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
  13 static int zip_date;
  14 static int zip_time;
  15
  16 /* We only care about the "buf" part here. */
  17 static struct strbuf zip_dir;
  18
  19 static uintmax_t zip_offset;
  20 static uint64_t zip_dir_entries;
  21
  22 static unsigned int max_creator_version;
  23
  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 zip64_data_desc {
  51         unsigned char magic[4];
  52         unsigned char crc32[4];
  53         unsigned char compressed_size[8];
  54         unsigned char size[8];
  55         unsigned char _end[1];
  56 };
  57
  58 struct zip_dir_trailer {
  59         unsigned char magic[4];
  60         unsigned char disk[2];
  61         unsigned char directory_start_disk[2];
  62         unsigned char entries_on_this_disk[2];
  63         unsigned char entries[2];
  64         unsigned char size[4];
  65         unsigned char offset[4];
  66         unsigned char comment_length[2];
  67         unsigned char _end[1];
  68 };
  69
  70 struct zip_extra_mtime {
  71         unsigned char magic[2];
  72         unsigned char extra_size[2];
  73         unsigned char flags[1];
  74         unsigned char mtime[4];
  75         unsigned char _end[1];
  76 };
  77
  78 struct zip64_extra {
  79         unsigned char magic[2];
  80         unsigned char extra_size[2];
  81         unsigned char size[8];
  82         unsigned char compressed_size[8];
  83         unsigned char _end[1];
  84 };
  85
  86 struct zip64_dir_trailer {
  87         unsigned char magic[4];
  88         unsigned char record_size[8];
  89         unsigned char creator_version[2];
  90         unsigned char version[2];
  91         unsigned char disk[4];
  92         unsigned char directory_start_disk[4];
  93         unsigned char entries_on_this_disk[8];
  94         unsigned char entries[8];
  95         unsigned char size[8];
  96         unsigned char offset[8];
  97         unsigned char _end[1];
  98 };
  99
 100 struct zip64_dir_trailer_locator {
 101         unsigned char magic[4];
 102         unsigned char disk[4];
 103         unsigned char offset[8];
 104         unsigned char number_of_disks[4];
 105         unsigned char _end[1];
 106 };
 107
 108 /*
 109  * On ARM, padding is added at the end of the struct, so a simple
 110  * sizeof(struct ...) reports two bytes more than the payload size
 111  * we're interested in.
 112  */
 113 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
 114 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
 115 #define ZIP64_DATA_DESC_SIZE    offsetof(struct zip64_data_desc, _end)
 116 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
 117 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
 118 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
 119 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 120         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 121 #define ZIP64_EXTRA_SIZE        offsetof(struct zip64_extra, _end)
 122 #define ZIP64_EXTRA_PAYLOAD_SIZE \
 123         (ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
 124 #define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
 125 #define ZIP64_DIR_TRAILER_RECORD_SIZE \
 126         (ZIP64_DIR_TRAILER_SIZE - \
 127          offsetof(struct zip64_dir_trailer, creator_version))
 128 #define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
 129         offsetof(struct zip64_dir_trailer_locator, _end)
 130
 131 static void copy_le16(unsigned char *dest, unsigned int n)
 132 {
 133         dest[0] = 0xff & n;
 134         dest[1] = 0xff & (n >> 010);
 135 }
 136
 137 static void copy_le32(unsigned char *dest, unsigned int n)
 138 {
 139         dest[0] = 0xff & n;
 140         dest[1] = 0xff & (n >> 010);
 141         dest[2] = 0xff & (n >> 020);
 142         dest[3] = 0xff & (n >> 030);
 143 }
 144
 145 static void copy_le64(unsigned char *dest, uint64_t n)
 146 {
 147         dest[0] = 0xff & n;
 148         dest[1] = 0xff & (n >> 010);
 149         dest[2] = 0xff & (n >> 020);
 150         dest[3] = 0xff & (n >> 030);
 151         dest[4] = 0xff & (n >> 040);
 152         dest[5] = 0xff & (n >> 050);
 153         dest[6] = 0xff & (n >> 060);
 154         dest[7] = 0xff & (n >> 070);
 155 }
 156
 157 static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
 158 {
 159         if (n <= max)
 160                 return n;
 161         *clamped = 1;
 162         return max;
 163 }
 164
 165 static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
 166 {
 167         copy_le16(dest, clamp_max(n, 0xffff, clamped));
 168 }
 169
 170 static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
 171 {
 172         copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
 173 }
 174
 175 static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
 176 {
 177         while (size-- > 0) {
 178                 strbuf_addch(sb, n & 0xff);
 179                 n >>= 8;
 180         }
 181         return -!!n;
