stasis-bLSM/StringUtils.h
sears d016498f8d initial import; removed cruft from mert's tarball, tweaked make's clean targets
git-svn-id: svn+ssh://svn.corp.yahoo.com/yahoo/yrl/labs/pnuts/code/logstore@520 8dad8b1f-cf64-0410-95b6-bcf113ffbcfe
2010-01-23 02:13:59 +00:00

345 lines
11 KiB
C++

/* $Id: StringUtils.h,v 1.17 2009/03/25 20:32:51 dlomax Exp $ */
/* Copyright (C) 2008 Yahoo! Inc. All Rights Reserved. */
#ifndef __STRING_UTIL_H
#define __STRING_UTIL_H
#include <iostream>
#include <iomanip>
#include <sstream>
#include "FwCode.h"
/**
* Container for static string manipulation utilities.
*/
class StringUtils
{
public:
/**
* Our replacement for yax_getroot(). Allows our code to have a different
* root than components we use or link with. Is nice for unit testing.
* @return Copy of the value in a std::string
*/
static std::string getDhtRoot();
/**
* Parse a tablet name into left and right limits.
* @return true if parsing successful, false if incorrect format
*/
static bool parseTabletName(const std::string& tablet, std::string& leftLimit,
std::string& rightLimit);
/**
* Construct a tablet name from left and right limits.
*/
static void buildTabletName(const std::string& leftLimit,
const std::string& rightLimit,
std::string& tablet);
/**
* General purpose method to assemble a full path name, using
* getDhtRoot() so that
* the root will be configurable. DO NOT supply "/home/y" in path1.
*/
static std::string makePath(const std::string& path1 = "",
const std::string& path2 = "",
const std::string& path3 = "",
const std::string& path4 = "",
const std::string& path5 = "",
const std::string& path6 = "");
/**
* Append additional paths to an existing one - does not prepend ROOT.
*/
static void appendPath(std::string& base_path, const std::string& path2 = "",
const std::string& path3 = "",
const std::string& path4 = "");
/**
* Construct a topic name from a table/tablet.
*
* @return the topic name
*/
static std::string buildTopicName(const std::string& table,
const std::string& tablet);
/**
* Construct a topic name from a table/tablet.
* @param topic Is filled with the topic name.
*/
static void buildTopicName(const std::string& table,
const std::string& tablet,
std::string &topic);
/**
* Parses <code>topic</code> into table and tablet portions.
*
* @param table Filled with the table name.
* @param tablet Filled with the tablet name.
* @param true if the parsing succeeded, false if not.
*/
static bool parseTopicName(const std::string& topic,
std::string& table,
std::string &tablet);
/**
* Only for use in log statements - this is slow. Produce a printable
* string where binary (<32) characters are hex encoded, but all others
* are left alone.
*
* @param str string to encode
* @param len length of string
* @return encoded string.
*/
static std::string toPrintable(const char *str, size_t len);
/**
* Convert a formatted hex string back into its original
* 64-bit value
*
* @param value the hex-encoded string
* @param out the value
* @return FwCode::FwOk on success, FwCode::BadHexString on parse failure
*/
static FwCode::ResponseCode
convertHexStringToUI64(const std::string& value, uint64_t& out);
/**
* Convert a formatted hex string back into its original
* 32-bit value
*
* @param value the hex-encoded string
* @param out the value
* @return FwCode::FwOk on success, FwCode::BadHexString on parse failure
*/
static FwCode::ResponseCode
convertHexStringToUI32(const std::string& value, uint32_t& out);
/**
* Standard means for formatting a 0x prefixed hex string from a
* 64-bit unsigned value. Will produce upper-case letters. Will
* pad with zeros at the beginning to fill out 16 hex chars.
*
* @param the value to format
* @return the formatted value, like "0xDEADBEEF00000000"
*/
static std::string convertUI64ToHexString( uint64_t val );
/**
* Standard means for formatting a 0x prefixed hex string from a
* 32-bit unsigned value. Will produce upper-case letters. Will
* pad with zeros at the beginning to fill out 8 hex chars.
*
* @param the value to format
* @return the formatted value, like "0xDEADBEEF"
*/
static std::string convertUI32ToHexString( unsigned int val );
/**
* Standard means for formatting a small hex string from a
* 32-bit unsigned value. The "0x" will NOT be included.
* Will produce upper-case letters. Will NOT pad with zeros
* at the beginning.
*
* @param the value to format
* @return the formatted value, like "DEADBEEF"
*/
static std::string convertUI32ToMinimalHexString( unsigned int val );
/**
* Assemble the fields of ENCRYPTED_BODY_HEADER and encrypt it for
* sending to the remote side.
* @param result is the out parameter having the resulting string.
* @param encKeyName is the name of the key in keydb whose value will be
* used as the encryption key
* @param bodyEncVersion is the version of the encryption scheme used to
* encrypt the body (not the encryption scheme of this header itself).
