fix mime() method

Reviewed-on: #27

Cargo.lock

@@ -70,7 +70,7 @@ checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
 
 [[package]]
 name = "eml-codec"
-version = "0.1.0"
+version = "0.1.2"
 dependencies = [
  "base64",
  "chrono",

Cargo.toml

@@ -1,9 +1,16 @@
 [package]
 name = "eml-codec"
-version = "0.1.0"
+version = "0.1.2"
 edition = "2021"
 license = "GPL-3.0-or-later"
-
+repository = "https://git.deuxfleurs.fr/Deuxfleurs/eml-codec"
+description = "Email enCOder DECoder in Rust. Support Internet Message Format and MIME (RFC 822, 5322, 2045, 2046, 2047, 2048, 2049)."
+documentation = "https://docs.rs/eml-codec"
+readme = "README.md"
+exclude = [
+    "doc/",
+    "resources/",
+]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [lib]
@@ -23,3 +30,4 @@ encoding_rs = "0.8"
 
 [dev-dependencies]
 walkdir = "2"
+

README.md

@@ -18,7 +18,7 @@ Content-Type: text/plain; charset=us-ascii
 This is the plain text body of the message. Note the blank line
 between the header information and the body of the message."#;
 
-let (_, email) = eml_codec::email(input).unwrap();
+let (_, email) = eml_codec::parse_message(input).unwrap();
 println!(
     "{} just sent you an email with subject \"{}\"",
     email.imf.from[0].to_string(),

examples/simple.rs

@@ -10,7 +10,7 @@ This is the plain text body of the message. Note the blank line
 between the header information and the body of the message."#;
 
     // if you are only interested in email metadata/headers
-    let (_, imf) = eml_codec::imf(input).unwrap();
+    let (_, imf) = eml_codec::parse_imf(input).unwrap();
     println!(
         "{} just sent you an email with subject \"{}\"",
         imf.from[0].to_string(),
@@ -18,7 +18,7 @@ between the header information and the body of the message."#;
     );
 
     // if you like to also parse the body/content
-    let (_, email) = eml_codec::email(input).unwrap();
+    let (_, email) = eml_codec::parse_message(input).unwrap();
     println!(
         "{} raw message is:\n{}",
         email.imf.from[0].to_string(),

src/header.rs

@@ -1,55 +1,62 @@
-
-use crate::text::misc_token::{unstructured, Unstructured};
-use crate::text::whitespace::{foldable_line, obs_crlf};
 use nom::{
     branch::alt,
-    bytes::complete::{tag, tag_no_case, take_while1},
+    bytes::complete::{tag, take_while1},
     character::complete::space0,
-    combinator::map,
-    multi::{fold_many0},
+    combinator::{into, recognize},
+    multi::many0,
     sequence::{pair, terminated, tuple},
     IResult,
 };
+use std::fmt;
 
-#[derive(Debug, PartialEq)]
-pub enum CompField<'a, T> {
-    Known(T),
-    Unknown(Kv<'a>),
-    Bad(&'a [u8]),
+use crate::text::misc_token::unstructured;
+use crate::text::whitespace::{foldable_line, obs_crlf};
+
+#[derive(PartialEq, Clone)]
+pub struct Kv2<'a>(pub &'a [u8], pub &'a [u8]);
+impl<'a> From<(&'a [u8], &'a [u8])> for Kv2<'a> {
+    fn from(pair: (&'a [u8], &'a [u8])) -> Self {
+        Self(pair.0, pair.1)
+    }
 }
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct Kv<'a>(pub &'a [u8], pub Unstructured<'a>);
-
-
-pub fn header<'a, T>(
-    fx: impl Fn(&'a [u8]) -> IResult<&'a [u8], T> + Copy,
-) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], (Vec::<T>, Vec::<Kv>, Vec<&'a [u8]>)> {
-    move |input| {
-            terminated(
-                fold_many0(
-                    alt((
-                        map(fx, CompField::Known),
-                        map(opt_field, |(k, v)| CompField::Unknown(Kv(k, v))),
-                        map(foldable_line, CompField::Bad),
-                    )),
-                    || (Vec::<T>::new(), Vec::<Kv>::new(), Vec::<&'a [u8]>::new()),
-                    |(mut known, mut unknown, mut bad), item| {
-                        match item {
-                            CompField::Known(v) => known.push(v),
-                            CompField::Unknown(v) => unknown.push(v),
-                            CompField::Bad(v) => bad.push(v),
-                        };
-                        (known, unknown, bad)
-                    }
-                ),
-                obs_crlf,
-            )(input)
+impl<'a> fmt::Debug for Kv2<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_tuple("header::Kv2")
+            .field(&String::from_utf8_lossy(self.0))
+            .field(&String::from_utf8_lossy(self.1))
+            .finish()
     }
 }
 