 182 }
 183
 184 static uint32_t clamp32(uintmax_t n)
 185 {
 186         const uintmax_t max = 0xffffffff;
 187         return (n < max) ? n : max;
 188 }
 189
 190 static void *zlib_deflate_raw(void *data, unsigned long size,
 191                               int compression_level,
 192                               unsigned long *compressed_size)
 193 {
 194         git_zstream stream;
 195         unsigned long maxsize;
 196         void *buffer;
 197         int result;
 198
 199         git_deflate_init_raw(&stream, compression_level);
 200         maxsize = git_deflate_bound(&stream, size);
 201         buffer = xmalloc(maxsize);
 202
 203         stream.next_in = data;
 204         stream.avail_in = size;
 205         stream.next_out = buffer;
 206         stream.avail_out = maxsize;
 207
 208         do {
 209                 result = git_deflate(&stream, Z_FINISH);
 210         } while (result == Z_OK);
 211
 212         if (result != Z_STREAM_END) {
 213                 free(buffer);
 214                 return NULL;
 215         }
 216
 217         git_deflate_end(&stream);
 218         *compressed_size = stream.total_out;
 219
 220         return buffer;
 221 }
 222
 223 static void write_zip_data_desc(unsigned long size,
 224                                 unsigned long compressed_size,
 225                                 unsigned long crc)
 226 {
 227         if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
 228                 struct zip64_data_desc trailer;
 229                 copy_le32(trailer.magic, 0x08074b50);
 230                 copy_le32(trailer.crc32, crc);
 231                 copy_le64(trailer.compressed_size, compressed_size);
 232                 copy_le64(trailer.size, size);
 233                 write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
 234                 zip_offset += ZIP64_DATA_DESC_SIZE;
 235         } else {
 236                 struct zip_data_desc trailer;
 237                 copy_le32(trailer.magic, 0x08074b50);
 238                 copy_le32(trailer.crc32, crc);
 239                 copy_le32(trailer.compressed_size, compressed_size);
 240                 copy_le32(trailer.size, size);
 241                 write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 242                 zip_offset += ZIP_DATA_DESC_SIZE;
 243         }
 244 }
 245
 246 static void set_zip_header_data_desc(struct zip_local_header *header,
 247                                      unsigned long size,
 248                                      unsigned long compressed_size,
 249                                      unsigned long crc)
 250 {
 251         copy_le32(header->crc32, crc);
 252         copy_le32(header->compressed_size, compressed_size);
 253         copy_le32(header->size, size);
 254 }
 255
 256 static int has_only_ascii(const char *s)
 257 {
 258         for (;;) {
 259                 int c = *s++;
 260                 if (c == '\0')
 261                         return 1;
 262                 if (!isascii(c))
 263                         return 0;
 264         }
 265 }
 266
 267 static int entry_is_binary(struct index_state *istate, const char *path,
 268                            const void *buffer, size_t size)
 269 {
 270         struct userdiff_driver *driver = userdiff_find_by_path(istate, path);
 271         if (!driver)
 272                 driver = userdiff_find_by_name("default");
 273         if (driver->binary != -1)
 274                 return driver->binary;
 275         return buffer_is_binary(buffer, size);
 276 }
 277
 278 #define STREAM_BUFFER_SIZE (1024 * 16)
 279
 280 static int write_zip_entry(struct archiver_args *args,
 281                            const struct object_id *oid,
 282                            const char *path, size_t pathlen,
 283                            unsigned int mode)
 284 {
 285         struct zip_local_header header;
 286         uintmax_t offset = zip_offset;
 287         struct zip_extra_mtime extra;
 288         struct zip64_extra extra64;
 289         size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
 290         int need_zip64_extra = 0;
 291         unsigned long attr2;
 292         unsigned long compressed_size;
 293         unsigned long crc;
 294         int method;
 295         unsigned char *out;
 296         void *deflated = NULL;
 297         void *buffer;
 298         struct git_istream *stream = NULL;
 299         unsigned long flags = 0;
 300         unsigned long size;
 301         int is_binary = -1;
 302         const char *path_without_prefix = path + args->baselen;
 303         unsigned int creator_version = 0;
 304         unsigned int version_needed = 10;
 305         size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
 306         size_t zip64_dir_extra_payload_size = 0;
 307
 308         crc = crc32(0, NULL, 0);
 309
 310         if (!has_only_ascii(path)) {
 311                 if (is_utf8(path))
 312                         flags |= ZIP_UTF8;
