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1.1 ! misho 1: /* buffer.h ! 2: ! 3: Definitions for the object management API protocol buffering... */ ! 4: ! 5: /* ! 6: * Copyright (c) 2004,2009 by Internet Systems Consortium, Inc. ("ISC") ! 7: * Copyright (c) 1996-2003 by Internet Software Consortium ! 8: * ! 9: * Permission to use, copy, modify, and distribute this software for any ! 10: * purpose with or without fee is hereby granted, provided that the above ! 11: * copyright notice and this permission notice appear in all copies. ! 12: * ! 13: * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES ! 14: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF ! 15: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ! 16: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES ! 17: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ! 18: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT ! 19: * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. ! 20: * ! 21: * Internet Systems Consortium, Inc. ! 22: * 950 Charter Street ! 23: * Redwood City, CA 94063 ! 24: * <info@isc.org> ! 25: * https://www.isc.org/ ! 26: * ! 27: * This software has been written for Internet Systems Consortium ! 28: * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc. ! 29: * To learn more about Internet Systems Consortium, see ! 30: * ``https://www.isc.org/''. To learn more about Vixie Enterprises, ! 31: * see ``http://www.vix.com''. To learn more about Nominum, Inc., see ! 32: * ``http://www.nominum.com''. ! 33: */ ! 34: ! 35: /* OMAPI buffers are ring buffers, which means that the beginning of the ! 36: buffer and the end of the buffer chase each other around. As long as ! 37: the tail never catches up to the head, there's room in the buffer for ! 38: data. ! 39: ! 40: - If the tail and the head are equal, the buffer is empty. ! 41: ! 42: - If the tail is less than the head, the contents of the buffer ! 43: are the bytes from the head to the end of buffer, and in addition, ! 44: the bytes between the beginning of the buffer and the tail, not ! 45: including the byte addressed by the tail. ! 46: ! 47: - If the tail is greater than the head, then the buffer contains ! 48: valid bytes starting with the byte addressed by the head, and ! 49: ending with the byte before the byte addressed by the tail. ! 50: ! 51: There will always be at least one byte of waste, because the tail can't ! 52: increase so that it's equal to the head (that would represent an empty ! 53: buffer. */ ! 54: #define OMAPI_BUF_SIZE 4048 ! 55: typedef struct _omapi_buffer { ! 56: struct _omapi_buffer *next; /* Buffers can be chained. */ ! 57: u_int32_t refcnt; /* Buffers are reference counted. */ ! 58: u_int16_t head, tail; /* Buffers are organized in a ring. */ ! 59: char buf [OMAPI_BUF_SIZE]; /* The actual buffer is included in ! 60: the buffer data structure. */ ! 61: } omapi_buffer_t; ! 62: ! 63: #define BUFFER_BYTES_FREE(x) \ ! 64: ((x) -> tail > (x) -> head \ ! 65: ? sizeof ((x) -> buf) - ((x) -> tail - (x) -> head) \ ! 66: : (x) -> head - (x) -> tail) ! 67: ! 68: #define BYTES_IN_BUFFER(x) \ ! 69: ((x) -> tail > (x) -> head \ ! 70: ? (x) -> tail - (x) -> head - 1 \ ! 71: : sizeof ((x) -> buf) - ((x) -> head - (x) -> tail) - 1) ! 72: ! 73: isc_result_t omapi_connection_require (omapi_object_t *, unsigned); ! 74: isc_result_t omapi_connection_copyout (unsigned char *, ! 75: omapi_object_t *, unsigned); ! 76: isc_result_t omapi_connection_copyin (omapi_object_t *, ! 77: const unsigned char *, unsigned); ! 78: isc_result_t omapi_connection_flush (omapi_object_t *); ! 79: isc_result_t omapi_connection_get_uint32 (omapi_object_t *, u_int32_t *); ! 80: isc_result_t omapi_connection_put_uint32 (omapi_object_t *, u_int32_t); ! 81: isc_result_t omapi_connection_get_uint16 (omapi_object_t *, u_int16_t *); ! 82: isc_result_t omapi_connection_put_uint16 (omapi_object_t *, u_int32_t); ! 83: