hybris/common/ics/linker_environ.h

   1 /*
   2  * Copyright (C) 2010 The Android Open Source Project
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *  * Redistributions of source code must retain the above copyright
   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
  12  *    the documentation and/or other materials provided with the
  13  *    distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28 #ifndef LINKER_ENVIRON_H
  29 #define LINKER_ENVIRON_H
  30
  31 /* Call this function before anything else. 'vecs' must be the pointer
  32  * to the environment block in the ELF data block. The function returns
  33  * the start of the aux vectors after the env block.
  34  */
  35 extern unsigned*   linker_env_init(unsigned* vecs);
  36
  37 /* Unset a given environment variable. In case the variable is defined
  38  * multiple times, unset all instances. This modifies the environment
  39  * block, so any pointer returned by linker_env_get() after this call
  40  * might become invalid */
  41 extern void        linker_env_unset(const char* name);
  42
  43
  44 /* Returns the value of environment variable 'name' if defined and not
  45  * empty, or NULL otherwise. Note that the returned pointer may become
  46  * invalid if linker_env_unset() or linker_env_secure() are called
  47  * after this function. */
  48 extern const char* linker_env_get(const char* name);
  49
  50 /* Remove unsecure environment variables. This should be used when
  51  * running setuid programs. */
  52 extern void        linker_env_secure(void);
  53
  54 #endif /* LINKER_ENVIRON_H */