Revision 142b54530dfe3f8f40b96da52ed8a081348668dd authored by a1ex on 27 January 2015, 20:48:44 UTC, committed by a1ex on 27 January 2015, 20:48:44 UTC
1 parent 2e7479d
lex.c
#include "interpreter.h"
#ifdef NO_CTYPE
#define isalpha(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
#define isdigit(c) ((c) >= '0' && (c) <= '9')
#define isalnum(c) (isalpha(c) || isdigit(c))
#define isspace(c) ((c) == ' ' || (c) == '\t' || (c) == '\r' || (c) == '\n')
#endif
#define isCidstart(c) (isalpha(c) || (c)=='_' || (c)=='#')
#define isCident(c) (isalnum(c) || (c)=='_')
#define IS_HEX_ALPHA_DIGIT(c) (((c) >= 'a' && (c) <= 'f') || ((c) >= 'A' && (c) <= 'F'))
#define IS_BASE_DIGIT(c,b) (((c) >= '0' && (c) < '0' + (((b)<10)?(b):10)) || (((b) > 10) ? IS_HEX_ALPHA_DIGIT(c) : FALSE))
#define GET_BASE_DIGIT(c) (((c) <= '9') ? ((c) - '0') : (((c) <= 'F') ? ((c) - 'A' + 10) : ((c) - 'a' + 10)))
#define NEXTIS(c,x,y) { if (NextChar == (c)) { LEXER_INC(Lexer); GotToken = (x); } else GotToken = (y); }
#define NEXTIS3(c,x,d,y,z) { if (NextChar == (c)) { LEXER_INC(Lexer); GotToken = (x); } else NEXTIS(d,y,z) }
#define NEXTIS4(c,x,d,y,e,z,a) { if (NextChar == (c)) { LEXER_INC(Lexer); GotToken = (x); } else NEXTIS3(d,y,e,z,a) }
#define NEXTIS3PLUS(c,x,d,y,e,z,a) { if (NextChar == (c)) { LEXER_INC(Lexer); GotToken = (x); } else if (NextChar == (d)) { if (Lexer->Pos[1] == (e)) { LEXER_INCN(Lexer, 2); GotToken = (z); } else { LEXER_INC(Lexer); GotToken = (y); } } else GotToken = (a); }
#define NEXTISEXACTLY3(c,d,y,z) { if (NextChar == (c) && Lexer->Pos[1] == (d)) { LEXER_INCN(Lexer, 2); GotToken = (y); } else GotToken = (z); }
#define LEXER_INC(l) ( (l)->Pos++, (l)->CharacterPos++ )
#define LEXER_INCN(l, n) ( (l)->Pos+=(n), (l)->CharacterPos+=(n) )
#define TOKEN_DATA_OFFSET 2
#define MAX_CHAR_VALUE 255 /* maximum value which can be represented by a "char" data type */
static union AnyValue LexAnyValue;
static struct Value LexValue = { TypeVoid, &LexAnyValue, FALSE, FALSE };
struct ReservedWord
{
const char *Word;
enum LexToken Token;
const char *SharedWord; /* word stored in shared string space */
};
static struct ReservedWord ReservedWords[] =
{
{ "#define", TokenHashDefine, NULL },
{ "#else", TokenHashElse, NULL },
{ "#endif", TokenHashEndif, NULL },
{ "#if", TokenHashIf, NULL },
{ "#ifdef", TokenHashIfdef, NULL },
{ "#ifndef", TokenHashIfndef, NULL },
{ "#include", TokenHashInclude, NULL },
{ "auto", TokenAutoType, NULL },
{ "break", TokenBreak, NULL },
{ "case", TokenCase, NULL },
{ "char", TokenCharType, NULL },
{ "continue", TokenContinue, NULL },
{ "default", TokenDefault, NULL },
{ "delete", TokenDelete, NULL },
{ "do", TokenDo, NULL },
#ifndef NO_FP
{ "double", TokenDoubleType, NULL },
#endif
{ "else", TokenElse, NULL },
{ "enum", TokenEnumType, NULL },
{ "extern", TokenExternType, NULL },
#ifndef NO_FP
{ "float", TokenFloatType, NULL },
#endif
{ "for", TokenFor, NULL },
{ "goto", TokenGoto, NULL },
{ "if", TokenIf, NULL },
{ "int", TokenIntType, NULL },
{ "long", TokenLongType, NULL },
{ "new", TokenNew, NULL },
{ "register", TokenRegisterType, NULL },
{ "return", TokenReturn, NULL },
{ "short", TokenShortType, NULL },
{ "signed", TokenSignedType, NULL },
{ "sizeof", TokenSizeof, NULL },
{ "static", TokenStaticType, NULL },
{ "struct", TokenStructType, NULL },
{ "switch", TokenSwitch, NULL },
{ "typedef", TokenTypedef, NULL },
{ "union", TokenUnionType, NULL },
{ "unsigned", TokenUnsignedType, NULL },
{ "void", TokenVoidType, NULL },
{ "while", TokenWhile, NULL }
};
/* linked list of tokens used in interactive mode */
