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Many updates/fixes to 2018/burton2

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This is a big commit but it should complete this entry and 2018 unless I
have missed something.

The make test rule was fixed. A script was not +x.

Renamed freqcount -> freqcount.sh (for browser/display).

Renamed mkkeywords -> mkkeywords.sh (for browser/display).

Renamed runtest -> runtest.sh (for browser/display).

Renamed spotcheck -> spotcheck.sh (for browser/display).

Renamed spotdiff -> spotdiff.sh (for browser/display).

Made tac.man proper man format and renamed tac.1.

Added tokcount.sh - a script that the author included in the remarks but
not in a script.

The renaming of files should be okay including the manifest (it is
believed this is true anyway).

Add try.sh script.

The READ_ME.txt was deleted as it had been renamed to author-README.txt
but the former was never deleted. This file was typo/format checked.

Format/typo check README.md file.
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Cody Boone Ferguson committed 2023-12-14 12:14:08 -08:00
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2018/burton2/README.md
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@@ -15,117 +15,114 @@ make
### Try:
```sh
./prog -i < prog.c
./prog -s < prog.c
./prog -sk < prog.c
```
If you get stuck, try:
```sh
make test
./try.sh
```
If you get really stuck, try:
```sh
man ./tac.man
man ./tac.1
```
## Judges' remarks:
They say size isn't everything, and in the case of IOCCC [iocccsize.c](https://www.ioccc.org/2018/iocccsize.c)
that is saying something! What is this program weighing and how much does it weigh?
They say size isn't everything, and in the case of IOCCC
[iocccsize.c](https://www.ioccc.org/2018/iocccsize.c) that is saying something!
What is this program weighing and how much does it weigh?
## Author's remarks:
### tac - tokenize and count C and derivative languages:
```
tac computes C program size
(obfuscated / otherwise)
by splitting code as tokens small,
ignoring space, then counting all.
`tac` computes C program size\
(obfuscated / otherwise)\
by splitting code as tokens small,\
ignoring space, then counting all.\
It tries quite hard to act the same
as counting tool of I-OCCC fame.
Some bugs were fixed, it's faster too,
and does more things, just add some glue!
It tries quite hard to act the same\
as counting tool of I-OCCC fame.\
Some bugs were fixed, it's faster too,\
and does more things, just add some glue!\
It does far more than print the size:
the token part's a better prize!
With each upon on a single line,
how many things can you design?
It does far more than print the size:\
the token part's a better prize!\
With each upon on a single line,\
how many things can you design?\
Included is a keyword sorter,
de-obfuscator, freq reporter.
With code produced as little parts,
just add your own creative arts.
Included is a keyword sorter,\
de-obfuscator, freq reporter.\
With code produced as little parts,\
just add your own creative arts.\
But first you have to figure out
the braces part, without a doubt!
And then the code - it isn't easy:
for as else? That's rather cheesy!
But first you have to figure out\
the braces part, without a doubt!\
And then the code - it isn't easy:\
for as else? That's rather cheesy!\
The rest of it is standard fare:
expressions strange, the globals bare,
confusing symbols one and oh,
and precedence you have to know.
The rest of it is standard fare:\
expressions strange, the globals bare,\
confusing symbols one and oh,\
and precedence you have to know.\
The keyword list was made external,
because of standards change eternal.
Thus other languages can now,
be counted just like C, somehow!
The keyword list was made external,\
because of standards change eternal.\
Thus other languages can now,\
be counted just like C, somehow!\
I hope you find this code obscure\
enough to win, and thus procure\
a public place for all to see\
how badly I can butcher C!\
I hope you find this code obscure
enough to win, and thus procure
a public place for all to see
how badly I can butcher C!
```
### Said another way....
`tac` is the inverse of `cat`(1): it un-concatenates its input into C tokens,
writing the token stream to `stdout`. There are options to suppress the token ids,
summarize the token counts, and several options to allow it to be compatible
with `iocccsize`.
writing the token stream to `stdout`. There are options to suppress the token
ids, summarize the token counts, and several options to allow it to be
compatible with `iocccsize`.
