/* Test for ungetc bugs.  */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#undef assert

#define assert(x) \

  if (!(x)) \

    { \

      fputs ("test failed: " #x "\n", stderr); \

      retval = 1; \

      goto the_end; \

    }

int

main (int argc, char *argv[])

{

  char name[] = "/tmp/tst-ungetc.XXXXXX";

  FILE *fp = NULL;

  int retval = 0;

  int c;

  char buffer[64];

  int fd = mkstemp (name);

  if (fd == -1)

    {

      printf ("mkstemp failed: %m\n");

      return 1;

    }

  close (fd);

  fp = fopen (name, "w");

  assert (fp != NULL)

  fputs ("bla", fp);

  fclose (fp);

  fp = NULL;

  fp = fopen (name, "r");

  assert (fp != NULL);

  assert (ungetc ('z', fp) == 'z');

  assert (getc (fp) == 'z');

  assert (getc (fp) == 'b');

  assert (getc (fp) == 'l');

  assert (ungetc ('m', fp) == 'm');

  assert (getc (fp) == 'm');

  assert ((c = getc (fp)) == 'a');

  assert (getc (fp) == EOF);

  assert (ungetc (c, fp) == c);

  assert (feof (fp) == 0);

  assert (getc (fp) == c);

  assert (getc (fp) == EOF);

  fclose (fp);

  fp = NULL;

  fp = fopen (name, "r");

  assert (fp != NULL);

  assert (getc (fp) == 'b');

  assert (getc (fp) == 'l');

  assert (ungetc ('b', fp) == 'b');

  assert (fread (buffer, 1, 64, fp) == 2);

  assert (buffer[0] == 'b');

  assert (buffer[1] == 'a');

the_end:

  if (fp != NULL)

    fclose (fp);

  unlink (name);

  return retval;

}