git.oblomov.eu Git - git/blob - 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
   9 static int zip_date;
  10 static int zip_time;
  11
  12 static unsigned char *zip_dir;
  13 static unsigned int zip_dir_size;
  14
  15 static unsigned int zip_offset;
  16 static unsigned int zip_dir_offset;
  17 static unsigned int zip_dir_entries;
  18
  19 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  20 #define ZIP_STREAM      (1 <<  3)
  21 #define ZIP_UTF8        (1 << 11)
  22
  23 struct zip_local_header {
  24         unsigned char magic[4];
  25         unsigned char version[2];
  26         unsigned char flags[2];
  27         unsigned char compression_method[2];
  28         unsigned char mtime[2];
  29         unsigned char mdate[2];
  30         unsigned char crc32[4];
  31         unsigned char compressed_size[4];
  32         unsigned char size[4];
  33         unsigned char filename_length[2];
  34         unsigned char extra_length[2];
  35         unsigned char _end[1];
  36 };
  37
  38 struct zip_data_desc {
  39         unsigned char magic[4];
  40         unsigned char crc32[4];
  41         unsigned char compressed_size[4];
  42         unsigned char size[4];
  43         unsigned char _end[1];
  44 };
  45
  46 struct zip_dir_header {
  47         unsigned char magic[4];
  48         unsigned char creator_version[2];
  49         unsigned char version[2];
  50         unsigned char flags[2];
  51         unsigned char compression_method[2];
  52         unsigned char mtime[2];
  53         unsigned char mdate[2];
  54         unsigned char crc32[4];
  55         unsigned char compressed_size[4];
  56         unsigned char size[4];
  57         unsigned char filename_length[2];
  58         unsigned char extra_length[2];
  59         unsigned char comment_length[2];
  60         unsigned char disk[2];
  61         unsigned char attr1[2];
  62         unsigned char attr2[4];
  63         unsigned char offset[4];
  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 /*
  80  * On ARM, padding is added at the end of the struct, so a simple
  81  * sizeof(struct ...) reports two bytes more than the payload size
  82  * we're interested in.
  83  */
  84 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  85 #define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
  86 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  87 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  88
  89 static void copy_le16(unsigned char *dest, unsigned int n)
  90 {
  91         dest[0] = 0xff & n;
  92         dest[1] = 0xff & (n >> 010);
  93 }
  94
  95 static void copy_le32(unsigned char *dest, unsigned int n)
  96 {
  97         dest[0] = 0xff & n;
  98         dest[1] = 0xff & (n >> 010);
  99         dest[2] = 0xff & (n >> 020);
 100         dest[3] = 0xff & (n >> 030);
 101 }
 102
 103 static void *zlib_deflate(void *data, unsigned long size,
 104                 int compression_level, unsigned long *compressed_size)
 105 {
 106         git_zstream stream;
 107         unsigned long maxsize;
 108         void *buffer;
 109         int result;
 110
 111         memset(&stream, 0, sizeof(stream));
 112         git_deflate_init(&stream, compression_level);
 113         maxsize = git_deflate_bound(&stream, size);
 114         buffer = xmalloc(maxsize);
 115
 116         stream.next_in = data;
 117         stream.avail_in = size;
 118         stream.next_out = buffer;
 119         stream.avail_out = maxsize;
 120
 121         do {
 122                 result = git_deflate(&stream, Z_FINISH);
 123         } while (result == Z_OK);
 124
 125         if (result != Z_STREAM_END) {
 126                 free(buffer);
 127                 return NULL;
 128         }
 129
 130         git_deflate_end(&stream);
 131         *compressed_size = stream.total_out;
 132
 133         return buffer;
 134 }
 135
 136 static void write_zip_data_desc(unsigned long size,
 137                                 unsigned long compressed_size,
 138                                 unsigned long crc)
 139 {
 140         struct zip_data_desc trailer;
 141
 142         copy_le32(trailer.magic, 0x08074b50);
 143         copy_le32(trailer.crc32, crc);
 144         copy_le32(trailer.compressed_size, compressed_size);
 145         copy_le32(trailer.size, size);
 146         write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 147 }
 148
 149 static void set_zip_dir_data_desc(struct zip_dir_header *header,
 150                                   unsigned long size,
 151                                   unsigned long compressed_size,
 152                                   unsigned long crc)
 153 {
 154         copy_le32(header->crc32, crc);
 155         copy_le32(header->compressed_size, compressed_size);
 156         copy_le32(header->size, size);
 157 }
 158
 159 static void set_zip_header_data_desc(struct zip_local_header *header,
 160                                      unsigned long size,
 161                                      unsigned long compressed_size,
 162                                      unsigned long crc)
 163 {
 164         copy_le32(header->crc32, crc);
 165         copy_le32(header->compressed_size, compressed_size);
 166         copy_le32(header->size, size);
 167 }
 168
 169 static int has_only_ascii(const char *s)
 170 {
 171         for (;;) {
 172                 int c = *s++;
 173                 if (c == '\0')
 174                         return 1;
 175                 if (!isascii(c))
 176                         return 0;
 177         }
 178 }
 179
 180 #define STREAM_BUFFER_SIZE (1024 * 16)
 181
 182 static int write_zip_entry(struct archiver_args *args,
 183                            const unsigned char *sha1,
 184                            const char *path, size_t pathlen,
 185                            unsigned int mode)
 186 {
 187         struct zip_local_header header;
