MidiIoWrapper.cpp revision 13b97d6ece762cd96a7c3d3e3d60583104d1c0bc 
1/*
2 * Copyright (C) 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//#define LOG_NDEBUG 0
18#define LOG_TAG "MidiIoWrapper"
19#include <utils/Log.h>
20#include <utils/RefBase.h>
21
22#include <sys/stat.h>
23#include <fcntl.h>
24
25#include "media/MidiIoWrapper.h"
26
27static int readAt(void *handle, void *buffer, int pos, int size) {
28    return ((android::MidiIoWrapper*)handle)->readAt(buffer, pos, size);
29}
30static int size(void *handle) {
31    return ((android::MidiIoWrapper*)handle)->size();
32}
33
34namespace android {
35
36MidiIoWrapper::MidiIoWrapper(const char *path) {
37    ALOGV("MidiIoWrapper(%s)", path);
38    mFd = open(path, O_RDONLY | O_LARGEFILE);
39    mBase = 0;
40    mLength = lseek(mFd, 0, SEEK_END);
41}
42
43MidiIoWrapper::MidiIoWrapper(int fd, off64_t offset, int64_t size) {
44    ALOGV("MidiIoWrapper(fd=%d)", fd);
45    mFd = dup(fd);
46    mBase = offset;
47    mLength = size;
48}
49
50MidiIoWrapper::MidiIoWrapper(const sp<DataSource> &source) {
51    ALOGV("MidiIoWrapper(DataSource)");
52    mFd = -1;
53    mDataSource = source;
54    off64_t l;
55    if (mDataSource->getSize(&l) == OK) {
56        mLength = l;
57    } else {
58        mLength = 0;
59    }
60}
61
62MidiIoWrapper::~MidiIoWrapper() {
63    ALOGV("~MidiIoWrapper");
64    close(mFd);
65}
66
67int MidiIoWrapper::readAt(void *buffer, int offset, int size) {
68    ALOGV("readAt(%p, %d, %d)", buffer, offset, size);
69
70    if (mDataSource != NULL) {
71        return mDataSource->readAt(offset, buffer, size);
72    }
73    lseek(mFd, mBase + offset, SEEK_SET);
74    if (offset + size > mLength) {
75        size = mLength - offset;
76    }
77    return read(mFd, buffer, size);
78}
79
80int MidiIoWrapper::size() {
81    ALOGV("size() = %d", int(mLength));
82    return mLength;
83}
84
85EAS_FILE_LOCATOR MidiIoWrapper::getLocator() {
86    mEasFile.handle = this;
87    mEasFile.readAt = ::readAt;
88    mEasFile.size = ::size;
89    return &mEasFile;
90}
91
92}  // namespace android
93