lib/isccfg/parser.c

	parser.c revision b8d4e96e95fc9f5f0d799a6f5579ca30b6adeb1e
/*
 * Copyright (C) 2004-2010  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2000-2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* $Id: parser.c,v 1.134 2010/06/23 23:46:58 tbox Exp $ */

/*! \file */

#include <config.h>

#include <isc/buffer.h>
#include <isc/dir.h>
#include <isc/formatcheck.h>
#include <isc/lex.h>
#include <isc/log.h>
#include <isc/mem.h>
#include <isc/net.h>
#include <isc/netaddr.h>
#include <isc/netscope.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/sockaddr.h>
#include <isc/symtab.h>
#include <isc/util.h>

#include <isccfg/cfg.h>
#include <isccfg/grammar.h>
#include <isccfg/log.h>

/* Shorthand */
#define CAT CFG_LOGCATEGORY_CONFIG
#define MOD CFG_LOGMODULE_PARSER

#define MAP_SYM 1   /* Unique type for isc_symtab */

#define TOKEN_STRING(pctx) (pctx->token.value.as_textregion.base)

/* Check a return value. */
#define CHECK(op)                       \
    do { result = (op);                     \
        if (result != ISC_R_SUCCESS) goto cleanup;  \
    } while (0)

/* Clean up a configuration object if non-NULL. */
#define CLEANUP_OBJ(obj) \
    do { if ((obj) != NULL) cfg_obj_destroy(pctx, &(obj)); } while (0)


/*
 * Forward declarations of static functions.
 */

static void
free_tuple(cfg_parser_t *pctx, cfg_obj_t *obj);

static isc_result_t
parse_list(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret);

static void
print_list(cfg_printer_t *pctx, const cfg_obj_t *obj);

static void
free_list(cfg_parser_t *pctx, cfg_obj_t *obj);

static isc_result_t
create_listelt(cfg_parser_t *pctx, cfg_listelt_t **eltp);

static isc_result_t
create_string(cfg_parser_t *pctx, const char *contents, const cfg_type_t *type,
          cfg_obj_t **ret);

static void
free_string(cfg_parser_t *pctx, cfg_obj_t *obj);

static isc_result_t
create_map(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **objp);

static void
free_map(cfg_parser_t *pctx, cfg_obj_t *obj);

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);

static void
free_noop(cfg_parser_t *pctx, cfg_obj_t *obj);

static isc_result_t
cfg_getstringtoken(cfg_parser_t *pctx);

static void
parser_complain(cfg_parser_t *pctx, isc_boolean_t is_warning,
        unsigned int flags, const char *format, va_list args);

/*
 * Data representations.  These correspond to members of the
 * "value" union in struct cfg_obj (except "void", which does
 * not need a union member).
 */

cfg_rep_t cfg_rep_uint32 = { "uint32", free_noop };
cfg_rep_t cfg_rep_uint64 = { "uint64", free_noop };
cfg_rep_t cfg_rep_string = { "string", free_string };
cfg_rep_t cfg_rep_boolean = { "boolean", free_noop };
cfg_rep_t cfg_rep_map = { "map", free_map };
cfg_rep_t cfg_rep_list = { "list", free_list };
cfg_rep_t cfg_rep_tuple = { "tuple", free_tuple };
cfg_rep_t cfg_rep_sockaddr = { "sockaddr", free_noop };
cfg_rep_t cfg_rep_netprefix = { "netprefix", free_noop };
cfg_rep_t cfg_rep_void = { "void", free_noop };

/*
 * Configuration type definitions.
 */

/*%
 * An implicit list.  These are formed by clauses that occur multiple times.
 */
static cfg_type_t cfg_type_implicitlist = {
    "implicitlist", NULL, print_list, NULL, &cfg_rep_list, NULL };

/* Functions. */

void
cfg_print_obj(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    obj->type->print(pctx, obj);
}

void
cfg_print_chars(cfg_printer_t *pctx, const char *text, int len) {
    pctx->f(pctx->closure, text, len);
}

static void
print_open(cfg_printer_t *pctx) {
    cfg_print_chars(pctx, "{\n", 2);
    pctx->indent++;
}

static void
print_indent(cfg_printer_t *pctx) {
    int indent = pctx->indent;
    while (indent > 0) {
        cfg_print_chars(pctx, "\t", 1);
        indent--;
    }
}

static void
print_close(cfg_printer_t *pctx) {
    pctx->indent--;
    print_indent(pctx);
    cfg_print_chars(pctx, "}", 1);
}

isc_result_t
cfg_parse_obj(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    INSIST(ret != NULL && *ret == NULL);
    result = type->parse(pctx, type, ret);
    if (result != ISC_R_SUCCESS)
        return (result);
    INSIST(*ret != NULL);
    return (ISC_R_SUCCESS);
}

void
cfg_print(const cfg_obj_t *obj,
      void (*f)(void *closure, const char *text, int textlen),
      void *closure)
{
    cfg_printer_t pctx;
    pctx.f = f;
    pctx.closure = closure;
    pctx.indent = 0;
    obj->type->print(&pctx, obj);
}


/* Tuples. */

isc_result_t
cfg_create_tuple(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    const cfg_tuplefielddef_t *fields = type->of;
    const cfg_tuplefielddef_t *f;
    cfg_obj_t *obj = NULL;
    unsigned int nfields = 0;
    int i;

    for (f = fields; f->name != NULL; f++)
        nfields++;

    CHECK(cfg_create_obj(pctx, type, &obj));
    obj->value.tuple = isc_mem_get(pctx->mctx,
                       nfields * sizeof(cfg_obj_t *));
    if (obj->value.tuple == NULL) {
        result = ISC_R_NOMEMORY;
        goto cleanup;
    }
    for (f = fields, i = 0; f->name != NULL; f++, i++)
        obj->value.tuple[i] = NULL;
    *ret = obj;
    return (ISC_R_SUCCESS);

 cleanup:
    if (obj != NULL)
        isc_mem_put(pctx->mctx, obj, sizeof(*obj));
    return (result);
}

isc_result_t
cfg_parse_tuple(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret)
{
    isc_result_t result;
    const cfg_tuplefielddef_t *fields = type->of;
    const cfg_tuplefielddef_t *f;
    cfg_obj_t *obj = NULL;
    unsigned int i;

    CHECK(cfg_create_tuple(pctx, type, &obj));
    for (f = fields, i = 0; f->name != NULL; f++, i++)
        CHECK(cfg_parse_obj(pctx, f->type, &obj->value.tuple[i]));

    *ret = obj;
    return (ISC_R_SUCCESS);

