ext/kgio/missing_accept4.h

   1 #ifndef HAVE_ACCEPT4
   2 #  ifndef _GNU_SOURCE
   3 #    define _GNU_SOURCE
   4 #  endif
   5 #  include <sys/types.h>
   6 #  include <sys/socket.h>
   7 #  ifndef SOCK_CLOEXEC
   8 #    if (FD_CLOEXEC == O_NONBLOCK)
   9 #      define SOCK_CLOEXEC 1
  10 #      define SOCK_NONBLOCK 2
  11 #    else
  12 #      define SOCK_CLOEXEC FD_CLOEXEC
  13 #      define SOCK_NONBLOCK O_NONBLOCK
  14 #    endif
  15 #  endif
  16 #endif /* !HAVE_ACCEPT4 */
  17
  18 /* accept4() is currently a Linux-only goodie */
  19 static int
  20 my_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags)
  21 {
  22         int fd = accept(sockfd, addr, addrlen);
  23
  24         if (fd >= 0) {
  25                 if ((flags & SOCK_CLOEXEC) == SOCK_CLOEXEC)
  26                         (void)fcntl(fd, F_SETFD, FD_CLOEXEC);
  27
  28                 /*
  29                  * Some systems inherit O_NONBLOCK across accept().
  30                  * We also expect our users to use MSG_DONTWAIT under
  31                  * Linux, so fcntl() is completely unnecessary
  32                  * in most cases...
  33                  */
  34                 if ((flags & SOCK_NONBLOCK) == SOCK_NONBLOCK) {
  35                         int fl = fcntl(fd, F_GETFL);
  36
  37                         /*
  38                          * unconditional, OSX 10.4 (and maybe other *BSDs)
  39                          * F_GETFL returns a false O_NONBLOCK with TCP sockets
  40                          * (but not UNIX sockets) [ruby-talk:274079]
  41                          */
  42                         (void)fcntl(fd, F_SETFL, fl | O_NONBLOCK);
  43                 }
  44
  45                 /*
  46                  * nothing we can do about fcntl() errors in this wrapper
  47                  * function, let the user (Ruby) code figure it out
  48                  */
  49                 errno = 0;
  50         }
  51         return fd;
  52 }
  53
  54 typedef int accept_fn_t(int, struct sockaddr *, socklen_t *, int);
  55 #ifdef HAVE_ACCEPT4
  56 static accept_fn_t *accept_fn = accept4;
  57 #else
  58 static accept_fn_t *accept_fn = my_accept4;
  59 #endif