config_api.c

这个开发机器人项目源码

/*
 * $Id: config_api.c,v 1.2 2003/09/13 20:18:22 dwalters Exp $
 * 
 * Copyright (C) 2001, 2002, 2003 Flavio de Ayra Mendes <[e-mail]>
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
 
#include <stdio.h>
#include <stdlib.h>
#define __USE_XOPEN
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "config_api.h"

/* for using with pthread_create() */
static void on_change(config_t *conf)
{
	struct stat st;
	time_t t = time(NULL);
	
	while (1) {
		/* timeout */
		sleep(conf->timeout);
		

		/* check if file is changed */
		if (fstat(conf->fd, &st) == -1)
			return;
		if (st.st_ctime > t) {
			/* if is changed execute func() and update t */
			t = st.st_ctime;
			conf->func(conf->func_arg);
		}
	}
}

int config_open(config_t *conf, const char *filename, int flag)
{
	struct stat st;
	char mode[2];
	
	/* set fopen() mode or return if flag is not valid */
	if (flag == C_WRITE) {
		if (stat(filename, &st) == -1)
			strcpy(mode, "w");
		else
			strcpy(mode, "r+");
	} else if (flag == C_READ) {
		strcpy(mode, "r");
	} else {
		return 0;
	}

	/* open itself */
	memset(conf, 0, sizeof(config_t));
	if (!(conf->fp = fopen(filename, mode))) {
		if (conf->debug)
			fprintf(stderr, "config_open(): cannot fopen() %s: %s",
					filename, strerror(errno));
		return 0;
	}	

	/* alloc and copy the config filename to the config_t */
	conf->filename = malloc(strlen(filename) + 1);
	if (conf->filename == NULL) {
		if (conf->debug)
			fprintf(stderr, "config_open(): cannot alocate space "
				"for filename: %s\n", strerror(errno));
		return 0;
	}
	strcpy(conf->filename, filename);
	/* set it as openned */
	conf->openned = 1;
	
	return 1;
}

int config_check(config_t *conf, int output)
{
	off_t initial_offset; /* offset saving */
	unsigned int line = 0; /* line number */
	unsigned int section = 0; 
	unsigned int error = 0; /* error checking */
	char buff[MAX_LINE_SIZE]; /* line buffer */
	char section_tmp[MAX_SECTION_SIZE]; /* tmporary for sscanf() */
	char option_tmp[MAX_OPTION_SIZE]; /* tmporary for sscanf() */
	char value_tmp[MAX_VALUE_SIZE]; /* tmporary for sscanf() */

	/* file not openned */
	if (!conf->openned) {
		if (conf->debug)
			fprintf(stderr, "config_check(): config file not "
					"openned\n");
		return 0;
	}

	/* save offset before change */
	initial_offset = ftell(conf->fp);
	
	/* let's work */
	while (!feof(conf->fp)) {
		/* get buffer */
		memset(buff, 0, MAX_LINE_SIZE);
		my_fgets(buff, MAX_LINE_SIZE, conf->fp);
		/* line counting */
		line++;

		/* ignore comments and blank lines */
		if (*buff == '#' || *buff == '\r' || *buff == '\n' || 
		    !strlen(buff))
			continue;
		
		/* cutt off every \n and \r of the string */
		chomp(buff);
		
		memset(section_tmp, 0, MAX_SECTION_SIZE);
		memset(option_tmp, 0, MAX_OPTION_SIZE);
		memset(value_tmp, 0, MAX_VALUE_SIZE);

		if (is_a_section(buff, section_tmp, MAX_SECTION_SIZE - 1)) {
			/* ok, its a section */
			section = 1;	
		} else if (is_an_option(buff, option_tmp, MAX_OPTION_SIZE - 1,
					value_tmp, MAX_VALUE_SIZE - 1)) {
			if (!section) {
				/* option without a section */
				error = 1;
				if (output)
					fprintf(stderr, "%s:%d: option '%s' "
							"whithout a section.\n",
							conf->filename, line, 
							option_tmp);
			}
		} else {
			error = 1;
			if (output)
				fprintf(stderr, "%s:%d: syntax error: '%s'\n", 
						conf->filename, line, buff);
		}
	}

	/* get back to initial offset */
	fseek(conf->fp, initial_offset, SEEK_SET);

	/* return 0 if failed or 1 if ok */
	return (error ? 0: 1);
}


int config_read(config_t *conf, const char *section, const char *option,
			char *dest, size_t dest_size)
{
	off_t option_offset;
	off_t section_offset;
	off_t initial_offset;
	char line_tmp[MAX_LINE_SIZE];
	
	/* return if the file isn't openned */
	if (!conf->openned) {
		if (conf->debug)
			fprintf(stderr, "config_read(): config file not "
					"openned\n");
		return 0;
	}

	/* save initial offset */
	initial_offset = ftell(conf->fp);

	/* return if section not found */
	if ((section_offset = find_section(conf->fp, section)) == -1) {
		if (conf->debug)
			fprintf(stderr, "config_read(): cannot find section "
					"'%s'\n", section);
		return 0;
	}

	/* return if option not found */
	if ((option_offset = find_option(conf->fp, option, 
					 section_offset)) == -1) {
		if (conf->debug)
			fprintf(stderr, "config_read(): cannot find option '%s'"
					" in section '%s'\n", option, section);
		return 0;
	}
	
