archive-zip.c

   1 /*
   2  * Copyright (c) 2006 Rene Scharfe
   3  */
   4 #include "cache.h"
   5 #include "commit.h"
   6 #include "blob.h"
   7 #include "tree.h"
   8 #include "quote.h"
   9 #include "builtin.h"
  10 #include "archive.h"
  11
  12 static int verbose;
  13 static int zip_date;
  14 static int zip_time;
  15 static const struct commit *commit;
  16 static size_t base_len;
  17
  18 static unsigned char *zip_dir;
  19 static unsigned int zip_dir_size;
  20
  21 static unsigned int zip_offset;
  22 static unsigned int zip_dir_offset;
  23 static unsigned int zip_dir_entries;
  24
  25 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  26
  27 struct zip_local_header {
  28         unsigned char magic[4];
  29         unsigned char version[2];
  30         unsigned char flags[2];
  31         unsigned char compression_method[2];
  32         unsigned char mtime[2];
  33         unsigned char mdate[2];
  34         unsigned char crc32[4];
  35         unsigned char compressed_size[4];
  36         unsigned char size[4];
  37         unsigned char filename_length[2];
  38         unsigned char extra_length[2];
  39         unsigned char _end[1];
  40 };
  41
  42 struct zip_dir_header {
  43         unsigned char magic[4];
  44         unsigned char creator_version[2];
  45         unsigned char version[2];
  46         unsigned char flags[2];
  47         unsigned char compression_method[2];
  48         unsigned char mtime[2];
  49         unsigned char mdate[2];
  50         unsigned char crc32[4];
  51         unsigned char compressed_size[4];
  52         unsigned char size[4];
  53         unsigned char filename_length[2];
  54         unsigned char extra_length[2];
  55         unsigned char comment_length[2];
  56         unsigned char disk[2];
  57         unsigned char attr1[2];
  58         unsigned char attr2[4];
  59         unsigned char offset[4];
  60         unsigned char _end[1];
  61 };
  62
  63 struct zip_dir_trailer {
  64         unsigned char magic[4];
  65         unsigned char disk[2];
  66         unsigned char directory_start_disk[2];
  67         unsigned char entries_on_this_disk[2];
  68         unsigned char entries[2];
  69         unsigned char size[4];
  70         unsigned char offset[4];
  71         unsigned char comment_length[2];
  72         unsigned char _end[1];
  73 };
  74
  75 /*
  76  * On ARM, padding is added at the end of the struct, so a simple
  77  * sizeof(struct ...) reports two bytes more than the payload size
  78  * we're interested in.
  79  */
  80 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  81 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  82 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  83
  84 static void copy_le16(unsigned char *dest, unsigned int n)
  85 {
  86         dest[0] = 0xff & n;
  87         dest[1] = 0xff & (n >> 010);
  88 }
  89
  90 static void copy_le32(unsigned char *dest, unsigned int n)
  91 {
  92         dest[0] = 0xff & n;
  93         dest[1] = 0xff & (n >> 010);
  94         dest[2] = 0xff & (n >> 020);
  95         dest[3] = 0xff & (n >> 030);
  96 }
  97
  98 static void *zlib_deflate(void *data, unsigned long size,
  99                           unsigned long *compressed_size)
 100 {
 101         z_stream stream;
 102         unsigned long maxsize;
 103         void *buffer;
 104         int result;
 105
 106         memset(&stream, 0, sizeof(stream));
 107         deflateInit(&stream, zlib_compression_level);
 108         maxsize = deflateBound(&stream, size);
 109         buffer = xmalloc(maxsize);
 110
 111         stream.next_in = data;
 112         stream.avail_in = size;
 113         stream.next_out = buffer;
 114         stream.avail_out = maxsize;
 115
 116         do {
 117                 result = deflate(&stream, Z_FINISH);
 118         } while (result == Z_OK);
 119
 120         if (result != Z_STREAM_END) {
 121                 free(buffer);
 122                 return NULL;
 123         }
 124
 125         deflateEnd(&stream);
 126         *compressed_size = stream.total_out;
 127
 128         return buffer;
 129 }
 130
 131 static char *construct_path(const char *base, int baselen,
 132                             const char *filename, int isdir, int *pathlen)
 133 {
 134         int filenamelen = strlen(filename);
 135         int len = baselen + filenamelen;
 136         char *path, *p;
 137
 138         if (isdir)
 139                 len++;
 140         p = path = xmalloc(len + 1);
 141
 142         memcpy(p, base, baselen);
 143         p += baselen;
 144         memcpy(p, filename, filenamelen);
 145         p += filenamelen;
 146         if (isdir)
 147                 *p++ = '/';
 148         *p = '\0';
 149
 150         *pathlen = len;
 151
 152         return path;
 153 }
 154
 155 static int write_zip_entry(const unsigned char *sha1,
 156                            const char *base, int baselen,
 157                            const char *filename, unsigned mode, int stage)
 158 {
 159         struct zip_local_header header;
 160         struct zip_dir_header dirent;
 161         unsigned long attr2;
 162         unsigned long compressed_size;
 163         unsigned long uncompressed_size;
 164         unsigned long crc;
 165         unsigned long direntsize;
 166         unsigned long size;
 167         int method;
 168         int result = -1;
 169         int pathlen;
 170         unsigned char *out;
 171         char *path;
 172         enum object_type type;
 173         void *buffer = NULL;
 174         void *deflated = NULL;
 175
 176         crc = crc32(0, NULL, 0);
 177
 178         path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 179         if (verbose)
 180                 fprintf(stderr, "%s\n", path);
 181         if (pathlen > 0xffff) {
 182                 error("path too long (%d chars, SHA1: %s): %s", pathlen,
 183                       sha1_to_hex(sha1), path);
 184                 goto out;
 185         }
 186
 187         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 188                 method = 0;
 189                 attr2 = 16;
 190                 result = (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 191                 out = NULL;
 192                 uncompressed_size = 0;
 193                 compressed_size = 0;
 194         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 195                 method = 0;
 196                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
