git/archive-zip.c
René Scharfe 227bf59806 archive-zip: write extended timestamp
File modification times in ZIP files are encoded in DOS format: local
time with a granularity of two seconds.  Add an extra field to all
archive entries to also record the mtime in Unix' fashion, as UTC with
a granularity of one second.

This has the desirable side-effect of convincing Info-ZIP unzip 6.00
to respect general purpose flag 11, which is used to indicate that a
file name is encoded in UTF-8.  Any extra field would do, actually,
but the extended timestamp is a reasonably small one (22 bytes per
entry).  Archives created by Info-ZIP zip 3.0 contain it, too (but
with ctime and atime as well).

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-24 10:22:03 -07:00

488 lines
12 KiB
C

/*
* Copyright (c) 2006 Rene Scharfe
*/
#include "cache.h"
#include "archive.h"
#include "streaming.h"
#include "utf8.h"
static int zip_date;
static int zip_time;
static unsigned char *zip_dir;
static unsigned int zip_dir_size;
static unsigned int zip_offset;
static unsigned int zip_dir_offset;
static unsigned int zip_dir_entries;
#define ZIP_DIRECTORY_MIN_SIZE (1024 * 1024)
#define ZIP_STREAM (1 << 3)
#define ZIP_UTF8 (1 << 11)
struct zip_local_header {
unsigned char magic[4];
unsigned char version[2];
unsigned char flags[2];
unsigned char compression_method[2];
unsigned char mtime[2];
unsigned char mdate[2];
unsigned char crc32[4];
unsigned char compressed_size[4];
unsigned char size[4];
unsigned char filename_length[2];
unsigned char extra_length[2];
unsigned char _end[1];
};
struct zip_data_desc {
unsigned char magic[4];
unsigned char crc32[4];
unsigned char compressed_size[4];
unsigned char size[4];
unsigned char _end[1];
};
struct zip_dir_header {
unsigned char magic[4];
unsigned char creator_version[2];
unsigned char version[2];
unsigned char flags[2];
unsigned char compression_method[2];
unsigned char mtime[2];
unsigned char mdate[2];
unsigned char crc32[4];
unsigned char compressed_size[4];
unsigned char size[4];
unsigned char filename_length[2];
unsigned char extra_length[2];
unsigned char comment_length[2];
unsigned char disk[2];
unsigned char attr1[2];
unsigned char attr2[4];
unsigned char offset[4];
unsigned char _end[1];
};
struct zip_dir_trailer {
unsigned char magic[4];
unsigned char disk[2];
unsigned char directory_start_disk[2];
unsigned char entries_on_this_disk[2];
unsigned char entries[2];
unsigned char size[4];
unsigned char offset[4];
unsigned char comment_length[2];
unsigned char _end[1];
};
struct zip_extra_mtime {
unsigned char magic[2];
unsigned char extra_size[2];
unsigned char flags[1];
unsigned char mtime[4];
unsigned char _end[1];
};
/*
* On ARM, padding is added at the end of the struct, so a simple
* sizeof(struct ...) reports two bytes more than the payload size
* we're interested in.
*/
#define ZIP_LOCAL_HEADER_SIZE offsetof(struct zip_local_header, _end)
#define ZIP_DATA_DESC_SIZE offsetof(struct zip_data_desc, _end)
#define ZIP_DIR_HEADER_SIZE offsetof(struct zip_dir_header, _end)
#define ZIP_DIR_TRAILER_SIZE offsetof(struct zip_dir_trailer, _end)
#define ZIP_EXTRA_MTIME_SIZE offsetof(struct zip_extra_mtime, _end)
#define ZIP_EXTRA_MTIME_PAYLOAD_SIZE \
(ZIP_EXTRA_MTIME_SIZE - offsetof(struct zip_extra_mtime, flags))
static void copy_le16(unsigned char *dest, unsigned int n)
{
dest[0] = 0xff & n;
dest[1] = 0xff & (n >> 010);
}
static void copy_le32(unsigned char *dest, unsigned int n)
{
dest[0] = 0xff & n;
dest[1] = 0xff & (n >> 010);
dest[2] = 0xff & (n >> 020);
dest[3] = 0xff & (n >> 030);
}
static void *zlib_deflate(void *data, unsigned long size,
int compression_level, unsigned long *compressed_size)
{
git_zstream stream;
unsigned long maxsize;
void *buffer;
int result;
memset(&stream, 0, sizeof(stream));
git_deflate_init(&stream, compression_level);
maxsize = git_deflate_bound(&stream, size);
buffer = xmalloc(maxsize);
stream.next_in = data;
stream.avail_in = size;
stream.next_out = buffer;
stream.avail_out = maxsize;
do {
result = git_deflate(&stream, Z_FINISH);
} while (result == Z_OK);
if (result != Z_STREAM_END) {
free(buffer);
return NULL;
}
git_deflate_end(&stream);
*compressed_size = stream.total_out;
return buffer;
}
static void write_zip_data_desc(unsigned long size,
unsigned long compressed_size,
unsigned long crc)
{
struct zip_data_desc trailer;
copy_le32(trailer.magic, 0x08074b50);
copy_le32(trailer.crc32, crc);
copy_le32(trailer.compressed_size, compressed_size);
copy_le32(trailer.size, size);
write_or_die(1, &trailer, ZIP_DATA_DESC_SIZE);
}
static void set_zip_dir_data_desc(struct zip_dir_header *header,
unsigned long size,
unsigned long compressed_size,
unsigned long crc)
{
copy_le32(header->crc32, crc);
copy_le32(header->compressed_size, compressed_size);
copy_le32(header->size, size);
}
static void set_zip_header_data_desc(struct zip_local_header *header,
unsigned long size,
unsigned long compressed_size,
unsigned long crc)
{
copy_le32(header->crc32, crc);
copy_le32(header->compressed_size, compressed_size);
copy_le32(header->size, size);
}
static int has_only_ascii(const char *s)
{
for (;;) {
int c = *s++;
if (c == '\0')
return 1;
if (!isascii(c))
return 0;
}
}
#define STREAM_BUFFER_SIZE (1024 * 16)
static int write_zip_entry(struct archiver_args *args,
const unsigned char *sha1,
const char *path, size_t pathlen,
unsigned int mode)
{
struct zip_local_header header;
struct zip_dir_header dirent;
struct zip_extra_mtime extra;
unsigned long attr2;
unsigned long compressed_size;
unsigned long crc;
unsigned long direntsize;
int method;
unsigned char *out;
void *deflated = NULL;
void *buffer;
struct git_istream *stream = NULL;
unsigned long flags = 0;
unsigned long size;
crc = crc32(0, NULL, 0);
if (!has_only_ascii(path)) {
if (is_utf8(path))
flags |= ZIP_UTF8;
else
warning("Path is not valid UTF-8: %s", path);
}
if (pathlen > 0xffff) {
return error("path too long (%d chars, SHA1: %s): %s",
(int)pathlen, sha1_to_hex(sha1), path);
}
if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
method = 0;
attr2 = 16;
out = NULL;
size = 0;
compressed_size = 0;
buffer = NULL;
size = 0;
} else if (S_ISREG(mode) || S_ISLNK(mode)) {
enum object_type type = sha1_object_info(sha1, &size);
method = 0;
attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
(mode & 0111) ? ((mode) << 16) : 0;
if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
method = 8;
compressed_size = size;
if (S_ISREG(mode) && type == OBJ_BLOB && !args->convert &&
size > big_file_threshold) {
stream = open_istream(sha1, &type, &size, NULL);
if (!stream)
return error("cannot stream blob %s",
sha1_to_hex(sha1));
flags |= ZIP_STREAM;
out = buffer = NULL;
} else {
buffer = sha1_file_to_archive(args, path, sha1, mode,
&type, &size);
if (!buffer)
return error("cannot read %s",
sha1_to_hex(sha1));
crc = crc32(crc, buffer, size);
out = buffer;
}
} else {
return error("unsupported file mode: 0%o (SHA1: %s)", mode,
sha1_to_hex(sha1));
}
if (buffer && method == 8) {
deflated = zlib_deflate(buffer, size, args->compression_level,
&compressed_size);
if (deflated && compressed_size - 6 < size) {
/* ZLIB --> raw compressed data (see RFC 1950) */
/* CMF and FLG ... */
out = (unsigned char *)deflated + 2;
compressed_size -= 6; /* ... and ADLER32 */
} else {
method = 0;
compressed_size = size;
}
}
copy_le16(extra.magic, 0x5455);
copy_le16(extra.extra_size, ZIP_EXTRA_MTIME_PAYLOAD_SIZE);
extra.flags[0] = 1; /* just mtime */
copy_le32(extra.mtime, args->time);
/* make sure we have enough free space in the dictionary */
direntsize = ZIP_DIR_HEADER_SIZE + pathlen + ZIP_EXTRA_MTIME_SIZE;
while (zip_dir_size < zip_dir_offset + direntsize) {
zip_dir_size += ZIP_DIRECTORY_MIN_SIZE;
zip_dir = xrealloc(zip_dir, zip_dir_size);
}
copy_le32(dirent.magic, 0x02014b50);
copy_le16(dirent.creator_version,
S_ISLNK(mode) || (S_ISREG(mode) && (mode & 0111)) ? 0x0317 : 0);
copy_le16(dirent.version, 10);
copy_le16(dirent.flags, flags);
copy_le16(dirent.compression_method, method);
copy_le16(dirent.mtime, zip_time);
copy_le16(dirent.mdate, zip_date);
set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
copy_le16(dirent.filename_length, pathlen);
copy_le16(dirent.extra_length, ZIP_EXTRA_MTIME_SIZE);
copy_le16(dirent.comment_length, 0);
copy_le16(dirent.disk, 0);
copy_le16(dirent.attr1, 0);
copy_le32(dirent.attr2, attr2);
copy_le32(dirent.offset, zip_offset);
copy_le32(header.magic, 0x04034b50);
copy_le16(header.version, 10);
copy_le16(header.flags, flags);
copy_le16(header.compression_method, method);
copy_le16(header.mtime, zip_time);
copy_le16(header.mdate, zip_date);
if (flags & ZIP_STREAM)
set_zip_header_data_desc(&header, 0, 0, 0);
else
set_zip_header_data_desc(&header, size, compressed_size, crc);
copy_le16(header.filename_length, pathlen);
copy_le16(header.extra_length, ZIP_EXTRA_MTIME_SIZE);
write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
zip_offset += ZIP_LOCAL_HEADER_SIZE;
write_or_die(1, path, pathlen);
zip_offset += pathlen;
write_or_die(1, &extra, ZIP_EXTRA_MTIME_SIZE);
zip_offset += ZIP_EXTRA_MTIME_SIZE;
if (stream && method == 0) {
unsigned char buf[STREAM_BUFFER_SIZE];
ssize_t readlen;
for (;;) {
readlen = read_istream(stream, buf, sizeof(buf));
if (readlen <= 0)
break;
crc = crc32(crc, buf, readlen);
write_or_die(1, buf, readlen);
}
close_istream(stream);
if (readlen)
return readlen;
compressed_size = size;
zip_offset += compressed_size;
write_zip_data_desc(size, compressed_size, crc);
zip_offset += ZIP_DATA_DESC_SIZE;
set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
} else if (stream && method == 8) {
unsigned char buf[STREAM_BUFFER_SIZE];
ssize_t readlen;
git_zstream zstream;
int result;
size_t out_len;
unsigned char compressed[STREAM_BUFFER_SIZE * 2];
memset(&zstream, 0, sizeof(zstream));
git_deflate_init(&zstream, args->compression_level);
compressed_size = 0;
zstream.next_out = compressed;
zstream.avail_out = sizeof(compressed);
for (;;) {
readlen = read_istream(stream, buf, sizeof(buf));
if (readlen <= 0)
break;
crc = crc32(crc, buf, readlen);
zstream.next_in = buf;
zstream.avail_in = readlen;
result = git_deflate(&zstream, 0);
if (result != Z_OK)
die("deflate error (%d)", result);
out = compressed;
if (!compressed_size)
out += 2;
out_len = zstream.next_out - out;
if (out_len > 0) {
write_or_die(1, out, out_len);
compressed_size += out_len;
zstream.next_out = compressed;
zstream.avail_out = sizeof(compressed);
}
}
close_istream(stream);
if (readlen)
return readlen;
zstream.next_in = buf;
zstream.avail_in = 0;
result = git_deflate(&zstream, Z_FINISH);
if (result != Z_STREAM_END)
die("deflate error (%d)", result);
git_deflate_end(&zstream);
out = compressed;
if (!compressed_size)
out += 2;
out_len = zstream.next_out - out - 4;
write_or_die(1, out, out_len);
compressed_size += out_len;
zip_offset += compressed_size;
write_zip_data_desc(size, compressed_size, crc);
zip_offset += ZIP_DATA_DESC_SIZE;
set_zip_dir_data_desc(&dirent, size, compressed_size, crc);
} else if (compressed_size > 0) {
write_or_die(1, out, compressed_size);
zip_offset += compressed_size;
}
free(deflated);
free(buffer);
memcpy(zip_dir + zip_dir_offset, &dirent, ZIP_DIR_HEADER_SIZE);
zip_dir_offset += ZIP_DIR_HEADER_SIZE;
memcpy(zip_dir + zip_dir_offset, path, pathlen);
zip_dir_offset += pathlen;
memcpy(zip_dir + zip_dir_offset, &extra, ZIP_EXTRA_MTIME_SIZE);
zip_dir_offset += ZIP_EXTRA_MTIME_SIZE;
zip_dir_entries++;
return 0;
}
static void write_zip_trailer(const unsigned char *sha1)
{
struct zip_dir_trailer trailer;
copy_le32(trailer.magic, 0x06054b50);
copy_le16(trailer.disk, 0);
copy_le16(trailer.directory_start_disk, 0);
copy_le16(trailer.entries_on_this_disk, zip_dir_entries);
copy_le16(trailer.entries, zip_dir_entries);
copy_le32(trailer.size, zip_dir_offset);
copy_le32(trailer.offset, zip_offset);
copy_le16(trailer.comment_length, sha1 ? 40 : 0);
write_or_die(1, zip_dir, zip_dir_offset);
write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
if (sha1)
write_or_die(1, sha1_to_hex(sha1), 40);
}
static void dos_time(time_t *time, int *dos_date, int *dos_time)
{
struct tm *t = localtime(time);
*dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
(t->tm_year + 1900 - 1980) * 512;
*dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
}
static int write_zip_archive(const struct archiver *ar,
struct archiver_args *args)
{
int err;
dos_time(&args->time, &zip_date, &zip_time);
zip_dir = xmalloc(ZIP_DIRECTORY_MIN_SIZE);
zip_dir_size = ZIP_DIRECTORY_MIN_SIZE;
err = write_archive_entries(args, write_zip_entry);
if (!err)
write_zip_trailer(args->commit_sha1);
free(zip_dir);
return err;
}
static struct archiver zip_archiver = {
"zip",
write_zip_archive,
ARCHIVER_WANT_COMPRESSION_LEVELS|ARCHIVER_REMOTE
};
void init_zip_archiver(void)
{
register_archiver(&zip_archiver);
}