diff --git a/libs/androidfw/StreamingZipInflater.cpp b/libs/androidfw/StreamingZipInflater.cpp
new file mode 100644
index 0000000..1dfec23
--- /dev/null
+++ b/libs/androidfw/StreamingZipInflater.cpp
@@ -0,0 +1,242 @@
+/*
+ * 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_NDEBUG 0
+#define LOG_TAG "szipinf"
+#include <utils/Log.h>
+
+#include <androidfw/StreamingZipInflater.h>
+#include <utils/FileMap.h>
+#include <string.h>
+#include <stddef.h>
+#include <assert.h>
+#include <unistd.h>
+#include <errno.h>
+
+/*
+ * TEMP_FAILURE_RETRY is defined by some, but not all, versions of
+ * <unistd.h>. (Alas, it is not as standard as we'd hoped!) So, if it's
+ * not already defined, then define it here.
+ */
+#ifndef TEMP_FAILURE_RETRY
+/* Used to retry syscalls that can return EINTR. */
+#define TEMP_FAILURE_RETRY(exp) ({         \
+    typeof (exp) _rc;                      \
+    do {                                   \
+        _rc = (exp);                       \
+    } while (_rc == -1 && errno == EINTR); \
+    _rc; })
+#endif
+
+static inline size_t min_of(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, off64_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() {
+    ALOGV("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_of(count, size_t(mOutTotalSize - mOutCurPosition));
+    while (toRead > 0) {
+        // First, write from whatever we already have decoded and ready to go
+        size_t deliverable = min_of(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) && (mDataMap == NULL)) {
+                int err = readNextChunk();
+                if (err < 0) {
+                    ALOGE("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;
+
+            /*
+            ALOGV("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) {
+                ALOGV("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
+                ALOGE("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_of(mInBufSize, mInTotalSize - mInNextChunkOffset);
+        if (toRead > 0) {
+            ssize_t didRead = TEMP_FAILURE_RETRY(::read(mFd, mInBuf, toRead));
+            //ALOGV("Reading input chunk, size %08x didread %08x", toRead, didRead);
+            if (didRead < 0) {
+                ALOGE("Error reading asset data: %s", strerror(errno));
+                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.
+off64_t StreamingZipInflater::seekAbsolute(off64_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;
+}