src/store/LocalSearch.cc

   1 /*
   2  * Copyright (C) 1996-2020 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 /* DEBUG: section 47    Store Search */
  10
  11 #include "squid.h"
  12 #include "Debug.h"
  13 #include "globals.h"
  14 #include "store/LocalSearch.h"
  15 #include "StoreSearch.h"
  16
  17 namespace Store {
  18
  19 /// iterates local store_table
  20 class LocalSearch : public StoreSearch
  21 {
  22     CBDATA_CLASS(LocalSearch);
  23
  24 public:
  25     /* StoreSearch API */
  26     virtual void next(void (callback)(void *cbdata), void *cbdata) override;
  27     virtual bool next() override;
  28     virtual bool error() const override;
  29     virtual bool isDone() const override;
  30     virtual StoreEntry *currentItem() override;
  31
  32 private:
  33     void copyBucket();
  34     bool _done = false;
  35     int bucket = 0;
  36     std::vector<StoreEntry *> entries;
  37 };
  38
  39 } // namespace Store
  40
  41 CBDATA_NAMESPACED_CLASS_INIT(Store, LocalSearch);
  42
  43 StoreSearch *
  44 Store::NewLocalSearch()
  45 {
  46     return new LocalSearch;
  47 }
  48
  49 void
  50 Store::LocalSearch::next(void (aCallback)(void *), void *aCallbackData)
  51 {
  52     next();
  53     aCallback (aCallbackData);
  54 }
  55
  56 bool
  57 Store::LocalSearch::next()
  58 {
  59     if (!entries.empty())
  60         entries.pop_back();
  61
  62     while (!isDone() && !entries.size())
  63         copyBucket();
  64
  65     return currentItem() != NULL;
  66 }
  67
  68 bool
  69 Store::LocalSearch::error() const
  70 {
  71     return false;
  72 }
  73
  74 bool
  75 Store::LocalSearch::isDone() const
  76 {
  77     return bucket >= store_hash_buckets || _done;
  78 }
  79
  80 StoreEntry *
  81 Store::LocalSearch::currentItem()
  82 {
  83     if (!entries.size())
  84         return NULL;
  85
  86     return entries.back();
  87 }
  88
  89 void
  90 Store::LocalSearch::copyBucket()
  91 {
  92     /* probably need to lock the store entries...
  93      * we copy them all to prevent races on the links. */
  94     debugs(47, 3, "Store::LocalSearch::copyBucket #" << bucket);
  95     assert (!entries.size());
  96     hash_link *link_ptr = NULL;
  97     hash_link *link_next = NULL;
  98     link_next = hash_get_bucket(store_table, bucket);
  99
 100     while (NULL != (link_ptr = link_next)) {
 101         link_next = link_ptr->next;
 102         StoreEntry *e = (StoreEntry *) link_ptr;
 103
 104         entries.push_back(e);
 105     }
 106
 107     ++bucket;
 108     debugs(47,3, "got entries: " << entries.size());
 109 }
 110