-pub fn field_name<'a>(name: &'static [u8]) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], &'a [u8]> {
-    move |input| terminated(tag_no_case(name), tuple((space0, tag(b":"), space0)))(input)
+#[derive(Debug, PartialEq, Clone)]
+pub enum Field<'a> {
+    Good(Kv2<'a>),
+    Bad(&'a [u8]),
+}
+impl<'a> From<Kv2<'a>> for Field<'a> {
+    fn from(kv: Kv2<'a>) -> Self {
+        Self::Good(kv)
+    }
+}
+impl<'a> From<&'a [u8]> for Field<'a> {
+    fn from(bad: &'a [u8]) -> Self {
+        Self::Bad(bad)
+    }
+}
+
+/// Parse headers as key/values
+pub fn header_kv(input: &[u8]) -> IResult<&[u8], Vec<Field>> {
+    terminated(
+        many0(alt((into(correct_field), into(foldable_line)))),
+        obs_crlf,
+    )(input)
+}
+
+pub fn field_any(input: &[u8]) -> IResult<&[u8], &[u8]> {
+    terminated(
+        take_while1(|c| (0x21..=0x7E).contains(&c) && c != 0x3A),
+        tuple((space0, tag(b":"), space0)),
+    )(input)
 }
 
 /// Optional field
@@ -61,15 +68,6 @@ pub fn field_name<'a>(name: &'static [u8]) -> impl Fn(&'a [u8]) -> IResult<&'a [
 ///                %d59-126           ;  characters not including
 ///                                   ;  ":".
 /// ```
-pub fn opt_field(input: &[u8]) -> IResult<&[u8], (&[u8], Unstructured)> {
-    terminated(
-        pair(
-            terminated(
-                take_while1(|c| (0x21..=0x7E).contains(&c) && c != 0x3A),
-                tuple((space0, tag(b":"), space0)),
-            ),
-            unstructured,
-        ),
-        obs_crlf,
-    )(input)
+pub fn correct_field(input: &[u8]) -> IResult<&[u8], Kv2> {
+    terminated(into(pair(field_any, recognize(unstructured))), obs_crlf)(input)
 }

src/imf/field.rs

@@ -1,21 +1,14 @@
 use chrono::{DateTime, FixedOffset};
-use nom::{
-    branch::alt,
-    combinator::map,
-    sequence::{preceded, terminated},
-    IResult,
-};
+use nom::combinator::map;
 
-use crate::header::{field_name, header};
+use crate::header;
 use crate::imf::address::{address_list, mailbox_list, nullable_address_list, AddressList};
 use crate::imf::datetime::section as date;
 use crate::imf::identification::{msg_id, msg_list, MessageID, MessageIDList};
 use crate::imf::mailbox::{mailbox, AddrSpec, MailboxList, MailboxRef};
 use crate::imf::mime::{version, Version};
 use crate::imf::trace::{received_log, return_path, ReceivedLog};
-use crate::imf::Imf;
 use crate::text::misc_token::{phrase_list, unstructured, PhraseList, Unstructured};
-use crate::text::whitespace::obs_crlf;
 
 #[derive(Debug, PartialEq)]
 pub enum Field<'a> {
@@ -49,94 +42,34 @@ pub enum Field<'a> {
 
