diff --git a/tools/zipalign/ZipAlign.cpp b/tools/zipalign/ZipAlign.cpp
new file mode 100644
index 0000000..9e3cb66
--- /dev/null
+++ b/tools/zipalign/ZipAlign.cpp
@@ -0,0 +1,253 @@
+/*
+ * Copyright (C) 2008 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.
+ */
+/*
+ * Zip alignment tool
+ */
+#include "utils/ZipFile.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+using namespace android;
+
+/*
+ * Show program usage.
+ */
+void usage(void)
+{
+    fprintf(stderr, "Zip alignment utility\n");
+    fprintf(stderr,
+        "Usage: zipalign [-f] [-v] <align> infile.zip outfile.zip\n");
+}
+
+/*
+ * Copy all entries from "pZin" to "pZout", aligning as needed.
+ */
+static int copyAndAlign(ZipFile* pZin, ZipFile* pZout, int alignment)
+{
+    int numEntries = pZin->getNumEntries();
+    ZipEntry* pEntry;
+    int bias = 0;
+    status_t status;
+
+    for (int i = 0; i < numEntries; i++) {
+        ZipEntry* pNewEntry;
+        int padding = 0;
+
+        pEntry = pZin->getEntryByIndex(i);
+        if (pEntry == NULL) {
+            fprintf(stderr, "ERROR: unable to retrieve entry %d\n", i);
+            return 1;
+        }
+
+        if (pEntry->isCompressed()) {
+            /* copy the entry without padding */
+            //printf("--- %s: orig at %ld len=%ld (compressed)\n",
+            //    pEntry->getFileName(), (long) pEntry->getFileOffset(),
+            //    (long) pEntry->getUncompressedLen());
+
+        } else {
+            /*
+             * Copy the entry, adjusting as required.  We assume that the
+             * file position in the new file will be equal to the file
+             * position in the original.
+             */
+            long newOffset = pEntry->getFileOffset() + bias;
+            padding = (alignment - (newOffset % alignment)) % alignment;
+
+            //printf("--- %s: orig at %ld(+%d) len=%ld, adding pad=%d\n",
+            //    pEntry->getFileName(), (long) pEntry->getFileOffset(),
+            //    bias, (long) pEntry->getUncompressedLen(), padding);
+        }
+
+        status = pZout->add(pZin, pEntry, padding, &pNewEntry);
+        if (status != NO_ERROR)
+            return 1;
+        bias += padding;
+        //printf(" added '%s' at %ld (pad=%d)\n",
+        //    pNewEntry->getFileName(), (long) pNewEntry->getFileOffset(),
+        //    padding);
+    }
+
+    return 0;
+}
+
+/*
+ * Process a file.  We open the input and output files, failing if the
+ * output file exists and "force" wasn't specified.
+ */
+static int process(const char* inFileName, const char* outFileName,
+    int alignment, bool force)
+{
+    ZipFile zin, zout;
+
+    //printf("PROCESS: align=%d in='%s' out='%s' force=%d\n",
+    //    alignment, inFileName, outFileName, force);
+
+    /* this mode isn't supported -- do a trivial check */
+    if (strcmp(inFileName, outFileName) == 0) {
+        fprintf(stderr, "Input and output can't be same file\n");
+        return 1;
+    }
+
+    /* don't overwrite existing unless given permission */
+    if (!force && access(outFileName, F_OK) == 0) {
+        fprintf(stderr, "Output file '%s' exists\n", outFileName);
+        return 1;
+    }
+
+    if (zin.open(inFileName, ZipFile::kOpenReadOnly) != NO_ERROR) {
+        fprintf(stderr, "Unable to open '%s' as zip archive\n", inFileName);
+        return 1;
+    }
+    if (zout.open(outFileName,
+            ZipFile::kOpenReadWrite|ZipFile::kOpenCreate|ZipFile::kOpenTruncate)
+        != NO_ERROR)
+    {
+        fprintf(stderr, "Unable to open '%s' as zip archive\n", inFileName);
+        return 1;
+    }
+
+    int result = copyAndAlign(&zin, &zout, alignment);
+    if (result != 0) {
+        printf("zipalign: failed rewriting '%s' to '%s'\n",
+            inFileName, outFileName);
+    }
+    return result;
+}
+
+/*
+ * Verify the alignment of a zip archive.
+ */
+static int verify(const char* fileName, int alignment, bool verbose)
+{
+    ZipFile zipFile;
+    bool foundBad = false;
+
+    if (verbose)
+        printf("Verifying alignment of %s (%d)...\n", fileName, alignment);
+
+    if (zipFile.open(fileName, ZipFile::kOpenReadOnly) != NO_ERROR) {
+        fprintf(stderr, "Unable to open '%s' for verification\n", fileName);
+        return 1;
+    }
+
+    int numEntries = zipFile.getNumEntries();
+    ZipEntry* pEntry;
+
+    for (int i = 0; i < numEntries; i++) {
+        pEntry = zipFile.getEntryByIndex(i);
+        if (pEntry->isCompressed()) {
+            if (verbose) {
+                printf("%8ld %s (OK - compressed)\n", 
+                    (long) pEntry->getFileOffset(), pEntry->getFileName());
+            }
+        } else {
+            long offset = pEntry->getFileOffset();
+            if ((offset % alignment) != 0) {
+                if (verbose) {
+                    printf("%8ld %s (BAD - %ld)\n", 
+                        (long) offset, pEntry->getFileName(),
+                        offset % alignment);
+                }
+                foundBad = true;
+            } else {
+                if (verbose) {
+                    printf("%8ld %s (OK)\n",
+                        (long) offset, pEntry->getFileName());
+                }
+            }
+        }
+    }
+
+    if (verbose)
+        printf("Verification %s\n", foundBad ? "FAILED" : "succesful");
+
+    return foundBad ? 1 : 0;
+}
+
+/*
+ * Parse args.
+ */
+int main(int argc, char* const argv[])
+{
+    bool wantUsage = false;
+    bool force = false;
+    bool verbose = false;
+    int result = 1;
+    int alignment;
+    char* endp;
+
+    if (argc < 4) {
+        wantUsage = true;
+        goto bail;
+    }
+
+    argc--;
+    argv++;
+
+    while (argc && argv[0][0] == '-') {
+        const char* cp = argv[0] +1;
+
+        while (*cp != '\0') {
+            switch (*cp) {
+            case 'f':
+                force = true;
+                break;
+            case 'v':
+                verbose = true;
+                break;
+            default:
+                fprintf(stderr, "ERROR: unknown flag -%c\n", *cp);
+                wantUsage = true;
+                goto bail;
+            }
+
+            cp++;
+        }
+
+        argc--;
+        argv++;
+    }
+
+    if (argc != 3) {
+        wantUsage = true;
+        goto bail;
+    }
+
+    alignment = strtol(argv[0], &endp, 10);
+    if (*endp != '\0' || alignment <= 0) {
+        fprintf(stderr, "Invalid value for alignment: %s\n", argv[0]);
+        wantUsage = true;
+        goto bail;
+    }
+
+    /* create the new archive */
+    result = process(argv[1], argv[2], alignment, force);
+
+    /* trust, but verify */
+    if (result == 0)
+        result = verify(argv[2], alignment, verbose);
+
+bail:
+    if (wantUsage) {
+        usage();
+        result = 2;
+    }
+
+    return result;
+}
+