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 /* We only care about the "buf" part here. */
  15 static struct strbuf zip_dir;
  16
  17 static uintmax_t zip_offset;
  18 static uint64_t zip_dir_entries;
  19
  20 static unsigned int max_creator_version;
  21
  22 #define ZIP_STREAM      (1 <<  3)
  23 #define ZIP_UTF8        (1 << 11)
  24
  25 struct zip_local_header {
  26         unsigned char magic[4];
  27         unsigned char version[2];
  28         unsigned char flags[2];
  29         unsigned char compression_method[2];
  30         unsigned char mtime[2];
  31         unsigned char mdate[2];
  32         unsigned char crc32[4];
  33         unsigned char compressed_size[4];
  34         unsigned char size[4];
  35         unsigned char filename_length[2];
  36         unsigned char extra_length[2];
  37         unsigned char _end[1];
  38 };
  39
  40 struct zip_data_desc {
  41         unsigned char magic[4];
  42         unsigned char crc32[4];
  43         unsigned char compressed_size[4];
  44         unsigned char size[4];
  45         unsigned char _end[1];
  46 };
  47
  48 struct zip64_data_desc {
  49         unsigned char magic[4];
  50         unsigned char crc32[4];
  51         unsigned char compressed_size[8];
  52         unsigned char size[8];
  53         unsigned char _end[1];
  54 };
  55
  56 struct zip_dir_trailer {
  57         unsigned char magic[4];
  58         unsigned char disk[2];
  59         unsigned char directory_start_disk[2];
  60         unsigned char entries_on_this_disk[2];
  61         unsigned char entries[2];
  62         unsigned char size[4];
  63         unsigned char offset[4];
  64         unsigned char comment_length[2];
  65         unsigned char _end[1];
  66 };
  67
  68 struct zip_extra_mtime {
  69         unsigned char magic[2];
  70         unsigned char extra_size[2];
  71         unsigned char flags[1];
  72         unsigned char mtime[4];
  73         unsigned char _end[1];
  74 };
  75
  76 struct zip64_extra {
  77         unsigned char magic[2];
  78         unsigned char extra_size[2];
  79         unsigned char size[8];
  80         unsigned char compressed_size[8];
  81         unsigned char _end[1];
  82 };
  83
  84 struct zip64_dir_trailer {
  85         unsigned char magic[4];
  86         unsigned char record_size[8];
  87         unsigned char creator_version[2];
  88         unsigned char version[2];
  89         unsigned char disk[4];
  90         unsigned char directory_start_disk[4];
  91         unsigned char entries_on_this_disk[8];
  92         unsigned char entries[8];
  93         unsigned char size[8];
  94         unsigned char offset[8];
  95         unsigned char _end[1];
  96 };
  97
  98 struct zip64_dir_trailer_locator {
  99         unsigned char magic[4];
 100         unsigned char disk[4];
 101         unsigned char offset[8];
 102         unsigned char number_of_disks[4];
 103         unsigned char _end[1];
 104 };
 105
 106 /*
 107  * On ARM, padding is added at the end of the struct, so a simple
 108  * sizeof(struct ...) reports two bytes more than the payload size
 109  * we're interested in.