 313                 else
 314                         warning(_("path is not valid UTF-8: %s"), path);
 315         }
 316
 317         if (pathlen > 0xffff) {
 318                 return error(_("path too long (%d chars, SHA1: %s): %s"),
 319                                 (int)pathlen, oid_to_hex(oid), path);
 320         }
 321
 322         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 323                 method = 0;
 324                 attr2 = 16;
 325                 out = NULL;
 326                 size = 0;
 327                 compressed_size = 0;
 328                 buffer = NULL;
 329         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 330                 enum object_type type = oid_object_info(args->repo, oid,
 331                                                         &size);
 332
 333                 method = 0;
 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 = 8;
 340
 341                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 342                     size > big_file_threshold) {
 343                         stream = open_istream(oid, &type, &size, NULL);
 344                         if (!stream)
 345                                 return error(_("cannot stream blob %s"),
 346                                              oid_to_hex(oid));
 347                         flags |= ZIP_STREAM;
 348                         out = buffer = NULL;
 349                 } else {
 350                         buffer = object_file_to_archive(args, path, oid, mode,
 351                                                         &type, &size);
 352                         if (!buffer)
 353                                 return error(_("cannot read %s"),
 354                                              oid_to_hex(oid));
 355                         crc = crc32(crc, buffer, size);
 356                         is_binary = entry_is_binary(args->repo->index,
 357                                                     path_without_prefix,
 358                                                     buffer, size);
 359                         out = buffer;
 360                 }
 361                 compressed_size = (method == 0) ? size : 0;
 362         } else {
 363                 return error(_("unsupported file mode: 0%o (SHA1: %s)"), mode,
 364                                 oid_to_hex(oid));
 365         }
 366
 367         if (creator_version > max_creator_version)
 368                 max_creator_version = creator_version;
 369
 370         if (buffer && method == 8) {
 371                 out = deflated = zlib_deflate_raw(buffer, size,
 372                                                   args->compression_level,
 373                                                   &compressed_size);
 374                 if (!out || compressed_size >= size) {
 375                         out = buffer;
 376                         method = 0;
 377                         compressed_size = size;
 378                 }
 379         }
 380
 381         copy_le16(extra.magic, 0x5455);
 382         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 383         extra.flags[0] = 1;     /* just mtime */
 384         copy_le32(extra.mtime, args->time);
 385
 386         if (size > 0xffffffff || compressed_size > 0xffffffff)
 387                 need_zip64_extra = 1;
 388         if (stream && size > 0x7fffffff)
 389                 need_zip64_extra = 1;
 390
 391         if (need_zip64_extra)
 392                 version_needed = 45;
 393
 394         copy_le32(header.magic, 0x04034b50);
 395         copy_le16(header.version, version_needed);
 396         copy_le16(header.flags, flags);
 397         copy_le16(header.compression_method, method);
 398         copy_le16(header.mtime, zip_time);
 399         copy_le16(header.mdate, zip_date);
 400         if (need_zip64_extra) {
 401                 set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
 402                 header_extra_size += ZIP64_EXTRA_SIZE;
 403         } else {
 404                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 405         }
 406         copy_le16(header.filename_length, pathlen);
 407         copy_le16(header.extra_length, header_extra_size);
 408         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 409         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 410         write_or_die(1, path, pathlen);
 411         zip_offset += pathlen;
 412         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 413         zip_offset += ZIP_EXTRA_MTIME_SIZE;
 414         if (need_zip64_extra) {
 415                 copy_le16(extra64.magic, 0x0001);
 416                 copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
 417                 copy_le64(extra64.size, size);
 418                 copy_le64(extra64.compressed_size, compressed_size);
 419                 write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
 420                 zip_offset += ZIP64_EXTRA_SIZE;
 421         }
 422
 423         if (stream && method == 0) {
 424                 unsigned char buf[STREAM_BUFFER_SIZE];
 425                 ssize_t readlen;
 426
 427                 for (;;) {
 428                         readlen = read_istream(stream, buf, sizeof(buf));
 429                         if (readlen <= 0)
 430                                 break;
 431                         crc = crc32(crc, buf, readlen);
 432                         if (is_binary == -1)
 433                                 is_binary = entry_is_binary(args->repo->index,
 434                                                             path_without_prefix,
 435                                                             buf, readlen);
 436                         write_or_die(1, buf, readlen);
 437                 }
 438                 close_istream(stream);
 439                 if (readlen)
 440                         return readlen;
 441
 442                 compressed_size = size;
 443                 zip_offset += compressed_size;
 444
 445                 write_zip_data_desc(size, compressed_size, crc);
 446         } else if (stream && method == 8) {
 447                 unsigned char buf[STREAM_BUFFER_SIZE];
 448                 ssize_t readlen;
 449                 git_zstream zstream;
 450                 int result;
 451                 size_t out_len;
 452                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 453
 454                 git_deflate_init_raw(&zstream, args->compression_level);
 455
 456                 compressed_size = 0;
 457                 zstream.next_out = compressed;
 458                 zstream.avail_out = sizeof(compressed);
 459
 460                 for (;;) {
 461                         readlen = read_istream(stream, buf, sizeof(buf));
 462                         if (readlen <= 0)
 463                                 break;
 464                         crc = crc32(crc, buf, readlen);
 465                         if (is_binary == -1)
 466                                 is_binary = entry_is_binary(args->repo->index,
 467                                                             path_without_prefix,
 468                                                             buf, readlen);
 469
 470                         zstream.next_in = buf;
 471                         zstream.avail_in = readlen;
 472                         result = git_deflate(&zstream, 0);
 473                         if (result != Z_OK)
 474                                 die(_("deflate error (%d)"), result);
 475                         out_len = zstream.next_out - compressed;
 476
 477                         if (out_len > 0) {
 478                                 write_or_die(1, compressed, out_len);
 479                                 compressed_size += out_len;
 480                                 zstream.next_out = compressed;
 481                                 zstream.avail_out = sizeof(compressed);
 482                         }
 483
 484                 }
 485                 close_istream(stream);
 486                 if (readlen)
 487                         return readlen;
 488
 489                 zstream.next_in = buf;
 490                 zstream.avail_in = 0;
 491                 result = git_deflate(&zstream, Z_FINISH);
 492                 if (result != Z_STREAM_END)
 493                         die("deflate error (%d)", result);
 494
 495                 git_deflate_end(&zstream);
 496                 out_len = zstream.next_out - compressed;
 497                 write_or_die(1, compressed, out_len);
 498                 compressed_size += out_len;
 499                 zip_offset += compressed_size;
 500
 501                 write_zip_data_desc(size, compressed_size, crc);
 502         } else if (compressed_size > 0) {
 503                 write_or_die(1, out, compressed_size);
 504                 zip_offset += compressed_size;
 505         }
 506
 507         free(deflated);
 508         free(buffer);
 509
 510         if (compressed_size > 0xffffffff || size > 0xffffffff ||
 511             offset > 0xffffffff) {
 512                 if (compressed_size >= 0xffffffff)
 513                         zip64_dir_extra_payload_size += 8;
 514                 if (size >= 0xffffffff)
 515                         zip64_dir_extra_payload_size += 8;
 516                 if (offset >= 0xffffffff)
 517                         zip64_dir_extra_payload_size += 8;
 518                 zip_dir_extra_size += 2 + 2 + zip64_dir_extra_payload_size;
 519         }
 520
 521         strbuf_add_le(&zip_dir, 4, 0x02014b50); /* magic */
 522         strbuf_add_le(&zip_dir, 2, creator_version);
 523         strbuf_add_le(&zip_dir, 2, version_needed);
 524         strbuf_add_le(&zip_dir, 2, flags);
 525         strbuf_add_le(&zip_dir, 2, method);
 526         strbuf_add_le(&zip_dir, 2, zip_time);
 527         strbuf_add_le(&zip_dir, 2, zip_date);
 528         strbuf_add_le(&zip_dir, 4, crc);
