archive-zip.c

   1 /*
   2  * Copyright (c) 2006 Rene Scharfe
   3  */
   4 #include "cache.h"
   5 #include "archive.h"
   6 #include "streaming.h"
   7
   8 static int zip_date;
   9 static int zip_time;
  10
  11 static unsigned char *zip_dir;
  12 static unsigned int zip_dir_size;
  13
  14 static unsigned int zip_offset;
  15 static unsigned int zip_dir_offset;
  16 static unsigned int zip_dir_entries;
  17
  18 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  19 #define ZIP_STREAM (8)
  20
  21 struct zip_local_header {
  22         unsigned char magic[4];
  23         unsigned char version[2];
  24         unsigned char flags[2];
  25         unsigned char compression_method[2];
  26         unsigned char mtime[2];
  27         unsigned char mdate[2];
  28         unsigned char crc32[4];
  29         unsigned char compressed_size[4];
  30         unsigned char size[4];
  31         unsigned char filename_length[2];
  32         unsigned char extra_length[2];
  33         unsigned char _end[1];
  34 };
  35
  36 struct zip_data_desc {
  37         unsigned char magic[4];
  38         unsigned char crc32[4];
  39         unsigned char compressed_size[4];
  40         unsigned char size[4];
  41         unsigned char _end[1];
  42 };
  43
  44 struct zip_dir_header {
  45         unsigned char magic[4];
  46         unsigned char creator_version[2];
  47         unsigned char version[2];
  48         unsigned char flags[2];
  49         unsigned char compression_method[2];
  50         unsigned char mtime[2];
  51         unsigned char mdate[2];
  52         unsigned char crc32[4];
  53         unsigned char compressed_size[4];
  54         unsigned char size[4];
  55         unsigned char filename_length[2];
  56         unsigned char extra_length[2];
  57         unsigned char comment_length[2];
  58         unsigned char disk[2];
  59         unsigned char attr1[2];
  60         unsigned char attr2[4];
  61         unsigned char offset[4];
  62         unsigned char _end[1];
  63 };
  64
  65 struct zip_dir_trailer {
  66         unsigned char magic[4];
  67         unsigned char disk[2];
  68         unsigned char directory_start_disk[2];
  69         unsigned char entries_on_this_disk[2];
  70         unsigned char entries[2];
  71         unsigned char size[4];
  72         unsigned char offset[4];
  73         unsigned char comment_length[2];
  74         unsigned char _end[1];
  75 };
  76
  77 /*
  78  * On ARM, padding is added at the end of the struct, so a simple
  79  * sizeof(struct ...) reports two bytes more than the payload size
  80  * we're interested in.
  81  */
  82 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  83 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
  84 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  85 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  86
  87 static void copy_le16(unsigned char *dest, unsigned int n)
  88 {
  89         dest[0] = 0xff & n;
  90         dest[1] = 0xff & (n >> 010);
  91 }
  92
  93 static void copy_le32(unsigned char *dest, unsigned int n)
  94 {
  95         dest[0] = 0xff & n;
  96         dest[1] = 0xff & (n >> 010);
  97         dest[2] = 0xff & (n >> 020);
  98         dest[3] = 0xff & (n >> 030);
  99 }
 100
 101 static void *zlib_deflate(void *data, unsigned long size,
 102                 int compression_level, unsigned long *compressed_size)
 103 {
 104         git_zstream stream;
 105         unsigned long maxsize;
 106         void *buffer;
 107         int result;
 108
 109         memset(&stream, 0, sizeof(stream));
 110         git_deflate_init(&stream, compression_level);
 111         maxsize = git_deflate_bound(&stream, size);
 112         buffer = xmalloc(maxsize);
 113
 114         stream.next_in = data;
 115         stream.avail_in = size;
 116         stream.next_out = buffer;
 117         stream.avail_out = maxsize;
 118
 119         do {
 120                 result = git_deflate(&stream, Z_FINISH);
 121         } while (result == Z_OK);
 122
 123         if (result != Z_STREAM_END) {
 124                 free(buffer);
 125                 return NULL;
 126         }
 127
 128         git_deflate_end(&stream);
 129         *compressed_size = stream.total_out;
 130
 131         return buffer;
 132 }
 133
 134 static void write_zip_data_desc(unsigned long size,
 135                                 unsigned long compressed_size,
 136                                 unsigned long crc)
 137 {
 138         struct zip_data_desc trailer;
 139
 140         copy_le32(trailer.magic, 0x08074b50);
 141         copy_le32(trailer.crc32, crc);
 142         copy_le32(trailer.compressed_size, compressed_size);
 143         copy_le32(trailer.size, size);
 144         write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 145 }
 146
 147 static void set_zip_dir_data_desc(struct zip_dir_header *header,
 148                                   unsigned long size,
 149                                   unsigned long compressed_size,
 150                                   unsigned long crc)
 151 {
 152         copy_le32(header->crc32, crc);
 153         copy_le32(header->compressed_size, compressed_size);
 154         copy_le32(header->size, size);
 155 }
 156
 157 static void set_zip_header_data_desc(struct zip_local_header *header,
 158                                      unsigned long size,
 159                                      unsigned long compressed_size,
 160                                      unsigned long crc)
 161 {
 162         copy_le32(header->crc32, crc);
 163         copy_le32(header->compressed_size, compressed_size);
 164         copy_le32(header->size, size);
 165 }
 166
 167 #define STREAM_BUFFER_SIZE (1024 * 16)
 168
 169 static int write_zip_entry(struct archiver_args *args,
 170                            const unsigned char *sha1,
