write_lastwallpaper.c

/*
 * Copyright (c) 2004 - 2016 Han Boetes <hboetes@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "fbsetbg.h"


/*
 * Store arguments of the last remembered session for reuse for fbsetbg -l
 */
int
write_lastwallpaper(char *option, char *wallpaper)
{

        char           *lstwllpprarray[MAXLLW];
        FILE           *fp;
        char           *display, *tempstring;
        int             i = 0, j, ret, found = FALSE;

        if ((display = getenv("DISPLAY")) == NULL)
                errx (1, "the DISPLAY environment variable isn't set");

        tempstring = malloc(MAXPATHLEN);
        if (tempstring == NULL)
                err(1, "out of memory");

        /* First read ~/.lastwallpaper into an array */
        if ((fp = fopen(lastwallpaper, "r")) != NULL)
        {
                for (i = 0; i < MAXLLW; i++)
                {
                        lstwllpprarray[i] = malloc(MAXPATHLEN);
                        if (lstwllpprarray[i] == NULL)
                                err(1, "out of memory");


                        if (fgets(lstwllpprarray[i], MAXPATHLEN, fp) == NULL)
                                break;
                }

                /* Add sanity */
                if (fclose(fp) != 0)
                        err(1, "error");
        } else {
                /* Initiate  variable */
                lstwllpprarray[0] = malloc(MAXPATHLEN);
                if (lstwllpprarray[0] == NULL)
                        err(1, "out of memory");

                lstwllpprarray[0][0] = '\0';
        }

        /* And then  write all lines back again. */
        if ((fp = fopen(lastwallpaper, "w")) == NULL)
                err(1, "%s", lastwallpaper);

        for (j = 0; j <= i; j++)
        {
                if (lstwllpprarray[j][0] != '\0' && lstwllpprarray[j][0] != '\n')
                {
                        ret = snprintf(tempstring,
                            MAXPATHLEN, "|%s\n", display);
                        if (ret < 0 || ret >= MAXPATHLEN)
                        {
                                fclose(fp);
                                errx(1, "error while trying to backup %s",
                                    lastwallpaper);
                        }
                        /* If a line matching the current DISPLAY is
                         * found overwrite it. */
                        if (strstr(lstwllpprarray[j], tempstring))
                        {
                                fprintf(fp, "%s|%s|%s\n",
                                    option, wallpaper, display);
                                found = TRUE;
                        }
                        /* or else keep it. */
                        else
                                fprintf(fp, "%s", lstwllpprarray[j]);

                }
                free(lstwllpprarray[j]);
        }
        if (found == FALSE)
                fprintf(fp, "%s|%s|%s\n", option, wallpaper, display);

        if (fclose(fp) != 0)
                err(1, "error");

        free(tempstring);
        return (TRUE);
}