1 /*
2  * THIS FILE IS NOT IDENTICAL TO THE ORIGINAL
3  * FROM THE BZIP2 DISTRIBUTION.
4  *
5  * It has been modified, mainly to break the library
6  * into smaller pieces.
7  *
8  * Russ Cox
9  * rsc@plan9.bell-labs.com
10  * July 2000
11  */
12 
13 /*-------------------------------------------------------------*/
14 /*--- Library top-level functions.                          ---*/
15 /*---                                               bzlib.c ---*/
16 /*-------------------------------------------------------------*/
17 
18 /*--
19   This file is a part of bzip2 and/or libbzip2, a program and
20   library for lossless, block-sorting data compression.
21 
22   Copyright (C) 1996-2000 Julian R Seward.  All rights reserved.
23 
24   Redistribution and use in source and binary forms, with or without
25   modification, are permitted provided that the following conditions
26   are met:
27 
28   1. Redistributions of source code must retain the above copyright
29      notice, this list of conditions and the following disclaimer.
30 
31   2. The origin of this software must not be misrepresented; you must 
32      not claim that you wrote the original software.  If you use this 
33      software in a product, an acknowledgment in the product 
34      documentation would be appreciated but is not required.
35 
36   3. Altered source versions must be plainly marked as such, and must
37      not be misrepresented as being the original software.
38 
39   4. The name of the author may not be used to endorse or promote 
40      products derived from this software without specific prior written 
41      permission.
42 
43   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
44   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
45   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
47   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
49   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
50   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
51   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
52   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
53   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54 
55   Julian Seward, Cambridge, UK.
56   jseward@acm.org
57   bzip2/libbzip2 version 1.0 of 21 March 2000
58 
59   This program is based on (at least) the work of:
60      Mike Burrows
61      David Wheeler
62      Peter Fenwick
63      Alistair Moffat
64      Radford Neal
65      Ian H. Witten
66      Robert Sedgewick
67      Jon L. Bentley
68 
69   For more information on these sources, see the manual.
70 --*/
71 
72 /*--
73    CHANGES
74    ~~~~~~~
75    0.9.0 -- original version.
76 
77    0.9.0a/b -- no changes in this file.
78 
79    0.9.0c
80       * made zero-length BZ_FLUSH work correctly in bzCompress().
81       * fixed bzWrite/bzRead to ignore zero-length requests.
82       * fixed bzread to correctly handle read requests after EOF.
83       * wrong parameter order in call to bzDecompressInit in
84         bzBuffToBuffDecompress.  Fixed.
85 --*/
86 
87 #include "os.h"
88 #include "bzlib.h"
89 #include "bzlib_private.h"
90 
91 /*---------------------------------------------------*/
92 int BZ_API(BZ2_bzBuffToBuffCompress) 
93                          ( char*         dest, 
94                            unsigned int* destLen,
95                            char*         source, 
96                            unsigned int  sourceLen,
97                            int           blockSize100k, 
98                            int           verbosity, 
99                            int           workFactor )
100 {
101    bz_stream strm;
102    int ret;
103 
104    if (dest == NULL || destLen == NULL || 
105        source == NULL ||
106        blockSize100k < 1 || blockSize100k > 9 ||
107        verbosity < 0 || verbosity > 4 ||
108        workFactor < 0 || workFactor > 250) 
109       return BZ_PARAM_ERROR;
110 
111    if (workFactor == 0) workFactor = 30;
112    strm.bzalloc = NULL;
113    strm.bzfree = NULL;
114    strm.opaque = NULL;
115    ret = BZ2_bzCompressInit ( &strm, blockSize100k, 
116                               verbosity, workFactor );
117    if (ret != BZ_OK) return ret;
118 
119    strm.next_in = source;
120    strm.next_out = dest;
121    strm.avail_in = sourceLen;
122    strm.avail_out = *destLen;
123 
124    ret = BZ2_bzCompress ( &strm, BZ_FINISH );
125    if (ret == BZ_FINISH_OK) goto output_overflow;
126    if (ret != BZ_STREAM_END) goto errhandler;
127 
128    /* normal termination */
129    *destLen -= strm.avail_out;   
130    BZ2_bzCompressEnd ( &strm );
131    return BZ_OK;
132 
133    output_overflow:
134    BZ2_bzCompressEnd ( &strm );
135    return BZ_OUTBUFF_FULL;
136 
137    errhandler:
138    BZ2_bzCompressEnd ( &strm );
139    return ret;
140 }
141