external/bsd/kyua-testers/dist/env.c

   1 // Copyright 2012 Google Inc.
   2 // All rights reserved.
   3 //
   4 // Redistribution and use in source and binary forms, with or without
   5 // modification, are permitted provided that the following conditions are
   6 // met:
   7 //
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   9 //   notice, this list of conditions and the following disclaimer.
  10 // * Redistributions in binary form must reproduce the above copyright
  11 //   notice, this list of conditions and the following disclaimer in the
  12 //   documentation and/or other materials provided with the distribution.
  13 // * Neither the name of Google Inc. nor the names of its contributors
  14 //   may be used to endorse or promote products derived from this software
  15 //   without specific prior written permission.
  16 //
  17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28
  29 #if defined(HAVE_CONFIG_H)
  30 #   include "config.h"
  31 #endif
  32
  33 #include "env.h"
  34
  35 #include <assert.h>
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40
  41 #include "error.h"
  42
  43
  44 /// Sets an environment variable.
  45 ///
  46 /// \param name Name of the environment variable to set.
  47 /// \param value Value to be set.
  48 ///
  49 /// \return An error object.
  50 kyua_error_t
  51 kyua_env_set(const char* name, const char* value)
  52 {
  53     kyua_error_t error;
  54
  55 #if defined(HAVE_SETENV)
  56     if (setenv(name, value, 1) == -1)
  57         error = kyua_libc_error_new(
  58             errno, "Failed to set environment variable %s to %s", name, value);
  59     else
  60         error = kyua_error_ok();
  61 #elif defined(HAVE_PUTENV)
  62     const size_t length = strlen(name) + strlen(value) + 2;
  63     char* buffer = (char*)malloc(length);
  64     if (buffer == NULL)
  65         error = kyua_oom_error_new();
  66     else {
  67         const size_t printed_length = snprintf(buffer, length, "%s=%s", name,
  68                                                value);
  69         assert(length == printed_length + 1);
  70         if (putenv(buffer) == -1) {
  71             error = kyua_libc_error_new(
  72                 errno, "Failed to set environment variable %s to %s",
  73                 name, value);
  74             free(buffer);
  75         } else
  76             error = kyua_error_ok();
  77     }
  78 #else
  79 #   error "Don't know how to set an environment variable."
  80 #endif
  81
  82     return error;
  83 }
  84
  85
  86 /// Unsets an environment variable.
  87 ///
  88 /// \param name Name of the environment variable to unset.
  89 ///
  90 /// \return An error object.
  91 kyua_error_t
  92 kyua_env_unset(const char* name)
  93 {
  94 #if defined(HAVE_UNSETENV)
  95     if (unsetenv(name) == -1)
  96         return kyua_libc_error_new(
  97             errno, "Failed to unset environment variable %s", name);
  98     else
  99         return kyua_error_ok();
 100 #elif defined(HAVE_PUTENV)
 101     return kyua_env_set(name, "");
 102 #else
 103 #   error "Don't know how to unset an environment variable."
 104 #endif
 105 }