summaryrefslogtreecommitdiff
path: root/include/sqfs/predef.h
blob: 32541869899dc7f2ccd86e9673a60ba1e490a1d0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/* SPDX-License-Identifier: LGPL-3.0-or-later */
/*
 * predef.h - This file is part of libsquashfs
 *
 * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
#ifndef SQFS_PREDEF_H
#define SQFS_PREDEF_H

/**
 * @file predef.h
 *
 * @brief Includes forward declarations of data structures,
 *        macros and integer types.
 */

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

#if defined(_WIN32) || defined(__CYGWIN__)
	#ifdef SQFS_BUILDING_DLL
		#if defined(__GNUC__) || defined(__clang__)
			#define SQFS_API __attribute__ ((dllexport))
		#else
			#define SQFS_API __declspec(dllexport)
		#endif
	#else
		#if defined(__GNUC__) || defined(__clang__)
			#define SQFS_API __attribute__ ((dllimport))
		#else
			#define SQFS_API __declspec(dllimport)
		#endif
	#endif

	#define SQFS_INTERNAL
#else
	#if defined(__GNUC__) || defined(__clang__)
		#define SQFS_API __attribute__ ((visibility ("default")))
		#define SQFS_INTERNAL  __attribute__ ((visibility ("hidden")))
	#else
		#define SQFS_API
		#define SQFS_INTERNAL
	#endif
#endif

#ifdef _MSC_VER
	#define SQFS_INLINE __forceinline
#else
	#define SQFS_INLINE __inline__ __attribute__((always_inline))
#endif

typedef uint8_t sqfs_u8;
typedef uint16_t sqfs_u16;
typedef uint32_t sqfs_u32;
typedef uint64_t sqfs_u64;

typedef int8_t sqfs_s8;
typedef int16_t sqfs_s16;
typedef int32_t sqfs_s32;
typedef int64_t sqfs_s64;

typedef struct sqfs_block_processor_t sqfs_block_processor_t;
typedef struct sqfs_compressor_config_t sqfs_compressor_config_t;
typedef struct sqfs_compressor_t sqfs_compressor_t;
typedef struct sqfs_dir_writer_t sqfs_dir_writer_t;
typedef struct sqfs_dir_reader_t sqfs_dir_reader_t;
typedef struct sqfs_id_table_t sqfs_id_table_t;
typedef struct sqfs_meta_reader_t sqfs_meta_reader_t;
typedef struct sqfs_meta_writer_t sqfs_meta_writer_t;
typedef struct sqfs_xattr_reader_t sqfs_xattr_reader_t;
typedef struct sqfs_file_t sqfs_file_t;
typedef struct sqfs_tree_node_t sqfs_tree_node_t;
typedef struct sqfs_data_reader_t sqfs_data_reader_t;
typedef struct sqfs_block_hooks_t sqfs_block_hooks_t;
typedef struct sqfs_xattr_writer_t sqfs_xattr_writer_t;
typedef struct sqfs_frag_table_t sqfs_frag_table_t;
typedef struct sqfs_block_writer_t sqfs_block_writer_t;
typedef struct sqfs_block_writer_stats_t sqfs_block_writer_stats_t;
typedef struct sqfs_block_processor_stats_t sqfs_block_processor_stats_t;
typedef struct sqfs_block_processor_desc_t sqfs_block_processor_desc_t;

typedef struct sqfs_fragment_t sqfs_fragment_t;
typedef struct sqfs_dir_header_t sqfs_dir_header_t;
typedef struct sqfs_dir_entry_t sqfs_dir_entry_t;
typedef struct sqfs_dir_index_t sqfs_dir_index_t;
typedef struct sqfs_inode_t sqfs_inode_t;
typedef struct sqfs_inode_dev_t sqfs_inode_dev_t;
typedef struct sqfs_inode_dev_ext_t sqfs_inode_dev_ext_t;
typedef struct sqfs_inode_ipc_t sqfs_inode_ipc_t;
typedef struct sqfs_inode_ipc_ext_t sqfs_inode_ipc_ext_t;
typedef struct sqfs_inode_slink_t sqfs_inode_slink_t;
typedef struct sqfs_inode_slink_ext_t sqfs_inode_slink_ext_t;
typedef struct sqfs_inode_file_t sqfs_inode_file_t;
typedef struct sqfs_inode_file_ext_t sqfs_inode_file_ext_t;
typedef struct sqfs_inode_dir_t sqfs_inode_dir_t;
typedef struct sqfs_inode_dir_ext_t sqfs_inode_dir_ext_t;
typedef struct sqfs_inode_generic_t sqfs_inode_generic_t;
typedef struct sqfs_super_t sqfs_super_t;
typedef struct sqfs_xattr_entry_t sqfs_xattr_entry_t;
typedef struct sqfs_xattr_value_t sqfs_xattr_value_t;
typedef struct sqfs_xattr_id_t sqfs_xattr_id_t;
typedef struct sqfs_xattr_id_table_t sqfs_xattr_id_table_t;

/**
 * @interface sqfs_object_t
 *
 * @brief Base interface for all libsquashfs in-memory data structures.
 */
typedef struct sqfs_object_t {
	void (*destroy)(struct sqfs_object_t *instance);

	struct sqfs_object_t *(*copy)(const struct sqfs_object_t *orig);
} sqfs_object_t;

/**
 * @brief Destroy an object and free all its memory
 *
 * @memberof sqfs_object_t
 *
 * @param obj A pointer to an object
 */
static SQFS_INLINE void sqfs_destroy(void *obj)
{
	((sqfs_object_t *)obj)->destroy((sqfs_object_t *)obj);
}

/**
 * @brief Create a deep copy of an object if possible.
 *
 * @memberof sqfs_object_t
 *
 * @param obj A pointer to an object
 *
 * @return A pointer to a new object, instantiated from the old on success,
 *         NULL on failure.
 */
static SQFS_INLINE void *sqfs_copy(const void *obj)
{
	if (((sqfs_object_t *)obj)->copy != NULL)
		return ((sqfs_object_t *)obj)->copy((sqfs_object_t *)obj);

	return NULL;
}

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief Free a block of memory created by the squashfs library
 *
 * Some objects in the squashfs library allocate temporary chunks of memory
 * and return pointers to them, with the expectation that the user takes care
 * of freeing them memory again.
 *
 * In the past this worked without hitches, because most sane operating systems
 * have a single, global C library that everything is linked against. On
 * systems like Windows that have a huge fragmentation of runtime libraries
 * this fails, because the library and application can easily end up linked
 * against different runtime libraries, making it impossible for the program
 * to free the memory.
 *
 * To re-create the same situation on Linux, one would have to link a program
 * and the squashfs library dynamically, while linking at least one of them
 * statically against the C runtime, or intentionally linking against two
 * different runtimes.
 *
 * This function mitigates the arising problem by exposing the free() function
 * of the libraries runtime to the application, so it can propperly release
 * memory again to the correct heap.
 *
 * To maintain API/ABI compatibillity, it is guaranteed that for all versions
 * of libsquashfs with major version 1, this function does nothing other than
 * call free() on the C runtime that the library was linked against. If just
 * calling free() works on your system, it will continue to work, and older
 * application will continue to work with newer versions of libsquashfs 1.x.
 * Going forward, new applications using libsquashfs should use this function
 * instead for better portabillity.
 *
 * @param ptr A pointer to a memory block returned by a libsquashfs function.
 */
SQFS_API void sqfs_free(void *ptr);

#ifdef __cplusplus
}
#endif

#endif /* SQFS_PREDEF_H */