 188         struct zip_dir_header dirent;
 189         unsigned long attr2;
 190         unsigned long compressed_size;
 191         unsigned long crc;
 192         unsigned long direntsize;
 193         int method;
 194         unsigned char *out;
 195         void *deflated = NULL;
 196         void *buffer;
 197         struct git_istream *stream = NULL;
 198         unsigned long flags = 0;
 199         unsigned long size;
 200
 201         crc = crc32(0, NULL, 0);
 202
 203         if (!has_only_ascii(path)) {
 204                 if (is_utf8(path))
 205                         flags |= ZIP_UTF8;
 206                 else
 207                         warning("Path is not valid UTF-8: %s", path);
 208         }
 209
 210         if (pathlen > 0xffff) {
 211                 return error("path too long (%d chars, SHA1: %s): %s",
 212                                 (int)pathlen, sha1_to_hex(sha1), path);
 213         }
 214
 215         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 216                 method = 0;
 217                 attr2 = 16;
 218                 out = NULL;
 219                 size = 0;
 220                 compressed_size = 0;
 221                 buffer = NULL;
 222                 size = 0;
 223         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 224                 enum object_type type = sha1_object_info(sha1, &size);
 225
 226                 method = 0;
 227                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 228                         (mode & 0111) ? ((mode) << 16) : 0;
 229                 if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 230                         method = 8;
 231                 compressed_size = size;
 232
 233                 if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 234                     size > big_file_threshold) {
 235                         stream = open_istream(sha1, &type, &size, NULL);
 236                         if (!stream)
 237                                 return error("cannot stream blob %s",
 238                                              sha1_to_hex(sha1));
 239                         flags |= ZIP_STREAM;
 240                         out = buffer = NULL;
 241                 } else {
 242                         buffer = sha1_file_to_archive(args, path, sha1, mode,
 243                                                       &type, &size);
 244                         if (!buffer)
 245                                 return error("cannot read %s",
 246                                              sha1_to_hex(sha1));
 247                         crc = crc32(crc, buffer, size);
 248                         out = buffer;
 249                 }
 250         } else {
 251                 return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 252                                 sha1_to_hex(sha1));
 253         }
 254
 255         if (buffer && method == 8) {
 256                 deflated = zlib_deflate(buffer, size, args->compression_level,
 257                                 &compressed_size);
 258                 if (deflated && compressed_size - 6 < size) {
 259                         /* ZLIB --> raw compressed data (see RFC 1950) */
 260                         /* CMF and FLG ... */
 261                         out = (unsigned char *)deflated + 2;
 262                         compressed_size -= 6;   /* ... and ADLER32 */
 263                 } else {
 264                         method = 0;
 265                         compressed_size = size;
 266                 }
 267         }
 268
 269         /* make sure we have enough free space in the dictionary */
 270         direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 271         while (zip_dir_size < zip_dir_offset + direntsize) {
 272                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 273                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 274         }
 275
 276         copy_le32(dirent.magic, 0x02014b50);
 277         copy_le16(dirent.creator_version,
 278                 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 279         copy_le16(dirent.version, 10);
 280         copy_le16(dirent.flags, flags);
 281         copy_le16(dirent.compression_method, method);
 282         copy_le16(dirent.mtime, zip_time);
 283         copy_le16(dirent.mdate, zip_date);
 284         set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 285         copy_le16(dirent.filename_length, pathlen);
 286         copy_le16(dirent.extra_length, 0);
 287         copy_le16(dirent.comment_length, 0);
 288         copy_le16(dirent.disk, 0);
 289         copy_le16(dirent.attr1, 0);
 290         copy_le32(dirent.attr2, attr2);
 291         copy_le32(dirent.offset, zip_offset);
 292
 293         copy_le32(header.magic, 0x04034b50);
 294         copy_le16(header.version, 10);
 295         copy_le16(header.flags, flags);
 296         copy_le16(header.compression_method, method);
 297         copy_le16(header.mtime, zip_time);
 298         copy_le16(header.mdate, zip_date);
 299         if (flags & ZIP_STREAM)
 300                 set_zip_header_data_desc(&header, 0, 0, 0);
 301         else
 302                 set_zip_header_data_desc(&header, size, compressed_size, crc);
 303         copy_le16(header.filename_length, pathlen);
 304         copy_le16(header.extra_length, 0);
 305         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 306         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 307         write_or_die(1, path, pathlen);
 308         zip_offset += pathlen;
 309         if (stream && method == 0) {
 310                 unsigned char buf[STREAM_BUFFER_SIZE];
 311                 ssize_t readlen;
 312
 313                 for (;;) {
 314                         readlen = read_istream(stream, buf, sizeof(buf));
 315                         if (readlen <= 0)
