history.c

#include "shell.h"


/**

 * tellhistory - gets the history file

 * @info: parameter struct

 *

 * Return: allocated string containg history file

 */


char *tellhistory(info_t *info)

{

        char *buf, *dir;


        dir = _getenv(info, "HOME=");

        if (!dir)

                return (NULL);

        buf = malloc(sizeof(char) * (len(dir) + len(HIST_FILE) + 2));

        if (!buf)

                return (NULL);

        buf[0] = 0;

        _strcpy(buf, dir);

        _strcat(buf, "/");

        _strcat(buf, HIST_FILE);

        return (buf);

}


/**

 * apped_hist - creates a file, or appends to an existing file

 * @info: the parameter struct

 *

 * Return: 1 on success, else -1

 */

int apped_hist(info_t *info)

{

        ssize_t fd;

        char *filename = tellhistory(info);

        list_t *node = NULL;


        if (!filename)

                return (-1);


        fd = open(filename, O_CREAT | O_TRUNC | O_RDWR, 0644);

        free(filename);

        if (fd == -1)

                return (-1);

        for (node = info->history; node; node = node->next)

        {

                _putsfdsc(node->str, fd);

                _putfdsc('\n', fd);

        }

        _putfdsc(BUF_FLUSH, fd);

        close(fd);

        return (1);

}


/**

 * histread - reads history from file

 * @info: the parameter struct

 *

 * Return: histcount on success, 0 otherwise

 */

int histread(info_t *info)

{

        int i, last = 0, linecount = 0;

        ssize_t fd, rdlen, fsize = 0;

        struct stat st;

        char *buf = NULL, *filename = tellhistory(info);


        if (!filename)

                return (0);


        fd = open(filename, O_RDONLY);

        free(filename);

        if (fd == -1)

                return (0);

        if (!fstat(fd, &st))

                fsize = st.st_size;

        if (fsize < 2)

                return (0);

        buf = malloc(sizeof(char) * (fsize + 1));

        if (!buf)

                return (0);

        rdlen = read(fd, buf, fsize);

        buf[fsize] = 0;

        if (rdlen <= 0)

                return (free(buf), 0);

        close(fd);

        for (i = 0; i < fsize; i++)

                if (buf[i] == '\n')

                {

                        buf[i] = 0;

                        historybuild(info, buf + last, linecount++);

                        last = i + 1;

                }

        if (last != i)

                historybuild(info, buf + last, linecount++);

        free(buf);

        info->histcount = linecount;

        while (info->histcount-- >= HIST_MAX)

                indexdelete_node(&(info->history), 0);

        renum_hist(info);

        return (info->histcount);

}


/**

 * historybuild - adds entry to a history linked list

 * @info: Structure containing potential arguments. Used to maintain

 * @buf: buffer

 * @linecount: the history linecount, histcount

 *

 * Return: Always 0

 */

int historybuild(info_t *info, char *buf, int linecount)

{

        list_t *node = NULL;


        if (info->history)

                node = info->history;

        endadd_node_end(&node, buf, linecount);


        if (!info->history)

                info->history = node;

        return (0);

}


/**

 * renum_hist - renumbers the history linked list after changes

 * @info: Structure containing potential arguments. Used to maintain

 *

 * Return: the new histcount

 */

int renum_hist(info_t *info)

{

        list_t *node = info->history;

        int i = 0;


        while (node)

        {

                node->num = i++;

                node = node->next;

        }

        return (info->histcount = i);

}