methods/server.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 /* ######################################################################
   4
   5    Classes dealing with the abstraction of talking to a end via a text
   6    protocol like HTTP (which is used by the http and https methods)
   7
   8    ##################################################################### */
   9                                                                         /*}}}*/
  10
  11 #ifndef APT_SERVER_H
  12 #define APT_SERVER_H
  13
  14 #include <apt-pkg/strutl.h>
  15 #include <apt-pkg/fileutl.h>
  16 #include "aptmethod.h"
  17
  18 #include <time.h>
  19 #include <iostream>
  20 #include <string>
  21 #include <memory>
  22
  23 using std::cout;
  24 using std::endl;
  25
  26 class Hashes;
  27 class ServerMethod;
  28 struct ServerState;
  29
  30 struct RequestState
  31 {
  32    unsigned int Major = 0;
  33    unsigned int Minor = 0;
  34    unsigned int Result = 0;
  35    char Code[360];
  36
  37    // total size of the usable content (aka: the file)
  38    unsigned long long TotalFileSize = 0;
  39    // size we actually download (can be smaller than Size if we have partial content)
  40    unsigned long long DownloadSize = 0;
  41    // size of junk content (aka: server error pages)
  42    unsigned long long JunkSize = 0;
  43    // The start of the data (for partial content)
  44    unsigned long long StartPos = 0;
  45
  46    unsigned long long MaximumSize = 0;
  47
  48    time_t Date;
  49    bool HaveContent = false;
  50    enum {Chunked,Stream,Closes} Encoding = Closes;
  51    enum {Header, Data} State = Header;
  52    std::string Location;
  53
  54    FileFd File;
  55
  56    ServerMethod * const Owner;
  57    ServerState * const Server;
  58
  59    bool HeaderLine(std::string const &Line);
  60    bool AddPartialFileToHashes(FileFd &File);
  61
  62    RequestState(ServerMethod * const Owner, ServerState * const Server) :
  63       Owner(Owner), Server(Server) { time(&Date); }
  64 };
  65
  66 struct ServerState
  67 {
  68    bool Persistent;
  69    bool PipelineAllowed;
  70    bool RangesAllowed;
  71
  72    bool Pipeline;
  73    URI ServerName;
  74    URI Proxy;
  75    unsigned long TimeOut;
  76
  77    protected:
  78    ServerMethod *Owner;
  79
  80    virtual bool ReadHeaderLines(std::string &Data) = 0;
  81    virtual bool LoadNextResponse(bool const ToFile, RequestState &Req) = 0;
  82
  83    public:
  84
  85    /** \brief Result of the header acquire */
  86    enum RunHeadersResult {
  87       /** \brief Header ok */
  88       RUN_HEADERS_OK,
  89       /** \brief IO error while retrieving */
  90       RUN_HEADERS_IO_ERROR,
  91       /** \brief Parse error after retrieving */
  92       RUN_HEADERS_PARSE_ERROR
  93    };
  94    /** \brief Get the headers before the data */
  95    RunHeadersResult RunHeaders(RequestState &Req, const std::string &Uri);
  96
  97    bool Comp(URI Other) const {return Other.Host == ServerName.Host && Other.Port == ServerName.Port;};
  98    virtual void Reset();
  99    virtual bool WriteResponse(std::string const &Data) = 0;
 100
 101    /** \brief Transfer the data from the socket */
 102    virtual bool RunData(RequestState &Req) = 0;
 103    virtual bool RunDataToDevNull(RequestState &Req) = 0;
 104
 105    virtual bool Open() = 0;
 106    virtual bool IsOpen() = 0;
 107    virtual bool Close() = 0;
 108    virtual bool InitHashes(HashStringList const &ExpectedHashes) = 0;
 109    virtual bool Die(RequestState &Req) = 0;
 110    virtual bool Flush(FileFd * const File) = 0;
 111    virtual bool Go(bool ToFile, RequestState &Req) = 0;
 112    virtual Hashes * GetHashes() = 0;
 113
 114    ServerState(URI Srv, ServerMethod *Owner);
 115    virtual ~ServerState() {};
 116 };
 117
 118 class ServerMethod : public aptMethod
 119 {
 120    protected:
 121    virtual bool Fetch(FetchItem *) APT_OVERRIDE;
 122
 123    std::unique_ptr<ServerState> Server;
 124    std::string NextURI;
 125
 126    unsigned long PipelineDepth;
 127    bool AllowRedirect;
 128
 129    // Find the biggest item in the fetch queue for the checking of the maximum
 130    // size
 131    unsigned long long FindMaximumObjectSizeInQueue() const APT_PURE;
 132
 133    public:
 134    bool Debug;
 135
 136    /** \brief Result of the header parsing */
 137    enum DealWithHeadersResult {
 138       /** \brief The file is open and ready */
 139       FILE_IS_OPEN,
 140       /** \brief We got a IMS hit, the file has not changed */
 141       IMS_HIT,
 142       /** \brief The server reported a unrecoverable error */
 143       ERROR_UNRECOVERABLE,
 144       /** \brief The server reported a error with a error content page */
 145       ERROR_WITH_CONTENT_PAGE,
 146       /** \brief An error on the client side */
 147       ERROR_NOT_FROM_SERVER,
 148       /** \brief A redirect or retry request */
 149       TRY_AGAIN_OR_REDIRECT
 150    };
 151    /** \brief Handle the retrieved header data */
 152    virtual DealWithHeadersResult DealWithHeaders(FetchResult &Res, RequestState &Req);
 153
 154    // In the event of a fatal signal this file will be closed and timestamped.
 155    static std::string FailFile;
 156    static int FailFd;
 157    static time_t FailTime;
 158    static APT_NORETURN void SigTerm(int);
 159
 160    int Loop();
 161
 162    virtual void SendReq(FetchItem *Itm) = 0;
 163    virtual std::unique_ptr<ServerState> CreateServerState(URI const &uri) = 0;
 164    virtual void RotateDNS() = 0;
 165    virtual bool Configuration(std::string Message) APT_OVERRIDE;
 166
 167    bool AddProxyAuth(URI &Proxy, URI const &Server) const;
 168
 169    ServerMethod(std::string &&Binary, char const * const Ver,unsigned long const Flags);
 170    virtual ~ServerMethod() {};
 171 };
 172
 173 #endif