Andrew's git / gitweb.git / archive-zip.c
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archive-zip.con commit Merge branch 'ma/unpack-trees-free-msgs' (e47dbec)
   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 "userdiff.h"
  10#include "xdiff-interface.h"
  11
  12static int zip_date;
  13static int zip_time;
  14
  15/* We only care about the "buf" part here. */
  16static struct strbuf zip_dir;
  17
  18static uintmax_t zip_offset;
  19static uint64_t zip_dir_entries;
  20
  21static unsigned int max_creator_version;
  22
  23#define ZIP_STREAM      (1 <<  3)
  24#define ZIP_UTF8        (1 << 11)
  25
  26struct zip_local_header {
  27        unsigned char magic[4];
  28        unsigned char version[2];
  29        unsigned char flags[2];
  30        unsigned char compression_method[2];
  31        unsigned char mtime[2];
  32        unsigned char mdate[2];
  33        unsigned char crc32[4];
  34        unsigned char compressed_size[4];
  35        unsigned char size[4];
  36        unsigned char filename_length[2];
  37        unsigned char extra_length[2];
  38        unsigned char _end[1];
  39};
  40
  41struct zip_data_desc {
  42        unsigned char magic[4];
  43        unsigned char crc32[4];
  44        unsigned char compressed_size[4];
  45        unsigned char size[4];
  46        unsigned char _end[1];
  47};
  48
  49struct zip64_data_desc {
  50        unsigned char magic[4];
  51        unsigned char crc32[4];
  52        unsigned char compressed_size[8];
  53        unsigned char size[8];
  54        unsigned char _end[1];
  55};
  56
  57struct zip_dir_trailer {
  58        unsigned char magic[4];
  59        unsigned char disk[2];
  60        unsigned char directory_start_disk[2];
  61        unsigned char entries_on_this_disk[2];
  62        unsigned char entries[2];
  63        unsigned char size[4];
  64        unsigned char offset[4];
  65        unsigned char comment_length[2];
  66        unsigned char _end[1];
  67};
  68
  69struct zip_extra_mtime {
  70        unsigned char magic[2];
  71        unsigned char extra_size[2];
  72        unsigned char flags[1];
  73        unsigned char mtime[4];
  74        unsigned char _end[1];
  75};
  76
  77struct zip64_extra {
  78        unsigned char magic[2];
  79        unsigned char extra_size[2];
  80        unsigned char size[8];
  81        unsigned char compressed_size[8];
  82        unsigned char _end[1];
  83};
  84
  85struct zip64_dir_trailer {
  86        unsigned char magic[4];
  87        unsigned char record_size[8];
  88        unsigned char creator_version[2];
  89        unsigned char version[2];
  90        unsigned char disk[4];
  91        unsigned char directory_start_disk[4];
  92        unsigned char entries_on_this_disk[8];
  93        unsigned char entries[8];
  94        unsigned char size[8];
  95        unsigned char offset[8];
  96        unsigned char _end[1];
  97};
  98
  99struct zip64_dir_trailer_locator {
 100        unsigned char magic[4];
 101        unsigned char disk[4];
 102        unsigned char offset[8];
 103        unsigned char number_of_disks[4];
 104        unsigned char _end[1];
 105};
 106
 107/*
 108 * On ARM, padding is added at the end of the struct, so a simple
 109 * sizeof(struct ...) reports two bytes more than the payload size
 110 * we're interested in.
 111 */
 112#define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
 113#define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
 114#define ZIP64_DATA_DESC_SIZE    offsetof(struct zip64_data_desc, _end)
 115#define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
 116#define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
 117#define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
 118#define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 119        (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 120#define ZIP64_EXTRA_SIZE        offsetof(struct zip64_extra, _end)
 121#define ZIP64_EXTRA_PAYLOAD_SIZE \
 122        (ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
 123#define ZIP64_DIR_TRAILER_SIZE  offsetof(struct zip64_dir_trailer, _end)
 124#define ZIP64_DIR_TRAILER_RECORD_SIZE \
 125        (ZIP64_DIR_TRAILER_SIZE - \
 126         offsetof(struct zip64_dir_trailer, creator_version))
 127#define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
 128        offsetof(struct zip64_dir_trailer_locator, _end)
 129
 130static void copy_le16(unsigned char *dest, unsigned int n)
 131{
 132        dest[0] = 0xff & n;
 133        dest[1] = 0xff & (n >> 010);
 134}
 135
 136static void copy_le32(unsigned char *dest, unsigned int n)
 137{
 138        dest[0] = 0xff & n;
 139        dest[1] = 0xff & (n >> 010);
 140        dest[2] = 0xff & (n >> 020);
 141        dest[3] = 0xff & (n >> 030);
 142}
 143
 144static void copy_le64(unsigned char *dest, uint64_t n)
 145{
 146        dest[0] = 0xff & n;
 147        dest[1] = 0xff & (n >> 010);
 148        dest[2] = 0xff & (n >> 020);
 149        dest[3] = 0xff & (n >> 030);
 150        dest[4] = 0xff & (n >> 040);
 151        dest[5] = 0xff & (n >> 050);
 152        dest[6] = 0xff & (n >> 060);
 153        dest[7] = 0xff & (n >> 070);
 154}
 155
 156static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
 157{
 158        if (n <= max)
 159                return n;
 160        *clamped = 1;
 161        return max;
 162}
 163
 164static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
 165{
 166        copy_le16(dest, clamp_max(n, 0xffff, clamped));
 167}
 168
 169static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
 170{
 171        copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
 172}
 173
 174static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
 175{
 176        while (size-- > 0) {
 177                strbuf_addch(sb, n & 0xff);
 178                n >>= 8;
 179        }
 180        return -!!n;
 181}
 182
 183static uint32_t clamp32(uintmax_t n)
 184{
 185        const uintmax_t max = 0xffffffff;
 186        return (n < max) ? n : max;
 187}
 188
 189static void *zlib_deflate_raw(void *data, unsigned long size,
 190                              int compression_level,
 191                              unsigned long *compressed_size)
 192{
 193        git_zstream stream;
 194        unsigned long maxsize;
 195        void *buffer;
 196        int result;
 197
 198        git_deflate_init_raw(&stream, compression_level);
 199        maxsize = git_deflate_bound(&stream, size);
 200        buffer = xmalloc(maxsize);
 201
 202        stream.next_in = data;
 203        stream.avail_in = size;
 204        stream.next_out = buffer;
 205        stream.avail_out = maxsize;
 206
 207        do {
 208                result = git_deflate(&stream, Z_FINISH);
 209        } while (result == Z_OK);
 210
 211        if (result != Z_STREAM_END) {
 212                free(buffer);
 213                return NULL;
 214        }
 215
 216        git_deflate_end(&stream);
 217        *compressed_size = stream.total_out;
 218
 219        return buffer;
 220}
 221
 222static void write_zip_data_desc(unsigned long size,
 223                                unsigned long compressed_size,
 224                                unsigned long crc)
 225{
 226        if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
 227                struct zip64_data_desc trailer;
 228                copy_le32(trailer.magic, 0x08074b50);
 229                copy_le32(trailer.crc32, crc);
 230                copy_le64(trailer.compressed_size, compressed_size);
 231                copy_le64(trailer.size, size);
 232                write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
 233                zip_offset += ZIP64_DATA_DESC_SIZE;
 234        } else {
 235                struct zip_data_desc trailer;
 236                copy_le32(trailer.magic, 0x08074b50);
 237                copy_le32(trailer.crc32, crc);
 238                copy_le32(trailer.compressed_size, compressed_size);
 239                copy_le32(trailer.size, size);
 240                write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 241                zip_offset += ZIP_DATA_DESC_SIZE;
 242        }
 243}
 244
 245static void set_zip_header_data_desc(struct zip_local_header *header,
 246                                     unsigned long size,
 247                                     unsigned long compressed_size,
 248                                     unsigned long crc)
 249{
 250        copy_le32(header->crc32, crc);
 251        copy_le32(header->compressed_size, compressed_size);
 252        copy_le32(header->size, size);
 253}
 254
 255static int has_only_ascii(const char *s)
 256{
 257        for (;;) {
 258                int c = *s++;
 259                if (c == '\0')
 260                        return 1;
 261                if (!isascii(c))
 262                        return 0;
 263        }
 264}
 265
 266static int entry_is_binary(const char *path, const void *buffer, size_t size)
 267{
 268        struct userdiff_driver *driver = userdiff_find_by_path(path);
 269        if (!driver)
 270                driver = userdiff_find_by_name("default");
 271        if (driver->binary != -1)
 272                return driver->binary;
 273        return buffer_is_binary(buffer, size);
 274}
 275
 276#define STREAM_BUFFER_SIZE (1024 * 16)
 277
 278static int write_zip_entry(struct archiver_args *args,
 279                           const struct object_id *oid,
 280                           const char *path, size_t pathlen,
 281                           unsigned int mode)
 282{
 283        struct zip_local_header header;
 284        uintmax_t offset = zip_offset;
 285        struct zip_extra_mtime extra;
 286        struct zip64_extra extra64;
 287        size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
 288        int need_zip64_extra = 0;
 289        unsigned long attr2;
 290        unsigned long compressed_size;
 291        unsigned long crc;
 292        int method;
 293        unsigned char *out;
 294        void *deflated = NULL;
 295        void *buffer;
 296        struct git_istream *stream = NULL;
 297        unsigned long flags = 0;
 298        unsigned long size;
 299        int is_binary = -1;
 300        const char *path_without_prefix = path + args->baselen;
 301        unsigned int creator_version = 0;
 302        unsigned int version_needed = 10;
 303        size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
 304        size_t zip64_dir_extra_payload_size = 0;
 305
 306        crc = crc32(0, NULL, 0);
 307
 308        if (!has_only_ascii(path)) {
 309                if (is_utf8(path))
 310                        flags |= ZIP_UTF8;
 311                else
 312                        warning("Path is not valid UTF-8: %s", path);
 313        }
 314
 315        if (pathlen > 0xffff) {
 316                return error("path too long (%d chars, SHA1: %s): %s",
 317                                (int)pathlen, oid_to_hex(oid), path);
 318        }
 319
 320        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 321                method = 0;
 322                attr2 = 16;
 323                out = NULL;
 324                size = 0;
 325                compressed_size = 0;
 326                buffer = NULL;
 327        } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 328                enum object_type type = oid_object_info(the_repository, oid,
 329                                                        &size);
 330
 331                method = 0;
 332                attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 333                        (mode & 0111) ? ((mode) << 16) : 0;
 334                if (S_ISLNK(mode) || (mode & 0111))
 335                        creator_version = 0x0317;
 336                if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 337                        method = 8;
 338
 339                if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 340                    size > big_file_threshold) {
 341                        stream = open_istream(oid, &type, &size, NULL);
 342                        if (!stream)
 343                                return error("cannot stream blob %s",
 344                                             oid_to_hex(oid));
 345                        flags |= ZIP_STREAM;
 346                        out = buffer = NULL;
 347                } else {
 348                        buffer = object_file_to_archive(args, path, oid, mode,
 349                                                        &type, &size);
 350                        if (!buffer)
 351                                return error("cannot read %s",
 352                                             oid_to_hex(oid));
 353                        crc = crc32(crc, buffer, size);
 354                        is_binary = entry_is_binary(path_without_prefix,
 355                                                    buffer, size);
 356                        out = buffer;
 357                }
 358                compressed_size = (method == 0) ? size : 0;
 359        } else {
 360                return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 361                                oid_to_hex(oid));
 362        }
 363
 364        if (creator_version > max_creator_version)
 365                max_creator_version = creator_version;
 366
 367        if (buffer && method == 8) {
 368                out = deflated = zlib_deflate_raw(buffer, size,
 369                                                  args->compression_level,
 370                                                  &compressed_size);
 371                if (!out || compressed_size >= size) {
 372                        out = buffer;
 373                        method = 0;
 374                        compressed_size = size;
 375                }
 376        }
 377
 378        copy_le16(extra.magic, 0x5455);
 379        copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 380        extra.flags[0] = 1;     /* just mtime */
 381        copy_le32(extra.mtime, args->time);
 382
 383        if (size > 0xffffffff || compressed_size > 0xffffffff)
 384                need_zip64_extra = 1;
 385        if (stream && size > 0x7fffffff)
 386                need_zip64_extra = 1;
 387
 388        if (need_zip64_extra)
 389                version_needed = 45;
 390
 391        copy_le32(header.magic, 0x04034b50);
 392        copy_le16(header.version, version_needed);
 393        copy_le16(header.flags, flags);
 394        copy_le16(header.compression_method, method);
 395        copy_le16(header.mtime, zip_time);
 396        copy_le16(header.mdate, zip_date);
 397        if (need_zip64_extra) {
 398                set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
 399                header_extra_size += ZIP64_EXTRA_SIZE;
 400        } else {
 401                set_zip_header_data_desc(&header, size, compressed_size, crc);
 402        }
 403        copy_le16(header.filename_length, pathlen);
 404        copy_le16(header.extra_length, header_extra_size);
 405        write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 406        zip_offset += ZIP_LOCAL_HEADER_SIZE;
 407        write_or_die(1, path, pathlen);
 408        zip_offset += pathlen;
 409        write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 410        zip_offset += ZIP_EXTRA_MTIME_SIZE;
 411        if (need_zip64_extra) {
 412                copy_le16(extra64.magic, 0x0001);
 413                copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
 414                copy_le64(extra64.size, size);
 415                copy_le64(extra64.compressed_size, compressed_size);
 416                write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
 417                zip_offset += ZIP64_EXTRA_SIZE;
 418        }
 419
 420        if (stream && method == 0) {
 421                unsigned char buf[STREAM_BUFFER_SIZE];
 422                ssize_t readlen;
 423
 424                for (;;) {
 425                        readlen = read_istream(stream, buf, sizeof(buf));
 426                        if (readlen <= 0)
 427                                break;
 428                        crc = crc32(crc, buf, readlen);
 429                        if (is_binary == -1)
 430                                is_binary = entry_is_binary(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 == 8) {
 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(path_without_prefix,
 463                                                            buf, readlen);
 464
 465                        zstream.next_in = buf;
 466                        zstream.avail_in = readlen;
 467                        result = git_deflate(&zstream, 0);
 468                        if (result != Z_OK)
 469                                die("deflate error (%d)", result);
 470                        out_len = zstream.next_out - compressed;
 471
 472                        if (out_len > 0) {
 473                                write_or_die(1, compressed, out_len);
 474                                compressed_size += out_len;
 475                                zstream.next_out = compressed;
 476                                zstream.avail_out = sizeof(compressed);
 477                        }
 478
 479                }
 480                close_istream(stream);
 481                if (readlen)
 482                        return readlen;
 483
 484                zstream.next_in = buf;
 485                zstream.avail_in = 0;
 486                result = git_deflate(&zstream, Z_FINISH);
 487                if (result != Z_STREAM_END)
 488                        die("deflate error (%d)", result);
 489
 490                git_deflate_end(&zstream);
 491                out_len = zstream.next_out - compressed;
 492                write_or_die(1, compressed, out_len);
 493                compressed_size += out_len;
 494                zip_offset += compressed_size;
 495
 496                write_zip_data_desc(size, compressed_size, crc);
 497        } else if (compressed_size > 0) {
 498                write_or_die(1, out, compressed_size);
 499                zip_offset += compressed_size;
 500        }
 501
 502        free(deflated);
 503        free(buffer);
 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
 550static 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
 575static void write_zip_trailer(const unsigned char *sha1)
 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, sha1 ? GIT_SHA1_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 (sha1)
 595                write_or_die(1, sha1_to_hex(sha1), GIT_SHA1_HEXSZ);
 596}
 597
 598static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
 599{
 600        time_t time;
 601        struct tm *t;
 602
 603        if (date_overflows(*timestamp))
 604                die("timestamp too large for this system: %"PRItime,
 605                    *timestamp);
 606        time = (time_t)*timestamp;
 607        t = localtime(&time);
 608        *timestamp = time;
 609
 610        *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 611                    (t->tm_year + 1900 - 1980) * 512;
 612        *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 613}
 614
 615static int archive_zip_config(const char *var, const char *value, void *data)
 616{
 617        return userdiff_config(var, value);
 618}
 619
 620static 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_sha1);
 634
 635        strbuf_release(&zip_dir);
 636
 637        return err;
 638}
 639
 640static struct archiver zip_archiver = {
 641        "zip",
 642        write_zip_archive,
 643        ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 644};
 645
 646void init_zip_archiver(void)
 647{
 648        register_archiver(&zip_archiver);
 649}