 171                            const char *path, size_t pathlen,
 172                            unsigned int mode)
 173 {
 174         struct zip_local_header header;
 175         struct zip_dir_header dirent;
 176         unsigned long attr2;
 177         unsigned long compressed_size;
 178         unsigned long crc;
 179         unsigned long direntsize;
 180         int method;
 181         unsigned char *out;
 182         void *deflated = NULL;
 183         void *buffer;
 184         struct git_istream *stream = NULL;
 185         unsigned long flags = 0;
 186         unsigned long size;
 187
 188         crc = crc32(0, NULL, 0);
 189
 190         if (pathlen > 0xffff) {
 191                 return error("path too long (%d chars, SHA1: %s): %s",
 192                                 (int)pathlen, sha1_to_hex(sha1), path);
 193         }
 194
 195         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 196                 method = 0;
 197                 attr2 = 16;
 198                 out = NULL;
 199                 size = 0;
 200                 compressed_size = 0;
 201                 buffer = NULL;
 202                 size = 0;
 203         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 204                 enum object_type type = sha1_object_info(sha1, &size);
 205
 206                 method = 0;
 207                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 208                         (mode & 0111) ? ((mode) << 16) : 0;
 209                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 210                         method = 8;
 211                 compressed_size = size;
 212
 213                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 214                     size > big_file_threshold) {
 215                         stream = open_istream(sha1, &type, &size, NULL);
 216                         if (!stream)
 217                                 return error("cannot stream blob %s",
 218                                              sha1_to_hex(sha1));
 219                         flags |= ZIP_STREAM;
 220                         out = buffer = NULL;
 221                 } else {
 222                         buffer = sha1_file_to_archive(args, path, sha1, mode,
 223                                                       &type, &size);
 224                         if (!buffer)
 225                                 return error("cannot read %s",
 226                                              sha1_to_hex(sha1));
 227                         crc = crc32(crc, buffer, size);
 228                         out = buffer;
 229                 }
 230         } else {
 231                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 232                                 sha1_to_hex(sha1));
 233         }
 234
 235         if (buffer && method == 8) {
 236                 deflated = zlib_deflate(buffer, size, args->compression_level,
 237                                 &compressed_size);
 238                 if (deflated && compressed_size - 6 < size) {
 239                         /* ZLIB --> raw compressed data (see RFC 1950) */
 240                         /* CMF and FLG ... */
 241                         out = (unsigned char *)deflated + 2;
 242                         compressed_size -= 6;   /* ... and ADLER32 */
 243                 } else {
 244                         method = 0;
 245                         compressed_size = size;
 246                 }
 247         }
 248
 249         /* make sure we have enough free space in the dictionary */
 250         direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 251         while (zip_dir_size < zip_dir_offset + direntsize) {
 252                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 253                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 254         }
 255
 256         copy_le32(dirent.magic, 0x02014b50);
 257         copy_le16(dirent.creator_version,
 258                 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 259         copy_le16(dirent.version, 10);
 260         copy_le16(dirent.flags, flags);
 261         copy_le16(dirent.compression_method, method);
 262         copy_le16(dirent.mtime, zip_time);
 263         copy_le16(dirent.mdate, zip_date);
 264         set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 265         copy_le16(dirent.filename_length, pathlen);
 266         copy_le16(dirent.extra_length, 0);
 267         copy_le16(dirent.comment_length, 0);
 268         copy_le16(dirent.disk, 0);
 269         copy_le16(dirent.attr1, 0);
 270         copy_le32(dirent.attr2, attr2);
 271         copy_le32(dirent.offset, zip_offset);
 272
 273         copy_le32(header.magic, 0x04034b50);
 274         copy_le16(header.version, 10);
 275         copy_le16(header.flags, flags);
 276         copy_le16(header.compression_method, method);
 277         copy_le16(header.mtime, zip_time);
 278         copy_le16(header.mdate, zip_date);
 279         if (flags & ZIP_STREAM)
 280                 set_zip_header_data_desc(&header, 0, 0, 0);
 281         else
 282                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 283         copy_le16(header.filename_length, pathlen);
 284         copy_le16(header.extra_length, 0);
 285         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 286         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 287         write_or_die(1, path, pathlen);
 288         zip_offset += pathlen;
 289         if (stream && method == 0) {
 290                 unsigned char buf[STREAM_BUFFER_SIZE];
 291                 ssize_t readlen;
 292
 293                 for (;;) {
 294                         readlen = read_istream(stream, buf, sizeof(buf));
 295                         if (readlen <= 0)
 296                                 break;
