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
  17 static unsigned char *zip_dir;
  18 static unsigned int zip_dir_size;
  19
  20 static unsigned int zip_offset;
  21 static unsigned int zip_dir_offset;
  22 static unsigned int zip_dir_entries;
  23
  24 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  25
  26 struct zip_local_header {
  27         unsigned char magic[4];
  28         unsigned char version[2];
  29         unsigned char flags[2];
  30         unsigned char compression_method[2];
  31         unsigned char mtime[2];
  32         unsigned char mdate[2];
  33         unsigned char crc32[4];
  34         unsigned char compressed_size[4];
  35         unsigned char size[4];
  36         unsigned char filename_length[2];
  37         unsigned char extra_length[2];
  38         unsigned char _end[1];
  39 };
  40
  41 struct zip_dir_header {
  42         unsigned char magic[4];
  43         unsigned char creator_version[2];
  44         unsigned char version[2];
  45         unsigned char flags[2];
  46         unsigned char compression_method[2];
  47         unsigned char mtime[2];
  48         unsigned char mdate[2];
  49         unsigned char crc32[4];
  50         unsigned char compressed_size[4];
  51         unsigned char size[4];
  52         unsigned char filename_length[2];
  53         unsigned char extra_length[2];
  54         unsigned char comment_length[2];
  55         unsigned char disk[2];
  56         unsigned char attr1[2];
  57         unsigned char attr2[4];
  58         unsigned char offset[4];
  59         unsigned char _end[1];
  60 };
  61
  62 struct zip_dir_trailer {
  63         unsigned char magic[4];
  64         unsigned char disk[2];
  65         unsigned char directory_start_disk[2];
  66         unsigned char entries_on_this_disk[2];
  67         unsigned char entries[2];
  68         unsigned char size[4];
  69         unsigned char offset[4];
  70         unsigned char comment_length[2];
  71         unsigned char _end[1];
  72 };
  73
  74 /*
  75  * On ARM, padding is added at the end of the struct, so a simple
  76  * sizeof(struct ...) reports two bytes more than the payload size
  77  * we're interested in.
  78  */
  79 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  80 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  81 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  82
  83 static void copy_le16(unsigned char *dest, unsigned int n)
  84 {
  85         dest[0] = 0xff & n;
  86         dest[1] = 0xff & (n >> 010);
  87 }
  88
  89 static void copy_le32(unsigned char *dest, unsigned int n)
  90 {
  91         dest[0] = 0xff & n;
  92         dest[1] = 0xff & (n >> 010);
  93         dest[2] = 0xff & (n >> 020);
  94         dest[3] = 0xff & (n >> 030);
  95 }
  96
  97 static void *zlib_deflate(void *data, unsigned long size,
  98                           unsigned long *compressed_size)
  99 {
 100         z_stream stream;
 101         unsigned long maxsize;
 102         void *buffer;
 103         int result;
 104
 105         memset(&stream, 0, sizeof(stream));
 106         deflateInit(&stream, zlib_compression_level);
 107         maxsize = deflateBound(&stream, size);
 108         buffer = xmalloc(maxsize);
 109
 110         stream.next_in = data;
 111         stream.avail_in = size;
 112         stream.next_out = buffer;
 113         stream.avail_out = maxsize;
 114
 115         do {
 116                 result = deflate(&stream, Z_FINISH);
 117         } while (result == Z_OK);
 118
 119         if (result != Z_STREAM_END) {
 120                 free(buffer);
 121                 return NULL;
 122         }
 123
 124         deflateEnd(&stream);
 125         *compressed_size = stream.total_out;
 126
 127         return buffer;
 128 }
 129
 130 static char *construct_path(const char *base, int baselen,
 131                             const char *filename, int isdir, int *pathlen)
 132 {
 133         int filenamelen = strlen(filename);
 134         int len = baselen + filenamelen;
 135         char *path, *p;
 136
 137         if (isdir)
 138                 len++;
 139         p = path = xmalloc(len + 1);
 140
 141         memcpy(p, base, baselen);
 142         p += baselen;
 143         memcpy(p, filename, filenamelen);
 144         p += filenamelen;
 145         if (isdir)
 146                 *p++ = '/';
 147         *p = '\0';
 148
 149         *pathlen = len;
 150
 151         return path;
 152 }
 153
 154 static int write_zip_entry(const unsigned char *sha1,
 155                            const char *base, int baselen,
 156                            const char *filename, unsigned mode, int stage)
 157 {
 158         struct zip_local_header header;
 159         struct zip_dir_header dirent;
 160         unsigned long attr2;
 161         unsigned long compressed_size;
 162         unsigned long uncompressed_size;
 163         unsigned long crc;
 164         unsigned long direntsize;
 165         unsigned long size;
 166         int method;
 167         int result = -1;
 168         int pathlen;
 169         unsigned char *out;
 170         char *path;
 171         enum object_type type;
 172         void *buffer = NULL;
 173         void *deflated = NULL;
 174
 175         crc = crc32(0, NULL, 0);
 176
 177         path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 178         if (verbose)
 179                 fprintf(stderr, "%s\n", path);
 180         if (pathlen > 0xffff) {
 181                 error("path too long (%d chars, SHA1: %s): %s", pathlen,
 182                       sha1_to_hex(sha1), path);
 183                 goto out;
 184         }
 185
 186         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 187                 method = 0;
 188                 attr2 = 16;
 189                 result = (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 190                 out = NULL;
 191                 uncompressed_size = 0;
 192                 compressed_size = 0;
 193         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 194                 method = 0;
 195                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) : 0;
 196                 if (S_ISREG(mode) && zlib_compression_level != 0)
 197                         method = 8;
 198                 result = 0;
 199                 buffer = sha1_file_to_archive(path, sha1, mode, &type, &size,
