/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
%{
#include <stdio.h>
#include <stdlib.h>
#include "ast.h"
#include "lexer.h"
#include "parser.h"
const char *tokenToString(int token)
{
static char scratch[128];
switch (token) {
case TOK_AND:
return "&&";
case TOK_OR:
return "||";
case TOK_EQ:
return "==";
case TOK_NE:
return "!=";
case TOK_GE:
return ">=";
case TOK_LE:
return "<=";
case TOK_EOF:
return "EOF";
case TOK_EOL:
return "EOL\n";
case TOK_STRING:
snprintf(scratch, sizeof(scratch),
"STRING<%s>", yylval.literalString);
return scratch;
case TOK_IDENTIFIER:
snprintf(scratch, sizeof(scratch), "IDENTIFIER<%s>",
yylval.literalString);
return scratch;
case TOK_WORD:
snprintf(scratch, sizeof(scratch), "WORD<%s>",
yylval.literalString);
return scratch;
default:
if (token > ' ' && token <= '~') {
scratch[0] = (char)token;
scratch[1] = '\0';
} else {
snprintf(scratch, sizeof(scratch), "??? <%d>", token);
}
return scratch;
}
}
typedef struct {
char *value;
char *nextc;
unsigned int alloc_size;
} AmString;
static int addCharToString(AmString *str, char c)
{
if ((unsigned int)(str->nextc - str->value) >= str->alloc_size) {
char *new_value;
unsigned int new_size;
new_size = (str->alloc_size + 1) * 2;
if (new_size < 64) {
new_size = 64;
}
new_value = (char *)realloc(str->value, new_size);
if (new_value == NULL) {
yyerror("out of memory");
return -1;
}
str->nextc = str->nextc - str->value + new_value;
str->value = new_value;
str->alloc_size = new_size;
}
*str->nextc++ = c;
return 0;
}
static int setString(AmString *str, const char *p)
{
str->nextc = str->value;
while (*p != '\0') {
//TODO: add the whole string at once
addCharToString(str, *p++);
}
return addCharToString(str, '\0');
}
static AmString gStr = { NULL, NULL, 0 };
static int gLineNumber = 1;
static AmArgumentType gArgumentType = AM_UNKNOWN_ARGS;
static const char *gErrorMessage = NULL;
#if AMEND_LEXER_BUFFER_INPUT
static const char *gInputBuffer;
static const char *gInputBufferNext;
static const char *gInputBufferEnd;
# define YY_INPUT(buf, result, max_size) \
do { \
int nbytes = gInputBufferEnd - gInputBufferNext; \
if (nbytes > 0) { \
if (nbytes > max_size) { \
nbytes = max_size; \
} \
memcpy(buf, gInputBufferNext, nbytes); \
gInputBufferNext += nbytes; \
result = nbytes; \
} else { \
result = YY_NULL; \
} \
} while (false)
#endif // AMEND_LEXER_BUFFER_INPUT
%}
%option noyywrap
%x QUOTED_STRING BOOLEAN WORDS
ident [a-zA-Z_][a-zA-Z_0-9]*
word [^ \t\r\n"]+
%%
/* This happens at the beginning of each call to yylex().
*/
if (gArgumentType == AM_WORD_ARGS) {
BEGIN(WORDS);
} else if (gArgumentType == AM_BOOLEAN_ARGS) {
BEGIN(BOOLEAN);
}
/*xxx require everything to be 7-bit-clean, printable characters */
<INITIAL>{
{ident}/[ \t\r\n] {
/* The only token we recognize in the initial
* state is an identifier followed by whitespace.
*/
setString(&gStr, yytext);
yylval.literalString = gStr.value;
return TOK_IDENTIFIER;
}
}
<BOOLEAN>{
{ident} {
/* Non-quoted identifier-style string */
setString(&gStr, yytext);
yylval.literalString = gStr.value;
return TOK_IDENTIFIER;
}
"&&" return TOK_AND;
"||" return TOK_OR;
"==" return TOK_EQ;
"!=" return TOK_NE;
">=" return TOK_GE;
"<=" return TOK_LE;
[<>()!,] return yytext[0];
}
/* Double-quoted string handling */
<WORDS,BOOLEAN>\" {
/* Initial quote */
gStr.nextc = gStr.value;
BEGIN(QUOTED_STRING);
}
<QUOTED_STRING>{
\" {
/* Closing quote */
BEGIN(INITIAL);
addCharToString(&gStr, '\0');
yylval.literalString = gStr.value;
if (gArgumentType == AM_WORD_ARGS) {
return TOK_WORD;
} else {
return TOK_STRING;
}
}
<<EOF>> |
\n {
/* Unterminated string */
yyerror("unterminated string");
return TOK_ERROR;
}
\\\" {
/* Escaped quote */
addCharToString(&gStr, '"');
}
\\\\ {
/* Escaped backslash */
addCharToString(&gStr, '\\');
}
\\. {
/* No other escapes allowed. */
gErrorMessage = "illegal escape";
return TOK_ERROR;
}
[^\\\n\"]+ {
/* String contents */
char *p = yytext;
while (*p != '\0') {
/* TODO: add the whole string at once */
addCharToString(&gStr, *p++);
}
}
}
<WORDS>{
/*xxx look out for backslashes; escape backslashes and quotes */
/*xxx if a quote is right against a char, we should append */
{word} {
/* Whitespace-separated word */
setString(&gStr, yytext);
yylval.literalString = gStr.value;
return TOK_WORD;
}
}
<INITIAL,WORDS,BOOLEAN>{
\n {
/* Count lines */
gLineNumber++;
gArgumentType = AM_UNKNOWN_ARGS;
BEGIN(INITIAL);
return TOK_EOL;
}
/*xxx backslashes to extend lines? */
/* Skip whitespace and comments.
*/
[ \t\r]+ ;
#.* ;
. {
/* Fail on anything we didn't expect. */
gErrorMessage = "unexpected character";
return TOK_ERROR;
}
}
%%
void
yyerror(const char *msg)
{
if (!strcmp(msg, "syntax error") && gErrorMessage != NULL) {
msg = gErrorMessage;
gErrorMessage = NULL;
}
fprintf(stderr, "line %d: %s at '%s'\n", gLineNumber, msg, yytext);
}
#if AMEND_LEXER_BUFFER_INPUT
void
setLexerInputBuffer(const char *buf, size_t buflen)
{
gLineNumber = 1;
gInputBuffer = buf;
gInputBufferNext = gInputBuffer;
gInputBufferEnd = gInputBuffer + buflen;
}
#endif // AMEND_LEXER_BUFFER_INPUT
void
setLexerArgumentType(AmArgumentType type)
{
gArgumentType = type;
}
int
getLexerLineNumber(void)
{
return gLineNumber;
}
