archive-zip.c

   1 /*
   2  * Copyright (c) 2006 Rene Scharfe
   3  */
   4 #include "cache.h"
   5 #include "config.h"
   6 #include "archive.h"
   7 #include "streaming.h"
   8 #include "utf8.h"
   9 #include "object-store.h"
  10 #include "userdiff.h"
  11 #include "xdiff-interface.h"
  12 #include "date.h"
  13
  14 static int zip_date;
  15 static int zip_time;
  16
  17 /* We only care about the "buf" part here. */
  18 static struct strbuf zip_dir;
  19
  20 static uintmax_t zip_offset;
  21 static uint64_t zip_dir_entries;
  22
  23 static unsigned int max_creator_version;
  24
  25 #define ZIP_STREAM      (1 <<  3)
  26 #define ZIP_UTF8        (1 << 11)
  27
  28 enum zip_method {
  29         ZIP_METHOD_STORE = 0,
  30         ZIP_METHOD_DEFLATE = 8
  31 };
  32
  33 struct zip_local_header {
  34         unsigned char magic[4];
  35         unsigned char version[2];
  36         unsigned char flags[2];
  37         unsigned char compression_method[2];
  38         unsigned char mtime[2];
  39         unsigned char mdate[2];
  40         unsigned char crc32[4];
  41         unsigned char compressed_size[4];
  42         unsigned char size[4];
  43         unsigned char filename_length[2];
  44         unsigned char extra_length[2];
  45         unsigned char _end[1];
  46 };
  47
  48 struct zip_data_desc {
  49         unsigned char magic[4];
  50         unsigned char crc32[4];
  51         unsigned char compressed_size[4];
  52         unsigned char size[4];
  53         unsigned char _end[1];
  54 };
  55
  56 struct zip64_data_desc {
  57         unsigned char magic[4];
  58         unsigned char crc32[4];
  59         unsigned char compressed_size[8];
  60         unsigned char size[8];
  61         unsigned char _end[1];
  62 };
  63
  64 struct zip_dir_trailer {
  65         unsigned char magic[4];
  66         unsigned char disk[2];
  67         unsigned char directory_start_disk[2];
  68         unsigned char entries_on_this_disk[2];
  69         unsigned char entries[2];
  70         unsigned char size[4];
  71         unsigned char offset[4];
  72         unsigned char comment_length[2];
  73         unsigned char _end[1];
  74 };
  75
  76 struct zip_extra_mtime {
  77         unsigned char magic[2];
  78         unsigned char extra_size[2];
  79         unsigned char flags[1];
  80         unsigned char mtime[4];
  81         unsigned char _end[1];
  82 };
  83
  84 struct zip64_extra {
  85         unsigned char magic[2];
  86         unsigned char extra_size[2];
  87         unsigned char size[8];
  88         unsigned char compressed_size[8];
  89         unsigned char _end[1];
  90 };
  91
  92 struct zip64_dir_trailer {
  93         unsigned char magic[4];
  94         unsigned char record_size[8];
  95         unsigned char creator_version[2];
  96         unsigned char version[2];
  97         unsigned char disk[4];
  98         unsigned char directory_start_disk[4];
  99         unsigned char entries_on_this_disk[8];
 100         unsigned char entries[8];
 101         unsigned char size[8];
 102         unsigned char offset[8];
 103         unsigned char _end[1];
 104 };
 105
 106 struct zip64_dir_trailer_locator {
 107         unsigned char magic[4];
 108         unsigned char disk[4];
 109         unsigned char offset[8];
 110         unsigned char number_of_disks[4];
 111         unsigned char _end[1];
 112 };
 113
 114 /*
 115  * On ARM, padding is added at the end of the struct, so a simple
 116  * sizeof(struct ...) reports two bytes more than the payload size
 117  * we're interested in.
