src/store_io.cc

   1 /*
   2  * Copyright (C) 1996-2021 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 #include "squid.h"
  10 #include "MemObject.h"
  11 #include "SquidConfig.h"
  12 #include "Store.h"
  13 #include "store/Disk.h"
  14 #include "store/Disks.h"
  15
  16 StoreIoStats store_io_stats;
  17
  18 /*
  19  * submit a request to create a cache object for writing.
  20  * The StoreEntry structure is sent as a hint to the filesystem
  21  * to what will be stored in this object, to allow the filesystem
  22  * to select different polices depending on object size or type.
  23  */
  24 StoreIOState::Pointer
  25 storeCreate(StoreEntry * e, StoreIOState::STFNCB * file_callback, StoreIOState::STIOCB * close_callback, void *callback_data)
  26 {
  27     assert (e);
  28
  29     ++store_io_stats.create.calls;
  30
  31     /*
  32      * Pick the swapdir
  33      * We assume that the header has been packed by now ..
  34      */
  35     const auto sd = Store::Disks::SelectSwapDir(e);
  36
  37     if (!sd) {
  38         debugs(20, 2, "storeCreate: no swapdirs for " << *e);
  39         ++store_io_stats.create.select_fail;
  40         return NULL;
  41     }
  42
  43     /* Now that we have a fs to use, call its storeCreate function */
  44     StoreIOState::Pointer sio = sd->createStoreIO(*e, file_callback, close_callback, callback_data);
  45
  46     if (sio == NULL)
  47         ++store_io_stats.create.create_fail;
  48     else
  49         ++store_io_stats.create.success;
  50
  51     return sio;
  52 }
  53
  54 /*
  55  * storeOpen() is purely for reading ..
  56  */
  57 StoreIOState::Pointer
  58 storeOpen(StoreEntry * e, StoreIOState::STFNCB * file_callback, StoreIOState::STIOCB * callback,
  59           void *callback_data)
  60 {
  61     return e->disk().openStoreIO(*e, file_callback, callback, callback_data);
  62 }
  63
  64 void
  65 storeClose(StoreIOState::Pointer sio, int how)
  66 {
  67     if (sio->flags.closing) {
  68         debugs(20,3,HERE << "storeClose: flags.closing already set, bailing");
  69         return;
  70     }
  71
  72     sio->flags.closing = true;
  73
  74     debugs(20,3,HERE << "storeClose: calling sio->close(" << how << ")");
  75     sio->close(how);
  76 }
  77
  78 void
  79 storeRead(StoreIOState::Pointer sio, char *buf, size_t size, off_t offset, StoreIOState::STRCB * callback, void *callback_data)
  80 {
  81     sio->read_(buf, size, offset, callback, callback_data);
  82 }
  83
  84 void
  85 storeIOWrite(StoreIOState::Pointer sio, char const *buf, size_t size, off_t offset, FREE * free_func)
  86 {
  87     sio->write(buf,size,offset,free_func);
  88 }
  89