     MIMEVersion(Version),
 }
-
-pub fn field(input: &[u8]) -> IResult<&[u8], Field> {
-    terminated(
-        alt((
-            preceded(field_name(b"date"), map(date, Field::Date)),
-            preceded(field_name(b"from"), map(mailbox_list, Field::From)),
-            preceded(field_name(b"sender"), map(mailbox, Field::Sender)),
-            preceded(field_name(b"reply-to"), map(address_list, Field::ReplyTo)),
-            preceded(field_name(b"to"), map(address_list, Field::To)),
-            preceded(field_name(b"cc"), map(address_list, Field::Cc)),
-            preceded(field_name(b"bcc"), map(nullable_address_list, Field::Bcc)),
-            preceded(field_name(b"message-id"), map(msg_id, Field::MessageID)),
-            preceded(field_name(b"in-reply-to"), map(msg_list, Field::InReplyTo)),
-            preceded(field_name(b"references"), map(msg_list, Field::References)),
-            preceded(field_name(b"subject"), map(unstructured, Field::Subject)),
-            preceded(field_name(b"comments"), map(unstructured, Field::Comments)),
-            preceded(field_name(b"keywords"), map(phrase_list, Field::Keywords)),
-            preceded(
-                field_name(b"return-path"),
-                map(return_path, Field::ReturnPath),
-            ),
-            preceded(field_name(b"received"), map(received_log, Field::Received)),
-            preceded(
-                field_name(b"mime-version"),
-                map(version, Field::MIMEVersion),
-            ),
-        )),
-        obs_crlf,
-    )(input)
-}
-
-pub fn imf(input: &[u8]) -> IResult<&[u8], Imf> {
-    map(header(field), |(known, unknown, bad)| { 
-        let mut imf = Imf::from_iter(known);
-        imf.header_ext = unknown;
-        imf.header_bad = bad;
-        imf
-    })(input)
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::imf::address::*;
-    use crate::imf::mailbox::*;
-    use crate::text::misc_token::*;
-    use chrono::{FixedOffset, TimeZone};
-
-    #[test]
-    fn test_header() {
-        let fullmail = b"Date: 7 Mar 2023 08:00:00 +0200
-From: someone@example.com
-To: someone_else@example.com
-Subject: An RFC 822 formatted message
-
-This is the plain text body of the message. Note the blank line
-between the header information and the body of the message.";
-
-        assert_eq!(
-            imf(fullmail),
-            Ok((
-                &b"This is the plain text body of the message. Note the blank line\nbetween the header information and the body of the message."[..],
-                Imf {
-                    date: Some(FixedOffset::east_opt(2 * 3600).unwrap().with_ymd_and_hms(2023, 3, 7, 8, 0, 0).unwrap()),
-                    from: vec![MailboxRef {
-                        name: None,
-                        addrspec: AddrSpec {
-                            local_part: LocalPart(vec![LocalPartToken::Word(Word::Atom(&b"someone"[..]))]),
-                            domain: Domain::Atoms(vec![&b"example"[..], &b"com"[..]]),
-                        }
-                    }],
-                    to: vec![AddressRef::Single(MailboxRef {
-                        name: None,
-                        addrspec: AddrSpec {
-                            local_part: LocalPart(vec![LocalPartToken::Word(Word::Atom(&b"someone_else"[..]))]),
-                            domain: Domain::Atoms(vec![&b"example"[..], &b"com"[..]]),
-                        }
-                    })],
-                    subject: Some(Unstructured(vec![
-                        UnstrToken::Plain(&b"An"[..]),
-                        UnstrToken::Plain(&b"RFC"[..]),
-                        UnstrToken::Plain(&b"822"[..]), 
-                        UnstrToken::Plain(&b"formatted"[..]), 
-                        UnstrToken::Plain(&b"message"[..]),
-                    ])),
-                    ..Imf::default()
+impl<'a> TryFrom<&header::Field<'a>> for Field<'a> {
+    type Error = ();
+    fn try_from(f: &header::Field<'a>) -> Result<Self, Self::Error> {
+        let content = match f {
+            header::Field::Good(header::Kv2(key, value)) => {
+                match key.to_ascii_lowercase().as_slice() {
+                    b"date" => map(date, Field::Date)(value),
+                    b"from" => map(mailbox_list, Field::From)(value),
+                    b"sender" => map(mailbox, Field::Sender)(value),
+                    b"reply-to" => map(address_list, Field::ReplyTo)(value),
+                    b"to" => map(address_list, Field::To)(value),
+                    b"cc" => map(address_list, Field::Cc)(value),
+                    b"bcc" => map(nullable_address_list, Field::Bcc)(value),
+                    b"message-id" => map(msg_id, Field::MessageID)(value),
+                    b"in-reply-to" => map(msg_list, Field::InReplyTo)(value),
+                    b"references" => map(msg_list, Field::References)(value),
+                    b"subject" => map(unstructured, Field::Subject)(value),
+                    b"comments" => map(unstructured, Field::Comments)(value),
+                    b"keywords" => map(phrase_list, Field::Keywords)(value),
+                    b"return-path" => map(return_path, Field::ReturnPath)(value),
+                    b"received" => map(received_log, Field::Received)(value),
+                    b"mime-version" => map(version, Field::MIMEVersion)(value),
+                    _ => return Err(()),
                 }
-            )),
-        )
+            }
+            _ => return Err(()),
+        };
+
+        content.map(|(_, content)| content).or(Err(()))
     }
 }

src/imf/mod.rs

@@ -1,5 +1,4 @@
 /// Parse and represent IMF (Internet Message Format) headers (RFC822, RFC5322)
-
 pub mod address;
 pub mod datetime;
 pub mod field;
@@ -8,13 +7,15 @@ pub mod mailbox;
 pub mod mime;
 pub mod trace;
 
+use nom::{combinator::map, IResult};
+
+use crate::header;
 use crate::imf::address::AddressRef;
 use crate::imf::field::Field;
 use crate::imf::identification::MessageID;
 use crate::imf::mailbox::{AddrSpec, MailboxRef};
 use crate::imf::mime::Version;
 use crate::imf::trace::ReceivedLog;
-use crate::header;
 use crate::text::misc_token::{PhraseList, Unstructured};
 use chrono::{DateTime, FixedOffset};
 
@@ -50,19 +51,6 @@ pub struct Imf<'a> {
 
     // MIME
     pub mime_version: Option<Version>,
-
-    // Junk
-    pub header_ext: Vec<header::Kv<'a>>,
-    pub header_bad: Vec<&'a [u8]>,
-}
-
-impl<'a> Imf<'a> {
-    pub fn with_opt(mut self, opt: Vec<header::Kv<'a>>) -> Self {
-        self.header_ext = opt; self
-    }
-    pub fn with_bad(mut self, bad: Vec<&'a [u8]>) -> Self {
-        self.header_bad = bad; self
-    }
 }
 
 //@FIXME min and max limits are not enforced,
@@ -92,3 +80,65 @@ impl<'a> FromIterator<Field<'a>> for Imf<'a> {
         })
     }
 }
+
+pub fn imf(input: &[u8]) -> IResult<&[u8], Imf> {
+    map(header::header_kv, |fields| {
+        fields
+            .iter()
+            .flat_map(Field::try_from)
+            .into_iter()
+            .collect::<Imf>()
+    })(input)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::imf::address::*;
+    use crate::imf::mailbox::*;
+    use crate::text::misc_token::*;
+    use chrono::{FixedOffset, TimeZone};
+
+    #[test]
+    fn test_header() {
+        let fullmail = b"Date: 7 Mar 2023 08:00:00 +0200
+From: someone@example.com
+To: someone_else@example.com
+Subject: An RFC 822 formatted message
+
+This is the plain text body of the message. Note the blank line
+between the header information and the body of the message.";
+
+        assert_eq!(
+            imf(fullmail),
+            Ok((
+                &b"This is the plain text body of the message. Note the blank line\nbetween the header information and the body of the message."[..],
+                Imf {
+                    date: Some(FixedOffset::east_opt(2 * 3600).unwrap().with_ymd_and_hms(2023, 3, 7, 8, 0, 0).unwrap()),
+                    from: vec![MailboxRef {
+                        name: None,
+                        addrspec: AddrSpec {
+                            local_part: LocalPart(vec![LocalPartToken::Word(Word::Atom(&b"someone"[..]))]),
+                            domain: Domain::Atoms(vec![&b"example"[..], &b"com"[..]]),
+                        }
+                    }],
+                    to: vec![AddressRef::Single(MailboxRef {
+                        name: None,
+                        addrspec: AddrSpec {
+                            local_part: LocalPart(vec![LocalPartToken::Word(Word::Atom(&b"someone_else"[..]))]),
+                            domain: Domain::Atoms(vec![&b"example"[..], &b"com"[..]]),
+                        }
+                    })],
+                    subject: Some(Unstructured(vec![
+                        UnstrToken::Plain(&b"An"[..]),
+                        UnstrToken::Plain(&b"RFC"[..]),
+                        UnstrToken::Plain(&b"822"[..]), 
+                        UnstrToken::Plain(&b"formatted"[..]), 
+                        UnstrToken::Plain(&b"message"[..]),
+                    ])),
+                    ..Imf::default()
+                }
+            )),
+        )
+    }
+}

src/lib.rs

@@ -15,7 +15,10 @@ pub mod header;
 /// Low-level email-specific text-based representation for data
 pub mod text;
 
-use nom::IResult;
+/// Manipulate buffer of bytes
+mod pointers;
+
+use nom::{combinator::into, IResult};
 
 /// Parse a whole email including its (MIME) body
 ///
@@ -34,7 +37,7 @@ use nom::IResult;
 /// * `msg` - The parsed message
 ///
 /// # Examples
-/// 
+///
 /// ```
 /// let input = br#"Date: 7 Mar 2023 08:00:00 +0200
 /// From: deuxfleurs@example.com
@@ -46,15 +49,17 @@ use nom::IResult;
 /// This is the plain text body of the message. Note the blank line
 /// between the header information and the body of the message."#;
 ///
-/// let (_, email) = eml_codec::email(input).unwrap();
+/// let (_, email) = eml_codec::parse_message(input).unwrap();
 /// println!(
 ///     "{} raw message is:\n{}",
 ///     email.imf.from[0].to_string(),
 ///     String::from_utf8_lossy(email.child.as_text().unwrap().body),
 /// );
 /// ```
-pub fn email(input: &[u8]) -> IResult<&[u8], part::composite::Message> {
-    part::composite::message(mime::MIME::<mime::r#type::Message>::default())(input)
+pub fn parse_message(input: &[u8]) -> IResult<&[u8], part::composite::Message> {
+    into(part::composite::message(mime::MIME::<
+        mime::r#type::DeductibleMessage,
+    >::default()))(input)
 }
 
 /// Only extract the headers of the email that are part of the Internet Message Format spec
@@ -87,13 +92,13 @@ pub fn email(input: &[u8]) -> IResult<&[u8], part::composite::Message> {
 /// This is the plain text body of the message. Note the blank line
 /// between the header information and the body of the message."#;
 ///
-/// let (_, imf) = eml_codec::imf(input).unwrap();
+/// let (_, imf) = eml_codec::parse_imf(input).unwrap();
 /// println!(
 ///     "{} just sent you an email with subject \"{}\"",
 ///     imf.from[0].to_string(),
 ///     imf.subject.unwrap().to_string(),
 /// );
 /// ```
-pub fn imf(input: &[u8]) -> IResult<&[u8], imf::Imf> {
-    imf::field::imf(input)
+pub fn parse_imf(input: &[u8]) -> IResult<&[u8], imf::Imf> {
+    imf::imf(input)
 }

src/mime/charset.rs

@@ -77,6 +77,12 @@ impl<'a> From<&'a [u8]> for EmailCharset {
     }
 }
 
+impl ToString for EmailCharset {
+    fn to_string(&self) -> String {
+        self.as_str().into()
+    }
+}
+
 impl EmailCharset {
     pub fn as_str(&self) -> &'static str {
         use EmailCharset::*;

src/mime/field.rs

@@ -1,16 +1,10 @@
-use nom::{
-    branch::alt,
-    combinator::map,
-    sequence::{preceded, terminated},
-    IResult,
-};
+use nom::combinator::map;
 
-use crate::header::{field_name};
+use crate::header;
 use crate::imf::identification::{msg_id, MessageID};
 use crate::mime::mechanism::{mechanism, Mechanism};
 use crate::mime::r#type::{naive_type, NaiveType};
 use crate::text::misc_token::{unstructured, Unstructured};
-use crate::text::whitespace::obs_crlf;
 
