1 /*
2  * Copyright 2014 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 #ifndef IMG_UTILS_FILE_INPUT_H
18 #define IMG_UTILS_FILE_INPUT_H
19 
20 #include <img_utils/Input.h>
21 
22 #include <cutils/compiler.h>
23 #include <utils/Errors.h>
24 #include <utils/String8.h>
25 #include <stdio.h>
26 #include <stdint.h>
27 
28 namespace android {
29 namespace img_utils {
30 
31 /**
32  * Utility class for reading from a file.
33  */
34 class ANDROID_API FileInput : public Input {
35     public:
36         /**
37          * Create a file input for the given path.
38          */
39         explicit FileInput(String8 path);
40 
41         virtual ~FileInput();
42 
43         /**
44          * Open a file descriptor to the path given in the constructor.
45          *
46          * Returns OK on success, or a negative error code.
47          */
48         virtual status_t open();
49 
50         /**
51          * Read bytes from the file into the given buffer.  At most, the number
52          * of bytes given in the count argument will be read.  Bytes will be written
53          * into the given buffer starting at the index given in the offset argument.
54          *
55          * Returns the number of bytes read, or NOT_ENOUGH_DATA if at the end of the file.  If an
56          * error has occurred, this will return a negative error code other than NOT_ENOUGH_DATA.
57          */
58         virtual ssize_t read(uint8_t* buf, size_t offset, size_t count);
59 
60         /**
61          * Close the file descriptor to the path given in the constructor.
62          *
63          * Returns OK on success, or a negative error code.
64          */
65         virtual status_t close();
66     private:
67         FILE *mFp;
68         String8 mPath;
69         bool mOpen;
70 };
71 
72 } /*namespace img_utils*/
73 } /*namespace android*/
74 
75 
76 #endif /*IMG_UTILS_INPUT_H*/
77