stdlib/tst-environ.c

   1 /* Copyright (C) 1999 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23
  24 #define VAR "FOOBAR"
  25
  26 char putenv_val[100] = VAR "=some longer value";
  27
  28 int
  29 main (void)
  30 {
  31   int result = 0;
  32   const char *valp;
  33
  34   /* First test: remove entry FOOBAR, whether it exists or not.  */
  35   unsetenv (VAR);
  36
  37   /* Now getting the value should fail.  */
  38   if (getenv (VAR) != NULL)
  39     {
  40       printf ("There should be no `%s' value\n", VAR);
  41       result = 1;
  42     }
  43
  44   /* Now add a value, with the replace flag cleared.  */
  45   if (setenv (VAR, "one", 0) != 0)
  46     {
  47       printf ("setenv #1 failed: %m\n");
  48       result = 1;
  49     }
  50
  51   /* Getting this value should now be possible.  */
  52   valp = getenv (VAR);
  53   if (valp == NULL || strcmp (valp, "one") != 0)
  54     {
  55       puts ("getenv #2 failed");
  56       result = 1;
  57     }
  58
  59   /* Try to replace without the replace flag set.  This should fail.  */
  60   if (setenv (VAR, "two", 0) != 0)
  61     {
  62       printf ("setenv #2 failed: %m\n");
  63       result = 1;
  64     }
  65
  66   /* The value shouldn't have changed.  */
  67   valp = getenv (VAR);
  68   if (valp == NULL || strcmp (valp, "one") != 0)
  69     {
  70       puts ("getenv #3 failed");
  71       result = 1;
  72     }
  73
  74   /* Now replace the value using putenv.  */
  75   if (putenv (putenv_val) != 0)
  76     {
  77       printf ("putenv #1 failed: %m\n");
  78       result = 1;
  79     }
  80
  81   /* The value should have changed now.  */
  82   valp = getenv (VAR);
  83   if (valp == NULL || strcmp (valp, "some longer value") != 0)
  84     {
  85       printf ("getenv #4 failed (is \"%s\")\n", valp);
  86       result = 1;
  87     }
  88
  89   /* Now one tricky check: changing the variable passed in putenv should
  90      change the environment.  */
  91   strcpy (&putenv_val[sizeof VAR], "a short one");
  92
  93   /* The value should have changed again.  */
  94   valp = getenv (VAR);
  95   if (valp == NULL || strcmp (valp, "a short one") != 0)
  96     {
  97       puts ("getenv #5 failed");
  98       result = 1;
  99     }
 100
 101   /* It should even be possible to rename the variable.  */
 102   strcpy (putenv_val, "XYZZY=some other value");
 103
 104   /* Now a lookup using the old name should fail.  */
 105   if (getenv (VAR) != NULL)
 106     {
 107       puts ("getenv #6 failed");
 108       result = 1;
 109     }
 110
 111   /* But using the new name it should work.  */
 112   valp = getenv ("XYZZY");
 113   if (valp == NULL || strcmp (valp, "some other value") != 0)
 114     {
 115       puts ("getenv #7 failed");
 116       result = 1;
 117     }
 118
 119   /* Create a new variable with the old name.  */
 120   if (setenv (VAR, "a new value", 0) != 0)
 121     {
 122       printf ("setenv #3 failed: %m\n");
 123       result = 1;
 124     }
 125
 126   /* At this point a getenv call must return the new value.  */
 127   valp = getenv (VAR);
 128   if (valp == NULL || strcmp (valp, "a new value") != 0)
 129     {
 130       puts ("getenv #8 failed");
 131       result = 1;
 132     }
 133
 134   /* Black magic: rename the variable we added using putenv back.  */
 135   strcpy (putenv_val, VAR "=old name new value");
 136
 137   /* This is interesting.  We have two variables with the same name.
 138      Getting a value should return one of them.  */
 139   valp = getenv (VAR);
 140   if (valp == NULL
 141       || (strcmp (valp, "a new value") != 0
 142           && strcmp (valp, "old name new value") != 0))
 143     {
 144       puts ("getenv #9 failed");
 145       result = 1;
 146     }
 147
 148   /* More fun ahead: we are now removing the variable.  This should remove
 149      both values.  The cast is ok: this call should never put the string
 150      in the environment and it should never modify it.  */
 151   putenv ((char *) VAR);
 152
 153   /* Getting the value should now fail.  */
 154   if (getenv (VAR) != NULL)
 155     {
 156       printf ("getenv #10 failed (\"%s\" found)\n", getenv (VAR));
 157       result = 1;
 158     }
 159
 160   /* Now a test with an environment variable that's one character long.
 161      This is to test a special case in the getenv implementation.  */
 162   strcpy (putenv_val, "X=one character test");
 163   if (putenv (putenv_val) != 0)
 164     {
 165       printf ("putenv #2 failed: %m\n");
 166       result = 1;
 167     }
 168
 169   valp = getenv ("X");
 170   if (valp == NULL || strcmp (valp, "one character test") != 0)
 171     {
 172       puts ("getenv #11 failed");
 173       result = 1;
 174     }
 175
 176   return result;
 177 }