Clarify the BIO_seek() mess and related issues.

[oweals/openssl.git] / doc / crypto / BIO_s_connect.pod

diff --git a/doc/crypto/BIO_s_connect.pod b/doc/crypto/BIO_s_connect.pod
index 08a9e6473e780f6add65a8f0110f2340db2bfe48..fe1aa679d441b7b4e81f8a04854fe94fd92b6b1d 100644 (file)
--- a/doc/crypto/BIO_s_connect.pod
+++ b/doc/crypto/BIO_s_connect.pod
@@ -2,7 +2,10 @@
 
 =head1 NAME
 
 
 =head1 NAME
 

-       BIO_s_connect - connect BIO
+BIO_s_connect, BIO_set_conn_hostname, BIO_set_conn_port,
+BIO_set_conn_ip, BIO_set_conn_int_port, BIO_get_conn_hostname,
+BIO_get_conn_port, BIO_get_conn_ip, BIO_get_conn_int_port,
+BIO_set_nbio, BIO_do_connect - connect BIO

 
 =head1 SYNOPSIS
 
 
 =head1 SYNOPSIS
 


@@ -63,24 +66,26 @@ fails a standard table of port names will be used. Currently the
 list is http, telnet, socks, https, ssl, ftp, gopher and wais.
 
 BIO_set_conn_ip() sets the IP address to B<ip> using binary form,
 list is http, telnet, socks, https, ssl, ftp, gopher and wais.
 
 BIO_set_conn_ip() sets the IP address to B<ip> using binary form,

-that is four bytes specifying the IP address in big endian form.
+that is four bytes specifying the IP address in big-endian form.

 
 BIO_set_conn_int_port() sets the port using B<port>. B<port> should
 be of type (int *).
 
 BIO_get_conn_hostname() returns the hostname of the connect BIO or
 
 BIO_set_conn_int_port() sets the port using B<port>. B<port> should
 be of type (int *).
 
 BIO_get_conn_hostname() returns the hostname of the connect BIO or

-NULL if the BIO is initialised but no hostname is set.
+NULL if the BIO is initialized but no hostname is set.

 This return value is an internal pointer which should not be modified.
 
 BIO_get_conn_port() returns the port as a string.
 
 BIO_get_conn_ip() returns the IP address in binary form.
 
 This return value is an internal pointer which should not be modified.
 
 BIO_get_conn_port() returns the port as a string.
 
 BIO_get_conn_ip() returns the IP address in binary form.
 

-BIO_get_conn_int_port() returns the host name as an int.
+BIO_get_conn_int_port() returns the port as an int.

 
 BIO_set_nbio() sets the non blocking I/O flag to B<n>. If B<n> is
 zero then blocking I/O is set. If B<n> is 1 then non blocking I/O
 
 BIO_set_nbio() sets the non blocking I/O flag to B<n>. If B<n> is
 zero then blocking I/O is set. If B<n> is 1 then non blocking I/O

-is set.
+is set. Blocking I/O is the default. The call to BIO_set_nbio()
+should be made before the connection is established because 
+non blocking I/O is set during the connect process.

 
 BIO_do_connect() attempts to connect the supplied BIO. It returns 1
 if the connection was established successfully. A zero or negative
 
 BIO_do_connect() attempts to connect the supplied BIO. It returns 1
 if the connection was established successfully. A zero or negative


@@ -88,7 +93,6 @@ value is returned if the connection could not be established, the
 call BIO_should_retry() should be used for non blocking connect BIOs
 to determine if the call should be retried.
 
 call BIO_should_retry() should be used for non blocking connect BIOs
 to determine if the call should be retried.
 

-

 =head1 NOTES
 
 If blocking I/O is set then a non positive return value from any
 =head1 NOTES
 
 If blocking I/O is set then a non positive return value from any


@@ -96,15 +100,19 @@ I/O call is caused by an error condition, although a zero return
 will normally mean that the connection was closed.
 
 If the port name is supplied as part of the host name then this will
 will normally mean that the connection was closed.
 
