parser.c

bind 9.3结合mysql数据库

	for (;;) {
		cfg_listelt_t *elt;

	redo:
		/*
		 * Parse the option name and see if it is known.
		 */
		CHECK(cfg_gettoken(pctx, 0));

		if (pctx->token.type != isc_tokentype_string) {
			cfg_ungettoken(pctx);
			break;
		}

		/*
		 * We accept "include" statements wherever a map body
		 * clause can occur.
		 */
		if (strcasecmp(TOKEN_STRING(pctx), "include") == 0) {
			/*
			 * Turn the file name into a temporary configuration
			 * object just so that it is not overwritten by the
			 * semicolon token.
			 */
			CHECK(cfg_parse_obj(pctx, &cfg_type_qstring, &includename));
			CHECK(parse_semicolon(pctx));
			CHECK(parser_openfile(pctx, includename->
					      value.string.base));
			 cfg_obj_destroy(pctx, &includename);
			 goto redo;
		}

		clause = NULL;
		for (clauseset = clausesets; *clauseset != NULL; clauseset++) {
			for (clause = *clauseset;
			     clause->name != NULL;
			     clause++) {
				if (strcasecmp(TOKEN_STRING(pctx),
					   clause->name) == 0)
					goto done;
			}
		}
	done:
		if (clause == NULL || clause->name == NULL) {
			cfg_parser_error(pctx, CFG_LOG_NOPREP, "unknown option");
			/*
			 * Try to recover by parsing this option as an unknown
			 * option and discarding it.
			 */
			CHECK(cfg_parse_obj(pctx, &cfg_type_unsupported, &eltobj));
			cfg_obj_destroy(pctx, &eltobj);
			CHECK(parse_semicolon(pctx));
			continue;
		}

		/* Clause is known. */

		/* Issue warnings if appropriate */
		if ((clause->flags & CFG_CLAUSEFLAG_OBSOLETE) != 0)
			cfg_parser_warning(pctx, 0, "option '%s' is obsolete",
				       clause->name);
		if ((clause->flags & CFG_CLAUSEFLAG_NOTIMP) != 0)
			cfg_parser_warning(pctx, 0, "option '%s' is "
				       "not implemented", clause->name);
		if ((clause->flags & CFG_CLAUSEFLAG_NYI) != 0)
			cfg_parser_warning(pctx, 0, "option '%s' is "
				       "not implemented", clause->name);
		/*
		 * Don't log options with CFG_CLAUSEFLAG_NEWDEFAULT
		 * set here - we need to log the *lack* of such an option,
		 * not its presence.
		 */

		/* See if the clause already has a value; if not create one. */
		result = isc_symtab_lookup(obj->value.map.symtab,
					   clause->name, 0, &symval);

		if ((clause->flags & CFG_CLAUSEFLAG_MULTI) != 0) {
			/* Multivalued clause */
			cfg_obj_t *listobj = NULL;
			if (result == ISC_R_NOTFOUND) {
				CHECK(cfg_create_list(pctx,
						  &cfg_type_implicitlist,
						  &listobj));
				symval.as_pointer = listobj;
				result = isc_symtab_define(obj->value.
						   map.symtab,
						   clause->name,
						   1, symval,
						   isc_symexists_reject);
				if (result != ISC_R_SUCCESS) {
					cfg_parser_error(pctx, CFG_LOG_NEAR,
						     "isc_symtab_define(%s) "
						     "failed", clause->name);
					isc_mem_put(pctx->mctx, list,
						    sizeof(cfg_list_t));
					goto cleanup;
				}
			} else {
				INSIST(result == ISC_R_SUCCESS);
				listobj = symval.as_pointer;
			}

			elt = NULL;
			CHECK(cfg_parse_listelt(pctx, clause->type, &elt));
			CHECK(parse_semicolon(pctx));

