use HttpTryFrom;
use byte_str::ByteStr;
use bytes::{Bytes, BytesMut};
use std::{fmt, mem};
use std::borrow::Borrow;
use std::hash::{Hash, Hasher};
use std::str::FromStr;
use std::error::Error;
/// Represents an HTTP header field name
///
/// Header field names identify the header. Header sets may include multiple
/// headers with the same name. The HTTP specification defines a number of
/// standard headers, but HTTP messages may include non-standard header names as
/// well as long as they adhere to the specification.
///
/// `HeaderName` is used as the [`HeaderMap`] key. Constants are available for
/// all standard header names in the [`header`] module.
///
/// # Representation
///
/// `HeaderName` represents standard header names using an `enum`, as such they
/// will not require an allocation for storage. All custom header names are
/// lower cased upon conversion to a `HeaderName` value. This avoids the
/// overhead of dynamically doing lower case conversion during the hash code
/// computation and the comparison operation.
///
/// [`HeaderMap`]: struct.HeaderMap.html
/// [`header`]: index.html
#[derive(Clone, Eq, PartialEq, Hash)]
pub struct HeaderName {
inner: Repr<Custom>,
}
// Almost a full `HeaderName`
#[derive(Debug, Hash)]
pub struct HdrName<'a> {
inner: Repr<MaybeLower<'a>>,
}
#[derive(Debug, Clone, Eq, PartialEq, Hash)]
enum Repr<T> {
Standard(StandardHeader),
Custom(T),
}
// Used to hijack the Hash impl
#[derive(Debug, Clone, Eq, PartialEq)]
struct Custom(ByteStr);
#[derive(Debug, Clone)]
struct MaybeLower<'a> {
buf: &'a [u8],
lower: bool,
}
/// A possible error when converting a `HeaderName` from another type.
#[derive(Debug)]
pub struct InvalidHeaderName {
_priv: (),
}
/// A possible error when converting a `HeaderName` from another type.
#[derive(Debug)]
pub struct InvalidHeaderNameBytes(InvalidHeaderName) ;
macro_rules! standard_headers {
(
$(
$(#[$docs:meta])*
($konst:ident, $upcase:ident, $name:expr);
)+
) => {
#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
enum StandardHeader {
$(
$konst,
)+
}
$(
$(#[$docs])*
pub const $upcase: HeaderName = HeaderName {
inner: Repr::Standard(StandardHeader::$konst),
};
)+
impl StandardHeader {
#[inline]
fn as_str(&self) -> &'static str {
match *self {
$(
StandardHeader::$konst => $name,
)+
}
}
}
#[cfg(test)]
const TEST_HEADERS: &'static [(StandardHeader, &'static str)] = &[
$(
(StandardHeader::$konst, $name),
)+
];
#[test]
fn test_parse_standard_headers() {
for &(std, name) in TEST_HEADERS {
// Test lower case
assert_eq!(HeaderName::from_bytes(name.as_bytes()).unwrap(), HeaderName::from(std));
// Test upper case
let upper = name.to_uppercase().to_string();
assert_eq!(HeaderName::from_bytes(upper.as_bytes()).unwrap(), HeaderName::from(std));
}
}
#[test]
fn test_standard_headers_into_bytes() {
for &(std, name) in TEST_HEADERS {
let std = HeaderName::from(std);
// Test lower case
let name_bytes = name.as_bytes();
let bytes: Bytes =
HeaderName::from_bytes(name_bytes).unwrap().into();
assert_eq!(bytes, name_bytes);
assert_eq!(HeaderName::try_from(Bytes::from(name_bytes)).unwrap(), std);
// Test upper case
let upper = name.to_uppercase().to_string();
let bytes: Bytes =
HeaderName::from_bytes(upper.as_bytes()).unwrap().into();
assert_eq!(bytes, name.as_bytes());
assert_eq!(HeaderName::try_from(Bytes::from(upper.as_bytes())).unwrap(),
std);
}
}
}
}
// Generate constants for all standard HTTP headers. This includes a static hash
// code for the "fast hash" path. The hash code for static headers *do not* have
// to match the text representation of those headers. This is because header
// strings are always converted to the static values (when they match) before
// being hashed. This means that it is impossible to compare the static hash
// code of CONTENT_LENGTH with "content-length".
standard_headers! {
/// Advertises which content types the client is able to understand.
///
/// The Accept request HTTP header advertises which content types, expressed
/// as MIME types, the client is able to understand. Using content
/// negotiation, the server then selects one of the proposals, uses it and
/// informs the client of its choice with the Content-Type response header.
/// Browsers set adequate values for this header depending of the context
/// where the request is done: when fetching a CSS stylesheet a different
/// value is set for the request than when fetching an image, video or a
/// script.
(Accept, ACCEPT, "accept");
/// Advertises which character set the client is able to understand.
///
/// The Accept-Charset request HTTP header advertises which character set
/// the client is able to understand. Using content negotiation, the server
/// then selects one of the proposals, uses it and informs the client of its
/// choice within the Content-Type response header. Browsers usually don't
/// set this header as the default value for each content type is usually
/// correct and transmitting it would allow easier fingerprinting.
///
/// If the server cannot serve any matching character set, it can
/// theoretically send back a 406 (Not Acceptable) error code. But, for a
/// better user experience, this is rarely done and the more common way is
/// to ignore the Accept-Charset header in this case.
(AcceptCharset, ACCEPT_CHARSET, "accept-charset");
/// Advertises which content encoding the client is able to understand.
///
/// The Accept-Encoding request HTTP header advertises which content
/// encoding, usually a compression algorithm, the client is able to
/// understand. Using content negotiation, the server selects one of the
/// proposals, uses it and informs the client of its choice with the
/// Content-Encoding response header.
///
/// Even if both the client and the server supports the same compression
/// algorithms, the server may choose not to compress the body of a
/// response, if the identity value is also acceptable. Two common cases
/// lead to this:
///
/// * The data to be sent is already compressed and a second compression
/// won't lead to smaller data to be transmitted. This may the case with
/// some image formats;
///
/// * The server is overloaded and cannot afford the computational overhead
/// induced by the compression requirement. Typically, Microsoft recommends
/// not to compress if a server use more than 80 % of its computational
/// power.
///
/// As long as the identity value, meaning no encryption, is not explicitly
/// forbidden, by an identity;q=0 or a *;q=0 without another explicitly set
/// value for identity, the server must never send back a 406 Not Acceptable
/// error.
(AcceptEncoding, ACCEPT_ENCODING, "accept-encoding");
/// Advertises which languages the client is able to understand.
///
/// The Accept-Language request HTTP header advertises which languages the
/// client is able to understand, and which locale variant is preferred.
/// Using content negotiation, the server then selects one of the proposals,
/// uses it and informs the client of its choice with the Content-Language
/// response header. Browsers set adequate values for this header according
/// their user interface language and even if a user can change it, this
/// happens rarely (and is frown upon as it leads to fingerprinting).
///
/// This header is a hint to be used when the server has no way of
/// determining the language via another way, like a specific URL, that is
/// controlled by an explicit user decision. It is recommended that the
/// server never overrides an explicit decision. The content of the
/// Accept-Language is often out of the control of the user (like when
/// traveling and using an Internet Cafe in a different country); the user
/// may also want to visit a page in another language than the locale of
/// their user interface.
///
/// If the server cannot serve any matching language, it can theoretically
/// send back a 406 (Not Acceptable) error code. But, for a better user
/// experience, this is rarely done and more common way is to ignore the
/// Accept-Language header in this case.
(AcceptLanguage, ACCEPT_LANGUAGE, "accept-language");
/// Marker used by the server to advertise partial request support.
///
/// The Accept-Ranges response HTTP header is a marker used by the server to
/// advertise its support of partial requests. The value of this field
/// indicates the unit that can be used to define a range.
///
/// In presence of an Accept-Ranges header, the browser may try to resume an
/// interrupted download, rather than to start it from the start again.
(AcceptRanges, ACCEPT_RANGES, "accept-ranges");
/// Preflight response indicating if the response to the request can be
/// exposed to the page.
///
/// The Access-Control-Allow-Credentials response header indicates whether
/// or not the response to the request can be exposed to the page. It can be
/// exposed when the true value is returned; it can't in other cases.
///
/// Credentials are cookies, authorization headers or TLS client
/// certificates.
///
/// When used as part of a response to a preflight request, this indicates
/// whether or not the actual request can be made using credentials. Note
/// that simple GET requests are not preflighted, and so if a request is
/// made for a resource with credentials, if this header is not returned
/// with the resource, the response is ignored by the browser and not
/// returned to web content.
///
/// The Access-Control-Allow-Credentials header works in conjunction with
/// the XMLHttpRequest.withCredentials property or with the credentials
/// option in the Request() constructor of the Fetch API. Credentials must
/// be set on both sides (the Access-Control-Allow-Credentials header and in
/// the XHR or Fetch request) in order for the CORS request with credentials
/// to succeed.
