Geografic-Information-System/lib/vector/dglib/examples/delnode.c

/* LIBDGL -- a Directed Graph Library implementation
 * Copyright (C) 2002 Roberto Micarelli
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * Source best viewed with tabstop=4
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <time.h>
#include <errno.h>
#include <math.h>

#include "../type.h"
#include "../graph.h"

#include "opt.h"

int main(int argc, char **argv)
{
    dglGraph_s graph;
    dglInt32_t nNode;
    int nret, fd;

    /* program options
     */
    char *pszGraph;
    char *pszGraphOut;
    char *pszNode;

    GNO_BEGIN			/* short   long                default     variable        help */
	GNO_OPTION("g", "graph", NULL, &pszGraph, "Input Graph file")
	GNO_OPTION("o", "graphout", NULL, &pszGraphOut, "Output Graph file")
	GNO_OPTION("n", "node", NULL, &pszNode, "Node Id to cancel")
	GNO_END if (GNO_PARSE(argc, argv) < 0) {
	return 1;
    }
    /*
     * options parsed
     */

    if (pszNode == NULL) {
	GNO_HELP("delnode usage");
	return 1;
    }
    nNode = atol(pszNode);

    printf("Graph read:\n");
    if ((fd = open(pszGraph, O_RDONLY)) < 0) {
	perror("open");
	return 1;
    }
    nret = dglRead(&graph, fd);
    if (nret < 0) {
	fprintf(stderr, "dglRead error: %s\n", dglStrerror(&graph));
	return 1;
    }
    close(fd);
    printf("Done.\n");

    printf("Graph unflatten:\n");
    nret = dglUnflatten(&graph);
    if (nret < 0) {
	fprintf(stderr, "dglUnflatten error: %s\n", dglStrerror(&graph));
	return 1;
    }
    printf("Done.\n");

    nret = dglDelNode(&graph, nNode);
    if (nret < 0) {
	fprintf(stderr, "dglDelNode error: %s\n", dglStrerror(&graph));
	return 1;
    }

    printf("Graph flatten:\n");
    nret = dglFlatten(&graph);
    printf("Done.\n");

    if (pszGraphOut) {
	printf("Graph write: %s\n", pszGraphOut);
	if ((fd = open(pszGraphOut, O_WRONLY | O_CREAT | O_TRUNC, 0666)) < 0) {
	    perror("open");
	    return 1;
	}
	nret = dglWrite(&graph, fd);
	if (nret < 0) {
	    fprintf(stderr, "dglWrite error: %s\n", dglStrerror(&graph));
	    return 1;
	}
	close(fd);
	printf("Done.\n");
    }

    dglRelease(&graph);
    return 0;
}