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/*
* Copyright (c) 2002-2005 The TenDRA Project <http://www.tendra.org/>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of The TenDRA Project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific, prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
* IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id$
*/
/*
Crown Copyright (c) 1997
This TenDRA(r) Computer Program is subject to Copyright
owned by the United Kingdom Secretary of State for Defence
acting through the Defence Evaluation and Research Agency
(DERA). It is made available to Recipients with a
royalty-free licence for its use, reproduction, transfer
to other parties and amendment for any purpose not excluding
product development provided that any such use et cetera
shall be deemed to be acceptance of the following conditions:-
(1) Its Recipients shall ensure that this Notice is
reproduced upon any copies or amended versions of it;
(2) Any amended version of it shall be clearly marked to
show both the nature of and the organisation responsible
for the relevant amendment or amendments;
(3) Its onward transfer from a recipient to another
party shall be deemed to be that party's acceptance of
these conditions;
(4) DERA gives no warranty or assurance as to its
quality or suitability for any purpose and DERA accepts
no liability whatsoever in relation to any use to which
it may be put.
*/
#include "config.h"
#include "errors.h"
#include "error.h"
#include "lex.h"
#include "syntax.h"
#include "xalloc.h"
/*
INPUT FILE
This is the file from which the lexical routine read their input.
*/
static FILE *lex_input;
/*
PENDING BUFFER
Pending characters are dealt with by means of this buffer. pending
is set to the start of the buffer to indicate that there are no
characters pending, otherwise the pending characters are stored in
the buffer. The buffer may need increasing in size if the look-ahead
required by the lexical analyser increases.
*/
static int pending_buff[12] = {'?'};
static int *pending = pending_buff;
/*
MAPPINGS AND DECLARATIONS FOR AUTOMATICALLY GENERATED SECTION
These macros give the mappings between the actions used in the
automatically generated lexical analyser and the routines defined
in this file.
*/
static int read_char(void);
static int read_comment(void);
static int read_identifier(int);
static int read_string(void);
#define get_comment(A, B) read_comment()
#define get_identifier(A) read_identifier((A))
#define get_string(A) read_string()
#define unknown_token(A) lex_unknown
#define unread_char(A) *(++pending) = (A)
/*
AUTOMATICALLY GENERATED SECTION
The main body of the lexical analyser is automatically generated.
*/
#include "lexer.h"
/*
GET THE NEXT CHARACTER
This routine reads the next character, either from the pending buffer
or from the input file.
*/
static int
read_char(void)
{
int c;
if (pending != pending_buff) {
c = *(pending--);
} else {
c = fgetc(lex_input);
if (c == '\n') {
crt_line_no++;
}
if (c == EOF) {
return (LEX_EOF);
}
c &= 0xff;
}
return (c);
}
/*
TOKEN BUFFER
This buffer is used by read_token to hold the values of identifiers
and strings.
*/
char token_buff[2000];
static char *token_end = token_buff + sizeof(token_buff);
char *first_comment = NULL;
/*
READ AN IDENTIFIER
This routine reads an identifier beginning with a, returning the
corresponding lexical token. Keywords are dealt with locally.
*/
static int
read_identifier(int a)
{
int c = a, cl;
char *t = token_buff;
do {
*(t++) = (char) c;
if (t == token_end) {
error(ERROR_FATAL, "Buffer overflow");
}
c = read_char();
cl = lookup_char(c);
} while (is_alphanum(cl));
*t = 0;
unread_char(c);
/* Deal with keywords */
t = token_buff;
#define MAKE_KEYWORD(A, B)\
if (streq(t,(A))) return (B);
#include "keyword.h"
return (lex_identifier);
}
/*
READ A STRING
This routine reads a string. It is entered after the initial quote has
been read. Note that new line characters are allowed in strings.
*/
static int
read_string(void)
{
int c;
int escaped = 0;
char *t = token_buff;
while (c = read_char(),(c != '"' || escaped)) {
if (c == LEX_EOF) {
error(ERROR_SERIOUS, "Unexpected end of string");
break;
}
*(t++) = (char) c;
if (t == token_end) {
error(ERROR_FATAL, "Buffer overflow");
}
if (escaped) {
escaped = 0;
} else {
if (c == '\\') {
escaped = 1;
}
}
}
*t = 0;
return (lex_string);
}
/*
READ A COMMENT
This routine reads a C style comment, returning the lexical token
immediately following. It is entered after the first two characters
have been read.
*/
static int
read_comment(void)
{
int state = 0;
char *t = token_buff;
*(t++) = '/';
*(t++) = '*';
while (state != 2) {
int c = read_char();
if (c == LEX_EOF) {
error(ERROR_SERIOUS, "End of file in comment");
return (lex_eof);
}
if (c == '*') {
state = 1;
} else if (state == 1 && c == '/') {
state = 2;
} else {
state = 0;
}
*(t++) = (char) c;
if (t == token_end) {
t = token_buff + 2;
}
}
if (first_comment == NULL) {
first_comment = xstrcpy(token_buff);
}
return (read_token());
}
/*
CURRENT TOKEN
These variables are used by the parser to hold the current and former
lexical tokens.
*/
int crt_lex_token;
int saved_lex_token;
/*
PROCESS FILE
This routine processes the input file nm. If nm is the null string
then the standard input is used.
*/
void
process_file(char *nm)
{
crt_line_no = 1;
if (nm == NULL || streq(nm, "-")) {
crt_file_name = "stdin";
lex_input = stdin;
nm = NULL;
} else {
crt_file_name = nm;
lex_input = fopen(nm, "r");
if (lex_input == NULL) {
error(ERROR_SERIOUS, "Can't open input file, '%s'", nm);
return;
}
}
ADVANCE_LEXER;
read_errors();
if (nm != NULL) {
fclose_v(lex_input);
}
return;
}