(AccessControlAllowCredentials, ACCESS_CONTROL_ALLOW_CREDENTIALS, "access-control-allow-credentials");
/// Preflight response indicating permitted HTTP headers.
///
/// The Access-Control-Allow-Headers response header is used in response to
/// a preflight request to indicate which HTTP headers will be available via
/// Access-Control-Expose-Headers when making the actual request.
///
/// The simple headers, Accept, Accept-Language, Content-Language,
/// Content-Type (but only with a MIME type of its parsed value (ignoring
/// parameters) of either application/x-www-form-urlencoded,
/// multipart/form-data, or text/plain), are always available and don't need
/// to be listed by this header.
///
/// This header is required if the request has an
/// Access-Control-Request-Headers header.
(AccessControlAllowHeaders, ACCESS_CONTROL_ALLOW_HEADERS, "access-control-allow-headers");
/// Preflight header response indicating permitted access methods.
///
/// The Access-Control-Allow-Methods response header specifies the method or
/// methods allowed when accessing the resource in response to a preflight
/// request.
(AccessControlAllowMethods, ACCESS_CONTROL_ALLOW_METHODS, "access-control-allow-methods");
/// Indicates whether the response can be shared with resources with the
/// given origin.
(AccessControlAllowOrigin, ACCESS_CONTROL_ALLOW_ORIGIN, "access-control-allow-origin");
/// Indicates which headers can be exposed as part of the response by
/// listing their names.
(AccessControlExposeHeaders, ACCESS_CONTROL_EXPOSE_HEADERS, "access-control-expose-headers");
/// Indicates how long the results of a preflight request can be cached.
(AccessControlMaxAge, ACCESS_CONTROL_MAX_AGE, "access-control-max-age");
/// Informs the server which HTTP headers will be used when an actual
/// request is made.
(AccessControlRequestHeaders, ACCESS_CONTROL_REQUEST_HEADERS, "access-control-request-headers");
/// Informs the server know which HTTP method will be used when the actual
/// request is made.
(AccessControlRequestMethod, ACCESS_CONTROL_REQUEST_METHOD, "access-control-request-method");
/// Indicates the time in seconds the object has been in a proxy cache.
///
/// The Age header is usually close to zero. If it is Age: 0, it was
/// probably just fetched from the origin server; otherwise It is usually
/// calculated as a difference between the proxy's current date and the Date
/// general header included in the HTTP response.
(Age, AGE, "age");
/// Lists the set of methods support by a resource.
///
/// This header must be sent if the server responds with a 405 Method Not
/// Allowed status code to indicate which request methods can be used. An
/// empty Allow header indicates that the resource allows no request
/// methods, which might occur temporarily for a given resource, for
/// example.
(Allow, ALLOW, "allow");
/// Advertises the availability of alternate services to clients.
(AltSvc, ALT_SVC, "alt-svc");
/// Contains the credentials to authenticate a user agent with a server.
///
/// Usually this header is included after the server has responded with a
/// 401 Unauthorized status and the WWW-Authenticate header.
(Authorization, AUTHORIZATION, "authorization");
/// Specifies directives for caching mechanisms in both requests and
/// responses.
///
/// Caching directives are unidirectional, meaning that a given directive in
/// a request is not implying that the same directive is to be given in the
/// response.
(CacheControl, CACHE_CONTROL, "cache-control");
/// Controls whether or not the network connection stays open after the
/// current transaction finishes.
///
/// If the value sent is keep-alive, the connection is persistent and not
/// closed, allowing for subsequent requests to the same server to be done.
///
/// Except for the standard hop-by-hop headers (Keep-Alive,
/// Transfer-Encoding, TE, Connection, Trailer, Upgrade, Proxy-Authorization
/// and Proxy-Authenticate), any hop-by-hop headers used by the message must
/// be listed in the Connection header, so that the first proxy knows he has
/// to consume them and not to forward them further. Standard hop-by-hop
/// headers can be listed too (it is often the case of Keep-Alive, but this
/// is not mandatory.
(Connection, CONNECTION, "connection");
/// Indicates if the content is expected to be displayed inline.
///
/// In a regular HTTP response, the Content-Disposition response header is a
/// header indicating if the content is expected to be displayed inline in
/// the browser, that is, as a Web page or as part of a Web page, or as an
/// attachment, that is downloaded and saved locally.
///
/// In a multipart/form-data body, the HTTP Content-Disposition general
/// header is a header that can be used on the subpart of a multipart body
/// to give information about the field it applies to. The subpart is
/// delimited by the boundary defined in the Content-Type header. Used on
/// the body itself, Content-Disposition has no effect.
///
/// The Content-Disposition header is defined in the larger context of MIME
/// messages for e-mail, but only a subset of the possible parameters apply
/// to HTTP forms and POST requests. Only the value form-data, as well as
/// the optional directive name and filename, can be used in the HTTP
/// context.
(ContentDisposition, CONTENT_DISPOSITION, "content-disposition");
/// Used to compress the media-type.
///
/// When present, its value indicates what additional content encoding has
/// been applied to the entity-body. It lets the client know, how to decode
/// in order to obtain the media-type referenced by the Content-Type header.
///
/// It is recommended to compress data as much as possible and therefore to
/// use this field, but some types of resources, like jpeg images, are
/// already compressed. Sometimes using additional compression doesn't
/// reduce payload size and can even make the payload longer.
(ContentEncoding, CONTENT_ENCODING, "content-encoding");
/// Used to describe the languages intended for the audience.
///
/// This header allows a user to differentiate according to the users' own
/// preferred language. For example, if "Content-Language: de-DE" is set, it
/// says that the document is intended for German language speakers
/// (however, it doesn't indicate the document is written in German. For
/// example, it might be written in English as part of a language course for
/// German speakers).
///
/// If no Content-Language is specified, the default is that the content is
/// intended for all language audiences. Multiple language tags are also
/// possible, as well as applying the Content-Language header to various
/// media types and not only to textual documents.
(ContentLanguage, CONTENT_LANGUAGE, "content-language");
/// Indicates the size fo the entity-body.
///
/// The header value must be a decimal indicating the number of octets sent
/// to the recipient.
(ContentLength, CONTENT_LENGTH, "content-length");
/// Indicates an alternate location for the returned data.
///
/// The principal use case is to indicate the URL of the resource
/// transmitted as the result of content negotiation.
///
/// Location and Content-Location are different: Location indicates the
/// target of a redirection (or the URL of a newly created document), while
/// Content-Location indicates the direct URL to use to access the resource,
/// without the need of further content negotiation. Location is a header
/// associated with the response, while Content-Location is associated with
/// the entity returned.
(ContentLocation, CONTENT_LOCATION, "content-location");
/// Indicates where in a full body message a partial message belongs.
(ContentRange, CONTENT_RANGE, "content-range");
/// Allows controlling resources the user agent is allowed to load for a
/// given page.
///
/// With a few exceptions, policies mostly involve specifying server origins
/// and script endpoints. This helps guard against cross-site scripting
/// attacks (XSS).
(ContentSecurityPolicy, CONTENT_SECURITY_POLICY, "content-security-policy");
/// Allows experimenting with policies by monitoring their effects.
///
/// The HTTP Content-Security-Policy-Report-Only response header allows web
/// developers to experiment with policies by monitoring (but not enforcing)
/// their effects. These violation reports consist of JSON documents sent
/// via an HTTP POST request to the specified URI.
(ContentSecurityPolicyReportOnly, CONTENT_SECURITY_POLICY_REPORT_ONLY, "content-security-policy-report-only");
/// Used to indicate the media type of the resource.
///
/// In responses, a Content-Type header tells the client what the content
/// type of the returned content actually is. Browsers will do MIME sniffing
/// in some cases and will not necessarily follow the value of this header;
/// to prevent this behavior, the header X-Content-Type-Options can be set
/// to nosniff.
///
/// In requests, (such as POST or PUT), the client tells the server what
/// type of data is actually sent.
(ContentType, CONTENT_TYPE, "content-type");
/// Contains stored HTTP cookies previously sent by the server with the
/// Set-Cookie header.
///
/// The Cookie header might be omitted entirely, if the privacy setting of
/// the browser are set to block them, for example.
(Cookie, COOKIE, "cookie");
/// Indicates the client's tracking preference.
///
/// This header lets users indicate whether they would prefer privacy rather
/// than personalized content.
(Dnt, DNT, "dnt");
/// Contains the date and time at which the message was originated.
(Date, DATE, "date");
/// Identifier for a specific version of a resource.
///
/// This header allows caches to be more efficient, and saves bandwidth, as
/// a web server does not need to send a full response if the content has
/// not changed. On the other side, if the content has changed, etags are
/// useful to help prevent simultaneous updates of a resource from
/// overwriting each other ("mid-air collisions").
///
/// If the resource at a given URL changes, a new Etag value must be
/// generated. Etags are therefore similar to fingerprints and might also be
/// used for tracking purposes by some servers. A comparison of them allows
/// to quickly determine whether two representations of a resource are the
/// same, but they might also be set to persist indefinitely by a tracking
/// server.
