Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 64 insertions, 0 deletions

diff --git a/third_party/rust/cssparser/src/from_bytes.rs b/third_party/rust/cssparser/src/from_bytes.rs
new file mode 100644
index 0000000000..78a56d3e14
--- /dev/null
+++ b/third_party/rust/cssparser/src/from_bytes.rs
@@ -0,0 +1,64 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+/// Abstraction for avoiding a dependency from cssparser to an encoding library
+pub trait EncodingSupport {
+    /// One character encoding
+    type Encoding;
+
+    /// https://encoding.spec.whatwg.org/#concept-encoding-get
+    fn from_label(ascii_label: &[u8]) -> Option<Self::Encoding>;
+
+    /// Return the UTF-8 encoding
+    fn utf8() -> Self::Encoding;
+
+    /// Whether the given encoding is UTF-16BE or UTF-16LE
+    fn is_utf16_be_or_le(encoding: &Self::Encoding) -> bool;
+}
+
+/// Determine the character encoding of a CSS stylesheet.
+///
+/// This is based on the presence of a BOM (Byte Order Mark), an `@charset` rule, and
+/// encoding meta-information.
+///
+/// * `css_bytes`: A byte string.
+/// * `protocol_encoding`: The encoding label, if any, defined by HTTP or equivalent protocol.
+///     (e.g. via the `charset` parameter of the `Content-Type` header.)
+/// * `environment_encoding`: An optional `Encoding` object for the [environment encoding]
+///     (https://drafts.csswg.org/css-syntax/#environment-encoding), if any.
+///
+/// Returns the encoding to use.
+pub fn stylesheet_encoding<E>(
+    css: &[u8],
+    protocol_encoding_label: Option<&[u8]>,
+    environment_encoding: Option<E::Encoding>,
+) -> E::Encoding
+where
+    E: EncodingSupport,
+{
+    // https://drafts.csswg.org/css-syntax/#the-input-byte-stream
+    if let Some(label) = protocol_encoding_label {
+        if let Some(protocol_encoding) = E::from_label(label) {
+            return protocol_encoding;
+        };
+    };
+
+    let prefix = b"@charset \"";
+    if css.starts_with(prefix) {
+        let rest = &css[prefix.len()..];
+        if let Some(label_length) = rest.iter().position(|&b| b == b'"') {
+            if rest[label_length..].starts_with(b"\";") {
+                let label = &rest[..label_length];
+                if let Some(charset_encoding) = E::from_label(label) {
+                    if E::is_utf16_be_or_le(&charset_encoding) {
+                        return E::utf8();
+                    } else {
+                        return charset_encoding;
+                    }
+                }
+            }
+        }
+    }
+    environment_encoding.unwrap_or_else(E::utf8)
+}