/*-
 * Copyright (c) 2003-2005 MAEKAWA Masahide <maekawa@cvsync.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 author 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 AUTHOR 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 AUTHOR 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.
 */

#include <sys/types.h>

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

#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <string.h>

#include "compat_stdbool.h"

#include "logmsg.h"
#include "token.h"

size_t lineno = 1;

const struct token_keyword *
token_get_keyword(FILE *fp, const struct token_keyword *keys)
{
	const struct token_keyword *key;
	struct token tk;
	int c;

	if (!token_skip_whitespace(fp)) {
		logmsg_err("premature EOF");
		return (false);
	}

	tk.length = 0;

	if ((c = fgetc(fp)) == EOF) {
		logmsg_err("premature EOF");
		return (NULL);
	}

	while (isalnum(c) || (c == '{') || (c == '}') || (c == '-')) {
		tk.token[tk.length++] = c;
		if (tk.length == sizeof(tk.token)) {
			logmsg_err("too long token");
			return (NULL);
		}
		if ((c = fgetc(fp)) == EOF) {
			logmsg_err("premature EOF");
			return (NULL);
		}
	}
	if (tk.length == 0) {
		logmsg_err("line %u: no keywords", lineno);
		return (NULL);
	}
	tk.token[tk.length] = '\0';

	if (ungetc(c, fp) == EOF)
		return (false);

	for (key = keys ; key->name != NULL ; key++) {
		if ((tk.length == key->namelen) &&
		    (memcmp(tk.token, key->name, tk.length) == 0)) {
			return (key);
		}
	}

	logmsg_err("%s: invalid keyword", tk.token);

	return (NULL);
}

bool
token_get_number(FILE *fp, unsigned long *num)
{
	struct token tk;
	char *ep;
	unsigned long v;

	if (!token_get_string(fp, &tk))
		return (false);

	errno = 0;
	v = strtoul(tk.token, &ep, 0);
	if ((ep == NULL) || (*ep != '\0') || ((v == 0) && (errno == EINVAL)) ||
	    ((v == ULONG_MAX) && (errno == ERANGE))) {
		logmsg_err("line %u: %s: %s", lineno, tk.token,
			   strerror(EINVAL));
		return (false);
	}

	*num = v;

	return (true);
}

bool
token_get_string(FILE *fp, struct token *tk)
{
	char *quot;
	int c;

	tk->length = 0;

	if (!token_skip_whitespace(fp)) {
		logmsg_err("premature EOF");
		return (false);
	}

	if ((c = fgetc(fp)) == EOF) {
		logmsg_err("premature EOF");
		return (false);
	}

	if ((quot = strchr("\"'", c)) == NULL) {
		do {
			tk->token[tk->length++] = c;
			if (tk->length == sizeof(tk->token)) {
				logmsg_err("too long token");
				return (false);
			}
			if ((c = fgetc(fp)) == EOF) {
				logmsg_err("premature EOF");
				return (false);
			}
		} while (!isspace(c));
		if (c == '\n')
			lineno++;
	} else {
		if ((c = fgetc(fp)) == EOF) {
			logmsg_err("premature EOF");
			return (false);
		}
		while (c != *quot) {
			tk->token[tk->length++] = c;
			if (tk->length == sizeof(tk->token)) {
				logmsg_err("too long token");
				return (false);
			}
			if ((c = fgetc(fp)) == EOF) {
				logmsg_err("premature EOF");
				return (false);
			}
			if (c == '\n')  {
				logmsg_err("missing close quotation %c",
					   *quot);
				return (false);
			}
		}
		if (tk->length == 0) {
			logmsg_err("empty string");
			return (false);
		}
	}

	tk->token[tk->length] = '\0';

	return (true);
}

bool
token_skip_whitespace(FILE *fp)
{
	int c;

	for (;;) {
		do {
			if ((c = fgetc(fp)) == EOF)
				return (false);
			if (c == '\n')
				lineno++;
		} while (isspace(c));

		if (c != '#')
			break;

		do {
			if ((c = fgetc(fp)) == EOF)
				return (false);
		} while (c != '\n');
		lineno++;
	}

	if (ungetc(c, fp) == EOF)
		return (false);

	return (true);
}