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-rw-r--r--libs/utils/Android.mk3
-rw-r--r--libs/utils/Asset.cpp74
-rw-r--r--libs/utils/StreamingZipInflater.cpp224
3 files changed, 271 insertions, 30 deletions
diff --git a/libs/utils/Android.mk b/libs/utils/Android.mk
index 8bd5823..2e20268 100644
--- a/libs/utils/Android.mk
+++ b/libs/utils/Android.mk
@@ -33,6 +33,7 @@ commonSources:= \
SharedBuffer.cpp \
Static.cpp \
StopWatch.cpp \
+ StreamingZipInflater.cpp \
String8.cpp \
String16.cpp \
StringArray.cpp \
@@ -131,4 +132,4 @@ endif
# team really wants is to build the stuff defined by this makefile.
ifeq (,$(ONE_SHOT_MAKEFILE))
include $(call first-makefiles-under,$(LOCAL_PATH))
-endif \ No newline at end of file
+endif
diff --git a/libs/utils/Asset.cpp b/libs/utils/Asset.cpp
index 4295123..cef7db4 100644
--- a/libs/utils/Asset.cpp
+++ b/libs/utils/Asset.cpp
@@ -24,6 +24,7 @@
#include <utils/Asset.h>
#include <utils/Atomic.h>
#include <utils/FileMap.h>
+#include <utils/StreamingZipInflater.h>
#include <utils/ZipUtils.h>
#include <utils/ZipFileRO.h>
#include <utils/Log.h>
@@ -659,7 +660,7 @@ const void* _FileAsset::ensureAlignment(FileMap* map)
*/
_CompressedAsset::_CompressedAsset(void)
: mStart(0), mCompressedLen(0), mUncompressedLen(0), mOffset(0),
- mMap(NULL), mFd(-1), mBuf(NULL)
+ mMap(NULL), mFd(-1), mZipInflater(NULL), mBuf(NULL)
{
}
@@ -698,6 +699,10 @@ status_t _CompressedAsset::openChunk(int fd, off_t offset,
mFd = fd;
assert(mBuf == NULL);
+ if (uncompressedLen > StreamingZipInflater::OUTPUT_CHUNK_SIZE) {
+ mZipInflater = new StreamingZipInflater(mFd, offset, uncompressedLen, compressedLen);
+ }
+
return NO_ERROR;
}
@@ -724,6 +729,9 @@ status_t _CompressedAsset::openChunk(FileMap* dataMap, int compressionMethod,
mUncompressedLen = uncompressedLen;
assert(mOffset == 0);
+ if (uncompressedLen > StreamingZipInflater::OUTPUT_CHUNK_SIZE) {
+ mZipInflater = new StreamingZipInflater(dataMap, uncompressedLen);
+ }
return NO_ERROR;
}
@@ -739,26 +747,29 @@ ssize_t _CompressedAsset::read(void* buf, size_t count)
assert(mOffset >= 0 && mOffset <= mUncompressedLen);
- // TODO: if mAccessMode == ACCESS_STREAMING, use zlib more cleverly
+ /* If we're relying on a streaming inflater, go through that */
+ if (mZipInflater) {
+ actual = mZipInflater->read(buf, count);
+ } else {
+ if (mBuf == NULL) {
+ if (getBuffer(false) == NULL)
+ return -1;
+ }
+ assert(mBuf != NULL);
- if (mBuf == NULL) {
- if (getBuffer(false) == NULL)
- return -1;
- }
- assert(mBuf != NULL);
+ /* adjust count if we're near EOF */
+ maxLen = mUncompressedLen - mOffset;
+ if (count > maxLen)
+ count = maxLen;
- /* adjust count if we're near EOF */
- maxLen = mUncompressedLen - mOffset;
- if (count > maxLen)
- count = maxLen;
+ if (!count)
+ return 0;
- if (!count)
- return 0;
-
- /* copy from buffer */
- //printf("comp buf read\n");
- memcpy(buf, (char*)mBuf + mOffset, count);
- actual = count;
+ /* copy from buffer */
+ //printf("comp buf read\n");
+ memcpy(buf, (char*)mBuf + mOffset, count);
+ actual = count;
+ }
mOffset += actual;
return actual;
@@ -780,6 +791,9 @@ off_t _CompressedAsset::seek(off_t offset, int whence)
if (newPosn == (off_t) -1)
return newPosn;
+ if (mZipInflater) {
+ mZipInflater->seekAbsolute(newPosn);
+ }
mOffset = newPosn;
return mOffset;
}
@@ -793,10 +807,12 @@ void _CompressedAsset::close(void)
mMap->release();
mMap = NULL;
}
- if (mBuf != NULL) {
- delete[] mBuf;
- mBuf = NULL;
- }
+
+ delete[] mBuf;
+ mBuf = NULL;
+
+ delete mZipInflater;
+ mZipInflater = NULL;
if (mFd > 0) {
::close(mFd);
@@ -817,12 +833,6 @@ const void* _CompressedAsset::getBuffer(bool wordAligned)
if (mBuf != NULL)
return mBuf;
- if (mUncompressedLen > UNCOMPRESS_DATA_MAX) {
- LOGD("Data exceeds UNCOMPRESS_DATA_MAX (%ld vs %d)\n",
- (long) mUncompressedLen, UNCOMPRESS_DATA_MAX);
- goto bail;
- }
-
/*
* Allocate a buffer and read the file into it.
