1/* Test program for synchronization of stdio state with file after EOF. */
2
3#include <stdio.h>
4#include <error.h>
5#include <errno.h>
6#include <string.h>
7#include <unistd.h>
8
9static void do_prepare (void);
10#define PREPARE(argc, argv) do_prepare ()
11static int do_test (void);
12#define TEST_FUNCTION do_test ()
13#include <test-skeleton.c>
14
15static char *temp_file;
16static int temp_fd;
17
18static char *pages;
19
20static void
21do_prepare (void)
22{
23 pages = xmalloc (n: getpagesize () * 2);
24 memset (pages, 'a', getpagesize ());
25 memset (pages + getpagesize (), 'b', getpagesize ());
26
27 temp_fd = create_temp_file (base: "tst-mmap2-eofsync.", filename: &temp_file);
28 if (temp_fd == -1)
29 error (status: 1, errno, format: "cannot create temporary file");
30 else
31 {
32 ssize_t cc = write (temp_fd, pages, getpagesize ());
33 if (cc != getpagesize ())
34 error (status: 1, errno, format: "cannot write to temporary file");
35 }
36}
37
38static int
39do_test (void)
40{
41 const size_t pagesize = getpagesize ();
42 FILE *f;
43 char buf[pagesize];
44 int result = 0;
45 int c;
46
47 f = fopen (temp_file, "rm");
48 if (f == NULL)
49 {
50 perror (temp_file);
51 return 1;
52 }
53
54 if (fread (ptr: buf, size: pagesize, n: 1, stream: f) != 1)
55 {
56 perror ("fread");
57 return 1;
58 }
59
60 if (memcmp (buf, pages, pagesize))
61 {
62 puts (s: "data mismatch in page 1");
63 result = 1;
64 }
65
66 printf (format: "feof = %d, ferror = %d immediately after fread\n",
67 feof (stream: f), ferror (stream: f));
68
69 c = fgetc (stream: f);
70 if (c == EOF)
71 printf (format: "fgetc -> EOF (feof = %d, ferror = %d)\n",
72 feof (stream: f), ferror (stream: f));
73 else
74 {
75 printf (format: "fgetc returned %o (feof = %d, ferror = %d)\n",
76 c, feof (stream: f), ferror (stream: f));
77 result = 1;
78 }
79
80 c = write (temp_fd, pages + pagesize, pagesize);
81 if (c == (ssize_t) pagesize)
82 printf (format: "wrote more to file\n");
83 else
84 {
85 printf (format: "wrote %d != %zd (%m)\n", c, pagesize);
86 result = 1;
87 }
88
89 if (fread (ptr: buf, size: pagesize, n: 1, stream: f) != 1)
90 {
91 printf (format: "second fread fails: feof = %d, ferror = %d (%m)\n",
92 feof (stream: f), ferror (stream: f));
93 clearerr (stream: f);
94 if (fread (ptr: buf, size: pagesize, n: 1, stream: f) != 1)
95 {
96 printf (format: "retry fread fails: feof = %d, ferror = %d (%m)\n",
97 feof (stream: f), ferror (stream: f));
98 result = 1;
99 }
100 }
101 if (result == 0 && memcmp (buf, pages + pagesize, pagesize))
102 {
103 puts (s: "data mismatch in page 2");
104 result = 1;
105 }
106
107 fseek (f, pagesize - 1, SEEK_SET);
108 c = fgetc (stream: f);
109 if (c != 'a')
110 {
111 printf (format: "fgetc at end of page 1 read '%c' (%m)\n", c);
112 result = 1;
113 }
114
115 if (ftruncate (fd: temp_fd, length: pagesize) < 0)
116 {
117 printf (format: "ftruncate failed: %m\n");
118 result = 1;
119 }
120
121 fflush (f);
122
123 c = fgetc (stream: f);
124 if (c == EOF)
125 printf (format: "after truncate fgetc -> EOF (feof = %d, ferror = %d)\n",
126 feof (stream: f), ferror (stream: f));
127 else
128 {
129 printf (format: "after truncate fgetc returned '%c' (feof = %d, ferror = %d)\n",
130 c, feof (stream: f), ferror (stream: f));
131 result = 1;
132 }
133
134 fclose (f);
135
136 return result;
137}
138

source code of glibc/libio/tst-mmap2-eofsync.c