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

void
cfg_print_tuple(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    unsigned int i;
    const cfg_tuplefielddef_t *fields = obj->type->of;
    const cfg_tuplefielddef_t *f;
    isc_boolean_t need_space = ISC_FALSE;

    for (f = fields, i = 0; f->name != NULL; f++, i++) {
        const cfg_obj_t *fieldobj = obj->value.tuple[i];
        if (need_space)
            cfg_print_chars(pctx, " ", 1);
        cfg_print_obj(pctx, fieldobj);
        need_space = ISC_TF(fieldobj->type->print != cfg_print_void);
    }
}

void
cfg_doc_tuple(cfg_printer_t *pctx, const cfg_type_t *type) {
    const cfg_tuplefielddef_t *fields = type->of;
    const cfg_tuplefielddef_t *f;
    isc_boolean_t need_space = ISC_FALSE;

    for (f = fields; f->name != NULL; f++) {
        if (need_space)
            cfg_print_chars(pctx, " ", 1);
        cfg_doc_obj(pctx, f->type);
        need_space = ISC_TF(f->type->print != cfg_print_void);
    }
}

static void
free_tuple(cfg_parser_t *pctx, cfg_obj_t *obj) {
    unsigned int i;
    const cfg_tuplefielddef_t *fields = obj->type->of;
    const cfg_tuplefielddef_t *f;
    unsigned int nfields = 0;

    if (obj->value.tuple == NULL)
        return;

    for (f = fields, i = 0; f->name != NULL; f++, i++) {
        CLEANUP_OBJ(obj->value.tuple[i]);
        nfields++;
    }
    isc_mem_put(pctx->mctx, obj->value.tuple,
            nfields * sizeof(cfg_obj_t *));
}

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

const cfg_obj_t *
cfg_tuple_get(const cfg_obj_t *tupleobj, const char* name) {
    unsigned int i;
    const cfg_tuplefielddef_t *fields;
    const cfg_tuplefielddef_t *f;

    REQUIRE(tupleobj != NULL && tupleobj->type->rep == &cfg_rep_tuple);

    fields = tupleobj->type->of;
    for (f = fields, i = 0; f->name != NULL; f++, i++) {
        if (strcmp(f->name, name) == 0)
            return (tupleobj->value.tuple[i]);
    }
    INSIST(0);
    return (NULL);
}

isc_result_t
cfg_parse_special(cfg_parser_t *pctx, int special) {
    isc_result_t result;
    CHECK(cfg_gettoken(pctx, 0));
    if (pctx->token.type == isc_tokentype_special &&
        pctx->token.value.as_char == special)
        return (ISC_R_SUCCESS);

    cfg_parser_error(pctx, CFG_LOG_NEAR, "'%c' expected", special);
    return (ISC_R_UNEXPECTEDTOKEN);
 cleanup:
    return (result);
}

/*
 * Parse a required semicolon.  If it is not there, log
 * an error and increment the error count but continue
 * parsing.  Since the next token is pushed back,
 * care must be taken to make sure it is eventually
 * consumed or an infinite loop may result.
 */
static isc_result_t
parse_semicolon(cfg_parser_t *pctx) {
    isc_result_t result;
    CHECK(cfg_gettoken(pctx, 0));
    if (pctx->token.type == isc_tokentype_special &&
        pctx->token.value.as_char == ';')
        return (ISC_R_SUCCESS);

    cfg_parser_error(pctx, CFG_LOG_BEFORE, "missing ';'");
    cfg_ungettoken(pctx);
 cleanup:
    return (result);
}

/*
 * Parse EOF, logging and returning an error if not there.
 */
static isc_result_t
parse_eof(cfg_parser_t *pctx) {
    isc_result_t result;
    CHECK(cfg_gettoken(pctx, 0));

    if (pctx->token.type == isc_tokentype_eof)
        return (ISC_R_SUCCESS);

    cfg_parser_error(pctx, CFG_LOG_NEAR, "syntax error");
    return (ISC_R_UNEXPECTEDTOKEN);
 cleanup:
    return (result);
}

/* A list of files, used internally for pctx->files. */

static cfg_type_t cfg_type_filelist = {
    "filelist", NULL, print_list, NULL, &cfg_rep_list,
    &cfg_type_qstring
};

isc_result_t
cfg_parser_create(isc_mem_t *mctx, isc_log_t *lctx, cfg_parser_t **ret) {
    isc_result_t result;
    cfg_parser_t *pctx;
    isc_lexspecials_t specials;

    REQUIRE(mctx != NULL);
    REQUIRE(ret != NULL && *ret == NULL);

    pctx = isc_mem_get(mctx, sizeof(*pctx));
    if (pctx == NULL)
        return (ISC_R_NOMEMORY);

    pctx->mctx = mctx;
    pctx->lctx = lctx;
    pctx->lexer = NULL;
    pctx->seen_eof = ISC_FALSE;
    pctx->ungotten = ISC_FALSE;
    pctx->errors = 0;
    pctx->warnings = 0;
    pctx->open_files = NULL;
    pctx->closed_files = NULL;
    pctx->line = 0;
    pctx->callback = NULL;
    pctx->callbackarg = NULL;
    pctx->token.type = isc_tokentype_unknown;
    pctx->flags = 0;

    memset(specials, 0, sizeof(specials));
    specials['{'] = 1;
    specials['}'] = 1;
    specials[';'] = 1;
    specials['/'] = 1;
    specials['"'] = 1;
    specials['!'] = 1;

    CHECK(isc_lex_create(pctx->mctx, 1024, &pctx->lexer));

    isc_lex_setspecials(pctx->lexer, specials);
    isc_lex_setcomments(pctx->lexer, (ISC_LEXCOMMENT_C |
                     ISC_LEXCOMMENT_CPLUSPLUS |
                     ISC_LEXCOMMENT_SHELL));

    CHECK(cfg_create_list(pctx, &cfg_type_filelist, &pctx->open_files));
    CHECK(cfg_create_list(pctx, &cfg_type_filelist, &pctx->closed_files));

    *ret = pctx;
    return (ISC_R_SUCCESS);

 cleanup:
    if (pctx->lexer != NULL)
        isc_lex_destroy(&pctx->lexer);
    CLEANUP_OBJ(pctx->open_files);
    CLEANUP_OBJ(pctx->closed_files);
    isc_mem_put(mctx, pctx, sizeof(*pctx));
    return (result);
}

static isc_result_t
parser_openfile(cfg_parser_t *pctx, const char *filename) {
    isc_result_t result;
    cfg_listelt_t *elt = NULL;
    cfg_obj_t *stringobj = NULL;

    result = isc_lex_openfile(pctx->lexer, filename);
    if (result != ISC_R_SUCCESS) {
        cfg_parser_error(pctx, 0, "open: %s: %s",
                 filename, isc_result_totext(result));
        goto cleanup;
    }

    CHECK(create_string(pctx, filename, &cfg_type_qstring, &stringobj));
    CHECK(create_listelt(pctx, &elt));
    elt->obj = stringobj;
    ISC_LIST_APPEND(pctx->open_files->value.list, elt, link);

    return (ISC_R_SUCCESS);
 cleanup:
    CLEANUP_OBJ(stringobj);
    return (result);
}

void
cfg_parser_setcallback(cfg_parser_t *pctx,
               cfg_parsecallback_t callback,
               void *arg)
{
    pctx->callback = callback;
    pctx->callbackarg = arg;
}

/*
 * Parse a configuration using a pctx where a lexer has already
 * been set up with a source.
 */
static isc_result_t
parse2(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    cfg_obj_t *obj = NULL;

    result = cfg_parse_obj(pctx, type, &obj);

    if (pctx->errors != 0) {
        /* Errors have been logged. */
        if (result == ISC_R_SUCCESS)
            result = ISC_R_FAILURE;
        goto cleanup;
    }

    if (result != ISC_R_SUCCESS) {
        /* Parsing failed but no errors have been logged. */
        cfg_parser_error(pctx, 0, "parsing failed");
        goto cleanup;
    }

