Improve and expand base58 comments

update comments so doxygen will pick them up
This commit is contained in:
rxl 2014-04-06 22:30:04 -04:00
parent 513412fd73
commit 4e9667b844
1 changed files with 38 additions and 26 deletions

View File

@ -27,17 +27,20 @@
#include <boost/variant/apply_visitor.hpp> #include <boost/variant/apply_visitor.hpp>
#include <boost/variant/static_visitor.hpp> #include <boost/variant/static_visitor.hpp>
/* All alphanumeric characters except for "0", "I", "O", and "l" */
static const char* pszBase58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; static const char* pszBase58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
// Encode a byte sequence as a base58-encoded string /**
* Encode a byte sequence as a base58-encoded string
*/
inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char* pend) inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char* pend)
{ {
CAutoBN_CTX pctx; CAutoBN_CTX pctx;
CBigNum bn58 = 58; CBigNum bn58 = 58;
CBigNum bn0 = 0; CBigNum bn0 = 0;
// Convert big endian data to little endian // Convert big endian data to little endian - the extra zero at the end will
// Extra zero at the end make sure bignum will interpret as a positive number // ensure bignum interprets it as a positive number */
std::vector<unsigned char> vchTmp(pend-pbegin+1, 0); std::vector<unsigned char> vchTmp(pend-pbegin+1, 0);
reverse_copy(pbegin, pend, vchTmp.begin()); reverse_copy(pbegin, pend, vchTmp.begin());
@ -47,8 +50,8 @@ inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char
// Convert bignum to std::string // Convert bignum to std::string
std::string str; std::string str;
// Expected size increase from base58 conversion is approximately 137% // The expected size increase from base58 conversion is approximately 137%,
// use 138% to be safe // but use 138% to be safe
str.reserve((pend - pbegin) * 138 / 100 + 1); str.reserve((pend - pbegin) * 138 / 100 + 1);
CBigNum dv; CBigNum dv;
CBigNum rem; CBigNum rem;
@ -70,14 +73,18 @@ inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char
return str; return str;
} }
// Encode a byte vector as a base58-encoded string /**
* Encode a byte vector as a base58-encoded string
*/
inline std::string EncodeBase58(const std::vector<unsigned char>& vch) inline std::string EncodeBase58(const std::vector<unsigned char>& vch)
{ {
return EncodeBase58(&vch[0], &vch[0] + vch.size()); return EncodeBase58(&vch[0], &vch[0] + vch.size());
} }
// Decode a base58-encoded string psz into byte vector vchRet /**
// returns true if decoding is successful * Decode a base58-encoded string (psz) into a byte vector (vchRet)
* return true if decoding is successful
*/
inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet) inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet)
{ {
CAutoBN_CTX pctx; CAutoBN_CTX pctx;
@ -109,7 +116,7 @@ inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet)
// Get bignum as little endian data // Get bignum as little endian data
std::vector<unsigned char> vchTmp = bn.getvch(); std::vector<unsigned char> vchTmp = bn.getvch();
// Trim off sign byte if present // Trim off the sign byte if present
if (vchTmp.size() >= 2 && vchTmp.end()[-1] == 0 && vchTmp.end()[-2] >= 0x80) if (vchTmp.size() >= 2 && vchTmp.end()[-1] == 0 && vchTmp.end()[-2] >= 0x80)
vchTmp.erase(vchTmp.end()-1); vchTmp.erase(vchTmp.end()-1);
@ -124,17 +131,18 @@ inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet)
return true; return true;
} }
// Decode a base58-encoded string str into byte vector vchRet /**
// returns true if decoding is successful * Decode a base58-encoded string (str) into a byte vector (vchRet)
* return true if decoding is successful
*/
inline bool DecodeBase58(const std::string& str, std::vector<unsigned char>& vchRet) inline bool DecodeBase58(const std::string& str, std::vector<unsigned char>& vchRet)
{ {
return DecodeBase58(str.c_str(), vchRet); return DecodeBase58(str.c_str(), vchRet);
} }
/**
* Encode a byte vector into a base58-encoded string, including checksum
*/
// Encode a byte vector to a base58-encoded string, including checksum
inline std::string EncodeBase58Check(const std::vector<unsigned char>& vchIn) inline std::string EncodeBase58Check(const std::vector<unsigned char>& vchIn)
{ {
// add 4-byte hash check to the end // add 4-byte hash check to the end
@ -144,8 +152,10 @@ inline std::string EncodeBase58Check(const std::vector<unsigned char>& vchIn)
return EncodeBase58(vch); return EncodeBase58(vch);
} }
// Decode a base58-encoded string psz that includes a checksum, into byte vector vchRet /**
// returns true if decoding is successful * Decode a base58-encoded string (psz) that includes a checksum into a byte
* vector (vchRet), return true if decoding is successful
*/
inline bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRet) inline bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRet)
{ {
if (!DecodeBase58(psz, vchRet)) if (!DecodeBase58(psz, vchRet))
@ -155,6 +165,7 @@ inline bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRe
vchRet.clear(); vchRet.clear();
return false; return false;
} }
// re-calculate the checksum, insure it matches the included 4-byte checksum
uint256 hash = Hash(vchRet.begin(), vchRet.end()-4); uint256 hash = Hash(vchRet.begin(), vchRet.end()-4);
if (memcmp(&hash, &vchRet.end()[-4], 4) != 0) if (memcmp(&hash, &vchRet.end()[-4], 4) != 0)
{ {
@ -165,18 +176,18 @@ inline bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRe
return true; return true;
} }
// Decode a base58-encoded string str that includes a checksum, into byte vector vchRet /**
// returns true if decoding is successful * Decode a base58-encoded string (str) that includes a checksum into a byte
* vector (vchRet), return true if decoding is successful
*/
inline bool DecodeBase58Check(const std::string& str, std::vector<unsigned char>& vchRet) inline bool DecodeBase58Check(const std::string& str, std::vector<unsigned char>& vchRet)
{ {
return DecodeBase58Check(str.c_str(), vchRet); return DecodeBase58Check(str.c_str(), vchRet);
} }
/**
* Base class for all base58-encoded data
*/
/** Base class for all base58-encoded data */
class CBase58Data class CBase58Data
{ {
protected: protected:
@ -347,7 +358,9 @@ bool inline CBitcoinAddressVisitor::operator()(const CKeyID &id) const {
bool inline CBitcoinAddressVisitor::operator()(const CScriptID &id) const { return addr->Set(id); } bool inline CBitcoinAddressVisitor::operator()(const CScriptID &id) const { return addr->Set(id); }
bool inline CBitcoinAddressVisitor::operator()(const CNoDestination &id) const { return false; } bool inline CBitcoinAddressVisitor::operator()(const CNoDestination &id) const { return false; }
/** A base58-encoded secret key */ /**
* A base58-encoded secret key
*/
class CBitcoinSecret : public CBase58Data class CBitcoinSecret : public CBase58Data
{ {
public: public:
@ -393,7 +406,6 @@ public:
} }
}; };
template<typename K, int Size, CChainParams::Base58Type Type> class CBitcoinExtKeyBase : public CBase58Data template<typename K, int Size, CChainParams::Base58Type Type> class CBitcoinExtKeyBase : public CBase58Data
{ {
public: public: