From 9118903f75457239f23afdf6ed4207fff0a9c559 Mon Sep 17 00:00:00 2001
From: Andrew Hanushevsky <abh@stanford.edu>
Date: Thu, 16 Jun 2016 03:20:10 -0700
Subject: [PATCH] Add Location() method to CacheIO2 to get file location.

---
 src/XrdOuc/XrdOucCache2.hh      |  9 +++++++++
 src/XrdPosix/XrdPosixCacheBC.hh |  3 +++
 src/XrdPosix/XrdPosixFile.cc    | 31 +++++++++++++++++++++++++++++--
 src/XrdPosix/XrdPosixFile.hh    |  5 ++++-
 4 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/src/XrdOuc/XrdOucCache2.hh b/src/XrdOuc/XrdOucCache2.hh
index a27396f5e28..f7487056df1 100644
--- a/src/XrdOuc/XrdOucCache2.hh
+++ b/src/XrdOuc/XrdOucCache2.hh
@@ -76,6 +76,15 @@ public:
 
 virtual int  Fstat(struct stat &sbuff) {(void)sbuff; return 1;}
 
+//-----------------------------------------------------------------------------
+//! Get the file's location (i.e. endpoint hostname and port)
+//!
+//! @return A pointer to the file's location. It remains valid until the file
+//!         is closed. A null string means the file is not open or is unknown.
+//-----------------------------------------------------------------------------
+virtual
+const char  *Location() {return "";}
+
 //------------------------------------------------------------------------------
 //! Perform an asynchronous read (defaults to synchrnous).
 //!
diff --git a/src/XrdPosix/XrdPosixCacheBC.hh b/src/XrdPosix/XrdPosixCacheBC.hh
index 54d05125876..20b65ff88d6 100644
--- a/src/XrdPosix/XrdPosixCacheBC.hh
+++ b/src/XrdPosix/XrdPosixCacheBC.hh
@@ -55,6 +55,9 @@ long long       FSize() {return cacheIO1->FSize();}
 
 virtual int     Fstat(struct stat &buf) {return cacheIO2->Fstat(buf);}
 
+virtual
+const char     *Location() {return cacheIO2->Location();}
+
 virtual
 const char     *Path()  {return cacheIO1->Path();}
 
diff --git a/src/XrdPosix/XrdPosixFile.cc b/src/XrdPosix/XrdPosixFile.cc
index 988af11d8e3..cf245f3f6a7 100644
--- a/src/XrdPosix/XrdPosixFile.cc
+++ b/src/XrdPosix/XrdPosixFile.cc
@@ -59,6 +59,8 @@ pthread_t tid;
 XrdSysThread::Run(&tid, XrdPosixFile::DelayedDestroy, 0, 0, "PosixFileDestroy");
 return (XrdPosixFile *)0;
 }
+
+std::string dsProperty("DataServer");
 };
 
 XrdSysSemaphore XrdPosixFile::ddSem(0);
@@ -77,7 +79,7 @@ XrdPosixFile::XrdPosixFile(const char *path, XrdPosixCallBack *cbP, int Opts)
              : XCio((XrdOucCacheIO2 *)this), PrepIO(0),
                mySize(0), myMtime(0), myInode(0), myMode(0),
                theCB(cbP),
-               fPath(strdup(path)),
+               fPath(strdup(path)), fLoc(0),
                cOpt(0),
                isStream(Opts & isStrm ? 1 : 0)
 {
@@ -113,9 +115,10 @@ XrdPosixFile::~XrdPosixFile()
 //
    if (PrepIO) delete PrepIO;
 
-// Free the path
+// Free the path and location information
 //
    if (fPath) free(fPath);
+   if (fLoc)  free(fLoc);
 }
 
 /******************************************************************************/
@@ -300,6 +303,30 @@ void XrdPosixFile::HandleResponse(XrdCl::XRootDStatus *status,
    if (rc) delete this;
 }
 
+/******************************************************************************/
+/*                              L o c a t i o n                               */
+/******************************************************************************/
+  
+const char *XrdPosixFile::Location()
+{
+
+// If the file is not open, then we have no location
+//
+   if (!clFile.IsOpen()) return 0;
+
+// If we have no location info, get it
+//
+   if (!fLoc)
+      {std::string currNode;
+       if (clFile.GetProperty(dsProperty, currNode))
+          fLoc = strdup(currNode.c_str());
+      }
+
+// Return location information
+//
+   return fLoc;
+}
+
 /******************************************************************************/
 /*                                  R e a d                                   */
 /******************************************************************************/
diff --git a/src/XrdPosix/XrdPosixFile.hh b/src/XrdPosix/XrdPosixFile.hh
index 1f12025494b..6116b147def 100644
--- a/src/XrdPosix/XrdPosixFile.hh
+++ b/src/XrdPosix/XrdPosixFile.hh
@@ -76,7 +76,7 @@ XrdCl::File     clFile;
                                return retOffset;
                               }
 
-static XrdPosixFile *Alloc(const char *path, XrdPosixCallBack *cbP, int Opts);
+//atic XrdPosixFile *Alloc(const char *path, XrdPosixCallBack *cbP, int Opts);
 
 static void*         DelayedDestroy(void*);
 
@@ -94,6 +94,8 @@ static void          DelayedDestroy(XrdPosixFile *fp);
 
        int           Fstat(struct stat &buf);
 
+       const char   *Location();
+
        void          HandleResponse(XrdCl::XRootDStatus *status,
                                     XrdCl::AnyObject    *response);
 
@@ -180,6 +182,7 @@ union {long long         currOffset;
       };
 
 char       *fPath;
+char       *fLoc;
 union {int  cOpt; int numTries;};
 char        isStream;
 };