    CHECK(parse_eof(pctx));

    *ret = obj;
    return (ISC_R_SUCCESS);

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

isc_result_t
cfg_parse_file(cfg_parser_t *pctx, const char *filename,
           const cfg_type_t *type, cfg_obj_t **ret)
{
    isc_result_t result;

    REQUIRE(filename != NULL);

    CHECK(parser_openfile(pctx, filename));
    CHECK(parse2(pctx, type, ret));
 cleanup:
    return (result);
}


isc_result_t
cfg_parse_buffer(cfg_parser_t *pctx, isc_buffer_t *buffer,
    const cfg_type_t *type, cfg_obj_t **ret)
{
    isc_result_t result;
    REQUIRE(buffer != NULL);
    CHECK(isc_lex_openbuffer(pctx->lexer, buffer));
    CHECK(parse2(pctx, type, ret));
 cleanup:
    return (result);
}

void
cfg_parser_destroy(cfg_parser_t **pctxp) {
    cfg_parser_t *pctx = *pctxp;
    isc_lex_destroy(&pctx->lexer);
    /*
     * Cleaning up open_files does not
     * close the files; that was already done
     * by closing the lexer.
     */
    CLEANUP_OBJ(pctx->open_files);
    CLEANUP_OBJ(pctx->closed_files);
    isc_mem_put(pctx->mctx, pctx, sizeof(*pctx));
    *pctxp = NULL;
}

/*
 * void
 */
isc_result_t
cfg_parse_void(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    UNUSED(type);
    return (cfg_create_obj(pctx, &cfg_type_void, ret));
}

void
cfg_print_void(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    UNUSED(pctx);
    UNUSED(obj);
}

void
cfg_doc_void(cfg_printer_t *pctx, const cfg_type_t *type) {
    UNUSED(pctx);
    UNUSED(type);
}

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

cfg_type_t cfg_type_void = {
    "void", cfg_parse_void, cfg_print_void, cfg_doc_void, &cfg_rep_void,
    NULL };


/*
 * uint32
 */
isc_result_t
cfg_parse_uint32(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    cfg_obj_t *obj = NULL;
    UNUSED(type);

    CHECK(cfg_gettoken(pctx, ISC_LEXOPT_NUMBER | ISC_LEXOPT_CNUMBER));
    if (pctx->token.type != isc_tokentype_number) {
        cfg_parser_error(pctx, CFG_LOG_NEAR, "expected number");
        return (ISC_R_UNEXPECTEDTOKEN);
    }

    CHECK(cfg_create_obj(pctx, &cfg_type_uint32, &obj));

    obj->value.uint32 = pctx->token.value.as_ulong;
    *ret = obj;
 cleanup:
    return (result);
}

void
cfg_print_cstr(cfg_printer_t *pctx, const char *s) {
    cfg_print_chars(pctx, s, strlen(s));
}

void
cfg_print_rawuint(cfg_printer_t *pctx, unsigned int u) {
    char buf[32];
    snprintf(buf, sizeof(buf), "%u", u);
    cfg_print_cstr(pctx, buf);
}

void
cfg_print_uint32(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    cfg_print_rawuint(pctx, obj->value.uint32);
}

isc_boolean_t
cfg_obj_isuint32(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL);
    return (ISC_TF(obj->type->rep == &cfg_rep_uint32));
}

isc_uint32_t
cfg_obj_asuint32(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_uint32);
    return (obj->value.uint32);
}

cfg_type_t cfg_type_uint32 = {
    "integer", cfg_parse_uint32, cfg_print_uint32, cfg_doc_terminal,
    &cfg_rep_uint32, NULL
};


/*
 * uint64
 */
isc_boolean_t
cfg_obj_isuint64(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL);
    return (ISC_TF(obj->type->rep == &cfg_rep_uint64));
}

isc_uint64_t
cfg_obj_asuint64(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_uint64);
    return (obj->value.uint64);
}

void
cfg_print_uint64(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    char buf[32];
    snprintf(buf, sizeof(buf), "%" ISC_PRINT_QUADFORMAT "u",
         obj->value.uint64);
    cfg_print_cstr(pctx, buf);
}

cfg_type_t cfg_type_uint64 = {
    "64_bit_integer", NULL, cfg_print_uint64, cfg_doc_terminal,
    &cfg_rep_uint64, NULL
};

/*
 * qstring (quoted string), ustring (unquoted string), astring
 * (any string)
 */

/* Create a string object from a null-terminated C string. */
static isc_result_t
create_string(cfg_parser_t *pctx, const char *contents, const cfg_type_t *type,
          cfg_obj_t **ret)
{
    isc_result_t result;
    cfg_obj_t *obj = NULL;
    int len;

    CHECK(cfg_create_obj(pctx, type, &obj));
    len = strlen(contents);
    obj->value.string.length = len;
    obj->value.string.base = isc_mem_get(pctx->mctx, len + 1);
    if (obj->value.string.base == 0) {
        isc_mem_put(pctx->mctx, obj, sizeof(*obj));
        return (ISC_R_NOMEMORY);
    }
    memcpy(obj->value.string.base, contents, len);
    obj->value.string.base[len] = '\0';

    *ret = obj;
 cleanup:
    return (result);
}

isc_result_t
cfg_parse_qstring(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    UNUSED(type);

    CHECK(cfg_gettoken(pctx, CFG_LEXOPT_QSTRING));
    if (pctx->token.type != isc_tokentype_qstring) {
        cfg_parser_error(pctx, CFG_LOG_NEAR, "expected quoted string");
        return (ISC_R_UNEXPECTEDTOKEN);
    }
    return (create_string(pctx,
                  TOKEN_STRING(pctx),
                  &cfg_type_qstring,
                  ret));
 cleanup:
    return (result);
}

static isc_result_t
parse_ustring(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    UNUSED(type);

    CHECK(cfg_gettoken(pctx, 0));
    if (pctx->token.type != isc_tokentype_string) {
        cfg_parser_error(pctx, CFG_LOG_NEAR, "expected unquoted string");
        return (ISC_R_UNEXPECTEDTOKEN);
    }
    return (create_string(pctx,
                  TOKEN_STRING(pctx),
                  &cfg_type_ustring,
                  ret));
 cleanup:
    return (result);
}

isc_result_t
cfg_parse_astring(cfg_parser_t *pctx, const cfg_type_t *type,
          cfg_obj_t **ret)
{
    isc_result_t result;
    UNUSED(type);