(Etag, ETAG, "etag");
/// Indicates expectations that need to be fulfilled by the server in order
/// to properly handle the request.
///
/// The only expectation defined in the specification is Expect:
/// 100-continue, to which the server shall respond with:
///
/// * 100 if the information contained in the header is sufficient to cause
/// an immediate success,
///
/// * 417 (Expectation Failed) if it cannot meet the expectation; or any
/// other 4xx status otherwise.
///
/// For example, the server may reject a request if its Content-Length is
/// too large.
///
/// No common browsers send the Expect header, but some other clients such
/// as cURL do so by default.
(Expect, EXPECT, "expect");
/// Contains the date/time after which the response is considered stale.
///
/// Invalid dates, like the value 0, represent a date in the past and mean
/// that the resource is already expired.
///
/// If there is a Cache-Control header with the "max-age" or "s-max-age"
/// directive in the response, the Expires header is ignored.
(Expires, EXPIRES, "expires");
/// Contains information from the client-facing side of proxy servers that
/// is altered or lost when a proxy is involved in the path of the request.
///
/// The alternative and de-facto standard versions of this header are the
/// X-Forwarded-For, X-Forwarded-Host and X-Forwarded-Proto headers.
///
/// This header is used for debugging, statistics, and generating
/// location-dependent content and by design it exposes privacy sensitive
/// information, such as the IP address of the client. Therefore the user's
/// privacy must be kept in mind when deploying this header.
(Forwarded, FORWARDED, "forwarded");
/// Contains an Internet email address for a human user who controls the
/// requesting user agent.
///
/// If you are running a robotic user agent (e.g. a crawler), the From
/// header should be sent, so you can be contacted if problems occur on
/// servers, such as if the robot is sending excessive, unwanted, or invalid
/// requests.
(From, FROM, "from");
/// Specifies the domain name of the server and (optionally) the TCP port
/// number on which the server is listening.
///
/// If no port is given, the default port for the service requested (e.g.,
/// "80" for an HTTP URL) is implied.
///
/// A Host header field must be sent in all HTTP/1.1 request messages. A 400
/// (Bad Request) status code will be sent to any HTTP/1.1 request message
/// that lacks a Host header field or contains more than one.
(Host, HOST, "host");
/// Makes a request conditional based on the E-Tag.
///
/// For GET and HEAD methods, the server will send back the requested
/// resource only if it matches one of the listed ETags. For PUT and other
/// non-safe methods, it will only upload the resource in this case.
///
/// The comparison with the stored ETag uses the strong comparison
/// algorithm, meaning two files are considered identical byte to byte only.
/// This is weakened when the W/ prefix is used in front of the ETag.
///
/// There are two common use cases:
///
/// * For GET and HEAD methods, used in combination with an Range header, it
/// can guarantee that the new ranges requested comes from the same resource
/// than the previous one. If it doesn't match, then a 416 (Range Not
/// Satisfiable) response is returned.
///
/// * For other methods, and in particular for PUT, If-Match can be used to
/// prevent the lost update problem. It can check if the modification of a
/// resource that the user wants to upload will not override another change
/// that has been done since the original resource was fetched. If the
/// request cannot be fulfilled, the 412 (Precondition Failed) response is
/// returned.
(IfMatch, IF_MATCH, "if-match");
/// Makes a request conditional based on the modification date.
///
/// The If-Modified-Since request HTTP header makes the request conditional:
/// the server will send back the requested resource, with a 200 status,
/// only if it has been last modified after the given date. If the request
/// has not been modified since, the response will be a 304 without any
/// body; the Last-Modified header will contain the date of last
/// modification. Unlike If-Unmodified-Since, If-Modified-Since can only be
/// used with a GET or HEAD.
///
/// When used in combination with If-None-Match, it is ignored, unless the
/// server doesn't support If-None-Match.
///
/// The most common use case is to update a cached entity that has no
/// associated ETag.
(IfModifiedSince, IF_MODIFIED_SINCE, "if-modified-since");
/// Makes a request conditional based on the E-Tag.
///
/// The If-None-Match HTTP request header makes the request conditional. For
/// GET and HEAD methods, the server will send back the requested resource,
/// with a 200 status, only if it doesn't have an ETag matching the given
/// ones. For other methods, the request will be processed only if the
/// eventually existing resource's ETag doesn't match any of the values
/// listed.
///
/// When the condition fails for GET and HEAD methods, then the server must
/// return HTTP status code 304 (Not Modified). For methods that apply
/// server-side changes, the status code 412 (Precondition Failed) is used.
/// Note that the server generating a 304 response MUST generate any of the
/// following header fields that would have been sent in a 200 (OK) response
/// to the same request: Cache-Control, Content-Location, Date, ETag,
/// Expires, and Vary.
///
/// The comparison with the stored ETag uses the weak comparison algorithm,
/// meaning two files are considered identical not only if they are
/// identical byte to byte, but if the content is equivalent. For example,
/// two pages that would differ only by the date of generation in the footer
/// would be considered as identical.
///
/// When used in combination with If-Modified-Since, it has precedence (if
/// the server supports it).
///
/// There are two common use cases:
///
/// * For `GET` and `HEAD` methods, to update a cached entity that has an associated ETag.
/// * For other methods, and in particular for `PUT`, `If-None-Match` used with
/// the `*` value can be used to save a file not known to exist,
/// guaranteeing that another upload didn't happen before, losing the data
/// of the previous put; this problems is the variation of the lost update
/// problem.
(IfNoneMatch, IF_NONE_MATCH, "if-none-match");
/// Makes a request conditional based on range.
///
/// The If-Range HTTP request header makes a range request conditional: if
/// the condition is fulfilled, the range request will be issued and the
/// server sends back a 206 Partial Content answer with the appropriate
/// body. If the condition is not fulfilled, the full resource is sent back,
/// with a 200 OK status.
///
/// This header can be used either with a Last-Modified validator, or with
/// an ETag, but not with both.
///
/// The most common use case is to resume a download, to guarantee that the
/// stored resource has not been modified since the last fragment has been
/// received.
(IfRange, IF_RANGE, "if-range");
/// Makes the request conditional based on the last modification date.
///
/// The If-Unmodified-Since request HTTP header makes the request
/// conditional: the server will send back the requested resource, or accept
/// it in the case of a POST or another non-safe method, only if it has not
/// been last modified after the given date. If the request has been
/// modified after the given date, the response will be a 412 (Precondition
/// Failed) error.
///
/// There are two common use cases:
///
/// * In conjunction non-safe methods, like POST, it can be used to
/// implement an optimistic concurrency control, like done by some wikis:
/// editions are rejected if the stored document has been modified since the
/// original has been retrieved.
///
/// * In conjunction with a range request with a If-Range header, it can be
/// used to ensure that the new fragment requested comes from an unmodified
/// document.
(IfUnmodifiedSince, IF_UNMODIFIED_SINCE, "if-unmodified-since");
/// Content-Types that are acceptable for the response.
(LastModified, LAST_MODIFIED, "last-modified");
/// Allows the server to point an interested client to another resource
/// containing metadata about the requested resource.
(Link, LINK, "link");
/// Indicates the URL to redirect a page to.
///
/// The Location response header indicates the URL to redirect a page to. It
/// only provides a meaning when served with a 3xx status response.
///
/// The HTTP method used to make the new request to fetch the page pointed
/// to by Location depends of the original method and of the kind of
/// redirection:
///
/// * If 303 (See Also) responses always lead to the use of a GET method,
/// 307 (Temporary Redirect) and 308 (Permanent Redirect) don't change the
/// method used in the original request;
///
/// * 301 (Permanent Redirect) and 302 (Found) doesn't change the method
/// most of the time, though older user-agents may (so you basically don't
/// know).
///
/// All responses with one of these status codes send a Location header.
///
/// Beside redirect response, messages with 201 (Created) status also
/// include the Location header. It indicates the URL to the newly created
/// resource.
///
/// Location and Content-Location are different: Location indicates the
/// target of a redirection (or the URL of a newly created resource), while
/// Content-Location indicates the direct URL to use to access the resource
/// when content negotiation happened, without the need of further content
/// negotiation. Location is a header associated with the response, while
/// Content-Location is associated with the entity returned.
(Location, LOCATION, "location");
/// Indicates the max number of intermediaries the request should be sent
/// through.
(MaxForwards, MAX_FORWARDS, "max-forwards");
/// Indicates where a fetch originates from.
///
/// It doesn't include any path information, but only the server name. It is
/// sent with CORS requests, as well as with POST requests. It is similar to
/// the Referer header, but, unlike this header, it doesn't disclose the
/// whole path.
(Origin, ORIGIN, "origin");
/// HTTP/1.0 header usually used for backwards compatibility.
///
/// The Pragma HTTP/1.0 general header is an implementation-specific header
/// that may have various effects along the request-response chain. It is
/// used for backwards compatibility with HTTP/1.0 caches where the
/// Cache-Control HTTP/1.1 header is not yet present.
(Pragma, PRAGMA, "pragma");
/// Defines the authentication method that should be used to gain access to
/// a proxy.
