src/port/noblock.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * noblock.c
   4  *        set a file descriptor as blocking or non-blocking
   5  *
   6  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * IDENTIFICATION
  10  *        src/port/noblock.c
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14
  15 #include "c.h"
  16
  17 #include <fcntl.h>
  18
  19
  20 /*
  21  * Put socket into nonblock mode.
  22  * Returns true on success, false on failure.
  23  */
  24 bool
  25 pg_set_noblock(pgsocket sock)
  26 {
  27 #if !defined(WIN32)
  28         int                     flags;
  29
  30         flags = fcntl(sock, F_GETFL);
  31         if (flags < 0)
  32                 return false;
  33         if (fcntl(sock, F_SETFL, (flags | O_NONBLOCK)) == -1)
  34                 return false;
  35         return true;
  36 #else
  37         unsigned long ioctlsocket_ret = 1;
  38
  39         /* Returns non-0 on failure, while fcntl() returns -1 on failure */
  40         return (ioctlsocket(sock, FIONBIO, &ioctlsocket_ret) == 0);
  41 #endif
  42 }
  43
  44 /*
  45  * Put socket into blocking mode.
  46  * Returns true on success, false on failure.
  47  */
  48 bool
  49 pg_set_block(pgsocket sock)
  50 {
  51 #if !defined(WIN32)
  52         int                     flags;
  53
  54         flags = fcntl(sock, F_GETFL);
  55         if (flags < 0)
  56                 return false;
  57         if (fcntl(sock, F_SETFL, (flags & ~O_NONBLOCK)) == -1)
  58                 return false;
  59         return true;
  60 #else
  61         unsigned long ioctlsocket_ret = 0;
  62
  63         /* Returns non-0 on failure, while fcntl() returns -1 on failure */
  64         return (ioctlsocket(sock, FIONBIO, &ioctlsocket_ret) == 0);
  65 #endif
  66 }