struct TokenLine
{
struct TokenLine *Next;
unsigned char *Tokens;
int NumBytes;
};
static struct TokenLine *InteractiveHead = NULL;
static struct TokenLine *InteractiveTail = NULL;
static struct TokenLine *InteractiveCurrentLine = NULL;
static int LexUseStatementPrompt = FALSE;
/* initialise the lexer */
void LexInit()
{
int Count;
for (Count = 0; Count < (int)(sizeof(ReservedWords) / sizeof(struct ReservedWord)); Count++)
ReservedWords[Count].SharedWord = TableStrRegister(ReservedWords[Count].Word);
}
/* deallocate */
void LexCleanup()
{
LexInteractiveClear(NULL);
}
/* check if a word is a reserved word - used while scanning */
enum LexToken LexCheckReservedWord(const char *Word)
{
int Count;
for (Count = 0; Count < (int)(sizeof(ReservedWords) / sizeof(struct ReservedWord)); Count++)
{
if (Word == ReservedWords[Count].SharedWord)
return ReservedWords[Count].Token;
}
return TokenNone;
}
/* get a numeric literal - used while scanning */
enum LexToken LexGetNumber(struct LexState *Lexer, struct Value *Value)
{
int Result = 0;
int Base = 10;
enum LexToken ResultToken;
#ifndef NO_FP
double FPResult;
double FPDiv;
#endif
if (*Lexer->Pos == '0')
{
/* a binary, octal or hex literal */
LEXER_INC(Lexer);
if (Lexer->Pos != Lexer->End)
{
if (*Lexer->Pos == 'x' || *Lexer->Pos == 'X')
{ Base = 16; LEXER_INC(Lexer); }
else if (*Lexer->Pos == 'b' || *Lexer->Pos == 'B')
{ Base = 2; LEXER_INC(Lexer); }
else if (*Lexer->Pos != '.')
Base = 8;
}
}
/* get the value */
for (; Lexer->Pos != Lexer->End && IS_BASE_DIGIT(*Lexer->Pos, Base); LEXER_INC(Lexer))
Result = Result * Base + GET_BASE_DIGIT(*Lexer->Pos);
if (Result >= 0 && Result <= MAX_CHAR_VALUE)
{
Value->Typ = &CharType;
Value->Val->Character = Result;
ResultToken = TokenCharacterConstant;
}
else
{
Value->Typ = &IntType;
Value->Val->Integer = Result;
ResultToken = TokenIntegerConstant;
}
if (Lexer->Pos == Lexer->End)
return ResultToken;
if (*Lexer->Pos == 'l' || *Lexer->Pos == 'L')
{
LEXER_INC(Lexer);
return ResultToken;
}
#ifndef NO_FP
if (Lexer->Pos == Lexer->End || *Lexer->Pos != '.')
return ResultToken;
Value->Typ = &FPType;
LEXER_INC(Lexer);
for (FPDiv = 1.0/Base, FPResult = (double)Result; Lexer->Pos != Lexer->End && IS_BASE_DIGIT(*Lexer->Pos, Base); LEXER_INC(Lexer), FPDiv /= (double)Base)
FPResult += GET_BASE_DIGIT(*Lexer->Pos) * FPDiv;
if (Lexer->Pos != Lexer->End && (*Lexer->Pos == 'e' || *Lexer->Pos == 'E'))
{
double ExponentMultiplier = 1.0;
LEXER_INC(Lexer);
if (Lexer->Pos != Lexer->End && *Lexer->Pos == '-')
{
ExponentMultiplier = -1.0;
LEXER_INC(Lexer);
}
for (Result = 0; Lexer->Pos != Lexer->End && IS_BASE_DIGIT(*Lexer->Pos, Base); LEXER_INC(Lexer))
Result = Result * (double)Base + GET_BASE_DIGIT(*Lexer->Pos);
FPResult *= pow((double)Base, (double)Result * ExponentMultiplier);
}
Value->Val->FP = FPResult;
return TokenFPConstant;
#else
return ResultToken;
#endif
}
/* get a reserved word or identifier - used while scanning */
enum LexToken LexGetWord(struct LexState *Lexer, struct Value *Value)
{
const char *StartPos = Lexer->Pos;
enum LexToken Token;
do {
LEXER_INC(Lexer);
} while (Lexer->Pos != Lexer->End && isCident((int)*Lexer->Pos));
Value->Typ = NULL;
Value->Val->Identifier = TableStrRegister2(StartPos, Lexer->Pos - StartPos);
Token = LexCheckReservedWord(Value->Val->Identifier);
switch (Token)
{
case TokenHashInclude: Lexer->Mode = LexModeHashInclude; break;
case TokenHashDefine: Lexer->Mode = LexModeHashDefine; break;
default: break;
}
if (Token != TokenNone)
return Token;
if (Lexer->Mode == LexModeHashDefineSpace)
Lexer->Mode = LexModeHashDefineSpaceIdent;
