src/store_io.cc

   1 /*
   2  * Copyright (C) 1996-2014 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 "SwapDir.h"
  14
  15 StoreIoStats store_io_stats;
  16
  17 /*
  18  * submit a request to create a cache object for writing.
  19  * The StoreEntry structure is sent as a hint to the filesystem
  20  * to what will be stored in this object, to allow the filesystem
  21  * to select different polices depending on object size or type.
  22  */
  23 StoreIOState::Pointer
  24 storeCreate(StoreEntry * e, StoreIOState::STFNCB * file_callback, StoreIOState::STIOCB * close_callback, void *callback_data)
  25 {
  26     assert (e);
  27
  28     ++store_io_stats.create.calls;
  29
  30     /*
  31      * Pick the swapdir
  32      * We assume that the header has been packed by now ..
  33      */
  34     const sdirno dirn = storeDirSelectSwapDir(e);
  35
  36     if (dirn == -1) {
  37         debugs(20, 2, "storeCreate: no swapdirs for " << *e);
  38         ++store_io_stats.create.select_fail;
  39         return NULL;
  40     }
  41
  42     debugs(20, 2, "storeCreate: Selected dir " << dirn << " for " << *e);
  43     SwapDir *SD = dynamic_cast<SwapDir *>(INDEXSD(dirn));
  44
  45     /* Now that we have a fs to use, call its storeCreate function */
  46     StoreIOState::Pointer sio = SD->createStoreIO(*e, file_callback, close_callback, callback_data);
  47
  48     if (sio == NULL)
  49         ++store_io_stats.create.create_fail;
  50     else
  51         ++store_io_stats.create.success;
  52
  53     return sio;
  54 }
  55
  56 /*
  57  * storeOpen() is purely for reading ..
  58  */
  59 StoreIOState::Pointer
  60 storeOpen(StoreEntry * e, StoreIOState::STFNCB * file_callback, StoreIOState::STIOCB * callback,
  61           void *callback_data)
  62 {
  63     return dynamic_cast<SwapDir *>(e->store().getRaw())->openStoreIO(*e, file_callback, callback, callback_data);
  64 }
  65
  66 void
  67 storeClose(StoreIOState::Pointer sio, int how)
  68 {
  69     if (sio->flags.closing) {
  70         debugs(20,3,HERE << "storeClose: flags.closing already set, bailing");
  71         return;
  72     }
  73
  74     sio->flags.closing = true;
  75
  76     debugs(20,3,HERE << "storeClose: calling sio->close(" << how << ")");
  77     sio->close(how);
  78 }
  79
  80 void
  81 storeRead(StoreIOState::Pointer sio, char *buf, size_t size, off_t offset, StoreIOState::STRCB * callback, void *callback_data)
  82 {
  83     sio->read_(buf, size, offset, callback, callback_data);
  84 }
  85
  86 void
  87 storeIOWrite(StoreIOState::Pointer sio, char const *buf, size_t size, off_t offset, FREE * free_func)
  88 {
  89     sio->write(buf,size,offset,free_func);
  90 }