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
  38    // total size of the usable content (aka: the file)
  39    unsigned long long TotalFileSize;
  40    // size we actually download (can be smaller than Size if we have partial content)
  41    unsigned long long DownloadSize;
  42    // size of junk content (aka: server error pages)
  43    unsigned long long JunkSize;
  44    // The start of the data (for partial content)
  45    unsigned long long StartPos;
  46
  47    time_t Date;
  48    bool HaveContent;
  49    enum {Chunked,Stream,Closes} Encoding;
  50    enum {Header, Data} State;
  51    bool Persistent;
  52    std::string Location;
  53
  54    // This is a Persistent attribute of the server itself.
  55    bool Pipeline;
  56    URI ServerName;
  57    URI Proxy;
  58    unsigned long TimeOut;
  59
  60    protected:
  61    ServerMethod *Owner;
  62
  63    virtual bool ReadHeaderLines(std::string &Data) = 0;
  64    virtual bool LoadNextResponse(bool const ToFile, FileFd * const File) = 0;
  65
  66    public:
  67    bool HeaderLine(std::string Line);
  68
  69    /** \brief Result of the header acquire */
  70    enum RunHeadersResult {
  71       /** \brief Header ok */
  72       RUN_HEADERS_OK,
  73       /** \brief IO error while retrieving */
  74       RUN_HEADERS_IO_ERROR,
  75       /** \brief Parse error after retrieving */
  76       RUN_HEADERS_PARSE_ERROR
  77    };
  78    /** \brief Get the headers before the data */
  79    RunHeadersResult RunHeaders(FileFd * const File, const std::string &Uri);
  80
  81    bool Comp(URI Other) const {return Other.Host == ServerName.Host && Other.Port == ServerName.Port;};
  82    virtual void Reset() {Major = 0; Minor = 0; Result = 0; Code[0] = '\0'; TotalFileSize = 0; JunkSize = 0;
  83                  StartPos = 0; Encoding = Closes; time(&Date); HaveContent = false;
  84                  State = Header; Persistent = false; Pipeline = true;};
  85    virtual bool WriteResponse(std::string const &Data) = 0;
  86
  87    /** \brief Transfer the data from the socket */
  88    virtual bool RunData(FileFd * const File) = 0;
  89
  90    virtual bool Open() = 0;
  91    virtual bool IsOpen() = 0;
  92    virtual bool Close() = 0;
  93    virtual bool InitHashes(FileFd &File) = 0;
  94    virtual Hashes * GetHashes() = 0;
  95    virtual bool Die(FileFd &File) = 0;
  96    virtual bool Flush(FileFd * const File) = 0;
  97    virtual bool Go(bool ToFile, FileFd * const File) = 0;
  98
  99    ServerState(URI Srv, ServerMethod *Owner);
 100    virtual ~ServerState() {};
 101 };
 102
 103 class ServerMethod : public pkgAcqMethod
 104 {
 105    protected:
 106    virtual bool Fetch(FetchItem *);
 107
 108    ServerState *Server;
 109    std::string NextURI;
 110    FileFd *File;
 111
 112    unsigned long PipelineDepth;
 113    bool AllowRedirect;
 114
 115    public:
 116    bool Debug;
 117
 118    /** \brief Result of the header parsing */
 119    enum DealWithHeadersResult {
 120       /** \brief The file is open and ready */
 121       FILE_IS_OPEN,
 122       /** \brief We got a IMS hit, the file has not changed */
 123       IMS_HIT,
 124       /** \brief The server reported a unrecoverable error */
 125       ERROR_UNRECOVERABLE,
 126       /** \brief The server reported a error with a error content page */
 127       ERROR_WITH_CONTENT_PAGE,
 128       /** \brief An error on the client side */
 129       ERROR_NOT_FROM_SERVER,
 130       /** \brief A redirect or retry request */
 131       TRY_AGAIN_OR_REDIRECT
 132    };
 133    /** \brief Handle the retrieved header data */
 134    DealWithHeadersResult DealWithHeaders(FetchResult &Res);
 135
 136    // In the event of a fatal signal this file will be closed and timestamped.
 137    static std::string FailFile;
 138    static int FailFd;
 139    static time_t FailTime;
 140    static APT_NORETURN void SigTerm(int);
 141
 142    virtual bool Configuration(std::string Message);
 143    virtual bool Flush() { return Server->Flush(File); };
 144
 145    int Loop();
 146
 147    virtual void SendReq(FetchItem *Itm) = 0;
 148    virtual ServerState * CreateServerState(URI uri) = 0;
 149    virtual void RotateDNS() = 0;
 150
 151    ServerMethod(const char *Ver,unsigned long Flags = 0) : pkgAcqMethod(Ver, Flags), Server(NULL), File(NULL), PipelineDepth(0), AllowRedirect(false), Debug(false) {};
 152    virtual ~ServerMethod() {};
 153 };
 154
 155 #endif