return TokenIdentifier;
}
/* unescape a character from an octal character constant */
unsigned char LexUnEscapeCharacterConstant(const char **From, const char *End, unsigned char FirstChar, int Base)
{
unsigned char Total = GET_BASE_DIGIT(FirstChar);
int CCount;
for (CCount = 0; IS_BASE_DIGIT(**From, Base) && CCount < 2; CCount++, (*From)++)
Total = Total * Base + GET_BASE_DIGIT(**From);
return Total;
}
/* unescape a character from a string or character constant */
unsigned char LexUnEscapeCharacter(const char **From, const char *End)
{
unsigned char ThisChar;
while ( *From != End && **From == '\\' &&
&(*From)[1] != End && (*From)[1] == '\n' )
(*From) += 2; /* skip escaped end of lines with LF line termination */
while ( *From != End && **From == '\\' &&
&(*From)[1] != End && &(*From)[2] != End && (*From)[1] == '\r' && (*From)[2] == '\n')
(*From) += 3; /* skip escaped end of lines with CR/LF line termination */
if (*From == End)
return '\\';
if (**From == '\\')
{
/* it's escaped */
(*From)++;
if (*From == End)
return '\\';
ThisChar = *(*From)++;
switch (ThisChar)
{
case '\\': return '\\';
case '\'': return '\'';
case '"': return '"';
case 'a': return '\a';
case 'b': return '\b';
case 'f': return '\f';
case 'n': return '\n';
case 'r': return '\r';
case 't': return '\t';
case 'v': return '\v';
case '0': case '1': case '2': case '3': return LexUnEscapeCharacterConstant(From, End, ThisChar, 8);
case 'x': return LexUnEscapeCharacterConstant(From, End, '0', 16);
default: return ThisChar;
}
}
else
return *(*From)++;
}
/* get a string constant - used while scanning */
enum LexToken LexGetStringConstant(struct LexState *Lexer, struct Value *Value, char EndChar)
{
int Escape = FALSE;
const char *StartPos = Lexer->Pos;
const char *EndPos;
char *EscBuf;
char *EscBufPos;
char *RegString;
struct Value *ArrayValue;
while (Lexer->Pos != Lexer->End && (*Lexer->Pos != EndChar || Escape))
{
/* find the end */
if (Escape)
{
if (*Lexer->Pos == '\r' && Lexer->Pos+1 != Lexer->End)
Lexer->Pos++;
if (*Lexer->Pos == '\n' && Lexer->Pos+1 != Lexer->End)
{
Lexer->Line++;
Lexer->Pos++;
Lexer->CharacterPos = 0;
Lexer->EmitExtraNewlines++;
}
Escape = FALSE;
}
else if (*Lexer->Pos == '\\')
Escape = TRUE;
LEXER_INC(Lexer);
}
EndPos = Lexer->Pos;
EscBuf = HeapAllocStack(EndPos - StartPos);
if (EscBuf == NULL)
LexFail(Lexer, "out of memory");
for (EscBufPos = EscBuf, Lexer->Pos = StartPos; Lexer->Pos != EndPos;)
*EscBufPos++ = LexUnEscapeCharacter(&Lexer->Pos, EndPos);
/* try to find an existing copy of this string literal */
RegString = TableStrRegister2(EscBuf, EscBufPos - EscBuf);
HeapPopStack(EscBuf, EndPos - StartPos);
ArrayValue = VariableStringLiteralGet(RegString);
if (ArrayValue == NULL)
{
/* create and store this string literal */
ArrayValue = VariableAllocValueAndData(NULL, 0, FALSE, NULL, TRUE);
ArrayValue->Typ = CharArrayType;
ArrayValue->Val = (union AnyValue *)RegString;
VariableStringLiteralDefine(RegString, ArrayValue);
}
/* create the the pointer for this char* */
Value->Typ = CharPtrType;
Value->Val->Pointer = RegString;
if (*Lexer->Pos == EndChar)
LEXER_INC(Lexer);
return TokenStringConstant;
}
/* get a character constant - used while scanning */
enum LexToken LexGetCharacterConstant(struct LexState *Lexer, struct Value *Value)
{
Value->Typ = &CharType;
Value->Val->Character = LexUnEscapeCharacter(&Lexer->Pos, Lexer->End);
if (Lexer->Pos != Lexer->End && *Lexer->Pos != '\'')
LexFail(Lexer, "expected \"'\"");
LEXER_INC(Lexer);
return TokenCharacterConstant;
}
/* skip a comment - used while scanning */
