test virFileOpen

test-virFileOpen.c

/*
  test-virFileOpen.c
  This mimics libvirt/src/lxc/lxc_controller.c in lxcControllerRun

  gcc -o test-virFileOpen test-virFileOpen.c
  mkdir d
  sudo ./test-virFileOpen d

  We get varied results.  Sometimes this passes, sometimes it fails.
*/
#define _XOPEN_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <errno.h>
#define PATH_MAX 4096



int virFileOpenTtyAt(const char *ptmx,
                     int *ttymaster,
                     char **ttyName,
                     int rawmode)
{
    int rc = -1;

    if ((*ttymaster = open(ptmx, O_RDWR|O_NOCTTY|O_NONBLOCK)) < 0) {
        printf("open failed\n");
        goto cleanup;
    }
    printf("opened %s to %i ptsname=%s\n", ptmx, *ttymaster, ptsname(*ttymaster));

    if (unlockpt(*ttymaster) < 0) {
        printf("unlockpt failed\n");
        goto cleanup;
    }

    if (grantpt(*ttymaster) < 0) {
        printf("grantpt failed (%i)\n", errno);
        perror("grantpt");
        goto cleanup;
    }

    if (rawmode) {
        struct termios ttyAttr;
        if (tcgetattr(*ttymaster, &ttyAttr) < 0) {
            printf("tcgetattr failed\n");
            goto cleanup;
        }

        cfmakeraw(&ttyAttr);

        if (tcsetattr(*ttymaster, TCSADRAIN, &ttyAttr) < 0) {
            printf("tcsetattr failed\n");
            goto cleanup;
        }
    }

    if (ttyName) {
        // if (VIR_ALLOC_N(*ttyName, PATH_MAX) < 0) {
        if ((ttyName = malloc(PATH_MAX)) == 0) {
            printf("failed malloc\n");
            errno = ENOMEM;
            goto cleanup;
        }

        if (ptsname_r(*ttymaster, *ttyName, PATH_MAX) < 0) {
            printf("ptsname_r failed\n");
            goto cleanup;
        }
    }

    rc = 0;

cleanup:
    if (rc != 0)
        close(*ttymaster);
        // VIR_FORCE_CLOSE(*ttymaster);

    return rc;

}

int main(int argc, char* argv[]) {
   char *devpts = argv[1];
   char devptmx[4096];
   int containerPty = -1;
   char *containerPtyPath = NULL;

   sprintf(devptmx, "%s/ptmx", devpts);
   printf("devptmx=%s devpts=%s\n", devptmx, devpts);
   if (mount("devpts", devpts, "devpts", 0,
      "newinstance,ptmxmode=0666,mode=0620,gid=5") < 0) {
      printf("mount of %s failed\n", devpts);
      return(1);
   }
   
   if (virFileOpenTtyAt(devptmx,
                        &containerPty,
                        &containerPtyPath,
                        0) < 0) {
       printf("virFileOpenTtyAt failed\n");
       close(containerPty);
       if(umount(devpts) != 0) { perror("umount"); printf("umount failed\n"); }
       return(1);
   }
   close(containerPty);
   if(umount(devpts) != 0) { perror("umount"); printf("umount failed\n"); }

   printf("Everything seems good\n");
}