io/tst-fcntl.c

   1 /* Tests for fcntl.
   2    Copyright (C) 2000-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <fcntl.h>
  21 #include <paths.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <sys/stat.h>
  25
  26
  27 /* Prototype for our test function.  */
  28 extern void do_prepare (int argc, char *argv[]);
  29 extern int do_test (int argc, char *argv[]);
  30
  31 /* We have a preparation function.  */
  32 #define PREPARE do_prepare
  33
  34 #include "../test-skeleton.c"
  35
  36
  37 /* Name of the temporary files.  */
  38 static char *name;
  39
  40 /* File descriptor to temporary file.  */
  41 static int fd;
  42
  43 void
  44 do_prepare (int argc, char *argv[])
  45 {
  46    size_t name_len;
  47
  48    name_len = strlen (test_dir);
  49    name = xmalloc (name_len + sizeof ("/fcntlXXXXXX"));
  50    mempcpy (mempcpy (name, test_dir, name_len),
  51             "/fcntlXXXXXX", sizeof ("/fcntlXXXXXX"));
  52   /* Create the temporary file.  */
  53   fd = mkstemp (name);
  54   if (fd == -1)
  55     {
  56       printf ("cannot open temporary file: %m\n");
  57       exit (1);
  58     }
  59    add_temp_file (name);
  60 }
  61
  62
  63 int
  64 do_test (int argc, char *argv[])
  65 {
  66   int fd2;
  67   int fd3;
  68   struct stat64 st;
  69   int val;
  70   int result = 0;
  71
  72   if (fstat64 (fd, &st) != 0)
  73     {
  74       printf ("cannot stat test file: %m\n");
  75       return 1;
  76     }
  77   if (! S_ISREG (st.st_mode) || st.st_size != 0)
  78     {
  79       puts ("file not created correctly");
  80       return 1;
  81     }
  82
  83   /* Get the flags with fcntl().  */
  84   val = fcntl (fd, F_GETFL);
  85   if (val == -1)
  86     {
  87       printf ("fcntl(fd, F_GETFL) failed: %m\n");
  88       result = 1;
  89     }
  90   else if ((val & O_ACCMODE) != O_RDWR)
  91     {
  92       puts ("temporary file not opened for read and write");
  93       result = 1;
  94     }
  95
  96   /* Set the flags to something else.  */
  97   if (fcntl (fd, F_SETFL, O_RDONLY) == -1)
  98     {
  99       printf ("fcntl(fd, F_SETFL, O_RDONLY) failed: %m\n");
 100       result = 1;
 101     }
 102
 103   val = fcntl (fd, F_GETFL);
 104   if (val == -1)
 105     {
 106       printf ("fcntl(fd, F_GETFL) after F_SETFL failed: %m\n");
 107       result = 1;
 108     }
 109   else if ((val & O_ACCMODE) != O_RDWR)
 110     {
 111       puts ("temporary file access mode changed");
 112       result = 1;
 113     }
 114
 115   /* Set the flags to something else.  */
 116   if (fcntl (fd, F_SETFL, O_APPEND) == -1)
 117     {
 118       printf ("fcntl(fd, F_SETFL, O_APPEND) failed: %m\n");
 119       result = 1;
 120     }
 121
 122   val = fcntl (fd, F_GETFL);
 123   if (val == -1)
 124     {
 125       printf ("fcntl(fd, F_GETFL) after second F_SETFL failed: %m\n");
 126       result = 1;
 127     }
 128   else if ((val & O_APPEND) == 0)
 129     {
 130       puts ("O_APPEND not set");
 131       result = 1;
 132     }
 133
 134   val = fcntl (fd, F_GETFD);
 135   if (val == -1)
 136     {
 137       printf ("fcntl(fd, F_GETFD) failed: %m\n");
 138       result = 1;
 139     }
 140   else if (fcntl (fd, F_SETFD, val | FD_CLOEXEC) == -1)
 141     {
 142       printf ("fcntl(fd, F_SETFD, FD_CLOEXEC) failed: %m\n");
 143       result = 1;
 144     }
 145   else
 146     {
 147       val = fcntl (fd, F_GETFD);
 148       if (val == -1)
 149         {
 150           printf ("fcntl(fd, F_GETFD) after F_SETFD failed: %m\n");
 151           result = 1;
 152         }
 153       else if ((val & FD_CLOEXEC) == 0)
 154         {
 155           puts ("FD_CLOEXEC not set");
 156           result = 1;
 157         }
 158     }
 159
 160   /* Get a number of a free descriptor.  If /dev/null is not available
 161      don't continue testing.  */
 162   fd2 = open (_PATH_DEVNULL, O_RDWR);
 163   if (fd2 == -1)
 164     return result;
 165   close (fd2);
 166
 167   fd3 = fcntl (fd, F_DUPFD, fd2 + 1);
 168   if (fd3 == -1)
 169     {
 170       printf ("fcntl(fd, F_DUPFD, %d) failed: %m\n", fd2 + 1);
 171       result = 1;
 172     }
 173   else if (fd3 <= fd2)
 174     {
 175       printf ("F_DUPFD returned %d which is not larger than %d\n", fd3, fd2);
 176       result = 1;
 177     }
 178
 179   if (fd3 != -1)
 180     {
 181       val = fcntl (fd3, F_GETFD);
 182       if (val == -1)
 183         {
 184           printf ("fcntl(fd3, F_GETFD) after F_DUPFD failed: %m\n");
 185           result = 1;
 186         }
 187       else if ((val & FD_CLOEXEC) != 0)
 188         {
 189           puts ("FD_CLOEXEC still set");
 190           result = 1;
 191         }
 192
 193       close (fd3);
 194     }
 195
 196   return result;
 197 }