/* check_dircount.c

check number of entries in a directory
for monitoring spool directories

by Doke Scott, doke at udel.edu, 12 Sep 2003 
*/


#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>



int verbose = 0;
char *program_name;
char *crit_range = "20000";
char *warn_range = "10000";



void
usage( int rc ) {
    fprintf( stderr, "Usage: %s [-v] [-c range] [-w range] <directory>\n"
	"    -v        verbose\n" 
	"    -c range  critical if outside range, default 20000\n"
	"    -w range  critical if outside range, default 10000\n"
	"    range is 200:1000, :1000, 200:, 1000, inclusive\n",
	program_name );
    exit( rc );
    }





int 
in_range( int count, char *range ) { 
    int l = 0, h = 0;

    if ( strchr( range, ':' ) ) { 
	if ( sscanf( range, "%u:%u", &l, &h ) == 2 ) { 
	    //printf( "count %d, l %d, h %d\n", count, l, h );
	    if ( count < l || h < count )
		return 0;
	    return 1;
	    }
	else if ( sscanf( range, ":%u", &h ) == 1 ) { 
	    //printf( "count %d, l %d, h %d\n", count, l, h );
	    if ( h < count )
		return 0;
	    return 1;
	    }
	else if ( sscanf( range, "%u:", &l ) == 1 ) { 
	    //printf( "count %d, l %d, h %d\n", count, l, h );
	    if ( count < l )
		return 0;
	    return 1;
	    }
	}
    else if ( sscanf( range, "%u", &h ) == 1 ) { 
	//printf( "count %d, l %d, h %d\n", count, l, h );
	if ( h < count )
	    return 0;
	return 1;
	}

    fprintf( stderr, "cannot parse range '%s'\n", range );
    usage( -1 );
    }









int 
main( int argc, char **argv )  {
    char *dirname;
    DIR *dirp;
    int c, count, rc;

    program_name = argv[0];

    while ( ( c = getopt( argc, argv, "vc:w:" ) ) >= 0 ) {
	switch ( c ) {
	    case 'v':
		verbose++;
		break;
	    case 'c':
		crit_range = optarg;
		break;
	    case 'w': 
		warn_range = optarg;
		break;
	    default:
		usage( -1 );
		break;
	    }
	}

    if ( optind >= argc || ! argv[ optind ] ) 
	usage( -1 );
    dirname = argv[ optind ];
 
    dirp = opendir( dirname ); 
    if ( ! dirp ) { 
	fprintf( stderr, "can't open directory %s: %s\n", 
	    dirname, strerror( errno ) );
	exit( -1 );
	}
    count = 0;
    while ( readdir( dirp ) ) { 
	count++;
	}
    closedir( dirp );
    count -= 2;  // . and ..

    if ( ! in_range( count, crit_range ) ) { 
	printf( "CRITICAL" );
	rc = 2;
	}
    else if ( ! in_range( count, warn_range ) ) { 
	printf( "Warning" );
	rc = 1;
	}
    else { 
	printf( "OK" );
	rc = 0;
	}
    printf( ": %d files in %s\n", count, dirname );
    return rc;
    }