[Boost-bugs] [Boost C++ Libraries] #12108: boost::filesystem::canonical() enters infinite loop when current path is a directory symlink on windows

Subject: [Boost-bugs] [Boost C++ Libraries] #12108: boost::filesystem::canonical() enters infinite loop when current path is a directory symlink on windows
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-04-01 08:02:02

#12108: boost::filesystem::canonical() enters infinite loop when current path is a
directory symlink on windows
-----------------------------------------+------------------------
 Reporter:  Tony Abbott <tony.abbott@…>  |      Owner:  bemandawes
     Type:  Bugs                         |     Status:  new
Milestone:  To Be Determined             |  Component:  filesystem
  Version:  Boost 1.60.0                 |   Severity:  Problem
 Keywords:                               |
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 On Windows platforms, when the current path is a directory symlink,
 boost::filesystem::canonical() enters an infinite loop.

 Verified using attached program on Windows 8.1 and Windows Server 2012.

 The problem occurs because when the current path is a directory symlink
 then boost::filesystem::is_symlink(path("c:")) returns true.

 Assuming the following paths:

 myDir  = c:\temp\symlink-example\dir
 mySym  = c:\temp\symlink-example\sym -> myDir
 myFile = c:\temp\symlink-example\dir\hello.txt

 When current path is set to mySym and canonical(myFile) is called:

 * The path components of myFile are iterated over (operations.cpp:827)
 * "c:" is the first component. It is considered a symlink and expanded
 (operations.cpp:844)
 * The path then becomes c:\temp\symlink-example\dir\temp\symlink-
 example\dir\hello.txt
 * scan is set true and the loop repeats. "c:" is again expanded. The loop
 repeats infinitely as the path grows longer and longer

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12108>
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