bes  Updated for version 3.20.6
BESUncompress3BZ2.cc
1 // BESUncompress3BZ2.cc
2 
3 // This file is part of bes, A C++ back-end server implementation framework
4 // for the OPeNDAP Data Access Protocol.
5 
6 // Copyright (c) 2004-2009 University Corporation for Atmospheric Research
7 // Author: Patrick West <pwest@ucar.edu> and Jose Garcia <jgarcia@ucar.edu>
8 //
9 // This library is free software; you can redistribute it and/or
10 // modify it under the terms of the GNU Lesser General Public
11 // License as published by the Free Software Foundation; either
12 // version 2.1 of the License, or (at your option) any later version.
13 //
14 // This library is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 // Lesser General Public License for more details.
18 //
19 // You should have received a copy of the GNU Lesser General Public
20 // License along with this library; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 //
23 // You can contact University Corporation for Atmospheric Research at
24 // 3080 Center Green Drive, Boulder, CO 80301
25 
26 // (c) COPYRIGHT University Corporation for Atmospheric Research 2004-2005
27 // Please read the full copyright statement in the file COPYRIGHT_UCAR.
28 //
29 // Authors:
30 // pwest Patrick West <pwest@ucar.edu>
31 // jgarcia Jose Garcia <jgarcia@ucar.edu>
32 
33 
34 #include "config.h"
35 
36 #ifdef HAVE_BZLIB_H
37 #include <bzlib.h>
38 #endif
39 
40 #include <cstring>
41 #include <cerrno>
42 #include <sstream>
43 #include <unistd.h>
44 
45 using std::ostringstream;
46 using std::string;
47 
48 #include "BESUncompress3BZ2.h"
49 #include "BESInternalError.h"
50 #include "BESDebug.h"
51 
52 #define CHUNK 4096
53 
54 #if 0
55 static void bz_internal_error(int errcode)
56 {
57  ostringstream strm;
58  strm << "internal error in bz2 library occurred: " << errcode;
59  throw BESInternalError(strm.str(), __FILE__, __LINE__);
60 }
61 #endif
62 
69 void
70 BESUncompress3BZ2::uncompress( const string &src_name, int fd )
71 {
72 #ifndef HAVE_BZLIB_H
73  string err = "Unable to uncompress bz2 files, feature not built. Check config.h in bes directory for HAVE_BZLIB_H flag set to 1";
74  throw BESInternalError( err, __FILE__, __LINE__ );
75 #else
76  FILE *src = fopen( src_name.c_str(), "rb" );
77  if( !src )
78  {
79  char *serr = strerror( errno );
80  string err = "Unable to open the compressed file "
81  + src_name + ": ";
82  if( serr )
83  {
84  err.append( serr );
85  }
86  else
87  {
88  err.append( "unknown error occurred" );
89  }
90  throw BESInternalError( err, __FILE__, __LINE__ );
91  }
92 
93  int bzerror = 0; // any error flags will be stored here
94  int verbosity = 0; // 0 is silent up to 4 which is very verbose
95  int small = 0; // if non zero then memory management is different
96  // unused void *unused = NULL; // any unused bytes would be stored in here
97  // unused int nunused = 0; // the size of the unused buffer
98  char in[CHUNK]; // input buffer used to read uncompressed data in bzRead
99 
100  BZFILE *bsrc = NULL;
101 
102  bsrc = BZ2_bzReadOpen( &bzerror, src, verbosity, small, NULL, 0 );
103  if( bsrc == NULL )
104  {
105  const char *berr = BZ2_bzerror( bsrc, &bzerror );
106  string err = "bzReadOpen failed on " + src_name + ": ";
107  if( berr )
108  {
109  err.append( berr );
110  }
111  else
112  {
113  err.append( "Unknown error" );
114  }
115  fclose( src );
116 
117  throw BESInternalError( err, __FILE__, __LINE__ );
118  }
119 
120  bool done = false;
121  while( !done )
122  {
123  int bytes_read = BZ2_bzRead( &bzerror, bsrc, in, CHUNK );
124  if( bzerror != BZ_OK && bzerror != BZ_STREAM_END )
125  {
126  const char *berr = BZ2_bzerror( bsrc, &bzerror );
127  string err = "bzRead failed on " + src_name + ": ";
128  if( berr )
129  {
130  err.append( berr );
131  }
132  else
133  {
134  err.append( "Unknown error" );
135  }
136 
137  BZ2_bzReadClose( &bzerror, bsrc );
138  fclose( src );
139 
140  throw BESInternalError( err, __FILE__, __LINE__ );
141  }
142  //if( bytes_read == 0 || bzerror == BZ_STREAM_END )
143  if( bzerror == BZ_STREAM_END )
144  {
145  done = true;
146  }
147  int bytes_written = write(fd, in, bytes_read);
148  if( bytes_written < bytes_read )
149  {
150  ostringstream strm;
151  strm << "Error writing uncompressed data: "
152  << "wrote " << bytes_written
153  << " instead of " << bytes_read;
154 
155  BZ2_bzReadClose( &bzerror, bsrc );
156  fclose( src );
157 
158  throw BESInternalError( strm.str(), __FILE__, __LINE__ );
159  }
160  }
161 
162  BZ2_bzReadClose( &bzerror, bsrc );
163  fclose( src );
164 #endif
165 }
166 
BESInternalError
exception thrown if internal error encountered
Definition: BESInternalError.h:43
BESUncompress3BZ2::uncompress
static void uncompress(const std::string &src, int fd)
uncompress a file with the .bz2 file extension
Definition: BESUncompress3BZ2.cc:70