 If the port name is supplied as part of the host name then this will

-override any value set with BIO_set_conn_port().
+override any value set with BIO_set_conn_port(). This may be undesirable
+if the application does not wish to allow connection to arbitrary
+ports. This can be avoided by checking for the presence of the ':'
+character in the passed hostname and either indicating an error or
+truncating the string at that point.

 
 The values returned by BIO_get_conn_hostname(), BIO_get_conn_port(),
 BIO_get_conn_ip() and BIO_get_conn_int_port() are updated when a
 connection attempt is made. Before any connection attempt the values
 returned are those set by the application itself.
 
 
 The values returned by BIO_get_conn_hostname(), BIO_get_conn_port(),
 BIO_get_conn_ip() and BIO_get_conn_int_port() are updated when a
 connection attempt is made. Before any connection attempt the values
 returned are those set by the application itself.
 

-Applications do not have to call BIO_do_connect() but can do so to
-separate the connection process from other I/O processing.
+Applications do not have to call BIO_do_connect() but may wish to do
+so to separate the connection process from other I/O processing.

 
 If non blocking I/O is set then retries will be requested as appropriate.
 
 
 If non blocking I/O is set then retries will be requested as appropriate.
 


@@ -112,7 +120,7 @@ It addition to BIO_should_read() and BIO_should_write() it is also
 possible for BIO_should_io_special() to be true during the initial
 connection process with the reason BIO_RR_CONNECT. If this is returned
 then this is an indication that a connection attempt would block,
 possible for BIO_should_io_special() to be true during the initial
 connection process with the reason BIO_RR_CONNECT. If this is returned
 then this is an indication that a connection attempt would block,

-the application should then take appropiate action to wait until
+the application should then take appropriate action to wait until

 the underlying socket has connected and retry the call.
 
 =head1 RETURN VALUES
 the underlying socket has connected and retry the call.
 
 =head1 RETURN VALUES


@@ -120,11 +128,54 @@ the underlying socket has connected and retry the call.
 BIO_s_connect() returns the connect BIO method.
 
 BIO_get_fd() returns the socket or -1 if the BIO has not
 BIO_s_connect() returns the connect BIO method.
 
 BIO_get_fd() returns the socket or -1 if the BIO has not

-been initialised.
+been initialized.

 
 

-=head1 EXAMPLES
+BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_set_conn_ip() and
+BIO_set_conn_int_port() always return 1.
+
+BIO_get_conn_hostname() returns the connected hostname or NULL is
+none was set.
+
+BIO_get_conn_port() returns a string representing the connected
+port or NULL if not set.
+
+BIO_get_conn_ip() returns a pointer to the connected IP address in
+binary form or all zeros if not set.
+
+BIO_get_conn_int_port() returns the connected port or 0 if none was
+set.
+
+BIO_set_nbio() always returns 1.
+
+BIO_do_connect() returns 1 if the connection was successfully
+established and 0 or -1 if the connection failed.
+
+=head1 EXAMPLE
+
+This is example connects to a webserver on the local host and attempts
+to retrieve a page and copy the result to standard output.
+
+
+ BIO *cbio, *out;
+ int len;
+ char tmpbuf[1024];
+ ERR_load_crypto_strings();
+ cbio = BIO_new_connect("localhost:http");
+ out = BIO_new_fp(stdout, BIO_NOCLOSE);
+ if(BIO_do_connect(cbio) <= 0) {
+       fprintf(stderr, "Error connecting to server\n");
+       ERR_print_errors_fp(stderr);
+       /* whatever ... */
+       }
+ BIO_puts(cbio, "GET / HTTP/1.0\n\n");
+ for(;;) {     
+       len = BIO_read(cbio, tmpbuf, 1024);
+       if(len <= 0) break;
+       BIO_write(out, tmpbuf, len);
+ }
+ BIO_free(cbio);
+ BIO_free(out);

 
 

-TBA

 
 =head1 SEE ALSO
 
 
 =head1 SEE ALSO