 118  */
 119 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
 120 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
 121 #define ZIP64_DATA_DESC_SIZE    offsetof(struct zip64_data_desc, _end)
 122 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
 123 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
 124 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
 125 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 126         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 127 #define ZIP64_EXTRA_SIZE        offsetof(struct zip64_extra, _end)
 128 #define ZIP64_EXTRA_PAYLOAD_SIZE \
 129         (ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
 130 #define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
 131 #define ZIP64_DIR_TRAILER_RECORD_SIZE \
 132         (ZIP64_DIR_TRAILER_SIZE - \
 133          offsetof(struct zip64_dir_trailer, creator_version))
 134 #define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
 135         offsetof(struct zip64_dir_trailer_locator, _end)
 136
 137 static void copy_le16(unsigned char *dest, unsigned int n)
 138 {
 139         dest[0] = 0xff & n;
 140         dest[1] = 0xff & (n >> 010);
 141 }
 142
 143 static void copy_le32(unsigned char *dest, unsigned int n)
 144 {
 145         dest[0] = 0xff & n;
 146         dest[1] = 0xff & (n >> 010);
 147         dest[2] = 0xff & (n >> 020);
 148         dest[3] = 0xff & (n >> 030);
 149 }
 150
 151 static void copy_le64(unsigned char *dest, uint64_t n)
 152 {
 153         dest[0] = 0xff & n;
 154         dest[1] = 0xff & (n >> 010);
 155         dest[2] = 0xff & (n >> 020);
 156         dest[3] = 0xff & (n >> 030);
 157         dest[4] = 0xff & (n >> 040);
 158         dest[5] = 0xff & (n >> 050);
 159         dest[6] = 0xff & (n >> 060);
 160         dest[7] = 0xff & (n >> 070);
 161 }
 162
 163 static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
 164 {
 165         if (n <= max)
 166                 return n;
 167         *clamped = 1;
 168         return max;
 169 }
 170
 171 static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
 172 {
 173         copy_le16(dest, clamp_max(n, 0xffff, clamped));
 174 }
 175
 176 static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
 177 {
 178         copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
 179 }
 180
 181 static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
 182 {
 183         while (size-- > 0) {
 184                 strbuf_addch(sb, n & 0xff);
 185                 n >>= 8;
 186         }
 187         return -!!n;
 188 }
 189
 190 static uint32_t clamp32(uintmax_t n)
 191 {
 192         const uintmax_t max = 0xffffffff;
 193         return (n < max) ? n : max;
 194 }
 195
 196 static void *zlib_deflate_raw(void *data, unsigned long size,
 197                               int compression_level,
 198                               unsigned long *compressed_size)
 199 {
 200         git_zstream stream;
 201         unsigned long maxsize;
 202         void *buffer;
 203         int result;
 204
 205         git_deflate_init_raw(&stream, compression_level);
 206         maxsize = git_deflate_bound(&stream, size);
 207         buffer = xmalloc(maxsize);
 208
 209         stream.next_in = data;
 210         stream.avail_in = size;
 211         stream.next_out = buffer;
 212         stream.avail_out = maxsize;
 213
 214         do {
 215                 result = git_deflate(&stream, Z_FINISH);
 216         } while (result == Z_OK);
 217
 218         if (result != Z_STREAM_END) {
 219                 free(buffer);
 220                 return NULL;
 221         }
 222
 223         git_deflate_end(&stream);
 224         *compressed_size = stream.total_out;
 225
 226         return buffer;
 227 }
 228
 229 static void write_zip_data_desc(unsigned long size,
 230                                 unsigned long compressed_size,
 231                                 unsigned long crc)
 232 {
 233         if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
 234                 struct zip64_data_desc trailer;
 235                 copy_le32(trailer.magic, 0x08074b50);
 236                 copy_le32(trailer.crc32, crc);
 237                 copy_le64(trailer.compressed_size, compressed_size);
 238                 copy_le64(trailer.size, size);
 239                 write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
 240                 zip_offset += ZIP64_DATA_DESC_SIZE;
 241         } else {
