text: // 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 <unistd.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 = 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
  