* @param expireTime is the time (in usecs) after which the request
* should not be processed by the receiver of this header.
*/
static FwCode::ResponseCode makeEncryptedBodyHdr(std::string & result,
const char *encKeyName, uint32_t bodyEncVersion, uint64_t expireTime);
/**
* Parse the incoming ENCRYPTED_BODY_HEADER, decrypting it, and
* separating the fields in it.
* @param inval is the incoming encrypted string.
* @param encKeyName is the name of the key in keydb whose value will be
* used as the decryption key
* @param bodyEncVersion is the version of the encryption scheme to be
* used to * decrypt the body (not for the decryption of this header
* itself).
* @param expireTime is the time (in usecs) after which the response
* should not be processed by the receiver of this header.
*/
static FwCode::ResponseCode parseEncryptedBodyHdr(const std::string & inval,
const char *encKeyName, uint32_t & bodyEncVersion, uint64_t & expireTime);
/**
* Get the hash for an un-normalized record name.
*
* @param unnormalizedRecordName a raw record name from user input
* @param (output) hashResult the hex string of the hash value.
* @return FwCode::FwOk on success, else an error relating to normalization
*/
static FwCode::ResponseCode normalizeAndHashRecordName
( const std::string& unnormalizedRecordName,
std::string & hashResult /* out */ );
/**
* Get the hash for a normalized record name.
*
* @param recordName the record name. MUST be previously normalized.
* @return hashResult the uint32_t of the hash value.
*/
static uint32_t hashRecordName(const std::string& recordName);
/**
* Get the hash for a normalized record name.
*
* @param recordName the record name. MUST be previously normalized.
* @param (output) hashResult the hex string of the hash value.
*/
static void hashRecordName( const std::string& recordName,
std::string & hashResult /* out */ );
/**
* Get the hash for a normalized record name in string and int form
*
* @param recordName the record name. MUST be previously normalized.
* @param (output) hashResult the hex string of the hash value.
* @param (output) hexNum numerical value of hash
*/
static void hashRecordName( const std::string& recordName,
std::string & hashResult /* out */,
uint32_t& hexNum);
/**
* Method to hash a string using crc32.
*
* @param buf data to hash
* @param len length of buf
* @return hash value
*/
static uint32_t crcHash(const char * buf, uint32_t len);
/**
* util function to convert any type to a string
*/
template<typename T> static inline std::string toString(T item);
/**
* convert string to any type of value
* @param strValue string value to parse
* @param value(out) value to read from strValue
* @return FwCode::FwOk on success
* FwCode::FwError on failure (error is *not* logged)
*/
template<typename T> static inline
FwCode::ResponseCode fromString(const std::string& strValue,
T& value);
/**
* convert a hexadecimal number to string representation
* of fixed width ( 2 * sizeof(T) )
* @param value number to convert to string
* @return string representation of value
*/
template<typename T> static inline
std::string numberToHexString(T value);
/**
* convert a hexadecimal number to minimal string representation
* @param value number to convert to string
* @return string representation of value
*/
template<typename T> static inline
std::string numberToMinimalHexString(T value);
/**
* convert a hexadecimal string to a number
* @param strvalue input string to read from
* @param value(out) output number
* @return FwCode::FwOk on successful conversion
* FwCode::FwError on failure to convert strvalue
* to number
*/
template<typename T> static inline
FwCode::ResponseCode hexStringToNumber(const std::string& strvalue,
T& value);
static const std::string EMPTY_STRING;
};
template<typename T>
std::string StringUtils::
toString(T item)
{
std::ostringstream buf;
buf << item;
return buf.str();
}
template<typename T>
FwCode::ResponseCode StringUtils::
fromString(const std::string& strValue,
T& value)
{
std::istringstream buf(strValue);
buf >> value;
if(buf.fail()||
(strValue.length() != buf.tellg() ))
{
return FwCode::FwError;
}
return FwCode::FwOk;
}
template<typename T>
std::string StringUtils::
numberToHexString(T value)
{
std::ostringstream buf;
buf << "0x" << std::hex
<< std::setw(sizeof(T) * 2) << std::setfill('0')
<< std::uppercase << value;
return buf.str();
}
template<typename T>
std::string StringUtils::
numberToMinimalHexString(T value)
{
std::ostringstream buf;
buf << std::hex << std::uppercase << value;
return buf.str();
}
template<typename T>
FwCode::ResponseCode StringUtils::
hexStringToNumber(const std::string& strvalue,
T& value)
{
std::istringstream buf(strvalue);
buf >> std::hex >> value;
if(buf.fail() ||
(strvalue.length() != buf.tellg() ))
{
return FwCode::FwError;
}
return FwCode::FwOk;
}
/*
* For customized vim control
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
* vim600: sw=4:ts=4:et
* vim<600: sw=4:ts=4:et
*/
#endif