    CHECK(cfg_getstringtoken(pctx));
    return (create_string(pctx,
                  TOKEN_STRING(pctx),
                  &cfg_type_qstring,
                  ret));
 cleanup:
    return (result);
}

isc_boolean_t
cfg_is_enum(const char *s, const char *const *enums) {
    const char * const *p;
    for (p = enums; *p != NULL; p++) {
        if (strcasecmp(*p, s) == 0)
            return (ISC_TRUE);
    }
    return (ISC_FALSE);
}

static isc_result_t
check_enum(cfg_parser_t *pctx, cfg_obj_t *obj, const char *const *enums) {
    const char *s = obj->value.string.base;
    if (cfg_is_enum(s, enums))
        return (ISC_R_SUCCESS);
    cfg_parser_error(pctx, 0, "'%s' unexpected", s);
    return (ISC_R_UNEXPECTEDTOKEN);
}

isc_result_t
cfg_parse_enum(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    cfg_obj_t *obj = NULL;
    CHECK(parse_ustring(pctx, NULL, &obj));
    CHECK(check_enum(pctx, obj, type->of));
    *ret = obj;
    return (ISC_R_SUCCESS);
 cleanup:
    CLEANUP_OBJ(obj);
    return (result);
}

void
cfg_doc_enum(cfg_printer_t *pctx, const cfg_type_t *type) {
    const char * const *p;
    cfg_print_chars(pctx, "( ", 2);
    for (p = type->of; *p != NULL; p++) {
        cfg_print_cstr(pctx, *p);
        if (p[1] != NULL)
            cfg_print_chars(pctx, " | ", 3);
    }
    cfg_print_chars(pctx, " )", 2);
}

void
cfg_print_ustring(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    cfg_print_chars(pctx, obj->value.string.base, obj->value.string.length);
}

static void
print_qstring(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    cfg_print_chars(pctx, "\"", 1);
    cfg_print_ustring(pctx, obj);
    cfg_print_chars(pctx, "\"", 1);
}

static void
free_string(cfg_parser_t *pctx, cfg_obj_t *obj) {
    isc_mem_put(pctx->mctx, obj->value.string.base,
            obj->value.string.length + 1);
}

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

const char *
cfg_obj_asstring(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_string);
    return (obj->value.string.base);
}

/* Quoted string only */
cfg_type_t cfg_type_qstring = {
    "quoted_string", cfg_parse_qstring, print_qstring, cfg_doc_terminal,
    &cfg_rep_string, NULL
};

/* Unquoted string only */
cfg_type_t cfg_type_ustring = {
    "string", parse_ustring, cfg_print_ustring, cfg_doc_terminal,
    &cfg_rep_string, NULL
};

/* Any string (quoted or unquoted); printed with quotes */
cfg_type_t cfg_type_astring = {
    "string", cfg_parse_astring, print_qstring, cfg_doc_terminal,
    &cfg_rep_string, NULL
};

/*
 * Booleans
 */

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

isc_boolean_t
cfg_obj_asboolean(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_boolean);
    return (obj->value.boolean);
}

static isc_result_t
parse_boolean(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret)
{
    isc_result_t result;
    isc_boolean_t value;
    cfg_obj_t *obj = NULL;
    UNUSED(type);

    result = cfg_gettoken(pctx, 0);
    if (result != ISC_R_SUCCESS)
        return (result);

    if (pctx->token.type != isc_tokentype_string)
        goto bad_boolean;

    if ((strcasecmp(TOKEN_STRING(pctx), "true") == 0) ||
        (strcasecmp(TOKEN_STRING(pctx), "yes") == 0) ||
        (strcmp(TOKEN_STRING(pctx), "1") == 0)) {
        value = ISC_TRUE;
    } else if ((strcasecmp(TOKEN_STRING(pctx), "false") == 0) ||
           (strcasecmp(TOKEN_STRING(pctx), "no") == 0) ||
           (strcmp(TOKEN_STRING(pctx), "0") == 0)) {
        value = ISC_FALSE;
    } else {
        goto bad_boolean;
    }

    CHECK(cfg_create_obj(pctx, &cfg_type_boolean, &obj));
    obj->value.boolean = value;
    *ret = obj;
    return (result);

 bad_boolean:
    cfg_parser_error(pctx, CFG_LOG_NEAR, "boolean expected");
    return (ISC_R_UNEXPECTEDTOKEN);

 cleanup:
    return (result);
}

static void
print_boolean(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    if (obj->value.boolean)
        cfg_print_chars(pctx, "yes", 3);
    else
        cfg_print_chars(pctx, "no", 2);
}

cfg_type_t cfg_type_boolean = {
    "boolean", parse_boolean, print_boolean, cfg_doc_terminal,
    &cfg_rep_boolean, NULL
};

/*
 * Lists.
 */

isc_result_t
cfg_create_list(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **obj) {
    isc_result_t result;
    CHECK(cfg_create_obj(pctx, type, obj));
    ISC_LIST_INIT((*obj)->value.list);
 cleanup:
    return (result);
}

static isc_result_t
create_listelt(cfg_parser_t *pctx, cfg_listelt_t **eltp) {
    cfg_listelt_t *elt;
    elt = isc_mem_get(pctx->mctx, sizeof(*elt));
    if (elt == NULL)
        return (ISC_R_NOMEMORY);
    elt->obj = NULL;
    ISC_LINK_INIT(elt, link);
    *eltp = elt;
    return (ISC_R_SUCCESS);
}

static void
free_list_elt(cfg_parser_t *pctx, cfg_listelt_t *elt) {
    cfg_obj_destroy(pctx, &elt->obj);
    isc_mem_put(pctx->mctx, elt, sizeof(*elt));
}

static void
free_list(cfg_parser_t *pctx, cfg_obj_t *obj) {
    cfg_listelt_t *elt, *next;
    for (elt = ISC_LIST_HEAD(obj->value.list);
         elt != NULL;
         elt = next)
    {
        next = ISC_LIST_NEXT(elt, link);
        free_list_elt(pctx, elt);
    }
}

isc_result_t
cfg_parse_listelt(cfg_parser_t *pctx, const cfg_type_t *elttype,
          cfg_listelt_t **ret)
{
    isc_result_t result;
    cfg_listelt_t *elt = NULL;
    cfg_obj_t *value = NULL;

    CHECK(create_listelt(pctx, &elt));

    result = cfg_parse_obj(pctx, elttype, &value);
    if (result != ISC_R_SUCCESS)
        goto cleanup;

    elt->obj = value;

    *ret = elt;
    return (ISC_R_SUCCESS);

 cleanup:
    isc_mem_put(pctx->mctx, elt, sizeof(*elt));
    return (result);
}

/*
 * Parse a homogeneous list whose elements are of type 'elttype'
 * and where each element is terminated by a semicolon.
 */
static isc_result_t
parse_list(cfg_parser_t *pctx, const cfg_type_t *listtype, cfg_obj_t **ret)
{
    cfg_obj_t *listobj = NULL;
    const cfg_type_t *listof = listtype->of;
    isc_result_t result;
    cfg_listelt_t *elt = NULL;

