pmd-red/tools/preproc/string_parser.cpp

358 lines
9.0 KiB
C++

// Copyright(c) 2016 YamaArashi
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#include <cstdio>
#include <cstdarg>
#include <stdexcept>
#include "preproc.h"
#include "string_parser.h"
#include "char_util.h"
#include "utf8.h"
// Reads a charmap char or escape sequence.
std::string StringParser::ReadCharOrEscape()
{
std::string sequence;
bool isEscape = (m_buffer[m_pos] == '\\');
if (isEscape)
{
m_pos++;
if (m_buffer[m_pos] == '"')
{
sequence = g_charmap->Char('"');
if (sequence.length() == 0)
RaiseError("no mapping exists for double quote");
m_pos++;
return sequence;
}
else if (m_buffer[m_pos] == '\\')
{
sequence = g_charmap->Char('\\');
if (sequence.length() == 0)
RaiseError("no mapping exists for backslash");
m_pos++;
return sequence;
}
}
unsigned char c = m_buffer[m_pos];
if (c == 0)
{
if (m_pos >= m_size)
RaiseError("unexpected EOF in UTF-8 string");
else
RaiseError("unexpected null character in UTF-8 string");
}
if (IsAscii(c) && !IsAsciiPrintable(c))
RaiseError("unexpected character U+%X in UTF-8 string", c);
UnicodeChar unicodeChar = DecodeUtf8(&m_buffer[m_pos]);
m_pos += unicodeChar.encodingLength;
std::int32_t code = unicodeChar.code;
if (code == -1)
RaiseError("invalid encoding in UTF-8 string");
if (isEscape && code >= 128)
RaiseError("escapes using non-ASCII characters are invalid");
sequence = isEscape ? g_charmap->Escape(code) : g_charmap->Char(code);
if (sequence.length() == 0)
{
if (isEscape)
RaiseError("unknown escape '\\%c'", code);
else
RaiseError("unknown character U+%X", code);
}
return sequence;
}
// Reads a charmap constant, i.e. "{FOO}".
std::string StringParser::ReadBracketedConstants()
{
std::string totalSequence;
m_pos++; // Assume we're on the left curly bracket.
while (m_buffer[m_pos] != '}')
{
SkipWhitespace();
if (IsIdentifierStartingChar(m_buffer[m_pos]))
{
long startPos = m_pos;
m_pos++;
while (IsIdentifierChar(m_buffer[m_pos]))
m_pos++;
std::string sequence = g_charmap->Constant(std::string(&m_buffer[startPos], m_pos - startPos));
if (sequence.length() == 0)
{
m_buffer[m_pos] = 0;
RaiseError("unknown constant '%s'", &m_buffer[startPos]);
}
totalSequence += sequence;
}
else if (IsAsciiDigit(m_buffer[m_pos]))
{
Integer integer = ReadInteger();
switch (integer.size)
{
case 1:
totalSequence += (unsigned char)integer.value;
break;
case 2:
totalSequence += (unsigned char)integer.value;
totalSequence += (unsigned char)(integer.value >> 8);
break;
case 4:
totalSequence += (unsigned char)integer.value;
totalSequence += (unsigned char)(integer.value >> 8);
totalSequence += (unsigned char)(integer.value >> 16);
totalSequence += (unsigned char)(integer.value >> 24);
break;
}
}
else if (m_buffer[m_pos] == 0)
{
if (m_pos >= m_size)
RaiseError("unexpected EOF after left curly bracket");
else
RaiseError("unexpected null character within curly brackets");
}
else
{
if (IsAsciiPrintable(m_buffer[m_pos]))
RaiseError("unexpected character '%c' within curly brackets", m_buffer[m_pos]);
else
RaiseError("unexpected character '\\x%02X' within curly brackets", m_buffer[m_pos]);
}
}
m_pos++; // Go past the right curly bracket.
return totalSequence;
}
// Reads a charmap string.
