-package PLP;
+#--------------#
+ package PLP;
+#--------------#
-# Not to be used without the CGI script;
-
-our $VERSION = '3.04';
+use v5.6;
use PLP::Functions ();
use PLP::Fields;
use PLP::Tie::Delay;
use PLP::Tie::Print;
-=head1 PLP
-
-None of the functions in this module should be called by PLP scripts.
-
-Functions:
-
-=over 10
-
-=item sendheaders
-
-Sends the headers waiting in %PLP::Script::header
-
-=item source
+use strict;
-Given a filename and optional level (level should be C<0> if it isn't called
-by C<source> itself), and optional linespec (used by C<PLP::Functions::Include>),
-parses a PLP file and returns Perl code, ready to be eval'ed.
+our $VERSION = '3.13';
-=item error
+# subs in this package:
+# sendheaders Send headers
+# source($path, $level, $linespec) Read and parse .plp files
+# error($error, $type) Handle errors
+# _default_error($plain, $html) Default error handler
+# clean Reset variables
+# cgi_init Initialization for CGI
+# mod_perl_init($r) Initialization for mod_perl
+# start Start the initialized PLP script
+# everything Do everything: CGI
+# handler($r) Do everything: mod_perl
-Given a description OR number, returns a piece of HTML, OR prints error headers.
-
-=item start
-
-Inits everything, reads the first file, sets environment.
-
-=cut
+# Sends the headers waiting in %PLP::Script::header
sub sendheaders () {
our $sentheaders = 1;
- print STDOUT "Content-Type: text/plain\n\n" if $DEBUG & 2;
+ print STDOUT "Content-Type: text/plain\n\n" if $PLP::DEBUG & 2;
print STDOUT map("$_: $PLP::Script::header{$_}\n", keys %PLP::Script::header), "\n";
};
+# Given a filename and optional level (level should be 0 if the caller isn't
+# source() itself), and optional linespec (used by PLP::Functions::Include),
+# this function parses a PLP file and returns Perl code, ready to be eval'ed
sub source {
my ($path, $level, $linespec) = @_;
- $level = 0 if not defined $level;
+ $level = 0 if not defined $level;
$linespec = '1' if not defined $linespec;
+
our ($inA, $inB);
+
(my $file = $path) =~ s[.*/][];
+
my $source = $level
? qq/\cQ;\n#line 1 "$file"\nprint q\cQ/
: qq/\n#line 1 "$file"\nprint q\cQ/;
my $linenr = 0;
+
local *SOURCE;
- open SOURCE, $path or return $level
+ open SOURCE, '<', $path or return $level
? qq{\cQ; die qq[Can't open "\Q$path\E" (\Q$!\E)]; print q\cQ}
: qq{\n#line $linespec\ndie qq[Can't open "\Q$path\E" (\Q$!\E)];};
- LINE: while (defined (my $line = <SOURCE>)) {
+
+ LINE:
+ while (defined (my $line = <SOURCE>)) {
$linenr++;
for (;;) {
$line =~ /
\G # Begin where left off
( \z # End
- | <:=? | :> # PLP tags <:=? ... :>
+ | <:=? | :> # PLP tags <:= ... :> <: ... :>
| <\(.*?\)> # Include tags <(...)>
| <[^:(][^<:]* # Normal text
| :[^>][^<:]* # Normal text
}
}
$source .= "\cQ" unless $level;
+
return $source;
}
+# Handles errors, uses the sub reference $PLP::ERROR that gets two arguments:
+# the error message in plain text, and the error message with html entities
sub error {
my ($error, $type) = @_;
if (not defined $type or $type < 100) {
$PLP::ERROR->($plain, $html);
} else {
select STDOUT;
- my ($short, $long) = @{ +{
- 404 => [ 'Not Found', "The requested URL $ENV{REQUEST_URI} was not found on this server." ],
- 403 => [ 'Forbidden', "You don't have permission to access $ENV{REQUEST_URI} on this server." ],
- }->{$type} };
+ my ($short, $long) = @{
+ +{
+ 404 => [
+ 'Not Found',
+ "The requested URL $ENV{REQUEST_URI} was not found on this server."
+ ],
+ 403 => [
+ 'Forbidden',
+ "You don't have permission to access $ENV{REQUEST_URI} on this server."
+ ],
+ }->{$type}
+ };
print "Status: $type\nContent-Type: text/html\n\n",
qq{<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">\n},
"<html><head>\n<title>--$type $short</title>\n</head></body>\n",
}
}
+# This gets referenced as the initial $PLP::ERROR
sub _default_error {
my ($plain, $html) = @_;
print qq{<table border=1 class="PLPerror"><tr><td>},
qq{<span><b>Debug information:</b><BR>$html</td></tr></table>};
}
-sub start {
- my $file = $ENV{PATH_TRANSLATED};
+# This cleans up from previous requests, and sets the default $PLP::DEBUG
+sub clean {
+ @PLP::END = ();
+ $PLP::code = '';
+ $PLP::sentheaders = 0;
+ $PLP::inA = 0;
+ $PLP::inB = 0;
+ $PLP::DEBUG = 1;
+ delete @ENV{ grep /^PLP_/, keys %ENV };
+}
+
+# The *_init subs do the following:
+# o Set $PLP::code to the initial code
+# o Set $ENV{PLP_*} and makes PATH_INFO if needed
+# o Change the CWD
+
+# This sub is meant for CGI requests only, and takes apart PATH_TRANSLATED
+# to find the file.