*/
@@ -853,7 +863,13 @@ const void* _CompressedAsset::getBuffer(bool wordAligned)
goto bail;
}
- /* success! */
+ /*
+ * Success - now that we have the full asset in RAM we
+ * no longer need the streaming inflater
+ */
+ delete mZipInflater;
+ mZipInflater = NULL;
+
mBuf = buf;
buf = NULL;
diff --git a/libs/utils/StreamingZipInflater.cpp b/libs/utils/StreamingZipInflater.cpp
new file mode 100644
index 0000000..2ebec93
--- /dev/null
+++ b/libs/utils/StreamingZipInflater.cpp
@@ -0,0 +1,224 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "szipinf"
+#include <utils/Log.h>
+
+#include <utils/FileMap.h>
+#include <utils/StreamingZipInflater.h>
+#include <string.h>
+#include <assert.h>
+
+static inline size_t min(size_t a, size_t b) { return (a < b) ? a : b; }
+
+using namespace android;
+
+/*
+ * Streaming access to compressed asset data in an open fd
+ */
+StreamingZipInflater::StreamingZipInflater(int fd, off_t compDataStart,
+ size_t uncompSize, size_t compSize) {
+ mFd = fd;
+ mDataMap = NULL;
+ mInFileStart = compDataStart;
+ mOutTotalSize = uncompSize;
+ mInTotalSize = compSize;
+
+ mInBufSize = StreamingZipInflater::INPUT_CHUNK_SIZE;
+ mInBuf = new uint8_t[mInBufSize];
+
+ mOutBufSize = StreamingZipInflater::OUTPUT_CHUNK_SIZE;
+ mOutBuf = new uint8_t[mOutBufSize];
+
+ initInflateState();
+}
+
+/*
+ * Streaming access to compressed data held in an mmapped region of memory
+ */
+StreamingZipInflater::StreamingZipInflater(FileMap* dataMap, size_t uncompSize) {
+ mFd = -1;
+ mDataMap = dataMap;
+ mOutTotalSize = uncompSize;
+ mInTotalSize = dataMap->getDataLength();
+
+ mInBuf = (uint8_t*) dataMap->getDataPtr();
+ mInBufSize = mInTotalSize;
+
+ mOutBufSize = StreamingZipInflater::OUTPUT_CHUNK_SIZE;
+ mOutBuf = new uint8_t[mOutBufSize];
+
+ initInflateState();
+}
+
+StreamingZipInflater::~StreamingZipInflater() {
+ // tear down the in-flight zip state just in case
+ ::inflateEnd(&mInflateState);
+
+ if (mDataMap == NULL) {
+ delete [] mInBuf;
+ }
+ delete [] mOutBuf;
+}
+
+void StreamingZipInflater::initInflateState() {
+ LOGD("Initializing inflate state");
+
+ memset(&mInflateState, 0, sizeof(mInflateState));
+ mInflateState.zalloc = Z_NULL;
+ mInflateState.zfree = Z_NULL;
+ mInflateState.opaque = Z_NULL;
+ mInflateState.next_in = (Bytef*)mInBuf;
+ mInflateState.next_out = (Bytef*) mOutBuf;
+ mInflateState.avail_out = mOutBufSize;
+ mInflateState.data_type = Z_UNKNOWN;
+
+ mOutLastDecoded = mOutDeliverable = mOutCurPosition = 0;
+ mInNextChunkOffset = 0;
+ mStreamNeedsInit = true;
+
+ if (mDataMap == NULL) {
+ ::lseek(mFd, mInFileStart, SEEK_SET);
+ mInflateState.avail_in = 0; // set when a chunk is read in
+ } else {
+ mInflateState.avail_in = mInBufSize;
+ }
+}
+
+/*
+ * Basic approach:
+ *
+ * 1. If we have undelivered uncompressed data, send it. At this point
+ * either we've satisfied the request, or we've exhausted the available
+ * output data in mOutBuf.
