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 verbose;
  17 static int zip_date;
  18 static int zip_time;
  19
  20 static unsigned char *zip_dir;
  21 static unsigned int zip_dir_size;
  22
  23 static unsigned int zip_offset;
  24 static unsigned int zip_dir_offset;
  25 static unsigned int zip_dir_entries;
  26
  27 #define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  28
  29 struct zip_local_header {
  30         unsigned char magic[4];
  31         unsigned char version[2];
  32         unsigned char flags[2];
  33         unsigned char compression_method[2];
  34         unsigned char mtime[2];
  35         unsigned char mdate[2];
  36         unsigned char crc32[4];
  37         unsigned char compressed_size[4];
  38         unsigned char size[4];
  39         unsigned char filename_length[2];
  40         unsigned char extra_length[2];
  41 };
  42
  43 struct zip_dir_header {
  44         unsigned char magic[4];
  45         unsigned char creator_version[2];
  46         unsigned char version[2];
  47         unsigned char flags[2];
  48         unsigned char compression_method[2];
  49         unsigned char mtime[2];
  50         unsigned char mdate[2];
  51         unsigned char crc32[4];
  52         unsigned char compressed_size[4];
  53         unsigned char size[4];
  54         unsigned char filename_length[2];
  55         unsigned char extra_length[2];
  56         unsigned char comment_length[2];
  57         unsigned char disk[2];
  58         unsigned char attr1[2];
  59         unsigned char attr2[4];
  60         unsigned char offset[4];
  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 };
  73
  74 static void copy_le16(unsigned char *dest, unsigned int n)
  75 {
  76         dest[0] = 0xff & n;
  77         dest[1] = 0xff & (n >> 010);
  78 }
  79
  80 static void copy_le32(unsigned char *dest, unsigned int n)
  81 {
  82         dest[0] = 0xff & n;
  83         dest[1] = 0xff & (n >> 010);
  84         dest[2] = 0xff & (n >> 020);
  85         dest[3] = 0xff & (n >> 030);
  86 }
  87
  88 static void *zlib_deflate(void *data, unsigned long size,
  89                           unsigned long *compressed_size)
  90 {
  91         z_stream stream;
  92         unsigned long maxsize;
  93         void *buffer;
  94         int result;
  95
  96         memset(&stream, 0, sizeof(stream));
  97         deflateInit(&stream, zlib_compression_level);
  98         maxsize = deflateBound(&stream, size);
  99         buffer = xmalloc(maxsize);
 100
 101         stream.next_in = data;
 102         stream.avail_in = size;
 103         stream.next_out = buffer;
 104         stream.avail_out = maxsize;
 105
 106         do {
 107                 result = deflate(&stream, Z_FINISH);
 108         } while (result == Z_OK);
 109
 110         if (result != Z_STREAM_END) {
 111                 free(buffer);
 112                 return NULL;
 113         }
 114
 115         deflateEnd(&stream);
 116         *compressed_size = stream.total_out;
 117
 118         return buffer;
 119 }
 120
 121 static char *construct_path(const char *base, int baselen,
 122                             const char *filename, int isdir, int *pathlen)
 123 {
 124         int filenamelen = strlen(filename);
 125         int len = baselen + filenamelen;
 126         char *path, *p;
 127
 128         if (isdir)
 129                 len++;
 130         p = path = xmalloc(len + 1);
 131
 132         memcpy(p, base, baselen);
 133         p += baselen;
 134         memcpy(p, filename, filenamelen);
 135         p += filenamelen;
 136         if (isdir)
 137                 *p++ = '/';
 138         *p = '\0';
 139
 140         *pathlen = len;
 141
 142         return path;
 143 }
 144
 145 static int write_zip_entry(const unsigned char *sha1,
 146                            const char *base, int baselen,
 147                            const char *filename, unsigned mode, int stage)
 148 {
 149         struct zip_local_header header;
 150         struct zip_dir_header dirent;
 151         unsigned long compressed_size;
 152         unsigned long uncompressed_size;
 153         unsigned long crc;
 154         unsigned long direntsize;
 155         unsigned long size;
 156         int method;
 157         int result = -1;
 158         int pathlen;
 159         unsigned char *out;
 160         char *path;
 161         char type[20];
 162         void *buffer = NULL;
 163         void *deflated = NULL;
 164
 165         crc = crc32(0, Z_NULL, 0);
 166
 167         path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 168         if (verbose)
