git/archive-zip.c
René Scharfe 200589abcb archive: read short blobs in archive.c::write_archive_entry()
Centralize reading of symlink destinations and the contents of regular
files that are too small to be streamed.  This reduces code duplication
and allows future patches to add support for adding non-tracked files to
archives.  The backends are expected to stream blobs if buffer is NULL.

object_file_to_archive() is only called from archive.c and thus no
longer exported.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-09-19 15:56:05 -07:00

649 lines
17 KiB
C

/*
* Copyright (c) 2006 Rene Scharfe
*/
#include "cache.h"
#include "config.h"
#include "archive.h"
#include "streaming.h"
#include "utf8.h"
#include "object-store.h"
#include "userdiff.h"
#include "xdiff-interface.h"
static int zip_date;
static int zip_time;
/* We only care about the "buf" part here. */
static struct strbuf zip_dir;
static uintmax_t zip_offset;
static uint64_t zip_dir_entries;
static unsigned int max_creator_version;
#define ZIP_STREAM (1 << 3)
#define ZIP_UTF8 (1 << 11)
enum zip_method {
ZIP_METHOD_STORE = 0,
ZIP_METHOD_DEFLATE = 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 zip64_data_desc {
unsigned char magic[4];
unsigned char crc32[4];
unsigned char compressed_size[8];
unsigned char size[8];
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];
};
struct zip64_extra {
unsigned char magic[2];
unsigned char extra_size[2];
unsigned char size[8];
unsigned char compressed_size[8];
unsigned char _end[1];
};
struct zip64_dir_trailer {
unsigned char magic[4];
unsigned char record_size[8];
unsigned char creator_version[2];
unsigned char version[2];
unsigned char disk[4];
unsigned char directory_start_disk[4];
unsigned char entries_on_this_disk[8];
unsigned char entries[8];
unsigned char size[8];
unsigned char offset[8];
unsigned char _end[1];
};
struct zip64_dir_trailer_locator {
unsigned char magic[4];
unsigned char disk[4];
unsigned char offset[8];
unsigned char number_of_disks[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 ZIP64_DATA_DESC_SIZE offsetof(struct zip64_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))
#define ZIP64_EXTRA_SIZE offsetof(struct zip64_extra, _end)
#define ZIP64_EXTRA_PAYLOAD_SIZE \
(ZIP64_EXTRA_SIZE - offsetof(struct zip64_extra, size))
#define ZIP64_DIR_TRAILER_SIZE offsetof(struct zip64_dir_trailer, _end)
#define ZIP64_DIR_TRAILER_RECORD_SIZE \
(ZIP64_DIR_TRAILER_SIZE - \
offsetof(struct zip64_dir_trailer, creator_version))
#define ZIP64_DIR_TRAILER_LOCATOR_SIZE \
offsetof(struct zip64_dir_trailer_locator, _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 copy_le64(unsigned char *dest, uint64_t n)
{
dest[0] = 0xff & n;
dest[1] = 0xff & (n >> 010);
dest[2] = 0xff & (n >> 020);
dest[3] = 0xff & (n >> 030);
dest[4] = 0xff & (n >> 040);
dest[5] = 0xff & (n >> 050);
dest[6] = 0xff & (n >> 060);
dest[7] = 0xff & (n >> 070);
}
static uint64_t clamp_max(uint64_t n, uint64_t max, int *clamped)
{
if (n <= max)
return n;
*clamped = 1;
return max;
}
static void copy_le16_clamp(unsigned char *dest, uint64_t n, int *clamped)
{
copy_le16(dest, clamp_max(n, 0xffff, clamped));
}
static void copy_le32_clamp(unsigned char *dest, uint64_t n, int *clamped)
{
copy_le32(dest, clamp_max(n, 0xffffffff, clamped));
}
static int strbuf_add_le(struct strbuf *sb, size_t size, uintmax_t n)
{
while (size-- > 0) {
strbuf_addch(sb, n & 0xff);
n >>= 8;
}
return -!!n;
}
static uint32_t clamp32(uintmax_t n)
{
const uintmax_t max = 0xffffffff;
return (n < max) ? n : max;
}
static void *zlib_deflate_raw(void *data, unsigned long size,
int compression_level,
unsigned long *compressed_size)
{
git_zstream stream;
unsigned long maxsize;
void *buffer;
int result;
git_deflate_init_raw(&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)
{
if (size >= 0xffffffff || compressed_size >= 0xffffffff) {
struct zip64_data_desc trailer;
copy_le32(trailer.magic, 0x08074b50);
copy_le32(trailer.crc32, crc);
copy_le64(trailer.compressed_size, compressed_size);
copy_le64(trailer.size, size);
write_or_die(1, &trailer, ZIP64_DATA_DESC_SIZE);
zip_offset += ZIP64_DATA_DESC_SIZE;
} else {
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);
zip_offset += ZIP_DATA_DESC_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;
}
}