 242                 struct zip_data_desc trailer;
 243                 copy_le32(trailer.magic, 0x08074b50);
 244                 copy_le32(trailer.crc32, crc);
 245                 copy_le32(trailer.compressed_size, compressed_size);
 246                 copy_le32(trailer.size, size);
 247                 write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 248                 zip_offset += ZIP_DATA_DESC_SIZE;
 249         }
 250 }
 251
 252 static void set_zip_header_data_desc(struct zip_local_header *header,
 253                                      unsigned long size,
 254                                      unsigned long compressed_size,
 255                                      unsigned long crc)
 256 {
 257         copy_le32(header->crc32, crc);
 258         copy_le32(header->compressed_size, compressed_size);
 259         copy_le32(header->size, size);
 260 }
 261
 262 static int has_only_ascii(const char *s)
 263 {
 264         for (;;) {
 265                 int c = *s++;
 266                 if (c == '\0')
 267                         return 1;
 268                 if (!isascii(c))
 269                         return 0;
 270         }
 271 }
 272
 273 static int entry_is_binary(struct index_state *istate, const char *path,
 274                            const void *buffer, size_t size)
 275 {
 276         struct userdiff_driver *driver = userdiff_find_by_path(istate, path);
 277         if (!driver)
 278                 driver = userdiff_find_by_name("default");
 279         if (driver->binary != -1)
 280                 return driver->binary;
 281         return buffer_is_binary(buffer, size);
 282 }
 283
 284 #define STREAM_BUFFER_SIZE (1024 * 16)
 285
 286 static int write_zip_entry(struct archiver_args *args,
 287                            const struct object_id *oid,
 288                            const char *path, size_t pathlen,
 289                            unsigned int mode,
 290                            void *buffer, unsigned long size)
 291 {
 292         struct zip_local_header header;
 293         uintmax_t offset = zip_offset;
 294         struct zip_extra_mtime extra;
 295         struct zip64_extra extra64;
 296         size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
 297         int need_zip64_extra = 0;
 298         unsigned long attr2;
 299         unsigned long compressed_size;
 300         unsigned long crc;
 301         enum zip_method method;
 302         unsigned char *out;
 303         void *deflated = NULL;
 304         struct git_istream *stream = NULL;
 305         unsigned long flags = 0;
 306         int is_binary = -1;
 307         const char *path_without_prefix = path + args->baselen;
 308         unsigned int creator_version = 0;
 309         unsigned int version_needed = 10;
 310         size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
 311         size_t zip64_dir_extra_payload_size = 0;
 312
 313         crc = crc32(0, NULL, 0);
 314
 315         if (!has_only_ascii(path)) {
 316                 if (is_utf8(path))
 317                         flags |= ZIP_UTF8;
 318                 else
 319                         warning(_("path is not valid UTF-8: %s"), path);
 320         }
 321
 322         if (pathlen > 0xffff) {
 323                 return error(_("path too long (%d chars, SHA1: %s): %s"),
 324                                 (int)pathlen, oid_to_hex(oid), path);
 325         }
 326
 327         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 328                 method = ZIP_METHOD_STORE;
 329                 attr2 = 16;
 330                 out = NULL;
 331                 compressed_size = 0;
 332         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 333                 method = ZIP_METHOD_STORE;
 334                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 335                         (mode & 0111) ? ((mode) << 16) : 0;
 336                 if (S_ISLNK(mode) || (mode & 0111))
 337                         creator_version = 0x0317;
 338                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 339                         method = ZIP_METHOD_DEFLATE;
 340
 341                 if (!buffer) {
 342                         enum object_type type;
 343                         stream = open_istream(args->repo, oid, &type, &size,
 344                                               NULL);
 345                         if (!stream)
 346                                 return error(_("cannot stream blob %s"),