 169                 fprintf(stderr, "%s\n", path);
 170         if (pathlen > 0xffff) {
 171                 error("path too long (%d chars, SHA1: %s): %s", pathlen,
 172                       sha1_to_hex(sha1), path);
 173                 goto out;
 174         }
 175
 176         if (S_ISDIR(mode)) {
 177                 method = 0;
 178                 result = READ_TREE_RECURSIVE;
 179                 out = NULL;
 180                 uncompressed_size = 0;
 181                 compressed_size = 0;
 182         } else if (S_ISREG(mode)) {
 183                 method = zlib_compression_level == 0 ? 0 : 8;
 184                 result = 0;
 185                 buffer = read_sha1_file(sha1, type, &size);
 186                 if (!buffer)
 187                         die("cannot read %s", sha1_to_hex(sha1));
 188                 crc = crc32(crc, buffer, size);
 189                 out = buffer;
 190                 uncompressed_size = size;
 191                 compressed_size = size;
 192         } else {
 193                 error("unsupported file mode: 0%o (SHA1: %s)", mode,
 194                       sha1_to_hex(sha1));
 195                 goto out;
 196         }
 197
 198         if (method == 8) {
 199                 deflated = zlib_deflate(buffer, size, &compressed_size);
 200                 if (deflated && compressed_size - 6 < size) {
 201                         /* ZLIB --> raw compressed data (see RFC 1950) */
 202                         /* CMF and FLG ... */
 203                         out = (unsigned char *)deflated + 2;
 204                         compressed_size -= 6;   /* ... and ADLER32 */
 205                 } else {
 206                         method = 0;
 207                         compressed_size = size;
 208                 }
 209         }
 210
 211         /* make sure we have enough free space in the dictionary */
 212         direntsize = sizeof(struct zip_dir_header) + pathlen;
 213         while (zip_dir_size < zip_dir_offset + direntsize) {
 214                 zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
 215                 zip_dir = xrealloc(zip_dir, zip_dir_size);
 216         }
 217
 218         copy_le32(dirent.magic, 0x02014b50);
 219         copy_le16(dirent.creator_version, 0);
 220         copy_le16(dirent.version, 20);
 221         copy_le16(dirent.flags, 0);
 222         copy_le16(dirent.compression_method, method);
 223         copy_le16(dirent.mtime, zip_time);
 224         copy_le16(dirent.mdate, zip_date);
 225         copy_le32(dirent.crc32, crc);
 226         copy_le32(dirent.compressed_size, compressed_size);
 227         copy_le32(dirent.size, uncompressed_size);
 228         copy_le16(dirent.filename_length, pathlen);
 229         copy_le16(dirent.extra_length, 0);
 230         copy_le16(dirent.comment_length, 0);
 231         copy_le16(dirent.disk, 0);
 232         copy_le16(dirent.attr1, 0);
 233         copy_le32(dirent.attr2, 0);
 234         copy_le32(dirent.offset, zip_offset);
 235         memcpy(zip_dir + zip_dir_offset, &dirent, sizeof(struct zip_dir_header));
 236         zip_dir_offset += sizeof(struct zip_dir_header);
 237         memcpy(zip_dir + zip_dir_offset, path, pathlen);
 238         zip_dir_offset += pathlen;
 239         zip_dir_entries++;
 240
 241         copy_le32(header.magic, 0x04034b50);
 242         copy_le16(header.version, 20);
 243         copy_le16(header.flags, 0);
 244         copy_le16(header.compression_method, method);
 245         copy_le16(header.mtime, zip_time);
 246         copy_le16(header.mdate, zip_date);
 247         copy_le32(header.crc32, crc);
 248         copy_le32(header.compressed_size, compressed_size);
 249         copy_le32(header.size, uncompressed_size);
 250         copy_le16(header.filename_length, pathlen);
 251         copy_le16(header.extra_length, 0);
 252         write_or_die(1, &header, sizeof(struct zip_local_header));
 253         zip_offset += sizeof(struct zip_local_header);
 254         write_or_die(1, path, pathlen);
 255         zip_offset += pathlen;
 256         if (compressed_size > 0) {
 257                 write_or_die(1, out, compressed_size);
 258                 zip_offset += compressed_size;
 259         }
 260
 261 out:
 262         free(buffer);
 263         free(deflated);
 264         free(path);
 265
 266         return result;
 267 }
 268
 269 static void write_zip_trailer(const unsigned char *sha1)
 270 {
 271         struct zip_dir_trailer trailer;
 272
 273         copy_le32(trailer.magic, 0x06054b50);
