builtin-zip-tree.c

   1 /*
   2  * Copyright (c) 2006 Rene Scharfe
   3  */
   4 #include <time.h>
   5 #include "cache.h"
   6 #include "commit.h"
   7 #include "blob.h"
   8 #include "tree.h"
   9 #include "quote.h"
  10 #include "builtin.h"
  11 #include "archive.h"
  12
  13 static const char zip_tree_usage[] =
  14 "git-zip-tree [-0|...|-9] <tree-ish> [ <base> ]";
  15
  16 static int zip_date;
  17 static int zip_time;
  18
  19 static unsigned char *zip_dir;
  20 static unsigned int zip_dir_size;
  21
  22 static unsigned int zip_offset;
  23 static unsigned int zip_dir_offset;
  24 static unsigned int zip_dir_entries;
  25
  26 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  27
  28 struct zip_local_header {
  29         unsigned char magic[4];
  30         unsigned char version[2];
  31         unsigned char flags[2];
  32         unsigned char compression_method[2];
  33         unsigned char mtime[2];
  34         unsigned char mdate[2];
  35         unsigned char crc32[4];
  36         unsigned char compressed_size[4];
  37         unsigned char size[4];
  38         unsigned char filename_length[2];
  39         unsigned char extra_length[2];
  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 };
  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 };
  72
  73 static void copy_le16(unsigned char *dest, unsigned int n)
  74 {
  75         dest[0] = 0xff & n;
  76         dest[1] = 0xff & (n >> 010);
  77 }
  78
  79 static void copy_le32(unsigned char *dest, unsigned int n)
  80 {
  81         dest[0] = 0xff & n;
  82         dest[1] = 0xff & (n >> 010);
  83         dest[2] = 0xff & (n >> 020);
  84         dest[3] = 0xff & (n >> 030);
  85 }
  86
  87 static void *zlib_deflate(void *data, unsigned long size,
  88                           unsigned long *compressed_size)
  89 {
  90         z_stream stream;
  91         unsigned long maxsize;
  92         void *buffer;
  93         int result;
  94
  95         memset(&stream, 0, sizeof(stream));
  96         deflateInit(&stream, zlib_compression_level);
  97         maxsize = deflateBound(&stream, size);
  98         buffer = xmalloc(maxsize);
  99
 100         stream.next_in = data;
 101         stream.avail_in = size;
 102         stream.next_out = buffer;
 103         stream.avail_out = maxsize;
 104
 105         do {
 106                 result = deflate(&stream, Z_FINISH);
 107         } while (result == Z_OK);
 108
 109         if (result != Z_STREAM_END) {
 110                 free(buffer);
 111                 return NULL;
 112         }
 113
 114         deflateEnd(&stream);
 115         *compressed_size = stream.total_out;
 116
 117         return buffer;
 118 }
 119
 120 static char *construct_path(const char *base, int baselen,
 121                             const char *filename, int isdir, int *pathlen)
 122 {
 123         int filenamelen = strlen(filename);
 124         int len = baselen + filenamelen;
 125         char *path, *p;
 126
 127         if (isdir)
 128                 len++;
 129         p = path = xmalloc(len + 1);
 130
 131         memcpy(p, base, baselen);
 132         p += baselen;
 133         memcpy(p, filename, filenamelen);
 134         p += filenamelen;
 135         if (isdir)
 136                 *p++ = '/';
 137         *p = '\0';
 138
 139         *pathlen = len;
 140
 141         return path;
 142 }
 143
 144 static int write_zip_entry(const unsigned char *sha1,
 145                            const char *base, int baselen,
 146                            const char *filename, unsigned mode, int stage)
 147 {
 148         struct zip_local_header header;
 149         struct zip_dir_header dirent;
 150         unsigned long compressed_size;
 151         unsigned long uncompressed_size;
 152         unsigned long crc;
 153         unsigned long direntsize;
 154         unsigned long size;
 155         int method;
 156         int result = -1;
 157         int pathlen;
 158         unsigned char *out;
 159         char *path;
 160         char type[20];
 161         void *buffer = NULL;
 162         void *deflated = NULL;
 163