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

    for (;;) {
        CHECK(cfg_peektoken(pctx, 0));
        if (pctx->token.type == isc_tokentype_special &&
            pctx->token.value.as_char == /*{*/ '}')
            break;
        CHECK(cfg_parse_listelt(pctx, listof, &elt));
        CHECK(parse_semicolon(pctx));
        ISC_LIST_APPEND(listobj->value.list, elt, link);
        elt = NULL;
    }
    *ret = listobj;
    return (ISC_R_SUCCESS);

 cleanup:
    if (elt != NULL)
        free_list_elt(pctx, elt);
    CLEANUP_OBJ(listobj);
    return (result);
}

static void
print_list(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    const cfg_list_t *list = &obj->value.list;
    const cfg_listelt_t *elt;

    for (elt = ISC_LIST_HEAD(*list);
         elt != NULL;
         elt = ISC_LIST_NEXT(elt, link)) {
        print_indent(pctx);
        cfg_print_obj(pctx, elt->obj);
        cfg_print_chars(pctx, ";\n", 2);
    }
}

isc_result_t
cfg_parse_bracketed_list(cfg_parser_t *pctx, const cfg_type_t *type,
             cfg_obj_t **ret)
{
    isc_result_t result;
    CHECK(cfg_parse_special(pctx, '{'));
    CHECK(parse_list(pctx, type, ret));
    CHECK(cfg_parse_special(pctx, '}'));
 cleanup:
    return (result);
}

void
cfg_print_bracketed_list(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    print_open(pctx);
    print_list(pctx, obj);
    print_close(pctx);
}

void
cfg_doc_bracketed_list(cfg_printer_t *pctx, const cfg_type_t *type) {
    cfg_print_chars(pctx, "{ ", 2);
    cfg_doc_obj(pctx, type->of);
    cfg_print_chars(pctx, "; ... }", 7);
}

/*
 * Parse a homogeneous list whose elements are of type 'elttype'
 * and where elements are separated by space.  The list ends
 * before the first semicolon.
 */
isc_result_t
cfg_parse_spacelist(cfg_parser_t *pctx, const cfg_type_t *listtype,
            cfg_obj_t **ret)
{
    cfg_obj_t *listobj = NULL;
    const cfg_type_t *listof = listtype->of;
    isc_result_t result;

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

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

        CHECK(cfg_peektoken(pctx, 0));
        if (pctx->token.type == isc_tokentype_special &&
            pctx->token.value.as_char == ';')
            break;
        CHECK(cfg_parse_listelt(pctx, listof, &elt));
        ISC_LIST_APPEND(listobj->value.list, elt, link);
    }
    *ret = listobj;
    return (ISC_R_SUCCESS);

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

void
cfg_print_spacelist(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    const cfg_list_t *list = &obj->value.list;
    const cfg_listelt_t *elt;

    for (elt = ISC_LIST_HEAD(*list);
         elt != NULL;
         elt = ISC_LIST_NEXT(elt, link)) {
        cfg_print_obj(pctx, elt->obj);
        if (ISC_LIST_NEXT(elt, link) != NULL)
            cfg_print_chars(pctx, " ", 1);
    }
}

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

const cfg_listelt_t *
cfg_list_first(const cfg_obj_t *obj) {
    REQUIRE(obj == NULL || obj->type->rep == &cfg_rep_list);
    if (obj == NULL)
        return (NULL);
    return (ISC_LIST_HEAD(obj->value.list));
}

const cfg_listelt_t *
cfg_list_next(const cfg_listelt_t *elt) {
    REQUIRE(elt != NULL);
    return (ISC_LIST_NEXT(elt, link));
}

/*
 * Return the length of a list object.  If obj is NULL or is not
 * a list, return 0.
 */
unsigned int
cfg_list_length(const cfg_obj_t *obj, isc_boolean_t recurse) {
    const cfg_listelt_t *elt;
    unsigned int count = 0;

    if (obj == NULL || !cfg_obj_islist(obj))
        return (0U);
    for (elt = cfg_list_first(obj);
         elt != NULL;
         elt = cfg_list_next(elt)) {
        if (recurse && cfg_obj_islist(elt->obj)) {
            count += cfg_list_length(elt->obj, recurse);
        } else {
            count++;
        }
    }
    return (count);
}

const cfg_obj_t *
cfg_listelt_value(const cfg_listelt_t *elt) {
    REQUIRE(elt != NULL);
    return (elt->obj);
}

/*
 * Maps.
 */

/*
 * Parse a map body.  That's something like
 *
 *   "foo 1; bar { glub; }; zap true; zap false;"
 *
 * i.e., a sequence of option names followed by values and
 * terminated by semicolons.  Used for the top level of
 * the named.conf syntax, as well as for the body of the
 * options, view, zone, and other statements.
 */
isc_result_t
cfg_parse_mapbody(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret)
{
    const cfg_clausedef_t * const *clausesets = type->of;
    isc_result_t result;
    const cfg_clausedef_t * const *clauseset;
    const cfg_clausedef_t *clause;
    cfg_obj_t *value = NULL;
    cfg_obj_t *obj = NULL;
    cfg_obj_t *eltobj = NULL;
    cfg_obj_t *includename = NULL;
    isc_symvalue_t symval;
    cfg_list_t *list = NULL;

    CHECK(create_map(pctx, type, &obj));

    obj->value.map.clausesets = clausesets;

    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);

        if ((clause->flags & CFG_CLAUSEFLAG_NOTCONFIGURED) != 0) {
            cfg_parser_warning(pctx, 0, "option '%s' is not "
                       "configured", clause->name);
            result = ISC_R_FAILURE;
            goto cleanup;
        }

        /*
         * 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 to be 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));
}

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

void
cfg_print_mapbody(cfg_printer_t *pctx, const 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" },
    { CFG_CLAUSEFLAG_TESTONLY, "test only" },
    { CFG_CLAUSEFLAG_NOTCONFIGURED, "not configured" },
    { 0, NULL }
};

void
cfg_print_map(cfg_printer_t *pctx, const 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);
    } else if (type->parse == cfg_parse_netprefix_map) {
        cfg_doc_obj(pctx, &cfg_type_netprefix);
        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(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL);
    return (ISC_TF(obj->type->rep == &cfg_rep_map));
}

isc_result_t
cfg_map_get(const cfg_obj_t *mapobj, const char* name, const cfg_obj_t **obj) {
    isc_result_t result;
    isc_symvalue_t val;
    const 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);
}

const cfg_obj_t *
cfg_map_getname(const 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);
    if (obj->value.string.base == NULL) {
        result = ISC_R_NOMEMORY;
        goto cleanup;
    }
    obj->value.string.length = r.length;
    memcpy(obj->value.string.base, r.base, r.length);
    obj->value.string.base[r.length] = '\0';
    *ret = obj;
    return (result);

 cleanup:
    if (obj != NULL)
        isc_mem_put(pctx->mctx, obj, sizeof(*obj));
    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;
    const char *wild = "";
    const char *prefix = "";

    CHECK(cfg_gettoken(pctx, 0));
    result = token_addr(pctx, flags, na);
    if (result == ISC_R_UNEXPECTEDTOKEN) {
        if ((flags & CFG_ADDR_WILDOK) != 0)
            wild = " or '*'";
        if ((flags & CFG_ADDR_V4PREFIXOK) != 0)
            wild = " or IPv4 prefix";
        if ((flags & CFG_ADDR_MASK) == CFG_ADDR_V4OK)
            cfg_parser_error(pctx, CFG_LOG_NEAR,
                     "expected IPv4 address%s%s",
                     prefix, wild);
        else if ((flags & CFG_ADDR_MASK) == CFG_ADDR_V6OK)
            cfg_parser_error(pctx, CFG_LOG_NEAR,
                     "expected IPv6 address%s%s",
                     prefix, wild);
        else
            cfg_parser_error(pctx, CFG_LOG_NEAR,
                     "expected IP address%s%s",
                     prefix, wild);
    }
 cleanup:
    return (result);
}

isc_boolean_t
cfg_lookingat_netaddr(cfg_parser_t *pctx, unsigned int flags) {
    isc_result_t result;
    isc_netaddr_t na_dummy;
    result = token_addr(pctx, flags, &na_dummy);
    return (ISC_TF(result == ISC_R_SUCCESS));
}

isc_result_t
cfg_parse_rawport(cfg_parser_t *pctx, unsigned int flags, in_port_t *port) {
    isc_result_t result;