	/* go to the option offset */
	fseek(conf->fp, option_offset, SEEK_SET);
	
	/* get the buffer and fix spaces */
	memset(line_tmp, 0, MAX_LINE_SIZE);
	my_fgets(line_tmp, MAX_LINE_SIZE, conf->fp);
	spacefix(line_tmp);


	/* return if something nasty happens with sscanf */
	if (!is_an_option(line_tmp, NULL, 0, dest ? dest : NULL, 
			  dest ? dest_size : 0)) {
		fprintf(stderr, "config_read(): cannot get value for option "
				"'%s'\n", option);
		return 0;
	}
	
	/* get back to initia offset */
	fseek(conf->fp, initial_offset, SEEK_SET);

	return 1;
}

int config_read_num(config_t *conf, const char *section, 
		    unsigned int option_num, char *dest, size_t dest_size)
{
	off_t section_offset;
	off_t initial_offset;
	char line_tmp[MAX_LINE_SIZE];
	
	/* return if the file isn't openned */
	if (!conf->openned) {
		if (conf->debug)
			fprintf(stderr, "config_read(): config file not "
					"openned\n");
		return 0;
	}
	
	if (dest == NULL || !dest_size) {
		if (conf->debug)
			fprintf(stderr, 
				"config_read(): invalid dest buffer\n");
		return 0;
	}

	if (!option_num) {
		if (conf->debug)
			fprintf(stderr, "config_read(): option_num is zero\n");
		
		return 0;
	}

	/* save initial offset */
	initial_offset = ftell(conf->fp);

	/* return if section not found */
	if ((section_offset = find_section(conf->fp, section)) == -1) {
		if (conf->debug)
			fprintf(stderr, "config_read(): cannot find section "
					"'%s'\n", section);
		return 0;
	}

	/* go to the option offset */
	fseek(conf->fp, section_offset, SEEK_SET);

	/* ignore the section line */
	my_fgets(line_tmp, MAX_LINE_SIZE, conf->fp);
	
	/* main loop to find the option */
	while (option_num--) {
		/* get the buffer and fix spaces */
		memset(line_tmp, 0, MAX_LINE_SIZE);
		my_fgets(line_tmp, MAX_LINE_SIZE, conf->fp);
		spacefix(line_tmp);
		
//		fprintf(stderr, "linha: %s\n", line_tmp);
		if (is_a_section(line_tmp, NULL, 0))
			return 0;

		/* return if something nasty happens with sscanf */
		if (!is_an_option(line_tmp, NULL, 0, 
				  (!option_num ? dest : NULL),
				  (!option_num ? dest_size : 0))) {
			option_num++;
		}
	}

	/* get back to initia offset */
	fseek(conf->fp, initial_offset, SEEK_SET);
	
	return 1;
}


int config_write(config_t *conf, const char *section, const char *option, 
		 const char *value)
{
	off_t section_offset; 
	off_t option_offset;
	off_t *write_offset;
	off_t initial_offset;
	char tmp[MAX_LINE_SIZE];
	FILE *tmp_fp;
	char template[] = "config_writeXXXXXX";

	/* return if the file isn't openned yet */
	if (!conf->openned) {
		if (conf->debug)
			fprintf(stderr, "config_write(): config file not "
					"openned\n");
		return 0;
	}

	/* save the initial offset */
	initial_offset = ftell(conf->fp);

	/* do nothing if is the same value */
	memset(tmp, 0, MAX_LINE_SIZE); 
	if (config_read(conf, section, option, tmp, MAX_LINE_SIZE))
		if (!strcmp(tmp, value))
			return 1;

	if ((section_offset = find_section(conf->fp, section)) == -1) {
		/* write at the end if section not found */
        	fseek(conf->fp, 0, SEEK_END);
        	fprintf(conf->fp, "\n[%s]\n", section);
        	fprintf(conf->fp, "%s = %s\n", option, value);
	} else {
		if ((option_offset = find_option(conf->fp, option, 
						  section_offset)) == -1) {
			fseek(conf->fp, section_offset, SEEK_SET);
			my_fgets(tmp, MAX_LINE_SIZE, conf->fp);
			section_offset = ftell(conf->fp);
			write_offset = &section_offset;
		} else { 
			/* option exisits. just change */
			write_offset = &option_offset;
		}
		
		/* start a tmporary file */
		tmp_fp = my_tmpfile(template, "/tmp");
		if (tmp_fp == NULL) {
			if (conf->debug)
				fprintf(stderr, "config_write(): cannot open "
						"temporary file\n");
			return 0;
		}

		/* copy everything after truncate point to tmp file */
		fseek(conf->fp, *write_offset, SEEK_SET);
		while (!feof(conf->fp)) {
			memset(tmp, 0, MAX_LINE_SIZE);
			my_fgets(tmp, MAX_LINE_SIZE, conf->fp);	
			fprintf(tmp_fp, "%s", tmp);
		}

		ftruncate(fileno(conf->fp), *write_offset);
		fseek(conf->fp, *write_offset, SEEK_SET);
        	fprintf(conf->fp, "%s = %s\n", option, value);
		
		rewind(tmp_fp);
		while (!feof(tmp_fp)) {
			memset(tmp, 0, MAX_LINE_SIZE);
			my_fgets(tmp, MAX_LINE_SIZE, tmp_fp);