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#include <unistd.h>
#include <errno.h>
#include <stdlib.h>

static int fdconsumed = 0;

override(`bind', `
  {
    int dupfd;
    int port;
    int argport;
    char *dupfd_str;
    char *port_str;

    dupfd_str = getenv("BINDFD");
    port_str = getenv("BINDPORT");

    if (dupfd_str == NULL) {
      fprintf(stderr, "BINDFD not set in environment\n");
      return -1;
    }

    if (port_str == NULL) {
      fprintf(stderr, "BINDPORT not set in environment\n");
      return -1;
    }

    dupfd = atoi(dupfd_str); 
    port = htons(atoi(port_str));
    argport = ((struct sockaddr_in *)addr)->sin_port;
    if (port == argport) {
      dup2(dupfd, s);
      close(dupfd);
      fdconsumed = 1;
      return 0;
    } else {
      return real_func(s, addr, addrlen);
    }

    return 0;
  }
')