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 */ 55