int StringParser::ParseString(long srcPos, unsigned char* dest, int& destLength)
{
m_pos = srcPos;
if (m_buffer[m_pos] != '"')
RaiseError("expected UTF-8 string literal");
long start = m_pos;
m_pos++;
destLength = 0;
while (m_buffer[m_pos] != '"')
{
std::string sequence = (m_buffer[m_pos] == '{') ? ReadBracketedConstants() : ReadCharOrEscape();
for (const char& c : sequence)
{
if (destLength == kMaxStringLength)
RaiseError("mapped string longer than %d bytes", kMaxStringLength);
dest[destLength++] = c;
}
}
m_pos++; // Go past the right quote.
return m_pos - start;
}
void StringParser::RaiseError(const char* format, ...)
{
const int bufferSize = 1024;
char buffer[bufferSize];
std::va_list args;
va_start(args, format);
std::vsnprintf(buffer, bufferSize, format, args);
va_end(args);
throw std::runtime_error(buffer);
}
// Converts digit character to numerical value.
static int ConvertDigit(char c, int radix)
{
int digit;
if (c >= '0' && c <= '9')
digit = c - '0';
else if (c >= 'A' && c <= 'F')
digit = 10 + c - 'A';
else if (c >= 'a' && c <= 'f')
digit = 10 + c - 'a';
else
return -1;
return (digit < radix) ? digit : -1;
}
void StringParser::SkipRestOfInteger(int radix)
{
while (ConvertDigit(m_buffer[m_pos], radix) != -1)
m_pos++;
}
StringParser::Integer StringParser::ReadDecimal()
{
const int radix = 10;
std::uint64_t n = 0;
int digit;
std::uint64_t max = UINT32_MAX;
long startPos = m_pos;
while ((digit = ConvertDigit(m_buffer[m_pos], radix)) != -1)
{
n = n * radix + digit;
if (n >= max)
{
SkipRestOfInteger(radix);
std::string intLiteral(m_buffer + startPos, m_pos - startPos);
RaiseError("integer literal \"%s\" is too large", intLiteral.c_str());
}
m_pos++;
}
int size;
if (m_buffer[m_pos] == 'H')
{
if (n >= 0x10000)
{
RaiseError("%lu is too large to be a halfword", (unsigned long)n);
}
size = 2;
m_pos++;
}
else if (m_buffer[m_pos] == 'W')
{
size = 4;
m_pos++;
}
else
{
if (n >= 0x10000)
size = 4;
else if (n >= 0x100)
size = 2;
else
size = 1;
}
return{ static_cast<std::uint32_t>(n), size };
}
StringParser::Integer StringParser::ReadHex()
{
const int radix = 16;
std::uint64_t n = 0;
int digit;
std::uint64_t max = UINT32_MAX;
long startPos = m_pos;
while ((digit = ConvertDigit(m_buffer[m_pos], radix)) != -1)
{
n = n * radix + digit;
if (n >= max)
{
SkipRestOfInteger(radix);
std::string intLiteral(m_buffer + startPos, m_pos - startPos);
RaiseError("integer literal \"%s\" is too large", intLiteral.c_str());
}
m_pos++;
}
int length = m_pos - startPos;
int size = 0;
switch (length)
{
case 2:
size = 1;
break;
case 4:
size = 2;
break;
case 8:
size = 4;
break;
default:
{
std::string intLiteral(m_buffer + startPos, m_pos - startPos);
RaiseError("hex integer literal \"0x%s\" doesn't have length of 2, 4, or 8 digits", intLiteral.c_str());
}
}
return{ static_cast<std::uint32_t>(n), size };
}
StringParser::Integer StringParser::ReadInteger()
{
if (!IsAsciiDigit(m_buffer[m_pos]))
RaiseError("expected integer");
if (m_buffer[m_pos] == '0' && m_buffer[m_pos + 1] == 'x')
{
m_pos += 2;
return ReadHex();
}
return ReadDecimal();
}
// Skips tabs and spaces.
void StringParser::SkipWhitespace()
{
while (m_buffer[m_pos] == '\t' || m_buffer[m_pos] == ' ')
m_pos++;
}