*** rude top-posting fixed ***
Stephen Samuel wrote:
Timex wrote:
I want to delete all comments in .c file.
Size of .c file is very big.
Any good idea to do this?
Please show me example code.
Here's a perl script which will handle *MOST* sane C code...
Some things that it will miss (scan manually for it first:
a double quote inside of single quotes (e.g.)
char confusion = '"';
C-99 // comments like this
I'm sure that some people can come up with other convoluted
counter-examples.
It reads and plays with the entire file, so it will need to
hold at least two or three copies of it in RAM. (for today's
computers, that would be some number of megabytes).
If you want any of the above fixed, feel free to send me a
cheque.
_______________ _______________ _______________ _______
#!/usr/bin/perl
$s=join("",<>);
# printf "[[%s]]\n\n",$s;
$s=~ s/("(\\\\|\\"|[^"])*")|(\/\*([^*]|\*(?=[^\/]))*\*\/)|(\/\/.*)/[[$1 ]]/g;
printf "[[%s]]\n\n",$s;
_______________ _______________ _______________ _______
Yep, That's it... 5 lines including the shell header.
Please do not top-post.
The following AFAIK does not have the above faults, and does not
need to store any file copies, in fact not even any line copies.
It will probably be at least an order of magnitude faster.
/* File uncmntc.c - demo of a text filter
Strips C comments. Tested to strip itself
by C.B. Falconer. 2002-08-15
Public Domain. Attribution appreciated
report bugs to <mailto:cb***** ***@worldnet.at t.net>
*/
/* With gcc3.1, must omit -ansi to compile eol comments */
#include <stdio.h>
#include <stdlib.h>
static int ch, lastch;
/* ---------------- */
static void putlast(void)
{
if (0 != lastch) fputc(lastch, stdout);
lastch = ch;
ch = 0;
} /* putlast */
/* ---------------- */
/* gobble chars until star slash appears */
static int stdcomment(void )
{
int ch, lastch;
ch = 0;
do {
lastch = ch;
if (EOF == (ch = fgetc(stdin))) return EOF;
} while (!(('*' == lastch) && ('/' == ch)));
return ch;
} /* stdcomment */
/* ---------------- */
/* gobble chars until EOLine or EOF. i.e. // comments */
static int eolcomment(void )
{
int ch, lastch;
ch = '\0';
do {
lastch = ch;
if (EOF == (ch = fgetc(stdin))) return EOF;
} while (!(('\n' == ch) && ('\\' != lastch)));
return ch;
} /* eolcomment */
/* ---------------- */
/* echo chars until '"' or EOF */
static int echostring(void )
{
putlast();
if (EOF == (ch = fgetc(stdin))) return EOF;
do {
putlast();
if (EOF == (ch = fgetc(stdin))) return EOF;
} while (!(('"' == ch) && ('\\' != lastch)));
return ch;
} /* echostring */
/* ---------------- */
int main(void)
{
lastch = '\0';
while (EOF != (ch = fgetc(stdin))) {
if ('/' == lastch)
if (ch == '*') {
lastch = '\0';
if (EOF == stdcomment()) break;
ch = ' ';
putlast();
}
else if (ch == '/') {
lastch = '\0';
if (EOF == eolcomment()) break;
ch = '\n';
putlast(); // Eolcomment here
// Eolcomment line \
with continuation line.
}
else {
putlast();
}
else if (('"' == ch) && ('\\' != lastch)
&& ('\'' != lastch)) {
if ('"' != (ch = echostring())) {
fputs("\"Unterm inated\" string\n", stderr);
fputs("checking for\
continuation line string\n", stderr);
fputs("checking for" "concat string\n", stderr);
return EXIT_FAILURE;
}
putlast();
}
else {
putlast();
}
} /* while */
putlast(/* embedded comment */);
return 0;
} /* main */
--
Chuck F (cb********@yah oo.com) (cb********@wor ldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home .att.net> USE worldnet address!