 #[derive(Debug, PartialEq)]
 pub enum Content<'a> {
@@ -47,38 +41,38 @@ impl<'a> Content<'a> {
     }
 }
 
-/*
-pub fn to_mime<'a, T: WithDefaultType>(list: Vec<Content<'a>>) -> AnyMIMEWithDefault<'a, T> {
-    list.into_iter().collect::<AnyMIMEWithDefault<T>>()
-}*/
+impl<'a> TryFrom<&header::Field<'a>> for Content<'a> {
+    type Error = ();
+    fn try_from(f: &header::Field<'a>) -> Result<Self, Self::Error> {
+        let content = match f {
+            header::Field::Good(header::Kv2(key, value)) => match key
+                .to_ascii_lowercase()
+                .as_slice()
+            {
+                b"content-type" => map(naive_type, Content::Type)(value),
+                b"content-transfer-encoding" => map(mechanism, Content::TransferEncoding)(value),
+                b"content-id" => map(msg_id, Content::ID)(value),
+                b"content-description" => map(unstructured, Content::Description)(value),
+                _ => return Err(()),
+            },
+            _ => return Err(()),
+        };
 
-pub fn content(input: &[u8]) -> IResult<&[u8], Content> {
-    terminated(
-        alt((
-            preceded(field_name(b"content-type"), map(naive_type, Content::Type)),
-            preceded(
-                field_name(b"content-transfer-encoding"),
-                map(mechanism, Content::TransferEncoding),
-            ),
-            preceded(field_name(b"content-id"), map(msg_id, Content::ID)),
-            preceded(
-                field_name(b"content-description"),
-                map(unstructured, Content::Description),
-            ),
-        )),
-        obs_crlf,
-    )(input)
+        //@TODO check that the full value is parsed, otherwise maybe log an error ?!
+        content.map(|(_, content)| content).or(Err(()))
+    }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::header::{header};
-    use crate::mime::charset::EmailCharset;
+    use crate::header;
+    //use crate::mime::charset::EmailCharset;
     use crate::mime::r#type::*;
     use crate::text::misc_token::MIMEWord;
     use crate::text::quoted::QuotedString;
 
+    /*
     #[test]
     fn test_content_type() {
         let (rest, content) =
@@ -88,15 +82,15 @@ mod tests {
         if let Content::Type(nt) = content {
             assert_eq!(
                 nt.to_type(),
-                AnyType::Text(Text {
-                    charset: EmailCharset::UTF_8,
+                AnyType::Text(Deductible::Explicit(Text {
+                    charset: Deductible::Explicit(EmailCharset::UTF_8),
                     subtype: TextSubtype::Plain,
-                }),
+                })),
             );
         } else {
             panic!("Expected Content::Type, got {:?}", content);
         }
-    }
+    }*/
 
     #[test]
     fn test_header() {
@@ -116,7 +110,10 @@ This is a multipart message.
         .as_bytes();
 
         assert_eq!(
-            map(header(content), |(k, _, _)| k)(fullmail),
+            map(header::header_kv, |k| k
+                .iter()
+                .flat_map(Content::try_from)
+                .collect())(fullmail),
             Ok((
                 &b"This is a multipart message.\n\n"[..],
                 vec![

src/mime/mechanism.rs

@@ -18,6 +18,20 @@ pub enum Mechanism<'a> {
     Base64,
     Other(&'a [u8]),
 }
+impl<'a> ToString for Mechanism<'a> {
+    fn to_string(&self) -> String {
+        use Mechanism::*;
+        let buf: &[u8] = match self {
+            _7Bit => b"7bit",
+            _8Bit => b"8bit",
+            Binary => b"binary",
+            QuotedPrintable => b"quoted-printable",
+            Base64 => b"base64",
+            Other(x) => x,
+        };
+        String::from_utf8_lossy(buf).to_string()
+    }
+}
 
 pub fn mechanism(input: &[u8]) -> IResult<&[u8], Mechanism> {
     use Mechanism::*;

src/mime/mod.rs

@@ -1,4 +1,4 @@
-/// Parsed and represent an email character set 
+/// Parsed and represent an email character set
 pub mod charset;
 
 /// MIME specific headers
@@ -10,33 +10,34 @@ pub mod mechanism;
 /// Content-Type representation
 pub mod r#type;
 
+use std::fmt;
 use std::marker::PhantomData;
 
+use crate::header;
 use crate::imf::identification::MessageID;
 use crate::mime::field::Content;
 use crate::mime::mechanism::Mechanism;
 use crate::mime::r#type::{AnyType, NaiveType};
-use crate::header;
 use crate::text::misc_token::Unstructured; //Multipart, Message, Text, Binary};
 