 316                                 break;
 317                         crc = crc32(crc, buf, readlen);
 318                         write_or_die(1, buf, readlen);
 319                 }
 320                 close_istream(stream);
 321                 if (readlen)
 322                         return readlen;
 323
 324                 compressed_size = size;
 325                 zip_offset += compressed_size;
 326
 327                 write_zip_data_desc(size, compressed_size, crc);
 328                 zip_offset += ZIP_DATA_DESC_SIZE;
 329
 330                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 331         } else if (stream && method == 8) {
 332                 unsigned char buf[STREAM_BUFFER_SIZE];
 333                 ssize_t readlen;
 334                 git_zstream zstream;
 335                 int result;
 336                 size_t out_len;
 337                 unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 338
 339                 memset(&zstream, 0, sizeof(zstream));
 340                 git_deflate_init(&zstream, args->compression_level);
 341
 342                 compressed_size = 0;
 343                 zstream.next_out = compressed;
 344                 zstream.avail_out = sizeof(compressed);
 345
 346                 for (;;) {
 347                         readlen = read_istream(stream, buf, sizeof(buf));
 348                         if (readlen <= 0)
 349                                 break;
 350                         crc = crc32(crc, buf, readlen);
 351
 352                         zstream.next_in = buf;
 353                         zstream.avail_in = readlen;
 354                         result = git_deflate(&zstream, 0);
 355                         if (result != Z_OK)
 356                                 die("deflate error (%d)", result);
 357                         out = compressed;
 358                         if (!compressed_size)
 359                                 out += 2;
 360                         out_len = zstream.next_out - out;
 361
 362                         if (out_len > 0) {
 363                                 write_or_die(1, out, out_len);
 364                                 compressed_size += out_len;
 365                                 zstream.next_out = compressed;
 366                                 zstream.avail_out = sizeof(compressed);
 367                         }
 368
 369                 }
 370                 close_istream(stream);
 371                 if (readlen)
 372                         return readlen;
 373
 374                 zstream.next_in = buf;
 375                 zstream.avail_in = 0;
 376                 result = git_deflate(&zstream, Z_FINISH);
 377                 if (result != Z_STREAM_END)
 378                         die("deflate error (%d)", result);
 379
 380                 git_deflate_end(&zstream);
 381                 out = compressed;
 382                 if (!compressed_size)
 383                         out += 2;
 384                 out_len = zstream.next_out - out - 4;
 385                 write_or_die(1, out, out_len);
 386                 compressed_size += out_len;
 387                 zip_offset += compressed_size;
 388
 389                 write_zip_data_desc(size, compressed_size, crc);
 390                 zip_offset += ZIP_DATA_DESC_SIZE;
 391
 392                 set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 393         } else if (compressed_size > 0) {
 394                 write_or_die(1, out, compressed_size);
 395                 zip_offset += compressed_size;
 396         }
 397
 398         free(deflated);
 399         free(buffer);
 400
 401         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 402         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 403         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 404         zip_dir_offset += pathlen;
 405         zip_dir_entries++;
 406
 407         return 0;
 408 }
 409
 410 static void write_zip_trailer(const unsigned char *sha1)
 411 {
 412         struct zip_dir_trailer trailer;
 413
 414         copy_le32(trailer.magic, 0x06054b50);
 415         copy_le16(trailer.disk, 0);
 416         copy_le16(trailer.directory_start_disk, 0);
 417         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 418         copy_le16(trailer.entries, zip_dir_entries);
 419         copy_le32(trailer.size, zip_dir_offset);
 420         copy_le32(trailer.offset, zip_offset);
 421         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 422
 423         write_or_die(1, zip_dir, zip_dir_offset);
 424         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 425         if (sha1)
 426                 write_or_die(1, sha1_to_hex(sha1), 40);
 427 }
 428
 429 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 430 {
 431         struct tm *t = localtime(time);
 432
 433         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 434                     (t->tm_year + 1900 - 1980) * 512;
 435         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 436 }
 437
 438 static int write_zip_archive(const struct archiver *ar,
 439                              struct archiver_args *args)
 440 {
 441         int err;
 442
 443         dos_time(&args->time, &zip_date, &zip_time);
 444
 445         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 446         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 447
 448         err = write_archive_entries(args, write_zip_entry);
 449         if (!err)
 450                 write_zip_trailer(args->commit_sha1);
 451
 452         free(zip_dir);
 453
 454         return err;
 455 }
 456
 457 static struct archiver zip_archiver = {
 458         "zip",
 459         write_zip_archive,
 460         ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 461 };
 462
 463 void init_zip_archiver(void)
 464 {
 465         register_archiver(&zip_archiver);
 466 }