 164         crc = crc32(0, Z_NULL, 0);
 165
 166         path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 167         if (pathlen > 0xffff) {
 168                 error("path too long (%d chars, SHA1: %s): %s", pathlen,
 169                       sha1_to_hex(sha1), path);
 170                 goto out;
 171         }
 172
 173         if (S_ISDIR(mode)) {
 174                 method = 0;
 175                 result = READ_TREE_RECURSIVE;
 176                 out = NULL;
 177                 uncompressed_size = 0;
 178                 compressed_size = 0;
 179         } else if (S_ISREG(mode)) {
 180                 method = zlib_compression_level == 0 ? 0 : 8;
 181                 result = 0;
 182                 buffer = read_sha1_file(sha1, type, &size);
 183                 if (!buffer)
 184                         die("cannot read %s", sha1_to_hex(sha1));
 185                 crc = crc32(crc, buffer, size);
 186                 out = buffer;
 187                 uncompressed_size = size;
 188                 compressed_size = size;
 189         } else {
 190                 error("unsupported file mode: 0%o (SHA1: %s)", mode,
 191                       sha1_to_hex(sha1));
 192                 goto out;
 193         }
 194
 195         if (method == 8) {
 196                 deflated = zlib_deflate(buffer, size, &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 = sizeof(struct zip_dir_header) + 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, 0);
 217         copy_le16(dirent.version, 20);
 218         copy_le16(dirent.flags, 0);
 219         copy_le16(dirent.compression_method, method);
 220         copy_le16(dirent.mtime, zip_time);
 221         copy_le16(dirent.mdate, zip_date);
 222         copy_le32(dirent.crc32, crc);
 223         copy_le32(dirent.compressed_size, compressed_size);
 224         copy_le32(dirent.size, uncompressed_size);
 225         copy_le16(dirent.filename_length, pathlen);
 226         copy_le16(dirent.extra_length, 0);
 227         copy_le16(dirent.comment_length, 0);
 228         copy_le16(dirent.disk, 0);
 229         copy_le16(dirent.attr1, 0);
 230         copy_le32(dirent.attr2, 0);
 231         copy_le32(dirent.offset, zip_offset);
 232         memcpy(zip_dir + zip_dir_offset, &dirent, sizeof(struct zip_dir_header));
 233         zip_dir_offset += sizeof(struct zip_dir_header);
 234         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 235         zip_dir_offset += pathlen;
 236         zip_dir_entries++;
 237
 238         copy_le32(header.magic, 0x04034b50);
 239         copy_le16(header.version, 20);
 240         copy_le16(header.flags, 0);
 241         copy_le16(header.compression_method, method);
 242         copy_le16(header.mtime, zip_time);
 243         copy_le16(header.mdate, zip_date);
 244         copy_le32(header.crc32, crc);
 245         copy_le32(header.compressed_size, compressed_size);
 246         copy_le32(header.size, uncompressed_size);
 247         copy_le16(header.filename_length, pathlen);
 248         copy_le16(header.extra_length, 0);
 249         write_or_die(1, &header, sizeof(struct zip_local_header));
 250         zip_offset += sizeof(struct zip_local_header);
 251         write_or_die(1, path, pathlen);
 252         zip_offset += pathlen;
 253         if (compressed_size > 0) {
 254                 write_or_die(1, out, compressed_size);
 255                 zip_offset += compressed_size;
 256         }
 257
 258 out:
 259         free(buffer);
 260         free(deflated);
 261         free(path);
 262
 263         return result;
 264 }
 265
 266 static void write_zip_trailer(const unsigned char *sha1)
 267 {
 268         struct zip_dir_trailer trailer;
 269
 270         copy_le32(trailer.magic, 0x06054b50);
 271         copy_le16(trailer.disk, 0);
 272         copy_le16(trailer.directory_start_disk, 0);
 273         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 274         copy_le16(trailer.entries, zip_dir_entries);
 275         copy_le32(trailer.size, zip_dir_offset);
 276         copy_le32(trailer.offset, zip_offset);
 277         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 278