+sub cgi_init {
+ my $file = defined $_[0] ? $_[0] : $ENV{PATH_TRANSLATED};
$ENV{PLP_NAME} = $ENV{PATH_INFO};
my $path_info;
while (not -f $file) {
if (not $file =~ s/(\/+[^\/]*)$//) {
print STDERR "PLP: Not found: $ENV{PATH_TRANSLATED} ($ENV{REQUEST_URI})\n";
-
- if (exists $ENV{MOD_PERL}) {
- Apache->request->uri($ENV{REQUEST_URI});
- print STDOUT "Status: 404 Not Found";
- Apache::exit();
- } else {
- PLP::error(undef, 404);
- exit;
- }
+ PLP::error(undef, 404);
+ exit;
}
my $pi = $1;
$ENV{PLP_NAME} =~ s/\Q$pi\E$//;
$path_info = $pi . $path_info;
}
- if (exists $ENV{MOD_PERL}) {
- Apache->request->uri($ENV{REQUEST_URI});
- }
-
if (not -r $file) {
print STDERR "PLP: Can't read: $ENV{PATH_TRANSLATED} ($ENV{REQUEST_URI})\n";
- if (exists $ENV{MOD_PERL}) {
- print STDOUT "Status: 403 Forbidden";
- Apache::exit();
- } else {
- PLP::error(undef, 403);
- exit;
- }
+ PLP::error(undef, 403);
+ exit;
}
delete @ENV{
chdir $dir;
$PLP::code = PLP::source($file, 0);
+}
+# This is the mod_perl initializer.
+# Returns 0 on success.
+sub mod_perl_init {
+ my $r = shift;
+
+ $ENV{PLP_FILENAME} = my $filename = $r->filename;
+
+ unless (-f $filename) {
+ return Apache::Constants::NOT_FOUND();
+ }
+ unless (-r _) {
+ return Apache::Constants::FORBIDDEN();
+ }
+
+ (my $dir) = $filename =~ m!(.*)/!s;
+ chdir $dir;
+ $ENV{PLP_NAME} = $r->uri;
+ $PLP::code = PLP::source($r->filename);
+
+ return 0; # OK
+}
+
+# Let the games begin!
+# No lexicals may exist at this point.
+sub start {
+ no strict;
tie *PLPOUT, 'PLP::Tie::Print';
select PLPOUT;
$PLP::ERROR = \&_default_error;
+
+ PLP::Fields::doit();
+ {
+ package PLP::Script;
+ use vars qw(%headers %header %cookies %cookie %get %post %fields);
+ *headers = \%header;
+ *cookies = \%cookie;
+ PLP::Functions->import();
+ # No lexicals may exist at this point.
+ eval qq{ package PLP::Script; $PLP::code; };
+ PLP::error($@, 1) if $@ and $@ !~ /\cS\cT\cO\cP/;
+ eval { package PLP::Script; $_->() for reverse @PLP::END };
+ PLP::error($@, 1) if $@ and $@ !~ /\cS\cT\cO\cP/;
+ }
+ PLP::sendheaders() unless $PLP::sentheaders;
+ select STDOUT;
+ undef *{"PLP::Script::$_"} for keys %PLP::Script::;
+# Symbol::delete_package('PLP::Script');
+# The above does not work. TODO - find out why not.
+}
+
+# This is run by the CGI script.
+# The CGI script is just:
+# #!/usr/bin/perl
+# use PLP;
+# PLP::everything();
+sub everything {
+ clean();
+ cgi_init();
+ start();
+}
+
+# This is the mod_perl handler.
+sub handler {
+ require Apache::Constants;
+ clean();
+ if (my $ret = mod_perl_init(shift)) {
+ return $ret;
+ }
+ start();
+ no strict 'subs';
+ return Apache::Constants::OK();
}
1;
+=head1 NAME
+
+PLP - Perl in HTML pages
+
+=head1 SYNOPSIS
+
+=head2 mod_perl installation
+
+=over 10
+
+=item * httpd.conf (for mod_perl setup)
+
+ <Files *.plp>
+ SetHandler perl-script
+ PerlHandler PLP
+ PerlSendHeader On
+ </Files>
+
+ # Who said CGI was easier to set up? :)
+
+=back
+
+=head2 CGI installation
+
+=over 10
+
+=item * /foo/bar/plp.cgi (local filesystem address)
+
+ #!/usr/bin/perl
+ use PLP;
+ PLP::everything();
+
+=item * httpd.conf (for CGI setup)
+
+ ScriptAlias /foo/bar/ /PLP_COMMON/
+ <Directory /foo/bar/>
+ AllowOverride None
+ Options +ExecCGI
+ Order allow,deny
+ Allow from all
+ </Directory>
+ AddHandler plp-document plp
+ Action plp-document /PLP_COMMON/plp.cgi
+
+=back
+
+=head2 Test script (test.plp)
+
+ <html><body>
+ <:
+ print "Hurrah, it works!<br>" for 1..10;
+ :>
+ </body></html>
+
+=head1 DESCRIPTION
+
+PLP is yet another Perl embedder, primarily for HTML documents. Unlike with
+other Perl embedders, there is no need to learn a meta-syntax or object
+model: one can just use the normal Perl constructs. PLP runs under mod_perl
+for speeds comparable to those of PHP, but can also be run as a CGI script.