			ISC_LIST_APPEND(listobj->value.list, elt, link);
		} else {
			/* Single-valued clause */
			if (result == ISC_R_NOTFOUND) {
				isc_boolean_t callback =
					ISC_TF((clause->flags &
						CFG_CLAUSEFLAG_CALLBACK) != 0);
				CHECK(parse_symtab_elt(pctx, clause->name,
						       clause->type,
						       obj->value.map.symtab,
						       callback));
				CHECK(parse_semicolon(pctx));
			} else if (result == ISC_R_SUCCESS) {
				cfg_parser_error(pctx, CFG_LOG_NEAR, "'%s' redefined",
					     clause->name);
				result = ISC_R_EXISTS;
				goto cleanup;
			} else {
				cfg_parser_error(pctx, CFG_LOG_NEAR,
					     "isc_symtab_define() failed");
				goto cleanup;
			}
		}
	}


	*ret = obj;
	return (ISC_R_SUCCESS);

 cleanup:
	CLEANUP_OBJ(value);
	CLEANUP_OBJ(obj);
	CLEANUP_OBJ(eltobj);
	CLEANUP_OBJ(includename);
	return (result);
}

static isc_result_t
parse_symtab_elt(cfg_parser_t *pctx, const char *name,
		 cfg_type_t *elttype, isc_symtab_t *symtab,
		 isc_boolean_t callback)
{
	isc_result_t result;
	cfg_obj_t *obj = NULL;
	isc_symvalue_t symval;

	CHECK(cfg_parse_obj(pctx, elttype, &obj));

	if (callback && pctx->callback != NULL)
		CHECK(pctx->callback(name, obj, pctx->callbackarg));
	
	symval.as_pointer = obj;
	CHECK(isc_symtab_define(symtab, name,
				1, symval,
				isc_symexists_reject));
	return (ISC_R_SUCCESS);

 cleanup:
	CLEANUP_OBJ(obj);
	return (result);
}

/*
 * Parse a map; e.g., "{ foo 1; bar { glub; }; zap true; zap false; }"
 */
isc_result_t
cfg_parse_map(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
	isc_result_t result;
	CHECK(cfg_parse_special(pctx, '{'));
	CHECK(cfg_parse_mapbody(pctx, type, ret));
	CHECK(cfg_parse_special(pctx, '}'));
 cleanup:
	return (result);
}

/*
 * Subroutine for cfg_parse_named_map() and cfg_parse_addressed_map().
 */
static isc_result_t
parse_any_named_map(cfg_parser_t *pctx, cfg_type_t *nametype, const cfg_type_t *type,
		    cfg_obj_t **ret)
{
	isc_result_t result;
	cfg_obj_t *idobj = NULL;
	cfg_obj_t *mapobj = NULL;

	CHECK(cfg_parse_obj(pctx, nametype, &idobj));
	CHECK(cfg_parse_map(pctx, type, &mapobj));
	mapobj->value.map.id = idobj;
	idobj = NULL;
	*ret = mapobj;
 cleanup:
	CLEANUP_OBJ(idobj);
	return (result);
}

/*
 * Parse a map identified by a string name.  E.g., "name { foo 1; }".  
 * Used for the "key" and "channel" statements.
 */
isc_result_t
cfg_parse_named_map(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
	return (parse_any_named_map(pctx, &cfg_type_astring, type, ret));
}

/*
 * Parse a map identified by a network address.
 * Used for the "server" statement.
 */
isc_result_t
cfg_parse_addressed_map(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
	return (parse_any_named_map(pctx, &cfg_type_netaddr, type, ret));
}

void
cfg_print_mapbody(cfg_printer_t *pctx, cfg_obj_t *obj) {
	isc_result_t result = ISC_R_SUCCESS;

	const cfg_clausedef_t * const *clauseset;

	for (clauseset = obj->value.map.clausesets;
	     *clauseset != NULL;
	     clauseset++)
	{
		isc_symvalue_t symval;
		const cfg_clausedef_t *clause;

