xbmc/utils/HttpParser.h

   1 /*
   2  *  Copyright (C) 2011-2018 Team Kodi
   3  *  This file is part of Kodi - https://kodi.tv
   4  *
   5  *  SPDX-License-Identifier: GPL-2.0-or-later
   6  *  See LICENSES/README.md for more information.
   7  *
   8  *  This code implements parsing of HTTP requests.
   9  *  This code was written by Steve Hanov in 2009, no copyright is claimed.
  10  *  This code is in the public domain.
  11  *  Code was taken from http://refactormycode.com/codes/778-an-efficient-http-parser
  12  */
  13
  14 #pragma once
  15
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <string>
  19 #include <vector>
  20
  21 // A class to incrementally parse an HTTP header as it comes in. It
  22 // lets you know when it has received all required bytes, as specified
  23 // by the content-length header (if present). If there is no content-length,
  24 // it will stop reading after the final "\n\r".
  25 //
  26 // Example usage:
  27 //
  28 //    HttpParser parser;
  29 //    HttpParser::status_t status;
  30 //
  31 //    for( ;; ) {
  32 //        // read bytes from socket into buffer, break on error
  33 //        status = parser.addBytes( buffer, length );
  34 //        if ( status != HttpParser::Incomplete ) break;
  35 //    }
  36 //
  37 //    if ( status == HttpParser::Done ) {
  38 //        // parse fully formed http message.
  39 //    }
  40
  41
  42 class HttpParser
  43 {
  44 public:
  45     ~HttpParser();
  46
  47     enum status_t {
  48         Done,
  49         Error,
  50         Incomplete
  51     };
  52
  53     status_t addBytes( const char* bytes, unsigned len );
  54
  55     const char* getMethod() const;
  56     const char* getUri() const;
  57     const char* getQueryString() const;
  58     const char* getBody() const;
  59     // key should be in lower case when looking up.
  60     const char* getValue( const char* key ) const;
  61     unsigned getContentLength() const;
  62
  63 private:
  64     void parseHeader();
  65     bool parseRequestLine();
  66
  67     std::string _data;
  68     unsigned _headerStart = 0;
  69     unsigned _parsedTo =  0 ;
  70     int _state =  0 ;
  71     unsigned _keyIndex = 0;
  72     unsigned _valueIndex = 0;
  73     unsigned _contentLength = 0;
  74     unsigned _contentStart = 0;
  75     unsigned _uriIndex = 0;
  76
  77     typedef std::vector<unsigned> IntArray;
  78     IntArray _keys;
  79
  80     enum State {
  81         p_request_line=0,
  82         p_request_line_cr=1,
  83         p_request_line_crlf=2,
  84         p_request_line_crlfcr=3,
  85         p_key=4,
  86         p_key_colon=5,
  87         p_key_colon_sp=6,
  88         p_value=7,
  89         p_value_cr=8,
  90         p_value_crlf=9,
  91         p_value_crlfcr=10,
  92         p_content=11, // here we are done parsing the header.
  93         p_error=12 // here an error has occurred and the parse failed.
  94     };
  95
  96     status_t _status =  Incomplete ;
  97 };
  98