pdns/dumresp.cc

   1 #ifdef HAVE_CONFIG_H
   2 #include "config.h"
   3 #endif
   4 #include "iputils.hh"
   5 #include "sstuff.hh"
   6 #include "statbag.hh"
   7 #include <atomic>
   8 #include <sys/mman.h>
   9 #include <thread>
  10 StatBag S;
  11
  12 std::atomic<uint64_t>* g_counter;
  13
  14 void printStatus()
  15 {
  16   auto prev= g_counter->load();
  17   for(;;) {
  18     sleep(1);
  19     cout<<g_counter->load()-prev<<"\t"<<g_counter->load()<<endl;
  20     prev=g_counter->load();
  21   }
  22 }
  23
  24 void usage() {
  25   cerr<<"Syntax: dumresp LOCAL-ADDRESS LOCAL-PORT NUMBER-OF-PROCESSES"<<endl;
  26 }
  27
  28 int main(int argc, char** argv)
  29 try
  30 {
  31   for(int i = 1; i < argc; i++) {
  32     if((string) argv[i] == "--help"){
  33       usage();
  34       return(EXIT_SUCCESS);
  35     }
  36
  37     if((string) argv[i] == "--version"){
  38       cerr<<"dumresp "<<VERSION<<endl;
  39       return(EXIT_SUCCESS);
  40     }
  41   }
  42
  43   if(argc != 4) {
  44     usage();
  45     exit(EXIT_FAILURE);
  46   }
  47
  48   auto ptr = mmap(NULL, sizeof(std::atomic<uint64_t>), PROT_READ | PROT_WRITE,
  49                   MAP_SHARED | MAP_ANONYMOUS, -1, 0);
  50
  51   g_counter = new(ptr) std::atomic<uint64_t>();
  52
  53   int i=1;
  54   for(; i < atoi(argv[3]); ++i) {
  55     if(!fork())
  56       break;
  57   }
  58   if(i==1) {
  59     std::thread t(printStatus);
  60     t.detach();
  61   }
  62
  63   ComboAddress local(argv[1], atoi(argv[2]));
  64   Socket s(local.sin4.sin_family, SOCK_DGRAM);
  65 #ifdef SO_REUSEPORT
  66   int one=1;
  67   if(setsockopt(s.getHandle(), SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)) < 0)
  68     unixDie("setsockopt for REUSEPORT");
  69 #endif
  70
  71   s.bind(local);
  72   cout<<"Bound to "<<local.toStringWithPort()<<endl;
  73   char buffer[1500];
  74   struct dnsheader* dh = (struct dnsheader*)buffer;
  75   int len;
  76   ComboAddress rem=local;
  77   socklen_t socklen = rem.getSocklen();
  78   for(;;) {
  79     len=recvfrom(s.getHandle(), buffer, sizeof(buffer), 0, (struct sockaddr*)&rem, &socklen);
  80     (*g_counter)++;
  81     if(len < 0)
  82       unixDie("recvfrom");
  83
  84     if(dh->qr)
  85       continue;
  86     dh->qr=1;
  87     dh->ad=0;
  88     if(sendto(s.getHandle(), buffer, len, 0,  (struct sockaddr*)&rem, socklen) < 0)
  89       unixDie("sendto");
  90
  91   }
  92 }
  93 catch(std::exception& e)
  94 {
  95   cerr<<"Fatal error: "<<e.what()<<endl;
  96   exit(EXIT_FAILURE);
  97 }