///
/// Unlike `www-authenticate`, the `proxy-authenticate` header field applies
/// only to the next outbound client on the response chain. This is because
/// only the client that chose a given proxy is likely to have the
/// credentials necessary for authentication. However, when multiple proxies
/// are used within the same administrative domain, such as office and
/// regional caching proxies within a large corporate network, it is common
/// for credentials to be generated by the user agent and passed through the
/// hierarchy until consumed. Hence, in such a configuration, it will appear
/// as if Proxy-Authenticate is being forwarded because each proxy will send
/// the same challenge set.
///
/// The `proxy-authenticate` header is sent along with a `407 Proxy
/// Authentication Required`.
(ProxyAuthenticate, PROXY_AUTHENTICATE, "proxy-authenticate");
/// Contains the credentials to authenticate a user agent to a proxy server.
///
/// This header is usually included after the server has responded with a
/// 407 Proxy Authentication Required status and the Proxy-Authenticate
/// header.
(ProxyAuthorization, PROXY_AUTHORIZATION, "proxy-authorization");
/// Associates a specific cryptographic public key with a certain server.
///
/// This decreases the risk of MITM attacks with forged certificates. If one
/// or several keys are pinned and none of them are used by the server, the
/// browser will not accept the response as legitimate, and will not display
/// it.
(PublicKeyPins, PUBLIC_KEY_PINS, "public-key-pins");
/// Sends reports of pinning violation to the report-uri specified in the
/// header.
///
/// Unlike `Public-Key-Pins`, this header still allows browsers to connect
/// to the server if the pinning is violated.
(PublicKeyPinsReportOnly, PUBLIC_KEY_PINS_REPORT_ONLY, "public-key-pins-report-only");
/// Indicates the part of a document that the server should return.
///
/// Several parts can be requested with one Range header at once, and the
/// server may send back these ranges in a multipart document. If the server
/// sends back ranges, it uses the 206 Partial Content for the response. If
/// the ranges are invalid, the server returns the 416 Range Not Satisfiable
/// error. The server can also ignore the Range header and return the whole
/// document with a 200 status code.
(Range, RANGE, "range");
/// Contains the address of the previous web page from which a link to the
/// currently requested page was followed.
///
/// The Referer header allows servers to identify where people are visiting
/// them from and may use that data for analytics, logging, or optimized
/// caching, for example.
(Referer, REFERER, "referer");
/// Governs which referrer information should be included with requests
/// made.
(ReferrerPolicy, REFERRER_POLICY, "referrer-policy");
/// Informs the web browser that the current page or frame should be
/// refreshed.
(Refresh, REFRESH, "refresh");
/// The Retry-After response HTTP header indicates how long the user agent
/// should wait before making a follow-up request. There are two main cases
/// this header is used:
///
/// * When sent with a 503 (Service Unavailable) response, it indicates how
/// long the service is expected to be unavailable.
///
/// * When sent with a redirect response, such as 301 (Moved Permanently),
/// it indicates the minimum time that the user agent is asked to wait
/// before issuing the redirected request.
(RetryAfter, RETRY_AFTER, "retry-after");
/// Contains information about the software used by the origin server to
/// handle the request.
///
/// Overly long and detailed Server values should be avoided as they
/// potentially reveal internal implementation details that might make it
/// (slightly) easier for attackers to find and exploit known security
/// holes.
(Server, SERVER, "server");
/// Used to send cookies from the server to the user agent.
(SetCookie, SET_COOKIE, "set-cookie");
/// Tells the client to communicate with HTTPS instead of using HTTP.
(StrictTransportSecurity, STRICT_TRANSPORT_SECURITY, "strict-transport-security");
/// Informs the server of transfer encodings willing to be accepted as part
/// of the response.
///
/// See also the Transfer-Encoding response header for more details on
/// transfer encodings. Note that chunked is always acceptable for HTTP/1.1
/// recipients and you that don't have to specify "chunked" using the TE
/// header. However, it is useful for setting if the client is accepting
/// trailer fields in a chunked transfer coding using the "trailers" value.
(Te, TE, "te");
/// Allows the sender to include additional fields at the end of chunked
/// messages.
(Trailer, TRAILER, "trailer");
/// Specifies the form of encoding used to safely transfer the entity to the
/// client.
///
/// `transfer-encoding` is a hop-by-hop header, that is applying to a
/// message between two nodes, not to a resource itself. Each segment of a
/// multi-node connection can use different `transfer-encoding` values. If
/// you want to compress data over the whole connection, use the end-to-end
/// header `content-encoding` header instead.
///
/// When present on a response to a `HEAD` request that has no body, it
/// indicates the value that would have applied to the corresponding `GET`
/// message.
(TransferEncoding, TRANSFER_ENCODING, "transfer-encoding");
/// Contains a string that allows identifying the requesting client's
/// software.
(UserAgent, USER_AGENT, "user-agent");
/// Used as part of the exchange to upgrade the protocol.
(Upgrade, UPGRADE, "upgrade");
/// Sends a signal to the server expressing the client’s preference for an
/// encrypted and authenticated response.
(UpgradeInsecureRequests, UPGRADE_INSECURE_REQUESTS, "upgrade-insecure-requests");
/// Determines how to match future requests with cached responses.
///
/// The `vary` HTTP response header determines how to match future request
/// headers to decide whether a cached response can be used rather than
/// requesting a fresh one from the origin server. It is used by the server
/// to indicate which headers it used when selecting a representation of a
/// resource in a content negotiation algorithm.
///
/// The `vary` header should be set on a 304 Not Modified response exactly
/// like it would have been set on an equivalent 200 OK response.
(Vary, VARY, "vary");
/// Added by proxies to track routing.
///
/// The `via` general header is added by proxies, both forward and reverse
/// proxies, and can appear in the request headers and the response headers.
/// It is used for tracking message forwards, avoiding request loops, and
/// identifying the protocol capabilities of senders along the
/// request/response chain.
(Via, VIA, "via");
/// General HTTP header contains information about possible problems with
/// the status of the message.
///
/// More than one `warning` header may appear in a response. Warning header
/// fields can in general be applied to any message, however some warn-codes
/// are specific to caches and can only be applied to response messages.
(Warning, WARNING, "warning");
/// Defines the authentication method that should be used to gain access to
/// a resource.
(WwwAuthenticate, WWW_AUTHENTICATE, "www-authenticate");
/// Marker used by the server to indicate that the MIME types advertised in
/// the `content-type` headers should not be changed and be followed.
///
/// This allows to opt-out of MIME type sniffing, or, in other words, it is
/// a way to say that the webmasters knew what they were doing.
///
/// This header was introduced by Microsoft in IE 8 as a way for webmasters
/// to block content sniffing that was happening and could transform
/// non-executable MIME types into executable MIME types. Since then, other
/// browsers have introduced it, even if their MIME sniffing algorithms were
/// less aggressive.
///
/// Site security testers usually expect this header to be set.
(XContentTypeOptions, X_CONTENT_TYPE_OPTIONS, "x-content-type-options");
/// Controls DNS prefetching.
///
/// The `x-dns-prefetch-control` HTTP response header controls DNS
/// prefetching, a feature by which browsers proactively perform domain name
/// resolution on both links that the user may choose to follow as well as
/// URLs for items referenced by the document, including images, CSS,
/// JavaScript, and so forth.
///
/// This prefetching is performed in the background, so that the DNS is
/// likely to have been resolved by the time the referenced items are
/// needed. This reduces latency when the user clicks a link.
(XDnsPrefetchControl, X_DNS_PREFETCH_CONTROL, "x-dns-prefetch-control");
/// Indicates whether or not a browser should be allowed to render a page in
/// a frame.
///
/// Sites can use this to avoid clickjacking attacks, by ensuring that their
/// content is not embedded into other sites.
///
/// The added security is only provided if the user accessing the document
/// is using a browser supporting `x-frame-options`.
(XFrameOptions, X_FRAME_OPTIONS, "x-frame-options");
/// Stop pages from loading when an XSS attack is detected.
///
/// The HTTP X-XSS-Protection response header is a feature of Internet
/// Explorer, Chrome and Safari that stops pages from loading when they
/// detect reflected cross-site scripting (XSS) attacks. Although these
/// protections are largely unnecessary in modern browsers when sites
/// implement a strong Content-Security-Policy that disables the use of
/// inline JavaScript ('unsafe-inline'), they can still provide protections
/// for users of older web browsers that don't yet support CSP.