		for (clause = *clauseset;
		     clause->name != NULL;
		     clause++) {
			result = isc_symtab_lookup(obj->value.map.symtab,
						   clause->name, 0, &symval);
			if (result == ISC_R_SUCCESS) {
				cfg_obj_t *obj = symval.as_pointer;
				if (obj->type == &cfg_type_implicitlist) {
					/* Multivalued. */
					cfg_list_t *list = &obj->value.list;
					cfg_listelt_t *elt;
					for (elt = ISC_LIST_HEAD(*list);
					     elt != NULL;
					     elt = ISC_LIST_NEXT(elt, link)) {
						print_indent(pctx);
						cfg_print_cstr(pctx, clause->name);
						cfg_print_chars(pctx, " ", 1);
						cfg_print_obj(pctx, elt->obj);
						cfg_print_chars(pctx, ";\n", 2);
					}
				} else {
					/* Single-valued. */
					print_indent(pctx);
					cfg_print_cstr(pctx, clause->name);
					cfg_print_chars(pctx, " ", 1);
					cfg_print_obj(pctx, obj);
					cfg_print_chars(pctx, ";\n", 2);
				}
			} else if (result == ISC_R_NOTFOUND) {
				; /* do nothing */
			} else {
				INSIST(0);
			}
		}
	}
}

void
cfg_doc_mapbody(cfg_printer_t *pctx, const cfg_type_t *type) {
	const cfg_clausedef_t * const *clauseset;
	const cfg_clausedef_t *clause;
	
	for (clauseset = type->of; *clauseset != NULL; clauseset++) {
		for (clause = *clauseset;
		     clause->name != NULL;
		     clause++) {
			cfg_print_cstr(pctx, clause->name);
			cfg_print_chars(pctx, " ", 1);
			cfg_doc_obj(pctx, clause->type);
			cfg_print_chars(pctx, ";", 1);
			/* XXX print flags here? */
			cfg_print_chars(pctx, "\n\n", 2);
		}
	}
}

static struct flagtext {
	unsigned int flag;
	const char *text;
} flagtexts[] = {
	{ CFG_CLAUSEFLAG_NOTIMP, "not implemented" },
	{ CFG_CLAUSEFLAG_NYI, "not yet implemented" },
	{ CFG_CLAUSEFLAG_OBSOLETE, "obsolete" },
	{ CFG_CLAUSEFLAG_NEWDEFAULT, "default changed" },
	{ 0, NULL }
};

void
cfg_print_map(cfg_printer_t *pctx, cfg_obj_t *obj) {
	if (obj->value.map.id != NULL) {
		cfg_print_obj(pctx, obj->value.map.id);
		cfg_print_chars(pctx, " ", 1);
	}
	print_open(pctx);
	cfg_print_mapbody(pctx, obj);
	print_close(pctx);
}

static void
print_clause_flags(cfg_printer_t *pctx, unsigned int flags) {
	struct flagtext *p;
	isc_boolean_t first = ISC_TRUE;
	for (p = flagtexts; p->flag != 0; p++) {
		if ((flags & p->flag) != 0) {
			if (first)
				cfg_print_chars(pctx, " // ", 4);
			else
				cfg_print_chars(pctx, ", ", 2);
			cfg_print_cstr(pctx, p->text);
			first = ISC_FALSE;
		}
	}
}

void
cfg_doc_map(cfg_printer_t *pctx, const cfg_type_t *type) {
	const cfg_clausedef_t * const *clauseset;
	const cfg_clausedef_t *clause;
	
	if (type->parse == cfg_parse_named_map) {
		cfg_doc_obj(pctx, &cfg_type_astring);
		cfg_print_chars(pctx, " ", 1);
	} else if (type->parse == cfg_parse_addressed_map) {
		cfg_doc_obj(pctx, &cfg_type_netaddr);
		cfg_print_chars(pctx, " ", 1);
	}
	
	print_open(pctx);
	
