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