void LexSkipComment(struct LexState *Lexer, char NextChar, enum LexToken *ReturnToken)
{
if (NextChar == '*')
{
/* conventional C comment */
while (Lexer->Pos != Lexer->End && (*(Lexer->Pos-1) != '*' || *Lexer->Pos != '/'))
{
if (*Lexer->Pos == '\n')
Lexer->EmitExtraNewlines++;
LEXER_INC(Lexer);
}
if (Lexer->Pos != Lexer->End)
LEXER_INC(Lexer);
Lexer->Mode = LexModeNormal;
}
else
{
/* C++ style comment */
while (Lexer->Pos != Lexer->End && *Lexer->Pos != '\n')
LEXER_INC(Lexer);
}
}
/* get a single token from the source - used while scanning */
enum LexToken LexScanGetToken(struct LexState *Lexer, struct Value **Value)
{
char ThisChar;
char NextChar;
enum LexToken GotToken = TokenNone;
/* handle cases line multi-line comments or string constants which mess up the line count */
if (Lexer->EmitExtraNewlines > 0)
{
Lexer->EmitExtraNewlines--;
return TokenEndOfLine;
}
/* scan for a token */
do
{
*Value = &LexValue;
while (Lexer->Pos != Lexer->End && isspace((int)*Lexer->Pos))
{
if (*Lexer->Pos == '\n')
{
Lexer->Line++;
Lexer->Pos++;
Lexer->Mode = LexModeNormal;
Lexer->CharacterPos = 0;
return TokenEndOfLine;
}
else if (Lexer->Mode == LexModeHashDefine || Lexer->Mode == LexModeHashDefineSpace)
Lexer->Mode = LexModeHashDefineSpace;
else if (Lexer->Mode == LexModeHashDefineSpaceIdent)
Lexer->Mode = LexModeNormal;
LEXER_INC(Lexer);
}
if (Lexer->Pos == Lexer->End || *Lexer->Pos == '\0')
return TokenEOF;
ThisChar = *Lexer->Pos;
if (isCidstart((int)ThisChar))
return LexGetWord(Lexer, *Value);
if (isdigit((int)ThisChar))
return LexGetNumber(Lexer, *Value);
NextChar = (Lexer->Pos+1 != Lexer->End) ? *(Lexer->Pos+1) : 0;
LEXER_INC(Lexer);
switch (ThisChar)
{
case '"': GotToken = LexGetStringConstant(Lexer, *Value, '"'); break;
case '\'': GotToken = LexGetCharacterConstant(Lexer, *Value); break;
case '(': if (Lexer->Mode == LexModeHashDefineSpaceIdent) GotToken = TokenOpenMacroBracket; else GotToken = TokenOpenBracket; Lexer->Mode = LexModeNormal; break;
case ')': GotToken = TokenCloseBracket; break;
case '=': NEXTIS('=', TokenEqual, TokenAssign); break;
case '+': NEXTIS3('=', TokenAddAssign, '+', TokenIncrement, TokenPlus); break;
case '-': NEXTIS4('=', TokenSubtractAssign, '>', TokenArrow, '-', TokenDecrement, TokenMinus); break;
case '*': NEXTIS('=', TokenMultiplyAssign, TokenAsterisk); break;
case '/': if (NextChar == '/' || NextChar == '*') { LEXER_INC(Lexer); LexSkipComment(Lexer, NextChar, &GotToken); } else NEXTIS('=', TokenDivideAssign, TokenSlash); break;
case '%': NEXTIS('=', TokenModulusAssign, TokenModulus); break;
case '<': if (Lexer->Mode == LexModeHashInclude) GotToken = LexGetStringConstant(Lexer, *Value, '>'); else { NEXTIS3PLUS('=', TokenLessEqual, '<', TokenShiftLeft, '=', TokenShiftLeftAssign, TokenLessThan); } break;
case '>': NEXTIS3PLUS('=', TokenGreaterEqual, '>', TokenShiftRight, '=', TokenShiftRightAssign, TokenGreaterThan); break;
case ';': GotToken = TokenSemicolon; break;
case '&': NEXTIS3('=', TokenArithmeticAndAssign, '&', TokenLogicalAnd, TokenAmpersand); break;
case '|': NEXTIS3('=', TokenArithmeticOrAssign, '|', TokenLogicalOr, TokenArithmeticOr); break;
case '{': GotToken = TokenLeftBrace; break;
case '}': GotToken = TokenRightBrace; break;
case '[': GotToken = TokenLeftSquareBracket; break;
case ']': GotToken = TokenRightSquareBracket; break;
case '!': NEXTIS('=', TokenNotEqual, TokenUnaryNot); break;
case '^': NEXTIS('=', TokenArithmeticExorAssign, TokenArithmeticExor); break;
case '~': GotToken = TokenUnaryExor; break;
case ',': GotToken = TokenComma; break;
