1 files changed, 154 insertions, 0 deletions
diff --git a/components/net/data_loader.rs b/components/net/data_loader.rs
new file mode 100644
index 00000000000..5d9fb776674
--- /dev/null
+++ b/components/net/data_loader.rs
@@ -0,0 +1,154 @@
+/* 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/. */
+
+use std::str;
+
+use resource_task::{Done, Payload, Metadata, LoadData, LoadResponse, LoaderTask, start_sending};
+
+use serialize::base64::FromBase64;
+
+use http::headers::test_utils::from_stream_with_str;
+use http::headers::content_type::MediaType;
+use url::{percent_decode, NonRelativeSchemeData};
+
+
+pub fn factory() -> LoaderTask {
+    proc(url, start_chan) {
+        // NB: we don't spawn a new task.
+        // Hypothesis: data URLs are too small for parallel base64 etc. to be worth it.
+        // Should be tested at some point.
+        load(url, start_chan)
+    }
+}
+
+fn load(load_data: LoadData, start_chan: Sender<LoadResponse>) {
+    let url = load_data.url;
+    assert!("data" == url.scheme.as_slice());
+
+    let mut metadata = Metadata::default(url.clone());
+
+    // Split out content type and data.
+    let mut scheme_data = match url.scheme_data {
+        NonRelativeSchemeData(scheme_data) => scheme_data,
+        _ => fail!("Expected a non-relative scheme URL.")
+    };
+    match url.query {
+        Some(query) => {
+            scheme_data.push_str("?");
+            scheme_data.push_str(query.as_slice());
+        },
+        None => ()
+    }
+    let parts: Vec<&str> = scheme_data.as_slice().splitn(',', 1).collect();
+    if parts.len() != 2 {
+        start_sending(start_chan, metadata).send(Done(Err("invalid data uri".to_string())));
+        return;
+    }
+
+    // ";base64" must come at the end of the content type, per RFC 2397.
+    // rust-http will fail to parse it because there's no =value part.
+    let mut is_base64 = false;
+    let mut ct_str = parts[0];
+    if ct_str.ends_with(";base64") {
+        is_base64 = true;
+        ct_str = ct_str.slice_to(ct_str.as_bytes().len() - 7);
+    }
+
+    // Parse the content type using rust-http.
+    // FIXME: this can go into an infinite loop! (rust-http #25)
+    let content_type: Option<MediaType> = from_stream_with_str(ct_str);
+    metadata.set_content_type(&content_type);
+
+    let progress_chan = start_sending(start_chan, metadata);
+    let bytes = percent_decode(parts[1].as_bytes());
+
+    if is_base64 {
+        // FIXME(#2909): It’s unclear what to do with non-alphabet characters,
+        // but Acid 3 apparently depends on spaces being ignored.
+        let bytes = bytes.move_iter().filter(|&b| b != ' ' as u8).collect::<Vec<u8>>();
+        // FIXME(#2877): use bytes.as_slice().from_base64() when we upgrade to a Rust version
+        // that includes https://github.com/rust-lang/rust/pull/15810
+        let fake_utf8 = unsafe { str::raw::from_utf8(bytes.as_slice()) };
+        match fake_utf8.from_base64() {
+            Err(..) => {
+                progress_chan.send(Done(Err("non-base64 data uri".to_string())));
+            }
+            Ok(data) => {
+                progress_chan.send(Payload(data));
+                progress_chan.send(Done(Ok(())));
+            }
+        }
+    } else {
+        progress_chan.send(Payload(bytes));
+        progress_chan.send(Done(Ok(())));
+    }
+}
+
+#[cfg(test)]
+fn assert_parse(url:          &'static str,
+                content_type: Option<(String, String)>,
+                charset:      Option<String>,
+                data:         Option<Vec<u8>>) {
+    use std::comm;
+    use url::Url;
+
+    let (start_chan, start_port) = comm::channel();
+    load(LoadData::new(Url::parse(url).unwrap()), start_chan);
+
+    let response = start_port.recv();
+    assert_eq!(&response.metadata.content_type, &content_type);
+    assert_eq!(&response.metadata.charset,      &charset);
+
+    let progress = response.progress_port.recv();
+
+    match data {
+        None => {
+            assert_eq!(progress, Done(Err("invalid data uri".to_string())));
+        }
+        Some(dat) => {
+            assert_eq!(progress, Payload(dat));
+            assert_eq!(response.progress_port.recv(), Done(Ok(())));
+        }
+    }
+}
+
+#[test]
+fn empty_invalid() {
+    assert_parse("data:", None, None, None);
+}
+
+#[test]
+fn plain() {
+    assert_parse("data:,hello%20world", None, None, Some(b"hello world".iter().map(|&x| x).collect()));
+}
+
+#[test]
+fn plain_ct() {
+    assert_parse("data:text/plain,hello",
+        Some(("text".to_string(), "plain".to_string())), None, Some(b"hello".iter().map(|&x| x).collect()));
+}
+
+#[test]
+fn plain_charset() {
+    assert_parse("data:text/plain;charset=latin1,hello",
+        Some(("text".to_string(), "plain".to_string())), Some("latin1".to_string()), Some(b"hello".iter().map(|&x| x).collect()));
+}
+
+#[test]
+fn base64() {
+    assert_parse("data:;base64,C62+7w==", None, None, Some(vec!(0x0B, 0xAD, 0xBE, 0xEF)));
+}
+
+#[test]
+fn base64_ct() {
+    assert_parse("data:application/octet-stream;base64,C62+7w==",
+        Some(("application".to_string(), "octet-stream".to_string())), None, Some(vec!(0x0B, 0xAD, 0xBE, 0xEF)));
+}
+
+#[test]
+fn base64_charset() {
+    assert_parse("data:text/plain;charset=koi8-r;base64,8PLl9+XkIO3l5Pfl5A==",
+        Some(("text".to_string(), "plain".to_string())), Some("koi8-r".to_string()),
+        Some(vec!(0xF0, 0xF2, 0xE5, 0xF7, 0xE5, 0xE4, 0x20, 0xED, 0xE5, 0xE4, 0xF7, 0xE5, 0xE4)));
+}