 347                                              oid_to_hex(oid));
 348                         flags |= ZIP_STREAM;
 349                         out = NULL;
 350                 } else {
 351                         crc = crc32(crc, buffer, size);
 352                         is_binary = entry_is_binary(args->repo->index,
 353                                                     path_without_prefix,
 354                                                     buffer, size);
 355                         out = buffer;
 356                 }
 357                 compressed_size = (method == ZIP_METHOD_STORE) ? size : 0;
 358         } else {
 359                 return error(_("unsupported file mode: 0%o (SHA1: %s)"), mode,
 360                                 oid_to_hex(oid));
 361         }
 362
 363         if (creator_version > max_creator_version)
 364                 max_creator_version = creator_version;
 365
 366         if (buffer && method == ZIP_METHOD_DEFLATE) {
 367                 out = deflated = zlib_deflate_raw(buffer, size,
 368                                                   args->compression_level,
 369                                                   &compressed_size);
 370                 if (!out || compressed_size >= size) {
 371                         out = buffer;
 372                         method = ZIP_METHOD_STORE;
 373                         compressed_size = size;
 374                 }
 375         }
 376
 377         copy_le16(extra.magic, 0x5455);
 378         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 379         extra.flags[0] = 1;     /* just mtime */
 380         copy_le32(extra.mtime, args->time);
 381
 382         if (size > 0xffffffff || compressed_size > 0xffffffff)
 383                 need_zip64_extra = 1;
 384         if (stream && size > 0x7fffffff)
 385                 need_zip64_extra = 1;
 386
 387         if (need_zip64_extra)
 388                 version_needed = 45;
 389
 390         copy_le32(header.magic, 0x04034b50);
 391         copy_le16(header.version, version_needed);
 392         copy_le16(header.flags, flags);
 393         copy_le16(header.compression_method, method);
 394         copy_le16(header.mtime, zip_time);
 395         copy_le16(header.mdate, zip_date);
 396         if (need_zip64_extra) {
 397                 set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
 398                 header_extra_size += ZIP64_EXTRA_SIZE;
 399         } else {
 400                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 401         }
 402         copy_le16(header.filename_length, pathlen);
 403         copy_le16(header.extra_length, header_extra_size);
 404         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 405         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 406         write_or_die(1, path, pathlen);
 407         zip_offset += pathlen;
 408         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 409         zip_offset += ZIP_EXTRA_MTIME_SIZE;
 410         if (need_zip64_extra) {
 411                 copy_le16(extra64.magic, 0x0001);
 412                 copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
 413                 copy_le64(extra64.size, size);
 414                 copy_le64(extra64.compressed_size, compressed_size);
 415                 write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
 416                 zip_offset += ZIP64_EXTRA_SIZE;
 417         }
 418
 419         if (stream && method == ZIP_METHOD_STORE) {
 420                 unsigned char buf[STREAM_BUFFER_SIZE];
 421                 ssize_t readlen;
 422
 423                 for (;;) {
 424                         readlen = read_istream(stream, buf, sizeof(buf));
 425                         if (readlen <= 0)
 426                                 break;
 427                         crc = crc32(crc, buf, readlen);
 428                         if (is_binary == -1)
 429                                 is_binary = entry_is_binary(args->repo->index,
 430                                                             path_without_prefix,
 431                                                             buf, readlen);
 432                         write_or_die(1, buf, readlen);
 433                 }
 434                 close_istream(stream);
 435                 if (readlen)
 436                         return readlen;
 437
 438                 compressed_size = size;
 439                 zip_offset += compressed_size;