 297                         crc = crc32(crc, buf, readlen);
 298                         write_or_die(1, buf, readlen);
 299                 }
 300                 close_istream(stream);
 301                 if (readlen)
 302                         return readlen;
 303
 304                 compressed_size = size;
 305                 zip_offset += compressed_size;
 306
 307                 write_zip_data_desc(size, compressed_size, crc);
 308                 zip_offset += ZIP_DATA_DESC_SIZE;
 309
 310                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 311         } else if (stream && method == 8) {
 312                 unsigned char buf[STREAM_BUFFER_SIZE];
 313                 ssize_t readlen;
 314                 git_zstream zstream;
 315                 int result;
 316                 size_t out_len;
 317                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 318
 319                 memset(&zstream, 0, sizeof(zstream));
 320                 git_deflate_init(&zstream, args->compression_level);
 321
 322                 compressed_size = 0;
 323                 zstream.next_out = compressed;
 324                 zstream.avail_out = sizeof(compressed);
 325
 326                 for (;;) {
 327                         readlen = read_istream(stream, buf, sizeof(buf));
 328                         if (readlen <= 0)
 329                                 break;
 330                         crc = crc32(crc, buf, readlen);
 331
 332                         zstream.next_in = buf;
 333                         zstream.avail_in = readlen;
 334                         result = git_deflate(&zstream, 0);
 335                         if (result != Z_OK)
 336                                 die("deflate error (%d)", result);
 337                         out = compressed;
 338                         if (!compressed_size)
 339                                 out += 2;
 340                         out_len = zstream.next_out - out;
 341
 342                         if (out_len > 0) {
 343                                 write_or_die(1, out, out_len);
 344                                 compressed_size += out_len;
 345                                 zstream.next_out = compressed;
 346                                 zstream.avail_out = sizeof(compressed);
 347                         }
 348
 349                 }
 350                 close_istream(stream);
 351                 if (readlen)
 352                         return readlen;
 353
 354                 zstream.next_in = buf;
 355                 zstream.avail_in = 0;
 356                 result = git_deflate(&zstream, Z_FINISH);
 357                 if (result != Z_STREAM_END)
 358                         die("deflate error (%d)", result);
 359
 360                 git_deflate_end(&zstream);
 361                 out = compressed;
 362                 if (!compressed_size)
 363                         out += 2;
 364                 out_len = zstream.next_out - out - 4;
 365                 write_or_die(1, out, out_len);
 366                 compressed_size += out_len;
 367                 zip_offset += compressed_size;
 368
 369                 write_zip_data_desc(size, compressed_size, crc);
 370                 zip_offset += ZIP_DATA_DESC_SIZE;
 371
 372                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 373         } else if (compressed_size > 0) {
 374                 write_or_die(1, out, compressed_size);
 375                 zip_offset += compressed_size;
 376         }
 377
 378         free(deflated);
 379         free(buffer);
 380
 381         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 382         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 383         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 384         zip_dir_offset += pathlen;
 385         zip_dir_entries++;
 386
 387         return 0;
 388 }
 389
 390 static void write_zip_trailer(const unsigned char *sha1)
 391 {
 392         struct zip_dir_trailer trailer;
 393
 394         copy_le32(trailer.magic, 0x06054b50);
 395         copy_le16(trailer.disk, 0);
 396         copy_le16(trailer.directory_start_disk, 0);
 397         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 398         copy_le16(trailer.entries, zip_dir_entries);
 399         copy_le32(trailer.size, zip_dir_offset);
 400         copy_le32(trailer.offset, zip_offset);
 401         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 402
 403         write_or_die(1, zip_dir, zip_dir_offset);
 404         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 405         if (sha1)
 406                 write_or_die(1, sha1_to_hex(sha1), 40);
 407 }
 408
 409 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 410 {
 411         struct tm *t = localtime(time);
 412
 413         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 414                     (t->tm_year + 1900 - 1980) * 512;
 415         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 416 }
 417
 418 static int write_zip_archive(const struct archiver *ar,
 419                              struct archiver_args *args)
 420 {
 421         int err;
 422
 423         dos_time(&args->time, &zip_date, &zip_time);
 424
 425         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 426         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 427
 428         err = write_archive_entries(args, write_zip_entry);
 429         if (!err)
 430                 write_zip_trailer(args->commit_sha1);
 431
 432         free(zip_dir);
 433
 434         return err;
 435 }
 436
 437 static struct archiver zip_archiver = {
 438         "zip",
 439         write_zip_archive,
 440         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 441 };
 442
 443 void init_zip_archiver(void)
 444 {
 445         register_archiver(&zip_archiver);
 446 }