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fix Makefile and README.md for 2004/omoikane

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Landon Curt Noll committed 2023-03-21 21:55:20 -07:00
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2004/omoikane/README.md
+115 -105
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@@ -1,4 +1,4 @@
Best Utility:
# Best Utility:
Don Yang
259 E. Bellbrook St.
@@ -7,151 +7,161 @@ Best Utility:
http://uguu.org/
# To build:
Judges' Comments:
```sh
make
```
To build:
### To run:
make omoikane
```sh
./omoikane infile layout outfile
```
Try:
### Try:
./omoikane omoikane.info omoikane.info omoikane.output
```
./omoikane omoikane.info omoikane.info omoikane.output
```
For extra credit, spot the checksum in the source file itself.
What makes this one particularly interesting is that the checksum,
strictly speaking, isn't being computed at all. Rather, the file
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!
## Judges' comments:
This program was submitted under the name "Rinia", so the Author's
Comments refer to it as such.
For extra credit, spot the checksum in the source file itself.
What makes this one particularly interesting is that the checksum,
strictly speaking, isn't being computed at all. Rather, the file
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
Comments refer to it as such.
Selected Author's Comments:
## Author's comments:
Rinia (1/14/04)
Rinia (1/14/04)
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! ^_^
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! ^_^
0. Usage `
0. Usage `
rinia <infile> <layout> <outfile>
```sh
rinia <infile> <layout> <outfile>
```
All three arguments may reference the same file. All files is
assumed to be of ASCII character set.
All three arguments may reference the same file. All files is
assumed to be of ASCII character set.
1. Input %
1. Input %
Any file larger than 8 bytes is valid. Upper limit on file size is
limited by memory.
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
input" and exit immediately.
If input file can't be loaded for any reason, Rinia will say "bad
input" and exit immediately.
2. Layout _
2. Layout _
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
character using these heuristics:
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
character using these heuristics:
1. Ignore all space/control/extended characters.
2. Select characters that appeared 8 times in a row.
3. Of those selected characters, pick one with the lowest
frequency.
1. Ignore all space/control/extended characters.
2. Select characters that appeared 8 times in a row.
3. Of those selected characters, pick one with the lowest
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,
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.
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,
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:
Example file/layout:
file: layout:
crc = ######## ... . XXXXXXXX
patch = ###### ..... . XXXXXX
other text here ..... .... ....
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
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
checksum, and has the lowest frequency.
Note that the original file by itself is a valid layout file, since
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
layout" and exit immediately.
If layout file can't be used for any reason, Rinia will say "bad
layout" and exit immediately.
3. Output m
3. Output m
If Rinia finds a usuable checksum, she will say "OK." and write to
the specified output file. Otherwise the exit message is "fail"
and nothing is written.
If Rinia finds a usuable 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
runs faster if the checksum is placed before the other marker
characters rather than after, e.g.:
Chances of success and how long it takes to run to completion is
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: X X XXX b: XXXXXXXX c: XXXXXXXX
XXXXXXXX X X XXX XXXXX
"a" usually takes the longest time, while "c" usually is the
fastest.
"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
a few minutes.
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
a few minutes.
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.
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.
4. Algorithm 3
4. Algorithm 3
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.
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
checksum, insert that string, then modify other parts to compensate
for the change in content.
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
try out all character combinations. This is done in a hierarchical
fashion, computing only smallest partial checksum after each
change.
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
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 ^_^;
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 ^_^;
5. Source code =
5. 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
well. ASCII character set required though.
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
"Moekko Company". Of course at 90x50 it's hard to recognize anything
^_^;
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
very well, on others she would spend lots of time and effort but
still fail...
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)
(text above is also included as an info file, so that the checksum
would match)