Win32: Improve restoring of special attributes

[wimlib] / src / win32.c

diff --git a/src/win32.c b/src/win32.c
index 638380908b62091fe7b91dbb164adbecb152271d..05f457a87df3e28c9e692b2d35f2ae266d5ec5d4 100644 (file)
--- a/src/win32.c
+++ b/src/win32.c
@@ -1029,6 +1029,41 @@ win32_set_reparse_data(HANDLE h,
        return 0;
 }
 
+static int
+win32_set_compressed(HANDLE hFile, const wchar_t *path)
+{
+       USHORT format = COMPRESSION_FORMAT_DEFAULT;
+       DWORD bytesReturned = 0;
+       if (!DeviceIoControl(hFile, FSCTL_SET_COMPRESSION,
+                            &format, sizeof(USHORT),
+                            NULL, 0,
+                            &bytesReturned, NULL))
+       {
+               /* Warning only */
+               DWORD err = GetLastError();
+               WARNING("Failed to set compression flag on \"%ls\"", path);
+               win32_error(err);
+       }
+       return 0;
+}
+
+static int
+win32_set_sparse(HANDLE hFile, const wchar_t *path)
+{
+       DWORD bytesReturned = 0;
+       if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE,
+                            NULL, 0,
+                            NULL, 0,
+                            &bytesReturned, NULL))
+       {
+               /* Warning only */
+               DWORD err = GetLastError();
+               WARNING("Failed to set sparse flag on \"%ls\"", path);
+               win32_error(err);
+       }
+       return 0;
+}
+
 /*
  * Sets the security descriptor on an extracted file.
  */
@@ -1145,6 +1180,91 @@ path_is_root_of_drive(const wchar_t *path)
        return (*path == L'\0');
 }
 
+static DWORD
+win32_get_create_flags_and_attributes(DWORD i_attributes)
+{
+       DWORD attributes;
+
+       /*
+        * Some attributes cannot be set by passing them to CreateFile().  In
+        * particular:
+        *
+        * FILE_ATTRIBUTE_DIRECTORY:
+        *   CreateDirectory() must be called instead of CreateFile().
+        *
+        * FILE_ATTRIBUTE_SPARSE_FILE:
+        *   Needs an ioctl.
+        *   See: win32_set_sparse().
+        *
+        * FILE_ATTRIBUTE_COMPRESSED:
+        *   Not clear from the documentation, but apparently this needs an
+        *   ioctl as well.
+        *   See: win32_set_compressed().
+        *
+        * FILE_ATTRIBUTE_REPARSE_POINT:
+        *   Needs an ioctl, with the reparse data specified.
+        *   See: win32_set_reparse_data().
+        *
+        * In addition, clear any file flags in the attributes that we don't
+        * want, but also specify FILE_FLAG_OPEN_REPARSE_POINT and
+        * FILE_FLAG_BACKUP_SEMANTICS as we are a backup application.
+        */
+       attributes = i_attributes & ~(FILE_ATTRIBUTE_SPARSE_FILE |
+                                     FILE_ATTRIBUTE_COMPRESSED |
+                                     FILE_ATTRIBUTE_REPARSE_POINT |
+                                     FILE_ATTRIBUTE_DIRECTORY |
+                                     FILE_FLAG_DELETE_ON_CLOSE |
+                                     FILE_FLAG_NO_BUFFERING |
+                                     FILE_FLAG_OPEN_NO_RECALL |
+                                     FILE_FLAG_OVERLAPPED |
+                                     FILE_FLAG_RANDOM_ACCESS |
+                                     /*FILE_FLAG_SESSION_AWARE |*/
+                                     FILE_FLAG_SEQUENTIAL_SCAN |
+                                     FILE_FLAG_WRITE_THROUGH);
+       return attributes |
+              FILE_FLAG_OPEN_REPARSE_POINT |
+              FILE_FLAG_BACKUP_SEMANTICS;
+}
+
+static bool
+inode_has_special_attributes(const struct wim_inode *inode)
+{
+       return (inode->i_attributes & (FILE_ATTRIBUTE_COMPRESSED |
+                                      FILE_ATTRIBUTE_REPARSE_POINT |
+                                      FILE_ATTRIBUTE_SPARSE_FILE)) != 0;
+}
+
+static int
+win32_set_special_attributes(HANDLE hFile, const struct wim_inode *inode,
+                            struct wim_lookup_table_entry *unnamed_stream_lte,
+                            const wchar_t *path)
+{
+       int ret;
+
+       if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
+               DEBUG("Setting reparse data on \"%ls\"", path);
+               ret = win32_set_reparse_data(hFile, inode->i_reparse_tag,
+                                            unnamed_stream_lte, path);
+               if (ret)
+                       return ret;
+       }
+
+       if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED) {
+               DEBUG("Setting compression flag on \"%ls\"", path);
+               ret = win32_set_compressed(hFile, path);
+               if (ret)
+                       return ret;
+       }
+
+       if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE) {
+               DEBUG("Setting sparse flag on \"%ls\"", path);
+               ret = win32_set_sparse(hFile, path);
+               if (ret)
+                       return ret;
+       }
+       return 0;
+}
+
 static int
 win32_extract_stream(const struct wim_inode *inode,
                     const wchar_t *path,
@@ -1213,7 +1333,7 @@ win32_extract_stream(const struct wim_inode *inode,
                                }
                        }
                        DEBUG("Created directory \"%ls\"", stream_path);
-                       if (!(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
+                       if (!inode_has_special_attributes(inode)) {
                                ret = 0;
                                goto out;
                        }
@@ -1223,13 +1343,11 @@ win32_extract_stream(const struct wim_inode *inode,
 
        DEBUG("Opening \"%ls\"", stream_path);
        h = CreateFileW(stream_path,
-                       GENERIC_WRITE,
+                       GENERIC_READ | GENERIC_WRITE,
                        0,
                        NULL,
                        creationDisposition,
-                       FILE_FLAG_OPEN_REPARSE_POINT |
-                           FILE_FLAG_BACKUP_SEMANTICS |
-                           inode->i_attributes,
+                       win32_get_create_flags_and_attributes(inode->i_attributes),
                        NULL);
        if (h == INVALID_HANDLE_VALUE) {
                err = GetLastError();
@@ -1239,14 +1357,13 @@ win32_extract_stream(const struct wim_inode *inode,
                goto fail;
        }
 
-       if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT &&
-           stream_name_utf16 == NULL)
-       {
-               DEBUG("Setting reparse data on \"%ls\"", path);
-               ret = win32_set_reparse_data(h, inode->i_reparse_tag, lte, path);
+       if (stream_name_utf16 == NULL && inode_has_special_attributes(inode)) {
+               ret = win32_set_special_attributes(h, inode, lte, path);
                if (ret)
                        goto fail_close_handle;
-       } else {
+       }
+
+       if (!(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
                if (lte) {
                        DEBUG("Extracting \"%ls\" (len = %"PRIu64")",
                              stream_path, wim_resource_size(lte));