The token-based output is quite useful in analyzing source code (see below),
and the counter is more accurate than `iocccsize` (see below); but this can be
fixed by using the -c compatibility flag, restoring the following problems as
fixed by using the `-c` compatibility flag, restoring the following problems as
in the official tool:
* whitespace **within** a string is **not** counted;
this seems wrong, as these chars **are** significant
* "`{;}`" is not counted within a double-quoted string
* whitespace preceding a comment is char-counted, unless the comment starts a line
* `-k` processes the reserved words within `//` comments(!), but not `/*`, changing the counts
* Whitespace **within** a string is **not** counted;
this seems wrong, as these chars **are** significant.
* "`{;}`" is not counted within a double-quoted string.
* Whitespace preceding a comment is `char`-counted, unless the comment starts a
line.
* `-k` processes the reserved words within `//` comments(!), but not `/*`,
changing the counts.
The following bugs are always corrected:
* treats `/*/` as a complete comment (`/*/int if for/*/` has three keywords)
* Treats `/*/` as a complete comment (`/*/int if for/*/` has three keywords)
* `-k` enables `//*` or within a line comment `/*` to initiate a comment block until following `*/`
* `-k` processes double quote characters in `//` comments - thus a solitary
quote consumes everything until the next quote
* single quotes are not handled correctly (`'"'` starts a dquote in `iocccsize`)
* Single quotes are not handled correctly (`'"'` starts a double quote in `iocccsize`)
* `#ifndef` is omitted as a keyword (but `#ifdef` is allowed?)
* `I` is not a reserved word.
* `tac` correctly penetrates [23rd century cloaking technology][1]. ;-)
There is one (known) remaining problem with detection:
* comments between preprocessor hash and keyword are not replaced with whitespace;
* Comments between preprocessor hash and keyword are not replaced with whitespace;
the following counts #include as two tokens, `#` and `include` (not as a reserved word):
#/*this will not be counted*/include/*correctly*/<stdio.h>
```c
#/*this will not be counted*/include/*correctly*/<stdio.h>
```
Fixing this properly hampers backwards compatibility in counting. This requires
eliding comments during the translation phases (ISO 5.1.1.2, phase 3), and yet still
counting words correctly absent `-k`.
[1]: http://ioccc.org/2014/birken/hint.html "Best use of port 1701"
[1]: /2014/birken/README.md "Best use of port 1701"
### Backwards Compatibility:
@@ -135,10 +132,11 @@ counting words correctly absent `-k`.
find ~/src/obc -type f -name \*.c | wc
```
The discrepancies found are documented and explained in the file "discrepancies".
The discrepancies found are documented and explained in the file
[discrepancies.md](discrepancies.md).
```sh
find ~/src/obc -type f -a -name "*.c" | xargs ./spotcheck ./prog | ./spotdiff |
find ~/src/obc -type f -a -name "*.c" | xargs ./spotcheck.sh ./prog | ./spotdiff.sh |
grep -v keep | diff -bw - discrep* | grep "[<>] cl "
```
@@ -159,17 +157,17 @@ designed to allow exhaustive, hand-counted values for comparison with the tool v
These test cases were vital in debugging and regression testing, and provided a way to
determine which tool was correct when there were differences.
> A version of this tool in more clearly written C (tac.c)
> A version of this tool in more clearly written C ([tac.c](tac.c))
> is presented for the Judge's consideration as a more accurate replacement for `iocccsize`.
> This obfuscated entry is derived from (and compatible with) that code,
> but due to obfuscation, has had some significant, deep changes for the contest.
> Nevertheless, the more clearly written code remains a spoiler for this entry.
NB: `iocccsize` gets a different answer from `tac` on its own
([iocccsize.c]([iocccsize.c](https://www.ioccc.org/2018/iocccsize.c)) source code;
([iocccsize.c](/2018/iocccsize.c)) source code;
`tac` gets the correct answer. This is due to the aforementioned bugs within `iocccsize`,
proved by fixing
[iocccsize.c](https://www.ioccc.org/2018/iocccsize.c) with the included patch, so `iocccsize` reports
[iocccsize.c](/2018/iocccsize.c) with the included patch, so `iocccsize` reports
the correct answer for itself.
### But wait... There's More!
@@ -201,25 +199,27 @@ cat $* | ./prog -t | iskeyword | sort -k1nr
This script was used to "optimize" the reserved word order so the most frequent IOCCC
winning entry keywords are checked first.
> An interesting aside: as might be expected, obfuscation has changed the frequency of
