Andrew's git - gitweb.git/blob

0f763e8022e24f37fd31be341fef4536709a63d8
   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
   9static int zip_date;
  10static int zip_time;
  11
  12static unsigned char *zip_dir;
  13static unsigned int zip_dir_size;
  14
  15static unsigned int zip_offset;
  16static unsigned int zip_dir_offset;
  17static 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
  23struct 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
  38struct 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
  46struct 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
  67struct 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
  89static void copy_le16(unsigned char *dest, unsigned int n)
  90{
  91        dest[0] = 0xff & n;
  92        dest[1] = 0xff & (n >> 010);
  93}
  94
  95static 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
 103static 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
 136static 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
 149static 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
 159static 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
 169static 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
 182static 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
 410static 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
 429static 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
 438static 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
 457static struct archiver zip_archiver = {
 458        "zip",
 459        write_zip_archive,
 460        ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 461};
 462
 463void init_zip_archiver(void)
 464{
 465        register_archiver(&zip_archiver);
 466}