(XXssProtection, X_XSS_PROTECTION, "x-xss-protection");
}
/// Valid header name characters
///
/// ```not_rust
/// field-name = token
/// token = 1*<any CHAR except CTLs or separators>
/// separators = "(" | ")" | "<" | ">" | "@"
/// | "," | ";" | ":" | "\" | <">
/// | "/" | "[" | "]" | "?" | "="
/// | "{" | "}" | SP | HT
/// ```
const HEADER_CHARS: [u8; 256] = [
// 0 1 2 3 4 5 6 7 8 9
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 1x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 2x
0, 0, 0, b'!', b'"', b'#', b'$', b'%', b'&', b'\'', // 3x
0, 0, b'*', b'+', 0, b'-', b'.', 0, b'0', b'1', // 4x
b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', 0, 0, // 5x
0, 0, 0, 0, 0, b'a', b'b', b'c', b'd', b'e', // 6x
b'f', b'g', b'h', b'i', b'j', b'k', b'l', b'm', b'n', b'o', // 7x
b'p', b'q', b'r', b's', b't', b'u', b'v', b'w', b'x', b'y', // 8x
b'z', 0, 0, 0, 0, b'_', 0, b'a', b'b', b'c', // 9x
b'd', b'e', b'f', b'g', b'h', b'i', b'j', b'k', b'l', b'm', // 10x
b'n', b'o', b'p', b'q', b'r', b's', b't', b'u', b'v', b'w', // 11x
b'x', b'y', b'z', 0, b'|', 0, b'~', 0, 0, 0, // 12x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 13x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 14x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 15x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 16x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 17x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 18x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 19x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 21x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 22x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 23x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 24x
0, 0, 0, 0, 0, 0 // 25x
];
const HEADER_CHARS_H2: [u8; 256] = [
// 0 1 2 3 4 5 6 7 8 9
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 1x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 2x
0, 0, 0, b'!', b'"', b'#', b'$', b'%', b'&', b'\'', // 3x
0, 0, b'*', b'+', 0, b'-', b'.', 0, b'0', b'1', // 4x
b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', 0, 0, // 5x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 6x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 7x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 8x
0, 0, 0, 0, 0, b'_', 0, b'a', b'b', b'c', // 9x
b'd', b'e', b'f', b'g', b'h', b'i', b'j', b'k', b'l', b'm', // 10x
b'n', b'o', b'p', b'q', b'r', b's', b't', b'u', b'v', b'w', // 11x
b'x', b'y', b'z', 0, b'|', 0, b'~', 0, 0, 0, // 12x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 13x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 14x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 15x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 16x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 17x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 18x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 19x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 21x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 22x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 23x
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 24x
0, 0, 0, 0, 0, 0 // 25x
];
macro_rules! eq {
($v:ident[$n:expr] == $a:tt) => {
$v[$n] == $a
};
($v:ident[$n:expr] == $a:tt $($rest:tt)+) => {
$v[$n] == $a && eq!($v[($n+1)] == $($rest)+)
};
($v:ident == $a:tt $($rest:tt)*) => {
$v[0] == $a && eq!($v[1] == $($rest)*)
};
}
fn parse_hdr<'a>(data: &'a [u8], b: &'a mut [u8; 64], table: &[u8; 256])
-> Result<HdrName<'a>, InvalidHeaderName>
{
use self::StandardHeader::*;
let len = data.len();
let validate = |buf: &'a [u8], len: usize| {
let buf = &buf[..len];
if buf.iter().any(|&b| b == 0) {
Err(InvalidHeaderName::new())
} else {
Ok(HdrName::custom(buf, true))
}
};
macro_rules! to_lower {
($d:ident, $src:ident, 1) => { $d[0] = table[$src[0] as usize]; };
($d:ident, $src:ident, 2) => { to_lower!($d, $src, 1); $d[1] = table[$src[1] as usize]; };
($d:ident, $src:ident, 3) => { to_lower!($d, $src, 2); $d[2] = table[$src[2] as usize]; };
($d:ident, $src:ident, 4) => { to_lower!($d, $src, 3); $d[3] = table[$src[3] as usize]; };
($d:ident, $src:ident, 5) => { to_lower!($d, $src, 4); $d[4] = table[$src[4] as usize]; };
($d:ident, $src:ident, 6) => { to_lower!($d, $src, 5); $d[5] = table[$src[5] as usize]; };
($d:ident, $src:ident, 7) => { to_lower!($d, $src, 6); $d[6] = table[$src[6] as usize]; };
($d:ident, $src:ident, 8) => { to_lower!($d, $src, 7); $d[7] = table[$src[7] as usize]; };
($d:ident, $src:ident, 9) => { to_lower!($d, $src, 8); $d[8] = table[$src[8] as usize]; };
($d:ident, $src:ident, 10) => { to_lower!($d, $src, 9); $d[9] = table[$src[9] as usize]; };
($d:ident, $src:ident, 11) => { to_lower!($d, $src, 10); $d[10] = table[$src[10] as usize]; };
($d:ident, $src:ident, 12) => { to_lower!($d, $src, 11); $d[11] = table[$src[11] as usize]; };
($d:ident, $src:ident, 13) => { to_lower!($d, $src, 12); $d[12] = table[$src[12] as usize]; };
($d:ident, $src:ident, 14) => { to_lower!($d, $src, 13); $d[13] = table[$src[13] as usize]; };
($d:ident, $src:ident, 15) => { to_lower!($d, $src, 14); $d[14] = table[$src[14] as usize]; };
($d:ident, $src:ident, 16) => { to_lower!($d, $src, 15); $d[15] = table[$src[15] as usize]; };
($d:ident, $src:ident, 17) => { to_lower!($d, $src, 16); $d[16] = table[$src[16] as usize]; };
($d:ident, $src:ident, 18) => { to_lower!($d, $src, 17); $d[17] = table[$src[17] as usize]; };
($d:ident, $src:ident, 19) => { to_lower!($d, $src, 18); $d[18] = table[$src[18] as usize]; };
($d:ident, $src:ident, 20) => { to_lower!($d, $src, 19); $d[19] = table[$src[19] as usize]; };
($d:ident, $src:ident, 21) => { to_lower!($d, $src, 20); $d[20] = table[$src[20] as usize]; };
($d:ident, $src:ident, 22) => { to_lower!($d, $src, 21); $d[21] = table[$src[21] as usize]; };
($d:ident, $src:ident, 23) => { to_lower!($d, $src, 22); $d[22] = table[$src[22] as usize]; };
($d:ident, $src:ident, 24) => { to_lower!($d, $src, 23); $d[23] = table[$src[23] as usize]; };
($d:ident, $src:ident, 25) => { to_lower!($d, $src, 24); $d[24] = table[$src[24] as usize]; };
($d:ident, $src:ident, 26) => { to_lower!($d, $src, 25); $d[25] = table[$src[25] as usize]; };
($d:ident, $src:ident, 27) => { to_lower!($d, $src, 26); $d[26] = table[$src[26] as usize]; };
($d:ident, $src:ident, 28) => { to_lower!($d, $src, 27); $d[27] = table[$src[27] as usize]; };
($d:ident, $src:ident, 29) => { to_lower!($d, $src, 28); $d[28] = table[$src[28] as usize]; };