    CHECK(cfg_gettoken(pctx, ISC_LEXOPT_NUMBER));

    if ((flags & CFG_ADDR_WILDOK) != 0 &&
        pctx->token.type == isc_tokentype_string &&
        strcmp(TOKEN_STRING(pctx), "*") == 0) {
        *port = 0;
        return (ISC_R_SUCCESS);
    }
    if (pctx->token.type != isc_tokentype_number) {
        cfg_parser_error(pctx, CFG_LOG_NEAR,
                 "expected port number or '*'");
        return (ISC_R_UNEXPECTEDTOKEN);
    }
    if (pctx->token.value.as_ulong >= 65536U) {
        cfg_parser_error(pctx, CFG_LOG_NEAR,
                 "port number out of range");
        return (ISC_R_UNEXPECTEDTOKEN);
    }
    *port = (in_port_t)(pctx->token.value.as_ulong);
    return (ISC_R_SUCCESS);
 cleanup:
    return (result);
}

void
cfg_print_rawaddr(cfg_printer_t *pctx, const isc_netaddr_t *na) {
    isc_result_t result;
    char text[128];
    isc_buffer_t buf;

    isc_buffer_init(&buf, text, sizeof(text));
    result = isc_netaddr_totext(na, &buf);
    RUNTIME_CHECK(result == ISC_R_SUCCESS);
    cfg_print_chars(pctx, isc_buffer_base(&buf), isc_buffer_usedlength(&buf));
}

/* netaddr */

static unsigned int netaddr_flags = CFG_ADDR_V4OK | CFG_ADDR_V6OK;
static unsigned int netaddr4_flags = CFG_ADDR_V4OK;
static unsigned int netaddr4wild_flags = CFG_ADDR_V4OK | CFG_ADDR_WILDOK;
static unsigned int netaddr6_flags = CFG_ADDR_V6OK;
static unsigned int netaddr6wild_flags = CFG_ADDR_V6OK | CFG_ADDR_WILDOK;

static isc_result_t
parse_netaddr(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    cfg_obj_t *obj = NULL;
    isc_netaddr_t netaddr;
    unsigned int flags = *(const unsigned int *)type->of;

    CHECK(cfg_create_obj(pctx, type, &obj));
    CHECK(cfg_parse_rawaddr(pctx, flags, &netaddr));
    isc_sockaddr_fromnetaddr(&obj->value.sockaddr, &netaddr, 0);
    *ret = obj;
    return (ISC_R_SUCCESS);
 cleanup:
    CLEANUP_OBJ(obj);
    return (result);
}

static void
cfg_doc_netaddr(cfg_printer_t *pctx, const cfg_type_t *type) {
    const unsigned int *flagp = type->of;
    int n = 0;
    if (*flagp != CFG_ADDR_V4OK && *flagp != CFG_ADDR_V6OK)
        cfg_print_chars(pctx, "( ", 2);
    if (*flagp & CFG_ADDR_V4OK) {
        cfg_print_cstr(pctx, "<ipv4_address>");
        n++;
    }
    if (*flagp & CFG_ADDR_V6OK) {
        if (n != 0)
            cfg_print_chars(pctx, " | ", 3);
        cfg_print_cstr(pctx, "<ipv6_address>");
        n++;
    }
    if (*flagp & CFG_ADDR_WILDOK) {
        if (n != 0)
            cfg_print_chars(pctx, " | ", 3);
        cfg_print_chars(pctx, "*", 1);
        n++;
    }
    if (*flagp != CFG_ADDR_V4OK && *flagp != CFG_ADDR_V6OK)
        cfg_print_chars(pctx, " )", 2);
}

cfg_type_t cfg_type_netaddr = {
    "netaddr", parse_netaddr, cfg_print_sockaddr, cfg_doc_netaddr,
    &cfg_rep_sockaddr, &netaddr_flags
};

cfg_type_t cfg_type_netaddr4 = {
    "netaddr4", parse_netaddr, cfg_print_sockaddr, cfg_doc_netaddr,
    &cfg_rep_sockaddr, &netaddr4_flags
};

cfg_type_t cfg_type_netaddr4wild = {
    "netaddr4wild", parse_netaddr, cfg_print_sockaddr, cfg_doc_netaddr,
    &cfg_rep_sockaddr, &netaddr4wild_flags
};

cfg_type_t cfg_type_netaddr6 = {
    "netaddr6", parse_netaddr, cfg_print_sockaddr, cfg_doc_netaddr,
    &cfg_rep_sockaddr, &netaddr6_flags
};

cfg_type_t cfg_type_netaddr6wild = {
    "netaddr6wild", parse_netaddr, cfg_print_sockaddr, cfg_doc_netaddr,
    &cfg_rep_sockaddr, &netaddr6wild_flags
};

/* netprefix */

isc_result_t
cfg_parse_netprefix(cfg_parser_t *pctx, const cfg_type_t *type,
            cfg_obj_t **ret)
{
    cfg_obj_t *obj = NULL;
    isc_result_t result;
    isc_netaddr_t netaddr;
    unsigned int addrlen, prefixlen;
    UNUSED(type);

    CHECK(cfg_parse_rawaddr(pctx, CFG_ADDR_V4OK | CFG_ADDR_V4PREFIXOK |
                CFG_ADDR_V6OK, &netaddr));
    switch (netaddr.family) {
    case AF_INET:
        addrlen = 32;
        break;
    case AF_INET6:
        addrlen = 128;
        break;
    default:
        addrlen = 0;
        INSIST(0);
        break;
    }
    CHECK(cfg_peektoken(pctx, 0));
    if (pctx->token.type == isc_tokentype_special &&
        pctx->token.value.as_char == '/') {
        CHECK(cfg_gettoken(pctx, 0)); /* read "/" */
        CHECK(cfg_gettoken(pctx, ISC_LEXOPT_NUMBER));
        if (pctx->token.type != isc_tokentype_number) {
            cfg_parser_error(pctx, CFG_LOG_NEAR,
                     "expected prefix length");
            return (ISC_R_UNEXPECTEDTOKEN);
        }
        prefixlen = pctx->token.value.as_ulong;
        if (prefixlen > addrlen) {
            cfg_parser_error(pctx, CFG_LOG_NOPREP,
                     "invalid prefix length");
            return (ISC_R_RANGE);
        }
    } else {
        prefixlen = addrlen;
    }
    CHECK(cfg_create_obj(pctx, &cfg_type_netprefix, &obj));
    obj->value.netprefix.address = netaddr;
    obj->value.netprefix.prefixlen = prefixlen;
    *ret = obj;
    return (ISC_R_SUCCESS);
 cleanup:
    cfg_parser_error(pctx, CFG_LOG_NEAR, "expected network prefix");
    return (result);
}

static void
print_netprefix(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    const cfg_netprefix_t *p = &obj->value.netprefix;

    cfg_print_rawaddr(pctx, &p->address);
    cfg_print_chars(pctx, "/", 1);
    cfg_print_rawuint(pctx, p->prefixlen);
}