 279         write_or_die(1, zip_dir, zip_dir_offset);
 280         write_or_die(1, &trailer, sizeof(struct zip_dir_trailer));
 281         if (sha1)
 282                 write_or_die(1, sha1_to_hex(sha1), 40);
 283 }
 284
 285 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 286 {
 287         struct tm *t = localtime(time);
 288
 289         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 290                     (t->tm_year + 1900 - 1980) * 512;
 291         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 292 }
 293
 294 int cmd_zip_tree(int argc, const char **argv, const char *prefix)
 295 {
 296         unsigned char sha1[20];
 297         struct tree *tree;
 298         struct commit *commit;
 299         time_t archive_time;
 300         char *base;
 301         int baselen;
 302
 303         git_config(git_default_config);
 304
 305         if (argc > 1 && argv[1][0] == '-') {
 306                 if (isdigit(argv[1][1]) && argv[1][2] == '\0') {
 307                         zlib_compression_level = argv[1][1] - '0';
 308                         argc--;
 309                         argv++;
 310                 }
 311         }
 312
 313         switch (argc) {
 314         case 3:
 315                 base = xstrdup(argv[2]);
 316                 baselen = strlen(base);
 317                 break;
 318         case 2:
 319                 base = xstrdup("");
 320                 baselen = 0;
 321                 break;
 322         default:
 323                 usage(zip_tree_usage);
 324         }
 325
 326         if (get_sha1(argv[1], sha1))
 327                 die("Not a valid object name %s", argv[1]);
 328
 329         commit = lookup_commit_reference_gently(sha1, 1);
 330         archive_time = commit ? commit->date : time(NULL);
 331         dos_time(&archive_time, &zip_date, &zip_time);
 332
 333         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 334         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 335
 336         tree = parse_tree_indirect(sha1);
 337         if (!tree)
 338                 die("not a tree object");
 339
 340         if (baselen > 0) {
 341                 write_zip_entry(tree->object.sha1, "", 0, base, 040777, 0);
 342                 base = xrealloc(base, baselen + 1);
 343                 base[baselen] = '/';
 344                 baselen++;
 345                 base[baselen] = '\0';
 346         }
 347         read_tree_recursive(tree, base, baselen, 0, NULL, write_zip_entry);
 348         write_zip_trailer(commit ? commit->object.sha1 : NULL);
 349
 350         free(zip_dir);
 351         free(base);
 352
 353         return 0;
 354 }
 355
 356 int write_zip_archive(struct archiver_args *args)
 357 {
 358         int plen = strlen(args->base);
 359
 360         dos_time(&args->time, &zip_date, &zip_time);
 361
 362         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 363         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 364
 365         if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 366                 char *base = xstrdup(args->base);
 367                 int baselen = strlen(base);
 368
 369                 while (baselen > 0 && base[baselen - 1] == '/')
 370                         base[--baselen] = '\0';
 371                 write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 372                 free(base);
 373         }
 374         read_tree_recursive(args->tree, args->base, plen, 0,
 375                             args->pathspec, write_zip_entry);
 376         write_zip_trailer(args->commit_sha1);
 377
 378         free(zip_dir);
 379
 380         return 0;
 381 }
 382
 383 void *parse_extra_zip_args(int argc, const char **argv)
 384 {
 385         for (; argc > 0; argc--, argv++) {
 386                 const char *arg = argv[0];
 387
 388                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 389                         zlib_compression_level = arg[1] - '0';
 390                 else
 391                         die("Unknown argument for zip format: %s", arg);
 392         }
 393         return NULL;
 394 }