($d:ident, $src:ident, 30) => { to_lower!($d, $src, 29); $d[29] = table[$src[29] as usize]; };
($d:ident, $src:ident, 31) => { to_lower!($d, $src, 30); $d[30] = table[$src[30] as usize]; };
($d:ident, $src:ident, 32) => { to_lower!($d, $src, 31); $d[31] = table[$src[31] as usize]; };
($d:ident, $src:ident, 33) => { to_lower!($d, $src, 32); $d[32] = table[$src[32] as usize]; };
($d:ident, $src:ident, 34) => { to_lower!($d, $src, 33); $d[33] = table[$src[33] as usize]; };
($d:ident, $src:ident, 35) => { to_lower!($d, $src, 34); $d[34] = table[$src[34] as usize]; };
}
assert!(len < super::MAX_HEADER_NAME_LEN,
"header name too long -- max length is {}",
super::MAX_HEADER_NAME_LEN);
match len {
0 => {
Err(InvalidHeaderName::new())
}
2 => {
to_lower!(b, data, 2);
if eq!(b == b't' b'e') {
Ok(Te.into())
} else {
validate(b, len)
}
}
3 => {
to_lower!(b, data, 3);
if eq!(b == b'a' b'g' b'e') {
Ok(Age.into())
} else if eq!(b == b'v' b'i' b'a') {
Ok(Via.into())
} else if eq!(b == b'd' b'n' b't') {
Ok(Dnt.into())
} else {
validate(b, len)
}
}
4 => {
to_lower!(b, data, 4);
if eq!(b == b'd' b'a' b't' b'e') {
Ok(Date.into())
} else if eq!(b == b'e' b't' b'a' b'g') {
Ok(Etag.into())
} else if eq!(b == b'f' b'r' b'o' b'm') {
Ok(From.into())
} else if eq!(b == b'h' b'o' b's' b't') {
Ok(Host.into())
} else if eq!(b == b'l' b'i' b'n' b'k') {
Ok(Link.into())
} else if eq!(b == b'v' b'a' b'r' b'y') {
Ok(Vary.into())
} else {
validate(b, len)
}
}
5 => {
to_lower!(b, data, 5);
if eq!(b == b'a' b'l' b'l' b'o' b'w') {
Ok(Allow.into())
} else if eq!(b == b'r' b'a' b'n' b'g' b'e') {
Ok(Range.into())
} else {
validate(b, len)
}
}
6 => {
to_lower!(b, data, 6);
if eq!(b == b'a' b'c' b'c' b'e' b'p' b't') {
return Ok(Accept.into())
} else if eq!(b == b'c' b'o' b'o' b'k' b'i' b'e') {
return Ok(Cookie.into())
} else if eq!(b == b'e' b'x' b'p' b'e' b'c' b't') {
return Ok(Expect.into())
} else if eq!(b == b'o' b'r' b'i' b'g' b'i' b'n') {
return Ok(Origin.into())
} else if eq!(b == b'p' b'r' b'a' b'g' b'm' b'a') {
return Ok(Pragma.into())
} else if b[0] == b's' {
if eq!(b[1] == b'e' b'r' b'v' b'e' b'r') {
return Ok(Server.into())
}
}
validate(b, len)
}
7 => {
to_lower!(b, data, 7);
if eq!(b == b'a' b'l' b't' b'-' b's' b'v' b'c') {
Ok(AltSvc.into())
} else if eq!(b == b'e' b'x' b'p' b'i' b'r' b'e' b's') {
Ok(Expires.into())
} else if eq!(b == b'r' b'e' b'f' b'e' b'r' b'e' b'r') {
Ok(Referer.into())
} else if eq!(b == b'r' b'e' b'f' b'r' b'e' b's' b'h') {
Ok(Refresh.into())
} else if eq!(b == b't' b'r' b'a' b'i' b'l' b'e' b'r') {
Ok(Trailer.into())
} else if eq!(b == b'u' b'p' b'g' b'r' b'a' b'd' b'e') {
Ok(Upgrade.into())
} else if eq!(b == b'w' b'a' b'r' b'n' b'i' b'n' b'g') {
Ok(Warning.into())
} else {
validate(b, len)
}
}
8 => {
to_lower!(b, data, 8);
if eq!(b == b'i' b'f' b'-') {
if eq!(b[3] == b'm' b'a' b't' b'c' b'h') {
return Ok(IfMatch.into())
} else if eq!(b[3] == b'r' b'a' b'n' b'g' b'e') {
return Ok(IfRange.into())
}
} else if eq!(b == b'l' b'o' b'c' b'a' b't' b'i' b'o' b'n') {
return Ok(Location.into())
}
validate(b, len)
}
9 => {
to_lower!(b, data, 9);
if eq!(b == b'f' b'o' b'r' b'w' b'a' b'r' b'd' b'e' b'd') {
Ok(Forwarded.into())
} else {
validate(b, len)
}
}
10 => {
to_lower!(b, data, 10);
if eq!(b == b'c' b'o' b'n' b'n' b'e' b'c' b't' b'i' b'o' b'n') {
Ok(Connection.into())
} else if eq!(b == b's' b'e' b't' b'-' b'c' b'o' b'o' b'k' b'i' b'e') {
Ok(SetCookie.into())
} else if eq!(b == b'u' b's' b'e' b'r' b'-' b'a' b'g' b'e' b'n' b't') {
Ok(UserAgent.into())
} else {
validate(b, len)
}
}
11 => {
to_lower!(b, data, 11);
if eq!(b == b'r' b'e' b't' b'r' b'y' b'-' b'a' b'f' b't' b'e' b'r') {
Ok(RetryAfter.into())
} else {
validate(b, len)
}
}
12 => {
to_lower!(b, data, 12);
if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b't' b'y' b'p' b'e') {
Ok(ContentType.into())
} else if eq!(b == b'm' b'a' b'x' b'-' b'f' b'o' b'r' b'w' b'a' b'r' b'd' b's') {
Ok(MaxForwards.into())
} else {
validate(b, len)
}
}
13 => {
to_lower!(b, data, 13);
if b[0] == b'a' {
if eq!(b[1] == b'c' b'c' b'e' b'p' b't' b'-' b'r' b'a' b'n' b'g' b'e' b's') {
return Ok(AcceptRanges.into())
} else if eq!(b[1] == b'u' b't' b'h' b'o' b'r' b'i' b'z' b'a' b't' b'i' b'o' b'n') {
return Ok(Authorization.into())
}
} else if b[0] == b'c' {
if eq!(b[1] == b'a' b'c' b'h' b'e' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l') {
return Ok(CacheControl.into())
} else if eq!(b[1] == b'o' b'n' b't' b'e' b'n' b't' b'-' b'r' b'a' b'n' b'g' b'e' ) {
return Ok(ContentRange.into())
}
} else if eq!(b == b'i' b'f' b'-' b'n' b'o' b'n' b'e' b'-' b'm' b'a' b't' b'c' b'h') {
return Ok(IfNoneMatch.into())
} else if eq!(b == b'l' b'a' b's' b't' b'-' b'm' b'o' b'd' b'i' b'f' b'i' b'e' b'd') {
return Ok(LastModified.into())
}
validate(b, len)
}
14 => {
to_lower!(b, data, 14);
if eq!(b == b'a' b'c' b'c' b'e' b'p' b't' b'-' b'c' b'h' b'a' b'r' b's' b'e' b't') {
Ok(AcceptCharset.into())
} else if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b'l' b'e' b'n' b'g' b't' b'h') {
Ok(ContentLength.into())
} else {
validate(b, len)
}
}
15 => {
to_lower!(b, data, 15);
if eq!(b == b'a' b'c' b'c' b'e' b'p' b't' b'-') { // accept-
if eq!(b[7] == b'e' b'n' b'c' b'o' b'd' b'i' b'n' b'g') {
return Ok(AcceptEncoding.into())
} else if eq!(b[7] == b'l' b'a' b'n' b'g' b'u' b'a' b'g' b'e') {
return Ok(AcceptLanguage.into())
}
} else if eq!(b == b'p' b'u' b'b' b'l' b'i' b'c' b'-' b'k' b'e' b'y' b'-' b'p' b'i' b'n' b's') {
return Ok(PublicKeyPins.into())
} else if eq!(b == b'x' b'-' b'f' b'r' b'a' b'm' b'e' b'-' b'o' b'p' b't' b'i' b'o' b'n' b's') {
return Ok(XFrameOptions.into())
}
else if eq!(b == b'r' b'e' b'f' b'e' b'r' b'r' b'e' b'r' b'-' b'p' b'o' b'l' b'i' b'c' b'y') {
return Ok(ReferrerPolicy.into())
}
validate(b, len)
}
16 => {
to_lower!(b, data, 16);
if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-') {
if eq!(b[8] == b'l' b'a' b'n' b'g' b'u' b'a' b'g' b'e') {
return Ok(ContentLanguage.into())
} else if eq!(b[8] == b'l' b'o' b'c' b'a' b't' b'i' b'o' b'n') {
return Ok(ContentLocation.into())
} else if eq!(b[8] == b'e' b'n' b'c' b'o' b'd' b'i' b'n' b'g') {
return Ok(ContentEncoding.into())
}
} else if eq!(b == b'w' b'w' b'w' b'-' b'a' b'u' b't' b'h' b'e' b'n' b't' b'i' b'c' b'a' b't' b'e') {
return Ok(WwwAuthenticate.into())
} else if eq!(b == b'x' b'-' b'x' b's' b's' b'-' b'p' b'r' b'o' b't' b'e' b'c' b't' b'i' b'o' b'n') {
return Ok(XXssProtection.into())
}
validate(b, len)
}
17 => {
to_lower!(b, data, 17);
if eq!(b == b't' b'r' b'a' b'n' b's' b'f' b'e' b'r' b'-' b'e' b'n' b'c' b'o' b'd' b'i' b'n' b'g') {
Ok(TransferEncoding.into())
} else if eq!(b == b'i' b'f' b'-' b'm' b'o' b'd' b'i' b'f' b'i' b'e' b'd' b'-' b's' b'i' b'n' b'c' b'e') {
Ok(IfModifiedSince.into())
} else {
validate(b, len)
}
}
18 => {
to_lower!(b, data, 18);
if eq!(b == b'p' b'r' b'o' b'x' b'y' b'-' b'a' b'u' b't' b'h' b'e' b'n' b't' b'i' b'c' b'a' b't' b'e') {
Ok(ProxyAuthenticate.into())
} else {
validate(b, len)
}
}
19 => {
to_lower!(b, data, 19);
if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b'd' b'i' b's' b'p' b'o' b's' b'i' b't' b'i' b'o' b'n') {
Ok(ContentDisposition.into())
} else if eq!(b == b'i' b'f' b'-' b'u' b'n' b'm' b'o' b'd' b'i' b'f' b'i' b'e' b'd' b'-' b's' b'i' b'n' b'c' b'e') {
Ok(IfUnmodifiedSince.into())
} else if eq!(b == b'p' b'r' b'o' b'x' b'y' b'-' b'a' b'u' b't' b'h' b'o' b'r' b'i' b'z' b'a' b't' b'i' b'o' b'n') {
Ok(ProxyAuthorization.into())
} else {
validate(b, len)
}
}
22 => {
to_lower!(b, data, 22);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-' b'm' b'a' b'x' b'-' b'a' b'g' b'e') {
Ok(AccessControlMaxAge.into())
} else if eq!(b == b'x' b'-' b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b't' b'y' b'p' b'e' b'-' b'o' b'p' b't' b'i' b'o' b'n' b's') {
Ok(XContentTypeOptions.into())
} else if eq!(b == b'x' b'-' b'd' b'n' b's' b'-' b'p' b'r' b'e' b'f' b'e' b't' b'c' b'h' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l') {
Ok(XDnsPrefetchControl.into())
} else {
validate(b, len)
}
}
23 => {
to_lower!(b, data, 23);
if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b's' b'e' b'c' b'u' b'r' b'i' b't' b'y' b'-' b'p' b'o' b'l' b'i' b'c' b'y') {
Ok(ContentSecurityPolicy.into())
} else {
validate(b, len)
}
}
25 => {
to_lower!(b, data, 25);
if eq!(b == b's' b't' b'r' b'i' b'c' b't' b'-' b't' b'r' b'a' b'n' b's' b'p' b'o' b'r' b't' b'-' b's' b'e' b'c' b'u' b'r' b'i' b't' b'y') {
Ok(StrictTransportSecurity.into())
} else if eq!(b == b'u' b'p' b'g' b'r' b'a' b'd' b'e' b'-' b'i' b'n' b's' b'e' b'c' b'u' b'r' b'e' b'-' b'r' b'e' b'q' b'u' b'e' b's' b't' b's') {
Ok(UpgradeInsecureRequests.into())
} else {
validate(b, len)
}
}
27 => {
to_lower!(b, data, 27);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-' b'a' b'l' b'l' b'o' b'w' b'-' b'o' b'r' b'i' b'g' b'i' b'n') {
Ok(AccessControlAllowOrigin.into())
} else if eq!(b == b'p' b'u' b'b' b'l' b'i' b'c' b'-' b'k' b'e' b'y' b'-' b'p' b'i' b'n' b's' b'-' b'r' b'e' b'p' b'o' b'r' b't' b'-' b'o' b'n' b'l' b'y') {
Ok(PublicKeyPinsReportOnly.into())
} else {
validate(b, len)
}
}
28 => {
to_lower!(b, data, 28);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-' b'a' b'l' b'l' b'o' b'w' b'-') {
if eq!(b[21] == b'h' b'e' b'a' b'd' b'e' b'r' b's') {
return Ok(AccessControlAllowHeaders.into())
} else if eq!(b[21] == b'm' b'e' b't' b'h' b'o' b'd' b's') {
return Ok(AccessControlAllowMethods.into())
}
}
validate(b, len)
}
29 => {
to_lower!(b, data, 29);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-') {
if eq!(b[15] == b'e' b'x' b'p' b'o' b's' b'e' b'-' b'h' b'e' b'a' b'd' b'e' b'r' b's') {
return Ok(AccessControlExposeHeaders.into())
} else if eq!(b[15] == b'r' b'e' b'q' b'u' b'e' b's' b't' b'-' b'm' b'e' b't' b'h' b'o' b'd') {
return Ok(AccessControlRequestMethod.into())
}
}
validate(b, len)
}
30 => {
to_lower!(b, data, 30);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-' b'r' b'e' b'q' b'u' b'e' b's' b't' b'-' b'h' b'e' b'a' b'd' b'e' b'r' b's') {
Ok(AccessControlRequestHeaders.into())
} else {
validate(b, len)
}
}
32 => {
to_lower!(b, data, 32);
if eq!(b == b'a' b'c' b'c' b'e' b's' b's' b'-' b'c' b'o' b'n' b't' b'r' b'o' b'l' b'-' b'a' b'l' b'l' b'o' b'w' b'-' b'c' b'r' b'e' b'd' b'e' b'n' b't' b'i' b'a' b'l' b's') {
Ok(AccessControlAllowCredentials.into())
} else {
validate(b, len)
}
}
35 => {
to_lower!(b, data, 35);
if eq!(b == b'c' b'o' b'n' b't' b'e' b'n' b't' b'-' b's' b'e' b'c' b'u' b'r' b'i' b't' b'y' b'-' b'p' b'o' b'l' b'i' b'c' b'y' b'-' b'r' b'e' b'p' b'o' b'r' b't' b'-' b'o' b'n' b'l' b'y') {
Ok(ContentSecurityPolicyReportOnly.into())
} else {
validate(b, len)
}
}
_ => {
if len < 64 {
for i in 0..len {
b[i] = table[data[i] as usize];
}
validate(b, len)
} else {
Ok(HdrName::custom(data, false))
}
}
}
}
impl<'a> From<StandardHeader> for HdrName<'a> {
fn from(hdr: StandardHeader) -> HdrName<'a> {
HdrName { inner: Repr::Standard(hdr) }
}
}
impl HeaderName {
/// Converts a slice of bytes to an HTTP header name.
///
/// This function normalizes the input.
pub fn from_bytes(src: &[u8]) -> Result<HeaderName, InvalidHeaderName> {
let mut buf = unsafe { mem::uninitialized() };
match parse_hdr(src, &mut buf, &HEADER_CHARS)?.inner {
Repr::Standard(std) => Ok(std.into()),
Repr::Custom(MaybeLower { buf, lower: true }) => {
let buf = Bytes::from(buf);
let val = unsafe { ByteStr::from_utf8_unchecked(buf) };
Ok(Custom(val).into())
}
Repr::Custom(MaybeLower { buf, lower: false }) => {
use bytes::{BufMut};
let mut dst = BytesMut::with_capacity(buf.len());
for b in buf.iter() {
let b = HEADER_CHARS[*b as usize];
if b == 0 {
return Err(InvalidHeaderName::new());
}
dst.put(b);
}
let val = unsafe { ByteStr::from_utf8_unchecked(dst.freeze()) };
Ok(Custom(val).into())
}
}
}
/// Converts a slice of bytes to an HTTP header name.
///
/// This function expects the input to only contain lowercase characters.
/// This is useful when decoding HTTP/2.0 headers. The HTTP/2.0
/// specification requires that all headers be represented in lower case.
///
/// # Examples
///
/// ```
/// # use http::header::*;
///
/// // Parsing a lower case header
/// let hdr = HeaderName::from_lowercase(b"content-length").unwrap();
/// assert_eq!(CONTENT_LENGTH, hdr);
///
/// // Parsing a header that contains uppercase characters
/// assert!(HeaderName::from_lowercase(b"Content-Length").is_err());
/// ```
pub fn from_lowercase(src: &[u8]) -> Result<HeaderName, InvalidHeaderName> {
let mut buf = unsafe { mem::uninitialized() };
match parse_hdr(src, &mut buf, &HEADER_CHARS_H2)?.inner {
Repr::Standard(std) => Ok(std.into()),
Repr::Custom(MaybeLower { buf, lower: true }) => {
let buf = Bytes::from(buf);
let val = unsafe { ByteStr::from_utf8_unchecked(buf) };
Ok(Custom(val).into())
}
Repr::Custom(MaybeLower { buf, lower: false }) => {
for &b in buf.iter() {
if b != HEADER_CHARS[b as usize] {
return Err(InvalidHeaderName::new());
}
}
let buf = Bytes::from(buf);
let val = unsafe { ByteStr::from_utf8_unchecked(buf) };
Ok(Custom(val).into())
}
}
}
/// Returns a `str` representation of the header.
///
/// The returned string will always be lower case.
