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 "gettext.h"
   8 #include "hex.h"
   9 #include "streaming.h"
  10 #include "utf8.h"
  11 #include "object-store.h"
  12 #include "userdiff.h"
  13 #include "write-or-die.h"
  14 #include "xdiff-interface.h"
  15 #include "date.h"
  16
  17 static int zip_date;
  18 static int zip_time;
  19
  20 /* We only care about the "buf" part here. */
  21 static struct strbuf zip_dir;
  22
  23 static uintmax_t zip_offset;
  24 static uint64_t zip_dir_entries;
  25
  26 static unsigned int max_creator_version;
  27
  28 #define ZIP_STREAM      (1 <<  3)
  29 #define ZIP_UTF8        (1 << 11)
  30
  31 enum zip_method {
  32         ZIP_METHOD_STORE = 0,
  33         ZIP_METHOD_DEFLATE = 8
  34 };
  35
  36 struct zip_local_header {
  37         unsigned char magic[4];
  38         unsigned char version[2];
  39         unsigned char flags[2];
  40         unsigned char compression_method[2];
  41         unsigned char mtime[2];
  42         unsigned char mdate[2];
  43         unsigned char crc32[4];
  44         unsigned char compressed_size[4];
  45         unsigned char size[4];
  46         unsigned char filename_length[2];
  47         unsigned char extra_length[2];
  48         unsigned char _end[1];
  49 };
  50
  51 struct zip_data_desc {
  52         unsigned char magic[4];
  53         unsigned char crc32[4];
  54         unsigned char compressed_size[4];
  55         unsigned char size[4];
  56         unsigned char _end[1];
  57 };
  58
  59 struct zip64_data_desc {
  60         unsigned char magic[4];
  61         unsigned char crc32[4];
  62         unsigned char compressed_size[8];
  63         unsigned char size[8];
  64         unsigned char _end[1];
  65 };
  66
  67 struct zip_dir_trailer {
  68         unsigned char magic[4];
  69         unsigned char disk[2];
  70         unsigned char directory_start_disk[2];
  71         unsigned char entries_on_this_disk[2];
  72         unsigned char entries[2];
  73         unsigned char size[4];
  74         unsigned char offset[4];
  75         unsigned char comment_length[2];
  76         unsigned char _end[1];
  77 };
  78
  79 struct zip_extra_mtime {
  80         unsigned char magic[2];
  81         unsigned char extra_size[2];
  82         unsigned char flags[1];
  83         unsigned char mtime[4];
  84         unsigned char _end[1];
  85 };
  86
  87 struct zip64_extra {
  88         unsigned char magic[2];
  89         unsigned char extra_size[2];
  90         unsigned char size[8];
  91         unsigned char compressed_size[8];
  92         unsigned char _end[1];
  93 };
  94
  95 struct zip64_dir_trailer {
  96         unsigned char magic[4];
  97         unsigned char record_size[8];
  98         unsigned char creator_version[2];
  99         unsigned char version[2];
 100         unsigned char disk[4];
 101         unsigned char directory_start_disk[4];
 102         unsigned char entries_on_this_disk[8];
 103         unsigned char entries[8];
 104         unsigned char size[8];
 105         unsigned char offset[8];
 106         unsigned char _end[1];
 107 };
 108
 109 struct zip64_dir_trailer_locator {
 110         unsigned char magic[4];
 111         unsigned char disk[4];
 112         unsigned char offset[8];
 113         unsigned char number_of_disks[4];
 114         unsigned char _end[1];
 115 };
 116
 117 /*
 118  * On ARM, padding is added at the end of the struct, so a simple
 119  * sizeof(struct ...) reports two bytes more than the payload size
 120  * we're interested in.
 121  */
 122 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
 123 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
 124 #define ZIP64_DATA_DESC_SIZE    offsetof(struct zip64_data_desc, _end)
 125 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
 126 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
 127 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
 128 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 129         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 130 #define ZIP64_EXTRA_SIZE        offsetof(struct zip64_extra, _end)
 131 #define ZIP64_EXTRA_PAYLOAD_SIZE \
 132         (ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
 133 #define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
 134 #define ZIP64_DIR_TRAILER_RECORD_SIZE \
 135         (ZIP64_DIR_TRAILER_SIZE - \
 136          offsetof(struct zip64_dir_trailer, creator_version))
 137 #define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
 138         offsetof(struct zip64_dir_trailer_locator, _end)
 139
 140 static void copy_le16(unsigned char *dest, unsigned int n)
 141 {
 142         dest[0] = 0xff & n;
 143         dest[1] = 0xff & (n >> 010);
 144 }
 145
 146 static void copy_le32(unsigned char *dest, unsigned int 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 }
 153
 154 static void copy_le64(unsigned char *dest, uint64_t n)
 155 {
 156         dest[0] = 0xff & n;
 157         dest[1] = 0xff & (n >> 010);
 158         dest[2] = 0xff & (n >> 020);
 159         dest[3] = 0xff & (n >> 030);
 160         dest[4] = 0xff & (n >> 040);
 161         dest[5] = 0xff & (n >> 050);
 162         dest[6] = 0xff & (n >> 060);
 163         dest[7] = 0xff & (n >> 070);
 164 }
 165
 166 static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
 167 {
 168         if (n <= max)
 169                 return n;
 170         *clamped = 1;
 171         return max;
 172 }
 173
 174 static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
 175 {
 176         copy_le16(dest, clamp_max(n, 0xffff, clamped));
 177 }
 178
 179 static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
 180 {
 181         copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
 182 }
 183
 184 static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
 185 {
 186         while (size-- > 0) {
 187                 strbuf_addch(sb, n & 0xff);
 188                 n >>= 8;
 189         }
 190         return -!!n;
 191 }
 192
 193 static uint32_t clamp32(uintmax_t n)
 194 {
 195         const uintmax_t max = 0xffffffff;
 196         return (n < max) ? n : max;
 197 }
 198
 199 static void *zlib_deflate_raw(void *data, unsigned long size,
 200                               int compression_level,
 201                               unsigned long *compressed_size)
 202 {
 203         git_zstream stream;
 204         unsigned long maxsize;
 205         void *buffer;
 206         int result;
 207
 208         git_deflate_init_raw(&stream, compression_level);
 209         maxsize = git_deflate_bound(&stream, size);
 210         buffer = xmalloc(maxsize);
 211
 212         stream.next_in = data;
 213         stream.avail_in = size;
 214         stream.next_out = buffer;
 215         stream.avail_out = maxsize;
 216
 217         do {
 218                 result = git_deflate(&stream, Z_FINISH);
 219         } while (result == Z_OK);
 220
 221         if (result != Z_STREAM_END) {
 222                 free(buffer);
 223                 return NULL;
 224         }
 225
 226         git_deflate_end(&stream);
 227         *compressed_size = stream.total_out;
 228
 229         return buffer;
 230 }
 231
 232 static void write_zip_data_desc(unsigned long size,
 233                                 unsigned long compressed_size,
 234                                 unsigned long crc)
 235 {
 236         if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
 237                 struct zip64_data_desc trailer;
 238                 copy_le32(trailer.magic, 0x08074b50);
 239                 copy_le32(trailer.crc32, crc);
 240                 copy_le64(trailer.compressed_size, compressed_size);
 241                 copy_le64(trailer.size, size);
 242                 write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
 243                 zip_offset += ZIP64_DATA_DESC_SIZE;
 244         } else {
 245                 struct zip_data_desc trailer;
 246                 copy_le32(trailer.magic, 0x08074b50);
 247                 copy_le32(trailer.crc32, crc);
 248                 copy_le32(trailer.compressed_size, compressed_size);
 249                 copy_le32(trailer.size, size);
 250                 write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 251                 zip_offset += ZIP_DATA_DESC_SIZE;
 252         }
 253 }
 254
 255 static void set_zip_header_data_desc(struct zip_local_header *header,
 256                                      unsigned long size,
 257                                      unsigned long compressed_size,
 258                                      unsigned long crc)
 259 {
 260         copy_le32(header->crc32, crc);
 261         copy_le32(header->compressed_size, compressed_size);
 262         copy_le32(header->size, size);
 263 }
 264
 265 static int has_only_ascii(const char *s)
 266 {
 267         for (;;) {
 268                 int c = *s++;
 269                 if (c == '\0')
 270                         return 1;
 271                 if (!isascii(c))
 272                         return 0;
 273         }
 274 }
 275
 276 static int entry_is_binary(struct index_state *istate, const char *path,
 277                            const void *buffer, size_t size)
 278 {
 279         struct userdiff_driver *driver = userdiff_find_by_path(istate, path);
 280         if (!driver)
 281                 driver = userdiff_find_by_name("default");
 282         if (driver->binary != -1)
 283                 return driver->binary;
 284         return buffer_is_binary(buffer, size);
 285 }
 286
 287 #define STREAM_BUFFER_SIZE (1024 * 16)
 288
 289 static int write_zip_entry(struct archiver_args *args,
 290                            const struct object_id *oid,
 291                            const char *path, size_t pathlen,
 292                            unsigned int mode,
 293                            void *buffer, unsigned long size)
 294 {
 295         struct zip_local_header header;
 296         uintmax_t offset = zip_offset;
 297         struct zip_extra_mtime extra;
 298         struct zip64_extra extra64;
 299         size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
 300         int need_zip64_extra = 0;
 301         unsigned long attr2;
 302         unsigned long compressed_size;
 303         unsigned long crc;
 304         enum zip_method method;
 305         unsigned char *out;
 306         void *deflated = NULL;
 307         struct git_istream *stream = NULL;
 308         unsigned long flags = 0;
 309         int is_binary = -1;
 310         const char *path_without_prefix = path + args->baselen;
 311         unsigned int creator_version = 0;
 312         unsigned int version_needed = 10;
 313         size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
 314         size_t zip64_dir_extra_payload_size = 0;
 315
 316         crc = crc32(0, NULL, 0);
 317
 318         if (!has_only_ascii(path)) {
 319                 if (is_utf8(path))
 320                         flags |= ZIP_UTF8;
 321                 else
 322                         warning(_("path is not valid UTF-8: %s"), path);
 323         }
 324
 325         if (pathlen > 0xffff) {
 326                 return error(_("path too long (%d chars, SHA1: %s): %s"),
 327                                 (int)pathlen, oid_to_hex(oid), path);
 328         }
 329
 330         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 331                 method = ZIP_METHOD_STORE;
 332                 attr2 = 16;
 333                 out = NULL;
 334                 compressed_size = 0;
 335         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 336                 method = ZIP_METHOD_STORE;
 337                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 338                         (mode & 0111) ? ((mode) << 16) : 0;
 339                 if (S_ISLNK(mode) || (mode & 0111))
 340                         creator_version = 0x0317;
 341                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 342                         method = ZIP_METHOD_DEFLATE;
 343
 344                 if (!buffer) {
 345                         enum object_type type;
 346                         stream = open_istream(args->repo, oid, &type, &size,
 347                                               NULL);
 348                         if (!stream)
 349                                 return error(_("cannot stream blob %s"),
 350                                              oid_to_hex(oid));
