/**
 * Script to be executed as root via cron to rotate user-session 
 * logs which are generated by ttyrec in a defined cycle.
 * 
 */

#define RETENTION_IN_DAYS 7
#define USER_SESSION_DIR "/etc"

#include "stdio.h"
#include "dirent.h"
#include "sys/stat.h"
#include "unistd.h"
#include "fcntl.h"
#include "sys/param.h"
#include "stdlib.h"
#include "time.h"

void rotate_session_dir();

int main()
{
    printf("Retention set to %d days for user session folder %s\n",
            RETENTION_IN_DAYS, USER_SESSION_DIR);

    rotate_session_dir();
    return 0;
}

void rotate_session_dir()
{
    int secs_in_week = 60 * 60 * 24 * RETENTION_IN_DAYS;
    struct dirent *entry;
    struct stat file_status;
    DIR *dir = opendir(USER_SESSION_DIR);
    time_t system_time;
    time_t time_diff;

    system_time = time(NULL);
    //printf("System time is %d", system_time);


    if (!dir) {
        perror("Could not open defined User Session directory");
        exit(1);
    }
    chdir(USER_SESSION_DIR);
    while ((entry = readdir(dir)) != NULL) {
        if ((strcmp(entry->d_name, ".") == 0) || (strcmp(entry->d_name, "..") == 0))
            continue;

        if (stat(entry->d_name, &file_status) == 0) {
            if (!S_ISDIR(file_status.st_mode)) {
                /**
                 * Remove all files from folder which are older
                 * than 7 days -- append-only flag will need
                 * to be removed from each file before the remove
                 * operation.
                 *
                 * Note: need to remote append only attr here as well 
                 * on the file... how!?
                 */
                time_diff = difftime(time(NULL), file_status.st_atime);

                if (secs_in_week > time_diff) {
                    printf("We need to delete the file: %s\n", 
                            entry->d_name);
                }

            }
        }
    }

    if (closedir(dir) == -1) {
        perror("closedir failure");
        exit(1);
    }
}