case '.': NEXTISEXACTLY3('.', '.', TokenEllipsis, TokenDot); break;
case '?': GotToken = TokenQuestionMark; break;
case ':': GotToken = TokenColon; break;
default: LexFail(Lexer, "illegal character '%c'", ThisChar); break;
}
} while (GotToken == TokenNone);
return GotToken;
}
/* what size value goes with each token */
int LexTokenSize(enum LexToken Token)
{
switch (Token)
{
case TokenIdentifier: case TokenStringConstant: return sizeof(char *);
case TokenIntegerConstant: return sizeof(int);
case TokenCharacterConstant: return sizeof(unsigned char);
case TokenFPConstant: return sizeof(double);
default: return 0;
}
}
/* produce tokens from the lexer and return a heap buffer with the result - used for scanning */
void *LexTokenise(struct LexState *Lexer, int *TokenLen)
{
enum LexToken Token;
void *HeapMem;
struct Value *GotValue;
int MemUsed = 0;
int ValueSize;
int ReserveSpace = (Lexer->End - Lexer->Pos) * 4 + 16;
void *TokenSpace = HeapAllocStack(ReserveSpace);
char *TokenPos = (char *)TokenSpace;
int LastCharacterPos = 0;
if (TokenSpace == NULL)
LexFail(Lexer, "out of memory");
do
{
/* store the token at the end of the stack area */
Token = LexScanGetToken(Lexer, &GotValue);
#ifdef DEBUG_LEXER
printf("Token: %02x\n", Token);
#endif
*(unsigned char *)TokenPos = Token;
TokenPos++;
MemUsed++;
*(unsigned char *)TokenPos = (unsigned char)LastCharacterPos;
TokenPos++;
MemUsed++;
ValueSize = LexTokenSize(Token);
if (ValueSize > 0)
{
/* store a value as well */
memcpy((void *)TokenPos, (void *)GotValue->Val, ValueSize);
TokenPos += ValueSize;
MemUsed += ValueSize;
}
LastCharacterPos = Lexer->CharacterPos;
} while (Token != TokenEOF);
HeapMem = HeapAllocMem(MemUsed);
if (HeapMem == NULL)
LexFail(Lexer, "out of memory");
assert(ReserveSpace >= MemUsed);
memcpy(HeapMem, TokenSpace, MemUsed);
HeapPopStack(TokenSpace, ReserveSpace);
#ifdef DEBUG_LEXER
{
int Count;
printf("Tokens: ");
for (Count = 0; Count < MemUsed; Count++)
printf("%02x ", *((unsigned char *)HeapMem+Count));
printf("\n");
}
#endif
if (TokenLen)
*TokenLen = MemUsed;
return HeapMem;
}
/* lexically analyse some source text */
void *LexAnalyse(const char *FileName, const char *Source, int SourceLen, int *TokenLen)
{
struct LexState Lexer;
Lexer.Pos = Source;
Lexer.End = Source + SourceLen;
Lexer.Line = 1;
Lexer.FileName = FileName;
Lexer.Mode = LexModeNormal;
Lexer.EmitExtraNewlines = 0;
Lexer.CharacterPos = 1;
Lexer.SourceText = Source;
return LexTokenise(&Lexer, TokenLen);
}
/* prepare to parse a pre-tokenised buffer */
void LexInitParser(struct ParseState *Parser, const char *SourceText, void *TokenSource, const char *FileName, int RunIt)
{
Parser->Pos = TokenSource;
Parser->Line = 1;
Parser->FileName = FileName;
Parser->Mode = RunIt ? RunModeRun : RunModeSkip;
Parser->SearchLabel = 0;
Parser->HashIfLevel = 0;
Parser->HashIfEvaluateToLevel = 0;
Parser->CharacterPos = 0;
Parser->SourceText = SourceText;
}
/* get the next token, without pre-processing */
enum LexToken LexGetRawToken(struct ParseState *Parser, struct Value **Value, int IncPos)
{
enum LexToken Token = TokenNone;
int ValueSize;
char *Prompt = NULL;
do
{
/* get the next token */
if (Parser->Pos == NULL && InteractiveHead != NULL)
Parser->Pos = InteractiveHead->Tokens;
if (Parser->FileName != StrEmpty || InteractiveHead != NULL)
{
/* skip leading newlines */
while ((Token = (enum LexToken)*(unsigned char *)Parser->Pos) == TokenEndOfLine)
{
Parser->Line++;
Parser->Pos += TOKEN_DATA_OFFSET;
}
}
if (Parser->FileName == StrEmpty && (InteractiveHead == NULL || Token == TokenEOF))
{
