/ 
PHP-Decode-0.302
River stage zero No dependents
/ PHP::Decode::Transformer

NAME

PHP::Decode::Transformer

SYNOPSIS

  # Create an instance

  sub warn_cb {
	my ($ctx, $action, $stmt, $fmt) = (shift, shift, shift, shift);

	my $msg = sprintf $fmt, @_;
	print "WARN: [$ctx->{infunction}] $action $stmt", $msg, "\n";
  }
  my %strmap;
  my $parser = PHP::Decode::Parser->new(strmap => \%strmap);
  my $ctx = PHP::Decode::Transformer->new(parser => $parser, warn => \&warn_cb);

  # Parse and transform php code

  my $str = $parser->setstr('<?php echo "test"; ?>');
  my $blk = $ctx->parse_eval($str);
  my $stmt = $ctx->exec_eval($blk);

  # Expand to code again

  my $code = $parser->format_stmt($stmt);
  print $code;

  # Output: echo 'test' ; $STDOUT = 'test' ;

DESCRIPTION

The PHP::Decode::Transformer Module applies static transformations to PHP statements parsed by the PHP::Decode::Parser module.

METHODS

new

$ctx = PHP::Decode::Transformer->new(parser => $parser);

Create a PHP::Decode::Transformer object. Arguments are passed in key => value pairs.

The only required argument is `parser`.

The new constructor dies when arguments are invalid, or if required arguments are missing.

The accepted arguments are:

warn: optional handler to log transformer warning messages
log: optional handler to log transformer info messages
debug: optional handler to log transformer debug messages
max_loop: optional max iterations for php loop execution (default: 10000)
skip: optional transformer features to skip on execution
$skip->{call}: skip function calls
$skip->{loop}: skip loop execution
$skip->{null}: dont' assume null for undefined vars
$skip->{stdout}: don't include STDOUT
with: optional transformer features to use for execution
$with->{getenv}: eval getenv() for passed enviroment hash
$with->{translate}: translate self-contained funcs to native code (experimental)
$with->{optimize_block_vars}: remove intermediate block vars on toplevel
$with->{invalidate_tainted_vars}: invalidate vars after tainted calls

parse_eval

Parse a php code string.

$stmt = $ctx->parse_eval($str);

The php code string is tokenized and converted to an internal representation of php statements. If a script contains more than one top level statement, the method returns block with a list of these statements.

For more information about the statement types, see the PHP::Decode::Parser Module.

exec_eval

Execute a php statement.

$stmt = $ctx->exec_eval($stmt);

The exec method applies static transformations to the passed php statements, and returns the resulting statements.

subctx

Create sub-class of transformer referencing the global and local varmaps from parent.

$ctx2 = $ctx->subctx(%args);

exec_statement

Execute a php statement and return the result or simplified statement if transformed.

$stmt2 = $ctx->exec_statement($stmt, $in_block);

resolve_variable

Resolve an indexed variable to its basevar and index

($var, $has_idx, $idx) = $ctx->resolve_variable($stmt, $in_block);

- var: resolved variable name (a.e: array name)
- has_idx: is array dereference
- idx: if is array: indexvalue of last index or undef if index is empty

getvar

Get value of a variable

$val = $ctx->getvar($var, $quiet);

setvar

Set value of a variable

$ctx->setvar($var, $val, $in_block);

registerfun

Register a '#fun' definition as callable function

$ctx->registerfun($name, $fun);

getfun

Lookup a user defined function by name

$fun = $ctx->getfun($name);

registerclass

Register a '#class' definition as instantiatable class

$ctx->registerclass($name, $class);

getclass

Lookup a class by name

$class = $ctx->getclass($name);

SEE ALSO

Requires the PHP::Decode::Parser, PHP::Decode::Array and PHP::Decode::Func Modules.

AUTHORS

Barnim Dzwillo @ Strato AG