XrdNetCache Class Reference

#include <XrdNetCache.hh>

Collaboration diagram for XrdNetCache:

Classes
union	anItem.__unnamed109__

Public Member Functions
	XrdNetCache (int psize=987, int csize=1597)
	~XrdNetCache ()
void	Add (XrdNetAddrInfo *hAddr, const char *hName)
char *	Find (XrdNetAddrInfo *hAddr)

Static Public Member Functions
static void	SetKT (int ktval)

Detailed Description

Definition at line 41 of file XrdNetCache.hh.

---

Class Documentation

XrdNetCache::anItem.__unnamed109__

union XrdNetCache::anItem.__unnamed109__

Definition at line 96 of file XrdNetCache.hh.

Collaboration diagram for XrdNetCache::anItem.__unnamed109__:

Class Members
int	aV4[4]
long long	aV6[2]
char	aVal[16]

Constructor & Destructor Documentation

XrdNetCache()

XrdNetCache::XrdNetCache	(	int	psize = 987,
		int	csize = 1597
	)

Constructor. When allocateing a new hash, two adjacent Fibonocci numbers. The series is simply n[j] = n[j-1] + n[j-2].

Parameters

psize	the correct Fibonocci antecedent to csize.
csize	the initial size of the table.

Definition at line 49 of file XrdNetCache.cc.

{
     prevtablesize = psize;
     nashtablesize = csize;
     Threshold     = (csize * LoadMax) / 100;
     nashnum       = 0;
     nashtable     = (anItem **)malloc( (size_t)(csize*sizeof(anItem *)) );
     memset((void *)nashtable, 0, (size_t)(csize*sizeof(anItem *)));
}

~XrdNetCache()

XrdNetCache::~XrdNetCache ( )

inline

Destructor. The XrdNetCache object is not designed to be deleted. Doing so will cause memory to be lost.

Definition at line 89 of file XrdNetCache.hh.

{} // Never gets deleted

Member Function Documentation

Add()

void XrdNetCache::Add	(	XrdNetAddrInfo *	hAddr,
		const char *	hName
	)

Add an address-hostname association to the cache. The address must be an INET family address; otherwise it is not added.

Parameters

hAddr	points to the address of the name.
hName	points to the name to be associated with the address.

Definition at line 63 of file XrdNetCache.cc.

{
   anItem Item, *hip;
   int    kent;
 
// Get the key and make sure this is a valid address (should be)
//
   if (!GenKey(Item, hAddr)) return;
 
// We may be in a race condition, check we have this item
//
   myMutex.Lock();
   if ((hip = Locate(Item)))
      {if (hip->hName) free(hip->hName);
       hip->hName = strdup(hName);
       hip->expTime = time(0) + keepTime;
       myMutex.UnLock();
       return;
      }
 
// Check if we should expand the table
//
   if (++nashnum > Threshold) Expand();
 
// Allocate a new entry
//
   hip = new anItem(Item, hName, keepTime);
 
// Add the entry to the table
//
   kent = hip->aHash % nashtablesize;
   hip->Next = nashtable[kent];
   nashtable[kent] = hip;
   myMutex.UnLock();
}

References XrdSysMutex::Lock(), and XrdSysMutex::UnLock().

Referenced by XrdNetAddrInfo::Resolve().

Here is the call graph for this function:

Here is the caller graph for this function:

Find()

char * XrdNetCache::Find

(

XrdNetAddrInfo *

hAddr

)

Locate an address-hostname association in the cache.

Parameters

hAddr

points to the address of the name.

Returns

Success: an strdup'd string of the corresponding name. Failure: 0;

Definition at line 148 of file XrdNetCache.cc.

{
  anItem Item, *nip, *pip = 0;
  int kent;
 
// Get the hash for this address
//
   if (!GenKey(Item, hAddr)) return 0;
 
// Compute position of the hash table entry
//
   myMutex.Lock();
   kent = Item.aHash%nashtablesize;
 
// Find the entry
//
   nip = nashtable[kent];
   while(nip && *nip != Item) {pip = nip; nip = nip->Next;}
   if (!nip) {myMutex.UnLock(); return 0;}
 
// Make sure entry has not expired
//
   if (nip->expTime > time(0))
      {char *hName = strdup(nip->hName);
       myMutex.UnLock();
       return hName;
      }
 
// Remove the entry and return not found
//
   if (pip) pip->Next       = nip->Next;
      else  nashtable[kent] = nip->Next;
   myMutex.UnLock();
   delete nip;
   return 0;
}

References XrdSysMutex::Lock(), and XrdSysMutex::UnLock().

Referenced by XrdNetAddrInfo::Format(), and XrdNetAddrInfo::Name().

Here is the call graph for this function:

Here is the caller graph for this function:

SetKT()

static void XrdNetCache::SetKT ( int  ktval )

inlinestatic

Set the default keep time for entries in the cache during initialization.

Parameters

ktval

the number of seconds to keep an entry in the cache.

Definition at line 72 of file XrdNetCache.hh.

{keepTime = ktval;}

---

The documentation for this class was generated from the following files:

• XrdNetCache.hh
• XrdNetCache.cc