mdw@git.distorted.org.uk Git - fwd/blob - blast.c

   1 #include <assert.h>
   2 #include <ctype.h>
   3 #include <errno.h>
   4 #include <math.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8
   9 #include <sys/types.h>
  10 #include <sys/time.h>
  11 #include <unistd.h>
  12 #include <sys/socket.h>
  13 #include <netinet/in.h>
  14 #include <arpa/inet.h>
  15 #include <netdb.h>
  16
  17 #include <mLib/alloc.h>
  18 #include <mLib/conn.h>
  19 #include <mLib/macros.h>
  20 #include <mLib/mdwopt.h>
  21 #include <mLib/quis.h>
  22 #include <mLib/report.h>
  23 #include <mLib/sel.h>
  24 #include <mLib/tv.h>
  25
  26 typedef struct blast {
  27   conn c;
  28   sel_timer t;
  29 } blast;
  30
  31 #define sin saddrin
  32 static struct sockaddr_in sin;
  33 static sel_state sel;
  34 static struct timeval ctv = { 0, 500000 };
  35 static sel_timer sec;
  36 static unsigned count = 0;
  37
  38 static void IGNORABLE timers(void);
  39
  40 static void stats(struct timeval *tv, void *p)
  41 {
  42   static char baton[5] = "/-\\|";
  43   static char *bt = baton;
  44   struct timeval ttv;
  45   printf("\r%c %u connections/second", *bt++, count);
  46   if (!*bt)
  47     bt = baton;
  48   fflush(stdout);
  49   count = 0;
  50   TV_ADDL(&ttv, tv, 1, 0);
  51   sel_addtimer(&sel, &sec, &ttv, stats, p);
  52 }
  53
  54 static void newconn(blast *b);
  55
  56 static void retry(struct timeval *tv, void *p)
  57 {
  58   blast *b = p;
  59   newconn(b);
  60 }
  61
  62 static void backoff(blast *b)
  63 {
  64   struct timeval tv;
  65   unsigned r = rand();
  66   double q = RAND_MAX / 5;
  67   gettimeofday(&tv, 0);
  68   TV_ADDL(&tv, &tv, r / q, (r % (unsigned)q) * (MILLION / q));
  69   sel_addtimer(&sel, &b->t, &tv, retry, b);
  70 }
  71
  72 static void connected(int fd, void *p)
  73 {
  74   blast *b = p;
  75   sel_rmtimer(&b->t);
  76   if (fd == -1)
  77     backoff(b);
  78   else {
  79     count++;
  80     close(fd);
  81   }
  82   newconn(b);
  83 }
  84
  85 static void timeout(struct timeval *tv, void *p)
  86 {
  87   blast *b = p;
  88   conn_kill(&b->c);
  89   newconn(b);
  90 }
  91
  92 static void timers(void)
  93 {
  94   struct tab { void (*func)(struct timeval *tv, void *p); const char *name; }
  95   tab[] = { { retry, "retry" }, {timeout, "timeout"}, { stats, "stats" }, { 0,
  96   0 }};
  97   sel_timer *t = sel.timers;
  98   while (t) {
  99     struct tab *q; for (q = tab; q->func != t->func; q++) ;
 100 /*     assert(t->prev->next == t); */
 101     printf("%lu.%06lu  %p  %s\n", t->tv.tv_sec, t->tv.tv_usec, t->p, q->name);
 102     assert(t != t->next);
 103     t = t->next;
 104   }
 105   puts("");
 106 }
 107
 108 static void newconn(blast *b)
 109 {
 110   int fd = socket(PF_INET, SOCK_STREAM, 0);
 111   struct timeval tv;
 112   if (fd < 0)
 113     goto fail;
 114   gettimeofday(&tv, 0);
 115   TV_ADD(&tv, &tv, &ctv);
 116   sel_addtimer(&sel, &b->t, &tv, timeout, b);
 117   if (conn_init(&b->c, &sel, fd, (struct sockaddr *)&sin, sizeof(sin),
 118                 connected, b))
 119     goto fail;
 120   return;
 121
 122 fail:
 123   sel_rmtimer(&b->t);
 124   backoff(b);
 125 }
 126
 127 int main(int argc, char *argv[])
 128 {
 129   blast *b;
 130   size_t n = 256;
 131
 132   ego(argv[0]);
 133
 134   for (;;) {
 135     int i = getopt(argc, argv, "t:n:");
 136     if (i < 0)
 137       break;
 138     switch (i) {
 139       case 't': {
 140         double t = strtod(optarg, 0);
 141         double s = modf(t, &t);
 142         ctv.tv_sec = t;
 143         ctv.tv_usec = s * MILLION;
 144       } break;
 145       case 'n':
 146         n = atoi(optarg);
 147         break;
 148       default:
 149         exit(1);
 150     }
 151   }
 152
 153   argv += optind;
 154   argc -= optind;
 155   if (argc != 2) {
 156     pquis(stderr, "Usage: $ [-t TIME] [-n COUNT] HOST PORT\n");
 157     exit(1);
 158   }
 159
 160   sel_init(&sel);
 161   sin.sin_family = AF_INET;
 162
 163   {
 164     struct hostent *h = gethostbyname(argv[0]);
 165     if (!h)
 166       die(1, "bad hostname `%s'", argv[0]);
 167     memcpy(&sin.sin_addr, h->h_addr, sizeof(struct in_addr));
 168   }
 169
 170   if (isdigit((unsigned char)argv[1][0]))
 171     sin.sin_port = htons(atoi(argv[1]));
 172   else {
 173     struct servent *s = getservbyname(argv[1], "tcp");
 174     if (!s)
 175       die(1, "bad service name `%s'", argv[1]);
 176     sin.sin_port = s->s_port;
 177   }
 178
 179   b = xmalloc(n * sizeof(blast));
 180
 181   {
 182     int i;
 183     for (i = 0; i < n; i++)
 184       newconn(&b[i]);
 185   }
 186
 187   {
 188     struct timeval tv;
 189     gettimeofday(&tv, 0);
 190     tv.tv_sec++;
 191     sel_addtimer(&sel, &sec, &tv, stats, 0);
 192   }
 193
 194   for (;;) {
 195     sel_select(&sel);
 196   }
 197 }