 274         copy_le16(trailer.disk, 0);
 275         copy_le16(trailer.directory_start_disk, 0);
 276         copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
 277         copy_le16(trailer.entries, zip_dir_entries);
 278         copy_le32(trailer.size, zip_dir_offset);
 279         copy_le32(trailer.offset, zip_offset);
 280         copy_le16(trailer.comment_length, sha1 ? 40 : 0);
 281
 282         write_or_die(1, zip_dir, zip_dir_offset);
 283         write_or_die(1, &trailer, sizeof(struct zip_dir_trailer));
 284         if (sha1)
 285                 write_or_die(1, sha1_to_hex(sha1), 40);
 286 }
 287
 288 static void dos_time(time_t *time, int *dos_date, int *dos_time)
 289 {
 290         struct tm *t = localtime(time);
 291
 292         *dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 293                     (t->tm_year + 1900 - 1980) * 512;
 294         *dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 295 }
 296
 297 int cmd_zip_tree(int argc, const char **argv, const char *prefix)
 298 {
 299         unsigned char sha1[20];
 300         struct tree *tree;
 301         struct commit *commit;
 302         time_t archive_time;
 303         char *base;
 304         int baselen;
 305
 306         git_config(git_default_config);
 307
 308         if (argc > 1 && argv[1][0] == '-') {
 309                 if (isdigit(argv[1][1]) && argv[1][2] == '\0') {
 310                         zlib_compression_level = argv[1][1] - '0';
 311                         argc--;
 312                         argv++;
 313                 }
 314         }
 315
 316         switch (argc) {
 317         case 3:
 318                 base = xstrdup(argv[2]);
 319                 baselen = strlen(base);
 320                 break;
 321         case 2:
 322                 base = xstrdup("");
 323                 baselen = 0;
 324                 break;
 325         default:
 326                 usage(zip_tree_usage);
 327         }
 328
 329         if (get_sha1(argv[1], sha1))
 330                 die("Not a valid object name %s", argv[1]);
 331
 332         commit = lookup_commit_reference_gently(sha1, 1);
 333         archive_time = commit ? commit->date : time(NULL);
 334         dos_time(&archive_time, &zip_date, &zip_time);
 335
 336         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 337         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 338
 339         tree = parse_tree_indirect(sha1);
 340         if (!tree)
 341                 die("not a tree object");
 342
 343         if (baselen > 0) {
 344                 write_zip_entry(tree->object.sha1, "", 0, base, 040777, 0);
 345                 base = xrealloc(base, baselen + 1);
 346                 base[baselen] = '/';
 347                 baselen++;
 348                 base[baselen] = '\0';
 349         }
 350         read_tree_recursive(tree, base, baselen, 0, NULL, write_zip_entry);
 351         write_zip_trailer(commit ? commit->object.sha1 : NULL);
 352
 353         free(zip_dir);
 354         free(base);
 355
 356         return 0;
 357 }
 358
 359 int write_zip_archive(struct archiver_args *args)
 360 {
 361         int plen = strlen(args->base);
 362
 363         dos_time(&args->time, &zip_date, &zip_time);
 364
 365         zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 366         zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 367         verbose = args->verbose;
 368
 369         if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 370                 char *base = xstrdup(args->base);
 371                 int baselen = strlen(base);
 372
 373                 while (baselen > 0 && base[baselen - 1] == '/')
 374                         base[--baselen] = '\0';
 375                 write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 376                 free(base);
 377         }
 378         read_tree_recursive(args->tree, args->base, plen, 0,
 379                             args->pathspec, write_zip_entry);
 380         write_zip_trailer(args->commit_sha1);
 381
 382         free(zip_dir);
 383
 384         return 0;
 385 }
 386
 387 void *parse_extra_zip_args(int argc, const char **argv)
 388 {
 389         for (; argc > 0; argc--, argv++) {
 390                 const char *arg = argv[0];
 391
 392                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 393                         zlib_compression_level = arg[1] - '0';
 394                 else
 395                         die("Unknown argument for zip format: %s", arg);
 396         }
 397         return NULL;
 398 }