view src/zlib-1.2.7/contrib/iostream/zfstream.cpp @ 83:ae30d91d2ffe

Replace these with versions built using an older toolset (so as to avoid ABI compatibilities when linking on Ubuntu 14.04 for packaging purposes)
author Chris Cannam
date Fri, 07 Feb 2020 11:51:13 +0000
parents e13257ea84a4
children
line wrap: on
line source

#include "zfstream.h"

gzfilebuf::gzfilebuf() :
  file(NULL),
  mode(0),
  own_file_descriptor(0)
{ }

gzfilebuf::~gzfilebuf() {

  sync();
  if ( own_file_descriptor )
    close();

}

gzfilebuf *gzfilebuf::open( const char *name,
                            int io_mode ) {

  if ( is_open() )
    return NULL;

  char char_mode[10];
  char *p = char_mode;

  if ( io_mode & ios::in ) {
    mode = ios::in;
    *p++ = 'r';
  } else if ( io_mode & ios::app ) {
    mode = ios::app;
    *p++ = 'a';
  } else {
    mode = ios::out;
    *p++ = 'w';
  }

  if ( io_mode & ios::binary ) {
    mode |= ios::binary;
    *p++ = 'b';
  }

  // Hard code the compression level
  if ( io_mode & (ios::out|ios::app )) {
    *p++ = '9';
  }

  // Put the end-of-string indicator
  *p = '\0';

  if ( (file = gzopen(name, char_mode)) == NULL )
    return NULL;

  own_file_descriptor = 1;

  return this;

}

gzfilebuf *gzfilebuf::attach( int file_descriptor,
                              int io_mode ) {

  if ( is_open() )
    return NULL;

  char char_mode[10];
  char *p = char_mode;

  if ( io_mode & ios::in ) {
    mode = ios::in;
    *p++ = 'r';
  } else if ( io_mode & ios::app ) {
    mode = ios::app;
    *p++ = 'a';
  } else {
    mode = ios::out;
    *p++ = 'w';
  }

  if ( io_mode & ios::binary ) {
    mode |= ios::binary;
    *p++ = 'b';
  }

  // Hard code the compression level
  if ( io_mode & (ios::out|ios::app )) {
    *p++ = '9';
  }

  // Put the end-of-string indicator
  *p = '\0';

  if ( (file = gzdopen(file_descriptor, char_mode)) == NULL )
    return NULL;

  own_file_descriptor = 0;

  return this;

}

gzfilebuf *gzfilebuf::close() {

  if ( is_open() ) {

    sync();
    gzclose( file );
    file = NULL;

  }

  return this;

}

int gzfilebuf::setcompressionlevel( int comp_level ) {

  return gzsetparams(file, comp_level, -2);

}

int gzfilebuf::setcompressionstrategy( int comp_strategy ) {

  return gzsetparams(file, -2, comp_strategy);

}


streampos gzfilebuf::seekoff( streamoff off, ios::seek_dir dir, int which ) {

  return streampos(EOF);

}

int gzfilebuf::underflow() {

  // If the file hasn't been opened for reading, error.
  if ( !is_open() || !(mode & ios::in) )
    return EOF;

  // if a buffer doesn't exists, allocate one.
  if ( !base() ) {

    if ( (allocate()) == EOF )
      return EOF;
    setp(0,0);

  } else {

    if ( in_avail() )
      return (unsigned char) *gptr();

    if ( out_waiting() ) {
      if ( flushbuf() == EOF )
        return EOF;
    }

  }

  // Attempt to fill the buffer.

  int result = fillbuf();
  if ( result == EOF ) {
    // disable get area
    setg(0,0,0);
    return EOF;
  }

  return (unsigned char) *gptr();

}

int gzfilebuf::overflow( int c ) {

  if ( !is_open() || !(mode & ios::out) )
    return EOF;

  if ( !base() ) {
    if ( allocate() == EOF )
      return EOF;
    setg(0,0,0);
  } else {
    if (in_avail()) {
        return EOF;
    }
    if (out_waiting()) {
      if (flushbuf() == EOF)
        return EOF;
    }
  }

  int bl = blen();
  setp( base(), base() + bl);

  if ( c != EOF ) {

    *pptr() = c;
    pbump(1);

  }

  return 0;

}

int gzfilebuf::sync() {

  if ( !is_open() )
    return EOF;

  if ( out_waiting() )
    return flushbuf();

  return 0;

}

int gzfilebuf::flushbuf() {

  int n;
  char *q;

  q = pbase();
  n = pptr() - q;

  if ( gzwrite( file, q, n) < n )
    return EOF;

  setp(0,0);

  return 0;

}

int gzfilebuf::fillbuf() {

  int required;
  char *p;

  p = base();

  required = blen();

  int t = gzread( file, p, required );

  if ( t <= 0) return EOF;

  setg( base(), base(), base()+t);

  return t;

}

gzfilestream_common::gzfilestream_common() :
  ios( gzfilestream_common::rdbuf() )
{ }

gzfilestream_common::~gzfilestream_common()
{ }

void gzfilestream_common::attach( int fd, int io_mode ) {

  if ( !buffer.attach( fd, io_mode) )
    clear( ios::failbit | ios::badbit );
  else
    clear();

}

void gzfilestream_common::open( const char *name, int io_mode ) {

  if ( !buffer.open( name, io_mode ) )
    clear( ios::failbit | ios::badbit );
  else
    clear();

}

void gzfilestream_common::close() {

  if ( !buffer.close() )
    clear( ios::failbit | ios::badbit );

}

gzfilebuf *gzfilestream_common::rdbuf()
{
  return &buffer;
}

gzifstream::gzifstream() :
  ios( gzfilestream_common::rdbuf() )
{
  clear( ios::badbit );
}

gzifstream::gzifstream( const char *name, int io_mode ) :
  ios( gzfilestream_common::rdbuf() )
{
  gzfilestream_common::open( name, io_mode );
}

gzifstream::gzifstream( int fd, int io_mode ) :
  ios( gzfilestream_common::rdbuf() )
{
  gzfilestream_common::attach( fd, io_mode );
}

gzifstream::~gzifstream() { }

gzofstream::gzofstream() :
  ios( gzfilestream_common::rdbuf() )
{
  clear( ios::badbit );
}

gzofstream::gzofstream( const char *name, int io_mode ) :
  ios( gzfilestream_common::rdbuf() )
{
  gzfilestream_common::open( name, io_mode );
}

gzofstream::gzofstream( int fd, int io_mode ) :
  ios( gzfilestream_common::rdbuf() )
{
  gzfilestream_common::attach( fd, io_mode );
}

gzofstream::~gzofstream() { }