 351                         flags |= ZIP_STREAM;
 352                         out = NULL;
 353                 } else {
 354                         crc = crc32(crc, buffer, size);
 355                         is_binary = entry_is_binary(args->repo->index,
 356                                                     path_without_prefix,
 357                                                     buffer, size);
 358                         out = buffer;
 359                 }
 360                 compressed_size = (method == ZIP_METHOD_STORE) ? size : 0;
 361         } else {
 362                 return error(_("unsupported file mode: 0%o (SHA1: %s)"), mode,
 363                                 oid_to_hex(oid));
 364         }
 365
 366         if (creator_version > max_creator_version)
 367                 max_creator_version = creator_version;
 368
 369         if (buffer && method == ZIP_METHOD_DEFLATE) {
 370                 out = deflated = zlib_deflate_raw(buffer, size,
 371                                                   args->compression_level,
 372                                                   &compressed_size);
 373                 if (!out || compressed_size >= size) {
 374                         out = buffer;
 375                         method = ZIP_METHOD_STORE;
 376                         compressed_size = size;
 377                 }
 378         }
 379
 380         copy_le16(extra.magic, 0x5455);
 381         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 382         extra.flags[0] = 1;     /* just mtime */
 383         copy_le32(extra.mtime, args->time);
 384
 385         if (size > 0xffffffff || compressed_size > 0xffffffff)
 386                 need_zip64_extra = 1;
 387         if (stream && size > 0x7fffffff)
 388                 need_zip64_extra = 1;
 389
 390         if (need_zip64_extra)
 391                 version_needed = 45;
 392
 393         copy_le32(header.magic, 0x04034b50);
 394         copy_le16(header.version, version_needed);
 395         copy_le16(header.flags, flags);
 396         copy_le16(header.compression_method, method);
 397         copy_le16(header.mtime, zip_time);
 398         copy_le16(header.mdate, zip_date);
 399         if (need_zip64_extra) {
 400                 set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
 401                 header_extra_size += ZIP64_EXTRA_SIZE;
 402         } else {
 403                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 404         }
 405         copy_le16(header.filename_length, pathlen);
 406         copy_le16(header.extra_length, header_extra_size);
 407         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 408         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 409         write_or_die(1, path, pathlen);
 410         zip_offset += pathlen;
 411         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 412         zip_offset += ZIP_EXTRA_MTIME_SIZE;
 413         if (need_zip64_extra) {
 414                 copy_le16(extra64.magic, 0x0001);
 415                 copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
 416                 copy_le64(extra64.size, size);
 417                 copy_le64(extra64.compressed_size, compressed_size);
 418                 write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
 419                 zip_offset += ZIP64_EXTRA_SIZE;
 420         }
 421
 422         if (stream && method == ZIP_METHOD_STORE) {
 423                 unsigned char buf[STREAM_BUFFER_SIZE];
 424                 ssize_t readlen;
 425
 426                 for (;;) {
 427                         readlen = read_istream(stream, buf, sizeof(buf));
 428                         if (readlen <= 0)
 429                                 break;
 430                         crc = crc32(crc, buf, readlen);
 431                         if (is_binary == -1)
 432                                 is_binary = entry_is_binary(args->repo->index,
 433                                                             path_without_prefix,
 434                                                             buf, readlen);
 435                         write_or_die(1, buf, readlen);
 436                 }
 437                 close_istream(stream);
 438                 if (readlen)
 439                         return readlen;
 440
 441                 compressed_size = size;
 442                 zip_offset += compressed_size;
 443
 444                 write_zip_data_desc(size, compressed_size, crc);
 445         } else if (stream && method == ZIP_METHOD_DEFLATE) {
 446                 unsigned char buf[STREAM_BUFFER_SIZE];
 447                 ssize_t readlen;
 448                 git_zstream zstream;
 449                 int result;
 450                 size_t out_len;
 451                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 452
 453                 git_deflate_init_raw(&zstream, args->compression_level);
 454
 455                 compressed_size = 0;
 456                 zstream.next_out = compressed;
 457                 zstream.avail_out = sizeof(compressed);
 458
 459                 for (;;) {
 460                         readlen = read_istream(stream, buf, sizeof(buf));
 461                         if (readlen <= 0)
 462                                 break;
 463                         crc = crc32(crc, buf, readlen);
 464                         if (is_binary == -1)
 465                                 is_binary = entry_is_binary(args->repo->index,
 466                                                             path_without_prefix,
 467                                                             buf, readlen);
 468
 469                         zstream.next_in = buf;
 470                         zstream.avail_in = readlen;
 471                         result = git_deflate(&zstream, 0);
 472                         if (result != Z_OK)
 473                                 die(_("deflate error (%d)"), result);
 474                         out_len = zstream.next_out - compressed;
 475
 476                         if (out_len > 0) {
 477                                 write_or_die(1, compressed, out_len);
 478                                 compressed_size += out_len;
 479                                 zstream.next_out = compressed;
 480                                 zstream.avail_out = sizeof(compressed);
 481                         }
 482
 483                 }
 484                 close_istream(stream);
 485                 if (readlen)
 486                         return readlen;
 487
 488                 zstream.next_in = buf;
 489                 zstream.avail_in = 0;
 490                 result = git_deflate(&zstream, Z_FINISH);
 491                 if (result != Z_STREAM_END)
 492                         die("deflate error (%d)", result);
 493
 494                 git_deflate_end(&zstream);
 495                 out_len = zstream.next_out - compressed;
 496                 write_or_die(1, compressed, out_len);
 497                 compressed_size += out_len;
 498                 zip_offset += compressed_size;
 499
 500                 write_zip_data_desc(size, compressed_size, crc);
 501         } else if (compressed_size > 0) {
 502                 write_or_die(1, out, compressed_size);
 503                 zip_offset += compressed_size;
 504         }
 505
 506         free(deflated);
 507
 508         if (compressed_size > 0xffffffff || size > 0xffffffff ||
 509             offset > 0xffffffff) {
 510                 if (compressed_size >= 0xffffffff)
 511                         zip64_dir_extra_payload_size += 8;
 512                 if (size >= 0xffffffff)
 513                         zip64_dir_extra_payload_size += 8;
 514                 if (offset >= 0xffffffff)
 515                         zip64_dir_extra_payload_size += 8;
 516                 zip_dir_extra_size += 2 + 2 + zip64_dir_extra_payload_size;
 517         }
 518
 519         strbuf_add_le(&zip_dir, 4, 0x02014b50); /* magic */
 520         strbuf_add_le(&zip_dir, 2, creator_version);
 521         strbuf_add_le(&zip_dir, 2, version_needed);
 522         strbuf_add_le(&zip_dir, 2, flags);
 523         strbuf_add_le(&zip_dir, 2, method);
 524         strbuf_add_le(&zip_dir, 2, zip_time);
 525         strbuf_add_le(&zip_dir, 2, zip_date);
 526         strbuf_add_le(&zip_dir, 4, crc);
 527         strbuf_add_le(&zip_dir, 4, clamp32(compressed_size));
 528         strbuf_add_le(&zip_dir, 4, clamp32(size));
 529         strbuf_add_le(&zip_dir, 2, pathlen);
 530         strbuf_add_le(&zip_dir, 2, zip_dir_extra_size);
 531         strbuf_add_le(&zip_dir, 2, 0);          /* comment length */
 532         strbuf_add_le(&zip_dir, 2, 0);          /* disk */
 533         strbuf_add_le(&zip_dir, 2, !is_binary);
 534         strbuf_add_le(&zip_dir, 4, attr2);
 535         strbuf_add_le(&zip_dir, 4, clamp32(offset));
 536         strbuf_add(&zip_dir, path, pathlen);
