//===-- StringExtractor.cpp -------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Utility/StringExtractor.h"
// C Includes
#include <stdlib.h>
// C++ Includes
// Other libraries and framework includes
// Project includes
static inline int
xdigit_to_sint (char ch)
{
if (ch >= 'a' && ch <= 'f')
return 10 + ch - 'a';
if (ch >= 'A' && ch <= 'F')
return 10 + ch - 'A';
if (ch >= '0' && ch <= '9')
return ch - '0';
return -1;
}
//----------------------------------------------------------------------
// StringExtractor constructor
//----------------------------------------------------------------------
StringExtractor::StringExtractor() :
m_packet(),
m_index (0)
{
}
StringExtractor::StringExtractor(const char *packet_cstr) :
m_packet(),
m_index (0)
{
if (packet_cstr)
m_packet.assign (packet_cstr);
}
//----------------------------------------------------------------------
// StringExtractor copy constructor
//----------------------------------------------------------------------
StringExtractor::StringExtractor(const StringExtractor& rhs) :
m_packet (rhs.m_packet),
m_index (rhs.m_index)
{
}
//----------------------------------------------------------------------
// StringExtractor assignment operator
//----------------------------------------------------------------------
const StringExtractor&
StringExtractor::operator=(const StringExtractor& rhs)
{
if (this != &rhs)
{
m_packet = rhs.m_packet;
m_index = rhs.m_index;
}
return *this;
}
//----------------------------------------------------------------------
// Destructor
//----------------------------------------------------------------------
StringExtractor::~StringExtractor()
{
}
char
StringExtractor::GetChar (char fail_value)
{
if (m_index < m_packet.size())
{
char ch = m_packet[m_index];
++m_index;
return ch;
}
m_index = UINT64_MAX;
return fail_value;
}
//----------------------------------------------------------------------
// If a pair of valid hex digits exist at the head of the
// StringExtractor they are decoded into an unsigned byte and returned
// by this function
//
// If there is not a pair of valid hex digits at the head of the
// StringExtractor, it is left unchanged and -1 is returned
//----------------------------------------------------------------------
int
StringExtractor::DecodeHexU8()
{
if (GetBytesLeft() < 2)
{
return -1;
}
const int hi_nibble = xdigit_to_sint(m_packet[m_index]);
const int lo_nibble = xdigit_to_sint(m_packet[m_index+1]);
if (hi_nibble == -1 || lo_nibble == -1)
{
return -1;
}
m_index += 2;
return (uint8_t)((hi_nibble << 4) + lo_nibble);
}
//----------------------------------------------------------------------
// Extract an unsigned character from two hex ASCII chars in the packet
// string
//----------------------------------------------------------------------
uint8_t
StringExtractor::GetHexU8 (uint8_t fail_value, bool set_eof_on_fail)
{
int byte = DecodeHexU8();
if (byte == -1)
{
if (set_eof_on_fail || m_index >= m_packet.size())
m_index = UINT64_MAX;
return fail_value;
}
return (uint8_t)byte;
}
uint32_t
StringExtractor::GetU32 (uint32_t fail_value, int base)
{
if (m_index < m_packet.size())
{
char *end = nullptr;
const char *start = m_packet.c_str();
const char *cstr = start + m_index;
uint32_t result = static_cast<uint32_t>(::strtoul (cstr, &end, base));
if (end && end != cstr)
{
m_index = end - start;
return result;
}
}
return fail_value;
}
int32_t
StringExtractor::GetS32 (int32_t fail_value, int base)
{
if (m_index < m_packet.size())
{
char *end = nullptr;
const char *start = m_packet.c_str();
const char *cstr = start + m_index;
int32_t result = static_cast<int32_t>(::strtol (cstr, &end, base));
if (end && end != cstr)
{
m_index = end - start;
return result;
}
}
return fail_value;
}
uint64_t
StringExtractor::GetU64 (uint64_t fail_value, int base)
{
if (m_index < m_packet.size())
{
char *end = nullptr;
const char *start = m_packet.c_str();
const char *cstr = start + m_index;
uint64_t result = ::strtoull (cstr, &end, base);
if (end && end != cstr)
{
m_index = end - start;
return result;
}
}
return fail_value;
}
int64_t
StringExtractor::GetS64 (int64_t fail_value, int base)
{
if (m_index < m_packet.size())
{
char *end = nullptr;
const char *start = m_packet.c_str();
const char *cstr = start + m_index;
int64_t result = ::strtoll (cstr, &end, base);
if (end && end != cstr)
{
m_index = end - start;
return result;
}
}
return fail_value;
}
uint32_t
StringExtractor::GetHexMaxU32 (bool little_endian, uint32_t fail_value)
{
uint32_t result = 0;
uint32_t nibble_count = 0;
if (little_endian)
{
uint32_t shift_amount = 0;
while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
// Make sure we don't exceed the size of a uint32_t...
if (nibble_count >= (sizeof(uint32_t) * 2))
{
m_index = UINT64_MAX;
return fail_value;
}
uint8_t nibble_lo;
uint8_t nibble_hi = xdigit_to_sint (m_packet[m_index]);
++m_index;
if (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
nibble_lo = xdigit_to_sint (m_packet[m_index]);
++m_index;
result |= ((uint32_t)nibble_hi << (shift_amount + 4));
result |= ((uint32_t)nibble_lo << shift_amount);
nibble_count += 2;
shift_amount += 8;
}
else
{
result |= ((uint32_t)nibble_hi << shift_amount);
nibble_count += 1;
shift_amount += 4;
}
}
}
else
{
while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
// Make sure we don't exceed the size of a uint32_t...
