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; // size of the usable content (aka: the file)
  38    unsigned long long JunkSize; // size of junk content (aka: server error pages)
  39    unsigned long long StartPos;
  40    time_t Date;
  41    bool HaveContent;
  42    enum {Chunked,Stream,Closes} Encoding;
  43    enum {Header, Data} State;
  44    bool Persistent;
  45    std::string Location;
  46
  47    // This is a Persistent attribute of the server itself.
  48    bool Pipeline;
  49    URI ServerName;
  50    URI Proxy;
  51    unsigned long TimeOut;
  52
  53    unsigned long long MaximumSize;
  54
  55    protected:
  56    ServerMethod *Owner;
  57
  58    virtual bool ReadHeaderLines(std::string &Data) = 0;
  59    virtual bool LoadNextResponse(bool const ToFile, FileFd * const File) = 0;
  60
  61    public:
  62    bool HeaderLine(std::string Line);
  63
  64    /** \brief Result of the header acquire */
  65    enum RunHeadersResult {
  66       /** \brief Header ok */
  67       RUN_HEADERS_OK,
  68       /** \brief IO error while retrieving */
  69       RUN_HEADERS_IO_ERROR,
  70       /** \brief Parse error after retrieving */
  71       RUN_HEADERS_PARSE_ERROR
  72    };
  73    /** \brief Get the headers before the data */
  74    RunHeadersResult RunHeaders(FileFd * const File, const std::string &Uri);
  75
  76    bool Comp(URI Other) const {return Other.Host == ServerName.Host && Other.Port == ServerName.Port;};
  77    virtual void Reset() {Major = 0; Minor = 0; Result = 0; Code[0] = '\0'; Size = 0; JunkSize = 0;
  78                  StartPos = 0; Encoding = Closes; time(&Date); HaveContent = false;
  79                  State = Header; Persistent = false; Pipeline = true; MaximumSize = 0;};
  80    virtual bool WriteResponse(std::string const &Data) = 0;
  81
  82    /** \brief Transfer the data from the socket */
  83    virtual bool RunData(FileFd * const File) = 0;
  84
  85    virtual bool Open() = 0;
  86    virtual bool IsOpen() = 0;
  87    virtual bool Close() = 0;
  88    virtual bool InitHashes(FileFd &File) = 0;
  89    virtual Hashes * GetHashes() = 0;
  90    virtual bool Die(FileFd &File) = 0;
  91    virtual bool Flush(FileFd * const File) = 0;
  92    virtual bool Go(bool ToFile, FileFd * const File) = 0;
  93
  94    ServerState(URI Srv, ServerMethod *Owner);
  95    virtual ~ServerState() {};
  96 };
  97
  98 class ServerMethod : public pkgAcqMethod
  99 {
 100    protected:
 101    virtual bool Fetch(FetchItem *);
 102
 103    ServerState *Server;
 104    std::string NextURI;
 105    FileFd *File;
 106
 107    unsigned long PipelineDepth;
 108    bool AllowRedirect;
 109
 110    // Find the biggest item in the fetch queue for the checking of the maximum
 111    // size
 112    unsigned long long FindMaximumObjectSizeInQueue() const APT_PURE;
 113
 114    public:
 115    bool Debug;
 116
 117    /** \brief Result of the header parsing */
 118    enum DealWithHeadersResult {
 119       /** \brief The file is open and ready */
 120       FILE_IS_OPEN,
 121       /** \brief We got a IMS hit, the file has not changed */
 122       IMS_HIT,
 123       /** \brief The server reported a unrecoverable error */
 124       ERROR_UNRECOVERABLE,
 125       /** \brief The server reported a error with a error content page */
 126       ERROR_WITH_CONTENT_PAGE,
 127       /** \brief An error on the client side */
 128       ERROR_NOT_FROM_SERVER,
 129       /** \brief A redirect or retry request */
 130       TRY_AGAIN_OR_REDIRECT
 131    };
 132    /** \brief Handle the retrieved header data */
 133    DealWithHeadersResult DealWithHeaders(FetchResult &Res);
 134
 135    // In the event of a fatal signal this file will be closed and timestamped.
 136    static std::string FailFile;
 137    static int FailFd;
 138    static time_t FailTime;
 139    static APT_NORETURN void SigTerm(int);
 140
 141    virtual bool Configuration(std::string Message);
 142    virtual bool Flush() { return Server->Flush(File); };
 143
 144    int Loop();
 145
 146    virtual void SendReq(FetchItem *Itm) = 0;
 147    virtual ServerState * CreateServerState(URI uri) = 0;
 148    virtual void RotateDNS() = 0;
 149
 150    ServerMethod(const char *Ver,unsigned long Flags = 0) : pkgAcqMethod(Ver, Flags), Server(NULL), File(NULL), PipelineDepth(10), AllowRedirect(false), Debug(false) {};
 151    virtual ~ServerMethod() {};
 152 };
 153
 154 #endif