Revision 3ebbd00cf3c5a7c6f90e2fed8adaf0c5145fb4ac authored by Jim Hill on 31 May 2015, 18:16:45 UTC, committed by Junio C Hamano on 10 August 2015, 19:51:13 UTC
The loop in strbuf_read() uses xread() repeatedly while extending the strbuf until the call returns zero. If the buffer is sufficiently large to begin with, this results in xread() returning the remainder of the file to the end (returning non-zero), the loop extending the strbuf, and then making another call to xread() to have it return zero. By using read_in_full(), we can tell when the read reached the end of file: when it returns less than was requested, it's eof. This way we can avoid an extra iteration that allocates an extra 8kB that is never used. Signed-off-by: Jim Hill <gjthill@gmail.com> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 282616c
archive-zip.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_raw(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_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)
{
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;
} 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;
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;
}
compressed_size = (method == 0) ? size : 0;
} else {
return error("unsupported file mode: 0%o (SHA1: %s)", mode,
sha1_to_hex(sha1));
}
if (buffer && method == 8) {
out = deflated = zlib_deflate_raw(buffer, size,
args->compression_level,
&compressed_size);
if (!out || compressed_size >= size) {
out = buffer;
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);
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_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);
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);
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);
}
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...