progs/shel/shel.c


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#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/wait.h>
#include <stdbool.h>
#include <string.h>

void parseInput(char *input, char *command, char **argv) {
    bool reachedArgv = false;
    char arg[32] = {0};
    int idx = 0;
    int argvIdx = 1;
    
    for (int i = 0; i < strlen(input); i++)
    {
        char *a = {&(input[i])};
        if (reachedArgv) {
            if (input[i] == ' ') {
                arg[idx] = '\0';
                argv[argvIdx] = strdup(arg);
                memset(arg, 0, sizeof(arg));
                argvIdx++;
                idx = 0;
                continue;
            }
            arg[idx] = input[i];
            idx++;
            continue;
        }
        if (input[i] == ' ') {
            arg[idx] = '\0';
            strcpy(command, arg);
            reachedArgv = true;
            memset(arg, 0, sizeof(arg));
            idx = 0;
            continue;
        }
        arg[idx] = input[i];
        idx++;
    }
    argv[0] = command;
    if (reachedArgv) {
        arg[idx] = '\0';
        argv[argvIdx] = strdup(arg);
    }
}

int main() {
    char input[255] = {0};
    char command[128] = {0};
    char *argv[32] = {0};
    char *env[32] = {"PATH=/bin"};
    char path[128] = "/";

    strcpy(input, "/bin/echo meow");
    parseInput(input, command, argv);
    execve(command, argv, 0);
}