/* Test program for synchronization of stdio state with file after EOF.  */

#include <stdio.h>

#include <error.h>

#include <errno.h>

#include <string.h>

#include <unistd.h>

static void do_prepare (void);

#define PREPARE(argc, argv) do_prepare ()

static int do_test (void);

#define TEST_FUNCTION do_test ()

#include <test-skeleton.c>

static char *temp_file;

static int temp_fd;

static char *pages;

static void

do_prepare (void)

{

  pages = xmalloc (getpagesize () * 2);

  memset (pages, 'a', getpagesize ());

  memset (pages + getpagesize (), 'b', getpagesize ());

  temp_fd = create_temp_file ("tst-mmap2-eofsync.", &temp_file);

  if (temp_fd == -1)

    error (1, errno, "cannot create temporary file");

  else

    {

      ssize_t cc = write (temp_fd, pages, getpagesize ());

      if (cc != getpagesize ())

	error (1, errno, "cannot write to temporary file");

    }

}

static int

do_test (void)

{

  const size_t pagesize = getpagesize ();

  FILE *f;

  char buf[pagesize];

  int result = 0;

  int c;

  f = fopen (temp_file, "rm");

  if (f == NULL)

    {

      perror (temp_file);

      return 1;

    }

  if (fread (buf, pagesize, 1, f) != 1)

    {

      perror ("fread");

      return 1;

    }

  if (memcmp (buf, pages, pagesize))

    {

      puts ("data mismatch in page 1");

      result = 1;

    }

  printf ("feof = %d, ferror = %d immediately after fread\n",

	  feof (f), ferror (f));

  c = fgetc (f);

  if (c == EOF)

    printf ("fgetc -> EOF (feof = %d, ferror = %d)\n",

	    feof (f), ferror (f));

  else

    {

      printf ("fgetc returned %o (feof = %d, ferror = %d)\n",

	      c, feof (f), ferror (f));

      result = 1;

    }

  c = write (temp_fd, pages + pagesize, pagesize);

  if (c == (ssize_t) pagesize)

    printf ("wrote more to file\n");

  else

    {

      printf ("wrote %d != %zd (%m)\n", c, pagesize);

      result = 1;

    }

  if (fread (buf, pagesize, 1, f) != 1)

    {

      printf ("second fread fails: feof = %d, ferror = %d (%m)\n",

	      feof (f), ferror (f));

      clearerr (f);

      if (fread (buf, pagesize, 1, f) != 1)

	{

	  printf ("retry fread fails: feof = %d, ferror = %d (%m)\n",

		  feof (f), ferror (f));

	  result = 1;

	}

    }

  if (result == 0 && memcmp (buf, pages + pagesize, pagesize))

    {

      puts ("data mismatch in page 2");

      result = 1;

    }

  fseek (f, pagesize - 1, SEEK_SET);

  c = fgetc (f);

  if (c != 'a')

    {

      printf ("fgetc at end of page 1 read '%c' (%m)\n", c);

      result = 1;

    }

  if (ftruncate (temp_fd, pagesize) < 0)

    {

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

      result = 1;

    }

  fflush (f);

  c = fgetc (f);

  if (c == EOF)

    printf ("after truncate fgetc -> EOF (feof = %d, ferror = %d)\n",

	    feof (f), ferror (f));

  else

    {

      printf ("after truncate fgetc returned '%c' (feof = %d, ferror = %d)\n",

	      c, feof (f), ferror (f));

      result = 1;

    }

  fclose (f);

  return result;

}