projet-systeme-exploitation-centralise/minishell.c

#define _GNU_SOURCE

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <setjmp.h>
#include "readcmd.h"
#include "jobs.h"

int prompting = 0;
int job_id = 1;
list jobs;

void handler_print(int signal_num, siginfo_t *info)
{
    if (contiens(&jobs, info->si_pid))
    {
        if (prompting)
        {
            printf("\n");
        }
        printf("[%d] --> (%d) %s\n", info->si_pid, signal_num, strsignal(signal_num));
        supprimer(&jobs, info->si_pid);
        job_id--;
    }
}

int main(int argc, char *argv[])
{

    extern int errno;

    initialiser(&jobs);

    struct sigaction action;
    action.sa_flags = SA_SIGINFO; //| SA_RESTART;
    action.sa_handler = handler_print;
    sigemptyset(&action.sa_mask);
    sigaction(SIGCHLD, &action, NULL);

    char initcd[256], currentcd[256];
    getcwd(initcd, 256);

    while (1)
    {
        getcwd(currentcd, 256);
        printf("%s >>> ", currentcd);
        prompting = 1;
        struct cmdline *cmd = readcmd();
        prompting = 0;

        if (cmd == NULL || cmd->seq[0] == NULL)
        { // ligne vide, on skip
            continue;
        }
        else if (!strcmp(cmd->seq[0][0], "exit"))
        { // on quitte le shell
            break;
        }
        else if (!strcmp(cmd->seq[0][0], "cd"))
        { // cd
            if (cmd->seq[0][1] == NULL)
            { // vide
                chdir(initcd);
            }
            else
            { // avec un path
                chdir(cmd->seq[0][1]);
            }
            continue;
        }
        else if (!strcmp(cmd->seq[0][0], "jobs"))
        {
            afficher(&jobs);
            continue;
        }

        pid_t pidFils = fork();

        if (pidFils == -1)
        {
            fprintf(stderr, "ERROR: forking failed, %s\n", strerror(errno));
            exit(errno);
        }

        if (pidFils == 0)
        { // fils
            int test = execvp(cmd->seq[0][0], cmd->seq[0]);
            exit(errno); // si execlp échoue on exit avec une erreur
        }
        else // père
        {
            if (cmd->backgrounded)
            {
                ajouter(&jobs, pidFils, job_id++);
            }
            else
            {
                jmp_buf env;
                setjmp(env);
                
                int codeTerm;
                pid_t idFils = waitpid(pidFils, &codeTerm, 0); // on attend la fin de l'exec du fils

                if (idFils == -1)
                { // si le wait fail
                    if (errno == 4)
                    { // todo : peut mieux faire ?
                        longjmp(env, 1);
                    }
                    else
                    {
                        fprintf(stderr, "ERROR: waiting for %d failed, (%d) %s\n", codeTerm, errno, strerror(errno));
                        exit(errno);
                    }
                }

                if (codeTerm)
                {
                    fprintf(stderr, "ERROR: %d's execution failed, (%d) %s\n", pidFils, codeTerm, strerror(codeTerm));
                }
            }
        }
    }

    return EXIT_SUCCESS;
}