rse 99/11/24 05:38:56
Modified: cgi-bin printenv
Log:
I know we don't want to see any "fancy" things in our printenv (as
they were already posted by various users over the last years), but
every time I need to use a little CGI script for testing purposes I get
annoyed by this really too weak printenv script. Sure, tables and other
stuff should be not our business, but at least the script should be a
little bit more robust and useful.
What I disliked most is that I usually have great problems to easily find a
variable (because the output is not sorted) and that various environment
values totally destroy the optical view on the table as a whole (mainly too
large values in $PATH and the nasty contents of SERVER_SIGNATURE). So here is
my minimal change to at least fix these problems without introducing fancy or
insecure stuff. Nevertheless feel free to back it out if you definitely
dislike any changes to printenv at all.
My changes are:
1. add a comment line to make it clear to the user that this is more or less
just a silly _demo_ script (for those who don't have Perl as their
secondary language beside their native language)
2. use content type text/plain instead of text/html to easily avoid printing
problems with variables like SERVER_SIGNATURE which contains HTML
code. This way we have to add extra escaping steps and the script
remains small.
3. sort the variables lexicographically in the output!
4. make sure very large lines (usually from $PATH) do not destroy the
total optical view on the table by cutting values and replacing
the missing stuff with "[...]".
5. surround values with quotes to allow one to better recognize newlines (as
in SERVER_SIGNATURE) and whitespaces and also print newlines
as \n and " as \" for a more Shell- and C-style syntax.
Revision Changes Path
1.4 +10 -3 apache-1.3/cgi-bin/printenv
Index: printenv
===================================================================
RCS file: /home/cvs/apache-1.3/cgi-bin/printenv,v
retrieving revision 1.3
retrieving revision 1.4
diff -u -r1.3 -r1.4
--- printenv 1996/12/09 03:51:57 1.3
+++ printenv 1999/11/24 13:38:55 1.4
@@ -1,7 +1,14 @@
#!/usr/local/bin/perl
+##
+## printenv -- demo CGI program which just prints its environment
+##
-print "Content-type: text/html\n\n";
-while (($key, $val) = each %ENV) {
- print "$key = $val<BR>\n";
+print "Content-type: text/plain\n\n";
+foreach $var (sort(keys(%ENV))) {
+ $val = $ENV{$var};
+ $val =~ s|\n|\\n|g;
+ $val =~ s|"|\\"|g;
+ $val = substr($val, 0, 100).'[...]' if (length($val) > 100);
+ print "${var}=\"${val}\"\n";
}