static int entry_is_binary(struct index_state *istate, const char *path,
const void *buffer, size_t size)
{
struct userdiff_driver *driver = userdiff_find_by_path(istate, path);
if (!driver)
driver = userdiff_find_by_name("default");
if (driver->binary != -1)
return driver->binary;
return buffer_is_binary(buffer, size);
}
#define STREAM_BUFFER_SIZE (1024 * 16)
static int write_zip_entry(struct archiver_args *args,
const struct object_id *oid,
const char *path, size_t pathlen,
unsigned int mode,
void *buffer, unsigned long size)
{
struct zip_local_header header;
uintmax_t offset = zip_offset;
struct zip_extra_mtime extra;
struct zip64_extra extra64;
size_t header_extra_size = ZIP_EXTRA_MTIME_SIZE;
int need_zip64_extra = 0;
unsigned long attr2;
unsigned long compressed_size;
unsigned long crc;
enum zip_method method;
unsigned char *out;
void *deflated = NULL;
struct git_istream *stream = NULL;
unsigned long flags = 0;
int is_binary = -1;
const char *path_without_prefix = path + args->baselen;
unsigned int creator_version = 0;
unsigned int version_needed = 10;
size_t zip_dir_extra_size = ZIP_EXTRA_MTIME_SIZE;
size_t zip64_dir_extra_payload_size = 0;
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, oid_to_hex(oid), path);
}
if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
method = ZIP_METHOD_STORE;
attr2 = 16;
out = NULL;
compressed_size = 0;
} else if (S_ISREG(mode) || S_ISLNK(mode)) {
method = ZIP_METHOD_STORE;
attr2 = S_ISLNK(mode) ? ((mode | 0777) << 16) :
(mode & 0111) ? ((mode) << 16) : 0;
if (S_ISLNK(mode) || (mode & 0111))
creator_version = 0x0317;
if (S_ISREG(mode) && args->compression_level != 0 && size > 0)
method = ZIP_METHOD_DEFLATE;
if (!buffer) {
enum object_type type;
stream = open_istream(args->repo, oid, &type, &size,
NULL);
if (!stream)
return error(_("cannot stream blob %s"),
oid_to_hex(oid));
flags |= ZIP_STREAM;
out = NULL;
} else {
crc = crc32(crc, buffer, size);
is_binary = entry_is_binary(args->repo->index,
path_without_prefix,
buffer, size);
out = buffer;
}
compressed_size = (method == ZIP_METHOD_STORE) ? size : 0;
} else {
return error(_("unsupported file mode: 0%o (SHA1: %s)"), mode,
oid_to_hex(oid));
}
if (creator_version > max_creator_version)
max_creator_version = creator_version;
if (buffer && method == ZIP_METHOD_DEFLATE) {
out = deflated = zlib_deflate_raw(buffer, size,
args->compression_level,
&compressed_size);
if (!out || compressed_size >= size) {
out = buffer;
method = ZIP_METHOD_STORE;
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);
if (size > 0xffffffff || compressed_size > 0xffffffff)
need_zip64_extra = 1;
if (stream && size > 0x7fffffff)
need_zip64_extra = 1;
if (need_zip64_extra)
version_needed = 45;
copy_le32(header.magic, 0x04034b50);
copy_le16(header.version, version_needed);
copy_le16(header.flags, flags);
copy_le16(header.compression_method, method);
copy_le16(header.mtime, zip_time);
copy_le16(header.mdate, zip_date);
if (need_zip64_extra) {
set_zip_header_data_desc(&header, 0xffffffff, 0xffffffff, crc);
header_extra_size += ZIP64_EXTRA_SIZE;
} else {
set_zip_header_data_desc(&header, size, compressed_size, crc);
}
copy_le16(header.filename_length, pathlen);
copy_le16(header.extra_length, header_extra_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 (need_zip64_extra) {
copy_le16(extra64.magic, 0x0001);
copy_le16(extra64.extra_size, ZIP64_EXTRA_PAYLOAD_SIZE);
copy_le64(extra64.size, size);
copy_le64(extra64.compressed_size, compressed_size);
write_or_die(1, &extra64, ZIP64_EXTRA_SIZE);
zip_offset += ZIP64_EXTRA_SIZE;
}
if (stream && method == ZIP_METHOD_STORE) {
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);
if (is_binary == -1)
is_binary = entry_is_binary(args->repo->index,
path_without_prefix,
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);
} else if (stream && method == ZIP_METHOD_DEFLATE) {
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];
git_deflate_init_raw(&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);
if (is_binary == -1)
is_binary = entry_is_binary(args->repo->index,
path_without_prefix,
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_len = zstream.next_out - compressed;
if (out_len > 0) {
write_or_die(1, compressed, 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_len = zstream.next_out - compressed;
