none/tests/rlimit_nofile.c

   1 #include <errno.h>
   2 #include <fcntl.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <sys/time.h>
   6 #include <sys/resource.h>
   7 #include <unistd.h>
   8 #include "fdleak.h"
   9 #include "config.h"
  10
  11 int main(int argc, char **argv)
  12 {
  13    struct rlimit oldrlim;
  14    struct rlimit newrlim;
  15    int fd;
  16
  17    CLOSE_INHERITED_FDS;
  18
  19    if (getrlimit(RLIMIT_NOFILE, &oldrlim) < 0)
  20    {
  21       perror("getrlimit");
  22       exit(1);
  23    }
  24
  25    int expected_errno;
  26 #if defined(VGO_freebsd)
  27    expected_errno = EPERM;
  28 #else
  29    expected_errno = EINVAL;
  30 #endif
  31    newrlim.rlim_cur = oldrlim.rlim_max+1;
  32    newrlim.rlim_max = oldrlim.rlim_max;
  33    if (setrlimit(RLIMIT_NOFILE, &newrlim) == -1)
  34    {
  35       if (errno != expected_errno) {
  36 #if defined(VGO_freebsd)
  37          fprintf(stderr, "setrlimit exceeding hardlimit must set errno=EPERM\n");
  38 #else
  39          fprintf(stderr, "setrlimit exceeding hardlimit must set errno=EINVAL\n");
  40 #endif
  41          exit(1);
  42       }
  43    }
  44    else
  45    {
  46         fprintf(stderr, "setrlimit exceeding hardlimit must return -1\n");
  47         exit(1);
  48    }
  49
  50    newrlim.rlim_cur = oldrlim.rlim_max;
  51    newrlim.rlim_max = oldrlim.rlim_max+1;
  52    if (setrlimit(RLIMIT_NOFILE, &newrlim) == -1)
  53    {
  54       if (errno != EPERM) {
  55          fprintf(stderr, "setrlimit changing hardlimit must set errno=EPERM\n");
  56          exit(1);
  57       }
  58    }
  59    else
  60    {
  61         fprintf(stderr, "setrlimit changing hardlimit must return -1\n");
  62         exit(1);
  63    }
  64
  65    newrlim.rlim_cur = oldrlim.rlim_cur / 2;
  66    newrlim.rlim_max = oldrlim.rlim_max;
  67
  68    if (setrlimit(RLIMIT_NOFILE, &newrlim) < 0)
  69    {
  70       perror("setrlimit");
  71       exit(1);
  72    }
  73
  74    if (getrlimit(RLIMIT_NOFILE, &newrlim) < 0)
  75    {
  76       perror("getrlimit");
  77       exit(1);
  78    }
  79
  80    if (newrlim.rlim_cur != oldrlim.rlim_cur / 2)
  81    {
  82       fprintf(stderr, "rlim_cur is %llu (should be %llu)\n",
  83               (unsigned long long)newrlim.rlim_cur,
  84               (unsigned long long)oldrlim.rlim_cur / 2);
  85    }
  86
  87    if (newrlim.rlim_max != oldrlim.rlim_max)
  88    {
  89       fprintf(stderr, "rlim_max is %llu (should be %llu)\n",
  90               (unsigned long long)newrlim.rlim_max,
  91               (unsigned long long)oldrlim.rlim_max);
  92    }
  93
  94    newrlim.rlim_cur -= 3; /* allow for stdin, stdout and stderr */
  95
  96    while (newrlim.rlim_cur-- > 0)
  97    {
  98       if (open("/dev/null", O_RDONLY) < 0)
  99       {
 100          perror("open");
 101       }
 102    }
 103
 104    if ((fd = open("/dev/null", O_RDONLY)) >= 0)
 105    {
 106       fprintf(stderr, "open succeeded with fd %d - it should have failed!\n", fd);
 107    }
 108    else if (errno != EMFILE)
 109    {
 110       perror("open");
 111    }
 112
 113    /* We used to test setrlimit(RLIMIT_NOFILE, NULL) -1 || errno != EFAULT,
 114       but glibc doesn't give any guarantees that won't just crash, in
 115       newer versions it just silently succeeds... See bug #385912. */
 116
 117    exit(0);
 118 }