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
  16 static unsigned char *zip_dir;
  17 static unsigned int zip_dir_size;
  18
  19 static unsigned int zip_offset;
  20 static unsigned int zip_dir_offset;
  21 static unsigned int zip_dir_entries;
  22
  23 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  24
  25 struct zip_local_header {
  26         unsigned char magic[4];
  27         unsigned char version[2];
  28         unsigned char flags[2];
  29         unsigned char compression_method[2];
  30         unsigned char mtime[2];
  31         unsigned char mdate[2];
  32         unsigned char crc32[4];
  33         unsigned char compressed_size[4];
  34         unsigned char size[4];
  35         unsigned char filename_length[2];
  36         unsigned char extra_length[2];
  37         unsigned char _end[1];
  38 };
  39
  40 struct zip_dir_header {
  41         unsigned char magic[4];
  42         unsigned char creator_version[2];
  43         unsigned char version[2];
  44         unsigned char flags[2];
  45         unsigned char compression_method[2];
  46         unsigned char mtime[2];
  47         unsigned char mdate[2];
  48         unsigned char crc32[4];
  49         unsigned char compressed_size[4];
  50         unsigned char size[4];
  51         unsigned char filename_length[2];
  52         unsigned char extra_length[2];
  53         unsigned char comment_length[2];
  54         unsigned char disk[2];
  55         unsigned char attr1[2];
  56         unsigned char attr2[4];
  57         unsigned char offset[4];
  58         unsigned char _end[1];
  59 };
  60
  61 struct zip_dir_trailer {
  62         unsigned char magic[4];
  63         unsigned char disk[2];
  64         unsigned char directory_start_disk[2];
  65         unsigned char entries_on_this_disk[2];
  66         unsigned char entries[2];
  67         unsigned char size[4];
  68         unsigned char offset[4];
  69         unsigned char comment_length[2];
  70         unsigned char _end[1];
  71 };
  72
  73 /*
  74  * On ARM, padding is added at the end of the struct, so a simple
  75  * sizeof(struct ...) reports two bytes more than the payload size
  76  * we're interested in.
  77  */
  78 #define ZIP_LOCAL_HEADER_SIZE   offsetof(struct zip_local_header, _end)
  79 #define ZIP_DIR_HEADER_SIZE     offsetof(struct zip_dir_header, _end)
  80 #define ZIP_DIR_TRAILER_SIZE    offsetof(struct zip_dir_trailer, _end)
  81
  82 static void copy_le16(unsigned char *dest, unsigned int n)
  83 {
  84         dest[0] = 0xff & n;
  85         dest[1] = 0xff & (n >> 010);
  86 }
  87
  88 static void copy_le32(unsigned char *dest, unsigned int n)
  89 {
  90         dest[0] = 0xff & n;
  91         dest[1] = 0xff & (n >> 010);
  92         dest[2] = 0xff & (n >> 020);
  93         dest[3] = 0xff & (n >> 030);
  94 }
  95
  96 static void *zlib_deflate(void *data, unsigned long size,
  97                           unsigned long *compressed_size)
  98 {
  99         z_stream stream;
 100         unsigned long maxsize;
 101         void *buffer;
 102         int result;
 103
 104         memset(&stream, 0, sizeof(stream));
 105         deflateInit(&stream, zlib_compression_level);
 106         maxsize = deflateBound(&stream, size);
 107         buffer = xmalloc(maxsize);
 108
 109         stream.next_in = data;
 110         stream.avail_in = size;
 111         stream.next_out = buffer;
 112         stream.avail_out = maxsize;
 113
 114         do {
 115                 result = deflate(&stream, Z_FINISH);
 116         } while (result == Z_OK);
 117
 118         if (result != Z_STREAM_END) {
 119                 free(buffer);
 120                 return NULL;
 121         }
 122
 123         deflateEnd(&stream);
 124         *compressed_size = stream.total_out;
 125
 126         return buffer;
 127 }
 128
 129 static char *construct_path(const char *base, int baselen,
 130                             const char *filename, int isdir, int *pathlen)
 131 {
 132         int filenamelen = strlen(filename);
 133         int len = baselen + filenamelen;
 134         char *path, *p;
 135
 136         if (isdir)
 137                 len++;
 138         p = path = xmalloc(len + 1);
