tftp-hpa/trq/trq.c

/*
 * trq.c
 *
 *  Created on: 17 авг. 2022 г.
 *      Author: Alexander Zhirov
 *      Mail: alexander@zhirov.website
 *      Telegram: alexanderzhirov
 */

#include "trq.h"

#include <syslog.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <regex.h>

void ts_free(ts_args *args)
{
    if (args)
    {
        if (args->command)
            free(args->command);
        if (args->file_src)
            free(args->file_src);
        if (args->file_dst)
            free(args->file_dst);
        if (args->path_src)
            free(args->path_src);
        if (args->command)
            free(args->path_dst);
        free(args);
    }
}

static char* ts_concat_path(const char *file)
{
    if (!file)
    {
        syslog(LOG_NOTICE, "TRQ Invalid value file (ts_concat_path)\n");
        exit(3);
    }
    const char *path_mac = "mac.cfg/";
    size_t len1 = strlen(path_mac);
    size_t len2 = strlen(file);
    char *result = (char*) malloc(sizeof(char) * (len1 + len2 + 1));
    if (!result)
    {
        syslog(LOG_NOTICE, "TRQ Disk full or allocation exceeded (ts_concat_path)\n");
        exit(3);
    }
    strncpy(result, path_mac, (len1 + 1));
    strncpy(result + len1, file, (len2 + 1));
    return result;
}

static char* ts_copy_string(const char *string)
{
    if (!string)
        return NULL;
    int len = strlen(string);
    char *tmp = (char*) calloc(1, sizeof(char) * (len + 1));
    if (!tmp)
    {
        syslog(LOG_NOTICE, "TRQ Disk full or allocation exceeded (ts_copy_string)\n");
        exit(3);
    }
    strncpy(tmp, string, (len + 1));
    return tmp;
}

ts_args* ts_get_arguments(const char *filename, const char *path)
{
    ts_args *args = (ts_args*) calloc(1, sizeof(ts_args));
    if (!args)
    {
        syslog(LOG_NOTICE, "TRQ Disk full or allocation exceeded (ts_get_arguments)\n");
        exit(3);
    }
    char separator[2] = ";\0";
    char *part = NULL;
    int len = strlen(filename);
    int next = 1; /* reading the next iteration */
    char *tmp_filename = (char*) calloc(1, sizeof(char) * (len + 1));
    if (!tmp_filename)
    {
        syslog(LOG_NOTICE, "TRQ Disk full or allocation exceeded (ts_get_arguments)\n");
        exit(3);
    }
    strncpy(tmp_filename, filename, (len + 1));
    part = strtok(tmp_filename, separator);
    while (part)
    {
        switch (args->size)
        {
        case 0:
            regex_t regex;
            regcomp(&regex, "^01-[0-9a-f]{2}(-[0-9a-f]{2}){5}$", REG_EXTENDED);
            int reti = regexec(&regex, part, 0, NULL, 0);
            if (reti)
            {
                syslog(LOG_NOTICE, "TRQ The MAC address was entered incorrectly (ts_get_arguments)\n");
                exit(100);
            }
            args->file_dst = ts_copy_string(part);
            args->path_dst = ts_concat_path(part);
            break;
        case 1:
            if (!strncmp("cr", part, 3)) {}
            else if (!strncmp("rm", part, 3))
                next = 0;
            else
            {
                syslog(LOG_NOTICE, "TRQ The command was specified incorrectly (ts_get_arguments)\n");
                exit(100);
            }
            args->command = ts_copy_string(part);
            break;
        case 2:
            args->file_src = ts_copy_string(part);
            args->path_src = ts_concat_path(part);
            break;
        default:
            syslog(LOG_NOTICE, "TRQ Invalid request format (ts_get_arguments)\n");
            exit(100);
        }
        ++args->size;
        if (next)
            part = strtok(NULL, separator);
        else
            part = NULL;
    }
    free(tmp_filename);
    if (!args->size)
    {
        free(args);
        args = NULL;
    }
    return args;
}

void ts_syslog(const ts_args *args)
{
    if (args)
    {
        if (args->size > 2)
            syslog(LOG_NOTICE, "TRQ Create symlink %s on %s\n", args->file_dst, args->file_src);
        else
            syslog(LOG_NOTICE, "TRQ Remove symlink %s\n", args->file_dst);
    }
}

void ts_symlink(const ts_args *args)
{
    if (args)
    {
        if (args->size > 2)
        {
            if (access(args->path_src, F_OK) == 0 && !symlink(args->file_src, args->path_dst))
                syslog(LOG_NOTICE, "TRQ A symbolic link %s has been created\n", args->file_dst);
            else
                syslog(LOG_NOTICE, "TRQ Failed to create symbolic link %s. %s\n", args->file_dst, strerror(errno));
        }
        else
        {
            if (access(args->path_dst, F_OK) == 0 && !unlink(args->path_dst))
                syslog(LOG_NOTICE, "TRQ A symbolic link %s has been removed\n", args->file_dst);
            else
                syslog(LOG_NOTICE, "TRQ Failed to remove symbolic link %s. %s\n", args->file_dst, strerror(errno));
        }
    }
}