Andrew's git - gitweb.git/blob

678569ab2c324d2e0aea7adad1c2390bd5d4c39e
   1/*
   2 * Copyright (c) 2006 Rene Scharfe
   3 */
   4#include "cache.h"
   5#include "archive.h"
   6
   7static int zip_date;
   8static int zip_time;
   9
  10static unsigned char *zip_dir;
  11static unsigned int zip_dir_size;
  12
  13static unsigned int zip_offset;
  14static unsigned int zip_dir_offset;
  15static unsigned int zip_dir_entries;
  16
  17#define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  18
  19struct zip_local_header {
  20        unsigned char magic[4];
  21        unsigned char version[2];
  22        unsigned char flags[2];
  23        unsigned char compression_method[2];
  24        unsigned char mtime[2];
  25        unsigned char mdate[2];
  26        unsigned char crc32[4];
  27        unsigned char compressed_size[4];
  28        unsigned char size[4];
  29        unsigned char filename_length[2];
  30        unsigned char extra_length[2];
  31        unsigned char _end[1];
  32};
  33
  34struct zip_dir_header {
  35        unsigned char magic[4];
  36        unsigned char creator_version[2];
  37        unsigned char version[2];
  38        unsigned char flags[2];
  39        unsigned char compression_method[2];
  40        unsigned char mtime[2];
  41        unsigned char mdate[2];
  42        unsigned char crc32[4];
  43        unsigned char compressed_size[4];
  44        unsigned char size[4];
  45        unsigned char filename_length[2];
  46        unsigned char extra_length[2];
  47        unsigned char comment_length[2];
  48        unsigned char disk[2];
  49        unsigned char attr1[2];
  50        unsigned char attr2[4];
  51        unsigned char offset[4];
  52        unsigned char _end[1];
  53};
  54
  55struct zip_dir_trailer {
  56        unsigned char magic[4];
  57        unsigned char disk[2];
  58        unsigned char directory_start_disk[2];
  59        unsigned char entries_on_this_disk[2];
  60        unsigned char entries[2];
  61        unsigned char size[4];
  62        unsigned char offset[4];
  63        unsigned char comment_length[2];
  64        unsigned char _end[1];
  65};
  66
  67/*
  68 * On ARM, padding is added at the end of the struct, so a simple
  69 * sizeof(struct ...) reports two bytes more than the payload size
  70 * we're interested in.
  71 */
  72#define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  73#define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  74#define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  75
  76static void copy_le16(unsigned char *dest, unsigned int n)
  77{
  78        dest[0] = 0xff & n;
  79        dest[1] = 0xff & (n >> 010);
  80}
  81
  82static void copy_le32(unsigned char *dest, unsigned int n)
  83{
  84        dest[0] = 0xff & n;
  85        dest[1] = 0xff & (n >> 010);
  86        dest[2] = 0xff & (n >> 020);
  87        dest[3] = 0xff & (n >> 030);
  88}
  89
  90static void *zlib_deflate(void *data, unsigned long size,
  91                int compression_level, unsigned long *compressed_size)
  92{
  93        git_zstream stream;
  94        unsigned long maxsize;
  95        void *buffer;
  96        int result;
  97
  98        memset(&stream, 0, sizeof(stream));
  99        git_deflate_init(&stream, compression_level);
 100        maxsize = git_deflate_bound(&stream, size);
 101        buffer = xmalloc(maxsize);
 102
 103        stream.next_in = data;
 104        stream.avail_in = size;
 105        stream.next_out = buffer;
 106        stream.avail_out = maxsize;
 107
 108        do {
 109                result = git_deflate(&stream, Z_FINISH);
 110        } while (result == Z_OK);
 111
 112        if (result != Z_STREAM_END) {
 113                free(buffer);
 114                return NULL;
 115        }
 116
 117        git_deflate_end(&stream);
 118        *compressed_size = stream.total_out;
 119
 120        return buffer;
 121}
 122
 123static void set_zip_dir_data_desc(struct zip_dir_header *header,
 124                                  unsigned long size,
 125                                  unsigned long compressed_size,
 126                                  unsigned long crc)
 127{
 128        copy_le32(header->crc32, crc);
 129        copy_le32(header->compressed_size, compressed_size);
 130        copy_le32(header->size, size);
 131}
 132
 133static void set_zip_header_data_desc(struct zip_local_header *header,
 134                                     unsigned long size,
 135                                     unsigned long compressed_size,
 136                                     unsigned long crc)
 137{
 138        copy_le32(header->crc32, crc);
 139        copy_le32(header->compressed_size, compressed_size);
 140        copy_le32(header->size, size);
 141}
 142
 143static int write_zip_entry(struct archiver_args *args,
 144                           const unsigned char *sha1,
 145                           const char *path, size_t pathlen,
 146                           unsigned int mode)
 147{
 148        struct zip_local_header header;
 149        struct zip_dir_header dirent;
 150        unsigned long attr2;
 151        unsigned long compressed_size;
 152        unsigned long crc;
 153        unsigned long direntsize;
 154        int method;
 155        unsigned char *out;
 156        void *deflated = NULL;
 157        void *buffer;
 158        unsigned long size;
 159
 160        crc = crc32(0, NULL, 0);
 161
 162        if (pathlen > 0xffff) {
 163                return error("path too long (%d chars, SHA1: %s): %s",
 164                                (int)pathlen, sha1_to_hex(sha1), path);
 165        }
 166
 167        if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 168                method = 0;
 169                attr2 = 16;
 170                out = NULL;
 171                size = 0;
 172                compressed_size = 0;
