1 /*
2  * Copyright (C) 2009 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 #include <media/stagefright/foundation/ADebug.h>
18 #include <media/stagefright/FileSource.h>
19 #include <sys/types.h>
20 #include <unistd.h>
21 #include <sys/types.h>
22 #include <sys/stat.h>
23 #include <fcntl.h>
24 
25 namespace android {
26 
FileSource(const char * filename)27 FileSource::FileSource(const char *filename)
28     : mFd(-1),
29       mOffset(0),
30       mLength(-1),
31       mDecryptHandle(NULL),
32       mDrmManagerClient(NULL),
33       mDrmBufOffset(0),
34       mDrmBufSize(0),
35       mDrmBuf(NULL){
36 
37     mFd = open(filename, O_LARGEFILE | O_RDONLY);
38 
39     if (mFd >= 0) {
40         mLength = lseek64(mFd, 0, SEEK_END);
41     } else {
42         ALOGE("Failed to open file '%s'. (%s)", filename, strerror(errno));
43     }
44 }
45 
FileSource(int fd,int64_t offset,int64_t length)46 FileSource::FileSource(int fd, int64_t offset, int64_t length)
47     : mFd(fd),
48       mOffset(offset),
49       mLength(length),
50       mDecryptHandle(NULL),
51       mDrmManagerClient(NULL),
52       mDrmBufOffset(0),
53       mDrmBufSize(0),
54       mDrmBuf(NULL){
55     CHECK(offset >= 0);
56     CHECK(length >= 0);
57 }
58 
~FileSource()59 FileSource::~FileSource() {
60     if (mFd >= 0) {
61         close(mFd);
62         mFd = -1;
63     }
64 
65     if (mDrmBuf != NULL) {
66         delete[] mDrmBuf;
67         mDrmBuf = NULL;
68     }
69 
70     if (mDecryptHandle != NULL) {
71         // To release mDecryptHandle
72         CHECK(mDrmManagerClient);
73         mDrmManagerClient->closeDecryptSession(mDecryptHandle);
74         mDecryptHandle = NULL;
75     }
76 
77     if (mDrmManagerClient != NULL) {
78         delete mDrmManagerClient;
79         mDrmManagerClient = NULL;
80     }
81 }
82 
initCheck() const83 status_t FileSource::initCheck() const {
84     return mFd >= 0 ? OK : NO_INIT;
85 }
86 
readAt(off64_t offset,void * data,size_t size)87 ssize_t FileSource::readAt(off64_t offset, void *data, size_t size) {
88     if (mFd < 0) {
89         return NO_INIT;
90     }
91 
92     Mutex::Autolock autoLock(mLock);
93 
94     if (mLength >= 0) {
95         if (offset >= mLength) {
96             return 0;  // read beyond EOF.
97         }
98         int64_t numAvailable = mLength - offset;
99         if ((int64_t)size > numAvailable) {
100             size = numAvailable;
101         }
102     }
103 
104     if (mDecryptHandle != NULL && DecryptApiType::CONTAINER_BASED
105             == mDecryptHandle->decryptApiType) {
106         return readAtDRM(offset, data, size);
107    } else {
108         off64_t result = lseek64(mFd, offset + mOffset, SEEK_SET);
109         if (result == -1) {
110             ALOGE("seek to %lld failed", offset + mOffset);
111             return UNKNOWN_ERROR;
112         }
113 
114         return ::read(mFd, data, size);
115     }
116 }
117 
getSize(off64_t * size)118 status_t FileSource::getSize(off64_t *size) {
119     Mutex::Autolock autoLock(mLock);
120 
121     if (mFd < 0) {
122         return NO_INIT;
123     }
124 
125     *size = mLength;
126 
127     return OK;
128 }
129 
DrmInitialization(const char * mime)130 sp<DecryptHandle> FileSource::DrmInitialization(const char *mime) {
131     if (mDrmManagerClient == NULL) {
132         mDrmManagerClient = new DrmManagerClient();
133     }
134 
135     if (mDrmManagerClient == NULL) {
136         return NULL;
137     }
138 
139     if (mDecryptHandle == NULL) {
140         mDecryptHandle = mDrmManagerClient->openDecryptSession(
141                 mFd, mOffset, mLength, mime);
142     }
143 
144     if (mDecryptHandle == NULL) {
145         delete mDrmManagerClient;
146         mDrmManagerClient = NULL;
147     }
148 
149     return mDecryptHandle;
150 }
151 
getDrmInfo(sp<DecryptHandle> & handle,DrmManagerClient ** client)152 void FileSource::getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client) {
153     handle = mDecryptHandle;
154 
155     *client = mDrmManagerClient;
156 }
157 
readAtDRM(off64_t offset,void * data,size_t size)158 ssize_t FileSource::readAtDRM(off64_t offset, void *data, size_t size) {
159     size_t DRM_CACHE_SIZE = 1024;
160     if (mDrmBuf == NULL) {
161         mDrmBuf = new unsigned char[DRM_CACHE_SIZE];
162     }
163 
164     if (mDrmBuf != NULL && mDrmBufSize > 0 && (offset + mOffset) >= mDrmBufOffset
165             && (offset + mOffset + size) <= (mDrmBufOffset + mDrmBufSize)) {
166         /* Use buffered data */
167         memcpy(data, (void*)(mDrmBuf+(offset+mOffset-mDrmBufOffset)), size);
168         return size;
169     } else if (size <= DRM_CACHE_SIZE) {
170         /* Buffer new data */
171         mDrmBufOffset =  offset + mOffset;
172         mDrmBufSize = mDrmManagerClient->pread(mDecryptHandle, mDrmBuf,
173                 DRM_CACHE_SIZE, offset + mOffset);
174         if (mDrmBufSize > 0) {
175             int64_t dataRead = 0;
176             dataRead = size > mDrmBufSize ? mDrmBufSize : size;
177             memcpy(data, (void*)mDrmBuf, dataRead);
178             return dataRead;
179         } else {
180             return mDrmBufSize;
181         }
182     } else {
183         /* Too big chunk to cache. Call DRM directly */
184         return mDrmManagerClient->pread(mDecryptHandle, data, size, offset + mOffset);
185     }
186 }
187 }  // namespace android
188