1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17
18#ifndef ANDROID_ASSET_MANAGER_H
19#define ANDROID_ASSET_MANAGER_H
20
21#include <sys/types.h>
22
23#ifdef __cplusplus
24extern "C" {
25#endif
26
27struct AAssetManager;
28typedef struct AAssetManager AAssetManager;
29
30struct AAssetDir;
31typedef struct AAssetDir AAssetDir;
32
33struct AAsset;
34typedef struct AAsset AAsset;
35
36/* Available modes for opening assets */
37enum {
38    AASSET_MODE_UNKNOWN      = 0,
39    AASSET_MODE_RANDOM       = 1,
40    AASSET_MODE_STREAMING    = 2,
41    AASSET_MODE_BUFFER       = 3
42};
43
44
45/**
46 * Open the named directory within the asset hierarchy.  The directory can then
47 * be inspected with the AAssetDir functions.  To open the top-level directory,
48 * pass in "" as the dirName.
49 *
50 * The object returned here should be freed by calling AAssetDir_close().
51 */
52AAssetDir* AAssetManager_openDir(AAssetManager* mgr, const char* dirName);
53
54/**
55 * Open an asset.
56 *
57 * The object returned here should be freed by calling AAsset_close().
58 */
59AAsset* AAssetManager_open(AAssetManager* mgr, const char* filename, int mode);
60
61/**
62 * Iterate over the files in an asset directory.  A NULL string is returned
63 * when all the file names have been returned.
64 *
65 * The returned file name is suitable for passing to AAssetManager_open().
66 *
67 * The string returned here is owned by the AssetDir implementation and is not
68 * guaranteed to remain valid if any other calls are made on this AAssetDir
69 * instance.
70 */
71const char* AAssetDir_getNextFileName(AAssetDir* assetDir);
72
73/**
74 * Reset the iteration state of AAssetDir_getNextFileName() to the beginning.
75 */
76void AAssetDir_rewind(AAssetDir* assetDir);
77
78/**
79 * Close an opened AAssetDir, freeing any related resources.
80 */
81void AAssetDir_close(AAssetDir* assetDir);
82
83/**
84 * Attempt to read 'count' bytes of data from the current offset.
85 *
86 * Returns the number of bytes read, zero on EOF, or < 0 on error.
87 */
88int AAsset_read(AAsset* asset, void* buf, size_t count);
89
90/**
91 * Seek to the specified offset within the asset data.  'whence' uses the
92 * same constants as lseek()/fseek().
93 *
94 * Returns the new position on success, or (off_t) -1 on error.
95 */
96off_t AAsset_seek(AAsset* asset, off_t offset, int whence);
97
98/**
99 * Close the asset, freeing all associated resources.
100 */
101void AAsset_close(AAsset* asset);
102
103/**
104 * Get a pointer to a buffer holding the entire contents of the assset.
105 *
106 * Returns NULL on failure.
107 */
108const void* AAsset_getBuffer(AAsset* asset);
109
110/**
111 * Report the total size of the asset data.
112 */
113off_t AAsset_getLength(AAsset* asset);
114
115/**
116 * Report the total amount of asset data that can be read from the current position.
117 */
118off_t AAsset_getRemainingLength(AAsset* asset);
119
120/**
121 * Open a new file descriptor that can be used to read the asset data.
122 *
123 * Returns < 0 if direct fd access is not possible (for example, if the asset is
124 * compressed).
125 */
126int AAsset_openFileDescriptor(AAsset* asset, off_t* outStart, off_t* outLength);
127
128/**
129 * Returns whether this asset's internal buffer is allocated in ordinary RAM (i.e. not
130 * mmapped).
131 */
132int AAsset_isAllocated(AAsset* asset);
133
134
135
136#ifdef __cplusplus
137};
138#endif
139
140#endif      // ANDROID_ASSET_MANAGER_H
141