 110  */
 111 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
 112 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
 113 #define ZIP64_DATA_DESC_SIZE    offsetof(struct zip64_data_desc, _end)
 114 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
 115 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
 116 #define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
 117 #define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 118         (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 119 #define ZIP64_EXTRA_SIZE        offsetof(struct zip64_extra, _end)
 120 #define ZIP64_EXTRA_PAYLOAD_SIZE \
 121         (ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
 122 #define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
 123 #define ZIP64_DIR_TRAILER_RECORD_SIZE \
 124         (ZIP64_DIR_TRAILER_SIZE - \
 125          offsetof(struct zip64_dir_trailer, creator_version))
 126 #define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
 127         offsetof(struct zip64_dir_trailer_locator, _end)
 128
 129 static void copy_le16(unsigned char *dest, unsigned int n)
 130 {
 131         dest[0] = 0xff & n;
 132         dest[1] = 0xff & (n >> 010);
 133 }
 134
 135 static void copy_le32(unsigned char *dest, unsigned int n)
 136 {
 137         dest[0] = 0xff & n;
 138         dest[1] = 0xff & (n >> 010);
 139         dest[2] = 0xff & (n >> 020);
 140         dest[3] = 0xff & (n >> 030);
 141 }
 142
 143 static void copy_le64(unsigned char *dest, uint64_t 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         dest[4] = 0xff & (n >> 040);
 150         dest[5] = 0xff & (n >> 050);
 151         dest[6] = 0xff & (n >> 060);
 152         dest[7] = 0xff & (n >> 070);
 153 }
 154
 155 static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
 156 {
 157         if (n <= max)
 158                 return n;
 159         *clamped = 1;
 160         return max;
 161 }
 162
 163 static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
 164 {
 165         copy_le16(dest, clamp_max(n, 0xffff, clamped));
 166 }
 167
 168 static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
 169 {
 170         copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
 171 }
 172
 173 static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
 174 {
 175         while (size-- > 0) {
 176                 strbuf_addch(sb, n & 0xff);
 177                 n >>= 8;
 178         }
 179         return -!!n;
 180 }
 181
 182 static uint32_t clamp32(uintmax_t n)
 183 {
 184         const uintmax_t max = 0xffffffff;
 185         return (n < max) ? n : max;
 186 }
 187
 188 static void *zlib_deflate_raw(void *data, unsigned long size,
 189                               int compression_level,
 190                               unsigned long *compressed_size)
 191 {
 192         git_zstream stream;
 193         unsigned long maxsize;
 194         void *buffer;
 195         int result;
 196
 197         git_deflate_init_raw(&stream, compression_level);
 198         maxsize = git_deflate_bound(&stream, size);
 199         buffer = xmalloc(maxsize);
 200
 201         stream.next_in = data;
 202         stream.avail_in = size;
 203         stream.next_out = buffer;
 204         stream.avail_out = maxsize;
 205
 206         do {
 207                 result = git_deflate(&stream, Z_FINISH);
 208         } while (result == Z_OK);
 209
 210         if (result != Z_STREAM_END) {
 211                 free(buffer);
 212                 return NULL;
 213         }
 214
 215         git_deflate_end(&stream);
 216         *compressed_size = stream.total_out;
 217
 218         return buffer;
 219 }
 220
 221 static void write_zip_data_desc(unsigned long size,
 222                                 unsigned long compressed_size,
 223                                 unsigned long crc)
 224 {
 225         if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
 226                 struct zip64_data_desc trailer;
 227                 copy_le32(trailer.magic, 0x08074b50);
 228                 copy_le32(trailer.crc32, crc);
 229                 copy_le64(trailer.compressed_size, compressed_size);
 230                 copy_le64(trailer.size, size);
 231                 write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
 232                 zip_offset += ZIP64_DATA_DESC_SIZE;
 233         } else {
 234                 struct zip_data_desc trailer;
 235                 copy_le32(trailer.magic, 0x08074b50);
 236                 copy_le32(trailer.crc32, crc);
 237                 copy_le32(trailer.compressed_size, compressed_size);
 238                 copy_le32(trailer.size, size);
 239                 write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 240                 zip_offset += ZIP_DATA_DESC_SIZE;
 241         }
 242 }
 243
 244 static void set_zip_header_data_desc(struct zip_local_header *header,
 245                                      unsigned long size,
 246                                      unsigned long compressed_size,
 247                                      unsigned long crc)
 248 {
 249         copy_le32(header->crc32, crc);
 250         copy_le32(header->compressed_size, compressed_size);
 251         copy_le32(header->size, size);
 252 }
 253
 254 static int has_only_ascii(const char *s)
 255 {
 256         for (;;) {
 257                 int c = *s++;
 258                 if (c == '\0')
 259                         return 1;
 260                 if (!isascii(c))
 261                         return 0;
 262         }
 263 }
 264
 265 static int entry_is_binary(const char *path, const void *buffer, size_t size)
 266 {
 267         struct userdiff_driver *driver = userdiff_find_by_path(path);
 268         if (!driver)
 269                 driver = userdiff_find_by_name("default");
 270         if (driver->binary != -1)
 271                 return driver->binary;
 272         return buffer_is_binary(buffer, size);
 273 }
 274
 275 #define STREAM_BUFFER_SIZE (1024 * 16)
 276
 277 static int write_zip_entry(struct archiver_args *args,
 278                            const unsigned char *sha1,
 279                            const char *path, size_t pathlen,
 280                            unsigned int mode)
 281 {
 282         struct zip_local_header header;
 283         uintmax_t offset = zip_offset;
 284         struct zip_extra_mtime extra;
 285         struct zip64_extra extra64;
 286         size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
 287         int need_zip64_extra = 0;
 288         unsigned long attr2;
 289         unsigned long compressed_size;
 290         unsigned long crc;
 291         int method;
 292         unsigned char *out;
 293         void *deflated = NULL;
 294         void *buffer;
 295         struct git_istream *stream = NULL;
 296         unsigned long flags = 0;
 297         unsigned long size;
 298         int is_binary = -1;
 299         const char *path_without_prefix = path + args->baselen;
 300         unsigned int creator_version = 0;
 301         unsigned int version_needed = 10;
 302         size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
 303         size_t zip64_dir_extra_payload_size = 0;
 304
 305         crc = crc32(0, NULL, 0);
 306
 307         if (!has_only_ascii(path)) {
 308                 if (is_utf8(path))
 309                         flags |= ZIP_UTF8;
 310                 else
 311                         warning("Path is not valid UTF-8: %s", path);
 312         }
 313
 314         if (pathlen > 0xffff) {
 315                 return error("path too long (%d chars, SHA1: %s): %s",
 316                                 (int)pathlen, sha1_to_hex(sha1), path);
 317         }
 318
 319         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 320                 method = 0;
 321                 attr2 = 16;
 322                 out = NULL;
 323                 size = 0;
 324                 compressed_size = 0;
 325                 buffer = NULL;
 326         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 327                 enum object_type type = sha1_object_info(sha1, &size);
 328
 329                 method = 0;
 330                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 331                         (mode & 0111) ? ((mode) << 16) : 0;
 332                 if (S_ISLNK(mode) || (mode & 0111))
 333                         creator_version = 0x0317;
 334                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 335                         method = 8;
 336
 337                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 338                     size > big_file_threshold) {
 339                         stream = open_istream(sha1, &type, &size, NULL);
 340                         if (!stream)
 341                                 return error("cannot stream blob %s",
 342                                              sha1_to_hex(sha1));
 343                         flags |= ZIP_STREAM;
 344                         out = buffer = NULL;
 345                 } else {
 346                         buffer = sha1_file_to_archive(args, path, sha1, mode,
 347                                                       &type, &size);
 348                         if (!buffer)
 349                                 return error("cannot read %s",
 350                                              sha1_to_hex(sha1));
 351                         crc = crc32(crc, buffer, size);
 352                         is_binary = entry_is_binary(path_without_prefix,
 353                                                     buffer, size);
 354                         out = buffer;
 355                 }
 356                 compressed_size = (method == 0) ? size : 0;
 357         } else {
 358                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 359                                 sha1_to_hex(sha1));
 360         }
 361
 362         if (creator_version > max_creator_version)
 363                 max_creator_version = creator_version;
 364
 365         if (buffer && method == 8) {
 366                 out = deflated = zlib_deflate_raw(buffer, size,
 367                                                   args->compression_level,
 368                                                   &compressed_size);
 369                 if (!out || compressed_size >= size) {
 370                         out = buffer;
 371                         method = 0;
 372                         compressed_size = size;
 373                 }
 374         }
 375
 376         copy_le16(extra.magic, 0x5455);
 377         copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 378         extra.flags[0] = 1;     /* just mtime */
 379         copy_le32(extra.mtime, args->time);
 380
 381         if (size > 0xffffffff || compressed_size > 0xffffffff)
 382                 need_zip64_extra = 1;
 383         if (stream && size > 0x7fffffff)
 384                 need_zip64_extra = 1;
 385
 386         if (need_zip64_extra)
 387                 version_needed = 45;
 388
 389         copy_le32(header.magic, 0x04034b50);
 390         copy_le16(header.version, version_needed);
 391         copy_le16(header.flags, flags);
 392         copy_le16(header.compression_method, method);
 393         copy_le16(header.mtime, zip_time);
 394         copy_le16(header.mdate, zip_date);
 395         if (need_zip64_extra) {
 396                 set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
 397                 header_extra_size += ZIP64_EXTRA_SIZE;
 398         } else {
 399                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 400         }
 401         copy_le16(header.filename_length, pathlen);
 402         copy_le16(header.extra_length, header_extra_size);
 403         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 404         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 405         write_or_die(1, path, pathlen);
 406         zip_offset += pathlen;
 407         write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 408         zip_offset += ZIP_EXTRA_MTIME_SIZE;
 409         if (need_zip64_extra) {
 410                 copy_le16(extra64.magic, 0x0001);
 411                 copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
 412                 copy_le64(extra64.size, size);
 413                 copy_le64(extra64.compressed_size, compressed_size);
 414                 write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
 415                 zip_offset += ZIP64_EXTRA_SIZE;
 416         }
 417
 418         if (stream && method == 0) {
 419                 unsigned char buf[STREAM_BUFFER_SIZE];
 420                 ssize_t readlen;
 421
 422                 for (;;) {
 423                         readlen = read_istream(stream, buf, sizeof(buf));
 424                         if (readlen <= 0)
 425                                 break;
 426                         crc = crc32(crc, buf, readlen);
 427                         if (is_binary == -1)
 428                                 is_binary = entry_is_binary(path_without_prefix,
 429                                                             buf, readlen);
 430                         write_or_die(1, buf, readlen);
 431                 }
 432                 close_istream(stream);
 433                 if (readlen)
 434                         return readlen;
 435
 436                 compressed_size = size;
 437                 zip_offset += compressed_size;
 438
 439                 write_zip_data_desc(size, compressed_size, crc);
 440         } else if (stream && method == 8) {
 441                 unsigned char buf[STREAM_BUFFER_SIZE];
 442                 ssize_t readlen;
 443                 git_zstream zstream;
 444                 int result;
 445                 size_t out_len;
 446                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 447
 448                 git_deflate_init_raw(&zstream, args->compression_level);
 449
 450                 compressed_size = 0;
 451                 zstream.next_out = compressed;
 452                 zstream.avail_out = sizeof(compressed);
 453
 454                 for (;;) {
 455                         readlen = read_istream(stream, buf, sizeof(buf));
 456                         if (readlen <= 0)
 457                                 break;
 458                         crc = crc32(crc, buf, readlen);
 459                         if (is_binary == -1)
 460                                 is_binary = entry_is_binary(path_without_prefix,
 461                                                             buf, readlen);
 462
 463                         zstream.next_in = buf;
 464                         zstream.avail_in = readlen;
 465                         result = git_deflate(&zstream, 0);
 466                         if (result != Z_OK)
 467                                 die("deflate error (%d)", result);
 468                         out_len = zstream.next_out - compressed;
 469
 470                         if (out_len > 0) {
 471                                 write_or_die(1, compressed, out_len);
 472                                 compressed_size += out_len;
 473                                 zstream.next_out = compressed;
 474                                 zstream.avail_out = sizeof(compressed);
 475                         }
 476
 477                 }
 478                 close_istream(stream);
 479                 if (readlen)
 480                         return readlen;
 481
 482                 zstream.next_in = buf;
 483                 zstream.avail_in = 0;
 484                 result = git_deflate(&zstream, Z_FINISH);
 485                 if (result != Z_STREAM_END)
 486                         die("deflate error (%d)", result);
 487
 488                 git_deflate_end(&zstream);
 489                 out_len = zstream.next_out - compressed;
 490                 write_or_die(1, compressed, out_len);
 491                 compressed_size += out_len;
 492                 zip_offset += compressed_size;
 493
 494                 write_zip_data_desc(size, compressed_size, crc);
 495         } else if (compressed_size > 0) {
 496                 write_or_die(1, out, compressed_size);
 497                 zip_offset += compressed_size;
 498         }
 499
 500         free(deflated);
 501         free(buffer);
 502
 503         if (compressed_size > 0xffffffff || size > 0xffffffff ||
 504             offset > 0xffffffff) {
 505                 if (compressed_size >= 0xffffffff)
 506                         zip64_dir_extra_payload_size += 8;
 507                 if (size >= 0xffffffff)
 508                         zip64_dir_extra_payload_size += 8;
 509                 if (offset >= 0xffffffff)
 510                         zip64_dir_extra_payload_size += 8;
 511                 zip_dir_extra_size += 2 + 2 + zip64_dir_extra_payload_size;
 512         }
 513
 514         strbuf_add_le(&zip_dir, 4, 0x02014b50); /* magic */
 515         strbuf_add_le(&zip_dir, 2, creator_version);
 516         strbuf_add_le(&zip_dir, 2, version_needed);
 517         strbuf_add_le(&zip_dir, 2, flags);
 518         strbuf_add_le(&zip_dir, 2, method);
 519         strbuf_add_le(&zip_dir, 2, zip_time);
 520         strbuf_add_le(&zip_dir, 2, zip_date);
 521         strbuf_add_le(&zip_dir, 4, crc);
 522         strbuf_add_le(&zip_dir, 4, clamp32(compressed_size));
 523         strbuf_add_le(&zip_dir, 4, clamp32(size));
 524         strbuf_add_le(&zip_dir, 2, pathlen);
 525         strbuf_add_le(&zip_dir, 2, zip_dir_extra_size);
 526         strbuf_add_le(&zip_dir, 2, 0);          /* comment length */
 527         strbuf_add_le(&zip_dir, 2, 0);          /* disk */
 528         strbuf_add_le(&zip_dir, 2, !is_binary);
 529         strbuf_add_le(&zip_dir, 4, attr2);
 530         strbuf_add_le(&zip_dir, 4, clamp32(offset));
 531         strbuf_add(&zip_dir, path, pathlen);
 532         strbuf_add(&zip_dir, &extra, ZIP_EXTRA_MTIME_SIZE);
 533         if (zip64_dir_extra_payload_size) {
 534                 strbuf_add_le(&zip_dir, 2, 0x0001);     /* magic */
 535                 strbuf_add_le(&zip_dir, 2, zip64_dir_extra_payload_size);
 536                 if (size >= 0xffffffff)
 537                         strbuf_add_le(&zip_dir, 8, size);
 538                 if (compressed_size >= 0xffffffff)
 539                         strbuf_add_le(&zip_dir, 8, compressed_size);
 540                 if (offset >= 0xffffffff)
 541                         strbuf_add_le(&zip_dir, 8, offset);
 542         }
 543         zip_dir_entries++;
 544
 545         return 0;
 546 }
 547
 548 static void write_zip64_trailer(void)
 549 {
 550         struct zip64_dir_trailer trailer64;
 551         struct zip64_dir_trailer_locator locator64;
 552
 553         copy_le32(trailer64.magic, 0x06064b50);
 554         copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
 555         copy_le16(trailer64.creator_version, max_creator_version);
 556         copy_le16(trailer64.version, 45);
 557         copy_le32(trailer64.disk, 0);
 558         copy_le32(trailer64.directory_start_disk, 0);
 559         copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
 560         copy_le64(trailer64.entries, zip_dir_entries);
 561         copy_le64(trailer64.size, zip_dir.len);
 562         copy_le64(trailer64.offset, zip_offset);
 563
 564         copy_le32(locator64.magic, 0x07064b50);
 565         copy_le32(locator64.disk, 0);
 566         copy_le64(locator64.offset, zip_offset + zip_dir.len);
 567         copy_le32(locator64.number_of_disks, 1);
 568
 569         write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
 570         write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
 571 }
 572
 573 static void write_zip_trailer(const unsigned char *sha1)
 574 {
 575         struct zip_dir_trailer trailer;
 576         int clamped = 0;
 577
 578         copy_le32(trailer.magic, 0x06054b50);
 579         copy_le16(trailer.disk, 0);
 580         copy_le16(trailer.directory_start_disk, 0);
 581         copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
 582                         &clamped);
 583         copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
 584         copy_le32(trailer.size, zip_dir.len);
 585         copy_le32_clamp(trailer.offset, zip_offset, &clamped);
 586         copy_le16(trailer.comment_length, sha1 ? GIT_SHA1_HEXSZ : 0);
 587
 588         write_or_die(1, zip_dir.buf, zip_dir.len);
 589         if (clamped)
 590                 write_zip64_trailer();
 591         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 592         if (sha1)
 593                 write_or_die(1, sha1_to_hex(sha1), GIT_SHA1_HEXSZ);
 594 }
 595
 596 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 597 {
 598         struct tm *t = localtime(time);
 599
 600         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 601                     (t->tm_year + 1900 - 1980) * 512;
 602         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 603 }
 604
 605 static int archive_zip_config(const char *var, const char *value, void *data)
 606 {
 607         return userdiff_config(var, value);
 608 }
 609
 610 static int write_zip_archive(const struct archiver *ar,
 611                              struct archiver_args *args)
 612 {
 613         int err;
 614
 615         git_config(archive_zip_config, NULL);
 616
 617         dos_time(&args->time, &zip_date, &zip_time);
 618
 619         strbuf_init(&zip_dir, 0);
 620
 621         err = write_archive_entries(args, write_zip_entry);
 622         if (!err)
 623                 write_zip_trailer(args->commit_sha1);
 624
 625         strbuf_release(&zip_dir);
 626
 627         return err;
 628 }
 629
 630 static struct archiver zip_archiver = {
 631         "zip",
 632         write_zip_archive,
 633         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 634 };
 635
 636 void init_zip_archiver(void)
 637 {
 638         register_archiver(&zip_archiver);
 639 }