Merge branch 'cc/trailers-corner-case-fix'
[git] / archive-zip.c
1 /*
2  * Copyright (c) 2006 Rene Scharfe
3  */
4 #include "cache.h"
5 #include "archive.h"
6 #include "streaming.h"
7 #include "utf8.h"
8 #include "userdiff.h"
9 #include "xdiff-interface.h"
10
11 static int zip_date;
12 static int zip_time;
13
14 static unsigned char *zip_dir;
15 static unsigned int zip_dir_size;
16
17 static unsigned int zip_offset;
18 static unsigned int zip_dir_offset;
19 static uint64_t zip_dir_entries;
20
21 static unsigned int max_creator_version;
22
23 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
24 #define ZIP_STREAM      (1 <<  3)
25 #define ZIP_UTF8        (1 << 11)
26
27 struct zip_local_header {
28         unsigned char magic[4];
29         unsigned char version[2];
30         unsigned char flags[2];
31         unsigned char compression_method[2];
32         unsigned char mtime[2];
33         unsigned char mdate[2];
34         unsigned char crc32[4];
35         unsigned char compressed_size[4];
36         unsigned char size[4];
37         unsigned char filename_length[2];
38         unsigned char extra_length[2];
39         unsigned char _end[1];
40 };
41
42 struct zip_data_desc {
43         unsigned char magic[4];
44         unsigned char crc32[4];
45         unsigned char compressed_size[4];
46         unsigned char size[4];
47         unsigned char _end[1];
48 };
49
50 struct zip_dir_header {
51         unsigned char magic[4];
52         unsigned char creator_version[2];
53         unsigned char version[2];
54         unsigned char flags[2];
55         unsigned char compression_method[2];
56         unsigned char mtime[2];
57         unsigned char mdate[2];
58         unsigned char crc32[4];
59         unsigned char compressed_size[4];
60         unsigned char size[4];
61         unsigned char filename_length[2];
62         unsigned char extra_length[2];
63         unsigned char comment_length[2];
64         unsigned char disk[2];
65         unsigned char attr1[2];
66         unsigned char attr2[4];
67         unsigned char offset[4];
68         unsigned char _end[1];
69 };
70
71 struct zip_dir_trailer {
72         unsigned char magic[4];
73         unsigned char disk[2];
74         unsigned char directory_start_disk[2];
75         unsigned char entries_on_this_disk[2];
76         unsigned char entries[2];
77         unsigned char size[4];
78         unsigned char offset[4];
79         unsigned char comment_length[2];
80         unsigned char _end[1];
81 };
82
83 struct zip_extra_mtime {
84         unsigned char magic[2];
85         unsigned char extra_size[2];
86         unsigned char flags[1];
87         unsigned char mtime[4];
88         unsigned char _end[1];
89 };
90
91 struct zip64_dir_trailer {
92         unsigned char magic[4];
93         unsigned char record_size[8];
94         unsigned char creator_version[2];
95         unsigned char version[2];
96         unsigned char disk[4];
97         unsigned char directory_start_disk[4];
98         unsigned char entries_on_this_disk[8];
99         unsigned char entries[8];
100         unsigned char size[8];
101         unsigned char offset[8];
102         unsigned char _end[1];
103 };
104
105 struct zip64_dir_trailer_locator {
106         unsigned char magic[4];
107         unsigned char disk[4];
108         unsigned char offset[8];
109         unsigned char number_of_disks[4];
110         unsigned char _end[1];
111 };
112
113 /*
114  * On ARM, padding is added at the end of the struct, so a simple
115  * sizeof(struct ...) reports two bytes more than the payload size
116  * we're interested in.
