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
21 #include <fcntl.h>
22 #include <sys/stat.h>
23 #include <unistd.h>
24
25 #include <media/MidiIoWrapper.h>
26 #include <media/MediaExtractorPluginApi.h>
27
readAt(void * handle,void * buffer,int pos,int size)28 static int readAt(void *handle, void *buffer, int pos, int size) {
29 return ((android::MidiIoWrapper*)handle)->readAt(buffer, pos, size);
30 }
size(void * handle)31 static int size(void *handle) {
32 return ((android::MidiIoWrapper*)handle)->size();
33 }
34
35 namespace android {
36
MidiIoWrapper(const char * path)37 MidiIoWrapper::MidiIoWrapper(const char *path) {
38 ALOGV("MidiIoWrapper(%s)", path);
39 mFd = open(path, O_RDONLY | O_LARGEFILE);
40 mBase = 0;
41 mLength = lseek(mFd, 0, SEEK_END);
42 mDataSource = nullptr;
43 }
44
MidiIoWrapper(int fd,off64_t offset,int64_t size)45 MidiIoWrapper::MidiIoWrapper(int fd, off64_t offset, int64_t size) {
46 ALOGV("MidiIoWrapper(fd=%d)", fd);
47 mFd = fd < 0 ? -1 : dup(fd);
48 mBase = offset;
49 mLength = size;
50 mDataSource = nullptr;
51 }
52
53 class MidiIoWrapper::DataSourceUnwrapper {
54
55 public:
DataSourceUnwrapper(CDataSource * csource)56 explicit DataSourceUnwrapper(CDataSource *csource) {
57 mSource = csource;
58 }
59
~DataSourceUnwrapper()60 virtual ~DataSourceUnwrapper() {}
61
initCheck() const62 virtual status_t initCheck() const { return OK; }
63
64 // Returns the number of bytes read, or -1 on failure. It's not an error if
65 // this returns zero; it just means the given offset is equal to, or
66 // beyond, the end of the source.
readAt(off64_t offset,void * data,size_t size)67 virtual ssize_t readAt(off64_t offset, void *data, size_t size) {
68 return mSource->readAt(mSource->handle, offset, data, size);
69 }
70
71 // May return ERROR_UNSUPPORTED.
getSize(off64_t * size)72 virtual status_t getSize(off64_t *size) {
73 return mSource->getSize(mSource->handle, size);
74 }
75
getUri(char *,size_t)76 virtual bool getUri(char * /*uriString*/, size_t /*bufferSize*/) {
77 return false;
78 }
79
flags()80 virtual uint32_t flags() {
81 return 0;
82 }
83
close()84 virtual void close() {};
85 private:
86 CDataSource *mSource;
87 };
88
MidiIoWrapper(CDataSource * csource)89 MidiIoWrapper::MidiIoWrapper(CDataSource *csource) {
90 ALOGV("MidiIoWrapper(CDataSource)");
91 mFd = -1;
92 mBase = 0;
93 mDataSource = new DataSourceUnwrapper(csource);
94 off64_t l;
95 if (mDataSource->getSize(&l) == OK) {
96 mLength = l;
97 } else {
98 mLength = 0;
99 }
100 }
101
~MidiIoWrapper()102 MidiIoWrapper::~MidiIoWrapper() {
103 ALOGV("~MidiIoWrapper");
104 if (mFd >= 0) {
105 close(mFd);
106 }
107 delete mDataSource;
108 }
109
readAt(void * buffer,int offset,int size)110 int MidiIoWrapper::readAt(void *buffer, int offset, int size) {
111 ALOGV("readAt(%p, %d, %d)", buffer, offset, size);
112
113 if (mDataSource != NULL) {
114 return mDataSource->readAt(offset, buffer, size);
115 }
116 if (mFd < 0) {
117 errno = EBADF;
118 return -1; // as per failed read.
119 }
120 lseek(mFd, mBase + offset, SEEK_SET);
121 if (offset + size > mLength) {
122 size = mLength - offset;
123 }
124 return read(mFd, buffer, size);
125 }
126
size()127 int MidiIoWrapper::size() {
128 ALOGV("size() = %d", int(mLength));
129 return mLength;
130 }
131
getLocator()132 EAS_FILE_LOCATOR MidiIoWrapper::getLocator() {
133 mEasFile.handle = this;
134 mEasFile.readAt = ::readAt;
135 mEasFile.size = ::size;
136 return &mEasFile;
137 }
138
139 } // namespace android
140