<?php
final class AphrontMultipartParser extends Phobject {
private $contentType;
private $boundary;
private $buffer;
private $body;
private $state;
private $part;
private $parts;
public function setContentType($content_type) {
$this->contentType = $content_type;
return $this;
}
public function getContentType() {
return $this->contentType;
}
public function beginParse() {
$content_type = $this->getContentType();
if ($content_type === null) {
throw new PhutilInvalidStateException('setContentType');
}
if (!preg_match('(^multipart/form-data)', $content_type)) {
throw new Exception(
pht(
'Expected "multipart/form-data" content type when executing a '.
'multipart body read.'));
}
$type_parts = preg_split('(\s*;\s*)', $content_type);
$boundary = null;
foreach ($type_parts as $type_part) {
$matches = null;
if (preg_match('(^boundary=(.*))', $type_part, $matches)) {
$boundary = $matches[1];
break;
}
}
if ($boundary === null) {
throw new Exception(
pht('Received "multipart/form-data" request with no "boundary".'));
}
$this->parts = array();
$this->part = null;
$this->buffer = '';
$this->boundary = $boundary;
// We're looking for a (usually empty) body before the first boundary.
$this->state = 'bodynewline';
}
public function continueParse($bytes) {
$this->buffer .= $bytes;
$continue = true;
while ($continue) {
switch ($this->state) {
case 'endboundary':
// We've just parsed a boundary. Next, we expect either "--" (which
// indicates we've reached the end of the parts) or "\r\n" (which
// indicates we should read the headers for the next part).
if (strlen($this->buffer) < 2) {
// We don't have enough bytes yet, so wait for more.
$continue = false;
break;
}
if (!strncmp($this->buffer, '--', 2)) {
// This is "--" after a boundary, so we're done. We'll read the
// rest of the body (the "epilogue") and discard it.
$this->buffer = substr($this->buffer, 2);
$this->state = 'epilogue';
$this->part = null;
break;
}
if (!strncmp($this->buffer, "\r\n", 2)) {
// This is "\r\n" after a boundary, so we're going to going to
// read the headers for a part.
$this->buffer = substr($this->buffer, 2);
$this->state = 'header';
// Create the object to hold the part we're about to read.
$part = new AphrontMultipartPart();
$this->parts[] = $part;
$this->part = $part;
break;
}
throw new Exception(
pht('Expected "\r\n" or "--" after multipart data boundary.'));
case 'header':
// We've just parsed a boundary, followed by "\r\n". We are going
// to read the headers for this part. They are in the form of HTTP
// headers and terminated by "\r\n". The section is terminated by
// a line with no header on it.
if (strlen($this->buffer) < 2) {
// We don't have enough data to find a "\r\n", so wait for more.
$continue = false;
break;
}
if (!strncmp("\r\n", $this->buffer, 2)) {
// This line immediately began "\r\n", so we're done with parsing
// headers. Start parsing the body.
$this->buffer = substr($this->buffer, 2);
$this->state = 'body';
break;
}
// This is an actual header, so look for the end of it.
$header_len = strpos($this->buffer, "\r\n");
if ($header_len === false) {
// We don't have a full header yet, so wait for more data.
$continue = false;
break;
}
$header_buf = substr($this->buffer, 0, $header_len);
$this->part->appendRawHeader($header_buf);
$this->buffer = substr($this->buffer, $header_len + 2);
break;
case 'body':
// We've parsed a boundary and headers, and are parsing the data for
// this part. The data is terminated by "\r\n--", then the boundary.
// We'll look for "\r\n", then switch to the "bodynewline" state if
// we find it.
$marker = "\r";
$marker_pos = strpos($this->buffer, $marker);
if ($marker_pos === false) {
// There's no "\r" anywhere in the buffer, so we can just read it
// as provided. Then, since we read all the data, we're done until
// we get more.
// Note that if we're in the preamble, we won't have a "part"
// object and will just discard the data.
if ($this->part) {
$this->part->appendData($this->buffer);
}
$this->buffer = '';
$continue = false;
break;
}
if ($marker_pos > 0) {
// If there are bytes before the "\r",
if ($this->part) {
$this->part->appendData(substr($this->buffer, 0, $marker_pos));
}
$this->buffer = substr($this->buffer, $marker_pos);
}
$expect = "\r\n";
$expect_len = strlen($expect);
if (strlen($this->buffer) < $expect_len) {
// We don't have enough bytes yet to know if this is "\r\n"
// or not.
$continue = false;
break;
}
if (strncmp($this->buffer, $expect, $expect_len)) {
// The next two bytes aren't "\r\n", so eat them and go looking
// for more newlines.
if ($this->part) {
$this->part->appendData(substr($this->buffer, 0, $expect_len));
}
$this->buffer = substr($this->buffer, $expect_len);
break;
}
// Eat the "\r\n".
$this->buffer = substr($this->buffer, $expect_len);
$this->state = 'bodynewline';
break;
case 'bodynewline':
// We've parsed a newline in a body, or we just started parsing the
// request. In either case, we're looking for "--", then the boundary.
// If we find it, this section is done. If we don't, we consume the
// bytes and move on.
$expect = '--'.$this->boundary;
$expect_len = strlen($expect);
if (strlen($this->buffer) < $expect_len) {
// We don't have enough bytes yet, so wait for more.
$continue = false;
break;
}
if (strncmp($this->buffer, $expect, $expect_len)) {
// This wasn't the boundary, so return to the "body" state and
// consume it. (But first, we need to append the "\r\n" which we
// ate earlier.)
if ($this->part) {
$this->part->appendData("\r\n");
}
$this->state = 'body';
break;
}
// This is the boundary, so toss it and move on.
$this->buffer = substr($this->buffer, $expect_len);
$this->state = 'endboundary';
break;
case 'epilogue':
// We just discard any epilogue.
$this->buffer = '';
$continue = false;
break;
default:
throw new Exception(
pht(
'Unknown parser state "%s".\n',
$this->state));
}
}
}
public function endParse() {
if ($this->state !== 'epilogue') {
throw new Exception(
pht(
'Expected "multipart/form-data" parse to end '.
'in state "epilogue".'));
}
return $this->parts;
}
}