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git/archive-zip.c
René Scharfe 5ea2c847c5 archive-zip: write uncompressed size into header even with streaming 
We record the uncompressed and compressed sizes and the CRC of streamed
files as zero in the local header of the file.  The actual values are
recorded in an extra data descriptor after the file content, and in the
usual ZIP directory entry at the end of the archive.

While we know the compressed size and the CRC only after we processed
the contents, we actually know the uncompressed size right from the
start.  And for files that we store uncompressed we also already know
their final size.

Do it like InfoZIP's zip and recored the known values, even though they
can be reconstructed using the ZIP directory and the data descriptors
alone.  InfoZIP's unzip worked fine before, but NetBSD's version
actually depends on these fields.

The uncompressed size is already set by sha1_object_info().  We just
need to initialize the compressed size to zero or the uncompressed size
depending on the compression method (0 means storing).  The CRC was
propertly initialized already.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-01-06 11:35:26 -08:00

444 lines
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/*
* Copyright (c) 2006 Rene Scharfe
*/
#include "cache.h"
#include "archive.h"
#include "streaming.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 (8)
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];
};
/*
* 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)
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);
}
#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;
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 (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 = (method == 0) ? size : 0;
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;
}
}
/* make sure we have enough free space in the dictionary */
direntsize = ZIP_DIR_HEADER_SIZE + pathlen;
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, 0);
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);
set_zip_header_data_desc(&header, size, compressed_size, crc);
copy_le16(header.filename_length, pathlen);
copy_le16(header.extra_length, 0);
write_or_die(1, &header, ZIP_LOCAL_HEADER_SIZE);
zip_offset += ZIP_LOCAL_HEADER_SIZE;
write_or_die(1, path, pathlen);
zip_offset += pathlen;
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;
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);
}
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