As https://github.com/opscode/chef/issues/2580 summarizes, Link resource need to support relative paths in its 'to' attribute since one can create a symlink pointing to a relative location. This is useful if the directory that symlink resides in moves to a different place (e.g. mounting a disk on a separate location).sersut/revert-1901

This commit preserves relative paths inside the "encode_path" method used by the link operations and expands relative paths in similar fashion when being used by file operations.

2 files changed, 17 insertions, 7 deletions

diff --git a/lib/chef/win32/api/file.rb b/lib/chef/win32/api/file.rb
index 7a8dafd8b5..86b2b942c2 100644
--- a/lib/chef/win32/api/file.rb
+++ b/lib/chef/win32/api/file.rb
@@ -457,11 +457,21 @@ BOOL WINAPI DeviceIoControl(
         # takes the given path pre-pends "\\?\" and
         # UTF-16LE encodes it.  Used to prepare paths
         # to be passed to the *W vesion of WinAPI File
-        # functions
+        # functions.
+        # This function is used by the "Link" resources where we need
+        # preserve relative paths because symbolic links can actually
+        # point to a relative path (relative to the link itself).
         def encode_path(path)
           (path_prepender << path.gsub(::File::SEPARATOR, ::File::ALT_SEPARATOR)).to_wstring
         end
 
+        # Expands the path, prepends "\\?\" and UTF-16LE encodes it.
+        # This function is used by the "File" resources where we need
+        # convert relative paths to fully qualified paths.
+        def canonical_encode_path(path)
+          Chef::Util::PathHelper.canonical_path(path).to_wstring
+        end
+
         def path_prepender
           "\\\\?\\"
         end
@@ -478,7 +488,7 @@ BOOL WINAPI DeviceIoControl(
             # broader fix to map all the paths starting with "/" to
             # SYSTEM_DRIVE on windows.
             path = ::File.expand_path(path) if path.start_with? "/"
-            path = encode_path(path)
+            path = canonical_encode_path(path)
             find_data = WIN32_FIND_DATA.new
             handle = FindFirstFileW(path, find_data)
             if handle == INVALID_HANDLE_VALUE
@@ -495,7 +505,7 @@ BOOL WINAPI DeviceIoControl(
         # ensures the handle is closed on exit of the block
         def file_handle(path, &block)
           begin
-            path = encode_path(path)
+            path = canonical_encode_path(path)
             handle = CreateFileW(path, GENERIC_READ, FILE_SHARE_READ,
                                   nil, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_BACKUP_SEMANTICS, nil)
 
diff --git a/spec/functional/resource/link_spec.rb b/spec/functional/resource/link_spec.rb
index 209002b400..d39a0c2ef6 100644
--- a/spec/functional/resource/link_spec.rb
+++ b/spec/functional/resource/link_spec.rb
@@ -393,7 +393,7 @@ describe Chef::Resource::Link do
             File.open(@other_target, "w") { |file| file.write("eek") }
             symlink(@other_target, to)
             expect(symlink?(to)).to be_truthy
-            expect(readlink(target_file)).to eq(canonicalize(@other_target))
+            expect(readlink(to)).to eq(canonicalize(@other_target))
           end
           after(:each) do
             File.delete(@other_target)
@@ -408,7 +408,7 @@ describe Chef::Resource::Link do
             @other_target = File.join(test_file_dir, make_tmpname("other_spec"))
             symlink(@other_target, to)
             expect(symlink?(to)).to be_truthy
-            expect(readlink(target_file)).to eq(canonicalize(@other_target))
+            expect(readlink(to)).to eq(canonicalize(@other_target))
           end
           context 'and the link does not yet exist' do
             include_context 'create symbolic link succeeds'
@@ -552,7 +552,7 @@ describe Chef::Resource::Link do
             File.open(@other_target, "w") { |file| file.write("eek") }
             symlink(@other_target, to)
             expect(symlink?(to)).to be_truthy
-            expect(readlink(target_file)).to eq(canonicalize(@other_target))
+            expect(readlink(to)).to eq(canonicalize(@other_target))
           end
           after(:each) do
             File.delete(@other_target)
@@ -574,7 +574,7 @@ describe Chef::Resource::Link do
             @other_target = File.join(test_file_dir, make_tmpname("other_spec"))
             symlink(@other_target, to)
             expect(symlink?(to)).to be_truthy
-            expect(readlink(target_file)).to eq(canonicalize(@other_target))
+            expect(readlink(to)).to eq(canonicalize(@other_target))
           end
           context 'and the link does not yet exist' do
             it 'links to the target file' do