1 files changed, 135 insertions, 0 deletions
diff --git a/vendor/http-auth/src/table.rs b/vendor/http-auth/src/table.rs
new file mode 100644
index 000000000..64a05d8b4
--- /dev/null
+++ b/vendor/http-auth/src/table.rs
@@ -0,0 +1,135 @@
+// Copyright (C) 2021 Scott Lamb <slamb@slamb.org>
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+//! Builds and offers lookup on a table of byte values to the character
+//! classes the respective bytes are part of. Most classes are referenced from
+//! [RFC 7235 Appendix B: Imported ABNF](https://datatracker.ietf.org/doc/html/rfc7235#appendix-B)
+//! or [RFC 7235 Appendix C: Collected ABNF](https://datatracker.ietf.org/doc/html/rfc7235#appendix-C).
+
+pub(crate) const C_TCHAR: u8 = 1;
+pub(crate) const C_QDTEXT: u8 = 2;
+pub(crate) const C_ESCAPABLE: u8 = 4;
+pub(crate) const C_OWS: u8 = 8;
+pub(crate) const C_ATTR: u8 = 16;
+
+static TABLE: [u8; 128] = build_table();
+
+pub(crate) fn char_classes(b: u8) -> u8 {
+    *TABLE.get(usize::from(b)).unwrap_or(&0)
+}
+
+const fn build_table() -> [u8; 128] {
+    // It'd be nice to use array::from_fn here, but it wasn't stablized until Rust 1.63.
+    let mut table = [0u8; 128];
+    let mut i = 0;
+    while i < 128 {
+        let b = i as u8;
+        let mut classes = 0;
+        if is_tchar(b) {
+            classes |= C_TCHAR;
+        }
+        if is_qdtext(b) {
+            classes |= C_QDTEXT;
+        }
+        if is_escapable(b) {
+            classes |= C_ESCAPABLE;
+        }
+        if is_ows(b) {
+            classes |= C_OWS;
+        }
+        if is_attr(b) {
+            classes |= C_ATTR;
+        }
+        table[i] = classes;
+        i += 1;
+    }
+    table
+}
+
+/// Returns if the byte is a `tchar` as defined in
+/// [RFC 7230 section 3.2.6](https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.6).
+const fn is_tchar(b: u8) -> bool {
+    // tchar          = "!" / "#" / "$" / "%" / "&" / "'" / "*"
+    //                / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
+    //                / DIGIT / ALPHA
+    //                ; any VCHAR, except delimiters
+    matches!(b,
+        b'!'
+        | b'#'
+        | b'$'
+        | b'%'
+        | b'&'
+        | b'\''
+        | b'*'
+        | b'+'
+        | b'-'
+        | b'.'
+        | b'^'
+        | b'_'
+        | b'`'
+        | b'|'
+        | b'~'
+        | b'0'..=b'9'
+        | b'a'..=b'z'
+        | b'A'..=b'Z')
+}
+
+/// Returns true if the byte is a valid `qdtext` (excluding `obs-text`), as defined in
+/// [RFC 7230 section 3.2.6](https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.6).
+///
+/// ```text
+/// quoted-string  = DQUOTE *( qdtext / quoted-pair ) DQUOTE
+/// qdtext         = HTAB / SP /%x21 / %x23-5B / %x5D-7E / obs-text
+/// obs-text       = %x80-FF
+/// quoted-pair    = "\" ( HTAB / SP / VCHAR / obs-text )
+/// VCHAR          =  %x21-7E
+///                ; visible (printing) characters
+/// ```
+const fn is_qdtext(b: u8) -> bool {
+    matches!(b, b'\t' | b' ' | 0x21 | 0x23..=0x5B | 0x5D..=0x7E)
+}
+
+/// Returns true if the byte is a valid end of a `quoted-pair`, as defined in
+/// [RFC 7230 section 3.2.6](https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.6).
+const fn is_escapable(b: u8) -> bool {
+    matches!(b, b'\t' | b' ' | 0x21..=0x7E | 0x80..=0xFF)
+}
+
+/// Returns true if the byte is a valid `attr-char` as defined in
+/// [RFC 5987 section 3.2.1](https://datatracker.ietf.org/doc/html/rfc5987#section-3.2.1).
+///
+/// ```text
+///  attr-char     = ALPHA / DIGIT
+///                / "!" / "#" / "$" / "&" / "+" / "-" / "."
+///                / "^" / "_" / "`" / "|" / "~"
+///                ; token except ( "*" / "'" / "%" )
+/// ```
+const fn is_attr(b: u8) -> bool {
+    matches!(b,
+        b'a'..=b'z'
+        | b'A'..=b'Z'
+        | b'0'..=b'9'
+        | b'!'
+        | b'#'
+        | b'$'
+        | b'&'
+        | b'+'
+        | b'-'
+        | b'.'
+        | b'^'
+        | b'_'
+        | b'`'
+        | b'|'
+        | b'~')
+}
+
+/// Returns true if the byte is valid optional whitespace as in [RFC 7230 section
+/// 3.2.3](https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.3).
+///
+/// ```text
+///      OWS            = *( SP / HTAB )
+///                     ; optional whitespace
+/// ```
+const fn is_ows(b: u8) -> bool {
+    matches!(b, b' ' | b'\t')
+}