 440
 441                 write_zip_data_desc(size, compressed_size, crc);
 442         } else if (stream && method == ZIP_METHOD_DEFLATE) {
 443                 unsigned char buf[STREAM_BUFFER_SIZE];
 444                 ssize_t readlen;
 445                 git_zstream zstream;
 446                 int result;
 447                 size_t out_len;
 448                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 449
 450                 git_deflate_init_raw(&zstream, args->compression_level);
 451
 452                 compressed_size = 0;
 453                 zstream.next_out = compressed;
 454                 zstream.avail_out = sizeof(compressed);
 455
 456                 for (;;) {
 457                         readlen = read_istream(stream, buf, sizeof(buf));
 458                         if (readlen <= 0)
 459                                 break;
 460                         crc = crc32(crc, buf, readlen);
 461                         if (is_binary == -1)
 462                                 is_binary = entry_is_binary(args->repo->index,
 463                                                             path_without_prefix,
 464                                                             buf, readlen);
 465
 466                         zstream.next_in = buf;
 467                         zstream.avail_in = readlen;
 468                         result = git_deflate(&zstream, 0);
 469                         if (result != Z_OK)
 470                                 die(_("deflate error (%d)"), result);
 471                         out_len = zstream.next_out - compressed;
 472
 473                         if (out_len > 0) {
 474                                 write_or_die(1, compressed, out_len);
 475                                 compressed_size += out_len;
 476                                 zstream.next_out = compressed;
 477                                 zstream.avail_out = sizeof(compressed);
 478                         }
 479
 480                 }
 481                 close_istream(stream);
 482                 if (readlen)
 483                         return readlen;
 484
 485                 zstream.next_in = buf;
 486                 zstream.avail_in = 0;
 487                 result = git_deflate(&zstream, Z_FINISH);
 488                 if (result != Z_STREAM_END)
 489                         die("deflate error (%d)", result);
 490
 491                 git_deflate_end(&zstream);
 492                 out_len = zstream.next_out - compressed;
 493                 write_or_die(1, compressed, out_len);
 494                 compressed_size += out_len;
 495                 zip_offset += compressed_size;
 496
 497                 write_zip_data_desc(size, compressed_size, crc);
 498         } else if (compressed_size > 0) {
 499                 write_or_die(1, out, compressed_size);
 500                 zip_offset += compressed_size;
 501         }
 502
 503         free(deflated);
 504
 505         if (compressed_size > 0xffffffff || size > 0xffffffff ||
 506             offset > 0xffffffff) {
 507                 if (compressed_size >= 0xffffffff)
 508                         zip64_dir_extra_payload_size += 8;
 509                 if (size >= 0xffffffff)
 510                         zip64_dir_extra_payload_size += 8;
 511                 if (offset >= 0xffffffff)
 512                         zip64_dir_extra_payload_size += 8;
 513                 zip_dir_extra_size += 2 + 2 + zip64_dir_extra_payload_size;
 514         }
 515
 516         strbuf_add_le(&zip_dir, 4, 0x02014b50); /* magic */
 517         strbuf_add_le(&zip_dir, 2, creator_version);
 518         strbuf_add_le(&zip_dir, 2, version_needed);
 519         strbuf_add_le(&zip_dir, 2, flags);
 520         strbuf_add_le(&zip_dir, 2, method);
 521         strbuf_add_le(&zip_dir, 2, zip_time);
 522         strbuf_add_le(&zip_dir, 2, zip_date);
 523         strbuf_add_le(&zip_dir, 4, crc);
 524         strbuf_add_le(&zip_dir, 4, clamp32(compressed_size));
 525         strbuf_add_le(&zip_dir, 4, clamp32(size));
 526         strbuf_add_le(&zip_dir, 2, pathlen);
 527         strbuf_add_le(&zip_dir, 2, zip_dir_extra_size);
 528         strbuf_add_le(&zip_dir, 2, 0);          /* comment length */
 529         strbuf_add_le(&zip_dir, 2, 0);          /* disk */
 530         strbuf_add_le(&zip_dir, 2, !is_binary);
 531         strbuf_add_le(&zip_dir, 4, attr2);
 532         strbuf_add_le(&zip_dir, 4, clamp32(offset));