 #[derive(Debug, PartialEq, Clone)]
 pub struct MIME<'a, T> {
-    pub interpreted: T, 
-    pub parsed: NaiveMIME<'a>
+    pub interpreted_type: T,
+    pub fields: NaiveMIME<'a>,
 }
-impl<'a> Default for MIME<'a, r#type::Text> {
+impl<'a> Default for MIME<'a, r#type::DeductibleText> {
     fn default() -> Self {
         Self {
-            interpreted: r#type::Text::default(),
-            parsed: NaiveMIME::default(),
+            interpreted_type: r#type::DeductibleText::default(),
+            fields: NaiveMIME::default(),
         }
     }
 }
-impl<'a> Default for MIME<'a, r#type::Message> {
+impl<'a> Default for MIME<'a, r#type::DeductibleMessage> {
     fn default() -> Self {
         Self {
-            interpreted: r#type::Message::default(),
-            parsed: NaiveMIME::default(),
+            interpreted_type: r#type::DeductibleMessage::default(),
+            fields: NaiveMIME::default(),
         }
     }
 }
@@ -44,10 +45,20 @@ impl<'a> Default for MIME<'a, r#type::Message> {
 #[derive(Debug, PartialEq, Clone)]
 pub enum AnyMIME<'a> {
     Mult(MIME<'a, r#type::Multipart>),
-    Msg(MIME<'a, r#type::Message>),
-    Txt(MIME<'a, r#type::Text>),
+    Msg(MIME<'a, r#type::DeductibleMessage>),
+    Txt(MIME<'a, r#type::DeductibleText>),
     Bin(MIME<'a, r#type::Binary>),
 }
+impl<'a> AnyMIME<'a> {
+    pub fn fields(&self) -> &NaiveMIME<'a> {
+        match self {
+            Self::Mult(v) => &v.fields,
+            Self::Msg(v) => &v.fields,
+            Self::Txt(v) => &v.fields,
+            Self::Bin(v) => &v.fields,
+        }
+    }
+}
 
 impl<'a, T: WithDefaultType> From<AnyMIMEWithDefault<'a, T>> for AnyMIME<'a> {
     fn from(a: AnyMIMEWithDefault<'a, T>) -> Self {
@@ -55,21 +66,32 @@ impl<'a, T: WithDefaultType> From<AnyMIMEWithDefault<'a, T>> for AnyMIME<'a> {
     }
 }
 
-#[derive(Debug, PartialEq, Default, Clone)]
+#[derive(PartialEq, Default, Clone)]
 pub struct NaiveMIME<'a> {
     pub ctype: Option<NaiveType<'a>>,
     pub transfer_encoding: Mechanism<'a>,
     pub id: Option<MessageID<'a>>,
     pub description: Option<Unstructured<'a>>,
-    pub header_ext: Vec<header::Kv<'a>>,
-    pub header_bad: Vec<&'a [u8]>,
+    pub kv: Vec<header::Field<'a>>,
+    pub raw: &'a [u8],
+}
+impl<'a> fmt::Debug for NaiveMIME<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("NaiveMime")
+            .field("ctype", &self.ctype)
+            .field("transfer_encoding", &self.transfer_encoding)
+            .field("id", &self.id)
+            .field("description", &self.description)
+            .field("kv", &self.kv)
+            .field("raw", &String::from_utf8_lossy(self.raw))
+            .finish()
+    }
 }
 
 impl<'a> FromIterator<Content<'a>> for NaiveMIME<'a> {
     fn from_iter<I: IntoIterator<Item = Content<'a>>>(it: I) -> Self {
-        it.into_iter().fold(
-            NaiveMIME::default(),
-            |mut section, field| {
+        it.into_iter()
+            .fold(NaiveMIME::default(), |mut section, field| {
                 match field {
                     Content::Type(v) => section.ctype = Some(v),
                     Content::TransferEncoding(v) => section.transfer_encoding = v,
@@ -77,25 +99,29 @@ impl<'a> FromIterator<Content<'a>> for NaiveMIME<'a> {
                     Content::Description(v) => section.description = Some(v),
                 };
                 section
-            },
-        )
+            })
     }
 }
 
 impl<'a> NaiveMIME<'a> {
-    pub fn with_opt(mut self, opt: Vec<header::Kv<'a>>) -> Self {
-        self.header_ext = opt; self
+    pub fn with_kv(mut self, fields: Vec<header::Field<'a>>) -> Self {
+        self.kv = fields;
+        self
     }
-    pub fn with_bad(mut self, bad: Vec<&'a [u8]>) -> Self {
-        self.header_bad = bad; self
+    pub fn with_raw(mut self, raw: &'a [u8]) -> Self {
+        self.raw = raw;
+        self
     }
     pub fn to_interpreted<T: WithDefaultType>(self) -> AnyMIME<'a> {
-       self.ctype.as_ref().map(|c| c.to_type()).unwrap_or(T::default_type()).to_mime(self).into()
+        self.ctype
+            .as_ref()
+            .map(|c| c.to_type())
+            .unwrap_or(T::default_type())
+            .to_mime(self)
+            .into()
     }
 }
 