117  */
118 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
119 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
120 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
121 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
122 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
123 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
124         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
125 #define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
126 #define ZIP64_DIR_TRAILER_RECORD_SIZE \
127         (ZIP64_DIR_TRAILER_SIZE - \
128          offsetof(struct zip64_dir_trailer, creator_version))
129 #define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
130         offsetof(struct zip64_dir_trailer_locator, _end)
131
132 static void copy_le16(unsigned char *dest, unsigned int n)
133 {
134         dest[0] = 0xff & n;
135         dest[1] = 0xff & (n >> 010);
136 }
137
138 static void copy_le32(unsigned char *dest, unsigned int n)
139 {
140         dest[0] = 0xff & n;
141         dest[1] = 0xff & (n >> 010);
142         dest[2] = 0xff & (n >> 020);
143         dest[3] = 0xff & (n >> 030);
144 }
145
146 static void copy_le64(unsigned char *dest, uint64_t n)
147 {
148         dest[0] = 0xff & n;
149         dest[1] = 0xff & (n >> 010);
150         dest[2] = 0xff & (n >> 020);
151         dest[3] = 0xff & (n >> 030);
152         dest[4] = 0xff & (n >> 040);
153         dest[5] = 0xff & (n >> 050);
154         dest[6] = 0xff & (n >> 060);
155         dest[7] = 0xff & (n >> 070);
156 }
157
158 static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
159 {
160         if (n <= max)
161                 return n;
162         *clamped = 1;
163         return max;
164 }
165
166 static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
167 {
168         copy_le16(dest, clamp_max(n, 0xffff, clamped));
169 }
170
171 static void *zlib_deflate_raw(void *data, unsigned long size,
172                               int compression_level,
173                               unsigned long *compressed_size)
174 {
175         git_zstream stream;
176         unsigned long maxsize;
177         void *buffer;
178         int result;
179
180         git_deflate_init_raw(&stream, compression_level);
181         maxsize = git_deflate_bound(&stream, size);
182         buffer = xmalloc(maxsize);
183
184         stream.next_in = data;
185         stream.avail_in = size;
186         stream.next_out = buffer;
187         stream.avail_out = maxsize;
188
189         do {
190                 result = git_deflate(&stream, Z_FINISH);
191         } while (result == Z_OK);
192
193         if (result != Z_STREAM_END) {
194                 free(buffer);
195                 return NULL;
196         }
197
198         git_deflate_end(&stream);
199         *compressed_size = stream.total_out;
200
201         return buffer;
202 }
203
204 static void write_zip_data_desc(unsigned long size,
205                                 unsigned long compressed_size,
206                                 unsigned long crc)
207 {
208         struct zip_data_desc trailer;
209
210         copy_le32(trailer.magic, 0x08074b50);
211         copy_le32(trailer.crc32, crc);
212         copy_le32(trailer.compressed_size, compressed_size);
213         copy_le32(trailer.size, size);
214         write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
215 }
216
217 static void set_zip_dir_data_desc(struct zip_dir_header *header,
218                                   unsigned long size,
219                                   unsigned long compressed_size,
220                                   unsigned long crc)
221 {
222         copy_le32(header->crc32, crc);
223         copy_le32(header->compressed_size, compressed_size);
224         copy_le32(header->size, size);
225 }
226
227 static void set_zip_header_data_desc(struct zip_local_header *header,
228                                      unsigned long size,
229                                      unsigned long compressed_size,
230                                      unsigned long crc)
231 {
232         copy_le32(header->crc32, crc);
233         copy_le32(header->compressed_size, compressed_size);
234         copy_le32(header->size, size);
235 }
236
237 static int has_only_ascii(const char *s)
238 {
239         for (;;) {
240                 int c = *s++;
241                 if (c == '\0')
242                         return 1;
243                 if (!isascii(c))
244                         return 0;
245         }
246 }
247
248 static int entry_is_binary(const char *path, const void *buffer, size_t size)
249 {
250         struct userdiff_driver *driver = userdiff_find_by_path(path);
251         if (!driver)
252                 driver = userdiff_find_by_name("default");
253         if (driver->binary != -1)
254                 return driver->binary;
255         return buffer_is_binary(buffer, size);
256 }
257
258 #define STREAM_BUFFER_SIZE (1024 * 16)
259
260 static int write_zip_entry(struct archiver_args *args,
261                            const unsigned char *sha1,
262                            const char *path, size_t pathlen,
263                            unsigned int mode)
264 {
265         struct zip_local_header header;
266         struct zip_dir_header dirent;
267         struct zip_extra_mtime extra;
268         unsigned long attr2;
269         unsigned long compressed_size;
270         unsigned long crc;
271         unsigned long direntsize;
272         int method;
273         unsigned char *out;
274         void *deflated = NULL;
275         void *buffer;
276         struct git_istream *stream = NULL;
277         unsigned long flags = 0;
278         unsigned long size;
279         int is_binary = -1;
280         const char *path_without_prefix = path + args->baselen;
281         unsigned int creator_version = 0;
282
283         crc = crc32(0, NULL, 0);
284
285         if (!has_only_ascii(path)) {
286                 if (is_utf8(path))
287                         flags |= ZIP_UTF8;
288                 else
289                         warning("Path is not valid UTF-8: %s", path);
290         }
291
292         if (pathlen > 0xffff) {
293                 return error("path too long (%d chars, SHA1: %s): %s",
294                                 (int)pathlen, sha1_to_hex(sha1), path);
