Line data    Source code

       1             : // Copyright (c) 2011, Google Inc.
       2             : // All rights reserved.
       3             : //
       4             : // Redistribution and use in source and binary forms, with or without
       5             : // modification, are permitted provided that the following conditions are
       6             : // met:
       7             : //
       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
      11             : // copyright notice, this list of conditions and the following disclaimer
      12             : // in the documentation and/or other materials provided with the
      13             : // distribution.
      14             : //     * Neither the name of Google Inc. nor the names of its
      15             : // contributors may be used to endorse or promote products derived from
      16             : // this software without specific prior written permission.
      17             : //
      18             : // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      19             : // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      20             : // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      21             : // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      22             : // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      23             : // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      24             : // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      25             : // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      26             : // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      27             : // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      28             : // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      29             : 
      30             : // safe_readlink.cc: Implement google_breakpad::SafeReadLink.
      31             : // See safe_readlink.h for details.
      32             : 
      33             : #include <stddef.h>
      34             : 
      35             : #include "third_party/lss/linux_syscall_support.h"
      36             : 
      37             : namespace google_breakpad {
      38             : 
      39           0 : bool SafeReadLink(const char* path, char* buffer, size_t buffer_size) {
      40             :   // sys_readlink() does not add a NULL byte to |buffer|. In order to return
      41             :   // a NULL-terminated string in |buffer|, |buffer_size| should be at least
      42             :   // one byte longer than the expected path length. Also, sys_readlink()
      43             :   // returns the actual path length on success, which does not count the
      44             :   // NULL byte, so |result_size| should be less than |buffer_size|.
      45           0 :   ssize_t result_size = sys_readlink(path, buffer, buffer_size);
      46           0 :   if (result_size >= 0 && static_cast<size_t>(result_size) < buffer_size) {
      47           0 :     buffer[result_size] = '\0';
      48           0 :     return true;
      49             :   }
      50           0 :   return false;
      51             : }
      52             : 
      53             : }  // namespace google_breakpad