Commit 82fc7be7 authored by Martin Mareš's avatar Martin Mareš

Lexical analyser.

parent fe7cec12
/*
* BIRD -- Configuration Lexer
*
* (c) 1998 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
%{
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "nest/bird.h"
#include "conf/conf.h"
#include "conf/cf-parse.tab.h"
static struct keyword {
byte *name;
int value;
struct keyword *next;
} keyword_list[] = {
#include "keywords.h"
{ NULL, -1 } };
#define KW_HASH_SIZE 64
#define SYM_HASH_SIZE 128
#define SYM_MAX_LEN 32
static struct keyword *kw_hash[KW_HASH_SIZE];
static struct symbol **sym_hash;
static int allow_new_symbols;
static int cf_lino;
static int cf_hash(byte *c);
static struct symbol *cf_find_sym(byte *c, unsigned int h0);
pool *cfg_pool;
mempool *cfg_mem;
int (*cf_read_hook)(byte *buf, unsigned int max);
#define YY_INPUT(buf,result,max) result = cf_read_hook(buf, max);
#define YY_NO_UNPUT
#define YY_FATAL_ERROR(msg) cf_error(msg)
%}
%option noyywrap
%x COMMENT CCOMM
ALPHA [a-zA-Z_]
DIGIT [0-9]
XIGIT [0-9a-fA-F]
ALNUM [a-zA-Z_0-9]
WHITE [ \t]
%%
{DIGIT}+\.{DIGIT}+\.{DIGIT}+\.{DIGIT}+ {
if (ip_pton(yytext, &cf_lval.a))
return IPA;
cf_error("Invalid IP address");
}
0x{DIGIT}+ {
char *e;
long int l;
errno = 0;
l = strtoul(yytext+2, &e, 16);
if (e && *e || errno == ERANGE || (long int)(int) l != l)
cf_error("Number out of range");
cf_lval.i = l;
return NUM;
}
{DIGIT}+ {
char *e;
long int l;
errno = 0;
l = strtoul(yytext, &e, 10);
if (e && *e || errno == ERANGE || (long int)(int) l != l)
cf_error("Number out of range");
cf_lval.i = l;
return NUM;
}
{ALPHA}{ALNUM}* {
unsigned int h = cf_hash(yytext);
struct keyword *k = kw_hash[h & (KW_HASH_SIZE-1)];
while (k)
{
if (!strcmp(k->name, yytext))
return k->value;
k=k->next;
}
cf_lval.s = cf_find_sym(yytext, h);
return SYM;
}
[{}:;,] {
return yytext[0];
}
["][^"\n]*["] {
cf_lval.t = yytext+1;
yytext[yyleng] = 0;
return TEXT;
}
["][^"\n]*\n cf_error("Unterminated string");
<INITIAL,COMMENT><<EOF>> return END;
{WHITE}+
\\\n {
cf_lino++;
}
\n {
cf_lino++;
return ';';
}
# { BEGIN(COMMENT); }
\/\* { BEGIN(CCOMM); }
. cf_error("Unknown character");
<COMMENT>\n {
cf_lino++;
BEGIN(INITIAL);
}
<COMMENT>.
<CCOMM>\*\/ BEGIN(INITIAL);
<CCOMM>\n cf_lino++;
<CCOMM>\/\* cf_error("Comment nesting not supported");
<CCOMM><<EOF>> cf_error("Unterminated comment");
<CCOMM>.
%%
static int
cf_hash(byte *c)
{
unsigned int h = 13;
while (*c)
h = (h * 37) + *c++;
return h;
}
static struct symbol *
cf_find_sym(byte *c, unsigned int h0)
{
unsigned int h = h0 & (SYM_HASH_SIZE-1);
struct symbol *s = sym_hash[h];
int l;
while (s)
if (!strcmp(s->name, c))
return s;
if (!allow_new_symbols)
return NULL;
l = strlen(c);
if (l > SYM_MAX_LEN)
cf_error("Symbol too long");
s = mp_alloc(cfg_mem, sizeof(struct symbol) + l);
s->next = sym_hash[h];
sym_hash[h] = s;
s->class = SYM_VOID;
s->def = NULL;
strcpy(s->name, c);
return s;
}
void
cf_lex_init(int flag)
{
if (allow_new_symbols = flag)
sym_hash = mp_allocz(cfg_mem, SYM_HASH_SIZE * sizeof(struct keyword *));
cf_lino = 1;
}
void
cf_lex_init_tables(void)
{
struct keyword *k;
for(k=keyword_list; k->name; k++)
{
unsigned h = cf_hash(k->name) & (KW_HASH_SIZE-1);
k->next = kw_hash[h];
kw_hash[h] = k;
}
}
void
cf_error(char *msg)
{
die(PATH_CONFIG ", line %d: %s", cf_lino, msg);
}
void
cf_allocate(void)
{
if (cfg_pool)
rfree(cfg_pool);
cfg_pool = rp_new(&root_pool, "Config");
cfg_mem = mp_new(cfg_pool, 1024);
}
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