/* we're at the end of an interactive input token list */
char LineBuffer[LINEBUFFER_MAX];
void *LineTokens;
int LineBytes;
struct TokenLine *LineNode;
if (InteractiveHead == NULL || (unsigned char *)Parser->Pos == &InteractiveTail->Tokens[InteractiveTail->NumBytes-TOKEN_DATA_OFFSET])
{
/* get interactive input */
if (LexUseStatementPrompt)
{
Prompt = INTERACTIVE_PROMPT_STATEMENT;
LexUseStatementPrompt = FALSE;
}
else
Prompt = INTERACTIVE_PROMPT_LINE;
if (PlatformGetLine(&LineBuffer[0], LINEBUFFER_MAX, Prompt) == NULL)
return TokenEOF;
/* put the new line at the end of the linked list of interactive lines */
LineTokens = LexAnalyse(StrEmpty, &LineBuffer[0], strlen(LineBuffer), &LineBytes);
LineNode = VariableAlloc(Parser, sizeof(struct TokenLine), TRUE);
LineNode->Tokens = LineTokens;
LineNode->NumBytes = LineBytes;
if (InteractiveHead == NULL)
{
/* start a new list */
InteractiveHead = LineNode;
Parser->Line = 1;
Parser->CharacterPos = 0;
}
else
InteractiveTail->Next = LineNode;
InteractiveTail = LineNode;
InteractiveCurrentLine = LineNode;
Parser->Pos = LineTokens;
}
else
{
/* go to the next token line */
if (Parser->Pos != &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes-TOKEN_DATA_OFFSET])
{
/* scan for the line */
for (InteractiveCurrentLine = InteractiveHead; Parser->Pos != &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes-TOKEN_DATA_OFFSET]; InteractiveCurrentLine = InteractiveCurrentLine->Next)
{ assert(InteractiveCurrentLine->Next != NULL); }
}
assert(InteractiveCurrentLine != NULL);
InteractiveCurrentLine = InteractiveCurrentLine->Next;
assert(InteractiveCurrentLine != NULL);
Parser->Pos = InteractiveCurrentLine->Tokens;
}
Token = (enum LexToken)*(unsigned char *)Parser->Pos;
}
} while ((Parser->FileName == StrEmpty && Token == TokenEOF) || Token == TokenEndOfLine);
Parser->CharacterPos = *((unsigned char *)Parser->Pos + 1);
ValueSize = LexTokenSize(Token);
if (ValueSize > 0)
{
/* this token requires a value - unpack it */
if (Value != NULL)
{
switch (Token)
{
case TokenStringConstant: LexValue.Typ = CharPtrType; break;
case TokenIdentifier: LexValue.Typ = NULL; break;
case TokenIntegerConstant: LexValue.Typ = &IntType; break;
case TokenCharacterConstant: LexValue.Typ = &CharType; break;
#ifndef NO_FP
case TokenFPConstant: LexValue.Typ = &FPType; break;
#endif
default: break;
}
memcpy((void *)LexValue.Val, (void *)((char *)Parser->Pos + TOKEN_DATA_OFFSET), ValueSize);
LexValue.ValOnHeap = FALSE;
LexValue.ValOnStack = FALSE;
LexValue.IsLValue = FALSE;
LexValue.LValueFrom = NULL;
*Value = &LexValue;
}
if (IncPos)
Parser->Pos += ValueSize + TOKEN_DATA_OFFSET;
}
else
{
if (IncPos && Token != TokenEOF)
Parser->Pos += TOKEN_DATA_OFFSET;
}
#ifdef DEBUG_LEXER
printf("Got token=%02x inc=%d pos=%d\n", Token, IncPos, Parser->CharacterPos);
#endif
assert(Token >= TokenNone && Token <= TokenEndOfFunction);
return Token;
}
/* correct the token position depending if we already incremented the position */
void LexHashIncPos(struct ParseState *Parser, int IncPos)
{
if (!IncPos)
LexGetRawToken(Parser, NULL, TRUE);
}
/* handle a #ifdef directive */
void LexHashIfdef(struct ParseState *Parser, int IfNot)
{
/* get symbol to check */
struct Value *IdentValue;
struct Value *SavedValue;
int IsDefined;
enum LexToken Token = LexGetRawToken(Parser, &IdentValue, TRUE);
if (Token != TokenIdentifier)
ProgramFail(Parser, "identifier expected");
/* is the identifier defined? */
IsDefined = TableGet(&GlobalTable, IdentValue->Val->Identifier, &SavedValue, NULL, NULL, NULL);
