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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.cc: Implement google_breakpad::SafeReadLink.

 // See safe_readlink.h for details.

 #include <stddef.h>

 #include "third_party/lss/linux_syscall_support.h"

 namespace google_breakpad {

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

   // sys_readlink() does not add a NULL byte to |buffer|. In order to return

   // a NULL-terminated string in |buffer|, |buffer_size| should be at least

   // one byte longer than the expected path length. Also, sys_readlink()

   // returns the actual path length on success, which does not count the

   // NULL byte, so |result_size| should be less than |buffer_size|.

   ssize_t result_size = sys_readlink(path, buffer, buffer_size);

   if (result_size >= 0 && static_cast<size_t>(result_size) < buffer_size) {

     buffer[result_size] = '\0';

     return true;

   }

   return false;

 }

 }  // namespace google_breakpad