ccomment.c
translates
C++ programming language comments
(//..., which are sometimes used as a
non-standard extension in C source code)
to pure C comments
(/*...*/).
Care has been taken of:
strings,
character literals,
constructs like
'//.../*...*/'
and performance.
ccomment.c uses a simple, compact C/C++ programming language parser, which is implemented in C (not lex or yacc) as a state engine (10 * 7 matrix and accessor function). The focus was to keep it compact.
10 is the number of states
(see diagram below;
'literal' meaning character-literal
and 'string' meaning string-literal;
'code' is the start state);
7 is the alphabet size (/ * \ " '
newline and rest;
untagged transitions meaning the 'else' case
(rest and unhandled cases)).
Known limitations:
Trigraphs are not handled.
[That means
??/ is not recognized as the escape character
\,
??' is misinterpreted as quote,
etc.]
The simple (C++ comment able) C source code parser used by ccomment.c:
+-------------------+
| cppcommentquote |
+-------------------+
^ |
+----+ '\\'| | +----+
| v | v | v
+-------------------+ '\n' +-------------------+
| cppcomment |--+ | comment |
+-------------------+ | +-------------------+
^ | ^ ^ |
'/'| +---------- + +----+ | |'*'
| |'*' | '*'| v | v
+-------------------+ | +-------------------+
| precomment | | | postcomment |
+-------------------+ | +-------------------+
| | ^ | | |
'\''| |'"' '/'| | | +----+ |'/'
| | | v v | v v
| | +-------------------+
| | | code |
| | +-------------------+
| | ^ |'\'' ^ |'"'
| +------ | | ------- | | --+
v '\''| v '"'| v v
+-------------------+ +-------------------+
| literal | | string |
+-------------------+ +-------------------+
^ | ^ | ^ | ^ |
+----+ | |'\\' | |'\\' +----+
| v | v
+-------------------+ +-------------------+
| literalquote | | stringquote |
+-------------------+ +-------------------+
Keywords: C comments, C++ comments, comment, change, convert, translate, comment conversion, comment translation, source code, sources, source