bind9/lib/dns/include/dns/tcpmsg.h

139 lines
3.3 KiB
C

/*
* Copyright (C) 1999 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
#ifndef DNS_TCPMSG_H
#define DNS_TCPMSG_H
#include <isc/buffer.h>
#include <isc/int.h>
#include <isc/socket.h>
typedef struct {
/* private (don't touch!) */
unsigned int magic;
isc_uint16_t size;
isc_buffer_t buffer;
unsigned int maxsize;
isc_mem_t *mctx;
isc_socket_t *sock;
isc_task_t *task;
isc_taskaction_t action;
void *arg;
isc_event_t event;
/* public (read-only) */
isc_result_t result;
isc_sockaddr_t address;
} dns_tcpmsg_t;
void
dns_tcpmsg_init(isc_mem_t *mctx, isc_socket_t *sock, dns_tcpmsg_t *tcpmsg);
/*
* Associate a tcp message state with a given memory context and
* TCP socket.
*
* Requires:
*
* "mctx" and "sock" be non-NULL and valid types.
*
* "sock" be a read/write TCP socket.
*
* "tcpmsg" be non-NULL and an uninitialized or invalidated structure.
*
* Ensures:
*
* "tcpmsg" is a valid structure.
*/
void
dns_tcpmsg_setmaxsize(dns_tcpmsg_t *tcpmsg, unsigned int maxsize);
/*
* Set the maximum packet size to "maxsize"
*
* Requires:
*
* "tcpmsg" be valid.
*
* 512 <= "maxsize" <= 65536
*/
isc_result_t
dns_tcpmsg_readmessage(dns_tcpmsg_t *tcpmsg,
isc_task_t *task, isc_taskaction_t action, void *arg);
/*
* Schedule an event to be delivered when a DNS message is readable, or
* when an error occurs on the socket.
*
* Requires:
*
* "tcpmsg" be valid.
*
* "task", "taskaction", and "arg" be valid.
*
* Returns:
*
* ISC_R_SUCCESS -- no error
* Anything that the isc_socket_recv() call can return. XXXMLG
*
* Notes:
*
* The event delivered is a fully generic event. It will contain no
* actual data. The sender will be a pointer to the dns_tcpmsg_t.
* The result code inside that structure should be checked to see
* what the final result was.
*/
void
dns_tcpmsg_cancelread(dns_tcpmsg_t *tcpmsg);
/*
* Cancel a readmessage() call. The event will still be posted with a
* CANCELED result code.
*
* Requires:
*
* "tcpmsg" be valid.
*/
void
dns_tcpmsg_keepbuffer(dns_tcpmsg_t *tcpmsg, isc_buffer_t *buffer);
/*
* If a dns buffer is to be kept between calls, this function marks the
* internal state-machine buffer as invalid, and copies all the contents
* of the state into "buffer".
*
* Requires:
*
* "tcpmsg" be valid.
*
* "buffer" be non-NULL.
*/
void
dns_tcpmsg_invalidate(dns_tcpmsg_t *tcpmsg);
/*
* Clean up all allocated state, and invalidate the structure.
*
* Requires:
*
* "tcpmsg" be valid.
*
* Ensures:
*
* "tcpmsg" is invalidated and disassociated with all memory contexts,
* sockets, etc.
*/
#endif /* DNS_TCPMSG_H */