archive-zip.con commit diff-format.txt: Combined diff format documentation supplement (0074aba)
   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
  13static int verbose;
  14static int zip_date;
  15static int zip_time;
  16
  17static unsigned char *zip_dir;
  18static unsigned int zip_dir_size;
  19
  20static unsigned int zip_offset;
  21static unsigned int zip_dir_offset;
  22static unsigned int zip_dir_entries;
  23
  24#define ZIP_DIRECTORY_MIN_SIZE  (1024 * 1024)
  25
  26struct 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
  40struct 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
  60struct 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
  71static void copy_le16(unsigned char *dest, unsigned int n)
  72{
  73        dest[0] = 0xff & n;
  74        dest[1] = 0xff & (n >> 010);
  75}
  76
  77static 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
  85static 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
 118static 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
 142static 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 compressed_size;
 149        unsigned long uncompressed_size;
 150        unsigned long crc;
 151        unsigned long direntsize;
 152        unsigned long size;
 153        int method;
 154        int result = -1;
 155        int pathlen;
 156        unsigned char *out;
 157        char *path;
 158        char type[20];
 159        void *buffer = NULL;
 160        void *deflated = NULL;
 161
 162        crc = crc32(0, Z_NULL, 0);
 163
 164        path = construct_path(base, baselen, filename, S_ISDIR(mode), &pathlen);
 165        if (verbose)
 166                fprintf(stderr, "%s\n", path);
 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
 258out:
 259        free(buffer);
 260        free(deflated);
 261        free(path);
 262
 263        return result;
 264}
 265
 266static 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
 285static 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
 294int write_zip_archive(struct archiver_args *args)
 295{
 296        int plen = strlen(args->base);
 297
 298        dos_time(&args->time, &zip_date, &zip_time);
 299
 300        zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
 301        zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
 302        verbose = args->verbose;
 303
 304        if (args->base && plen > 0 && args->base[plen - 1] == '/') {
 305                char *base = xstrdup(args->base);
 306                int baselen = strlen(base);
 307
 308                while (baselen > 0 && base[baselen - 1] == '/')
 309                        base[--baselen] = '\0';
 310                write_zip_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
 311                free(base);
 312        }
 313        read_tree_recursive(args->tree, args->base, plen, 0,
 314                            args->pathspec, write_zip_entry);
 315        write_zip_trailer(args->commit_sha1);
 316
 317        free(zip_dir);
 318
 319        return 0;
 320}
 321
 322void *parse_extra_zip_args(int argc, const char **argv)
 323{
 324        for (; argc > 0; argc--, argv++) {
 325                const char *arg = argv[0];
 326
 327                if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0')
 328                        zlib_compression_level = arg[1] - '0';
 329                else
 330                        die("Unknown argument for zip format: %s", arg);
 331        }
 332        return NULL;
 333}