> keyword distribution over time. The top five for the decades:
>\
> 1980s 1990s 2000s 2010s
> ----- ----- ----- -----
> 94 if 532 char 375 if 254 int
> 69 for 524 if 372 char 217 for
> 59 while 417 int 332 int 198 if
> 48 char 223 for 184 for 121 return
> 43 int 223 void 165 return 104 char
An interesting aside: as might be expected, obfuscation has changed the frequency of
keyword distribution over time. The top five for the decades:
```
1980s 1990s 2000s 2010s
----- ----- ----- -----
94 if 532 char 375 if 254 int
69 for 524 if 372 char 217 for
59 while 417 int 332 int 198 if
48 char 223 for 184 for 121 return
43 int 223 void 165 return 104 char
```
The keyword list is external to the program, and is easily changed, sorted, checked, verified.
This allows such additional programs in concert with the tool's primary operation.
A poor-man's de-obfuscator can be based upon the output of `tac -t` and a handful of
simple rules (and another use of the external keyword file).
A more refined version of this is included in the file `unob.sh`,
but the simple code below is a serviceable obfuscated C de-obfuscator in a _scripting language_.
It really is this easy with `tac`:
A poor-man's de-obfuscator can be based upon the output of `tac -t` and a
handful of simple rules (and another use of the external keyword file). A more
refined version of this is included in the file [unob.sh](unob.sh), but the
simple code below is a serviceable obfuscated C de-obfuscator in a _scripting
language_. It really is this easy with `tac`:
```sh
@@ -277,22 +277,22 @@ sed 's/^# .*$//' | sed 's/^#//' |
* Keywords follow the 2010s top five, without the `if`, for interesting flow control.
* Sometimes a `for` can be an `else` - [inconceivable][3]!
* I see the `getopt`. But "[where's the beef?][4]"
* No character constants, several int constants, and one string
* I see the `getopt(3)`. But "[where's the beef?][4]"
* No character constants, several `int` constants, and one string
(hint: which does not encode letters) -- how does this code parse code?
> Interesting aside: how many is "several int constants"?
>
> ./prog < prog.c 2>/dev/null | awk '$1~/260/{a[$2]++}END{for(i in a)print i,a[i]}'
> ... | wc
>
> Which numbers are most often used?
>
> ... | sort -k2nr | sed 5q
- Interesting aside: how many is "several `int` constants"?
./prog < prog.c 2>/dev/null | awk '$1~/260/{a[$2]++}END{for(i in a)print i,a[i]}'
... | wc
Which numbers are most often used?
... | sort -k2nr | sed 5q
* The code describes its function by careful arrangement of variables up front...
* ...coupled with a description of the typical IOCCC contestant, or at least the author
* Why shouldn't trigraph parsing be written in trigraph?
* Where [iocccsize.c](https://www.ioccc.org/2018/iocccsize.c) mocks, this code flaunts:
* Where [iocccsize.c](/2018/iocccsize.c) mocks, this code flaunts:
"_no matter how well you may think you understand this code, you don't, so don't mess with it. :-)_"
* `O,0,l,1` are used to confusing effect, local names obscure global names.
* Globals are used to pass information between routines: don't reorder "unrelated" statements....
@@ -304,6 +304,7 @@ sed 's/^# .*$//' | sed 's/^#//' |
[3]: https://www.youtube.com/watch?v=OHVjs4aobqs "Inconceivable"
[4]: https://www.youtube.com/watch?v=Ug75diEyiA0 "Where's the beef?"
### Rule 2:
The keyword list is externalized as an include file. This presents a useful
@@ -312,27 +313,28 @@ produced, but the tool can be rebuilt with any set of reserved words, just by
using a different list. For instance: removing all the secondary keywords;
removing all the C11 keywords; trying just K&R C. Since C++ and Java share the
same operators as C, just change the keyword list and `tac` will correctly
tokenize both of these; the tokens >>> and :: can be handled with a short
tokenize both of these; the tokens `>>>` and `::` can be handled with a short
post-filter ([tokenfix.sh](tokenfix.sh), included).
I believe this entry may also satisfy the request for gratuitous use of all the C11 keywords?
Whether this context satisfies "intended C language context" is a matter of interpretation. ;-)
And `tac` is ready for the IOCCC++ contest. And the IOJCC trashcan.
I believe this entry may also satisfy the request for gratuitous use of all the
C11 keywords? Whether this context satisfies "intended C language context" is a
matter of interpretation. ;-) And `tac` is ready for the IOCCC++ contest. And
the IOJCC trash can.
The following reserved word files are included:
kandr from my venerable 1978 18th printing "The C Programming Language"