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

void
cfg_obj_asnetprefix(const cfg_obj_t *obj, isc_netaddr_t *netaddr,
            unsigned int *prefixlen) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_netprefix);
    *netaddr = obj->value.netprefix.address;
    *prefixlen = obj->value.netprefix.prefixlen;
}

cfg_type_t cfg_type_netprefix = {
    "netprefix", cfg_parse_netprefix, print_netprefix, cfg_doc_terminal,
    &cfg_rep_netprefix, NULL
};

static isc_result_t
parse_sockaddrsub(cfg_parser_t *pctx, const cfg_type_t *type,
          int flags, cfg_obj_t **ret)
{
    isc_result_t result;
    isc_netaddr_t netaddr;
    in_port_t port = 0;
    cfg_obj_t *obj = NULL;

    CHECK(cfg_create_obj(pctx, type, &obj));
    CHECK(cfg_parse_rawaddr(pctx, flags, &netaddr));
    CHECK(cfg_peektoken(pctx, 0));
    if (pctx->token.type == isc_tokentype_string &&
        strcasecmp(TOKEN_STRING(pctx), "port") == 0) {
        CHECK(cfg_gettoken(pctx, 0)); /* read "port" */
        CHECK(cfg_parse_rawport(pctx, flags, &port));
    }
    isc_sockaddr_fromnetaddr(&obj->value.sockaddr, &netaddr, port);
    *ret = obj;
    return (ISC_R_SUCCESS);

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

static unsigned int sockaddr_flags = CFG_ADDR_V4OK | CFG_ADDR_V6OK;
cfg_type_t cfg_type_sockaddr = {
    "sockaddr", cfg_parse_sockaddr, cfg_print_sockaddr, cfg_doc_sockaddr,
    &cfg_rep_sockaddr, &sockaddr_flags
};

isc_result_t
cfg_parse_sockaddr(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    const unsigned int *flagp = type->of;
    return (parse_sockaddrsub(pctx, &cfg_type_sockaddr, *flagp, ret));
}

void
cfg_print_sockaddr(cfg_printer_t *pctx, const cfg_obj_t *obj) {
    isc_netaddr_t netaddr;
    in_port_t port;
    char buf[ISC_NETADDR_FORMATSIZE];

    isc_netaddr_fromsockaddr(&netaddr, &obj->value.sockaddr);
    isc_netaddr_format(&netaddr, buf, sizeof(buf));
    cfg_print_cstr(pctx, buf);
    port = isc_sockaddr_getport(&obj->value.sockaddr);
    if (port != 0) {
        cfg_print_chars(pctx, " port ", 6);
        cfg_print_rawuint(pctx, port);
    }
}

void
cfg_doc_sockaddr(cfg_printer_t *pctx, const cfg_type_t *type) {
    const unsigned int *flagp = type->of;
    int n = 0;
    cfg_print_chars(pctx, "( ", 2);
    if (*flagp & CFG_ADDR_V4OK) {
        cfg_print_cstr(pctx, "<ipv4_address>");
        n++;
    }
    if (*flagp & CFG_ADDR_V6OK) {
        if (n != 0)
            cfg_print_chars(pctx, " | ", 3);
        cfg_print_cstr(pctx, "<ipv6_address>");
        n++;
    }
    if (*flagp & CFG_ADDR_WILDOK) {
        if (n != 0)
            cfg_print_chars(pctx, " | ", 3);
        cfg_print_chars(pctx, "*", 1);
        n++;
    }
    cfg_print_chars(pctx, " ) ", 3);
    if (*flagp & CFG_ADDR_WILDOK) {
        cfg_print_cstr(pctx, "[ port ( <integer> | * ) ]");
    } else {
        cfg_print_cstr(pctx, "[ port <integer> ]");
    }
}

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

const isc_sockaddr_t *
cfg_obj_assockaddr(const cfg_obj_t *obj) {
    REQUIRE(obj != NULL && obj->type->rep == &cfg_rep_sockaddr);
    return (&obj->value.sockaddr);
}

isc_result_t
cfg_gettoken(cfg_parser_t *pctx, int options) {
    isc_result_t result;

    if (pctx->seen_eof)
        return (ISC_R_SUCCESS);

    options |= (ISC_LEXOPT_EOF | ISC_LEXOPT_NOMORE);

 redo:
    pctx->token.type = isc_tokentype_unknown;
    result = isc_lex_gettoken(pctx->lexer, options, &pctx->token);
    pctx->ungotten = ISC_FALSE;
    pctx->line = isc_lex_getsourceline(pctx->lexer);

    switch (result) {
    case ISC_R_SUCCESS:
        if (pctx->token.type == isc_tokentype_eof) {
            result = isc_lex_close(pctx->lexer);
            INSIST(result == ISC_R_NOMORE ||
                   result == ISC_R_SUCCESS);

            if (isc_lex_getsourcename(pctx->lexer) != NULL) {
                /*
                 * Closed an included file, not the main file.
                 */
                cfg_listelt_t *elt;
                elt = ISC_LIST_TAIL(pctx->open_files->
                            value.list);
                INSIST(elt != NULL);
                ISC_LIST_UNLINK(pctx->open_files->
                        value.list, elt, link);
                ISC_LIST_APPEND(pctx->closed_files->
                        value.list, elt, link);
                goto redo;
            }
            pctx->seen_eof = ISC_TRUE;
        }
        break;

    case ISC_R_NOSPACE:
        /* More understandable than "ran out of space". */
        cfg_parser_error(pctx, CFG_LOG_NEAR, "token too big");
        break;

    case ISC_R_IOERROR:
        cfg_parser_error(pctx, 0, "%s",
                 isc_result_totext(result));
        break;

    default:
        cfg_parser_error(pctx, CFG_LOG_NEAR, "%s",
                 isc_result_totext(result));
        break;
    }
    return (result);
}

void
cfg_ungettoken(cfg_parser_t *pctx) {
    if (pctx->seen_eof)
        return;
    isc_lex_ungettoken(pctx->lexer, &pctx->token);
    pctx->ungotten = ISC_TRUE;
}

isc_result_t
cfg_peektoken(cfg_parser_t *pctx, int options) {
    isc_result_t result;
    CHECK(cfg_gettoken(pctx, options));
    cfg_ungettoken(pctx);
 cleanup:
    return (result);
}

