCs in text files. No need to assign
`Rinia` is a tool for embedding CRCs in text files. No need to assign
strange file names or package .SFVs with your files! Rinia will
insert a human-readable checksum string in the text itself! ^_^
insert a human-readable checksum string in the text itself! `^_^`
0. Usage `
### Usage `
```sh
rinia <infile> <layout> <outfile>
@@ -54,20 +51,20 @@ rinia <infile> <layout> <outfile>
All three arguments may reference the same file. All files is
assumed to be of ASCII character set.
1. Input %
### Input %
Any file larger than 8 bytes is valid. Upper limit on file size is
limited by memory.
If input file can't be loaded for any reason, Rinia will say "bad
If input file can't be loaded for any reason, `Rinia` will say "bad
input" and exit immediately.
2. Layout _
### Layout _
The layout file contains a map of where Rinia can patch. The
content consists of marker characters (where Rinia is allowed to
The layout file contains a map of where `Rinia` can patch. The
content consists of marker characters (where `Rinia` is allowed to
change in the original text) and other characters (where the
original text will stay as is). Rinia will select the marker
original text will stay as is). `Rinia` will select the marker
character using these heuristics:
1. Ignore all space/control/extended characters.
@@ -76,95 +73,103 @@ character using these heuristics:
frequency.
One way to create the layout file is to make a copy of the original
file, replace where you want Rinia to match with a rare character,
file, replace where you want `Rinia` to match with a rare character,
then replace the remaining ones with space. Often it's possible to
write the original file in such a way that it can be used as a
layout.
Example file/layout:
```
file: layout:
crc = ######## ... . XXXXXXXX
patch = ###### ..... . XXXXXX
other text here ..... .... ....
```
And Rinia may generate a file similar to this:
And `Rinia` may generate a file similar to this:
```
crc = 1bad73cf
patch = #FR-QQ
other text here
```
Note that the original file by itself is a valid layout file, since
Rinia will recognize that only # marks enough space to hold the
`Rinia` will recognize that only `#` marks enough space to hold the
checksum, and has the lowest frequency.
If layout file can't be used for any reason, Rinia will say "bad
If layout file can't be used for any reason, `Rinia` will say "bad
layout" and exit immediately.
3. Output m
### Output m
If Rinia finds a usuable checksum, she will say "OK." and write to
If `Rinia` finds a usable checksum, she will say "OK." and write to
the specified output file. Otherwise the exit message is "fail"
and nothing is written.
Chances of success and how long it takes to run to completion is
completely dominated by the layout file design. In general, Rinia
completely dominated by the layout file design. In general, `Rinia`
runs faster if the checksum is placed before the other marker
characters rather than after, e.g.:
```
a: X X XXX b: XXXXXXXX c: XXXXXXXX
XXXXXXXX X X XXX XXXXX
"a" usually takes the longest time, while "c" usually is the
```
`a` usually takes the longest time, while `c` usually is the
fastest.
That said, each run is randomized with respect to system time, so
it's not always certain whether Rinia will succeed in a short time
or not. In general, 5 marker characters is sufficient, and takes
it's not always certain whether `Rinia` will succeed in a short time
or not. In general, 5 marker characters are sufficient, and takes
a few minutes.
For reference, rinia.c was produced on a 1.7GHz machine (the
For reference, `rinia.c` was produced on a 1.7GHz machine (the
checksum is at line 17). Out of 25 runs, the shortest was 2
seconds while the longest took 5 minutes. Average was about a
minute. Checksum for this file (b7a81524) took about 4 minutes.
minute. Checksum for this file (`b7a81524`) took about 4 minutes.
4. Algorithm 3
### Algorithm
Inserting a checksum in the file you are computing the checksum of
isn't quite trivial, since changing the file content would change
the final checksum value.
To insert the checksum, Rinia first assumes a random final
To insert the checksum, `Rinia` first assumes a random final
checksum, insert that string, then modify other parts to compensate
for the change in content.
The compensation bytes are very easy to compute for binary files
with enough consecutive scratch areas, but for text files with
non-consecutive areas and limited degrees of freedom, Rinia has to
non-consecutive areas and limited degrees of freedom, `Rinia` has to
try out all character combinations. This is done in a hierarchical
fashion, computing only smallest partial checksum after each
change.
For computers few years ago, this is probably still too slow to be
acceptible... but at the speed the IOCCC judges run the contest
these days, I am sure you have enough patience for it ^_^;
acceptable... but at the speed the IOCCC judges run the contest
these days, I am sure you have enough patience for it `_^`
5. Source code =
### Source code
rinia.c should compile anywhere (but with a few warnings). I don't
have a big-endian machine to test but Rinia should work there as
`rinia.c` should compile anywhere (but with a few warnings). I don't
have a big-endian machine to test but `Rinia` should work there as
well. ASCII character set required though.
Code is formatted to the shape of "Rinia" from the anime/game
Code is formatted to the shape of "`Rinia`" from the anime/game
"Moekko Company". Of course at 90x50 it's hard to recognize anything
^_^;
`^_^`
Rinia is the slow but hardworking android. On some jobs she does
`Rinia` is the slow but hardworking android. On some jobs she does
very well, on others she would spend lots of time and effort but
still fail...
(text above is also included as an info file, so that the checksum
would match)
NOTE: the text above is also included as an info file but in original format, so
that the checksum would match. The above was formatted in markdown for GitHub
and the IOCCC website.
## Copyright and CC BY-SA 4.0 License: