archive-zip.con commit t6041: do not compress backup tar file (f5ee54a)
   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
  11static int zip_date;
  12static int zip_time;
  13
  14static unsigned char *zip_dir;
  15static unsigned int zip_dir_size;
  16
  17static unsigned int zip_offset;
  18static unsigned int zip_dir_offset;
  19static unsigned int zip_dir_entries;
  20
  21#define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  22#define ZIP_STREAM      (1 <<  3)
  23#define ZIP_UTF8        (1 << 11)
  24
  25struct 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
  40struct 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
  48struct zip_dir_header {
  49        unsigned char magic[4];
  50        unsigned char creator_version[2];
  51        unsigned char version[2];
  52        unsigned char flags[2];
  53        unsigned char compression_method[2];
  54        unsigned char mtime[2];
  55        unsigned char mdate[2];
  56        unsigned char crc32[4];
  57        unsigned char compressed_size[4];
  58        unsigned char size[4];
  59        unsigned char filename_length[2];
  60        unsigned char extra_length[2];
  61        unsigned char comment_length[2];
  62        unsigned char disk[2];
  63        unsigned char attr1[2];
  64        unsigned char attr2[4];
  65        unsigned char offset[4];
  66        unsigned char _end[1];
  67};
  68
  69struct zip_dir_trailer {
  70        unsigned char magic[4];
  71        unsigned char disk[2];
  72        unsigned char directory_start_disk[2];
  73        unsigned char entries_on_this_disk[2];
  74        unsigned char entries[2];
  75        unsigned char size[4];
  76        unsigned char offset[4];
  77        unsigned char comment_length[2];
  78        unsigned char _end[1];
  79};
  80
  81struct zip_extra_mtime {
  82        unsigned char magic[2];
  83        unsigned char extra_size[2];
  84        unsigned char flags[1];
  85        unsigned char mtime[4];
  86        unsigned char _end[1];
  87};
  88
  89/*
  90 * On ARM, padding is added at the end of the struct, so a simple
  91 * sizeof(struct ...) reports two bytes more than the payload size
  92 * we're interested in.
  93 */
  94#define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  95#define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
  96#define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  97#define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  98#define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
  99#define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
 100        (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
 101
 102static void copy_le16(unsigned char *dest, unsigned int n)
 103{
 104        dest[0] = 0xff & n;
 105        dest[1] = 0xff & (n >> 010);
 106}
 107
 108static void copy_le32(unsigned char *dest, unsigned int n)
 109{
 110        dest[0] = 0xff & n;
 111        dest[1] = 0xff & (n >> 010);
 112        dest[2] = 0xff & (n >> 020);
 113        dest[3] = 0xff & (n >> 030);
 114}
 115
 116static void *zlib_deflate_raw(void *data, unsigned long size,
 117                              int compression_level,
 118                              unsigned long *compressed_size)
 119{
 120        git_zstream stream;
 121        unsigned long maxsize;
 122        void *buffer;
 123        int result;
 124
 125        git_deflate_init_raw(&stream, compression_level);
 126        maxsize = git_deflate_bound(&stream, size);
 127        buffer = xmalloc(maxsize);
 128
 129        stream.next_in = data;
 130        stream.avail_in = size;
 131        stream.next_out = buffer;
 132        stream.avail_out = maxsize;
 133
 134        do {
 135                result = git_deflate(&stream, Z_FINISH);
 136        } while (result == Z_OK);
 137
 138        if (result != Z_STREAM_END) {
 139                free(buffer);
 140                return NULL;
 141        }
 142
 143        git_deflate_end(&stream);
 144        *compressed_size = stream.total_out;
 145
 146        return buffer;
 147}
 148
 149static void write_zip_data_desc(unsigned long size,
 150                                unsigned long compressed_size,
 151                                unsigned long crc)
 152{
 153        struct zip_data_desc trailer;
 154
 155        copy_le32(trailer.magic, 0x08074b50);
 156        copy_le32(trailer.crc32, crc);
 157        copy_le32(trailer.compressed_size, compressed_size);
 158        copy_le32(trailer.size, size);
 159        write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 160}
 161
 162static void set_zip_dir_data_desc(struct zip_dir_header *header,
 163                                  unsigned long size,
 164                                  unsigned long compressed_size,
 165                                  unsigned long crc)
 166{
 167        copy_le32(header->crc32, crc);
 168        copy_le32(header->compressed_size, compressed_size);
 169        copy_le32(header->size, size);
 170}
 171
 172static void set_zip_header_data_desc(struct zip_local_header *header,
 173                                     unsigned long size,
 174                                     unsigned long compressed_size,
 175                                     unsigned long crc)
 176{
 177        copy_le32(header->crc32, crc);
 178        copy_le32(header->compressed_size, compressed_size);
 179        copy_le32(header->size, size);
 180}
 181
 182static int has_only_ascii(const char *s)
 183{
 184        for (;;) {
 185                int c = *s++;
 186                if (c == '\0')
 187                        return 1;
 188                if (!isascii(c))
 189                        return 0;
 190        }
 191}
 192
 193static int entry_is_binary(const char *path, const void *buffer, size_t size)
 194{
 195        struct userdiff_driver *driver = userdiff_find_by_path(path);
 196        if (!driver)
 197                driver = userdiff_find_by_name("default");
 198        if (driver->binary != -1)
 199                return driver->binary;
 200        return buffer_is_binary(buffer, size);
 201}
 202
 203#define STREAM_BUFFER_SIZE (1024 * 16)
 204
 205static int write_zip_entry(struct archiver_args *args,
 206                           const unsigned char *sha1,
 207                           const char *path, size_t pathlen,
 208                           unsigned int mode)
 209{
 210        struct zip_local_header header;
 211        struct zip_dir_header dirent;
 212        struct zip_extra_mtime extra;
 213        unsigned long attr2;
 214        unsigned long compressed_size;
 215        unsigned long crc;
 216        unsigned long direntsize;
 217        int method;
 218        unsigned char *out;
 219        void *deflated = NULL;
 220        void *buffer;
 221        struct git_istream *stream = NULL;
 222        unsigned long flags = 0;
 223        unsigned long size;
 224        int is_binary = -1;
 225        const char *path_without_prefix = path + args->baselen;
 226
 227        crc = crc32(0, NULL, 0);
 228
 229        if (!has_only_ascii(path)) {
 230                if (is_utf8(path))
 231                        flags |= ZIP_UTF8;
 232                else
 233                        warning("Path is not valid UTF-8: %s", path);
 234        }
 235
 236        if (pathlen > 0xffff) {
 237                return error("path too long (%d chars, SHA1: %s): %s",
 238                                (int)pathlen, sha1_to_hex(sha1), path);
 239        }
 240
 241        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 242                method = 0;
 243                attr2 = 16;
 244                out = NULL;
 245                size = 0;
 246                compressed_size = 0;
 247                buffer = NULL;
 248        } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 249                enum object_type type = sha1_object_info(sha1, &size);
 250
 251                method = 0;
 252                attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 253                        (mode & 0111) ? ((mode) << 16) : 0;
 254                if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 255                        method = 8;
 256
 257                if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 258                    size > big_file_threshold) {
 259                        stream = open_istream(sha1, &type, &size, NULL);
 260                        if (!stream)
 261                                return error("cannot stream blob %s",
 262                                             sha1_to_hex(sha1));
 263                        flags |= ZIP_STREAM;
 264                        out = buffer = NULL;
 265                } else {
 266                        buffer = sha1_file_to_archive(args, path, sha1, mode,
 267                                                      &type, &size);
 268                        if (!buffer)
 269                                return error("cannot read %s",
 270                                             sha1_to_hex(sha1));
 271                        crc = crc32(crc, buffer, size);
 272                        is_binary = entry_is_binary(path_without_prefix,
 273                                                    buffer, size);
 274                        out = buffer;
 275                }
 276                compressed_size = (method == 0) ? size : 0;
 277        } else {
 278                return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 279                                sha1_to_hex(sha1));
 280        }
 281
 282        if (buffer && method == 8) {
 283                out = deflated = zlib_deflate_raw(buffer, size,
 284                                                  args->compression_level,
 285                                                  &compressed_size);
 286                if (!out || compressed_size >= size) {
 287                        out = buffer;
 288                        method = 0;
 289                        compressed_size = size;
 290                }
 291        }
 292
 293        copy_le16(extra.magic, 0x5455);
 294        copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 295        extra.flags[0] = 1;     /* just mtime */
 296        copy_le32(extra.mtime, args->time);
 297
 298        /* make sure we have enough free space in the dictionary */
 299        direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
 300        while (zip_dir_size < zip_dir_offset + direntsize) {
 301                zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 302                zip_dir = xrealloc(zip_dir, zip_dir_size);
 303        }
 304
 305        copy_le32(dirent.magic, 0x02014b50);
 306        copy_le16(dirent.creator_version,
 307                S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 308        copy_le16(dirent.version, 10);
 309        copy_le16(dirent.flags, flags);
 310        copy_le16(dirent.compression_method, method);
 311        copy_le16(dirent.mtime, zip_time);
 312        copy_le16(dirent.mdate, zip_date);
 313        set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 314        copy_le16(dirent.filename_length, pathlen);
 315        copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
 316        copy_le16(dirent.comment_length, 0);
 317        copy_le16(dirent.disk, 0);
 318        copy_le32(dirent.attr2, attr2);
 319        copy_le32(dirent.offset, zip_offset);
 320
 321        copy_le32(header.magic, 0x04034b50);
 322        copy_le16(header.version, 10);
 323        copy_le16(header.flags, flags);
 324        copy_le16(header.compression_method, method);
 325        copy_le16(header.mtime, zip_time);
 326        copy_le16(header.mdate, zip_date);
 327        set_zip_header_data_desc(&header, size, compressed_size, crc);
 328        copy_le16(header.filename_length, pathlen);
 329        copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
 330        write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 331        zip_offset += ZIP_LOCAL_HEADER_SIZE;
 332        write_or_die(1, path, pathlen);
 333        zip_offset += pathlen;
 334        write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 335        zip_offset += ZIP_EXTRA_MTIME_SIZE;
 336        if (stream && method == 0) {
 337                unsigned char buf[STREAM_BUFFER_SIZE];
 338                ssize_t readlen;
 339
 340                for (;;) {
 341                        readlen = read_istream(stream, buf, sizeof(buf));
 342                        if (readlen <= 0)
 343                                break;
 344                        crc = crc32(crc, buf, readlen);
 345                        if (is_binary == -1)
 346                                is_binary = entry_is_binary(path_without_prefix,
 347                                                            buf, readlen);
 348                        write_or_die(1, buf, readlen);
 349                }
 350                close_istream(stream);
 351                if (readlen)
 352                        return readlen;
 353
 354                compressed_size = size;
 355                zip_offset += compressed_size;
 356
 357                write_zip_data_desc(size, compressed_size, crc);
 358                zip_offset += ZIP_DATA_DESC_SIZE;
 359
 360                set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 361        } else if (stream && method == 8) {
 362                unsigned char buf[STREAM_BUFFER_SIZE];
 363                ssize_t readlen;
 364                git_zstream zstream;
 365                int result;
 366                size_t out_len;
 367                unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 368
 369                git_deflate_init_raw(&zstream, args->compression_level);
 370
 371                compressed_size = 0;
 372                zstream.next_out = compressed;
 373                zstream.avail_out = sizeof(compressed);
 374
 375                for (;;) {
 376                        readlen = read_istream(stream, buf, sizeof(buf));
 377                        if (readlen <= 0)
 378                                break;
 379                        crc = crc32(crc, buf, readlen);
 380                        if (is_binary == -1)
 381                                is_binary = entry_is_binary(path_without_prefix,
 382                                                            buf, readlen);
 383
 384                        zstream.next_in = buf;
 385                        zstream.avail_in = readlen;
 386                        result = git_deflate(&zstream, 0);
 387                        if (result != Z_OK)
 388                                die("deflate error (%d)", result);
 389                        out_len = zstream.next_out - compressed;
 390
 391                        if (out_len > 0) {
 392                                write_or_die(1, compressed, out_len);
 393                                compressed_size += out_len;
 394                                zstream.next_out = compressed;
 395                                zstream.avail_out = sizeof(compressed);
 396                        }
 397
 398                }
 399                close_istream(stream);
 400                if (readlen)
 401                        return readlen;
 402
 403                zstream.next_in = buf;
 404                zstream.avail_in = 0;
 405                result = git_deflate(&zstream, Z_FINISH);
 406                if (result != Z_STREAM_END)
 407                        die("deflate error (%d)", result);
 408
 409                git_deflate_end(&zstream);
 410                out_len = zstream.next_out - compressed;
 411                write_or_die(1, compressed, out_len);
 412                compressed_size += out_len;
 413                zip_offset += compressed_size;
 414
 415                write_zip_data_desc(size, compressed_size, crc);
 416                zip_offset += ZIP_DATA_DESC_SIZE;
 417
 418                set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 419        } else if (compressed_size > 0) {
 420                write_or_die(1, out, compressed_size);
 421                zip_offset += compressed_size;
 422        }
 423
 424        free(deflated);
 425        free(buffer);
 426
 427        copy_le16(dirent.attr1, !is_binary);
 428
 429        memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 430        zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 431        memcpy(zip_dir + zip_dir_offset, path, pathlen);
 432        zip_dir_offset += pathlen;
 433        memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
 434        zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
 435        zip_dir_entries++;
 436
 437        return 0;
 438}
 439
 440static void write_zip_trailer(const unsigned char *sha1)
 441{
 442        struct zip_dir_trailer trailer;
 443
 444        copy_le32(trailer.magic, 0x06054b50);
 445        copy_le16(trailer.disk, 0);
 446        copy_le16(trailer.directory_start_disk, 0);
 447        copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 448        copy_le16(trailer.entries, zip_dir_entries);
 449        copy_le32(trailer.size, zip_dir_offset);
 450        copy_le32(trailer.offset, zip_offset);
 451        copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 452
 453        write_or_die(1, zip_dir, zip_dir_offset);
 454        write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 455        if (sha1)
 456                write_or_die(1, sha1_to_hex(sha1), 40);
 457}
 458
 459static void dos_time(time_t *time, int *dos_date, int *dos_time)
 460{
 461        struct tm *t = localtime(time);
 462
 463        *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 464                    (t->tm_year + 1900 - 1980) * 512;
 465        *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 466}
 467
 468static int write_zip_archive(const struct archiver *ar,
 469                             struct archiver_args *args)
 470{
 471        int err;
 472
 473        dos_time(&args->time, &zip_date, &zip_time);
 474
 475        zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 476        zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 477
 478        err = write_archive_entries(args, write_zip_entry);
 479        if (!err)
 480                write_zip_trailer(args->commit_sha1);
 481
 482        free(zip_dir);
 483
 484        return err;
 485}
 486
 487static struct archiver zip_archiver = {
 488        "zip",
 489        write_zip_archive,
 490        ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 491};
 492
 493void init_zip_archiver(void)
 494{
 495        register_archiver(&zip_archiver);
 496}