v7unix 7th edition Unix source code, extracted from c00.c
kandr2 from my 1988 1st printing "The C Programming Language", 2e
ansi ANS X3.159-1989
c99 ISO/IEC 9899:1999(E)
c11 ISO/IEC 9899:201x(E) N1570
c++98 http://en.cppreference.com/w/cpp/keyword
c++11 ISO/IEC 14882:2011(E) N3337 2012-01-16
c++14 ISO/IEC 14882:2014(E) N4296 2014-11-09
java8 http://docs.oracle.com/javase/specs/index.html
ioccc.kw.freq c11 + additional words, sorted on frequency of occurrence in ioccc winners
* [kandr](kandr) from my venerable 1978 18th printing "The C Programming Language"
* [v7unix](v7unix) 7th edition Unix source code, extracted from c00.c
* [kandr2](kandr2) from my 1988 1st printing "The C Programming Language", 2e
* [ansi](ansi) ANSI X3.159-1989
* [c99](c99) ISO/IEC 9899:1999(E)
* [c11](c11) ISO/IEC 9899:201x(E) N1570
* [c++98](c++98) http://en.cppreference.com/w/cpp/keyword
* [c++11](c++11) ISO/IEC 14882:2011(E) N3337 2012-01-16
* [c++14](c++14) ISO/IEC 14882:2014(E) N4296 2014-11-09
* [java8](java8) <http://docs.oracle.com/javase/specs/index.html>
* [ioccc.kw.freq](ioccc.kw.freq) c11 + additional words, sorted on frequency of occurrence in IOCCC winners
NB: The keyword file used in this code is derived from the list in [iocccsize.c](https://www.ioccc.org/2018/iocccsize.c),
@@ -354,11 +356,12 @@ This also allows the builder to configure the amount of help a utility should pr
([you want a manpage? Because that's how you get a manpage.][5]) -- a rather
significant point of contention made moot.
There is definitely abuse of the Rule2 counter, exploiting a "feature" of `iocccsize`:
`iocccsize` does not Rule2 count {, } and ; when followed by whitespace -- even within a string!
Thus: Freecode, a simple, uncounted, highly obfuscated encoding of a central part
of this program. (The reserved word list is not Freecoded, both because it is useful
apart from the program, and because Freecode is not entirely free.*)
There is definitely abuse of the Rule2 counter, exploiting a "feature" of
`iocccsize`: `iocccsize` does not Rule2 count `{`, `}` and `;` when followed by
whitespace -- even within a string! Thus: Freecode, a simple, uncounted, highly
obfuscated encoding of a central part of this program. (The reserved word list
is not Freecoded, both because it is useful apart from the program, and because
Freecode is not entirely free.)
* Some restrictions apply. Not approved for all uses. Some assembly required.
@@ -370,12 +373,12 @@ The code is ANSI compliant, but it does have a string longer than 509 characters
It has been tested on OSX and Linux, Clang and GCC.
The code uses trigraphs, ironically: it parses trigraphs with trigraph code.
Because that's funny. And it remains obscure after, so trigraphs are not used for obfuscation.
Thus `-trigraphs -Wno-trigraphs` (which is also humorous).
Because that's funny. And it remains obscure after, so trigraphs are not used
for obfuscation. Thus `-trigraphs -Wno-trigraphs` (which is also humorous).
It's obfuscated C. Thus `-Wno-parentheses -Wno-empty-body -Wno-char-subscripts`.
The code uses unsigned chars, but C strings are signed. Thus `-Wno-pointer-sign`.
The code uses `unsigned char`s, but C strings are `signed`. Thus `-Wno-pointer-sign`.
NB: This is *not* a portability concern, the one string holds only printable ASCII characters.
Thus:
@@ -387,9 +390,9 @@ cc -ansi -Wall -trigraphs -Wno-trigraphs -Wno-parentheses -Wno-empty-body -Wno-c
### Coda:
[Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) was relentless in his pursuit of bugs.
Thanks to his reports, the version of `unob.sh` is stronger,
`tac` groks digraphs, `tokenfix` corrects for missing digraphs in `prog.c`,
and the program `manpage` was added to the corpus.
Thanks to his reports, the version of [unob.sh](unob.sh) is stronger,
`tac` groks digraphs, [tokenfix.sh](tokenfix.sh) corrects for missing digraphs
in [prog.c](prog.c), and the program [manpage.sh](manpage.sh) was added to the corpus.
[manpage.sh](manpage.sh) is a useful program that turns ASCII versions of man
pages (e.g. [tac.man](tac.man)) into real man pages. It works for C and C-like
@@ -401,14 +404,17 @@ are not recognised when written as `-rs` in prose).
Try:
```sh
./manpage tac
./manpage.sh tac
./manpage -h
./manpage -h | ./manpage
./manpage -h | ./manpage -R | less
./manpage -h | ./manpage -P | lpr
./manpage.sh -h
./manpage.sh -h | ./manpage.sh
./manpage.sh -h | ./manpage.sh -R | less
./manpage.sh -h | ./manpage.sh -P | lpr
```
NOTE: in 2023 the `tac.man` was updated to proper man format and renamed
[tac.1](tac.1).
## Copyright and CC BY-SA 4.0 License: