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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2013 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_STREAMS_H
#define BITCOIN_STREAMS_H
#include "allocators.h"
#include "serialize.h"
#include <algorithm>
#include <assert.h>
#include <ios>
#include <limits>
#include <map>
#include <set>
#include <stdint.h>
#include <string>
#include <string.h>
#include <utility>
#include <vector>
/** Double ended buffer combining vector and stream-like interfaces.
*
* >> and << read and write unformatted data using the above serialization templates.
* Fills with data in linear time; some stringstream implementations take N^2 time.
*/
class CDataStream
{
protected:
typedef CSerializeData vector_type;
vector_type vch;
unsigned int nReadPos;
public:
int nType;
int nVersion;
typedef vector_type::allocator_type allocator_type;
typedef vector_type::size_type size_type;
typedef vector_type::difference_type difference_type;
typedef vector_type::reference reference;
typedef vector_type::const_reference const_reference;
typedef vector_type::value_type value_type;
typedef vector_type::iterator iterator;
typedef vector_type::const_iterator const_iterator;
typedef vector_type::reverse_iterator reverse_iterator;
explicit CDataStream(int nTypeIn, int nVersionIn)
{
Init(nTypeIn, nVersionIn);
}
CDataStream(const_iterator pbegin, const_iterator pend, int nTypeIn, int nVersionIn) : vch(pbegin, pend)
{
Init(nTypeIn, nVersionIn);
}
#if !defined(_MSC_VER) || _MSC_VER >= 1300
CDataStream(const char* pbegin, const char* pend, int nTypeIn, int nVersionIn) : vch(pbegin, pend)
{
Init(nTypeIn, nVersionIn);
}
#endif
CDataStream(const vector_type& vchIn, int nTypeIn, int nVersionIn) : vch(vchIn.begin(), vchIn.end())
{
Init(nTypeIn, nVersionIn);
}
CDataStream(const std::vector<char>& vchIn, int nTypeIn, int nVersionIn) : vch(vchIn.begin(), vchIn.end())
{
Init(nTypeIn, nVersionIn);
}
CDataStream(const std::vector<unsigned char>& vchIn, int nTypeIn, int nVersionIn) : vch(vchIn.begin(), vchIn.end())
{
Init(nTypeIn, nVersionIn);
}
void Init(int nTypeIn, int nVersionIn)
{
nReadPos = 0;
nType = nTypeIn;
nVersion = nVersionIn;
}
CDataStream& operator+=(const CDataStream& b)
{
vch.insert(vch.end(), b.begin(), b.end());
return *this;
}
friend CDataStream operator+(const CDataStream& a, const CDataStream& b)
{
CDataStream ret = a;
ret += b;
return (ret);
}
std::string str() const
{
return (std::string(begin(), end()));
}
//
// Vector subset
//
const_iterator begin() const { return vch.begin() + nReadPos; }
iterator begin() { return vch.begin() + nReadPos; }
const_iterator end() const { return vch.end(); }
iterator end() { return vch.end(); }
size_type size() const { return vch.size() - nReadPos; }
bool empty() const { return vch.size() == nReadPos; }
void resize(size_type n, value_type c=0) { vch.resize(n + nReadPos, c); }
void reserve(size_type n) { vch.reserve(n + nReadPos); }
const_reference operator[](size_type pos) const { return vch[pos + nReadPos]; }
reference operator[](size_type pos) { return vch[pos + nReadPos]; }
void clear() { vch.clear(); nReadPos = 0; }
iterator insert(iterator it, const char& x=char()) { return vch.insert(it, x); }
void insert(iterator it, size_type n, const char& x) { vch.insert(it, n, x); }
void insert(iterator it, std::vector<char>::const_iterator first, std::vector<char>::const_iterator last)
{
assert(last - first >= 0);
if (it == vch.begin() + nReadPos && (unsigned int)(last - first) <= nReadPos)
{
// special case for inserting at the front when there's room
nReadPos -= (last - first);
memcpy(&vch[nReadPos], &first[0], last - first);
}
else
vch.insert(it, first, last);
}
#if !defined(_MSC_VER) || _MSC_VER >= 1300
void insert(iterator it, const char* first, const char* last)
{
assert(last - first >= 0);
if (it == vch.begin() + nReadPos && (unsigned int)(last - first) <= nReadPos)
{
// special case for inserting at the front when there's room
nReadPos -= (last - first);
memcpy(&vch[nReadPos], &first[0], last - first);
}
else
vch.insert(it, first, last);
}
#endif
iterator erase(iterator it)
{
if (it == vch.begin() + nReadPos)
{
// special case for erasing from the front
if (++nReadPos >= vch.size())
{
// whenever we reach the end, we take the opportunity to clear the buffer
nReadPos = 0;
return vch.erase(vch.begin(), vch.end());
}
return vch.begin() + nReadPos;
}
else
return vch.erase(it);
}
iterator erase(iterator first, iterator last)
{
if (first == vch.begin() + nReadPos)
{
// special case for erasing from the front
if (last == vch.end())
{
nReadPos = 0;
return vch.erase(vch.begin(), vch.end());
}
else
{
nReadPos = (last - vch.begin());
return last;
}
}
else
return vch.erase(first, last);
}
inline void Compact()
{
vch.erase(vch.begin(), vch.begin() + nReadPos);
nReadPos = 0;
}
bool Rewind(size_type n)
{
// Rewind by n characters if the buffer hasn't been compacted yet
if (n > nReadPos)
return false;
nReadPos -= n;
return true;
}
//
// Stream subset
//
bool eof() const { return size() == 0; }
CDataStream* rdbuf() { return this; }
int in_avail() { return size(); }
void SetType(int n) { nType = n; }
int GetType() { return nType; }
void SetVersion(int n) { nVersion = n; }
int GetVersion() { return nVersion; }
void ReadVersion() { *this >> nVersion; }
void WriteVersion() { *this << nVersion; }
CDataStream& read(char* pch, size_t nSize)
{
// Read from the beginning of the buffer
unsigned int nReadPosNext = nReadPos + nSize;
if (nReadPosNext >= vch.size())
{
if (nReadPosNext > vch.size())
{
throw std::ios_base::failure("CDataStream::read() : end of data");
}
memcpy(pch, &vch[nReadPos], nSize);
nReadPos = 0;
vch.clear();
return (*this);
}
memcpy(pch, &vch[nReadPos], nSize);
nReadPos = nReadPosNext;
return (*this);
}
CDataStream& ignore(int nSize)
{
// Ignore from the beginning of the buffer
assert(nSize >= 0);
unsigned int nReadPosNext = nReadPos + nSize;
if (nReadPosNext >= vch.size())
{
if (nReadPosNext > vch.size())
throw std::ios_base::failure("CDataStream::ignore() : end of data");
nReadPos = 0;
vch.clear();
return (*this);
}
nReadPos = nReadPosNext;
return (*this);
}
CDataStream& write(const char* pch, size_t nSize)
{
// Write to the end of the buffer
vch.insert(vch.end(), pch, pch + nSize);
return (*this);
}
template<typename Stream>
void Serialize(Stream& s, int nType, int nVersion) const
{
// Special case: stream << stream concatenates like stream += stream
if (!vch.empty())
s.write((char*)&vch[0], vch.size() * sizeof(vch[0]));
}
template<typename T>
unsigned int GetSerializeSize(const T& obj)
{
// Tells the size of the object if serialized to this stream
return ::GetSerializeSize(obj, nType, nVersion);
}
template<typename T>
CDataStream& operator<<(const T& obj)
{
// Serialize to this stream
::Serialize(*this, obj, nType, nVersion);
return (*this);
}
template<typename T>
CDataStream& operator>>(T& obj)
{
// Unserialize from this stream
::Unserialize(*this, obj, nType, nVersion);
return (*this);
}
void GetAndClear(CSerializeData &data) {
data.insert(data.end(), begin(), end());
clear();
}
};
/** Non-refcounted RAII wrapper for FILE*
*
* Will automatically close the file when it goes out of scope if not null.
* If you're returning the file pointer, return file.release().
* If you need to close the file early, use file.fclose() instead of fclose(file).
*/
class CAutoFile
{
private:
// Disallow copies
CAutoFile(const CAutoFile&);
CAutoFile& operator=(const CAutoFile&);
int nType;
int nVersion;
FILE* file;
public:
CAutoFile(FILE* filenew, int nTypeIn, int nVersionIn)
{
file = filenew;
nType = nTypeIn;
nVersion = nVersionIn;
}
~CAutoFile()
{
fclose();
}
void fclose()
{
if (file) {
::fclose(file);
file = NULL;
}
}
/** Get wrapped FILE* with transfer of ownership.
* @note This will invalidate the CAutoFile object, and makes it the responsibility of the caller
* of this function to clean up the returned FILE*.
*/
FILE* release() { FILE* ret = file; file = NULL; return ret; }
/** Get wrapped FILE* without transfer of ownership.
* @note Ownership of the FILE* will remain with this class. Use this only if the scope of the
* CAutoFile outlives use of the passed pointer.
*/
FILE* Get() const { return file; }
/** Return true if the wrapped FILE* is NULL, false otherwise.
*/
bool IsNull() const { return (file == NULL); }
//
// Stream subset
//
void SetType(int n) { nType = n; }
int GetType() { return nType; }
void SetVersion(int n) { nVersion = n; }
int GetVersion() { return nVersion; }
void ReadVersion() { *this >> nVersion; }
void WriteVersion() { *this << nVersion; }
CAutoFile& read(char* pch, size_t nSize)
{
if (!file)
throw std::ios_base::failure("CAutoFile::read : file handle is NULL");
if (fread(pch, 1, nSize, file) != nSize)
throw std::ios_base::failure(feof(file) ? "CAutoFile::read : end of file" : "CAutoFile::read : fread failed");
return (*this);
}
CAutoFile& write(const char* pch, size_t nSize)
{
if (!file)
throw std::ios_base::failure("CAutoFile::write : file handle is NULL");
if (fwrite(pch, 1, nSize, file) != nSize)
throw std::ios_base::failure("CAutoFile::write : write failed");
return (*this);
}
template<typename T>
unsigned int GetSerializeSize(const T& obj)
{
// Tells the size of the object if serialized to this stream
return ::GetSerializeSize(obj, nType, nVersion);
}
template<typename T>
CAutoFile& operator<<(const T& obj)
{
// Serialize to this stream
if (!file)
throw std::ios_base::failure("CAutoFile::operator<< : file handle is NULL");
::Serialize(*this, obj, nType, nVersion);
return (*this);
}
template<typename T>
CAutoFile& operator>>(T& obj)
{
// Unserialize from this stream
if (!file)
throw std::ios_base::failure("CAutoFile::operator>> : file handle is NULL");
::Unserialize(*this, obj, nType, nVersion);
return (*this);
}
};
/** Non-refcounted RAII wrapper around a FILE* that implements a ring buffer to
* deserialize from. It guarantees the ability to rewind a given number of bytes.
