archive-zip.con commit glossary: mention 'treeish' as an alternative to 'tree-ish' (36a2a54)
   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
  79struct zip_extra_mtime {
  80        unsigned char magic[2];
  81        unsigned char extra_size[2];
  82        unsigned char flags[1];
  83        unsigned char mtime[4];
  84        unsigned char _end[1];
  85};
  86
  87/*
  88 * On ARM, padding is added at the end of the struct, so a simple
  89 * sizeof(struct ...) reports two bytes more than the payload size
  90 * we're interested in.
  91 */
  92#define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  93#define ZIP_DATA_DESC_SIZE      offsetof(struct zip_data_desc, _end)
  94#define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  95#define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  96#define ZIP_EXTRA_MTIME_SIZE    offsetof(struct zip_extra_mtime, _end)
  97#define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
  98        (ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
  99
 100static void copy_le16(unsigned char *dest, unsigned int n)
 101{
 102        dest[0] = 0xff & n;
 103        dest[1] = 0xff & (n >> 010);
 104}
 105
 106static void copy_le32(unsigned char *dest, unsigned int n)
 107{
 108        dest[0] = 0xff & n;
 109        dest[1] = 0xff & (n >> 010);
 110        dest[2] = 0xff & (n >> 020);
 111        dest[3] = 0xff & (n >> 030);
 112}
 113
 114static void *zlib_deflate_raw(void *data, unsigned long size,
 115                              int compression_level,
 116                              unsigned long *compressed_size)
 117{
 118        git_zstream stream;
 119        unsigned long maxsize;
 120        void *buffer;
 121        int result;
 122
 123        memset(&stream, 0, sizeof(stream));
 124        git_deflate_init_raw(&stream, compression_level);
 125        maxsize = git_deflate_bound(&stream, size);
 126        buffer = xmalloc(maxsize);
 127
 128        stream.next_in = data;
 129        stream.avail_in = size;
 130        stream.next_out = buffer;
 131        stream.avail_out = maxsize;
 132
 133        do {
 134                result = git_deflate(&stream, Z_FINISH);
 135        } while (result == Z_OK);
 136
 137        if (result != Z_STREAM_END) {
 138                free(buffer);
 139                return NULL;
 140        }
 141
 142        git_deflate_end(&stream);
 143        *compressed_size = stream.total_out;
 144
 145        return buffer;
 146}
 147
 148static void write_zip_data_desc(unsigned long size,
 149                                unsigned long compressed_size,
 150                                unsigned long crc)
 151{
 152        struct zip_data_desc trailer;
 153
 154        copy_le32(trailer.magic, 0x08074b50);
 155        copy_le32(trailer.crc32, crc);
 156        copy_le32(trailer.compressed_size, compressed_size);
 157        copy_le32(trailer.size, size);
 158        write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
 159}
 160
 161static void set_zip_dir_data_desc(struct zip_dir_header *header,
 162                                  unsigned long size,
 163                                  unsigned long compressed_size,
 164                                  unsigned long crc)
 165{
 166        copy_le32(header->crc32, crc);
 167        copy_le32(header->compressed_size, compressed_size);
 168        copy_le32(header->size, size);
 169}
 170
 171static void set_zip_header_data_desc(struct zip_local_header *header,
 172                                     unsigned long size,
 173                                     unsigned long compressed_size,
 174                                     unsigned long crc)
 175{
 176        copy_le32(header->crc32, crc);
 177        copy_le32(header->compressed_size, compressed_size);
 178        copy_le32(header->size, size);
 179}
 180
 181static int has_only_ascii(const char *s)
 182{
 183        for (;;) {
 184                int c = *s++;
 185                if (c == '\0')
 186                        return 1;
 187                if (!isascii(c))
 188                        return 0;
 189        }
 190}
 191
 192#define STREAM_BUFFER_SIZE (1024 * 16)
 193
 194static int write_zip_entry(struct archiver_args *args,
 195                           const unsigned char *sha1,
 196                           const char *path, size_t pathlen,
 197                           unsigned int mode)
 198{
 199        struct zip_local_header header;
 200        struct zip_dir_header dirent;
 201        struct zip_extra_mtime extra;
 202        unsigned long attr2;
 203        unsigned long compressed_size;
 204        unsigned long crc;
 205        unsigned long direntsize;
 206        int method;
 207        unsigned char *out;
 208        void *deflated = NULL;
 209        void *buffer;
 210        struct git_istream *stream = NULL;
 211        unsigned long flags = 0;
 212        unsigned long size;
 213
 214        crc = crc32(0, NULL, 0);
 215
 216        if (!has_only_ascii(path)) {
 217                if (is_utf8(path))
 218                        flags |= ZIP_UTF8;
 219                else
 220                        warning("Path is not valid UTF-8: %s", path);
 221        }
 222
 223        if (pathlen > 0xffff) {
 224                return error("path too long (%d chars, SHA1: %s): %s",
 225                                (int)pathlen, sha1_to_hex(sha1), path);
 226        }
 227
 228        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 229                method = 0;
 230                attr2 = 16;
 231                out = NULL;
 232                size = 0;
 233                compressed_size = 0;
 234                buffer = NULL;
 235        } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 236                enum object_type type = sha1_object_info(sha1, &size);
 237
 238                method = 0;
 239                attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 240                        (mode & 0111) ? ((mode) << 16) : 0;
 241                if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
 242                        method = 8;
 243
 244                if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
 245                    size > big_file_threshold) {
 246                        stream = open_istream(sha1, &type, &size, NULL);
 247                        if (!stream)
 248                                return error("cannot stream blob %s",
 249                                             sha1_to_hex(sha1));
 250                        flags |= ZIP_STREAM;
 251                        out = buffer = NULL;
 252                } else {
 253                        buffer = sha1_file_to_archive(args, path, sha1, mode,
 254                                                      &type, &size);
 255                        if (!buffer)
 256                                return error("cannot read %s",
 257                                             sha1_to_hex(sha1));
 258                        crc = crc32(crc, buffer, size);
 259                        out = buffer;
 260                }
 261                compressed_size = (method == 0) ? size : 0;
 262        } else {
 263                return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 264                                sha1_to_hex(sha1));
 265        }
 266
 267        if (buffer && method == 8) {
 268                out = deflated = zlib_deflate_raw(buffer, size,
 269                                                  args->compression_level,
 270                                                  &compressed_size);
 271                if (!out || compressed_size >= size) {
 272                        out = buffer;
 273                        method = 0;
 274                        compressed_size = size;
 275                }
 276        }
 277
 278        copy_le16(extra.magic, 0x5455);
 279        copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
 280        extra.flags[0] = 1;     /* just mtime */
 281        copy_le32(extra.mtime, args->time);
 282
 283        /* make sure we have enough free space in the dictionary */
 284        direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
 285        while (zip_dir_size < zip_dir_offset + direntsize) {
 286                zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 287                zip_dir = xrealloc(zip_dir, zip_dir_size);
 288        }
 289
 290        copy_le32(dirent.magic, 0x02014b50);
 291        copy_le16(dirent.creator_version,
 292                S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 293        copy_le16(dirent.version, 10);
 294        copy_le16(dirent.flags, flags);
 295        copy_le16(dirent.compression_method, method);
 296        copy_le16(dirent.mtime, zip_time);
 297        copy_le16(dirent.mdate, zip_date);
 298        set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 299        copy_le16(dirent.filename_length, pathlen);
 300        copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
 301        copy_le16(dirent.comment_length, 0);
 302        copy_le16(dirent.disk, 0);
 303        copy_le16(dirent.attr1, 0);
 304        copy_le32(dirent.attr2, attr2);
 305        copy_le32(dirent.offset, zip_offset);
 306
 307        copy_le32(header.magic, 0x04034b50);
 308        copy_le16(header.version, 10);
 309        copy_le16(header.flags, flags);
 310        copy_le16(header.compression_method, method);
 311        copy_le16(header.mtime, zip_time);
 312        copy_le16(header.mdate, zip_date);
 313        set_zip_header_data_desc(&header, size, compressed_size, crc);
 314        copy_le16(header.filename_length, pathlen);
 315        copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
 316        write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 317        zip_offset += ZIP_LOCAL_HEADER_SIZE;
 318        write_or_die(1, path, pathlen);
 319        zip_offset += pathlen;
 320        write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
 321        zip_offset += ZIP_EXTRA_MTIME_SIZE;
 322        if (stream && method == 0) {
 323                unsigned char buf[STREAM_BUFFER_SIZE];
 324                ssize_t readlen;
 325
 326                for (;;) {
 327                        readlen = read_istream(stream, buf, sizeof(buf));
 328                        if (readlen <= 0)
 329                                break;
 330                        crc = crc32(crc, buf, readlen);
 331                        write_or_die(1, buf, readlen);
 332                }
 333                close_istream(stream);
 334                if (readlen)
 335                        return readlen;
 336
 337                compressed_size = size;
