git.m6w6.name Git - m6w6/libmemcached/blob - testing/lib/random.cpp

   1 #include "testing/lib/random.hpp"
   2 #include "testing/lib/Connection.hpp"
   3
   4 #include <chrono>
   5 #include <random>
   6
   7 #include <unistd.h> // getpid()
   8
   9
  10 template<typename T>
  11 enable_if_t<is_integral_v<T>, T> random_num(T min, T max) {
  12   using namespace chrono;
  13   using rnd = mt19937;
  14   using dst = uniform_int_distribution<T>;
  15
  16   auto time = duration_cast<nanoseconds>(system_clock::now().time_since_epoch());
  17   auto seed = static_cast<rnd::result_type>(time.count() % numeric_limits<T>::max());
  18   auto rgen = rnd{seed};
  19   return dst(min, max)(rgen);
  20 }
  21
  22 unsigned random_port() {
  23   retry:
  24   auto port = random_num(2<<9, 2<<15);
  25   Connection conn(port);
  26
  27   if (!conn.open()) {
  28     return port;
  29   }
  30   if (!conn.isOpen()) {
  31     return port;
  32   }
  33   goto retry;
  34 }
  35
  36 string random_port_string(const string &) {
  37   return to_string(random_port());
  38 }
  39
  40 string random_socket(const string &prefix) {
  41   return prefix + to_string(random_num(1U, UINT32_MAX)) + "@" + to_string(getpid()) + ".sock";
  42 }
  43
  44 string random_socket_or_port_string(const string &what) {
  45   if (what == "-s") {
  46     return random_socket();
  47   }
  48
  49   return to_string(random_port());
  50 }
  51
  52 string random_socket_or_port_flag(const string &binary) {
  53   (void) binary;
  54   return random_num(0, 1) ? "-p" : "-s";
  55 }
  56
  57 char random_ascii(char min, char max) {
  58   return static_cast<char>(random_num(min, max));
  59 }
  60
  61 string random_ascii_string(size_t len, char min, char max) {
  62   string s;
  63   s.reserve(len + 1);
  64
  65   for (size_t rem = 0; rem < len; ++rem) {
  66     s += random_ascii(min, max);
  67   }
  68
  69   s[len] = '\0';
  70   assert(strlen(s.c_str()) == s.size());
  71
  72   return s;
  73 }
  74
  75 pair<string, string> random_ascii_pair(size_t minlen, size_t maxlen) {
  76   return {
  77       random_ascii_string(random_num(minlen, maxlen)),
  78       random_ascii_string(random_num(minlen, maxlen))
  79   };
  80 }