mdw@git.distorted.org.uk Git - mLib/blob - sel/conn.c

   1 /* -*-c-*-
   2  *
   3  * Nonblocking connect handling
   4  *
   5  * (c) 1999 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the mLib utilities library.
  11  *
  12  * mLib is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * mLib is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with mLib; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Header files ------------------------------------------------------*/
  29
  30 #include <errno.h>
  31 #include <limits.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  36 #include <sys/types.h>
  37 #include <sys/socket.h>
  38
  39 #include <unistd.h>
  40 #include <fcntl.h>
  41
  42 #include "conn.h"
  43 #include "sel.h"
  44
  45 /*----- Main code ---------------------------------------------------------*/
  46
  47 /* --- @conn_connect@ --- *
  48  *
  49  * Arguments:   @int fd@ = file descriptor to try to connect
  50  *              @unsigned mode@ = what we can do to the file
  51  *              @void *p@ = pointer to connection context
  52  *
  53  * Returns:     ---
  54  *
  55  * Use:         Handles select results for pending connections.
  56  */
  57
  58 static void conn_connect(int fd, unsigned mode, void *p)
  59 {
  60 #ifndef PATH_MAX
  61 #  define PATH_MAX 1024
  62 #endif
  63
  64   conn *c = p;
  65   char buf[PATH_MAX + 8]; /* Big enough */
  66   socklen_t sinsz;
  67
  68   sinsz = sizeof(buf);
  69   sel_rmfile(&c->writer);
  70   if (getpeername(fd, (struct sockaddr *)buf, &sinsz) < 0) {
  71     int err;
  72     socklen_t errsz = sizeof(err);
  73     if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errsz) == 0)
  74       errno = err;
  75     close(fd);
  76     c->func(-1, c->p);
  77   } else
  78     c->func(fd, c->p);
  79 }
  80
  81 /* --- @conn_fd@ --- *
  82  *
  83  * Arguments:   @conn *c@ = pointer to connection block
  84  *              @sel_state *s@ = pointer to select state to attach to
  85  *              @int fd@ = file descriptor of socket
  86  *              @void (*func)(int fd, void *p) = handler function
  87  *              @void *p@ = argument for the handler function
  88  *
  89  * Returns:     ---
  90  *
  91  * Use:         Sets up a nonblocking connect job.  The socket should have a
  92  *              connect pending for it already.
  93  */
  94
  95 void conn_fd(conn *c, sel_state *s, int fd,
  96              void (*func)(int /*fd*/, void */*p*/),
  97              void *p)
  98 {
  99   c->func = func;
 100   c->p = p;
 101   sel_initfile(s, &c->writer, fd, SEL_WRITE, conn_connect, c);
 102   sel_addfile(&c->writer);
 103 }
 104
 105 /* --- @conn_init@ --- *
 106  *
 107  * Arguments:   @conn *c@ = pointer to connection block
 108  *              @sel_state *s@ = pointer to select state to attach to
 109  *              @int fd@ = file descriptor of socket to connect
 110  *              @struct sockaddr *dst@ = destination address
 111  *              @int dsz@ = size of destination address
 112  *              @void (*func)(int fd, void *p) = handler function
 113  *              @void *p@ = argument for the handler function
 114  *
 115  * Returns:     Zero on success, nonzero on failure.
 116  *
 117  * Use:         Sets up a nonblocking connect job.  The socket should already
 118  *              be bound if you care about that sort of thing.  When the
 119  *              connection completes, the handler function is called with the
 120  *              connected socket as an argument.  If the connect fails rather
 121  *              than completes, the socket is closed, and the handler is
 122  *              informed of this by being passed a negative file descriptor.
 123  *              In either case, the select job is then removed.
 124  */
 125
 126 int conn_init(conn *c, sel_state *s, int fd,
 127               struct sockaddr *dst, int dsz,
 128               void (*func)(int /*fd*/, void */*p*/),
 129               void *p)
 130 {
 131   int f;
 132
 133   if ((f = fcntl(fd, F_GETFL)) < 0 || fcntl(fd, F_SETFL, f | O_NONBLOCK))
 134     goto fail;
 135
 136   if (!connect(fd, dst, dsz))
 137     func(fd, p);
 138   else if (errno != EINPROGRESS)
 139     goto fail;
 140   else
 141     conn_fd(c, s, fd, func, p);
 142   return (0);
 143
 144 fail:
 145   close(fd);
 146   return (-1);
 147 }
 148
 149 /* --- @conn_kill@ --- *
 150  *
 151  * Arguments:   @conn *c@ = pointer to connection to dispose of
 152  *
 153  * Returns:     ---
 154  *
 155  * Use:         Disposes of a connection when it's not wanted any more.
 156  */
 157
 158 void conn_kill(conn *c)
 159 {
 160   if (c->writer.fd != -1) {
 161     close(c->writer.fd);
 162     sel_rmfile(&c->writer);
 163     c->writer.fd = -1;
 164   }
 165 }
 166
 167 /*----- That's all, folks -------------------------------------------------*/