Return to libpdel.3 CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / libpdel

libpdel

.\" Copyright (c) 2001-2002 Packet Design, LLC.
.\" All rights reserved.
.\" 
.\" Subject to the following obligations and disclaimer of warranty,
.\" use and redistribution of this software, in source or object code
.\" forms, with or without modifications are expressly permitted by
.\" Packet Design; provided, however, that:
.\" 
.\"    (i)  Any and all reproductions of the source or object code
.\"         must include the copyright notice above and the following
.\"         disclaimer of warranties; and
.\"    (ii) No rights are granted, in any manner or form, to use
.\"         Packet Design trademarks, including the mark "PACKET DESIGN"
.\"         on advertising, endorsements, or otherwise except as such
.\"         appears in the above copyright notice or in the software.
.\" 
.\" THIS SOFTWARE IS BEING PROVIDED BY PACKET DESIGN "AS IS", AND
.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, PACKET DESIGN MAKES NO
.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING
.\" THIS SOFTWARE, INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED
.\" WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
.\" OR NON-INFRINGEMENT.  PACKET DESIGN DOES NOT WARRANT, GUARANTEE,
.\" OR MAKE ANY REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS
.\" OF THE USE OF THIS SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY,
.\" RELIABILITY OR OTHERWISE.  IN NO EVENT SHALL PACKET DESIGN BE
.\" LIABLE FOR ANY DAMAGES RESULTING FROM OR ARISING OUT OF ANY USE
.\" OF THIS SOFTWARE, INCLUDING WITHOUT LIMITATION, ANY DIRECT,
.\" INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, PUNITIVE, OR CONSEQUENTIAL
.\" DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, LOSS OF
.\" USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY THEORY OF
.\" LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
.\" THE USE OF THIS SOFTWARE, EVEN IF PACKET DESIGN IS ADVISED OF
.\" THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" Author: Archie Cobbs <archie@freebsd.org>
.\"
.\" $Id: libpdel.3,v 1.1.1.1 2012/02/21 23:25:53 misho Exp $
.\"
.Dd April 22, 2002
.Dt LIBPDEL 3
.Os
.Sh NAME
.Nm libpdel
.Nd multi-purpose C library for embedded applications
.Sh LIBRARY
PDEL Library (libpdel, \-lpdel)
.Sh DESCRIPTION
The Packet Design Embedded Library (PDEL) is a C library containing
an assorted collection of code useful for developing embedded
applications:
.Pp
.Bl -dash -compact
.It
C data structure run-time introspection library:
.Xr structs 3
.Bl -dash -compact
.It
Support for automated conversion to/from XML
.It
Pre-defined types for most C data structures
.El
.It
Threaded HTTP client/server library:
.Xr http_server 3
.Bl -dash -compact
.It
SSL support
.It
User-definable C "servlets":
.Xr http_servlet 3
.It
Several pre-defined servlets
.It
Support for XML/HTTP and XML-RPC:
.Xr http_xml 3
.El
.It
PPP stack library (FreeBSD only):
.Xr pdel_ppp 3
.Bl -dash -compact
.It
Netgraph(4) based for kernel data packet handling
.It
Servers for PPTP and L2TP
.El
.It
Application configuration framework:
.Xr app_config 3
.It
Heap memory accounting and sanity checking:
.Xr typed_mem 3
.It
File template library:
.Xr tmpl 3
.It
Routines to configure networking interfaces, ARP table,
and routing table (FreeBSD only):
.Xr if_util 3 ,
.Xr route_msg 3 ,
.Xr uroute 3
.It
Logging library:
.Xr alog 3
.Bl -dash -compact
.It
Automated storage into circular file:
.Xr logfile 3
.It
.Xr syslog 3 
compatibile
.El
.It
Generic TCP server:
.Xr tcp_server 3
.It
Generic hash table implementation:
.Xr ghash 3
.It
Generic balanced tree implementation:
.Xr gtree 3
.It
.Vt "FILE *"
enhancements:
.Bl -dash -compact
.It
Generic data "filters":
.Xr filter_fopen 3
.It
MIME boundary input streams:
.Xr boundary_fopen 3
.It
Fixed length input streams:
.Xr count_fopen 3
.It
String buffer input/output streams:
.Xr string_fp 3
.It
Timeout streams:
.Xr timeout_fdopen 3
.It
SSL streams:
.Xr ssl_fp 3
.El
.It
Base-64 encoding/decoding:
.Xr base64 3
.It
Events and actions with automated locking:
.Xr paction 3 ,
.Xr pevent 3
.It
Generalized per-thread variables:
.Xr tinfo 3
.It
Message ports:
.Xr mesg_port 3
.It
Digital signature creation/verification:
.Xr rsa_util_sign 3
.It
Filesystem mounting/unmounting (FreeBSD only):
.Xr fs_mount 3
.It
String quoting/parsing:
.Xr string_enquote 3
.El
.Pp
For more details, see the individual man pages referenced above.
