1/* compress-debug.c - compress debug sections
2   Copyright (C) 2010-2017 Free Software Foundation, Inc.
3
4   This file is part of GAS, the GNU Assembler.
5
6   GAS 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)
9   any later version.
10
11   GAS 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.
15
16   You should have received a copy of the GNU General Public License
17   along with GAS; see the file COPYING.  If not, write to the Free
18   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
19   02110-1301, USA.  */
20
21#include "config.h"
22#include <stdio.h>
23#include <zlib.h>
24#include "ansidecl.h"
25#include "compress-debug.h"
26
27/* Initialize the compression engine.  */
28
29struct z_stream_s *
30compress_init (void)
31{
32  static struct z_stream_s strm;
33
34  strm.zalloc = NULL;
35  strm.zfree = NULL;
36  strm.opaque = NULL;
37  deflateInit (&strm, Z_DEFAULT_COMPRESSION);
38  return &strm;
39}
40
41/* Stream the contents of a frag to the compression engine.  Output
42   from the engine goes into the current frag on the obstack.  */
43
44int
45compress_data (struct z_stream_s *strm, const char **next_in,
46	       int *avail_in, char **next_out, int *avail_out)
47{
48  int out_size = 0;
49  int x;
50
51  strm->next_in = (Bytef *) (*next_in);
52  strm->avail_in = *avail_in;
53  strm->next_out = (Bytef *) (*next_out);
54  strm->avail_out = *avail_out;
55
56  x = deflate (strm, Z_NO_FLUSH);
57  if (x != Z_OK)
58    return -1;
59
60  out_size = *avail_out - strm->avail_out;
61  *next_in = (char *) (strm->next_in);
62  *avail_in = strm->avail_in;
63  *next_out = (char *) (strm->next_out);
64  *avail_out = strm->avail_out;
65
66  return out_size;
67}
68
69/* Finish the compression and consume the remaining compressed output.
70   Returns -1 for error, 0 when done, 1 when more output buffer is
71   needed.  */
72
73int
74compress_finish (struct z_stream_s *strm, char **next_out,
75		 int *avail_out, int *out_size)
76{
77  int x;
78
79  strm->avail_in = 0;
80  strm->next_out = (Bytef *) (*next_out);
81  strm->avail_out = *avail_out;
82
83  x = deflate (strm, Z_FINISH);
84
85  *out_size = *avail_out - strm->avail_out;
86  *next_out = (char *) (strm->next_out);
87  *avail_out = strm->avail_out;
88
89  if (x == Z_STREAM_END)
90    {
91      deflateEnd (strm);
92      return 0;
93    }
94  if (strm->avail_out != 0)
95    return -1;
96  return 1;
97}
98