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%option noyywrap
%{
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "symbol-table.h"
#define SIZE_OF_ARR(x) (sizeof(x)/sizeof(x[0]))
int line_number = 1;
%}
letter [A-Za-z]
digit [0-9]
ID {letter}({letter}|{digit}|"_")*
WS [ \t]+
/* You need to define the following RE's */
CONST_INT {digit}+
CONST_FLOAT (([0-9]+\.?|[0-9]*\.[0-9]+)([eE][-+]?[0-9]+)?)
CONST_STRING \"([^\"\n]|(\\.))*\"
COMMENT \/\*([^*]|\n|(\*+([^*/]|\n)))*\*+\/
/* operators */
OP_ASSIGN "="
OP_OR "||"
OP_AND "&&"
OP_NOT "!"
OP_ADD "+"
OP_SUB "-"
OP_MUL "*"
OP_DIV "/"
OP_GT ">"
OP_LT "<"
OP_GE ">="
OP_LE "<="
OP_NE "!="
OP_EQ "=="
NEWLINE "\n"
/* separators */
DL_LPAREN "("
DL_RPAREN ")"
DL_LBRACK "["
DL_RBRACK "]"
DL_LBRACE "{"
DL_RBRACE "}"
DL_COMMA ","
DL_SEMICOL ";"
DL_DOT "."
ERROR .
%%
{WS} {}
{ID} {
int i;
char *reserved[] = {"return", "typedef", "if", "else",
"int", "float", "for", "void", "while"};
enum yytokentype reserved_token[] = {RETURN, TYPEDEF,
IF, ELSE, INT, FLOAT, FOR, VOID, WHILE};
static_assert(
SIZE_OF_ARR(reserved) == SIZE_OF_ARR(reserved_token),
"Reserved words array and reserved tokens array "
"must have the same size");
for (i = 0; i < SIZE_OF_ARR(reserved); i++)
if (strcmp(yytext, reserved[i]) == 0)
return reserved_token[i];
if (i == SIZE_OF_ARR(reserved)) {
CcmmcSymbol * ptr;
ptr = ccmmc_symbol_table_lookup(yytext);
if (ptr == NULL)
ccmmc_symbol_table_insert_id(yytext, line_number);
else
ptr->counter++;
}
yylval.lexeme = strdup(yytext);
if (yylval.lexeme == NULL) {
fputs("strdup() failed\n", stderr);
exit(1);
}
return ID;
}
{CONST_INT} {
CON_Type *p;
p = (CON_Type *)malloc(sizeof(CON_Type));
p->const_type = INTEGERC;
p->const_u.intval = atoi(yytext);
yylval.const1 = p;
return CONST;
}
{CONST_FLOAT} {
CON_Type *p;
p = (CON_Type *)malloc(sizeof(CON_Type));
p->const_type = FLOATC;
p->const_u.fval = atof(yytext);
yylval.const1 = p;
return CONST;
}
{CONST_STRING} {
CON_Type *p;
p = (CON_Type *)malloc(sizeof(CON_Type));
p->const_type = STRINGC;
p->const_u.sc = strdup(yytext);
yylval.const1 = p;
return CONST;
}
{COMMENT} {
int i;
for (i = 0; yytext[i]; i++)
if (yytext[i] == '\n')
line_number++;
}
{OP_ASSIGN} return OP_ASSIGN;
{OP_OR} return OP_OR;
{OP_AND} return OP_AND;
{OP_NOT} return OP_NOT;
{OP_ADD} return OP_ADD;
{OP_SUB} return OP_SUB;
{OP_MUL} return OP_MUL;
{OP_DIV} return OP_DIV;
{OP_GT} return OP_GT;
{OP_LT} return OP_LT;
{OP_GE} return OP_GE;
{OP_LE} return OP_LE;
{OP_NE} return OP_NE;
{OP_EQ} return OP_EQ;
{NEWLINE} line_number++;
{DL_LPAREN} return DL_LPAREN;
{DL_RPAREN} return DL_RPAREN;
{DL_LBRACK} return DL_LBRACK;
{DL_RBRACK} return DL_RBRACK;
{DL_LBRACE} return DL_LBRACE;
{DL_RBRACE} return DL_RBRACE;
{DL_COMMA} return DL_COMMA;
{DL_SEMICOL} return DL_SEMICOL;
{DL_DOT} return DL_DOT;
{ERROR} {
fprintf(stderr, "%d: error: undefined character `%s'\n",
line_number, yytext);
exit(1);
}
%%
// vim: set sw=4 ts=4 sts=4 et:
|