 139
 140         memcpy(p, base, baselen);
 141         p += baselen;
 142         memcpy(p, filename, filenamelen);
 143         p += filenamelen;
 144         if (isdir)
 145                 *p++ = '/';
 146         *p = '\0';
 147
 148         *pathlen = len;
 149
 150         return path;
 151 }
 152
 153 static int write_zip_entry(const unsigned char *sha1,
 154                            const char *base, int baselen,
 155                            const char *filename, unsigned mode, int stage)
 156 {
 157         struct zip_local_header header;
 158         struct zip_dir_header dirent;
 159         unsigned long attr2;
 160         unsigned long compressed_size;
 161         unsigned long uncompressed_size;
 162         unsigned long crc;
 163         unsigned long direntsize;
 164         unsigned long size;
 165         int method;
 166         int result = -1;
 167         int pathlen;
 168         unsigned char *out;
 169         char *path;
 170         enum object_type type;
 171         void *buffer = NULL;
 172         void *deflated = NULL;
 173
 174         crc = crc32(0, NULL, 0);
 175
 176         path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 177         if (verbose)
 178                 fprintf(stderr, "%s\n", path);
 179         if (pathlen > 0xffff) {
 180                 error("path too long (%d chars, SHA1: %s): %s", pathlen,
 181                       sha1_to_hex(sha1), path);
 182                 goto out;
 183         }
 184
 185         if (S_ISDIR(mode)) {
 186                 method = 0;
 187                 attr2 = 16;
 188                 result = READ_TREE_RECURSIVE;
 189                 out = NULL;
 190                 uncompressed_size = 0;
 191                 compressed_size = 0;
 192         } else if (S_ISREG(mode) || S_ISLNK(mode)) {
 193                 method = 0;
 194                 attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) : 0;
 195                 if (S_ISREG(mode) && zlib_compression_level != 0)
 196                         method = 8;
 197                 result = 0;
 198                 buffer = read_sha1_file(sha1, &type, &size);
 199                 if (!buffer)
 200                         die("cannot read %s", sha1_to_hex(sha1));
 201                 crc = crc32(crc, buffer, size);
 202                 out = buffer;
 203                 uncompressed_size = size;
 204                 compressed_size = size;
 205         } else {
 206                 error("unsupported file mode: 0%o (SHA1: %s)", mode,
 207                       sha1_to_hex(sha1));
 208                 goto out;
 209         }
 210
 211         if (method == 8) {
 212                 deflated = zlib_deflate(buffer, size, &compressed_size);
 213                 if (deflated && compressed_size - 6 < size) {
 214                         /* ZLIB --> raw compressed data (see RFC 1950) */
 215                         /* CMF and FLG ... */
 216                         out = (unsigned char *)deflated + 2;
 217                         compressed_size -= 6;   /* ... and ADLER32 */
 218                 } else {
 219                         method = 0;
 220                         compressed_size = size;
 221                 }
 222         }
 223
 224         /* make sure we have enough free space in the dictionary */
 225         direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
 226         while (zip_dir_size < zip_dir_offset + direntsize) {
 227                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 228                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 229         }
 230
 231         copy_le32(dirent.magic, 0x02014b50);
 232         copy_le16(dirent.creator_version, S_ISLNK(mode) ? 0x0317 : 0);
 233         copy_le16(dirent.version, 10);
 234         copy_le16(dirent.flags, 0);
 235         copy_le16(dirent.compression_method, method);
 236         copy_le16(dirent.mtime, zip_time);
 237         copy_le16(dirent.mdate, zip_date);
 238         copy_le32(dirent.crc32, crc);
 239         copy_le32(dirent.compressed_size, compressed_size);
 240         copy_le32(dirent.size, uncompressed_size);
 241         copy_le16(dirent.filename_length, pathlen);
