1/*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * Copyright (c) 2010-2011 Michihiro NAKAJIMA
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include "archive_platform.h"
28__FBSDID("$FreeBSD$");
29
30#include "archive.h"
31#include "archive_entry.h"
32#include "archive_private.h"
33#include "archive_entry_private.h"
34
35/*
36 * sparse handling
37 */
38
39void
40archive_entry_sparse_clear(struct archive_entry *entry)
41{
42	struct ae_sparse *sp;
43
44	while (entry->sparse_head != NULL) {
45		sp = entry->sparse_head->next;
46		free(entry->sparse_head);
47		entry->sparse_head = sp;
48	}
49	entry->sparse_tail = NULL;
50}
51
52void
53archive_entry_sparse_add_entry(struct archive_entry *entry,
54	la_int64_t offset, la_int64_t length)
55{
56	struct ae_sparse *sp;
57
58	if (offset < 0 || length < 0)
59		/* Invalid value */
60		return;
61	if (offset > INT64_MAX - length ||
62	    offset + length > archive_entry_size(entry))
63		/* A value of "length" parameter is too large. */
64		return;
65	if ((sp = entry->sparse_tail) != NULL) {
66		if (sp->offset + sp->length > offset)
67			/* Invalid value. */
68			return;
69		if (sp->offset + sp->length == offset) {
70			if (sp->offset + sp->length + length < 0)
71				/* A value of "length" parameter is
72				 * too large. */
73				return;
74			/* Expand existing sparse block size. */
75			sp->length += length;
76			return;
77		}
78	}
79
80	if ((sp = (struct ae_sparse *)malloc(sizeof(*sp))) == NULL)
81		/* XXX Error XXX */
82		return;
83
84	sp->offset = offset;
85	sp->length = length;
86	sp->next = NULL;
87
88	if (entry->sparse_head == NULL)
89		entry->sparse_head = entry->sparse_tail = sp;
90	else {
91		/* Add a new sparse block to the tail of list. */
92		if (entry->sparse_tail != NULL)
93			entry->sparse_tail->next = sp;
94		entry->sparse_tail = sp;
95	}
96}
97
98
99/*
100 * returns number of the sparse entries
101 */
102int
103archive_entry_sparse_count(struct archive_entry *entry)
104{
105	struct ae_sparse *sp;
106	int count = 0;
107
108	for (sp = entry->sparse_head; sp != NULL; sp = sp->next)
109		count++;
110
111	/*
112	 * Sanity check if this entry is exactly sparse.
113	 * If amount of sparse blocks is just one and it indicates the whole
114	 * file data, we should remove it and return zero.
115	 */
116	if (count == 1) {
117		sp = entry->sparse_head;
118		if (sp->offset == 0 &&
119		    sp->length >= archive_entry_size(entry)) {
120			count = 0;
121			archive_entry_sparse_clear(entry);
122		}
123	}
124
125	return (count);
126}
127
128int
129archive_entry_sparse_reset(struct archive_entry * entry)
130{
131	entry->sparse_p = entry->sparse_head;
132
133	return archive_entry_sparse_count(entry);
134}
135
136int
137archive_entry_sparse_next(struct archive_entry * entry,
138	la_int64_t *offset, la_int64_t *length)
139{
140	if (entry->sparse_p) {
141		*offset = entry->sparse_p->offset;
142		*length = entry->sparse_p->length;
143
144		entry->sparse_p = entry->sparse_p->next;
145
146		return (ARCHIVE_OK);
147	} else {
148		*offset = 0;
149		*length = 0;
150		return (ARCHIVE_WARN);
151	}
152}
153
154/*
155 * end of sparse handling
156 */
157