1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2022 Klara, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 /* This file is #included by gzip.c */
29
30 static off_t
unzstd(int in,int out,char * pre,size_t prelen,off_t * bytes_in)31 unzstd(int in, int out, char *pre, size_t prelen, off_t *bytes_in)
32 {
33 static char *ibuf, *obuf;
34 ZSTD_inBuffer zib;
35 ZSTD_outBuffer zob;
36 ZSTD_DCtx *zds;
37 ssize_t res;
38 size_t zres;
39 size_t bytes_out = 0;
40 int eof = 0;
41
42 if (ibuf == NULL)
43 ibuf = malloc(BUFLEN);
44 if (obuf == NULL)
45 obuf = malloc(BUFLEN);
46 if (ibuf == NULL || obuf == NULL)
47 maybe_err("malloc");
48
49 zds = ZSTD_createDStream();
50 ZSTD_initDStream(zds);
51
52 zib.src = pre;
53 zib.size = prelen;
54 zib.pos = 0;
55 if (bytes_in != NULL)
56 *bytes_in = prelen;
57 zob.dst = obuf;
58 zob.size = BUFLEN;
59 zob.pos = 0;
60
61 while (!eof) {
62 if (zib.pos >= zib.size) {
63 res = read(in, ibuf, BUFLEN);
64 if (res < 0)
65 maybe_err("read");
66 if (res == 0)
67 eof = 1;
68 infile_newdata(res);
69 zib.src = ibuf;
70 zib.size = res;
71 zib.pos = 0;
72 if (bytes_in != NULL)
73 *bytes_in += res;
74 }
75 zres = ZSTD_decompressStream(zds, &zob, &zib);
76 if (ZSTD_isError(zres)) {
77 maybe_errx("%s", ZSTD_getErrorName(zres));
78 }
79 if (zob.pos > 0) {
80 res = write(out, obuf, zob.pos);
81 if (res < 0)
82 maybe_err("write");
83 zob.pos = 0;
84 bytes_out += res;
85 }
86 }
87 ZSTD_freeDStream(zds);
88 return (bytes_out);
89 }
90