 242         copy_le16(dirent.extra_length, 0);
 243         copy_le16(dirent.comment_length, 0);
 244         copy_le16(dirent.disk, 0);
 245         copy_le16(dirent.attr1, 0);
 246         copy_le32(dirent.attr2, attr2);
 247         copy_le32(dirent.offset, zip_offset);
 248         memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
 249         zip_dir_offset += ZIP_DIR_HEADER_SIZE;
 250         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 251         zip_dir_offset += pathlen;
 252         zip_dir_entries++;
 253
 254         copy_le32(header.magic, 0x04034b50);
 255         copy_le16(header.version, 10);
 256         copy_le16(header.flags, 0);
 257         copy_le16(header.compression_method, method);
 258         copy_le16(header.mtime, zip_time);
 259         copy_le16(header.mdate, zip_date);
 260         copy_le32(header.crc32, crc);
 261         copy_le32(header.compressed_size, compressed_size);
 262         copy_le32(header.size, uncompressed_size);
 263         copy_le16(header.filename_length, pathlen);
 264         copy_le16(header.extra_length, 0);
 265         write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
 266         zip_offset += ZIP_LOCAL_HEADER_SIZE;
 267         write_or_die(1, path, pathlen);
 268         zip_offset += pathlen;
 269         if (compressed_size > 0) {
 270                 write_or_die(1, out, compressed_size);
 271                 zip_offset += compressed_size;
 272         }
 273
 274 out:
 275         free(buffer);
 276         free(deflated);
 277         free(path);
 278
 279         return result;
 280 }
 281
 282 static void write_zip_trailer(const unsigned char *sha1)
 283 {
 284         struct zip_dir_trailer trailer;
 285
 286         copy_le32(trailer.magic, 0x06054b50);
 287         copy_le16(trailer.disk, 0);
 288         copy_le16(trailer.directory_start_disk, 0);
 289         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 290         copy_le16(trailer.entries, zip_dir_entries);
 291         copy_le32(trailer.size, zip_dir_offset);
 292         copy_le32(trailer.offset, zip_offset);
 293         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 294
 295         write_or_die(1, zip_dir, zip_dir_offset);
 296         write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
 297         if (sha1)
 298                 write_or_die(1, sha1_to_hex(sha1), 40);
 299 }
 300
 301 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 302 {
 303         struct tm *t = localtime(time);
 304
 305         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 306                     (t->tm_year + 1900 - 1980) * 512;
 307         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 308 }
 309
 310 int write_zip_archive(struct archiver_args *args)
 311 {
 312         int plen = strlen(args->base);
 313
 314         dos_time(&args->time, &zip_date, &zip_time);
 315
 316         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 317         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 318         verbose = args->verbose;
 319
 320         if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 321                 char *base = xstrdup(args->base);
 322                 int baselen = strlen(base);
 323
 324                 while (baselen > 0 && base[baselen - 1] == '/')
 325                         base[--baselen] = '\0';
 326                 write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 327                 free(base);
 328         }
 329         read_tree_recursive(args->tree, args->base, plen, 0,
 330                             args->pathspec, write_zip_entry);
 331         write_zip_trailer(args->commit_sha1);
 332
 333         free(zip_dir);
 334
 335         return 0;
 336 }
 337
 338 void *parse_extra_zip_args(int argc, const char **argv)
 339 {
 340         for (; argc > 0; argc--, argv++) {
 341                 const char *arg = argv[0];
 342
 343                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 344                         zlib_compression_level = arg[1] - '0';
 345                 else
 346                         die("Unknown argument for zip format: %s", arg);
 347         }
 348         return NULL;
 349 }