if (Parser->HashIfEvaluateToLevel == Parser->HashIfLevel && ( (IsDefined && !IfNot) || (!IsDefined && IfNot)) )
{
/* #if is active, evaluate to this new level */
Parser->HashIfEvaluateToLevel++;
}
Parser->HashIfLevel++;
}
/* handle a #if directive */
void LexHashIf(struct ParseState *Parser)
{
/* get symbol to check */
struct Value *IdentValue = NULL;
struct Value *SavedValue = NULL;
struct ParseState MacroParser;
enum LexToken Token = LexGetRawToken(Parser, &IdentValue, TRUE);
if (Token == TokenIdentifier)
{
/* look up a value from a macro definition */
if (!TableGet(&GlobalTable, IdentValue->Val->Identifier, &SavedValue, NULL, NULL, NULL))
ProgramFail(Parser, "'%s' is undefined", IdentValue->Val->Identifier);
if (SavedValue->Typ->Base != TypeMacro)
ProgramFail(Parser, "value expected");
ParserCopy(&MacroParser, &SavedValue->Val->MacroDef.Body);
Token = LexGetRawToken(&MacroParser, &IdentValue, TRUE);
}
if (Token != TokenCharacterConstant)
ProgramFail(Parser, "value expected");
/* is the identifier defined? */
if (Parser->HashIfEvaluateToLevel == Parser->HashIfLevel && IdentValue->Val->Character)
{
/* #if is active, evaluate to this new level */
Parser->HashIfEvaluateToLevel++;
}
Parser->HashIfLevel++;
}
/* handle a #else directive */
void LexHashElse(struct ParseState *Parser)
{
if (Parser->HashIfEvaluateToLevel == Parser->HashIfLevel - 1)
Parser->HashIfEvaluateToLevel++; /* #if was not active, make this next section active */
else if (Parser->HashIfEvaluateToLevel == Parser->HashIfLevel)
{
/* #if was active, now go inactive */
if (Parser->HashIfLevel == 0)
ProgramFail(Parser, "#else without #if");
Parser->HashIfEvaluateToLevel--;
}
}
/* handle a #endif directive */
void LexHashEndif(struct ParseState *Parser)
{
if (Parser->HashIfLevel == 0)
ProgramFail(Parser, "#endif without #if");
Parser->HashIfLevel--;
if (Parser->HashIfEvaluateToLevel > Parser->HashIfLevel)
Parser->HashIfEvaluateToLevel = Parser->HashIfLevel;
}
/* get the next token given a parser state, pre-processing as we go */
enum LexToken LexGetToken(struct ParseState *Parser, struct Value **Value, int IncPos)
{
enum LexToken Token;
int TryNextToken;
/* implements the pre-processor #if commands */
do
{
int WasPreProcToken = TRUE;
Token = LexGetRawToken(Parser, Value, IncPos);
switch (Token)
{
case TokenHashIfdef: LexHashIncPos(Parser, IncPos); LexHashIfdef(Parser, FALSE); break;
case TokenHashIfndef: LexHashIncPos(Parser, IncPos); LexHashIfdef(Parser, TRUE); break;
case TokenHashIf: LexHashIncPos(Parser, IncPos); LexHashIf(Parser); break;
case TokenHashElse: LexHashIncPos(Parser, IncPos); LexHashElse(Parser); break;
case TokenHashEndif: LexHashIncPos(Parser, IncPos); LexHashEndif(Parser); break;
default: WasPreProcToken = FALSE; break;
}
/* if we're going to reject this token, increment the token pointer to the next one */
TryNextToken = (Parser->HashIfEvaluateToLevel < Parser->HashIfLevel && Token != TokenEOF) || WasPreProcToken;
if (!IncPos && TryNextToken)
LexGetRawToken(Parser, NULL, TRUE);
} while (TryNextToken);
return Token;
}
/* take a quick peek at the next token, skipping any pre-processing */
enum LexToken LexRawPeekToken(struct ParseState *Parser)
{
return (enum LexToken)*(unsigned char *)Parser->Pos;
}
/* find the end of the line */
void LexToEndOfLine(struct ParseState *Parser)
{
while (TRUE)
{
enum LexToken Token = (enum LexToken)*(unsigned char *)Parser->Pos;
if (Token == TokenEndOfLine || Token == TokenEOF)
return;
else
LexGetRawToken(Parser, NULL, TRUE);
}
}
/* copy the tokens from StartParser to EndParser into new memory, removing TokenEOFs and terminate with a TokenEndOfFunction */
