1 /* zip.c -- compress files to the gzip or pkzip format
3 Copyright (C) 1997-1999, 2006-2007, 2009-2016 Free Software Foundation, Inc.
4 Copyright (C) 1992-1993 Jean-loup Gailly
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
26 local ulg crc; /* crc on uncompressed file data */
27 off_t header_bytes; /* number of bytes in gzip header */
29 /* ===========================================================================
31 * IN assertions: the input and output buffers are cleared.
32 * The variables time_stamp and save_orig_name are initialized.
35 int in, out; /* input and output file descriptors */
37 uch flags = 0; /* general purpose bit flags */
38 ush attr = 0; /* ascii/binary flag */
39 ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */
46 /* Write the header to the gzip file. See algorithm.doc for the format */
49 put_byte(GZIP_MAGIC[0]); /* magic header */
50 put_byte(GZIP_MAGIC[1]);
51 put_byte(DEFLATED); /* compression method */
56 put_byte(flags); /* general flags */
57 if (0 < time_stamp.tv_sec && time_stamp.tv_sec <= 0xffffffff)
58 stamp = time_stamp.tv_sec;
61 /* It's intended that time stamp 0 generates this warning,
62 since gzip format reserves 0 for something else. */
63 warning ("file time stamp out of range for gzip format");
68 /* Write deflated file to zip file */
72 ct_init(&attr, &method);
73 lm_init(level, &deflate_flags);
75 put_byte((uch)deflate_flags); /* extra flags */
76 put_byte(OS_CODE); /* OS identifier */
79 char *p = gzip_base_name (ifname); /* Don't save the directory part. */
84 header_bytes = (off_t)outcnt;
90 * (but not on MSDOS -- diet in TSR mode reports an incorrect file size)
92 if (ifile_size != -1L && bytes_in != ifile_size) {
93 fprintf(stderr, "%s: %s: file size changed while zipping\n",
94 program_name, ifname);
98 /* Write the crc and uncompressed size */
100 put_long((ulg)bytes_in);
108 /* ===========================================================================
109 * Read a new buffer from the current input file, perform end-of-line
110 * translation, and update the crc and input file size.
111 * IN assertion: size >= 2 (for end-of-line translation)
113 int file_read(buf, size)
119 Assert(insize == 0, "inbuf not empty");
121 len = read_buffer (ifd, buf, size);
122 if (len == 0) return (int)len;
123 if (len == (unsigned)-1) {
128 crc = updcrc((uch*)buf, len);
129 bytes_in += (off_t)len;