libstdc++: Fix error reporting in filesystem::copy [PR99290]

The recursive calls to filesystem::copy should stop if any of them
reports an error.

libstdc++-v3/ChangeLog:

	PR libstdc++/99290
	* src/c++17/fs_ops.cc (fs::copy): Pass error_code to
	directory_iterator constructor, and check on each iteration.
	* src/filesystem/ops.cc (fs::copy): Likewise.
	* testsuite/27_io/filesystem/operations/copy.cc: Check for
	errors during recursion.
	* testsuite/experimental/filesystem/operations/copy.cc:
	Likewise.

4 files changed, 70 insertions, 4 deletions

diff --git a/libstdc++-v3/src/c++17/fs_ops.cc b/libstdc++-v3/src/c++17/fs_ops.cc
index 4552a73..435368f 100644
--- a/libstdc++-v3/src/c++17/fs_ops.cc
+++ b/libstdc++-v3/src/c++17/fs_ops.cc
@@ -408,8 +408,12 @@ fs::copy(const path& from, const path& to, copy_options options,
       // set an unused bit in options to disable further recursion
       if (!is_set(options, copy_options::recursive))
 	options |= static_cast<copy_options>(4096);
-      for (const directory_entry& x : directory_iterator(from))
-	copy(x.path(), to/x.path().filename(), options, ec);
+      for (const directory_entry& x : directory_iterator(from, ec))
+	{
+	  copy(x.path(), to/x.path().filename(), options, ec);
+	  if (ec)
+	    return;
+	}
     }
   // _GLIBCXX_RESOLVE_LIB_DEFECTS
   // 2683. filesystem::copy() says "no effects"
diff --git a/libstdc++-v3/src/filesystem/ops.cc b/libstdc++-v3/src/filesystem/ops.cc
index e2a2cef..98ddff5 100644
--- a/libstdc++-v3/src/filesystem/ops.cc
+++ b/libstdc++-v3/src/filesystem/ops.cc
@@ -350,8 +350,12 @@ fs::copy(const path& from, const path& to, copy_options options,
       // set an unused bit in options to disable further recursion
       if (!is_set(options, copy_options::recursive))
 	options |= static_cast<copy_options>(4096);
-      for (const directory_entry& x : directory_iterator(from))
-	copy(x.path(), to/x.path().filename(), options, ec);
+      for (const directory_entry& x : directory_iterator(from, ec))
+	{
+	  copy(x.path(), to/x.path().filename(), options, ec);
+	  if (ec)
+	    return;
+	}
     }
   // _GLIBCXX_RESOLVE_LIB_DEFECTS
   // 2683. filesystem::copy() says "no effects"
diff --git a/libstdc++-v3/testsuite/27_io/filesystem/operations/copy.cc b/libstdc++-v3/testsuite/27_io/filesystem/operations/copy.cc
index b85628c..b936e04 100644
--- a/libstdc++-v3/testsuite/27_io/filesystem/operations/copy.cc
+++ b/libstdc++-v3/testsuite/27_io/filesystem/operations/copy.cc
@@ -193,6 +193,34 @@ test05()
   VERIFY( !ec );  // Previous value should be cleared (LWG 2683)
 }
 
+void
+test_pr99290()
+{
+  auto dir = __gnu_test::nonexistent_path();
+  auto source = dir/"source";
+  auto dest = dir/"dest";
+  create_directories(source/"emptydir");
+  create_directories(dest/"emptydir");
+  std::ofstream{source/"file"} << 'a';
+  std::ofstream{dest/"file"} << 'b';
+  // PR libstdc++/99290
+  // std::filesystem::copy does not always report errors for recursion
+  std::error_code ec;
+  copy(source, dest, ec);
+  VERIFY( ec == std::errc::file_exists );
+
+#if __cpp_exceptions
+  try {
+    copy(source, dest);
+    VERIFY( false );
+  } catch (const fs::filesystem_error& e) {
+    VERIFY( e.code() == std::errc::file_exists );
+  }
+#endif
+
+  remove_all(dir);
+}
+
 int
 main()
 {
@@ -201,4 +229,5 @@ main()
   test03();
   test04();
   test05();
+  test_pr99290();
 }
diff --git a/libstdc++-v3/testsuite/experimental/filesystem/operations/copy.cc b/libstdc++-v3/testsuite/experimental/filesystem/operations/copy.cc
index 319632a..5cd6b48 100644
--- a/libstdc++-v3/testsuite/experimental/filesystem/operations/copy.cc
+++ b/libstdc++-v3/testsuite/experimental/filesystem/operations/copy.cc
@@ -190,6 +190,34 @@ test05()
   VERIFY( !ec );  // Previous value should be cleared (LWG 2683)
 }
 
+void
+test_pr99290()
+{
+  auto dir = __gnu_test::nonexistent_path();
+  auto source = dir/"source";
+  auto dest = dir/"dest";
+  create_directories(source/"emptydir");
+  create_directories(dest/"emptydir");
+  std::ofstream{source/"file"} << 'a';
+  std::ofstream{dest/"file"} << 'b';
+  // PR libstdc++/99290
+  // std::filesystem::copy does not always report errors for recursion
+  std::error_code ec;
+  copy(source, dest, ec);
+  VERIFY( ec == std::errc::file_exists );
+
+#if __cpp_exceptions
+  try {
+    copy(source, dest);
+    VERIFY( false );
+  } catch (const fs::filesystem_error& e) {
+    VERIFY( e.code() == std::errc::file_exists );
+  }
+#endif
+
+  remove_all(dir);
+}
+
 int
 main()
 {
@@ -198,4 +226,5 @@ main()
   test03();
   test04();
   test05();
+  test_pr99290();
 }