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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 .\" .\" $Id: http_servlet_xml.3,v 1.1.1.1 2012/02/21 23:25:53 misho Exp $ .\" .Dd April 22, 2002 .Dt HTTP_SERVLET_XML 3 .Os .Sh NAME .Nm http_servlet_xml .Nd HTTP servlet for XML requests .Sh LIBRARY PDEL Library (libpdel, \-lpdel) .Sh SYNOPSIS .In sys/types.h .In stdio.h .In netinet/in.h .In openssl/ssl.h .In pdel/http/http_defs.h .In pdel/http/http_server.h .In pdel/http/servlet/xml.h .Ft "struct http_servlet *" .Fn http_servlet_xml_create "const struct http_servlet_xml_info *info" "void *arg" "void (*destroy)(void *)" .Sh DESCRIPTION .Fn http_servlet_xml_create creates a servlet that receives HTTP requests optionally containing XML and sends back XML responses. The request and response data are automatically converted to and from native binary format using the .Xr structs 3 library. .Pp This servlet is basically acts as glue between the .Xr http_servlet 3 API and the .Xr structs_xml_input 3 and .Xr structs_xml_output 3 library routines. The net result is the ability to send and receive arbitrary data structures between two machines using XML over HTTP. .Pp The incoming HTTP request is expected to either be a .Dq GET or .Dq POST , in the latter case with a request body containing XML. The incoming content type is ignored. The response has content type .Dq text/xml and contains XML. .Pp The .Fa arg is an opaque user cookie. When the servlet is destroyed, if .Fa destroy is not .Dv NULL , it will be invoked with .Fa arg as its parameter. .Pp .Fa info is a pointer to a .Li "struct http_servlet_xml_info" : .Pp .Bd -literal -compact -offset 3n typedef void *http_servlet_xml_handler_t(void *arg, struct http_request *req, const void *payload, const char *pattrs, char **rattrsp, const char *mtype); struct http_servlet_xml_info { http_servlet_xml_handler_t *handler; /* user handler */ const char *ptag; /* payload doc elem */ const struct structs_type *ptype; /* payload type */ const char *rtag; /* reply doc elem */ const struct structs_type *rtype; /* reply type */ u_char allow_post; /* allow POST */ u_char allow_get; /* allow GET */ http_logger_t *logger; /* loggging function */ int flags; /* output flags */ }; .Ed .Pp The .Fa handler is the user routine invoked for each HTTP request (see below). .Fa ptag is the XML document tag for incoming requests. .Fa ptype is the .Xr structs 3 type for the payload data. Incoming requests that don't match .Fa ptag and .Fa ptype are rejected. .Pp Similarly, .Fa rtag is the XML document tag for responses and .Fa rtype is the .Xr structs 3 type for the data returned by .Fn handler . .Pp The .Fa allow_post and .Fa allow_get flags select which of .Dq GET and/or .Dq POST queries are allowed. If .Fa allow_post is zero, then .Fa ptag and .Fa ptype are ignored. .Pp The .Fa logger is a logging function whose type is defined in .Xr http_server 3 . .Pp .Fa flags controls how XML responses are generated; this value is passed unaltered to .Xr structs_xml_output 3 . .Pp When .Fn handler is invoked, .Fa arg is the opqaue cookie supplied to .Fn http_servlet_xml_create , and .Fa req is the .Xr http_request 3 object. .Fa payload and .Fa pattrs will be .Dv NULL for a .Dq GET request, otherwise .Fa payload will point to the received data in native binary format. .Fn handler should not free this data. .Pp .Fa pattrs , if not .Dv NULL , points to the top level XML attributes in the request. The attributes are stored as a single sequence of concatenated pairs: name, '\\0', value, '\\0', name, '\\0', value, etc., terminated with a final (extra) '\\0'. .Pp If top level XML attributes are desired in the response, .Fa "*rattrsp" should be set to a similarly concatenated list of name, value pairs allocated with .Xr typed_mem 3 type .Fa mtype . .Pp .Fn handler should return a pointer to the reply data in native binary format, in a region of memory allocated with .Xr typed_mem 3 type .Fa mtype . If there was an error, .Fn handler should return .Dv NULL and set .Va errno appropriately. .Pp Since it's running as a servlet, the thread executing .Fn handler may be canceled at any cancellation point. .Fn handler should be written so as to not leak resources if this happens. .Sh RETURN VALUES On failure, .Fn http_servlet_xml_create returns .Dv NULL and sets .Va errno to an appropriate value. .Sh SEE ALSO .Xr http_request 3 , .Xr http_response 3 , .Xr http_server 3 , .Xr http_servlet 3 , .Xr http_servlet_xmlrpc 3 , .Xr http_xml 3 , .Xr libpdel 3 , .Xr structs 3 , .Xr typed_mem 3 .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 .Fn http_servlet_xml_create copies all information in .Fa info except the .Xr structs 3 types pointed to by .Fa ptype and .Fa rtype , so these must remain valid for the lifetime of the servlet. Typically .Xr structs 3 types are stored in static variables, so this is not usually a problem.