 537         strbuf_add(&zip_dir, &extra, ZIP_EXTRA_MTIME_SIZE);
 538         if (zip64_dir_extra_payload_size) {
 539                 strbuf_add_le(&zip_dir, 2, 0x0001);     /* magic */
 540                 strbuf_add_le(&zip_dir, 2, zip64_dir_extra_payload_size);
 541                 if (size >= 0xffffffff)
 542                         strbuf_add_le(&zip_dir, 8, size);
 543                 if (compressed_size >= 0xffffffff)
 544                         strbuf_add_le(&zip_dir, 8, compressed_size);
 545                 if (offset >= 0xffffffff)
 546                         strbuf_add_le(&zip_dir, 8, offset);
 547         }
 548         zip_dir_entries++;
 549
 550         return 0;
 551 }
 552
 553 static void write_zip64_trailer(void)
 554 {
 555         struct zip64_dir_trailer trailer64;
 556         struct zip64_dir_trailer_locator locator64;
 557
 558         copy_le32(trailer64.magic, 0x06064b50);
 559         copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
 560         copy_le16(trailer64.creator_version, max_creator_version);
 561         copy_le16(trailer64.version, 45);
 562         copy_le32(trailer64.disk, 0);
 563         copy_le32(trailer64.directory_start_disk, 0);
 564         copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
 565         copy_le64(trailer64.entries, zip_dir_entries);
 566         copy_le64(trailer64.size, zip_dir.len);
 567         copy_le64(trailer64.offset, zip_offset);
 568
 569         copy_le32(locator64.magic, 0x07064b50);
 570         copy_le32(locator64.disk, 0);
 571         copy_le64(locator64.offset, zip_offset + zip_dir.len);
 572         copy_le32(locator64.number_of_disks, 1);
 573
 574         write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
 575         write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
 576 }
 577
 578 static void write_zip_trailer(const struct object_id *oid)
 579 {
 580         struct zip_dir_trailer trailer;
 581         int clamped = 0;
 582
 583         copy_le32(trailer.magic, 0x06054b50);
 584         copy_le16(trailer.disk, 0);
 585         copy_le16(trailer.directory_start_disk, 0);
 586         copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
 587                         &clamped);
 588         copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
 589         copy_le32(trailer.size, zip_dir.len);
 590         copy_le32_clamp(trailer.offset, zip_offset, &clamped);
 591         copy_le16(trailer.comment_length, oid ? the_hash_algo->hexsz : 0);
 592
 593         write_or_die(1, zip_dir.buf, zip_dir.len);
 594         if (clamped)
 595                 write_zip64_trailer();
 596         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 597         if (oid)
 598                 write_or_die(1, oid_to_hex(oid), the_hash_algo->hexsz);
 599 }
 600
 601 static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
 602 {
 603         time_t time;
 604         struct tm tm;
 605
 606         if (date_overflows(*timestamp))
 607                 die(_("timestamp too large for this system: %"PRItime),
 608                     *timestamp);
 609         time = (time_t)*timestamp;
 610         localtime_r(&time, &tm);
 611         *timestamp = time;
 612
 613         *dos_date = tm.tm_mday + (tm.tm_mon + 1) * 32 +
 614                     (tm.tm_year + 1900 - 1980) * 512;
 615         *dos_time = tm.tm_sec / 2 + tm.tm_min * 32 + tm.tm_hour * 2048;
 616 }
 617
 618 static int archive_zip_config(const char *var, const char *value,
 619                               void *data UNUSED)
 620 {
 621         return userdiff_config(var, value);
 622 }
 623
 624 static int write_zip_archive(const struct archiver *ar UNUSED,
 625                              struct archiver_args *args)
 626 {
 627         int err;
 628
 629         git_config(archive_zip_config, NULL);
 630
 631         dos_time(&args->time, &zip_date, &zip_time);
 632
 633         strbuf_init(&zip_dir, 0);
 634
 635         err = write_archive_entries(args, write_zip_entry);
 636         if (!err)
 637                 write_zip_trailer(args->commit_oid);
 638
 639         strbuf_release(&zip_dir);
 640
 641         return err;
 642 }
 643
 644 static struct archiver zip_archiver = {
 645         .name = "zip",
 646         .write_archive = write_zip_archive,
 647         .flags = ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE,
 648 };
 649
 650 void init_zip_archiver(void)
 651 {
 652         register_archiver(&zip_archiver);
 653 }