XRootD
XrdPosixPrepIO.cc
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1 /******************************************************************************/
2 /* */
3 /* X r d P o s i x P r e p I O . c c */
4 /* */
5 /* (c) 2016 by the Board of Trustees of the Leland Stanford, Jr., University */
6 /* All Rights Reserved */
7 /* Produced by Andrew Hanushevsky for Stanford University under contract */
8 /* DE-AC02-76-SFO0515 with the Department of Energy */
9 /* */
10 /* This file is part of the XRootD software suite. */
11 /* */
12 /* XRootD is free software: you can redistribute it and/or modify it under */
13 /* the terms of the GNU Lesser General Public License as published by the */
14 /* Free Software Foundation, either version 3 of the License, or (at your */
15 /* option) any later version. */
16 /* */
17 /* XRootD is distributed in the hope that it will be useful, but WITHOUT */
18 /* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or */
19 /* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public */
20 /* License for more details. */
21 /* */
22 /* You should have received a copy of the GNU Lesser General Public License */
23 /* along with XRootD in a file called COPYING.LESSER (LGPL license) and file */
24 /* COPYING (GPL license). If not, see <http://www.gnu.org/licenses/>. */
25 /* */
26 /* The copyright holder's institutional names and contributor's names may not */
27 /* be used to endorse or promote products derived from this software without */
28 /* specific prior written permission of the institution or contributor. */
29 /******************************************************************************/
30 
35 
36 /******************************************************************************/
37 /* G l o b a l s */
38 /******************************************************************************/
39 
40 namespace XrdPosixGlobals
41 {
42 extern XrdOucCache *theCache;
43 extern XrdPosixStats Stats;
44 };
45 
46 /******************************************************************************/
47 /* D i s a b l e */
48 /******************************************************************************/
49 
51 {
52  EPNAME("PrepIODisable");
53  XrdPosixObjGuard objGuard(fileP);
54 
55  DEBUG("Disabling deferred open "<<fileP->Origin());
56 
57  openRC = -ESHUTDOWN;
58 }
59 
60 /******************************************************************************/
61 /* I n i t */
62 /******************************************************************************/
63 
64 bool XrdPosixPrepIO::Init(XrdOucCacheIOCB *iocbP)
65 {
66  EPNAME("PrepIOInit");
67  XrdPosixObjGuard objGuard(fileP);
68  XrdCl::XRootDStatus Status;
69  static int maxCalls = 64;
70 
71 // Count the number of entries here. We want to catch someone ignoring the
72 // Update() call and using this object as it is very ineffecient.
73 //
74  if (iCalls++ >= maxCalls)
75  {maxCalls = maxCalls*2;
76  DMSG("Init", iCalls <<" unexpected PrepIO calls!");
77  }
78 
79 // Do not try to open the file if there was previous error
80 //
81  if (openRC) return false;
82 
83 // Check if the file is already opened. This caller may be vestigial
84 //
85  if (fileP->clFile.IsOpen()) return true;
86 
87 // Count number of opens after the open was deferred (successful or not)
88 //
91  (XrdPosixGlobals::theCache->Statistics.X.OpenDefers));
92 
93 // Open the file. It is too difficult to do an async open here as there is a
94 // possible pending async request and doing both is not easy at all.
95 //
96  Status = fileP->clFile.Open((std::string)fileP->Origin(), clFlags, clMode);
98 
99 // Make sure all went well. If so, do a Stat() call on the underlying file
100 //
101  if (Status.IsOK()) fileP->Stat(Status);
102  else {openRC = XrdPosixMap::Result(Status, fileP->ecMsg, false);
103  if (DEBUGON && errno != ENOENT && errno != ELOOP)
104  {std::string eTxt = Status.ToString();
105  DEBUG(eTxt<<" deferred open "<<fileP->Origin());
106  }
108  return false;
109  }
110 
111 // Inform the cache that we have now have a new I/O object
112 //
113  fileP->XCio->Update(*fileP);
114  return true;
115 }
#define DEBUG(x)
Definition: XrdBwmTrace.hh:54
#define EPNAME(x)
Definition: XrdBwmTrace.hh:56
#define DMSG(x, y)
#define DEBUGON
bool IsOpen() const
Check if the file is open.
Definition: XrdClFile.cc:846
XRootDStatus Open(const std::string &url, OpenFlags::Flags flags, Access::Mode mode, ResponseHandler *handler, uint16_t timeout=0) XRD_WARN_UNUSED_RESULT
Definition: XrdClFile.cc:99
virtual void Update(XrdOucCacheIO &iocp)
Definition: XrdOucCache.hh:418
void Count(long long &Dest)
XrdOucCacheStats Statistics
Definition: XrdOucCache.hh:686
const char * Origin()
bool Stat(XrdCl::XRootDStatus &Status, bool force=false)
XrdCl::File clFile
Definition: XrdPosixFile.hh:67
XrdOucCacheIO * XCio
Definition: XrdPosixFile.hh:65
static int Result(const XrdCl::XRootDStatus &Status, XrdOucECMsg &ecMsg, bool retneg1=false)
Definition: XrdPosixMap.cc:150
XrdOucECMsg ecMsg
void Count(long long &Dest)
XrdPosixStats Stats
Definition: XrdPosixFile.cc:63
XrdOucCache * theCache
bool IsOK() const
We're fine.
Definition: XrdClStatus.hh:124
std::string ToString() const
Create a string representation.
Definition: XrdClStatus.cc:97