 338                zip_offset += compressed_size;
 339
 340                write_zip_data_desc(size, compressed_size, crc);
 341                zip_offset += ZIP_DATA_DESC_SIZE;
 342
 343                set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 344        } else if (stream && method == 8) {
 345                unsigned char buf[STREAM_BUFFER_SIZE];
 346                ssize_t readlen;
 347                git_zstream zstream;
 348                int result;
 349                size_t out_len;
 350                unsigned char compressed[STREAM_BUFFER_SIZE * 2];
 351
 352                memset(&zstream, 0, sizeof(zstream));
 353                git_deflate_init_raw(&zstream, args->compression_level);
 354
 355                compressed_size = 0;
 356                zstream.next_out = compressed;
 357                zstream.avail_out = sizeof(compressed);
 358
 359                for (;;) {
 360                        readlen = read_istream(stream, buf, sizeof(buf));
 361                        if (readlen <= 0)
 362                                break;
 363                        crc = crc32(crc, buf, readlen);
 364
 365                        zstream.next_in = buf;
 366                        zstream.avail_in = readlen;
 367                        result = git_deflate(&zstream, 0);
 368                        if (result != Z_OK)
 369                                die("deflate error (%d)", result);
 370                        out_len = zstream.next_out - compressed;
 371
 372                        if (out_len > 0) {
 373                                write_or_die(1, compressed, out_len);
 374                                compressed_size += out_len;
 375                                zstream.next_out = compressed;
 376                                zstream.avail_out = sizeof(compressed);
 377                        }
 378
 379                }
 380                close_istream(stream);
 381                if (readlen)
 382                        return readlen;
 383
 384                zstream.next_in = buf;
 385                zstream.avail_in = 0;
 386                result = git_deflate(&zstream, Z_FINISH);
 387                if (result != Z_STREAM_END)
 388                        die("deflate error (%d)", result);
 389
 390                git_deflate_end(&zstream);
 391                out_len = zstream.next_out - compressed;
 392                write_or_die(1, compressed, out_len);
 393                compressed_size += out_len;
 394                zip_offset += compressed_size;
 395
 396                write_zip_data_desc(size, compressed_size, crc);
 397                zip_offset += ZIP_DATA_DESC_SIZE;
 398
 399                set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 400        } else if (compressed_size > 0) {
 401                write_or_die(1, out, compressed_size);
 402                zip_offset += compressed_size;
 403        }
 404
 405        free(deflated);
 406        free(buffer);
 407
 408        memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 409        zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 410        memcpy(zip_dir + zip_dir_offset, path, pathlen);
 411        zip_dir_offset += pathlen;
 412        memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
 413        zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
 414        zip_dir_entries++;
 415
 416        return 0;
 417}
 418
 419static void write_zip_trailer(const unsigned char *sha1)
 420{
 421        struct zip_dir_trailer trailer;
 422
 423        copy_le32(trailer.magic, 0x06054b50);
 424        copy_le16(trailer.disk, 0);
 425        copy_le16(trailer.directory_start_disk, 0);
 426        copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 427        copy_le16(trailer.entries, zip_dir_entries);
 428        copy_le32(trailer.size, zip_dir_offset);
 429        copy_le32(trailer.offset, zip_offset);
 430        copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 431
 432        write_or_die(1, zip_dir, zip_dir_offset);
 433        write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 434        if (sha1)
 435                write_or_die(1, sha1_to_hex(sha1), 40);
 436}
 437
 438static void dos_time(time_t *time, int *dos_date, int *dos_time)
 439{
 440        struct tm *t = localtime(time);
 441
 442        *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 443                    (t->tm_year + 1900 - 1980) * 512;
 444        *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 445}
 446
 447static int write_zip_archive(const struct archiver *ar,
 448                             struct archiver_args *args)
 449{
 450        int err;
 451
 452        dos_time(&args->time, &zip_date, &zip_time);
 453
 454        zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 455        zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 456
 457        err = write_archive_entries(args, write_zip_entry);
 458        if (!err)
 459                write_zip_trailer(args->commit_sha1);
 460
 461        free(zip_dir);
 462
 463        return err;
 464}
 465
 466static struct archiver zip_archiver = {
 467        "zip",
 468        write_zip_archive,
 469        ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 470};
 471
 472void init_zip_archiver(void)
 473{
 474        register_archiver(&zip_archiver);
 475}