FileSource.cpp revision d49dbd6b625cddb82f3f7bbeac62d48ef338ef0f 
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//#define LOG_NDEBUG 0
18#define LOG_TAG "FileSource"
19#include <utils/Log.h>
20
21#include <media/stagefright/foundation/ADebug.h>
22#include <media/stagefright/FileSource.h>
23#include <media/stagefright/Utils.h>
24#include <private/android_filesystem_config.h>
25#include <sys/types.h>
26#include <unistd.h>
27#include <sys/types.h>
28#include <sys/stat.h>
29#include <fcntl.h>
30
31namespace android {
32
33FileSource::FileSource(const char *filename)
34    : mFd(-1),
35      mOffset(0),
36      mLength(-1),
37      mName("<null>"),
38      mDecryptHandle(NULL),
39      mDrmManagerClient(NULL),
40      mDrmBufOffset(0),
41      mDrmBufSize(0),
42      mDrmBuf(NULL){
43
44    if (filename) {
45        mName = String8::format("FileSource(%s)", filename);
46    }
47    ALOGV("%s", filename);
48    mFd = open(filename, O_LARGEFILE | O_RDONLY);
49
50    if (mFd >= 0) {
51        mLength = lseek64(mFd, 0, SEEK_END);
52    } else {
53        ALOGE("Failed to open file '%s'. (%s)", filename, strerror(errno));
54    }
55}
56
57FileSource::FileSource(int fd, int64_t offset, int64_t length)
58    : mFd(fd),
59      mOffset(offset),
60      mLength(length),
61      mName("<null>"),
62      mDecryptHandle(NULL),
63      mDrmManagerClient(NULL),
64      mDrmBufOffset(0),
65      mDrmBufSize(0),
66      mDrmBuf(NULL) {
67    ALOGV("fd=%d (%s), offset=%lld, length=%lld",
68            fd, nameForFd(fd).c_str(), (long long) offset, (long long) length);
69
70    if (mOffset < 0) {
71        mOffset = 0;
72    }
73    if (mLength < 0) {
74        mLength = 0;
75    }
76    if (mLength > INT64_MAX - mOffset) {
77        mLength = INT64_MAX - mOffset;
78    }
79    struct stat s;
80    if (fstat(fd, &s) == 0) {
81        if (mOffset > s.st_size) {
82            mOffset = s.st_size;
83            mLength = 0;
84        }
85        if (mOffset + mLength > s.st_size) {
86            mLength = s.st_size - mOffset;
87        }
88    }
89    if (mOffset != offset || mLength != length) {
90        ALOGW("offset/length adjusted from %lld/%lld to %lld/%lld",
91                (long long) offset, (long long) length,
92                (long long) mOffset, (long long) mLength);
93    }
94
95    mName = String8::format(
96            "FileSource(fd(%s), %lld, %lld)",
97            nameForFd(fd).c_str(),
98            (long long) mOffset,
99            (long long) mLength);
100
101}
102
103FileSource::~FileSource() {
104    if (mFd >= 0) {
105        ::close(mFd);
106        mFd = -1;
107    }
108
109    if (mDrmBuf != NULL) {
110        delete[] mDrmBuf;
111        mDrmBuf = NULL;
112    }
113
114    if (mDecryptHandle != NULL) {
115        // To release mDecryptHandle
116        CHECK(mDrmManagerClient);
117        mDrmManagerClient->closeDecryptSession(mDecryptHandle);
118        mDecryptHandle = NULL;
119    }
120
121    if (mDrmManagerClient != NULL) {
122        delete mDrmManagerClient;
123        mDrmManagerClient = NULL;
124    }
125}
126
127status_t FileSource::initCheck() const {
128    return mFd >= 0 ? OK : NO_INIT;
129}
130
131ssize_t FileSource::readAt(off64_t offset, void *data, size_t size) {
132    if (mFd < 0) {
133        return NO_INIT;
134    }
135
136    Mutex::Autolock autoLock(mLock);
137
138    if (mLength >= 0) {
139        if (offset >= mLength) {
140            return 0;  // read beyond EOF.