-
-
 pub trait WithDefaultType {
     fn default_type() -> AnyType;
 }
@@ -103,13 +129,13 @@ pub trait WithDefaultType {
 pub struct WithGenericDefault {}
 impl WithDefaultType for WithGenericDefault {
     fn default_type() -> AnyType {
-        AnyType::Text(r#type::Text::default())
+        AnyType::Text(r#type::DeductibleText::default())
     }
 }
 pub struct WithDigestDefault {}
 impl WithDefaultType for WithDigestDefault {
     fn default_type() -> AnyType {
-        AnyType::Message(r#type::Message::default())
+        AnyType::Message(r#type::DeductibleMessage::default())
     }
 }
 

src/mime/type.rs

@@ -5,19 +5,29 @@ use nom::{
     sequence::{preceded, terminated, tuple},
     IResult,
 };
+use std::fmt;
 
 use crate::mime::charset::EmailCharset;
+use crate::mime::{AnyMIME, NaiveMIME, MIME};
 use crate::text::misc_token::{mime_word, MIMEWord};
 use crate::text::words::mime_atom;
-use crate::mime::{AnyMIME, MIME, NaiveMIME};
 
 // --------- NAIVE TYPE
-#[derive(Debug, PartialEq, Clone)]
+#[derive(PartialEq, Clone)]
 pub struct NaiveType<'a> {
     pub main: &'a [u8],
     pub sub: &'a [u8],
     pub params: Vec<Parameter<'a>>,
 }
+impl<'a> fmt::Debug for NaiveType<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("mime::NaiveType")
+            .field("main", &String::from_utf8_lossy(self.main))
+            .field("sub", &String::from_utf8_lossy(self.sub))
+            .field("params", &self.params)
+            .finish()
+    }
+}
 impl<'a> NaiveType<'a> {
     pub fn to_type(&self) -> AnyType {
         self.into()
@@ -30,11 +40,20 @@ pub fn naive_type(input: &[u8]) -> IResult<&[u8], NaiveType> {
     )(input)
 }
 
-#[derive(Debug, PartialEq, Clone)]
+#[derive(PartialEq, Clone)]
 pub struct Parameter<'a> {
     pub name: &'a [u8],
     pub value: MIMEWord<'a>,
 }
+impl<'a> fmt::Debug for Parameter<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("mime::Parameter")
+            .field("name", &String::from_utf8_lossy(self.name))
+            .field("value", &self.value)
+            .finish()
+    }
+}
+
 pub fn parameter(input: &[u8]) -> IResult<&[u8], Parameter> {
     map(
         tuple((mime_atom, tag(b"="), mime_word)),
@@ -51,10 +70,10 @@ pub fn parameter_list(input: &[u8]) -> IResult<&[u8], Vec<Parameter>> {
 pub enum AnyType {
     // Composite types
     Multipart(Multipart),
-    Message(Message),
+    Message(Deductible<Message>),
 
     // Discrete types
-    Text(Text),
+    Text(Deductible<Text>),
     Binary(Binary),
 }
 
@@ -63,30 +82,60 @@ impl<'a> From<&'a NaiveType<'a>> for AnyType {
         match nt.main.to_ascii_lowercase().as_slice() {
             b"multipart" => Multipart::try_from(nt)
                 .map(Self::Multipart)
-                .unwrap_or(Self::Text(Text::default())),
-            b"message" => Self::Message(Message::from(nt)),
-            b"text" => Self::Text(Text::from(nt)),
+                .unwrap_or(Self::Text(DeductibleText::default())),
+            b"message" => Self::Message(DeductibleMessage::Explicit(Message::from(nt))),
+            b"text" => Self::Text(DeductibleText::Explicit(Text::from(nt))),
             _ => Self::Binary(Binary::default()),
         }
     }
 }
 
 impl<'a> AnyType {
-    pub fn to_mime(self, parsed: NaiveMIME<'a>) -> AnyMIME<'a> {
-         match self {
-            Self::Multipart(interpreted) => AnyMIME::Mult(MIME::<Multipart> { interpreted, parsed }),
-            Self::Message(interpreted) => AnyMIME::Msg(MIME::<Message> { interpreted, parsed }),
-            Self::Text(interpreted) => AnyMIME::Txt(MIME::<Text> { interpreted, parsed }),
-            Self::Binary(interpreted) => AnyMIME::Bin(MIME::<Binary> { interpreted, parsed }),
-        }       
+    pub fn to_mime(self, fields: NaiveMIME<'a>) -> AnyMIME<'a> {
+        match self {
+            Self::Multipart(interpreted_type) => AnyMIME::Mult(MIME::<Multipart> {
+                interpreted_type,
+                fields,
+            }),
+            Self::Message(interpreted_type) => AnyMIME::Msg(MIME::<DeductibleMessage> {
+                interpreted_type,
+                fields,
+            }),
+            Self::Text(interpreted_type) => AnyMIME::Txt(MIME::<DeductibleText> {
+                interpreted_type,
+                fields,
+            }),
+            Self::Binary(interpreted_type) => AnyMIME::Bin(MIME::<Binary> {
+                interpreted_type,
+                fields,
+            }),
+        }
     }
 }
 
+#[derive(Debug, PartialEq, Clone)]
+pub enum Deductible<T: Default> {
+    Inferred(T),
+    Explicit(T),
+}
+impl<T: Default> Default for Deductible<T> {
+    fn default() -> Self {
+        Self::Inferred(T::default())
+    }
+}
+
+// REAL PARTS
+
 #[derive(Debug, PartialEq, Clone)]
 pub struct Multipart {
     pub subtype: MultipartSubtype,
     pub boundary: String,
 }
+impl Multipart {
+    pub fn main_type(&self) -> String {
+        "multipart".into()
+    }
+}
 impl<'a> TryFrom<&'a NaiveType<'a>> for Multipart {
     type Error = ();
 