void *LexCopyTokens(struct ParseState *StartParser, struct ParseState *EndParser)
{
int MemSize = 0;
int CopySize;
unsigned char *Pos = (unsigned char *)StartParser->Pos;
unsigned char *NewTokens;
unsigned char *NewTokenPos;
struct TokenLine *ILine;
if (InteractiveHead == NULL)
{
/* non-interactive mode - copy the tokens */
MemSize = EndParser->Pos - StartParser->Pos;
NewTokens = VariableAlloc(StartParser, MemSize + TOKEN_DATA_OFFSET, TRUE);
memcpy(NewTokens, (void *)StartParser->Pos, MemSize);
}
else
{
/* we're in interactive mode - add up line by line */
for (InteractiveCurrentLine = InteractiveHead; InteractiveCurrentLine != NULL && (Pos < &InteractiveCurrentLine->Tokens[0] || Pos >= &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes]); InteractiveCurrentLine = InteractiveCurrentLine->Next)
{} /* find the line we just counted */
if (EndParser->Pos >= StartParser->Pos && EndParser->Pos < &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes])
{
/* all on a single line */
MemSize = EndParser->Pos - StartParser->Pos;
NewTokens = VariableAlloc(StartParser, MemSize + TOKEN_DATA_OFFSET, TRUE);
memcpy(NewTokens, (void *)StartParser->Pos, MemSize);
}
else
{
/* it's spread across multiple lines */
MemSize = &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes-TOKEN_DATA_OFFSET] - Pos;
for (ILine = InteractiveCurrentLine->Next; ILine != NULL && (EndParser->Pos < &ILine->Tokens[0] || EndParser->Pos >= &ILine->Tokens[ILine->NumBytes]); ILine = ILine->Next)
MemSize += ILine->NumBytes - TOKEN_DATA_OFFSET;
assert(ILine != NULL);
MemSize += EndParser->Pos - &ILine->Tokens[0];
NewTokens = VariableAlloc(StartParser, MemSize + TOKEN_DATA_OFFSET, TRUE);
CopySize = &InteractiveCurrentLine->Tokens[InteractiveCurrentLine->NumBytes-TOKEN_DATA_OFFSET] - Pos;
memcpy(NewTokens, Pos, CopySize);
NewTokenPos = NewTokens + CopySize;
for (ILine = InteractiveCurrentLine->Next; ILine != NULL && (EndParser->Pos < &ILine->Tokens[0] || EndParser->Pos >= &ILine->Tokens[ILine->NumBytes]); ILine = ILine->Next)
{
memcpy(NewTokenPos, &ILine->Tokens[0], ILine->NumBytes - TOKEN_DATA_OFFSET);
NewTokenPos += ILine->NumBytes-TOKEN_DATA_OFFSET;
}
assert(ILine != NULL);
memcpy(NewTokenPos, &ILine->Tokens[0], EndParser->Pos - &ILine->Tokens[0]);
}
}
NewTokens[MemSize] = (unsigned char)TokenEndOfFunction;
return NewTokens;
}
/* indicate that we've completed up to this point in the interactive input and free expired tokens */
void LexInteractiveClear(struct ParseState *Parser)
{
while (InteractiveHead != NULL)
{
struct TokenLine *NextLine = InteractiveHead->Next;
HeapFreeMem(InteractiveHead->Tokens);
HeapFreeMem(InteractiveHead);
InteractiveHead = NextLine;
}
if (Parser != NULL)
Parser->Pos = NULL;
InteractiveTail = NULL;
}
/* indicate that we've completed up to this point in the interactive input and free expired tokens */
void LexInteractiveCompleted(struct ParseState *Parser)
{
while (InteractiveHead != NULL && !(Parser->Pos >= &InteractiveHead->Tokens[0] && Parser->Pos < &InteractiveHead->Tokens[InteractiveHead->NumBytes]))
{
/* this token line is no longer needed - free it */
struct TokenLine *NextLine = InteractiveHead->Next;
HeapFreeMem(InteractiveHead->Tokens);
HeapFreeMem(InteractiveHead);
InteractiveHead = NextLine;
if (InteractiveHead == NULL)
{
/* we've emptied the list */
Parser->Pos = NULL;
InteractiveTail = NULL;
}
}
}
/* the next time we prompt, make it the full statement prompt */
void LexInteractiveStatementPrompt()
{
LexUseStatementPrompt = TRUE;
}
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