.Sh REQUIREMENTS
Unlike Java, libraries written in C cannot presume a commonly accepted
standard for handling certain issues like threading and heap allocation.
Therefore,
.Nm libpdel
makes certain assumptions which user code must follow.
.Pp
First, all heap memory in
.Nm libpdel
is allocated through the
.Xr typed_mem 3
typed memory system.
Participation by user code in this system is optional, but it
must be done, or not done, consistently.
.Pp
The
.Nm libpdel
library assumes that
.Xr pthread 3
is used for user-level threading.
In general,
.Nm libpdel
objects are not safe to be called simultaneously from separate threads,
or re-entrantly from the same thread, except where explicitly documented.
For example, the application must guarantee serialized access to a
.Xr ghash 3
hash table; the hash table itself does not provide this protection.
.Pp
Some threads that can end up running user code
are subject to cancellation at any cancellation point.
For example, a thread created by an
.Xr http_server 3
object to handle an HTTP request will be canceled if the remote client
closes the TCP connection.
This implies that any user code which could be running under such a
thread must register thread cleanup hooks to release any resources
such as heap memory, mutexes, etc., should the thread be canceled.
.Pp
All
.Nm libpdel
functions are cancel-safe if the thread has cancel type
.Dv PTHREAD_CANCEL_DEFERRED ,
except where noted.
.Pp
Because
.Nm libpdel
in turn depends on other libraries, programs linking with
.Nm libpdel
must also link with these libraries:
.Pp
.Bl -dash -compact
.It
SSL:
.Li "-lssl"
.It
Cryptography:
.Li "-lcrypto"
.It
Netgraph (FreeBSD only):
.Li "-lnetgraph"
.It
RADIUS (FreeBSD only):
.Li "-lradius"
.It
Expat:
.Li "-L/usr/local/lib -lexpat"
.It
Pthreads:
.Li "-pthread"
.Li "(-lpthread"
on Linux)
.El
.Pp
Expat is available as FreeBSD port "textproc/expat2"
(see
.Xr ports 7) .
.Sh SEE ALSO
.Xr alog 3 ,
.Xr app_config 3 ,
.Xr base64 3 ,
.Xr boundary_fopen 3 ,
.Xr count_fopen 3 ,
.Xr filter_fopen 3 ,
.Xr fs_mount 3 ,
.Xr ghash 3 ,
.Xr gtree 3 ,
.Xr http_client 3 ,
.Xr http_server 3 ,
.Xr if_util 3 ,
.Xr logfile 3 ,
.Xr paction 3 ,
.Xr pdel_ppp 3 ,
.Xr pevent 3 ,
.Xr pthread 3 ,
.Xr route_msg 3 ,
.Xr rsa_util_sign 3 ,
.Xr string_enquote 3 ,
.Xr string_fp 3 ,
.Xr structs 3 ,
.Xr tcp_server 3 ,
.Xr timeout_fdopen 3 ,
.Xr tinfo 3 ,
.Xr tmpl 3 ,
.Xr typed_mem 3 ,
.Xr uroute 3
.Rs
.%Q The Open Group
.%R "Single UNIX Specification, Version 2"
.%T "Threads"
.%O "http://www.opengroup.org/onlinepubs/7908799/xsh/threads.html"
.Re
.Rs
.%A James Clark
.%T "Expat XML Parser"
.%O "http://sourceforge.net/projects/expat/"
.Re
.Sh HISTORY
The PDEL library was developed at Packet Design, LLC.
.Dv "http://www.packetdesign.com/"
.Sh AUTHORS
.An Archie Cobbs Aq archie@freebsd.org
.Sh BUGS
Some functionality is only supported under FreeBSD.
.Pp
Please report bugs to the author.