 533         strbuf_add(&zip_dir, path, pathlen);
 534         strbuf_add(&zip_dir, &extra, ZIP_EXTRA_MTIME_SIZE);
 535         if (zip64_dir_extra_payload_size) {
 536                 strbuf_add_le(&zip_dir, 2, 0x0001);     /* magic */
 537                 strbuf_add_le(&zip_dir, 2, zip64_dir_extra_payload_size);
 538                 if (size >= 0xffffffff)
 539                         strbuf_add_le(&zip_dir, 8, size);
 540                 if (compressed_size >= 0xffffffff)
 541                         strbuf_add_le(&zip_dir, 8, compressed_size);
 542                 if (offset >= 0xffffffff)
 543                         strbuf_add_le(&zip_dir, 8, offset);
 544         }
 545         zip_dir_entries++;
 546
 547         return 0;
 548 }
 549
 550 static void write_zip64_trailer(void)
 551 {
 552         struct zip64_dir_trailer trailer64;
 553         struct zip64_dir_trailer_locator locator64;
 554
 555         copy_le32(trailer64.magic, 0x06064b50);
 556         copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
 557         copy_le16(trailer64.creator_version, max_creator_version);
 558         copy_le16(trailer64.version, 45);
 559         copy_le32(trailer64.disk, 0);
 560         copy_le32(trailer64.directory_start_disk, 0);
 561         copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
 562         copy_le64(trailer64.entries, zip_dir_entries);
 563         copy_le64(trailer64.size, zip_dir.len);
 564         copy_le64(trailer64.offset, zip_offset);
 565
 566         copy_le32(locator64.magic, 0x07064b50);
 567         copy_le32(locator64.disk, 0);
 568         copy_le64(locator64.offset, zip_offset + zip_dir.len);
 569         copy_le32(locator64.number_of_disks, 1);
 570
 571         write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
 572         write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
 573 }
 574
 575 static void write_zip_trailer(const struct object_id *oid)
 576 {
 577         struct zip_dir_trailer trailer;
 578         int clamped = 0;
 579
 580         copy_le32(trailer.magic, 0x06054b50);
 581         copy_le16(trailer.disk, 0);
 582         copy_le16(trailer.directory_start_disk, 0);
 583         copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
 584                         &clamped);
 585         copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
 586         copy_le32(trailer.size, zip_dir.len);
 587         copy_le32_clamp(trailer.offset, zip_offset, &clamped);
 588         copy_le16(trailer.comment_length, oid ? the_hash_algo->hexsz : 0);
 589
 590         write_or_die(1, zip_dir.buf, zip_dir.len);
 591         if (clamped)
 592                 write_zip64_trailer();
 593         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 594         if (oid)
 595                 write_or_die(1, oid_to_hex(oid), the_hash_algo->hexsz);
 596 }
 597
 598 static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
 599 {
 600         time_t time;
 601         struct tm tm;
 602
 603         if (date_overflows(*timestamp))
 604                 die(_("timestamp too large for this system: %"PRItime),
 605                     *timestamp);
 606         time = (time_t)*timestamp;
 607         localtime_r(&time, &tm);
 608         *timestamp = time;
 609
 610         *dos_date = tm.tm_mday + (tm.tm_mon + 1) * 32 +
 611                     (tm.tm_year + 1900 - 1980) * 512;
 612         *dos_time = tm.tm_sec / 2 + tm.tm_min * 32 + tm.tm_hour * 2048;
 613 }
 614
 615 static int archive_zip_config(const char *var, const char *value, void *data)
 616 {
 617         return userdiff_config(var, value);
 618 }
 619
 620 static int write_zip_archive(const struct archiver *ar,
 621                              struct archiver_args *args)
 622 {
 623         int err;
 624
 625         git_config(archive_zip_config, NULL);
 626
 627         dos_time(&args->time, &zip_date, &zip_time);
 628
 629         strbuf_init(&zip_dir, 0);
 630
 631         err = write_archive_entries(args, write_zip_entry);
 632         if (!err)
 633                 write_zip_trailer(args->commit_oid);
 634
 635         strbuf_release(&zip_dir);
 636
 637         return err;
 638 }
 639
 640 static struct archiver zip_archiver = {
 641         .name = "zip",
 642         .write_archive = write_zip_archive,
 643         .flags = ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE,
 644 };
 645
 646 void init_zip_archiver(void)
 647 {
 648         register_archiver(&zip_archiver);
 649 }