1 files changed, 105 insertions, 0 deletions
diff --git a/servo/components/style/encoding_support.rs b/servo/components/style/encoding_support.rs
new file mode 100644
index 0000000000..c144ad0b3b
--- /dev/null
+++ b/servo/components/style/encoding_support.rs
@@ -0,0 +1,105 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Parsing stylesheets from bytes (not `&str`).
+
+use crate::context::QuirksMode;
+use crate::error_reporting::ParseErrorReporter;
+use crate::media_queries::MediaList;
+use crate::shared_lock::SharedRwLock;
+use crate::stylesheets::{AllowImportRules, Origin, Stylesheet, StylesheetLoader, UrlExtraData};
+use cssparser::{stylesheet_encoding, EncodingSupport};
+use servo_arc::Arc;
+use std::borrow::Cow;
+use std::str;
+
+struct EncodingRs;
+
+impl EncodingSupport for EncodingRs {
+    type Encoding = &'static encoding_rs::Encoding;
+
+    fn utf8() -> Self::Encoding {
+        encoding_rs::UTF_8
+    }
+
+    fn is_utf16_be_or_le(encoding: &Self::Encoding) -> bool {
+        *encoding == encoding_rs::UTF_16LE || *encoding == encoding_rs::UTF_16BE
+    }
+
+    fn from_label(ascii_label: &[u8]) -> Option<Self::Encoding> {
+        encoding_rs::Encoding::for_label(ascii_label)
+    }
+}
+
+fn decode_stylesheet_bytes<'a>(
+    css: &'a [u8],
+    protocol_encoding_label: Option<&str>,
+    environment_encoding: Option<&'static encoding_rs::Encoding>,
+) -> Cow<'a, str> {
+    let fallback_encoding = stylesheet_encoding::<EncodingRs>(
+        css,
+        protocol_encoding_label.map(str::as_bytes),
+        environment_encoding,
+    );
+    let (result, _used_encoding, _) = fallback_encoding.decode(&css);
+    // FIXME record used encoding for environment encoding of @import
+    result
+}
+
+impl Stylesheet {
+    /// Parse a stylesheet from a set of bytes, potentially received over the
+    /// network.
+    ///
+    /// Takes care of decoding the network bytes and forwards the resulting
+    /// string to `Stylesheet::from_str`.
+    pub fn from_bytes(
+        bytes: &[u8],
+        url_data: UrlExtraData,
+        protocol_encoding_label: Option<&str>,
+        environment_encoding: Option<&'static encoding_rs::Encoding>,
+        origin: Origin,
+        media: MediaList,
+        shared_lock: SharedRwLock,
+        stylesheet_loader: Option<&dyn StylesheetLoader>,
+        error_reporter: Option<&dyn ParseErrorReporter>,
+        quirks_mode: QuirksMode,
+    ) -> Stylesheet {
+        let string = decode_stylesheet_bytes(bytes, protocol_encoding_label, environment_encoding);
+        Stylesheet::from_str(
+            &string,
+            url_data,
+            origin,
+            Arc::new(shared_lock.wrap(media)),
+            shared_lock,
+            stylesheet_loader,
+            error_reporter,
+            quirks_mode,
+            0,
+            AllowImportRules::Yes,
+        )
+    }
+
+    /// Updates an empty stylesheet with a set of bytes that reached over the
+    /// network.
+    pub fn update_from_bytes(
+        existing: &Stylesheet,
+        bytes: &[u8],
+        protocol_encoding_label: Option<&str>,
+        environment_encoding: Option<&'static encoding_rs::Encoding>,
+        url_data: UrlExtraData,
+        stylesheet_loader: Option<&dyn StylesheetLoader>,
+        error_reporter: Option<&dyn ParseErrorReporter>,
+    ) {
+        let string = decode_stylesheet_bytes(bytes, protocol_encoding_label, environment_encoding);
+        Self::update_from_str(
+            existing,
+            &string,
+            url_data,
+            stylesheet_loader,
+            error_reporter,
+            0,
+            AllowImportRules::Yes,
+        )
+    }
+}