 197                         (mode & 0111) ? ((mode) << 16) : 0;
 198                 if (S_ISREG(mode) && zlib_compression_level != 0)
 199                         method = 8;
 200                 result = 0;
 201                 buffer = sha1_file_to_archive(path + base_len, sha1, mode,
 202                                 &type, &size, commit);
 203                 if (!buffer)
 204                         die("cannot read %s", sha1_to_hex(sha1));
 205                 crc = crc32(crc, buffer, size);
 206                 out = buffer;
 207                 uncompressed_size = size;
 208                 compressed_size = size;
 209         } else {
 210                 error("unsupported file mode: 0%o (SHA1: %s)", mode,
 211                       sha1_to_hex(sha1));
 212                 goto out;
 213         }
 214
 215         if (method == 8) {
 216                 deflated = zlib_deflate(buffer, size, &compressed_size);
 217                 if (deflated && compressed_size - 6 < size) {
 218                         /* ZLIB --> raw compressed data (see RFC 1950) */
 219                         /* CMF and FLG ... */
 220                         out = (unsigned char *)deflated + 2;
 221                         compressed_size -= 6;   /* ... and ADLER32 */
 222                 } else {
 223                         method = 0;
 224                         compressed_size = size;
 225                 }
 226         }
 227
 228         /* make sure we have enough free space in the dictionary */
 229         direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 230         while (zip_dir_size < zip_dir_offset + direntsize) {
 231                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 232                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 233         }
 234
 235         copy_le32(dirent.magic, 0x02014b50);
 236         copy_le16(dirent.creator_version,
 237                 S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
 238         copy_le16(dirent.version, 10);
 239         copy_le16(dirent.flags, 0);
 240         copy_le16(dirent.compression_method, method);
 241         copy_le16(dirent.mtime, zip_time);
 242         copy_le16(dirent.mdate, zip_date);
 243         copy_le32(dirent.crc32, crc);
 244         copy_le32(dirent.compressed_size, compressed_size);
 245         copy_le32(dirent.size, uncompressed_size);
 246         copy_le16(dirent.filename_length, pathlen);
 247         copy_le16(dirent.extra_length, 0);
 248         copy_le16(dirent.comment_length, 0);
 249         copy_le16(dirent.disk, 0);
 250         copy_le16(dirent.attr1, 0);
 251         copy_le32(dirent.attr2, attr2);
 252         copy_le32(dirent.offset, zip_offset);
 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         copy_le32(header.magic, 0x04034b50);
 260         copy_le16(header.version, 10);
 261         copy_le16(header.flags, 0);
 262         copy_le16(header.compression_method, method);
 263         copy_le16(header.mtime, zip_time);
 264         copy_le16(header.mdate, zip_date);
 265         copy_le32(header.crc32, crc);
 266         copy_le32(header.compressed_size, compressed_size);
 267         copy_le32(header.size, uncompressed_size);
 268         copy_le16(header.filename_length, pathlen);
 269         copy_le16(header.extra_length, 0);
 270         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 271         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 272         write_or_die(1, path, pathlen);
 273         zip_offset += pathlen;
 274         if (compressed_size > 0) {
 275                 write_or_die(1, out, compressed_size);
 276                 zip_offset += compressed_size;
 277         }
 278
 279 out:
 280         free(buffer);
 281         free(deflated);
 282         free(path);
 283
 284         return result;
 285 }
 286
 287 static void write_zip_trailer(const unsigned char *sha1)
 288 {
 289         struct zip_dir_trailer trailer;
 290
 291         copy_le32(trailer.magic, 0x06054b50);
 292         copy_le16(trailer.disk, 0);
 293         copy_le16(trailer.directory_start_disk, 0);
 294         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 295         copy_le16(trailer.entries, zip_dir_entries);
 296         copy_le32(trailer.size, zip_dir_offset);
 297         copy_le32(trailer.offset, zip_offset);
 298         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 299
 300         write_or_die(1, zip_dir, zip_dir_offset);
 301         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 302         if (sha1)
 303                 write_or_die(1, sha1_to_hex(sha1), 40);
 304 }
 305
 306 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 307 {
 308         struct tm *t = localtime(time);
 309
 310         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 311                     (t->tm_year + 1900 - 1980) * 512;
 312         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 313 }
 314
 315 int write_zip_archive(struct archiver_args *args)
 316 {
 317         int plen = strlen(args->base);
 318
 319         dos_time(&args->time, &zip_date, &zip_time);
 320
 321         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 322         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 323         verbose = args->verbose;
 324         commit = args->commit;
 325         base_len = args->base ? strlen(args->base) : 0;
 326
 327         if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 328                 char *base = xstrdup(args->base);
 329                 int baselen = strlen(base);
 330
 331                 while (baselen > 0 && base[baselen - 1] == '/')
 332                         base[--baselen] = '\0';
 333                 write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 334                 free(base);
 335         }
 336         read_tree_recursive(args->tree, args->base, plen, 0,
 337                             args->pathspec, write_zip_entry);
 338         write_zip_trailer(args->commit_sha1);
 339
 340         free(zip_dir);
 341
 342         return 0;
 343 }
 344
 345 void *parse_extra_zip_args(int argc, const char **argv)
 346 {
 347         for (; argc > 0; argc--, argv++) {
 348                 const char *arg = argv[0];
 349
 350                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 351                         zlib_compression_level = arg[1] - '0';
 352                 else
 353                         die("Unknown argument for zip format: %s", arg);
 354         }
 355         return NULL;
 356 }