[committed] libstdc++: Fix create_directories to resolve symlinks [PR101510]

[Jonathan Wakely <jwakely@redhat.com>]

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On 20/07/21 12:59 +0100, Jonathan Wakely wrote:
>Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
>
>libstdc++-v3/ChangeLog:
>
>	PR libstdc++/101510
>	* src/c++17/fs_ops.cc (create_dir): Adjust whitespace.
>	* testsuite/27_io/filesystem/operations/create_directory.cc:
>	Test creating directory with name of existing symlink to
>	directory.
>	* testsuite/experimental/filesystem/operations/create_directory.cc:
>	Likewise.
>

It turned out this bug report wasn't actually about create_directory,
but create_directories, which does have a bug.

     When filesystem__create_directories checks to see if the path already
     exists and resovles to a directory, it uses filesystem::symlink_status,
     which means it reports an error if the path is a symlink. It should use
     filesystem::status, so that the target directory is detected, and no
     error is reported.
     
     Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
     
     libstdc++-v3/ChangeLog:
     
             PR libstdc++/101510
             * src/c++17/fs_ops.cc (fs::create_directories): Use status
             instead of symlink_status.
             * src/filesystem/ops.cc (fs::create_directories): Likewise.
             * testsuite/27_io/filesystem/operations/create_directories.cc:
             * testsuite/27_io/filesystem/operations/create_directory.cc: Do
             not test with symlinks on Windows.
             * testsuite/experimental/filesystem/operations/create_directories.cc:
             * testsuite/experimental/filesystem/operations/create_directory.cc:
             Do not test with symlinks on Windows.


Tested powerpc64le-linux. Committed to trunk.



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commit 124eaa50e0a34f5f89572c1aa812c50979da58fc
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Jul 20 18:15:48 2021

    libstdc++: Fix create_directories to resolve symlinks [PR101510]
    
    When filesystem__create_directories checks to see if the path already
    exists and resovles to a directory, it uses filesystem::symlink_status,
    which means it reports an error if the path is a symlink. It should use
    filesystem::status, so that the target directory is detected, and no
    error is reported.
    
    Signed-off-by: Jonathan Wakely <jwakely@redhat.com>
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/101510
            * src/c++17/fs_ops.cc (fs::create_directories): Use status
            instead of symlink_status.
            * src/filesystem/ops.cc (fs::create_directories): Likewise.
            * testsuite/27_io/filesystem/operations/create_directories.cc:
            * testsuite/27_io/filesystem/operations/create_directory.cc: Do
            not test with symlinks on Windows.
            * testsuite/experimental/filesystem/operations/create_directories.cc:
            * testsuite/experimental/filesystem/operations/create_directory.cc:
            Do not test with symlinks on Windows.

diff --git a/libstdc++-v3/src/c++17/fs_ops.cc b/libstdc++-v3/src/c++17/fs_ops.cc
index cec76446f06..ceaf0291d64 100644
--- a/libstdc++-v3/src/c++17/fs_ops.cc
+++ b/libstdc++-v3/src/c++17/fs_ops.cc
@@ -496,7 +496,7 @@ fs::create_directories(const path& p, error_code& ec)
       return false;
     }
 
-  file_status st = symlink_status(p, ec);
+  file_status st = status(p, ec);
   if (is_directory(st))
     return false;
   else if (ec && !status_known(st))
diff --git a/libstdc++-v3/src/filesystem/ops.cc b/libstdc++-v3/src/filesystem/ops.cc
index c400376d224..7c5b164fb7f 100644
--- a/libstdc++-v3/src/filesystem/ops.cc
+++ b/libstdc++-v3/src/filesystem/ops.cc
@@ -426,7 +426,7 @@ fs::create_directories(const path& p, error_code& ec) noexcept
       return false;
     }
 
-  file_status st = symlink_status(p, ec);
+  file_status st = status(p, ec);
   if (is_directory(st))
     return false;
   else if (ec && !status_known(st))
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directories.cc b/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directories.cc
index 393d6a55309..304c1453afe 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directories.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directories.cc
@@ -145,10 +145,33 @@ test03()
   remove_all(p);
 }
 
+void
+test04()
+{
+#if defined(__MINGW32__) || defined(__MINGW64__)
+  // no symlinks
+#else
+  // PR libstdc++/101510
+  // create_directories reports an error if the path is a symlink to a dir
+  std::error_code ec = make_error_code(std::errc::invalid_argument);
+  const auto p = __gnu_test::nonexistent_path() / "";
+  fs::create_directories(p/"dir");
+  auto link = p/"link";
+  fs::create_directory_symlink("dir", link);
+  bool created = fs::create_directories(link, ec);
+  VERIFY( !created );
+  VERIFY( !ec );
+  created = fs::create_directories(link);
+  VERIFY( !created );
+  remove_all(p);
+#endif
+}
+
 int
 main()
 {
   test01();
   test02();
   test03();
+  test04();
 }
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directory.cc b/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directory.cc
index 256621481d7..afddccf5ed6 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directory.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/operations/create_directory.cc
@@ -70,6 +70,9 @@ test01()
     VERIFY( e.path1() == f );
   }
 
+#if defined(__MINGW32__) || defined(__MINGW64__)
+  // no symlinks
+#else
   // PR libstdc++/101510 create_directory on an existing symlink to a directory
   fs::create_directory(p/"dir");
   auto link = p/"link";
@@ -80,6 +83,7 @@ test01()
   VERIFY( !ec );
   b = fs::create_directory(link);
   VERIFY( !b );
+#endif
 
   remove_all(p, ec);
 }
diff --git a/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directories.cc b/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directories.cc
index fb264002b69..fc134ad64a3 100644
--- a/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directories.cc
+++ b/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directories.cc
@@ -129,10 +129,33 @@ test03()
   remove_all(p);
 }
 
+void
+test04()
+{
+#if defined(__MINGW32__) || defined(__MINGW64__)
+  // no symlinks
+#else
+  // PR libstdc++/101510
+  // create_directories reports an error if the path is a symlink to a dir
+  std::error_code ec = make_error_code(std::errc::invalid_argument);
+  const auto p = __gnu_test::nonexistent_path() / "";
+  fs::create_directories(p/"dir");
+  auto link = p/"link";
+  fs::create_directory_symlink("dir", link);
+  bool created = fs::create_directories(link, ec);
+  VERIFY( !created );
+  VERIFY( !ec );
+  created = fs::create_directories(link);
+  VERIFY( !created );
+  remove_all(p);
+#endif
+}
+
 int
 main()
 {
   test01();
   test02();
   test03();
+  test04();
 }
diff --git a/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directory.cc b/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directory.cc
index 39f95b61a45..8e36b762a25 100644
--- a/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directory.cc
+++ b/libstdc++-v3/testsuite/experimental/filesystem/operations/create_directory.cc
@@ -69,6 +69,9 @@ test01()
     VERIFY( e.path1() == f );
   }
 
+#if defined(__MINGW32__) || defined(__MINGW64__)
+  // no symlinks
+#else
   // PR libstdc++/101510 create_directory on an existing symlink to a directory
   fs::create_directory(p/"dir");
   auto link = p/"link";
@@ -79,6 +82,7 @@ test01()
   VERIFY( !ec );
   b = fs::create_directory(link);
   VERIFY( !b );
+#endif
 
   remove_all(p, ec);
 }