/*
 * Get a string token, accepting both the quoted and the unquoted form.
 * Log an error if the next token is not a string.
 */
static isc_result_t
cfg_getstringtoken(cfg_parser_t *pctx) {
    isc_result_t result;

    result = cfg_gettoken(pctx, CFG_LEXOPT_QSTRING);
    if (result != ISC_R_SUCCESS)
        return (result);

    if (pctx->token.type != isc_tokentype_string &&
        pctx->token.type != isc_tokentype_qstring) {
        cfg_parser_error(pctx, CFG_LOG_NEAR, "expected string");
        return (ISC_R_UNEXPECTEDTOKEN);
    }
    return (ISC_R_SUCCESS);
}

void
cfg_parser_error(cfg_parser_t *pctx, unsigned int flags, const char *fmt, ...) {
    va_list args;
    va_start(args, fmt);
    parser_complain(pctx, ISC_FALSE, flags, fmt, args);
    va_end(args);
    pctx->errors++;
}

void
cfg_parser_warning(cfg_parser_t *pctx, unsigned int flags, const char *fmt, ...) {
    va_list args;
    va_start(args, fmt);
    parser_complain(pctx, ISC_TRUE, flags, fmt, args);
    va_end(args);
    pctx->warnings++;
}

#define MAX_LOG_TOKEN 30 /* How much of a token to quote in log messages. */

static char *
current_file(cfg_parser_t *pctx) {
    static char none[] = "none";
    cfg_listelt_t *elt;
    cfg_obj_t *fileobj;

    if (pctx->open_files == NULL)
        return (none);
    elt = ISC_LIST_TAIL(pctx->open_files->value.list);
    if (elt == NULL)
          return (none);

    fileobj = elt->obj;
    INSIST(fileobj->type == &cfg_type_qstring);
    return (fileobj->value.string.base);
}

static void
parser_complain(cfg_parser_t *pctx, isc_boolean_t is_warning,
        unsigned int flags, const char *format,
        va_list args)
{
    char tokenbuf[MAX_LOG_TOKEN + 10];
    static char where[ISC_DIR_PATHMAX + 100];
    static char message[2048];
    int level = ISC_LOG_ERROR;
    const char *prep = "";
    size_t len;

    if (is_warning)
        level = ISC_LOG_WARNING;

    snprintf(where, sizeof(where), "%s:%u: ",
         current_file(pctx), pctx->line);

    len = vsnprintf(message, sizeof(message), format, args);
    if (len >= sizeof(message))
        FATAL_ERROR(__FILE__, __LINE__,
                "error message would overflow");

    if ((flags & (CFG_LOG_NEAR|CFG_LOG_BEFORE|CFG_LOG_NOPREP)) != 0) {
        isc_region_t r;

        if (pctx->ungotten)
            (void)cfg_gettoken(pctx, 0);

        if (pctx->token.type == isc_tokentype_eof) {
            snprintf(tokenbuf, sizeof(tokenbuf), "end of file");
        } else if (pctx->token.type == isc_tokentype_unknown) {
            flags = 0;
            tokenbuf[0] = '\0';
        } else {
            isc_lex_getlasttokentext(pctx->lexer,
                         &pctx->token, &r);
            if (r.length > MAX_LOG_TOKEN)
                snprintf(tokenbuf, sizeof(tokenbuf),
                     "'%.*s...'", MAX_LOG_TOKEN, r.base);
            else
                snprintf(tokenbuf, sizeof(tokenbuf),
                     "'%.*s'", (int)r.length, r.base);
        }

        /* Choose a preposition. */
        if (flags & CFG_LOG_NEAR)
            prep = " near ";
        else if (flags & CFG_LOG_BEFORE)
            prep = " before ";
        else
            prep = " ";
    } else {
        tokenbuf[0] = '\0';
    }
    isc_log_write(pctx->lctx, CAT, MOD, level,
              "%s%s%s%s", where, message, prep, tokenbuf);
}

void
cfg_obj_log(const cfg_obj_t *obj, isc_log_t *lctx, int level,
        const char *fmt, ...) {
    va_list ap;
    char msgbuf[2048];

    if (! isc_log_wouldlog(lctx, level))
        return;

    va_start(ap, fmt);

    vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap);
    isc_log_write(lctx, CAT, MOD, level,
              "%s:%u: %s",
              obj->file == NULL ? "<unknown file>" : obj->file,
              obj->line, msgbuf);
    va_end(ap);
}

const char *
cfg_obj_file(const cfg_obj_t *obj) {
    return (obj->file);
}

unsigned int
cfg_obj_line(const cfg_obj_t *obj) {
    return (obj->line);
}

isc_result_t
cfg_create_obj(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    cfg_obj_t *obj;

    obj = isc_mem_get(pctx->mctx, sizeof(cfg_obj_t));
    if (obj == NULL)
        return (ISC_R_NOMEMORY);
    obj->type = type;
    obj->file = current_file(pctx);
    obj->line = pctx->line;
    *ret = obj;
    return (ISC_R_SUCCESS);
}

static void
map_symtabitem_destroy(char *key, unsigned int type,
               isc_symvalue_t symval, void *userarg)
{
    cfg_obj_t *obj = symval.as_pointer;
    cfg_parser_t *pctx = (cfg_parser_t *)userarg;

    UNUSED(key);
    UNUSED(type);

    cfg_obj_destroy(pctx, &obj);
}


static isc_result_t
create_map(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
    isc_result_t result;
    isc_symtab_t *symtab = NULL;
    cfg_obj_t *obj = NULL;

    CHECK(cfg_create_obj(pctx, type, &obj));
    CHECK(isc_symtab_create(pctx->mctx, 5, /* XXX */
                map_symtabitem_destroy,
                pctx, ISC_FALSE, &symtab));
    obj->value.map.symtab = symtab;
    obj->value.map.id = NULL;

    *ret = obj;
    return (ISC_R_SUCCESS);

 cleanup:
    if (obj != NULL)
        isc_mem_put(pctx->mctx, obj, sizeof(*obj));
    return (result);
}

static void
free_map(cfg_parser_t *pctx, cfg_obj_t *obj) {
    CLEANUP_OBJ(obj->value.map.id);
    isc_symtab_destroy(&obj->value.map.symtab);
}

isc_boolean_t
cfg_obj_istype(const cfg_obj_t *obj, const cfg_type_t *type) {
    return (ISC_TF(obj->type == type));
}

/*
 * Destroy 'obj', a configuration object created in 'pctx'.
 */
void
cfg_obj_destroy(cfg_parser_t *pctx, cfg_obj_t **objp) {
    cfg_obj_t *obj = *objp;
    obj->type->rep->free(pctx, obj);
    isc_mem_put(pctx->mctx, obj, sizeof(cfg_obj_t));
    *objp = NULL;
}

static void
free_noop(cfg_parser_t *pctx, cfg_obj_t *obj) {
    UNUSED(pctx);
    UNUSED(obj);
}

void
cfg_doc_obj(cfg_printer_t *pctx, const cfg_type_t *type) {
    type->doc(pctx, type);
}

void
cfg_doc_terminal(cfg_printer_t *pctx, const cfg_type_t *type) {
    cfg_print_chars(pctx, "<", 1);
    cfg_print_cstr(pctx, type->name);
    cfg_print_chars(pctx, ">", 1);
}

void
cfg_print_grammar(const cfg_type_t *type,
    void (*f)(void *closure, const char *text, int textlen),
    void *closure)
{
    cfg_printer_t pctx;
    pctx.f = f;
    pctx.closure = closure;
    pctx.indent = 0;
    cfg_doc_obj(&pctx, type);
}