aboutsummaryrefslogtreecommitdiffstats
path: root/libio/tst-mmap2-eofsync.c
blob: 05dedb8c2066060335242bc3db5745d26e178ae1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
/* 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;
}