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