+ *
+ * 2. While we haven't sent enough data to satisfy the request:
+ * 0. if the request is for more data than exists, bail.
+ * a. if there is no input data to decode, read some into the input buffer
+ * and readjust the z_stream input pointers
+ * b. point the output to the start of the output buffer and decode what we can
+ * c. deliver whatever output data we can
+ */
+ssize_t StreamingZipInflater::read(void* outBuf, size_t count) {
+ uint8_t* dest = (uint8_t*) outBuf;
+ size_t bytesRead = 0;
+ size_t toRead = min(count, size_t(mOutTotalSize - mOutCurPosition));
+ while (toRead > 0) {
+ // First, write from whatever we already have decoded and ready to go
+ size_t deliverable = min(toRead, mOutLastDecoded - mOutDeliverable);
+ if (deliverable > 0) {
+ if (outBuf != NULL) memcpy(dest, mOutBuf + mOutDeliverable, deliverable);
+ mOutDeliverable += deliverable;
+ mOutCurPosition += deliverable;
+ dest += deliverable;
+ bytesRead += deliverable;
+ toRead -= deliverable;
+ }
+
+ // need more data? time to decode some.
+ if (toRead > 0) {
+ // if we don't have any data to decode, read some in. If we're working
+ // from mmapped data this won't happen, because the clipping to total size
+ // will prevent reading off the end of the mapped input chunk.
+ if (mInflateState.avail_in == 0) {
+ int err = readNextChunk();
+ if (err < 0) {
+ LOGE("Unable to access asset data: %d", err);
+ if (!mStreamNeedsInit) {
+ ::inflateEnd(&mInflateState);
+ initInflateState();
+ }
+ return -1;
+ }
+ }
+ // we know we've drained whatever is in the out buffer now, so just
+ // start from scratch there, reading all the input we have at present.
+ mInflateState.next_out = (Bytef*) mOutBuf;
+ mInflateState.avail_out = mOutBufSize;
+
+ /*
+ LOGD("Inflating to outbuf: avail_in=%u avail_out=%u next_in=%p next_out=%p",
+ mInflateState.avail_in, mInflateState.avail_out,
+ mInflateState.next_in, mInflateState.next_out);
+ */
+ int result = Z_OK;
+ if (mStreamNeedsInit) {
+ LOGI("Initializing zlib to inflate");
+ result = inflateInit2(&mInflateState, -MAX_WBITS);
+ mStreamNeedsInit = false;
+ }
+ if (result == Z_OK) result = ::inflate(&mInflateState, Z_SYNC_FLUSH);
+ if (result < 0) {
+ // Whoops, inflation failed
+ LOGE("Error inflating asset: %d", result);
+ ::inflateEnd(&mInflateState);
+ initInflateState();
+ return -1;
+ } else {
+ if (result == Z_STREAM_END) {
+ // we know we have to have reached the target size here and will
+ // not try to read any further, so just wind things up.
+ ::inflateEnd(&mInflateState);
+ }
+
+ // Note how much data we got, and off we go
+ mOutDeliverable = 0;
+ mOutLastDecoded = mOutBufSize - mInflateState.avail_out;
+ }
+ }
+ }
+ return bytesRead;
+}
+
+int StreamingZipInflater::readNextChunk() {
+ assert(mDataMap == NULL);
+
+ if (mInNextChunkOffset < mInTotalSize) {
+ size_t toRead = min(mInBufSize, mInTotalSize - mInNextChunkOffset);
+ if (toRead > 0) {
+ ssize_t didRead = ::read(mFd, mInBuf, toRead);
+ //LOGD("Reading input chunk, size %08x didread %08x", toRead, didRead);
+ if (didRead < 0) {
+ // TODO: error
+ LOGE("Error reading asset data");
+ return didRead;
+ } else {
+ mInNextChunkOffset += didRead;
+ mInflateState.next_in = (Bytef*) mInBuf;
+ mInflateState.avail_in = didRead;
+ }
+ }
+ }
+ return 0;
+}
+
+// seeking backwards requires uncompressing fom the beginning, so is very
+// expensive. seeking forwards only requires uncompressing from the current
+// position to the destination.
+off_t StreamingZipInflater::seekAbsolute(off_t absoluteInputPosition) {
+ if (absoluteInputPosition < mOutCurPosition) {
+ // rewind and reprocess the data from the beginning
+ if (!mStreamNeedsInit) {
+ ::inflateEnd(&mInflateState);
+ }
+ initInflateState();
+ read(NULL, absoluteInputPosition);
+ } else if (absoluteInputPosition > mOutCurPosition) {
+ read(NULL, absoluteInputPosition - mOutCurPosition);
+ }
+ // else if the target position *is* our current position, do nothing
+ return absoluteInputPosition;
+}
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