295         }
296
297         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
298                 method = 0;
299                 attr2 = 16;
300                 out = NULL;
301                 size = 0;
302                 compressed_size = 0;
303                 buffer = NULL;
304         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
305                 enum object_type type = sha1_object_info(sha1, &size);
306
307                 method = 0;
308                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
309                         (mode & 0111) ? ((mode) << 16) : 0;
310                 if (S_ISLNK(mode) || (mode & 0111))
311                         creator_version = 0x0317;
312                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
313                         method = 8;
314
315                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
316                     size > big_file_threshold) {
317                         stream = open_istream(sha1, &type, &size, NULL);
318                         if (!stream)
319                                 return error("cannot stream blob %s",
320                                              sha1_to_hex(sha1));
321                         flags |= ZIP_STREAM;
322                         out = buffer = NULL;
323                 } else {
324                         buffer = sha1_file_to_archive(args, path, sha1, mode,
325                                                       &type, &size);
326                         if (!buffer)
327                                 return error("cannot read %s",
328                                              sha1_to_hex(sha1));
329                         crc = crc32(crc, buffer, size);
330                         is_binary = entry_is_binary(path_without_prefix,
331                                                     buffer, size);
332                         out = buffer;
333                 }
334                 compressed_size = (method == 0) ? size : 0;
335         } else {
336                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
337                                 sha1_to_hex(sha1));
338         }
339
340         if (creator_version > max_creator_version)
341                 max_creator_version = creator_version;
342
343         if (buffer && method == 8) {
344                 out = deflated = zlib_deflate_raw(buffer, size,
345                                                   args->compression_level,
346                                                   &compressed_size);
347                 if (!out || compressed_size >= size) {
348                         out = buffer;
349                         method = 0;
350                         compressed_size = size;
351                 }
352         }
353
354         copy_le16(extra.magic, 0x5455);
355         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
356         extra.flags[0] = 1;     /* just mtime */
357         copy_le32(extra.mtime, args->time);
358
359         /* make sure we have enough free space in the dictionary */
360         direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
361         while (zip_dir_size < zip_dir_offset + direntsize) {
362                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
363                 zip_dir = xrealloc(zip_dir, zip_dir_size);
364         }
365
366         copy_le32(dirent.magic, 0x02014b50);
367         copy_le16(dirent.creator_version, creator_version);
368         copy_le16(dirent.version, 10);
369         copy_le16(dirent.flags, flags);
370         copy_le16(dirent.compression_method, method);
371         copy_le16(dirent.mtime, zip_time);
372         copy_le16(dirent.mdate, zip_date);
373         set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
374         copy_le16(dirent.filename_length, pathlen);
375         copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
376         copy_le16(dirent.comment_length, 0);
377         copy_le16(dirent.disk, 0);
378         copy_le32(dirent.attr2, attr2);
379         copy_le32(dirent.offset, zip_offset);
380
381         copy_le32(header.magic, 0x04034b50);
382         copy_le16(header.version, 10);
383         copy_le16(header.flags, flags);
384         copy_le16(header.compression_method, method);
385         copy_le16(header.mtime, zip_time);
386         copy_le16(header.mdate, zip_date);
387         set_zip_header_data_desc(&header, size, compressed_size, crc);
388         copy_le16(header.filename_length, pathlen);
389         copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
390         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
391         zip_offset += ZIP_LOCAL_HEADER_SIZE;
392         write_or_die(1, path, pathlen);
393         zip_offset += pathlen;
394         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
395         zip_offset += ZIP_EXTRA_MTIME_SIZE;
396         if (stream && method == 0) {
397                 unsigned char buf[STREAM_BUFFER_SIZE];
398                 ssize_t readlen;
399
400                 for (;;) {
401                         readlen = read_istream(stream, buf, sizeof(buf));
402                         if (readlen <= 0)
403                                 break;
404                         crc = crc32(crc, buf, readlen);
405                         if (is_binary == -1)
406                                 is_binary = entry_is_binary(path_without_prefix,
407                                                             buf, readlen);
408                         write_or_die(1, buf, readlen);
409                 }
410                 close_istream(stream);
411                 if (readlen)
412                         return readlen;
413
414                 compressed_size = size;
415                 zip_offset += compressed_size;
416
417                 write_zip_data_desc(size, compressed_size, crc);
418                 zip_offset += ZIP_DATA_DESC_SIZE;
419
420                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
421         } else if (stream && method == 8) {
422                 unsigned char buf[STREAM_BUFFER_SIZE];
423                 ssize_t readlen;
424                 git_zstream zstream;
425                 int result;
426                 size_t out_len;
