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/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
* Copyright (c) 2014, gperftools Contributors
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef GETENV_SAFE_H
#define GETENV_SAFE_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* This getenv function is safe to call before the C runtime is initialized.
* On Windows, it utilizes GetEnvironmentVariable() and on unix it uses
* /proc/self/environ instead calling getenv(). It's intended to be used in
* routines that run before main(), when the state required for getenv() may
* not be set up yet. In particular, errno isn't set up until relatively late
* (after the pthreads library has a chance to make it threadsafe), and
* getenv() doesn't work until then.
* On some platforms, this call will utilize the same, static buffer for
* repeated GetenvBeforeMain() calls. Callers should not expect pointers from
* this routine to be long lived.
* Note that on unix, /proc only has the environment at the time the
* application was started, so this routine ignores setenv() calls/etc. Also
* note it only reads the first 16K of the environment.
*
* NOTE: this is version of GetenvBeforeMain that's usable from
* C. Implementation is in sysinfo.cc
*/
const char* TCMallocGetenvSafe(const char* name);
#ifdef __cplusplus
}
#endif
#endif