xref: /onnv-gate/usr/src/cmd/sort/common/streams_array.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate #include "streams_array.h"
30*0Sstevel@tonic-gate #include "streams_common.h"
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate /*
33*0Sstevel@tonic-gate  * Single-byte character memory map-based streams implementation
34*0Sstevel@tonic-gate  */
35*0Sstevel@tonic-gate 
36*0Sstevel@tonic-gate static int
stream_array_prime(stream_t * str)37*0Sstevel@tonic-gate stream_array_prime(stream_t *str)
38*0Sstevel@tonic-gate {
39*0Sstevel@tonic-gate 	ASSERT((str->s_status & STREAM_SOURCE_MASK) == STREAM_ARRAY);
40*0Sstevel@tonic-gate 
41*0Sstevel@tonic-gate 	str->s_type.LA.s_cur_index = MIN(0, str->s_type.LA.s_array_size - 1);
42*0Sstevel@tonic-gate 	if (str->s_type.LA.s_cur_index >= 0)
43*0Sstevel@tonic-gate 		copy_line_rec(
44*0Sstevel@tonic-gate 		    str->s_type.LA.s_array[str->s_type.LA.s_cur_index],
45*0Sstevel@tonic-gate 		    &str->s_current);
46*0Sstevel@tonic-gate 	else {
47*0Sstevel@tonic-gate 		stream_set(str, STREAM_EOS_REACHED);
48*0Sstevel@tonic-gate 		stream_unset(str, STREAM_PRIMED);
49*0Sstevel@tonic-gate 		return (PRIME_FAILED_EMPTY_FILE);
50*0Sstevel@tonic-gate 	}
51*0Sstevel@tonic-gate 
52*0Sstevel@tonic-gate 	stream_set(str, STREAM_PRIMED);
53*0Sstevel@tonic-gate 
54*0Sstevel@tonic-gate 	return (PRIME_SUCCEEDED);
55*0Sstevel@tonic-gate }
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate static ssize_t
stream_array_fetch(stream_t * str)58*0Sstevel@tonic-gate stream_array_fetch(stream_t *str)
59*0Sstevel@tonic-gate {
60*0Sstevel@tonic-gate 	ASSERT(str->s_status & STREAM_OPEN);
61*0Sstevel@tonic-gate 	ASSERT(str->s_type.LA.s_cur_index < str->s_type.LA.s_array_size);
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate 	if (++str->s_type.LA.s_cur_index == str->s_type.LA.s_array_size - 1)
64*0Sstevel@tonic-gate 		stream_set(str, STREAM_EOS_REACHED);
65*0Sstevel@tonic-gate 
66*0Sstevel@tonic-gate 	copy_line_rec(str->s_type.LA.s_array[str->s_type.LA.s_cur_index],
67*0Sstevel@tonic-gate 	    &str->s_current);
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate 	return (NEXT_LINE_COMPLETE);
70*0Sstevel@tonic-gate }
71*0Sstevel@tonic-gate 
72*0Sstevel@tonic-gate /*ARGSUSED*/
73*0Sstevel@tonic-gate static int
stream_array_is_closable(stream_t * str)74*0Sstevel@tonic-gate stream_array_is_closable(stream_t *str)
75*0Sstevel@tonic-gate {
76*0Sstevel@tonic-gate 	/*
77*0Sstevel@tonic-gate 	 * Array streams are not closable.  That is, there is no open file
78*0Sstevel@tonic-gate 	 * descriptor directly associated with an array stream.
79*0Sstevel@tonic-gate 	 */
80*0Sstevel@tonic-gate 	return (0);
81*0Sstevel@tonic-gate }
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate static int
stream_array_close(stream_t * str)84*0Sstevel@tonic-gate stream_array_close(stream_t *str)
85*0Sstevel@tonic-gate {
86*0Sstevel@tonic-gate 	stream_unset(str, STREAM_OPEN | STREAM_PRIMED);
87*0Sstevel@tonic-gate 
88*0Sstevel@tonic-gate 	return (1);
89*0Sstevel@tonic-gate }
90*0Sstevel@tonic-gate 
91*0Sstevel@tonic-gate static int
stream_array_free(stream_t * str)92*0Sstevel@tonic-gate stream_array_free(stream_t *str)
93*0Sstevel@tonic-gate {
94*0Sstevel@tonic-gate 	/*
95*0Sstevel@tonic-gate 	 * It's now safe for us to close the various streams backing the array
96*0Sstevel@tonic-gate 	 * stream's data.
97*0Sstevel@tonic-gate 	 */
98*0Sstevel@tonic-gate 	stream_unset(str, STREAM_PRIMED | STREAM_NOT_FREEABLE);
99*0Sstevel@tonic-gate 
100*0Sstevel@tonic-gate 	return (1);
101*0Sstevel@tonic-gate }
102*0Sstevel@tonic-gate 
103*0Sstevel@tonic-gate static int
stream_array_eos(stream_t * str)104*0Sstevel@tonic-gate stream_array_eos(stream_t *str)
105*0Sstevel@tonic-gate {
106*0Sstevel@tonic-gate 	int retval = 0;
107*0Sstevel@tonic-gate 
108*0Sstevel@tonic-gate 	if (str == NULL || str->s_status & STREAM_EOS_REACHED)
109*0Sstevel@tonic-gate 		return (1);
110*0Sstevel@tonic-gate 
111*0Sstevel@tonic-gate 	if (str->s_type.LA.s_cur_index + 1 >= str->s_type.LA.s_array_size) {
112*0Sstevel@tonic-gate 		retval = 1;
113*0Sstevel@tonic-gate 		stream_set(str, STREAM_EOS_REACHED);
114*0Sstevel@tonic-gate 	}
115*0Sstevel@tonic-gate 
116*0Sstevel@tonic-gate 	return (retval);
117*0Sstevel@tonic-gate }
118*0Sstevel@tonic-gate 
119*0Sstevel@tonic-gate /*ARGSUSED*/
120*0Sstevel@tonic-gate static void
stream_array_release_line(stream_t * str)121*0Sstevel@tonic-gate stream_array_release_line(stream_t *str)
122*0Sstevel@tonic-gate {
123*0Sstevel@tonic-gate }
124*0Sstevel@tonic-gate 
125*0Sstevel@tonic-gate const stream_ops_t stream_array_ops = {
126*0Sstevel@tonic-gate 	stream_array_is_closable,
127*0Sstevel@tonic-gate 	stream_array_close,
128*0Sstevel@tonic-gate 	stream_array_eos,
129*0Sstevel@tonic-gate 	stream_array_fetch,
130*0Sstevel@tonic-gate 	NULL,
131*0Sstevel@tonic-gate 	stream_array_free,
132*0Sstevel@tonic-gate 	NULL,
133*0Sstevel@tonic-gate 	stream_array_prime,
134*0Sstevel@tonic-gate 	NULL,
135*0Sstevel@tonic-gate 	stream_array_release_line,
136*0Sstevel@tonic-gate 	NULL,
137*0Sstevel@tonic-gate 	NULL
138*0Sstevel@tonic-gate };
139