/**
* Parses the SRR data and stores a list of valid blocks locally.
*
* @return boolean false if parsing fails
*/
protected function analyze()
{
// Find the SRR MARKER block, or abort if none is found
if (($startPos = $this->findMarker()) === false) {
$this->error = 'Could not find Marker block, not a valid SRR file';
return false;
}
// Start at the SRR MARKER block
$this->seek($startPos);
// Analyze all valid blocks
while ($this->offset < $this->length) {
try {
// Get the next block header
$block = $this->getNextBlock();
// Block type: SRR MARKER
if ($block['head_type'] == self::SRR_BLOCK_MARK) {
if ($block['head_flags'] & self::APP_NAME_PRESENT) {
$block += self::unpack('vapp_name_size', $this->read(2), false);
$block['app_name'] = $this->read($block['app_name_size']);
$this->client = $block['app_name'];
}
if ($block['head_flags'] > 1 || $this->offset != $block['next_offset']) {
$this->error = 'Could not find Marker block, not a valid SRR file';
return false;
}
// Block type: STORED FILE
} elseif ($block['head_type'] == self::SRR_STORED_FILE) {
$block += self::unpack('vname_size', $this->read(2), false);
$block['file_name'] = $this->read($block['name_size']);
$block['file_data'] = $this->read(isset($block['add_size']) ? $block['add_size'] : 0);
// Block type: OSO HASH
} elseif ($block['head_type'] == self::SRR_OSO_HASH) {
$block += self::unpack(self::FORMAT_SRR_OSO_HASH, $this->read(18));
$block['file_hash'] = strrev($block['file_hash']);
$block['file_size'] = self::int64($block['file_size'], $block['file_size_high']);
$block['file_name'] = $this->read($block['name_size']);
// Block type: SRR RAR FILE
} elseif ($block['head_type'] == self::SRR_RAR_FILE) {
$block += self::unpack('vname_size', $this->read(2), false);
$block['file_name'] = $this->read($block['name_size']);
// Default to RAR block processing
} else {
parent::processBlock($block);
}
// Add current block to the list
$this->blocks[] = $block;
// Skip to the next block, if any
if ($this->offset != $block['next_offset']) {
$this->seek($block['next_offset']);
}
// Sanity check
if ($block['offset'] == $this->offset) {
$this->error = 'Parsing seems to be stuck';
$this->close();
return false;
}
// No more readable data, or read error
} catch (Exception $e) {
if ($this->error) {
$this->close();
return false;
}
break;
}
}
// Analysis was successful
return true;
}