*
* Will automatically close the file when it goes out of scope if not null.
* If you need to close the file early, use file.fclose() instead of fclose(file).
*/
class CBufferedFile
{
private:
// Disallow copies
CBufferedFile(const CBufferedFile&);
CBufferedFile& operator=(const CBufferedFile&);
int nType;
int nVersion;
FILE *src; // source file
uint64_t nSrcPos; // how many bytes have been read from source
uint64_t nReadPos; // how many bytes have been read from this
uint64_t nReadLimit; // up to which position we're allowed to read
uint64_t nRewind; // how many bytes we guarantee to rewind
std::vector<char> vchBuf; // the buffer
protected:
// read data from the source to fill the buffer
bool Fill() {
unsigned int pos = nSrcPos % vchBuf.size();
unsigned int readNow = vchBuf.size() - pos;
unsigned int nAvail = vchBuf.size() - (nSrcPos - nReadPos) - nRewind;
if (nAvail < readNow)
readNow = nAvail;
if (readNow == 0)
return false;
size_t read = fread((void*)&vchBuf[pos], 1, readNow, src);
if (read == 0) {
throw std::ios_base::failure(feof(src) ? "CBufferedFile::Fill : end of file" : "CBufferedFile::Fill : fread failed");
} else {
nSrcPos += read;
return true;
}
}
public:
CBufferedFile(FILE *fileIn, uint64_t nBufSize, uint64_t nRewindIn, int nTypeIn, int nVersionIn) :
nSrcPos(0), nReadPos(0), nReadLimit((uint64_t)(-1)), nRewind(nRewindIn), vchBuf(nBufSize, 0)
{
src = fileIn;
nType = nTypeIn;
nVersion = nVersionIn;
}
~CBufferedFile()
{
fclose();
}
void fclose()
{
if (src) {
::fclose(src);
src = NULL;
}
}
// check whether we're at the end of the source file
bool eof() const {
return nReadPos == nSrcPos && feof(src);
}
// read a number of bytes
CBufferedFile& read(char *pch, size_t nSize) {
if (nSize + nReadPos > nReadLimit)
throw std::ios_base::failure("Read attempted past buffer limit");
if (nSize + nRewind > vchBuf.size())
throw std::ios_base::failure("Read larger than buffer size");
while (nSize > 0) {
if (nReadPos == nSrcPos)
Fill();
unsigned int pos = nReadPos % vchBuf.size();
size_t nNow = nSize;
if (nNow + pos > vchBuf.size())
nNow = vchBuf.size() - pos;
if (nNow + nReadPos > nSrcPos)
nNow = nSrcPos - nReadPos;
memcpy(pch, &vchBuf[pos], nNow);
nReadPos += nNow;
pch += nNow;
nSize -= nNow;
}
return (*this);
}
// return the current reading position
uint64_t GetPos() {
return nReadPos;
}
// rewind to a given reading position
bool SetPos(uint64_t nPos) {
nReadPos = nPos;
if (nReadPos + nRewind < nSrcPos) {
nReadPos = nSrcPos - nRewind;
return false;
} else if (nReadPos > nSrcPos) {
nReadPos = nSrcPos;
return false;
} else {
return true;
}
}
bool Seek(uint64_t nPos) {
long nLongPos = nPos;
if (nPos != (uint64_t)nLongPos)
return false;
if (fseek(src, nLongPos, SEEK_SET))
return false;
nLongPos = ftell(src);
nSrcPos = nLongPos;
nReadPos = nLongPos;
return true;
}
// prevent reading beyond a certain position
// no argument removes the limit
bool SetLimit(uint64_t nPos = (uint64_t)(-1)) {
if (nPos < nReadPos)
return false;
nReadLimit = nPos;
return true;
}
template<typename T>
CBufferedFile& operator>>(T& obj) {
// Unserialize from this stream
::Unserialize(*this, obj, nType, nVersion);
return (*this);
}
// search for a given byte in the stream, and remain positioned on it
void FindByte(char ch) {
while (true) {
if (nReadPos == nSrcPos)
Fill();
if (vchBuf[nReadPos % vchBuf.size()] == ch)
break;
nReadPos++;
}
}
};
#endif // BITCOIN_STREAMS_H