kira123

#define _GNU_SOURCE
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>


void prompt() {
    char hostname[1024];
    hostname[1023] = '\0';
    gethostname(hostname, 1023);
    char pwd[1024];

    getcwd(pwd, sizeof (pwd));
    printf("%s@%s/%s$", getlogin(), hostname, pwd);
}
void cd(char *argv[]) {
    if(argv[1] == NULL) {
        const char* home = getenv("HOME");
        printf("%s", home);
        chdir(home);
    } else {
        chdir(argv[1]);
    }
}
void help() {
    printf("Helping\n");
}

void help1() {
    printf("Helping\n");
}

int main() {
    char *line = NULL;
    size_t len;
    ssize_t nread;
    int status = 0;
    while (1) {
        // prompt
        if (status != 0 && WIFEXITED(status))
            printf("(\033[31m%d\033[0m) ", WEXITSTATUS(status));
        prompt();

        // read the line and strip newline
        nread = getline(&line, &len, stdin);
        if (nread == -1)
            break;
        if (line[nread-1] == '\n')
            line[nread-1] = '\0';

        // change spaces into zero bytes
        // and initialize argv
        char *argv[100] = { 0 };
        char *p = line;
        int i = 0;
        while (*p) {
            argv[i] = p;
            ++i;
            while (*p && *p != ' ')
                ++p;
            if (*p == ' ')
                *p = '\0';
            ++p;
        }
        if(strcmp(argv[0], "cd") == 0) {
            cd(argv);
        }
        else if(strcmp(argv[0], "help") == 0) {
            help();
        }
        else if(strcmp(argv[0], "exit") == 0) {
            exit(0);
        }
        else if (memchr(argv[0], '=', sizeof(argv[0]))){
            putenv(argv[0]);
        }
        else {
            if (fork()) {
                // parent
                wait(&status);
            } else {
                //child
                execvp(argv[0], argv);
                printf("command not found: %s\n", argv[0]);
                return 1;
            }
        }
    }
    return 0;
}