427                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
428
429                 git_deflate_init_raw(&zstream, args->compression_level);
430
431                 compressed_size = 0;
432                 zstream.next_out = compressed;
433                 zstream.avail_out = sizeof(compressed);
434
435                 for (;;) {
436                         readlen = read_istream(stream, buf, sizeof(buf));
437                         if (readlen <= 0)
438                                 break;
439                         crc = crc32(crc, buf, readlen);
440                         if (is_binary == -1)
441                                 is_binary = entry_is_binary(path_without_prefix,
442                                                             buf, readlen);
443
444                         zstream.next_in = buf;
445                         zstream.avail_in = readlen;
446                         result = git_deflate(&zstream, 0);
447                         if (result != Z_OK)
448                                 die("deflate error (%d)", result);
449                         out_len = zstream.next_out - compressed;
450
451                         if (out_len > 0) {
452                                 write_or_die(1, compressed, out_len);
453                                 compressed_size += out_len;
454                                 zstream.next_out = compressed;
455                                 zstream.avail_out = sizeof(compressed);
456                         }
457
458                 }
459                 close_istream(stream);
460                 if (readlen)
461                         return readlen;
462
463                 zstream.next_in = buf;
464                 zstream.avail_in = 0;
465                 result = git_deflate(&zstream, Z_FINISH);
466                 if (result != Z_STREAM_END)
467                         die("deflate error (%d)", result);
468
469                 git_deflate_end(&zstream);
470                 out_len = zstream.next_out - compressed;
471                 write_or_die(1, compressed, out_len);
472                 compressed_size += out_len;
473                 zip_offset += compressed_size;
474
475                 write_zip_data_desc(size, compressed_size, crc);
476                 zip_offset += ZIP_DATA_DESC_SIZE;
477
478                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
479         } else if (compressed_size > 0) {
480                 write_or_die(1, out, compressed_size);
481                 zip_offset += compressed_size;
482         }
483
484         free(deflated);
485         free(buffer);
486
487         copy_le16(dirent.attr1, !is_binary);
488
489         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
490         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
491         memcpy(zip_dir + zip_dir_offset, path, pathlen);
492         zip_dir_offset += pathlen;
493         memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
494         zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
495         zip_dir_entries++;
496
497         return 0;
498 }
499
500 static void write_zip64_trailer(void)
501 {
502         struct zip64_dir_trailer trailer64;
503         struct zip64_dir_trailer_locator locator64;
504
505         copy_le32(trailer64.magic, 0x06064b50);
506         copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
507         copy_le16(trailer64.creator_version, max_creator_version);
508         copy_le16(trailer64.version, 45);
509         copy_le32(trailer64.disk, 0);
510         copy_le32(trailer64.directory_start_disk, 0);
511         copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
512         copy_le64(trailer64.entries, zip_dir_entries);
513         copy_le64(trailer64.size, zip_dir_offset);
514         copy_le64(trailer64.offset, zip_offset);
515
516         copy_le32(locator64.magic, 0x07064b50);
517         copy_le32(locator64.disk, 0);
518         copy_le64(locator64.offset, zip_offset + zip_dir_offset);
519         copy_le32(locator64.number_of_disks, 1);
520
521         write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
522         write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
523 }
524
525 static void write_zip_trailer(const unsigned char *sha1)
526 {
527         struct zip_dir_trailer trailer;
528         int clamped = 0;
529
530         copy_le32(trailer.magic, 0x06054b50);
531         copy_le16(trailer.disk, 0);
532         copy_le16(trailer.directory_start_disk, 0);
533         copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
534                         &clamped);
535         copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
536         copy_le32(trailer.size, zip_dir_offset);
537         copy_le32(trailer.offset, zip_offset);
538         copy_le16(trailer.comment_length, sha1 ? GIT_SHA1_HEXSZ : 0);
539
540         write_or_die(1, zip_dir, zip_dir_offset);
541         if (clamped)
542                 write_zip64_trailer();
543         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
544         if (sha1)
545                 write_or_die(1, sha1_to_hex(sha1), GIT_SHA1_HEXSZ);
546 }
547
548 static void dos_time(time_t *time, int *dos_date, int *dos_time)
549 {
550         struct tm *t = localtime(time);
551
552         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
553                     (t->tm_year + 1900 - 1980) * 512;
554         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
555 }
556
557 static int write_zip_archive(const struct archiver *ar,
558                              struct archiver_args *args)
559 {
560         int err;
561
562         dos_time(&args->time, &zip_date, &zip_time);
563
564         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
565         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
566
567         err = write_archive_entries(args, write_zip_entry);
568         if (!err)
569                 write_zip_trailer(args->commit_sha1);
570
571         free(zip_dir);
572
573         return err;
574 }
575
576 static struct archiver zip_archiver = {
577         "zip",
578         write_zip_archive,
579         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
580 };
581
582 void init_zip_archiver(void)
583 {
584         register_archiver(&zip_archiver);
585 }