	for (clauseset = type->of; *clauseset != NULL; clauseset++) {
		for (clause = *clauseset;
		     clause->name != NULL;
		     clause++) {
			print_indent(pctx);
			cfg_print_cstr(pctx, clause->name);
			if (clause->type->print != cfg_print_void)
				cfg_print_chars(pctx, " ", 1);
			cfg_doc_obj(pctx, clause->type);
			cfg_print_chars(pctx, ";", 1);
			print_clause_flags(pctx, clause->flags);
			cfg_print_chars(pctx, "\n", 1);
		}
	}
	print_close(pctx);
}

isc_boolean_t
cfg_obj_ismap(cfg_obj_t *obj) {
	REQUIRE(obj != NULL);
	return (ISC_TF(obj->type->rep == &cfg_rep_map));
}

isc_result_t
cfg_map_get(cfg_obj_t *mapobj, const char* name, cfg_obj_t **obj) {
	isc_result_t result;
	isc_symvalue_t val;
	cfg_map_t *map;
	
	REQUIRE(mapobj != NULL && mapobj->type->rep == &cfg_rep_map);
	REQUIRE(name != NULL);
	REQUIRE(obj != NULL && *obj == NULL);

	map = &mapobj->value.map;
	
	result = isc_symtab_lookup(map->symtab, name, MAP_SYM, &val);
	if (result != ISC_R_SUCCESS)
		return (result);
	*obj = val.as_pointer;
	return (ISC_R_SUCCESS);
}

cfg_obj_t *
cfg_map_getname(cfg_obj_t *mapobj) {
	REQUIRE(mapobj != NULL && mapobj->type->rep == &cfg_rep_map);
	return (mapobj->value.map.id);
}


/* Parse an arbitrary token, storing its raw text representation. */
static isc_result_t
parse_token(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
	cfg_obj_t *obj = NULL;
        isc_result_t result;
	isc_region_t r;

	UNUSED(type);

	CHECK(cfg_create_obj(pctx, &cfg_type_token, &obj));
	CHECK(cfg_gettoken(pctx, CFG_LEXOPT_QSTRING));
	if (pctx->token.type == isc_tokentype_eof) {
		cfg_ungettoken(pctx);
		result = ISC_R_EOF;
		goto cleanup;
	}

	isc_lex_getlasttokentext(pctx->lexer, &pctx->token, &r);

	obj->value.string.base = isc_mem_get(pctx->mctx, r.length + 1);
	obj->value.string.length = r.length;
	memcpy(obj->value.string.base, r.base, r.length);
	obj->value.string.base[r.length] = '\0';
	*ret = obj;

 cleanup:
	return (result);
}

cfg_type_t cfg_type_token = {
	"token", parse_token, cfg_print_ustring, cfg_doc_terminal,
	&cfg_rep_string, NULL
};

/*
 * An unsupported option.  This is just a list of tokens with balanced braces
 * ending in a semicolon.
 */

static isc_result_t
parse_unsupported(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
	cfg_obj_t *listobj = NULL;
	isc_result_t result;
	int braces = 0;

	CHECK(cfg_create_list(pctx, type, &listobj));

	for (;;) {
		cfg_listelt_t *elt = NULL;

		CHECK(cfg_peektoken(pctx, 0));
		if (pctx->token.type == isc_tokentype_special) {
			if (pctx->token.value.as_char == '{')
				braces++;
			else if (pctx->token.value.as_char == '}')
				braces--;
			else if (pctx->token.value.as_char == ';')
				if (braces == 0)
					break;
		}
		if (pctx->token.type == isc_tokentype_eof || braces < 0) {
			cfg_parser_error(pctx, CFG_LOG_NEAR, "unexpected token");
			result = ISC_R_UNEXPECTEDTOKEN;
			goto cleanup;
		}