+
+=head2 PLP Syntax
+
+=over 22
+
+=item C<< <: perl_code(); :> >>
+
+With C<< <: >> and C<< :> >>, you can add Perl code to your document. This is
+what PLP is all about. All code outside of these tags is printed. It is
+possible to mix perl language constructs with normal HTML parts of the document:
+
+ <: unless ($ENV{REMOTE_USER}) { :>
+ You are not logged in.
+ <: } :>
+
+C<< :> >> always stops a code block, even when it is found in a string literal.
+
+=item C<< <:= $expression :> >>
+
+Includes a dynamic expression in your document. The expression is evaluated in
+list context. Please note that the expression should not end a statement: avoid
+semi-colons. No whitespace may be between C<< <: >> and the equal sign.
+
+C<< foo <:= $bar :> $baz >> is like C<< <: print 'foo ', $bar, ' baz'; :> >>.
+
+=item C<< <(filename)> >>
+
+Includes another file before the PLP code is executed. The file is included
+literally, so it shares lexical variables. Because this is a compile-time tag,
+it's fast, but you can't use a variable as the filename. You can create
+recursive includes, so beware of that! Whitespace in the filename is not
+ignored so C<< <( foo.txt)> >> includes the file named C< foo.txt>, including
+the space in its name. A compile-time alternative is include(), which is
+described in L<PLP::Functions>.
+
+=back
+
+=head2 PLP Functions
+
+These are described in L<PLP::Functions>.
+
+=head2 PLP Variables
+
+=over 22
+
+=item $ENV{PLP_NAME}
+
+The URI of the PLP document, without the query string. (Example: C</foo.plp>)
+
+=item $ENV{PLP_FILENAME}
+
+The filename of the PLP document. (Example: C</var/www/index.plp>)
+
+=item $PLP::VERSION
+
+The version of PLP.
+
+=item $PLP::DEBUG
+
+Controls debugging output, and should be treated as a bitmask. The least
+significant bit (1) controls if run-time error messages are reported to the
+browser, the second bit (2) controls if headers are sent twice, so they get
+displayed in the browser. A value of 3 means both features are enabled. The
+default value is 1.
+
+=item $PLP::ERROR
+
+Contains a reference to the code that is used to report run-time errors. You
+can override this to have it in your own design, and you could even make it
+report errors by e-mail. The sub reference gets two arguments: the error message
+as plain text and the error message with special characters encoded with HTML
+entities.
+
+=item %header, %cookie, %get, %post, %fields
+
+These are described in L<PLP::Fields>.
+
+=back
+
+=head2 Things that you should know about
+
+Not only syntax is important, you should also be aware of some other important
+features. Your script runs inside the package C<PLP::Script> and shouldn't
+leave it. This is because when your script ends, all global variables in the
+C<PLP::Script> package are destroyed, which is very important if you run under
+mod_perl (they would retain their values if they weren't explicitly destroyed).
+
+Until your first output, you are printing to a tied filehandle C<PLPOUT>. On
+first output, headers are sent to the browser and C<STDOUT> is selected for
+efficiency. To set headers, you must assign to C<$header{ $header_name}> before
+any output. This means the opening C<< <: >> have to be the first characters in
+your document, without any whitespace in front of them. If you start output and
+try to set headers later, an error message will appear telling you on which
+line your output started.
+
+Because the interpreter that mod_perl uses never ends, C<END { }> blocks won't
+work properly. You should use C<PLP_END { };> instead. Note that this is a not
+a built-in construct, so it needs proper termination with a semi-colon (as do
+<eval> and <do>).
+
+Under mod_perl, modules are loaded only once. A good modular design can improve
+performance because of this, but you will have to B<reload> the modules
+yourself when there are newer versions.
+
+The special hashes are tied hashes and do not always behave the way you expect,
+especially when mixed with modules that expect normal CGI environments, like
+CGI.pm. Read L<PLP::Fields> for information more about this.
+
+=head1 WEBSITE
+
+For now, all documentation is on the website. Everything will be POD one day,
+but until that day, you will need to visit http://plp.juerd.nl/
+
+=head1 FAQ
+
+A lot of questions are asked often, so before asking yours, please read the
+FAQ at L<PLP::FAQ>.
+
+=head1 NO WARRANTY
+
+No warranty, no guarantees. Use PLP at your own risk, as I disclaim all
+responsibility.
+
+=head1 AUTHOR
+
+Juerd Waalboer <juerd@juerd.nl>
+
+=cut
+