 173                buffer = NULL;
 174                size = 0;
 175        } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 176                enum object_type type;
 177                buffer = sha1_file_to_archive(args, path, sha1, mode, &type, &size);
 178                if (!buffer)
 179                        return error("cannot read %s", sha1_to_hex(sha1));
 180
 181                method = 0;
 182                attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 183                        (mode & 0111) ? ((mode) << 16) : 0;
 184                if (S_ISREG(mode) && args->compression_level != 0)
 185                        method = 8;
 186                crc = crc32(crc, buffer, size);
 187                out = buffer;
 188                compressed_size = size;
 189        } else {
 190                return error("unsupported file mode: 0%o (SHA1: %s)", mode,
 191                                sha1_to_hex(sha1));
 192        }
 193
 194        if (method == 8) {
 195                deflated = zlib_deflate(buffer, size, args->compression_level,
 196                                &compressed_size);
 197                if (deflated && compressed_size - 6 < size) {
 198                        /* ZLIB --> raw compressed data (see RFC 1950) */
 199                        /* CMF and FLG ... */
 200                        out = (unsigned char *)deflated + 2;
 201                        compressed_size -= 6;   /* ... and ADLER32 */
 202                } else {
 203                        method = 0;
 204                        compressed_size = size;
 205                }
 206        }
 207
 208        /* make sure we have enough free space in the dictionary */
 209        direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 210        while (zip_dir_size < zip_dir_offset + direntsize) {
 211                zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 212                zip_dir = xrealloc(zip_dir, zip_dir_size);
 213        }
 214
 215        copy_le32(dirent.magic, 0x02014b50);
 216        copy_le16(dirent.creator_version,
 217                S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 218        copy_le16(dirent.version, 10);
 219        copy_le16(dirent.flags, 0);
 220        copy_le16(dirent.compression_method, method);
 221        copy_le16(dirent.mtime, zip_time);
 222        copy_le16(dirent.mdate, zip_date);
 223        set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
 224        copy_le16(dirent.filename_length, pathlen);
 225        copy_le16(dirent.extra_length, 0);
 226        copy_le16(dirent.comment_length, 0);
 227        copy_le16(dirent.disk, 0);
 228        copy_le16(dirent.attr1, 0);
 229        copy_le32(dirent.attr2, attr2);
 230        copy_le32(dirent.offset, zip_offset);
 231
 232        copy_le32(header.magic, 0x04034b50);
 233        copy_le16(header.version, 10);
 234        copy_le16(header.flags, 0);
 235        copy_le16(header.compression_method, method);
 236        copy_le16(header.mtime, zip_time);
 237        copy_le16(header.mdate, zip_date);
 238        set_zip_header_data_desc(&header, size, compressed_size, crc);
 239        copy_le16(header.filename_length, pathlen);
 240        copy_le16(header.extra_length, 0);
 241        write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 242        zip_offset += ZIP_LOCAL_HEADER_SIZE;
 243        write_or_die(1, path, pathlen);
 244        zip_offset += pathlen;
 245        if (compressed_size > 0) {
 246                write_or_die(1, out, compressed_size);
 247                zip_offset += compressed_size;
 248        }
 249
 250        free(deflated);
 251        free(buffer);
 252
 253        memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 254        zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 255        memcpy(zip_dir + zip_dir_offset, path, pathlen);
 256        zip_dir_offset += pathlen;
 257        zip_dir_entries++;
 258
 259        return 0;
 260}
 261
 262static void write_zip_trailer(const unsigned char *sha1)
 263{
 264        struct zip_dir_trailer trailer;
 265
 266        copy_le32(trailer.magic, 0x06054b50);
 267        copy_le16(trailer.disk, 0);
 268        copy_le16(trailer.directory_start_disk, 0);
 269        copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 270        copy_le16(trailer.entries, zip_dir_entries);
 271        copy_le32(trailer.size, zip_dir_offset);
 272        copy_le32(trailer.offset, zip_offset);
 273        copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 274
 275        write_or_die(1, zip_dir, zip_dir_offset);
 276        write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 277        if (sha1)
 278                write_or_die(1, sha1_to_hex(sha1), 40);
 279}
 280
 281static void dos_time(time_t *time, int *dos_date, int *dos_time)
 282{
 283        struct tm *t = localtime(time);
 284
 285        *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 286                    (t->tm_year + 1900 - 1980) * 512;
 287        *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 288}
 289
 290static int write_zip_archive(const struct archiver *ar,
 291                             struct archiver_args *args)
 292{
 293        int err;
 294
 295        dos_time(&args->time, &zip_date, &zip_time);
 296
 297        zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 298        zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 299
 300        err = write_archive_entries(args, write_zip_entry);
 301        if (!err)
 302                write_zip_trailer(args->commit_sha1);
 303
 304        free(zip_dir);
 305
 306        return err;
 307}
 308
 309static struct archiver zip_archiver = {
 310        "zip",
 311        write_zip_archive,
 312        ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
 313};
 314
 315void init_zip_archiver(void)
 316{
 317        register_archiver(&zip_archiver);
 318}