		CHECK(cfg_parse_listelt(pctx, &cfg_type_token, &elt));
		ISC_LIST_APPEND(listobj->value.list, elt, link);
	}
	INSIST(braces == 0);
	*ret = listobj;
	return (ISC_R_SUCCESS);

 cleanup:
	CLEANUP_OBJ(listobj);
	return (result);
}

cfg_type_t cfg_type_unsupported = {
	"unsupported", parse_unsupported, cfg_print_spacelist, cfg_doc_terminal,
	&cfg_rep_list, NULL
};

/*
 * Try interpreting the current token as a network address.
 *
 * If CFG_ADDR_WILDOK is set in flags, "*" can be used as a wildcard
 * and at least one of CFG_ADDR_V4OK and CFG_ADDR_V6OK must also be set.  The
 * "*" is interpreted as the IPv4 wildcard address if CFG_ADDR_V4OK is 
 * set (including the case where CFG_ADDR_V4OK and CFG_ADDR_V6OK are both set),
 * and the IPv6 wildcard address otherwise.
 */
static isc_result_t
token_addr(cfg_parser_t *pctx, unsigned int flags, isc_netaddr_t *na) {
	char *s;
	struct in_addr in4a;
	struct in6_addr in6a;

	if (pctx->token.type != isc_tokentype_string)
		return (ISC_R_UNEXPECTEDTOKEN);

	s = TOKEN_STRING(pctx);
	if ((flags & CFG_ADDR_WILDOK) != 0 && strcmp(s, "*") == 0) {
		if ((flags & CFG_ADDR_V4OK) != 0) {
			isc_netaddr_any(na);
			return (ISC_R_SUCCESS);
		} else if ((flags & CFG_ADDR_V6OK) != 0) {
			isc_netaddr_any6(na);
			return (ISC_R_SUCCESS);
		} else {
			INSIST(0);
		}
	} else {
		if ((flags & (CFG_ADDR_V4OK | CFG_ADDR_V4PREFIXOK)) != 0) {
			if (inet_pton(AF_INET, s, &in4a) == 1) {
				isc_netaddr_fromin(na, &in4a);
				return (ISC_R_SUCCESS);
			}
		}
		if ((flags & CFG_ADDR_V4PREFIXOK) != 0 &&
		    strlen(s) <= 15U) {
			char buf[64];
			int i;

			strcpy(buf, s);
			for (i = 0; i < 3; i++) {
				strcat(buf, ".0");
				if (inet_pton(AF_INET, buf, &in4a) == 1) {
					isc_netaddr_fromin(na, &in4a);
					return (ISC_R_SUCCESS);
				}
			}
		}
		if ((flags & CFG_ADDR_V6OK) != 0 &&
		    strlen(s) <= 127U) {
			char buf[128]; /* see lib/bind9/getaddresses.c */
			char *d; /* zone delimiter */
			isc_uint32_t zone = 0; /* scope zone ID */

			strcpy(buf, s);
			d = strchr(buf, '%');
			if (d != NULL)
				*d = '\0';

			if (inet_pton(AF_INET6, buf, &in6a) == 1) {
				if (d != NULL) {
#ifdef ISC_PLATFORM_HAVESCOPEID
					isc_result_t result;

					result = isc_netscope_pton(AF_INET6,
								   d + 1,
								   &in6a,
								   &zone);
					if (result != ISC_R_SUCCESS)
						return (result);
#else
				return (ISC_R_BADADDRESSFORM);
#endif
				}

				isc_netaddr_fromin6(na, &in6a);
				isc_netaddr_setzone(na, zone);
				return (ISC_R_SUCCESS);
			}
		}
	}
	return (ISC_R_UNEXPECTEDTOKEN);
}

isc_result_t
cfg_parse_rawaddr(cfg_parser_t *pctx, unsigned int flags, isc_netaddr_t *na) {
	isc_result_t result;
	CHECK(cfg_gettoken(pctx, 0));
	result = token_addr(pctx, flags, na);
	if (result == ISC_R_UNEXPECTEDTOKEN)
		cfg_parser_error(pctx, CFG_LOG_NEAR, "expected IP address");
 cleanup:
	return (result);
}

isc_boolean_t