ZipAlign.cpp revision 3f2933b2091e388a4d5e9c09b0d69ffe691cf674 
1/*
2 * Copyright (C) 2008 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 * Zip alignment tool
18 */
19#include "utils/ZipFile.h"
20
21#include <stdlib.h>
22#include <stdio.h>
23
24using namespace android;
25
26/*
27 * Show program usage.
28 */
29void usage(void)
30{
31    fprintf(stderr, "Zip alignment utility\n");
32    fprintf(stderr,
33        "Usage: zipalign [-f] [-v] <align> infile.zip outfile.zip\n"
34        "       zipalign -c [-v] <align> infile.zip\n" );
35}
36
37/*
38 * Copy all entries from "pZin" to "pZout", aligning as needed.
39 */
40static int copyAndAlign(ZipFile* pZin, ZipFile* pZout, int alignment)
41{
42    int numEntries = pZin->getNumEntries();
43    ZipEntry* pEntry;
44    int bias = 0;
45    status_t status;
46
47    for (int i = 0; i < numEntries; i++) {
48        ZipEntry* pNewEntry;
49        int padding = 0;
50
51        pEntry = pZin->getEntryByIndex(i);
52        if (pEntry == NULL) {
53            fprintf(stderr, "ERROR: unable to retrieve entry %d\n", i);
54            return 1;
55        }
56
57        if (pEntry->isCompressed()) {
58            /* copy the entry without padding */
59            //printf("--- %s: orig at %ld len=%ld (compressed)\n",
60            //    pEntry->getFileName(), (long) pEntry->getFileOffset(),
61            //    (long) pEntry->getUncompressedLen());
62
63        } else {
64            /*
65             * Copy the entry, adjusting as required.  We assume that the
66             * file position in the new file will be equal to the file
67             * position in the original.
68             */
69            long newOffset = pEntry->getFileOffset() + bias;
70            padding = (alignment - (newOffset % alignment)) % alignment;
71
72            //printf("--- %s: orig at %ld(+%d) len=%ld, adding pad=%d\n",
73            //    pEntry->getFileName(), (long) pEntry->getFileOffset(),
74            //    bias, (long) pEntry->getUncompressedLen(), padding);
75        }
76
77        status = pZout->add(pZin, pEntry, padding, &pNewEntry);
78        if (status != NO_ERROR)
79            return 1;
80        bias += padding;
81        //printf(" added '%s' at %ld (pad=%d)\n",
82        //    pNewEntry->getFileName(), (long) pNewEntry->getFileOffset(),
83        //    padding);
84    }
85
86    return 0;
87}
88
89/*
90 * Process a file.  We open the input and output files, failing if the
91 * output file exists and "force" wasn't specified.
92 */
93static int process(const char* inFileName, const char* outFileName,
94    int alignment, bool force)
95{
96    ZipFile zin, zout;
97
98    //printf("PROCESS: align=%d in='%s' out='%s' force=%d\n",
99    //    alignment, inFileName, outFileName, force);
100
101    /* this mode isn't supported -- do a trivial check */
102    if (strcmp(inFileName, outFileName) == 0) {
103        fprintf(stderr, "Input and output can't be same file\n");
104        return 1;
105    }
106
107    /* don't overwrite existing unless given permission */
108    if (!force && access(outFileName, F_OK) == 0) {
109        fprintf(stderr, "Output file '%s' exists\n", outFileName);
110        return 1;
111    }
112
113    if (zin.open(inFileName, ZipFile::kOpenReadOnly) != NO_ERROR) {
114        fprintf(stderr, "Unable to open '%s' as zip archive\n", inFileName);
115        return 1;
116    }
117    if (zout.open(outFileName,
118            ZipFile::kOpenReadWrite|ZipFile::kOpenCreate|ZipFile::kOpenTruncate)
119        != NO_ERROR)
120    {
121        fprintf(stderr, "Unable to open '%s' as zip archive\n", inFileName);
122        return 1;
123    }
124
125    int result = copyAndAlign(&zin, &zout, alignment);
126    if (result != 0) {
127        printf("zipalign: failed rewriting '%s' to '%s'\n",
128            inFileName, outFileName);
129    }
130    return result;
131}
132
133/*
134 * Verify the alignment of a zip archive.
135 */
136static int verify(const char* fileName, int alignment, bool verbose)
137{
138    ZipFile zipFile;
139    bool foundBad = false;
140
141    if (verbose)
142        printf("Verifying alignment of %s (%d)...\n", fileName, alignment);
143
144    if (zipFile.open(fileName, ZipFile::kOpenReadOnly) != NO_ERROR) {
145        fprintf(stderr, "Unable to open '%s' for verification\n", fileName);
146        return 1;
147    }
148
149    int numEntries = zipFile.getNumEntries();
150    ZipEntry* pEntry;
151
152    for (int i = 0; i < numEntries; i++) {
153        pEntry = zipFile.getEntryByIndex(i);
154        if (pEntry->isCompressed()) {
155            if (verbose) {
156                printf("%8ld %s (OK - compressed)\n",
157                    (long) pEntry->getFileOffset(), pEntry->getFileName());
158            }
159        } else {
160            long offset = pEntry->getFileOffset();
161            if ((offset % alignment) != 0) {
162                if (verbose) {
163                    printf("%8ld %s (BAD - %ld)\n",
164                        (long) offset, pEntry->getFileName(),
165                        offset % alignment);
166                }
167                foundBad = true;
168            } else {
169                if (verbose) {
170                    printf("%8ld %s (OK)\n",
171                        (long) offset, pEntry->getFileName());
172                }
173            }
174        }
175    }
176
177    if (verbose)
178        printf("Verification %s\n", foundBad ? "FAILED" : "succesful");
179
180    return foundBad ? 1 : 0;
181}
182
183/*
184 * Parse args.
185 */
186int main(int argc, char* const argv[])
187{
188    bool wantUsage = false;
189    bool check = false;
190    bool force = false;
191    bool verbose = false;
192    int result = 1;
193    int alignment;
194    char* endp;
195
196    if (argc < 4) {
197        wantUsage = true;
198        goto bail;
199    }
200
201    argc--;
202    argv++;
203
204    while (argc && argv[0][0] == '-') {
205        const char* cp = argv[0] +1;
206
207        while (*cp != '\0') {
208            switch (*cp) {
209            case 'c':
210                check = true;
211                break;
212            case 'f':
213                force = true;
214                break;
215            case 'v':
216                verbose = true;
217                break;
218            default:
219                fprintf(stderr, "ERROR: unknown flag -%c\n", *cp);
220                wantUsage = true;
221                goto bail;
222            }
223
224            cp++;
225        }
226
227        argc--;
228        argv++;
229    }
230
231    if (!((check && argc == 2) || (!check && argc == 3))) {
232        wantUsage = true;
233        goto bail;
234    }
235
236    alignment = strtol(argv[0], &endp, 10);
237    if (*endp != '\0' || alignment <= 0) {
238        fprintf(stderr, "Invalid value for alignment: %s\n", argv[0]);
239        wantUsage = true;
240        goto bail;
241    }
242
243    if (check) {
244        /* check existing archive for correct alignment */
245        result = verify(argv[1], alignment, verbose);
246    } else {
247        /* create the new archive */
248        result = process(argv[1], argv[2], alignment, force);
249
250        /* trust, but verify */
251        if (result == 0)
252            result = verify(argv[2], alignment, verbose);
253    }
254
255bail:
256    if (wantUsage) {
257        usage();
258        result = 2;
259    }
260
261    return result;
262}
263