if (nibble_count >= (sizeof(uint32_t) * 2))
{
m_index = UINT64_MAX;
return fail_value;
}
uint8_t nibble = xdigit_to_sint (m_packet[m_index]);
// Big Endian
result <<= 4;
result |= nibble;
++m_index;
++nibble_count;
}
}
return result;
}
uint64_t
StringExtractor::GetHexMaxU64 (bool little_endian, uint64_t fail_value)
{
uint64_t result = 0;
uint32_t nibble_count = 0;
if (little_endian)
{
uint32_t shift_amount = 0;
while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
// Make sure we don't exceed the size of a uint64_t...
if (nibble_count >= (sizeof(uint64_t) * 2))
{
m_index = UINT64_MAX;
return fail_value;
}
uint8_t nibble_lo;
uint8_t nibble_hi = xdigit_to_sint (m_packet[m_index]);
++m_index;
if (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
nibble_lo = xdigit_to_sint (m_packet[m_index]);
++m_index;
result |= ((uint64_t)nibble_hi << (shift_amount + 4));
result |= ((uint64_t)nibble_lo << shift_amount);
nibble_count += 2;
shift_amount += 8;
}
else
{
result |= ((uint64_t)nibble_hi << shift_amount);
nibble_count += 1;
shift_amount += 4;
}
}
}
else
{
while (m_index < m_packet.size() && ::isxdigit (m_packet[m_index]))
{
// Make sure we don't exceed the size of a uint64_t...
if (nibble_count >= (sizeof(uint64_t) * 2))
{
m_index = UINT64_MAX;
return fail_value;
}
uint8_t nibble = xdigit_to_sint (m_packet[m_index]);
// Big Endian
result <<= 4;
result |= nibble;
++m_index;
++nibble_count;
}
}
return result;
}
size_t
StringExtractor::GetHexBytes (void *dst_void, size_t dst_len, uint8_t fail_fill_value)
{
uint8_t *dst = (uint8_t*)dst_void;
size_t bytes_extracted = 0;
while (bytes_extracted < dst_len && GetBytesLeft ())
{
dst[bytes_extracted] = GetHexU8 (fail_fill_value);
if (IsGood())
++bytes_extracted;
else
break;
}
for (size_t i = bytes_extracted; i < dst_len; ++i)
dst[i] = fail_fill_value;
return bytes_extracted;
}
//----------------------------------------------------------------------
// Decodes all valid hex encoded bytes at the head of the
// StringExtractor, limited by dst_len.
//
// Returns the number of bytes successfully decoded
//----------------------------------------------------------------------
size_t
StringExtractor::GetHexBytesAvail (void *dst_void, size_t dst_len)
{
uint8_t *dst = (uint8_t*)dst_void;
size_t bytes_extracted = 0;
while (bytes_extracted < dst_len)
{
int decode = DecodeHexU8();
if (decode == -1)
{
break;
}
dst[bytes_extracted++] = (uint8_t)decode;
}
return bytes_extracted;
}
// Consume ASCII hex nibble character pairs until we have decoded byte_size
// bytes of data.
uint64_t
StringExtractor::GetHexWithFixedSize (uint32_t byte_size, bool little_endian, uint64_t fail_value)
{
if (byte_size <= 8 && GetBytesLeft() >= byte_size * 2)
{
uint64_t result = 0;
uint32_t i;
if (little_endian)
{
// Little Endian
uint32_t shift_amount;
for (i = 0, shift_amount = 0;
i < byte_size && IsGood();
++i, shift_amount += 8)
{
result |= ((uint64_t)GetHexU8() << shift_amount);
}
}
else
{
// Big Endian
for (i = 0; i < byte_size && IsGood(); ++i)
{
result <<= 8;
result |= GetHexU8();
}
}
}
m_index = UINT64_MAX;
return fail_value;
}
size_t
StringExtractor::GetHexByteString (std::string &str)
{
str.clear();
char ch;
while ((ch = GetHexU8()) != '\0')
str.append(1, ch);
return str.size();
}
size_t
StringExtractor::GetHexByteStringFixedLength (std::string &str, uint32_t nibble_length)
{
str.clear();
uint32_t nibble_count = 0;
for (const char *pch = Peek(); (nibble_count < nibble_length) && (pch != nullptr); str.append(1, GetHexU8(0, false)), pch = Peek (), nibble_count += 2)
{}
return str.size();
}
size_t
StringExtractor::GetHexByteStringTerminatedBy (std::string &str,
char terminator)
{
str.clear();
char ch;
while ((ch = GetHexU8(0,false)) != '\0')
str.append(1, ch);
if (Peek() && *Peek() == terminator)
return str.size();
str.clear();
return str.size();
}
bool
StringExtractor::GetNameColonValue (std::string &name, std::string &value)
{
// Read something in the form of NNNN:VVVV; where NNNN is any character
// that is not a colon, followed by a ':' character, then a value (one or
// more ';' chars), followed by a ';'
if (m_index < m_packet.size())
{
const size_t colon_idx = m_packet.find (':', m_index);
if (colon_idx != std::string::npos)
{
const size_t semicolon_idx = m_packet.find (';', colon_idx);
if (semicolon_idx != std::string::npos)
{
name.assign (m_packet, m_index, colon_idx - m_index);
value.assign (m_packet, colon_idx + 1, semicolon_idx - (colon_idx + 1));
m_index = semicolon_idx + 1;
return true;
}
}
}
m_index = UINT64_MAX;
return false;
}
void
StringExtractor::SkipSpaces ()
{
const size_t n = m_packet.size();
while (m_index < n && isspace(m_packet[m_index]))
++m_index;
}
