heimdal/lib/krb5/config_file.y

%{

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

#include "krb5_locl.h"
#include "config_file.h"

RCSID("$Id$");

static char section[128];
static FILE *F;

static k5_cfile *cf;

static krb5_config_section *csec;

static krb5_config_relation **crel;
static krb5_config_relation **rels[16];
static int relp;

static void yyerror (char *);
static int yylex (void);

%}

%union {
	int	i;
	char   *s;
}

%token <s> STRING

%%

file	:  section_list
	;

section_list : /* empty */
	| section rel_list section_list 
		{ 
#ifdef DEBUG
			printf("section_list\n"); 
#endif
		}
	;

section
	: '[' STRING ']' 
	{
		krb5_config_section *p;
		p = ALLOC(1, krb5_config_section);
		p->next = NULL;
		p->name = $2;
		p->relations = NULL;
		if(cf->sections)
			p->next = cf->sections;
		cf->sections = p;
		csec = p;
		crel = &p->relations;
#ifdef DEBUG
		printf("section\n");
#endif
		strcpy(section, $2); 
	}
	;

rel_list 
	: relation rel_sub
	;

rel_sub	: /* empty */ 
	| relation rel_sub 
	;

relation
	: tag '=' value 
	{ 
#ifdef DEBUG
		printf("relation\n");
#endif
	}
	;

tag	: STRING 
	{	
		krb5_config_relation *p;
		if(!crel){
			fprintf(stderr, "error\n");
			return -17;
		}
		p = ALLOC(1, krb5_config_relation);
		p->tag = $1;
		if(*crel){
			p->next = NULL;
			(*crel)->value.data.relations = p;
			rels[relp++] = crel;
			crel = &p;
		}else{
			p->next = *crel;
			*crel = p;
		}
#ifdef DEBUG
		printf("tag\n"); 
#endif
	}
	;

value	: STRING
	{
		(*crel)->value.type = krb5_config_value_string;
		(*crel)->value.data.string = $1;
		crel = &(*crel)->next;
#ifdef DEBUG
		printf("value/string\n");
#endif
	}
	| '{' rel_list '}'
	{
		crel = rels[--relp];
		(*crel)->value.type = krb5_config_value_list;
		crel = &(*crel)->next;
#ifdef DEBUG
		printf("value/list\n");
#endif
	}
	;

%%

static int yylex(void)
{
    int c;
    static char save;
    static char yytext[1024];
    char *p = yytext;
    int type = 0;
    while(1){
	if(save){
	    c = save;
	    save = 0;
	}else
	    c = getc(F);
	if(c == EOF)
	    break;
	if(isspace(c))
	    if(type)
		break; /* end of token */
	    else 
		continue; /* eat ws */
	if(strchr("[]={}", c)){
	    if(type)
		save = c;
	    else{
		return c;
	    }
	    break;
	}
	*p++ = c;
	type = STRING;
	continue;
    }
    *p = 0;
    yylval.s = strdup(yytext);
    return type;
}

void yyerror(char *s)
{
    printf("yyerror: %s\n", s);
}


/*----------------------------------------*/

static void
free_config_file(k5_cfile *cf)
{
    if(!cf)
	return;
    FREE(cf->filename);
    free(cf);
}

static void free_config_relation(krb5_config_relation *rel);

static void
free_config_value(krb5_config_value val)
{
    if(val.type == krb5_config_value_string)
	FREE(val.data.string);
    else if(val.type == krb5_config_value_list)
	free_config_relation(val.data.relations);
    else
	fprintf(stderr, "free_config_value: krb5_config_value "
		"with bad type passed (%d)\n", val.type);
}

static void
free_config_relation(krb5_config_relation *rel)
{
    if(!rel)
	return;
    free_config_value(rel->value);
    free_config_relation(rel->next);
    FREE(rel);
}

static void
free_config_section(krb5_config_section *sec)
{
    if(!sec)
	return;
    FREE(sec->name);
    free_config_relation(sec->relations);
    free_config_section(sec->next);
    FREE(sec);
}


void
krb5_free_config_file(k5_cfile *cf)
{
    free_config_file(cf);
}

krb5_error_code
krb5_get_config_tag(k5_cfile *cf, const char *tag, char **value)
{
    char *str;
    char *p;
    krb5_config_section *s;
    krb5_config_relation *r;
  
    str = strdup(tag);
    p = strtok(str, " \t");
    if(!p)
	return KRB5_REALM_UNKNOWN;
    for(s = cf->sections; s; s = s->next){
	if(!strcmp(s->name, p)){
	    p = strtok(NULL, " \t");
	    for(r = s->relations; r;){
		if(!strcmp(r->tag, p)){
		    if(r->value.type == krb5_config_value_string){
			*value = strdup(r->value.data.string);
			free(str);
			return 0;
		    }else{
			p = strtok(NULL, " \t");
			r = r->value.data.relations;
			continue;
		    }
		}
		r = r->next;
	    }
	}
    }
    return KRB5_REALM_UNKNOWN;
}

krb5_error_code
krb5_parse_config_file(k5_cfile **cfile, const char *filename)
{
    krb5_error_code ret;
    if(!filename)
	filename = krb5_config_file;
    F = fopen(filename, "r");
    if(F == NULL)
	return errno;
    cf = ALLOC(1, k5_cfile);
    if(!cf)
	return ENOMEM;
    ret = yyparse();

    fclose(F);
    if(ret)
	krb5_free_config_file(cf);
    else
	*cfile = cf;
    return ret;
}