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/acquire-method.h>
  16
  17 #include <time.h>
  18 #include <iostream>
  19 #include <string>
  20
  21 using std::cout;
  22 using std::endl;
  23
  24 class Hashes;
  25 class ServerMethod;
  26 class FileFd;
  27
  28 struct ServerState
  29 {
  30    // This is the last parsed Header Line
  31    unsigned int Major;
  32    unsigned int Minor;
  33    unsigned int Result;
  34    char Code[360];
  35
  36    // These are some statistics from the last parsed header lines
  37    unsigned long long Size; // total size of the usable content (aka: the file)
  38    unsigned long long DownloadSize; // size we actually download (can be smaller than Size if we have partial content)
  39    unsigned long long JunkSize; // size of junk content (aka: server error pages)
  40    unsigned long long StartPos;
  41    time_t Date;
  42    bool HaveContent;
  43    enum {Chunked,Stream,Closes} Encoding;
  44    enum {Header, Data} State;
  45    bool Persistent;
  46    std::string Location;
  47
  48    // This is a Persistent attribute of the server itself.
  49    bool Pipeline;
  50    URI ServerName;
  51    URI Proxy;
  52    unsigned long TimeOut;
  53
  54    protected:
  55    ServerMethod *Owner;
  56
  57    virtual bool ReadHeaderLines(std::string &Data) = 0;
  58    virtual bool LoadNextResponse(bool const ToFile, FileFd * const File) = 0;
  59
  60    public:
  61    bool HeaderLine(std::string Line);
  62
  63    /** \brief Result of the header acquire */
  64    enum RunHeadersResult {
  65       /** \brief Header ok */
  66       RUN_HEADERS_OK,
  67       /** \brief IO error while retrieving */
  68       RUN_HEADERS_IO_ERROR,
  69       /** \brief Parse error after retrieving */
  70       RUN_HEADERS_PARSE_ERROR
  71    };
  72    /** \brief Get the headers before the data */
  73    RunHeadersResult RunHeaders(FileFd * const File, const std::string &Uri);
  74
  75    bool Comp(URI Other) const {return Other.Host == ServerName.Host && Other.Port == ServerName.Port;};
  76    virtual void Reset() {Major = 0; Minor = 0; Result = 0; Code[0] = '\0'; Size = 0; JunkSize = 0;
  77                  StartPos = 0; Encoding = Closes; time(&Date); HaveContent = false;
  78                  State = Header; Persistent = false; Pipeline = true;};
  79    virtual bool WriteResponse(std::string const &Data) = 0;
  80
  81    /** \brief Transfer the data from the socket */
  82    virtual bool RunData(FileFd * const File) = 0;
  83
  84    virtual bool Open() = 0;
  85    virtual bool IsOpen() = 0;
  86    virtual bool Close() = 0;
  87    virtual bool InitHashes(FileFd &File) = 0;
  88    virtual Hashes * GetHashes() = 0;
  89    virtual bool Die(FileFd &File) = 0;
  90    virtual bool Flush(FileFd * const File) = 0;
  91    virtual bool Go(bool ToFile, FileFd * const File) = 0;
  92
  93    ServerState(URI Srv, ServerMethod *Owner);
  94    virtual ~ServerState() {};
  95 };
  96
  97 class ServerMethod : public pkgAcqMethod
  98 {
  99    protected:
 100    virtual bool Fetch(FetchItem *);
 101
 102    ServerState *Server;
 103    std::string NextURI;
 104    FileFd *File;
 105
 106    unsigned long PipelineDepth;
 107    bool AllowRedirect;
 108
 109    public:
 110    bool Debug;
 111
 112    /** \brief Result of the header parsing */
 113    enum DealWithHeadersResult {
 114       /** \brief The file is open and ready */
 115       FILE_IS_OPEN,
 116       /** \brief We got a IMS hit, the file has not changed */
 117       IMS_HIT,
 118       /** \brief The server reported a unrecoverable error */
 119       ERROR_UNRECOVERABLE,
 120       /** \brief The server reported a error with a error content page */
 121       ERROR_WITH_CONTENT_PAGE,
 122       /** \brief An error on the client side */
 123       ERROR_NOT_FROM_SERVER,
 124       /** \brief A redirect or retry request */
 125       TRY_AGAIN_OR_REDIRECT
 126    };
 127    /** \brief Handle the retrieved header data */
 128    DealWithHeadersResult DealWithHeaders(FetchResult &Res);
 129
 130    // In the event of a fatal signal this file will be closed and timestamped.
 131    static std::string FailFile;
 132    static int FailFd;
 133    static time_t FailTime;
 134    static APT_NORETURN void SigTerm(int);
 135
 136    virtual bool Configuration(std::string Message);
 137    virtual bool Flush() { return Server->Flush(File); };
 138
 139    int Loop();
 140
 141    virtual void SendReq(FetchItem *Itm) = 0;
 142    virtual ServerState * CreateServerState(URI uri) = 0;
 143    virtual void RotateDNS() = 0;
 144
 145    ServerMethod(const char *Ver,unsigned long Flags = 0) : pkgAcqMethod(Ver, Flags), Server(NULL), File(NULL), PipelineDepth(0), AllowRedirect(false), Debug(false) {};
 146    virtual ~ServerMethod() {};
 147 };
 148
 149 #endif