external/ibm-public/postfix/dist/src/util/stream_connect.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      stream_connect 3
   6 /* SUMMARY
   7 /*      connect to stream listener
   8 /* SYNOPSIS
   9 /*      #include <connect.h>
  10 /*
  11 /*      int     stream_connect(path, block_mode, timeout)
  12 /*      const char *path;
  13 /*      int     block_mode;
  14 /*      int     timeout;
  15 /* DESCRIPTION
  16 /*      stream_connect() connects to a stream listener for the specified
  17 /*      pathname, and returns the resulting file descriptor.
  18 /*
  19 /*      Arguments:
  20 /* .IP path
  21 /*      Null-terminated string with listener endpoint name.
  22 /* .IP block_mode
  23 /*      Either NON_BLOCKING for a non-blocking stream, or BLOCKING for
  24 /*      blocking mode. However, a stream connection succeeds or fails
  25 /*      immediately.
  26 /* .IP timeout
  27 /*      This argument is ignored; it is present for compatibility with
  28 /*      other interfaces. Stream connections succeed or fail immediately.
  29 /* DIAGNOSTICS
  30 /*      The result is -1 in case the connection could not be made.
  31 /*      Fatal errors: other system call failures.
  32 /* LICENSE
  33 /* .ad
  34 /* .fi
  35 /*      The Secure Mailer license must be distributed with this software.
  36 /* AUTHOR(S)
  37 /*      Wietse Venema
  38 /*      IBM T.J. Watson Research
  39 /*      P.O. Box 704
  40 /*      Yorktown Heights, NY 10598, USA
  41 /*--*/
  42
  43 /* System library. */
  44
  45 #include <sys_defs.h>
  46
  47 #ifdef STREAM_CONNECTIONS
  48
  49 #include <sys/stat.h>
  50 #include <unistd.h>
  51 #include <fcntl.h>
  52 #include <errno.h>
  53 #include <stropts.h>
  54
  55 #endif
  56
  57 /* Utility library. */
  58
  59 #include <msg.h>
  60 #include <connect.h>
  61
  62 /* stream_connect - connect to stream listener */
  63
  64 int     stream_connect(const char *path, int block_mode, int unused_timeout)
  65 {
  66 #ifdef STREAM_CONNECTIONS
  67     const char *myname = "stream_connect";
  68     int     pair[2];
  69     int     fifo;
  70
  71     /*
  72      * The requested file system object must exist, otherwise we can't reach
  73      * the server.
  74      */
  75     if ((fifo = open(path, O_WRONLY | O_NONBLOCK, 0)) < 0)
  76         return (-1);
  77
  78     /*
  79      * This is for {unix,inet}_connect() compatibility.
  80      */
  81     if (block_mode == BLOCKING)
  82         non_blocking(fifo, BLOCKING);
  83
  84     /*
  85      * Create a pipe, and send one pipe end to the server.
  86      */
  87     if (pipe(pair) < 0)
  88         msg_fatal("%s: pipe: %m", myname);
  89     if (ioctl(fifo, I_SENDFD, pair[1]) < 0)
  90         msg_fatal("%s: send file descriptor: %m", myname);
  91     close(pair[1]);
  92
  93     /*
  94      * This is for {unix,inet}_connect() compatibility.
  95      */
  96     if (block_mode == NON_BLOCKING)
  97         non_blocking(pair[0], NON_BLOCKING);
  98
  99     /*
 100      * Cleanup.
 101      */
 102     close(fifo);
 103
 104     /*
 105      * Keep the other end of the pipe.
 106      */
 107     return (pair[0]);
 108 #else
 109     msg_fatal("stream connections are not implemented");
 110 #endif
 111 }