/*
 * Diverses constructions d'un tableau de tubes
 *
 * Edouard.Thiel@lif.univ-mrs.fr - 2/10/2013
 *
 * This program is free software under the terms of the
 * GNU Lesser General Public License (LGPL) version 2.1.
*/

/*
  Usage : recopier dans la console :

  for ((i = 1; i <= 7; i++)); do
    gcc -Wall -W -std=c99 tab-tubes.c -o tab-tubes -DMETHODE_$i && ./tab-tubes
  done
*/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>


#ifdef METHODE_1


#define TUBMAX 10

void ouvrir_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i][0]); close (tubes[i][1]);
    }
}

int main () {
    int tubes[TUBMAX][2], ntubes = 5;

    printf ("Méthode 1 : tableau de taille constante\n");

    assert (ntubes <= TUBMAX);

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_2


void ouvrir_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i][0]); close (tubes[i][1]);
    }
}

int main () {

    /* La déclaration de tableaux de taille variable est
       autorisée en C99, voir :
       http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html
    */
    int ntubes = 5, tubes[ntubes][2];

    printf ("Méthode 2 : tableau de taille donnée\n");

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_3


typedef int Tube[2];

void ouvrir_tubes (Tube *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (Tube *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i][0]); close (tubes[i][1]);
    }
}

int main () {
    Tube *tubes; int ntubes = 5;

    printf ("Méthode 3 : tableau dynamique avec un typedef\n");

    tubes = malloc (ntubes * sizeof *tubes);
    if (tubes == NULL) { perror ("malloc"); exit (1); }

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    free (tubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_4


void ouvrir_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (int tubes[][2], int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i][0]); close (tubes[i][1]);
    }
}

int main () {
    int (*tubes)[2], ntubes = 5;

    printf ("Méthode 4 : tableau dynamique de dimension 2\n");

    tubes = malloc (ntubes * sizeof *tubes);
    if (tubes == NULL) { perror ("malloc"); exit (1); }

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    free (tubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_5


void ouvrir_tubes (int **tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (int **tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i][0]); close (tubes[i][1]);
    }
}

int main () {
    int **tubes, ntubes = 5;

    printf ("Méthode 5 : tableau de tableaux dynamiques\n");

    tubes = malloc (ntubes * sizeof *tubes);
    if (tubes == NULL) { perror ("malloc"); exit (1); }

    for (int i = 0; i < ntubes; i++) {
        tubes[i] = malloc (2 * sizeof **tubes);
        if (tubes[i] == NULL) { perror ("malloc"); exit (1); }
    }

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    for (int i = 0; i < ntubes; i++) free (tubes[i]);
    free (tubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_6


void ouvrir_tubes (int *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(&tubes[i*2]) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (int *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i*2+0]); close (tubes[i*2+1]);
    }
}

int main () {
    int *tubes, ntubes = 5;

    printf ("Méthode 6 : tableau dynamique à plat\n");

    tubes = malloc (ntubes*2 * sizeof *tubes);
    if (tubes == NULL) { perror ("malloc"); exit (1); }

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    free (tubes);

    printf ("succès\n");
    exit (0);
}


#elif defined METHODE_7

typedef struct {
    int fds[2];
} Tubes;

void ouvrir_tubes (Tubes *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++)
        if (pipe(tubes[i].fds) < 0) {
            perror ("pipe"); exit (1);
        }
}

void fermer_tubes (Tubes *tubes, int ntubes)
{
    for (int i = 0; i < ntubes; i++) {
        close (tubes[i].fds[0]); close (tubes[i].fds[1]);
    }
}

int main () {
    Tubes *tubes; int ntubes = 5;

    printf ("Méthode 7 : tableau dynamique de structs\n");

    tubes = malloc (ntubes * sizeof *tubes);
    if (tubes == NULL) { perror ("malloc"); exit (1); }

    ouvrir_tubes (tubes, ntubes);
    fermer_tubes (tubes, ntubes);

    free (tubes);

    printf ("succès\n");
    exit (0);
}


#endif  /* METHODE_x */