141        }
142        uint64_t numAvailable = mLength - offset;
143        if ((uint64_t)size > numAvailable) {
144            size = numAvailable;
145        }
146    }
147
148    if (mDecryptHandle != NULL && DecryptApiType::CONTAINER_BASED
149            == mDecryptHandle->decryptApiType) {
150        return readAtDRM(offset, data, size);
151   } else {
152        off64_t result = lseek64(mFd, offset + mOffset, SEEK_SET);
153        if (result == -1) {
154            ALOGE("seek to %lld failed", (long long)(offset + mOffset));
155            return UNKNOWN_ERROR;
156        }
157
158        return ::read(mFd, data, size);
159    }
160}
161
162status_t FileSource::getSize(off64_t *size) {
163    Mutex::Autolock autoLock(mLock);
164
165    if (mFd < 0) {
166        return NO_INIT;
167    }
168
169    *size = mLength;
170
171    return OK;
172}
173
174sp<DecryptHandle> FileSource::DrmInitialization(const char *mime) {
175    if (getuid() == AID_MEDIA_EX) return nullptr; // no DRM in media extractor
176    if (mDrmManagerClient == NULL) {
177        mDrmManagerClient = new DrmManagerClient();
178    }
179
180    if (mDrmManagerClient == NULL) {
181        return NULL;
182    }
183
184    if (mDecryptHandle == NULL) {
185        mDecryptHandle = mDrmManagerClient->openDecryptSession(
186                mFd, mOffset, mLength, mime);
187    }
188
189    if (mDecryptHandle == NULL) {
190        delete mDrmManagerClient;
191        mDrmManagerClient = NULL;
192    }
193
194    return mDecryptHandle;
195}
196
197void FileSource::getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client) {
198    handle = mDecryptHandle;
199
200    *client = mDrmManagerClient;
201}
202
203ssize_t FileSource::readAtDRM(off64_t offset, void *data, size_t size) {
204    size_t DRM_CACHE_SIZE = 1024;
205    if (mDrmBuf == NULL) {
206        mDrmBuf = new unsigned char[DRM_CACHE_SIZE];
207    }
208
209    if (mDrmBuf != NULL && mDrmBufSize > 0 && (offset + mOffset) >= mDrmBufOffset
210            && (offset + mOffset + size) <= static_cast<size_t>(mDrmBufOffset + mDrmBufSize)) {
211        /* Use buffered data */
212        memcpy(data, (void*)(mDrmBuf+(offset+mOffset-mDrmBufOffset)), size);
213        return size;
214    } else if (size <= DRM_CACHE_SIZE) {
215        /* Buffer new data */
216        mDrmBufOffset =  offset + mOffset;
217        mDrmBufSize = mDrmManagerClient->pread(mDecryptHandle, mDrmBuf,
218                DRM_CACHE_SIZE, offset + mOffset);
219        if (mDrmBufSize > 0) {
220            int64_t dataRead = 0;
221            dataRead = size > static_cast<size_t>(mDrmBufSize) ? mDrmBufSize : size;
222            memcpy(data, (void*)mDrmBuf, dataRead);
223            return dataRead;
224        } else {
225            return mDrmBufSize;
226        }
227    } else {
228        /* Too big chunk to cache. Call DRM directly */
229        return mDrmManagerClient->pread(mDecryptHandle, data, size, offset + mOffset);
230    }
231}
232
233/* static */
234bool FileSource::requiresDrm(int fd, int64_t offset, int64_t length, const char *mime) {
235    std::unique_ptr<DrmManagerClient> drmClient(new DrmManagerClient());
236    sp<DecryptHandle> decryptHandle =
237            drmClient->openDecryptSession(fd, offset, length, mime);
238    bool requiresDrm = false;
239    if (decryptHandle != nullptr) {
240        requiresDrm = decryptHandle->decryptApiType == DecryptApiType::CONTAINER_BASED;
241        drmClient->closeDecryptSession(decryptHandle);
242    }
243    return requiresDrm;
244}
245
246}  // namespace android
247