write_or_die(1, compressed, out_len);
compressed_size += out_len;
zip_offset += compressed_size;
write_zip_data_desc(size, compressed_size, crc);
} else if (compressed_size > 0) {
write_or_die(1, out, compressed_size);
zip_offset += compressed_size;
}
free(deflated);
if (compressed_size > 0xffffffff || size > 0xffffffff ||
offset > 0xffffffff) {
if (compressed_size >= 0xffffffff)
zip64_dir_extra_payload_size += 8;
if (size >= 0xffffffff)
zip64_dir_extra_payload_size += 8;
if (offset >= 0xffffffff)
zip64_dir_extra_payload_size += 8;
zip_dir_extra_size += 2 + 2 + zip64_dir_extra_payload_size;
}
strbuf_add_le(&zip_dir, 4, 0x02014b50); /* magic */
strbuf_add_le(&zip_dir, 2, creator_version);
strbuf_add_le(&zip_dir, 2, version_needed);
strbuf_add_le(&zip_dir, 2, flags);
strbuf_add_le(&zip_dir, 2, method);
strbuf_add_le(&zip_dir, 2, zip_time);
strbuf_add_le(&zip_dir, 2, zip_date);
strbuf_add_le(&zip_dir, 4, crc);
strbuf_add_le(&zip_dir, 4, clamp32(compressed_size));
strbuf_add_le(&zip_dir, 4, clamp32(size));
strbuf_add_le(&zip_dir, 2, pathlen);
strbuf_add_le(&zip_dir, 2, zip_dir_extra_size);
strbuf_add_le(&zip_dir, 2, 0); /* comment length */
strbuf_add_le(&zip_dir, 2, 0); /* disk */
strbuf_add_le(&zip_dir, 2, !is_binary);
strbuf_add_le(&zip_dir, 4, attr2);
strbuf_add_le(&zip_dir, 4, clamp32(offset));
strbuf_add(&zip_dir, path, pathlen);
strbuf_add(&zip_dir, &extra, ZIP_EXTRA_MTIME_SIZE);
if (zip64_dir_extra_payload_size) {
strbuf_add_le(&zip_dir, 2, 0x0001); /* magic */
strbuf_add_le(&zip_dir, 2, zip64_dir_extra_payload_size);
if (size >= 0xffffffff)
strbuf_add_le(&zip_dir, 8, size);
if (compressed_size >= 0xffffffff)
strbuf_add_le(&zip_dir, 8, compressed_size);
if (offset >= 0xffffffff)
strbuf_add_le(&zip_dir, 8, offset);
}
zip_dir_entries++;
return 0;
}
static void write_zip64_trailer(void)
{
struct zip64_dir_trailer trailer64;
struct zip64_dir_trailer_locator locator64;
copy_le32(trailer64.magic, 0x06064b50);
copy_le64(trailer64.record_size, ZIP64_DIR_TRAILER_RECORD_SIZE);
copy_le16(trailer64.creator_version, max_creator_version);
copy_le16(trailer64.version, 45);
copy_le32(trailer64.disk, 0);
copy_le32(trailer64.directory_start_disk, 0);
copy_le64(trailer64.entries_on_this_disk, zip_dir_entries);
copy_le64(trailer64.entries, zip_dir_entries);
copy_le64(trailer64.size, zip_dir.len);
copy_le64(trailer64.offset, zip_offset);
copy_le32(locator64.magic, 0x07064b50);
copy_le32(locator64.disk, 0);
copy_le64(locator64.offset, zip_offset + zip_dir.len);
copy_le32(locator64.number_of_disks, 1);
write_or_die(1, &trailer64, ZIP64_DIR_TRAILER_SIZE);
write_or_die(1, &locator64, ZIP64_DIR_TRAILER_LOCATOR_SIZE);
}
static void write_zip_trailer(const struct object_id *oid)
{
struct zip_dir_trailer trailer;
int clamped = 0;
copy_le32(trailer.magic, 0x06054b50);
copy_le16(trailer.disk, 0);
copy_le16(trailer.directory_start_disk, 0);
copy_le16_clamp(trailer.entries_on_this_disk, zip_dir_entries,
&clamped);
copy_le16_clamp(trailer.entries, zip_dir_entries, &clamped);
copy_le32(trailer.size, zip_dir.len);
copy_le32_clamp(trailer.offset, zip_offset, &clamped);
copy_le16(trailer.comment_length, oid ? the_hash_algo->hexsz : 0);
write_or_die(1, zip_dir.buf, zip_dir.len);
if (clamped)
write_zip64_trailer();
write_or_die(1, &trailer, ZIP_DIR_TRAILER_SIZE);
if (oid)
write_or_die(1, oid_to_hex(oid), the_hash_algo->hexsz);
}
static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
{
time_t time;
struct tm tm;
if (date_overflows(*timestamp))
die(_("timestamp too large for this system: %"PRItime),
*timestamp);
time = (time_t)*timestamp;
localtime_r(&time, &tm);
*timestamp = time;
*dos_date = tm.tm_mday + (tm.tm_mon + 1) * 32 +
(tm.tm_year + 1900 - 1980) * 512;
*dos_time = tm.tm_sec / 2 + tm.tm_min * 32 + tm.tm_hour * 2048;
}
static int archive_zip_config(const char *var, const char *value, void *data)
{
return userdiff_config(var, value);
}
static int write_zip_archive(const struct archiver *ar,
struct archiver_args *args)
{
int err;
git_config(archive_zip_config, NULL);
dos_time(&args->time, &zip_date, &zip_time);
strbuf_init(&zip_dir, 0);
err = write_archive_entries(args, write_zip_entry);
if (!err)
write_zip_trailer(args->commit_oid);
strbuf_release(&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);
}