 200                                               commit);
 201                 if (!buffer)
 202                         die("cannot read %s", sha1_to_hex(sha1));
 203                 crc = crc32(crc, buffer, size);
 204                 out = buffer;
 205                 uncompressed_size = size;
 206                 compressed_size = size;
 207         } else {
 208                 error("unsupported file mode: 0%o (SHA1: %s)", mode,
 209                       sha1_to_hex(sha1));
 210                 goto out;
 211         }
 212
 213         if (method == 8) {
 214                 deflated = zlib_deflate(buffer, size, &compressed_size);
 215                 if (deflated && compressed_size - 6 < size) {
 216                         /* ZLIB --> raw compressed data (see RFC 1950) */
 217                         /* CMF and FLG ... */
 218                         out = (unsigned char *)deflated + 2;
 219                         compressed_size -= 6;   /* ... and ADLER32 */
 220                 } else {
 221                         method = 0;
 222                         compressed_size = size;
 223                 }
 224         }
 225
 226         /* make sure we have enough free space in the dictionary */
 227         direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 228         while (zip_dir_size < zip_dir_offset + direntsize) {
 229                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 230                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 231         }
 232
 233         copy_le32(dirent.magic, 0x02014b50);
 234         copy_le16(dirent.creator_version, S_ISLNK(mode) ? 0x0317 : 0);
 235         copy_le16(dirent.version, 10);
 236         copy_le16(dirent.flags, 0);
 237         copy_le16(dirent.compression_method, method);
 238         copy_le16(dirent.mtime, zip_time);
 239         copy_le16(dirent.mdate, zip_date);
 240         copy_le32(dirent.crc32, crc);
 241         copy_le32(dirent.compressed_size, compressed_size);
 242         copy_le32(dirent.size, uncompressed_size);
 243         copy_le16(dirent.filename_length, pathlen);
 244         copy_le16(dirent.extra_length, 0);
 245         copy_le16(dirent.comment_length, 0);
 246         copy_le16(dirent.disk, 0);
 247         copy_le16(dirent.attr1, 0);
 248         copy_le32(dirent.attr2, attr2);
 249         copy_le32(dirent.offset, zip_offset);
 250         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 251         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 252         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 253         zip_dir_offset += pathlen;
 254         zip_dir_entries++;
 255
 256         copy_le32(header.magic, 0x04034b50);
 257         copy_le16(header.version, 10);
 258         copy_le16(header.flags, 0);
 259         copy_le16(header.compression_method, method);
 260         copy_le16(header.mtime, zip_time);
 261         copy_le16(header.mdate, zip_date);
 262         copy_le32(header.crc32, crc);
 263         copy_le32(header.compressed_size, compressed_size);
 264         copy_le32(header.size, uncompressed_size);
 265         copy_le16(header.filename_length, pathlen);
 266         copy_le16(header.extra_length, 0);
 267         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 268         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 269         write_or_die(1, path, pathlen);
 270         zip_offset += pathlen;
 271         if (compressed_size > 0) {
 272                 write_or_die(1, out, compressed_size);
 273                 zip_offset += compressed_size;
 274         }
 275
 276 out:
 277         free(buffer);
 278         free(deflated);
 279         free(path);
 280
 281         return result;
 282 }
 283
 284 static void write_zip_trailer(const unsigned char *sha1)
 285 {
 286         struct zip_dir_trailer trailer;
 287
 288         copy_le32(trailer.magic, 0x06054b50);
 289         copy_le16(trailer.disk, 0);
 290         copy_le16(trailer.directory_start_disk, 0);
 291         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 292         copy_le16(trailer.entries, zip_dir_entries);
 293         copy_le32(trailer.size, zip_dir_offset);
 294         copy_le32(trailer.offset, zip_offset);
 295         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 296
 297         write_or_die(1, zip_dir, zip_dir_offset);
 298         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 299         if (sha1)
 300                 write_or_die(1, sha1_to_hex(sha1), 40);
 301 }
 302
 303 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 304 {
 305         struct tm *t = localtime(time);
 306
 307         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 308                     (t->tm_year + 1900 - 1980) * 512;
 309         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 310 }
 311
 312 int write_zip_archive(struct archiver_args *args)
 313 {
 314         int plen = strlen(args->base);
 315
 316         dos_time(&args->time, &zip_date, &zip_time);
 317
 318         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 319         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 320         verbose = args->verbose;
 321         commit = args->commit;
 322
 323         if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 324                 char *base = xstrdup(args->base);
 325                 int baselen = strlen(base);
 326
 327                 while (baselen > 0 && base[baselen - 1] == '/')
 328                         base[--baselen] = '\0';
 329                 write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 330                 free(base);
 331         }
 332         read_tree_recursive(args->tree, args->base, plen, 0,
 333                             args->pathspec, write_zip_entry);
 334         write_zip_trailer(args->commit_sha1);
 335
 336         free(zip_dir);
 337
 338         return 0;
 339 }
 340
 341 void *parse_extra_zip_args(int argc, const char **argv)
 342 {
 343         for (; argc > 0; argc--, argv++) {
 344                 const char *arg = argv[0];
 345
 346                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 347                         zlib_compression_level = arg[1] - '0';
 348                 else
 349                         die("Unknown argument for zip format: %s", arg);
 350         }
 351         return NULL;
 352 }