#[inline]
pub fn as_str(&self) -> &str {
match self.inner {
Repr::Standard(v) => v.as_str(),
Repr::Custom(ref v) => &*v.0,
}
}
}
impl FromStr for HeaderName {
type Err = InvalidHeaderName;
fn from_str(s: &str) -> Result<HeaderName, InvalidHeaderName> {
HeaderName::from_bytes(s.as_bytes())
.map_err(|_| InvalidHeaderName {
_priv: (),
})
}
}
impl AsRef<str> for HeaderName {
fn as_ref(&self) -> &str {
self.as_str()
}
}
impl AsRef<[u8]> for HeaderName {
fn as_ref(&self) -> &[u8] {
self.as_str().as_bytes()
}
}
impl Borrow<str> for HeaderName {
fn borrow(&self) -> &str {
self.as_str()
}
}
impl fmt::Debug for HeaderName {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
fmt::Debug::fmt(self.as_str(), fmt)
}
}
impl InvalidHeaderName {
fn new() -> InvalidHeaderName {
InvalidHeaderName { _priv: () }
}
}
impl<'a> From<&'a HeaderName> for HeaderName {
fn from(src: &'a HeaderName) -> HeaderName {
src.clone()
}
}
#[doc(hidden)]
impl<T> From<Repr<T>> for Bytes
where T: Into<Bytes> {
fn from(repr: Repr<T>) -> Bytes {
match repr {
Repr::Standard(header) =>
Bytes::from_static(header.as_str().as_bytes()),
Repr::Custom(header) => header.into()
}
}
}
impl From<Custom> for Bytes {
#[inline]
fn from(Custom(inner): Custom) -> Bytes {
Bytes::from(inner)
}
}
impl From<HeaderName> for Bytes {
#[inline]
fn from(name: HeaderName) -> Bytes {
name.inner.into()
}
}
impl<'a> HttpTryFrom<&'a str> for HeaderName {
type Error = InvalidHeaderName;
#[inline]
fn try_from(s: &'a str) -> Result<Self, Self::Error> {
Self::from_bytes(s.as_bytes())
}
}
impl<'a> HttpTryFrom<&'a [u8]> for HeaderName {
type Error = InvalidHeaderName;
#[inline]
fn try_from(s: &'a [u8]) -> Result<Self, Self::Error> {
Self::from_bytes(s)
}
}
impl HttpTryFrom<Bytes> for HeaderName {
type Error = InvalidHeaderNameBytes;
#[inline]
fn try_from(bytes: Bytes) -> Result<Self, Self::Error> {
Self::from_bytes(bytes.as_ref()).map_err(InvalidHeaderNameBytes)
}
}
#[doc(hidden)]
impl From<StandardHeader> for HeaderName {
fn from(src: StandardHeader) -> HeaderName {
HeaderName {
inner: Repr::Standard(src),
}
}
}
#[doc(hidden)]
impl From<Custom> for HeaderName {
fn from(src: Custom) -> HeaderName {
HeaderName { inner: Repr::Custom(src) }
}
}
impl<'a> PartialEq<&'a HeaderName> for HeaderName {
#[inline]
fn eq(&self, other: &&'a HeaderName) -> bool {
*self == **other
}
}
impl<'a> PartialEq<HeaderName> for &'a HeaderName {
#[inline]
fn eq(&self, other: &HeaderName) -> bool {
*other == *self
}
}
impl PartialEq<str> for HeaderName {
/// Performs a case-insensitive comparison of the string against the header
/// name
///
/// # Examples
///
/// ```
/// use http::header::CONTENT_LENGTH;
///
/// assert_eq!(CONTENT_LENGTH, "content-length");
/// assert_eq!(CONTENT_LENGTH, "Content-Length");
/// assert_ne!(CONTENT_LENGTH, "content length");
/// ```
#[inline]
fn eq(&self, other: &str) -> bool {
eq_ignore_ascii_case(self.as_ref(), other.as_bytes())
}
}
impl PartialEq<HeaderName> for str {
/// Performs a case-insensitive comparison of the string against the header
/// name
///
/// # Examples
///
/// ```
/// use http::header::CONTENT_LENGTH;
///
/// assert_eq!(CONTENT_LENGTH, "content-length");
/// assert_eq!(CONTENT_LENGTH, "Content-Length");
/// assert_ne!(CONTENT_LENGTH, "content length");
/// ```
#[inline]
fn eq(&self, other: &HeaderName) -> bool {
*other == *self
}
}
impl<'a> PartialEq<&'a str> for HeaderName {
/// Performs a case-insensitive comparison of the string against the header
/// name
#[inline]
fn eq(&self, other: &&'a str) -> bool {
*self == **other
}
}
impl<'a> PartialEq<HeaderName> for &'a str {
/// Performs a case-insensitive comparison of the string against the header
/// name
#[inline]
fn eq(&self, other: &HeaderName) -> bool {
*other == *self
}
}
impl fmt::Display for InvalidHeaderName {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.description().fmt(f)
}
}
impl Error for InvalidHeaderName {
fn description(&self) -> &str {
"invalid HTTP header name"
}
}
impl fmt::Display for InvalidHeaderNameBytes {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.0.fmt(f)
}
}
impl Error for InvalidHeaderNameBytes {
fn description(&self) -> &str {
self.0.description()
}
}
// ===== HdrName =====
impl<'a> HdrName<'a> {
fn custom(buf: &'a [u8], lower: bool) -> HdrName<'a> {
HdrName {
inner: Repr::Custom(MaybeLower {
buf: buf,
lower: lower,
}),
}
}
pub fn from_bytes<F, U>(hdr: &[u8], f: F) -> Result<U, InvalidHeaderName>
where F: FnOnce(HdrName) -> U,
{
let mut buf = unsafe { mem::uninitialized() };
let hdr = parse_hdr(hdr, &mut buf, &HEADER_CHARS)?;
Ok(f(hdr))
}
pub fn from_static<F, U>(hdr: &'static str, f: F) -> U
where F: FnOnce(HdrName) -> U,
{
let mut buf = unsafe { mem::uninitialized() };
let hdr = parse_hdr(hdr.as_bytes(), &mut buf, &HEADER_CHARS)
.expect("static str is invalid name");
f(hdr)
}
}
#[doc(hidden)]
impl<'a> From<HdrName<'a>> for HeaderName {
fn from(src: HdrName<'a>) -> HeaderName {
match src.inner {
Repr::Standard(s) => {
HeaderName {
inner: Repr::Standard(s),
}
}
Repr::Custom(maybe_lower) => {
if maybe_lower.lower {
let buf = Bytes::from(&maybe_lower.buf[..]);
let byte_str = unsafe { ByteStr::from_utf8_unchecked(buf) };
HeaderName {
inner: Repr::Custom(Custom(byte_str)),
}
} else {
use bytes::{BufMut};
let mut dst = BytesMut::with_capacity(maybe_lower.buf.len());
for b in maybe_lower.buf.iter() {
dst.put(HEADER_CHARS[*b as usize]);
}
let buf = unsafe { ByteStr::from_utf8_unchecked(dst.freeze()) };
HeaderName {
inner: Repr::Custom(Custom(buf)),
}
}
}
}
}
}
#[doc(hidden)]
impl<'a> PartialEq<HdrName<'a>> for HeaderName {
#[inline]
fn eq(&self, other: &HdrName<'a>) -> bool {
match self.inner {
Repr::Standard(a) => {
match other.inner {
Repr::Standard(b) => a == b,
_ => false,
}
}
Repr::Custom(Custom(ref a)) => {
match other.inner {
Repr::Custom(ref b) => {
if b.lower {
a.as_bytes() == b.buf
} else {
eq_ignore_ascii_case(a.as_bytes(), b.buf)
}
}
_ => false,
}
}
}
}
}
// ===== Custom =====
impl Hash for Custom {
#[inline]
fn hash<H: Hasher>(&self, hasher: &mut H) {
hasher.write(self.0.as_bytes())
}
}
// ===== MaybeLower =====
impl<'a> Hash for MaybeLower<'a> {
#[inline]
fn hash<H: Hasher>(&self, hasher: &mut H) {
if self.lower {
hasher.write(self.buf);
} else {
for &b in self.buf {
hasher.write(&[HEADER_CHARS[b as usize]]);
}
}
}
}
// Assumes that the left hand side is already lower case
#[inline]
fn eq_ignore_ascii_case(lower: &[u8], s: &[u8]) -> bool {
if lower.len() != s.len() {
return false;
}
lower.iter().zip(s).all(|(a, b)| {
*a == HEADER_CHARS[*b as usize]
})
}
#[test]
fn test_bounds() {
fn check_bounds<T: Sync + Send>() {}
check_bounds::<HeaderName>();
}
#[test]
fn test_parse_invalid_headers() {
for i in 0..128 {
let hdr = vec![1u8; i];
assert!(HeaderName::from_bytes(&hdr).is_err(), "{} invalid header chars did not fail", i);
}
}
#[test]
fn test_from_hdr_name() {
use self::StandardHeader::Vary;
let name = HeaderName::from(HdrName {
inner: Repr::Standard(Vary),
});
assert_eq!(name.inner, Repr::Standard(Vary));
let name = HeaderName::from(HdrName {
inner: Repr::Custom(MaybeLower {
buf: b"hello-world",
lower: true,
}),
});
assert_eq!(name.inner, Repr::Custom(Custom(ByteStr::from_static("hello-world"))));
let name = HeaderName::from(HdrName {
inner: Repr::Custom(MaybeLower {
buf: b"Hello-World",
lower: false,
}),
});
assert_eq!(name.inner, Repr::Custom(Custom(ByteStr::from_static("hello-world"))));
}
#[test]
fn test_eq_hdr_name() {
use self::StandardHeader::Vary;
let a = HeaderName { inner: Repr::Standard(Vary) };
let b = HdrName { inner: Repr::Standard(Vary) };
assert_eq!(a, b);
let a = HeaderName { inner: Repr::Custom(Custom(ByteStr::from_static("vaary"))) };
assert_ne!(a, b);
let b = HdrName { inner: Repr::Custom(MaybeLower {
buf: b"vaary",
lower: true,
})};
assert_eq!(a, b);
let b = HdrName { inner: Repr::Custom(MaybeLower {
buf: b"vaary",
lower: false,
})};
assert_eq!(a, b);
let b = HdrName { inner: Repr::Custom(MaybeLower {
buf: b"VAARY",
lower: false,
})};
assert_eq!(a, b);
let a = HeaderName { inner: Repr::Standard(Vary) };
assert_ne!(a, b);
}