src/PeerDigest.h

   1 /*
   2  * Copyright (C) 1996-2025 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef SQUID_SRC_PEERDIGEST_H
  10 #define SQUID_SRC_PEERDIGEST_H
  11
  12 #if USE_CACHE_DIGESTS
  13
  14 #include "cbdata.h"
  15 #include "StatCounters.h"
  16
  17 class Version
  18 {
  19 public:
  20     short int current;      /* current version */
  21     short int required;     /* minimal version that can safely handle current version */
  22 };
  23
  24 /* digest control block; used for transmission and storage */
  25
  26 class StoreDigestCBlock
  27 {
  28 public:
  29     Version ver;
  30     int capacity;
  31     int count;
  32     int del_count;
  33     int mask_size;
  34     unsigned char bits_per_entry;
  35     unsigned char hash_func_count;
  36     short int reserved_short;
  37     int reserved[32 - 6];
  38 };
  39
  40 class HttpRequest;
  41 class PeerDigest;
  42 class store_client;
  43
  44 class DigestFetchState
  45 {
  46     CBDATA_CLASS(DigestFetchState);
  47
  48 public:
  49     DigestFetchState(PeerDigest *,HttpRequest *);
  50     ~DigestFetchState();
  51
  52     CbcPointer<PeerDigest> pd;
  53     StoreEntry *entry;
  54     StoreEntry *old_entry;
  55     store_client *sc;
  56     store_client *old_sc;
  57     HttpRequest *request;
  58     int offset;
  59     uint32_t mask_offset;
  60     time_t start_time;
  61     time_t resp_time;
  62     time_t expires;
  63
  64     struct {
  65         int msg;
  66         int bytes;
  67     } sent, recv;
  68
  69     char buf[SM_PAGE_SIZE];
  70     ssize_t bufofs;
  71     digest_read_state_t state;
  72 };
  73
  74 class PeerDigest
  75 {
  76     CBDATA_CLASS(PeerDigest);
  77
  78 public:
  79     PeerDigest(CachePeer *);
  80     ~PeerDigest();
  81
  82     /// reacts to digest transfer completion
  83     /// \prec DigestFetchState stats were finalized (by calling peerDigestFetchSetStats())
  84     void noteFetchFinished(const DigestFetchState &, const char *outcomeDescription, bool sawError);
  85
  86     CbcPointer<CachePeer> peer; ///< pointer back to peer structure, argh
  87     CacheDigest *cd = nullptr;            /**< actual digest structure */
  88     const SBuf host; ///< copy of peer->host
  89     const char *req_result = nullptr;     /**< text status of the last request */
  90
  91     struct {
  92         bool needed = false;          /**< there were requests for this digest */
  93         bool usable = false;          /**< can be used for lookups */
  94         bool requested = false;       /**< in process of receiving [fresh] digest */
  95     } flags;
  96
  97     struct {
  98         /* all times are absolute unless augmented with _delay */
  99         time_t initialized = 0; /* creation */
 100         time_t needed = 0;      /* first lookup/use by a peer */
 101         time_t next_check = 0;  /* next scheduled check/refresh event */
 102         time_t retry_delay = 0; /* delay before re-checking _invalid_ digest */
 103         time_t requested = 0;   /* requested a fresh copy of a digest */
 104         time_t req_delay = 0;   /* last request response time */
 105         time_t received = 0;    /* received the current copy of a digest */
 106         time_t disabled = 0;    /* disabled for good */
 107     } times;
 108
 109     struct {
 110         CacheDigestGuessStats guess;
 111         int used_count = 0;
 112
 113         struct {
 114             int msgs = 0;
 115             ByteCounter kbytes;
 116         } sent, recv;
 117     } stats;
 118 };
 119
 120 extern const Version CacheDigestVer;
 121
 122 void peerDigestNeeded(PeerDigest * pd);
 123 void peerDigestNotePeerGone(PeerDigest * pd);
 124 void peerDigestStatsReport(const PeerDigest * pd, StoreEntry * e);
 125
 126 #endif /* USE_CACHE_DIGESTS */
 127
 128 #endif /* SQUID_SRC_PEERDIGEST_H */
 129