 529         strbuf_add_le(&zip_dir, 4, clamp32(compressed_size));
 530         strbuf_add_le(&zip_dir, 4, clamp32(size));
 531         strbuf_add_le(&zip_dir, 2, pathlen);
 532         strbuf_add_le(&zip_dir, 2, zip_dir_extra_size);
 533         strbuf_add_le(&zip_dir, 2, 0);          /* comment length */
 534         strbuf_add_le(&zip_dir, 2, 0);          /* disk */
 535         strbuf_add_le(&zip_dir, 2, !is_binary);
 536         strbuf_add_le(&zip_dir, 4, attr2);
 537         strbuf_add_le(&zip_dir, 4, clamp32(offset));
 538         strbuf_add(&zip_dir, path, pathlen);
 539         strbuf_add(&zip_dir, &extra, ZIP_EXTRA_MTIME_SIZE);
 540         if (zip64_dir_extra_payload_size) {
 541                 strbuf_add_le(&zip_dir, 2, 0x0001);     /* magic */
 542                 strbuf_add_le(&zip_dir, 2, zip64_dir_extra_payload_size);
 543                 if (size >= 0xffffffff)
 544                         strbuf_add_le(&zip_dir, 8, size);
 545                 if (compressed_size >= 0xffffffff)
 546                         strbuf_add_le(&zip_dir, 8, compressed_size);
 547                 if (offset >= 0xffffffff)
 548                         strbuf_add_le(&zip_dir, 8, offset);
 549         }
 550         zip_dir_entries++;
 551
 552         return 0;
 553 }
 554
 555 static void write_zip64_trailer(void)
 556 {
 557         struct zip64_dir_trailer trailer64;
 558         struct zip64_dir_trailer_locator locator64;
 559
 560         copy_le32(trailer64.magic, 0x06064b50);
 561         copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
 562         copy_le16(trailer64.creator_version, max_creator_version);
 563         copy_le16(trailer64.version, 45);
 564         copy_le32(trailer64.disk, 0);
 565         copy_le32(trailer64.directory_start_disk, 0);
 566         copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
 567         copy_le64(trailer64.entries, zip_dir_entries);
 568         copy_le64(trailer64.size, zip_dir.len);
 569         copy_le64(trailer64.offset, zip_offset);
 570
 571         copy_le32(locator64.magic, 0x07064b50);
 572         copy_le32(locator64.disk, 0);
 573         copy_le64(locator64.offset, zip_offset + zip_dir.len);
 574         copy_le32(locator64.number_of_disks, 1);
 575
 576         write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
 577         write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
 578 }
 579
 580 static void write_zip_trailer(const struct object_id *oid)
 581 {
 582         struct zip_dir_trailer trailer;
 583         int clamped = 0;
 584
 585         copy_le32(trailer.magic, 0x06054b50);
 586         copy_le16(trailer.disk, 0);
 587         copy_le16(trailer.directory_start_disk, 0);
 588         copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
 589                         &clamped);
 590         copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
 591         copy_le32(trailer.size, zip_dir.len);
 592         copy_le32_clamp(trailer.offset, zip_offset, &clamped);
 593         copy_le16(trailer.comment_length, oid ? the_hash_algo->hexsz : 0);
 594
 595         write_or_die(1, zip_dir.buf, zip_dir.len);
 596         if (clamped)
 597                 write_zip64_trailer();
 598         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 599         if (oid)
 600                 write_or_die(1, oid_to_hex(oid), the_hash_algo->hexsz);
 601 }
 602
 603 static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
 604 {
 605         time_t time;
 606         struct tm *t;
 607
 608         if (date_overflows(*timestamp))
 609                 die(_("timestamp too large for this system: %"PRItime),
 610                     *timestamp);
 611         time = (time_t)*timestamp;
 612         t = localtime(&time);
 613         *timestamp = time;
 614
 615         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 616                     (t->tm_year + 1900 - 1980) * 512;
 617         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 618 }
 619
 620 static int archive_zip_config(const char *var, const char *value, void *data)
 621 {
 622         return userdiff_config(var, value);
 623 }
 624
 625 static int write_zip_archive(const struct archiver *ar,
 626                              struct archiver_args *args)
 627 {
 628         int err;
 629
 630         git_config(archive_zip_config, NULL);
 631
 632         dos_time(&args->time, &zip_date, &zip_time);
 633
 634         strbuf_init(&zip_dir, 0);
 635
 636         err = write_archive_entries(args, write_zip_entry);
 637         if (!err)
 638                 write_zip_trailer(args->commit_oid);
 639
 640         strbuf_release(&zip_dir);
 641
 642         return err;
 643 }
 644
 645 static struct archiver zip_archiver = {
 646         "zip",
 647         write_zip_archive,
 648         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 649 };
 650
 651 void init_zip_archiver(void)
 652 {
 653         register_archiver(&zip_archiver);
 654 }