1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/other-licenses/snappy/src/snappy-sinksource.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,136 @@
1.4 +// Copyright 2011 Google Inc. All Rights Reserved.
1.5 +//
1.6 +// Redistribution and use in source and binary forms, with or without
1.7 +// modification, are permitted provided that the following conditions are
1.8 +// met:
1.9 +//
1.10 +// * Redistributions of source code must retain the above copyright
1.11 +// notice, this list of conditions and the following disclaimer.
1.12 +// * Redistributions in binary form must reproduce the above
1.13 +// copyright notice, this list of conditions and the following disclaimer
1.14 +// in the documentation and/or other materials provided with the
1.15 +// distribution.
1.16 +// * Neither the name of Google Inc. nor the names of its
1.17 +// contributors may be used to endorse or promote products derived from
1.18 +// this software without specific prior written permission.
1.19 +//
1.20 +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.21 +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.22 +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.23 +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1.24 +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1.25 +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1.26 +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.27 +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.28 +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.29 +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.30 +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.31 +
1.32 +#ifndef UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
1.33 +#define UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
1.34 +
1.35 +#include <stddef.h>
1.36 +
1.37 +
1.38 +namespace snappy {
1.39 +
1.40 +// A Sink is an interface that consumes a sequence of bytes.
1.41 +class Sink {
1.42 + public:
1.43 + Sink() { }
1.44 + virtual ~Sink();
1.45 +
1.46 + // Append "bytes[0,n-1]" to this.
1.47 + virtual void Append(const char* bytes, size_t n) = 0;
1.48 +
1.49 + // Returns a writable buffer of the specified length for appending.
1.50 + // May return a pointer to the caller-owned scratch buffer which
1.51 + // must have at least the indicated length. The returned buffer is
1.52 + // only valid until the next operation on this Sink.
1.53 + //
1.54 + // After writing at most "length" bytes, call Append() with the
1.55 + // pointer returned from this function and the number of bytes
1.56 + // written. Many Append() implementations will avoid copying
1.57 + // bytes if this function returned an internal buffer.
1.58 + //
1.59 + // If a non-scratch buffer is returned, the caller may only pass a
1.60 + // prefix of it to Append(). That is, it is not correct to pass an
1.61 + // interior pointer of the returned array to Append().
1.62 + //
1.63 + // The default implementation always returns the scratch buffer.
1.64 + virtual char* GetAppendBuffer(size_t length, char* scratch);
1.65 +
1.66 + private:
1.67 + // No copying
1.68 + Sink(const Sink&);
1.69 + void operator=(const Sink&);
1.70 +};
1.71 +
1.72 +// A Source is an interface that yields a sequence of bytes
1.73 +class Source {
1.74 + public:
1.75 + Source() { }
1.76 + virtual ~Source();
1.77 +
1.78 + // Return the number of bytes left to read from the source
1.79 + virtual size_t Available() const = 0;
1.80 +
1.81 + // Peek at the next flat region of the source. Does not reposition
1.82 + // the source. The returned region is empty iff Available()==0.
1.83 + //
1.84 + // Returns a pointer to the beginning of the region and store its
1.85 + // length in *len.
1.86 + //
1.87 + // The returned region is valid until the next call to Skip() or
1.88 + // until this object is destroyed, whichever occurs first.
1.89 + //
1.90 + // The returned region may be larger than Available() (for example
1.91 + // if this ByteSource is a view on a substring of a larger source).
1.92 + // The caller is responsible for ensuring that it only reads the
1.93 + // Available() bytes.
1.94 + virtual const char* Peek(size_t* len) = 0;
1.95 +
1.96 + // Skip the next n bytes. Invalidates any buffer returned by
1.97 + // a previous call to Peek().
1.98 + // REQUIRES: Available() >= n
1.99 + virtual void Skip(size_t n) = 0;
1.100 +
1.101 + private:
1.102 + // No copying
1.103 + Source(const Source&);
1.104 + void operator=(const Source&);
1.105 +};
1.106 +
1.107 +// A Source implementation that yields the contents of a flat array
1.108 +class ByteArraySource : public Source {
1.109 + public:
1.110 + ByteArraySource(const char* p, size_t n) : ptr_(p), left_(n) { }
1.111 + virtual ~ByteArraySource();
1.112 + virtual size_t Available() const;
1.113 + virtual const char* Peek(size_t* len);
1.114 + virtual void Skip(size_t n);
1.115 + private:
1.116 + const char* ptr_;
1.117 + size_t left_;
1.118 +};
1.119 +
1.120 +// A Sink implementation that writes to a flat array without any bound checks.
1.121 +class UncheckedByteArraySink : public Sink {
1.122 + public:
1.123 + explicit UncheckedByteArraySink(char* dest) : dest_(dest) { }
1.124 + virtual ~UncheckedByteArraySink();
1.125 + virtual void Append(const char* data, size_t n);
1.126 + virtual char* GetAppendBuffer(size_t len, char* scratch);
1.127 +
1.128 + // Return the current output pointer so that a caller can see how
1.129 + // many bytes were produced.
1.130 + // Note: this is not a Sink method.
1.131 + char* CurrentDestination() const { return dest_; }
1.132 + private:
1.133 + char* dest_;
1.134 +};
1.135 +
1.136 +
1.137 +}
1.138 +
1.139 +#endif // UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
