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 // Copyright (c) 2011, Google Inc.

 // 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.

 // safe_readlink.h: Define the google_breakpad::SafeReadLink function,

 // which wraps sys_readlink and gurantees the result is NULL-terminated.

 #ifndef COMMON_LINUX_SAFE_READLINK_H_

 #define COMMON_LINUX_SAFE_READLINK_H_

 #include <stddef.h>

 namespace google_breakpad {

 // This function wraps sys_readlink() and performs the same functionalty,

 // but guarantees |buffer| is NULL-terminated if sys_readlink() returns

 // no error. It takes the same arguments as sys_readlink(), but unlike

 // sys_readlink(), it returns true on success.

 //

 // |buffer_size| specifies the size of |buffer| in bytes. As this function

 // always NULL-terminates |buffer| on success, |buffer_size| should be

 // at least one byte longer than the expected path length (e.g. PATH_MAX,

 // which is typically defined as the maximum length of a path name

 // including the NULL byte).

 //

 // The implementation of this function calls sys_readlink() instead of

 // readlink(), it can thus be used in the context where calling to libc

 // functions is discouraged.

 bool SafeReadLink(const char* path, char* buffer, size_t buffer_size);

 // Same as the three-argument version of SafeReadLink() but deduces the

 // size of |buffer| if it is a char array of known size.

 template <size_t N>

 bool SafeReadLink(const char* path, char (&buffer)[N]) {

   return SafeReadLink(path, buffer, sizeof(buffer));

 }

 }  // namespace google_breakpad

 #endif  // COMMON_LINUX_SAFE_READLINK_H_