pdns/statbag.hh

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #ifndef STATBAG_HH
  23 #define STATBAG_HH
  24 #include <pthread.h>
  25 #include <map>
  26 #include <functional>
  27 #include <string>
  28 #include <vector>
  29 #include "lock.hh"
  30 #include "namespaces.hh"
  31 #include "iputils.hh"
  32 #include <boost/circular_buffer.hpp>
  33
  34
  35
  36 template<typename T, typename Comp=std::less<T> >
  37 class StatRing
  38 {
  39 public:
  40   StatRing(unsigned int size=10000);
  41   void account(const T &item);
  42
  43   unsigned int getSize();
  44   void resize(unsigned int newsize);
  45   void reset();
  46   void setHelp(const string &str);
  47   string getHelp();
  48
  49   vector<pair<T, unsigned int> > get() const;
  50 private:
  51   static bool popisort(const pair<T,int> &a, const pair<T,int> &b)
  52   {
  53     return (a.second > b.second);
  54   }
  55
  56   boost::circular_buffer<T> d_items;
  57   mutable pthread_mutex_t d_lock;
  58   string d_help;
  59 };
  60
  61
  62 //! use this to gather and query statistics
  63 class StatBag
  64 {
  65   map<string, AtomicCounter *> d_stats;
  66   map<string, string> d_keyDescrips;
  67   map<string,StatRing<string> >d_rings;
  68   map<string,StatRing<SComboAddress> >d_comborings;
  69   typedef boost::function<uint64_t(const std::string&)> func_t;
  70   typedef map<string, func_t> funcstats_t;
  71   funcstats_t d_funcstats;
  72   bool d_doRings;
  73
  74 public:
  75   StatBag(); //!< Naked constructor. You need to declare keys before this class becomes useful
  76   ~StatBag();
  77   void declare(const string &key, const string &descrip=""); //!< Before you can store or access a key, you need to declare it
  78   void declare(const string &key, const string &descrip, func_t func); //!< Before you can store or access a key, you need to declare it
  79
  80   void declareRing(const string &name, const string &title, unsigned int size=10000);
  81   void declareComboRing(const string &name, const string &help, unsigned int size=10000);
  82   vector<pair<string, unsigned int> >getRing(const string &name);
  83   string getRingTitle(const string &name);
  84   void ringAccount(const char* name, const string &item)
  85   {
  86     if(d_doRings)  {
  87       if(!d_rings.count(name))
  88         throw runtime_error("Attempting to account to non-existent ring '"+std::string(name)+"'");
  89
  90       d_rings[name].account(item);
  91     }
  92   }
  93   void ringAccount(const char* name, const ComboAddress &item)
  94   {
  95     if(d_doRings) {
  96       if(!d_comborings.count(name))
  97         throw runtime_error("Attempting to account to non-existent comboring '"+std::string(name)+"'");
  98       d_comborings[name].account(item);
  99     }
 100   }
 101
 102   void doRings()
 103   {
 104     d_doRings=true;
 105   }
 106
 107   vector<string>listRings();
 108   bool ringExists(const string &name);
 109   void resetRing(const string &name);
 110   void resizeRing(const string &name, unsigned int newsize);
 111   unsigned int getRingSize(const string &name);
 112
 113   string directory(); //!< Returns a list of all data stored
 114   vector<string> getEntries(); //!< returns a vector with datums (items)
 115   string getDescrip(const string &item); //!< Returns the description of this datum/item
 116   void exists(const string &key); //!< call this function to throw an exception in case a key does not exist
 117   inline void deposit(const string &key, int value); //!< increment the statistics behind this key by value amount
 118   inline void inc(const string &key); //!< increase this key's value by one
 119   void set(const string &key, unsigned long value); //!< set this key's value
 120   unsigned long read(const string &key); //!< read the value behind this key
 121   unsigned long readZero(const string &key); //!< read the value behind this key, and zero it afterwards
 122   AtomicCounter *getPointer(const string &key); //!< get a direct pointer to the value behind a key. Use this for high performance increments
 123   string getValueStr(const string &key); //!< read a value behind a key, and return it as a string
 124   string getValueStrZero(const string &key); //!< read a value behind a key, and return it as a string, and zero afterwards
 125 };
 126
 127 inline void StatBag::deposit(const string &key, int value)
 128 {
 129   exists(key);
 130
 131   *d_stats[key]+=value;
 132 }
 133
 134 inline void StatBag::inc(const string &key)
 135 {
 136   deposit(key,1);
 137 }
 138
 139
 140 #endif /* STATBAG_HH */