@@ -111,6 +160,19 @@ pub enum MultipartSubtype {
     Report,
     Unknown,
 }
+impl ToString for MultipartSubtype {
+    fn to_string(&self) -> String {
+        match self {
+            Self::Alternative => "alternative",
+            Self::Mixed => "mixed",
+            Self::Digest => "digest",
+            Self::Parallel => "parallel",
+            Self::Report => "report",
+            Self::Unknown => "mixed",
+        }
+        .into()
+    }
+}
 impl<'a> From<&NaiveType<'a>> for MultipartSubtype {
     fn from(nt: &NaiveType<'a>) -> Self {
         match nt.sub.to_ascii_lowercase().as_slice() {
@@ -125,28 +187,61 @@ impl<'a> From<&NaiveType<'a>> for MultipartSubtype {
 }
 
 #[derive(Debug, PartialEq, Default, Clone)]
-pub enum Message {
+pub enum MessageSubtype {
     #[default]
     RFC822,
     Partial,
     External,
     Unknown,
 }
+impl ToString for MessageSubtype {
+    fn to_string(&self) -> String {
+        match self {
+            Self::RFC822 => "rfc822",
+            Self::Partial => "partial",
+            Self::External => "external",
+            Self::Unknown => "rfc822",
+        }
+        .into()
+    }
+}
+
+pub type DeductibleMessage = Deductible<Message>;
+#[derive(Debug, PartialEq, Default, Clone)]
+pub struct Message {
+    pub subtype: MessageSubtype,
+}
 impl<'a> From<&NaiveType<'a>> for Message {
     fn from(nt: &NaiveType<'a>) -> Self {
         match nt.sub.to_ascii_lowercase().as_slice() {
-            b"rfc822" => Self::RFC822,
-            b"partial" => Self::Partial,
-            b"external" => Self::External,
-            _ => Self::Unknown,
+            b"rfc822" => Self {
+                subtype: MessageSubtype::RFC822,
+            },
+            b"partial" => Self {
+                subtype: MessageSubtype::Partial,
+            },
+            b"external" => Self {
+                subtype: MessageSubtype::External,
+            },
+            _ => Self {
+                subtype: MessageSubtype::Unknown,
+            },
+        }
+    }
+}
+impl From<Deductible<Message>> for Message {
+    fn from(d: Deductible<Message>) -> Self {
+        match d {
+            Deductible::Inferred(t) | Deductible::Explicit(t) => t,
         }
     }
 }
 
+pub type DeductibleText = Deductible<Text>;
 #[derive(Debug, PartialEq, Default, Clone)]
 pub struct Text {
     pub subtype: TextSubtype,
-    pub charset: EmailCharset,
+    pub charset: Deductible<EmailCharset>,
 }
 impl<'a> From<&NaiveType<'a>> for Text {
     fn from(nt: &NaiveType<'a>) -> Self {
@@ -156,8 +251,15 @@ impl<'a> From<&NaiveType<'a>> for Text {
                 .params
                 .iter()
                 .find(|x| x.name.to_ascii_lowercase().as_slice() == b"charset")
-                .map(|x| EmailCharset::from(x.value.to_string().as_bytes()))
-                .unwrap_or(EmailCharset::US_ASCII),
+                .map(|x| Deductible::Explicit(EmailCharset::from(x.value.to_string().as_bytes())))
+                .unwrap_or(Deductible::Inferred(EmailCharset::US_ASCII)),
+        }
+    }
+}
+impl From<Deductible<Text>> for Text {
+    fn from(d: Deductible<Text>) -> Self {
+        match d {
+            Deductible::Inferred(t) | Deductible::Explicit(t) => t,
         }
     }
 }
@@ -169,6 +271,15 @@ pub enum TextSubtype {
     Html,
     Unknown,
 }
+impl ToString for TextSubtype {
+    fn to_string(&self) -> String {
+        match self {
+            Self::Plain | Self::Unknown => "plain",
+            Self::Html => "html",
+        }
+        .into()
+    }
+}
 impl<'a> From<&NaiveType<'a>> for TextSubtype {
     fn from(nt: &NaiveType<'a>) -> Self {
         match nt.sub.to_ascii_lowercase().as_slice() {
@@ -186,6 +297,7 @@ pub struct Binary {}
 mod tests {
     use super::*;
     use crate::mime::charset::EmailCharset;
+    use crate::mime::r#type::Deductible;
     use crate::text::quoted::QuotedString;
 
     #[test]
@@ -219,10 +331,10 @@ mod tests {
 
         assert_eq!(
             nt.to_type(),
-            AnyType::Text(Text {
-                charset: EmailCharset::UTF_8,
+            AnyType::Text(Deductible::Explicit(Text {
+                charset: Deductible::Explicit(EmailCharset::UTF_8),
                 subtype: TextSubtype::Plain,
-            })
+            }))
         );
     }
 
@@ -244,7 +356,12 @@ mod tests {
         let (rest, nt) = naive_type(b"message/rfc822").unwrap();
         assert_eq!(rest, &[]);
 
-        assert_eq!(nt.to_type(), AnyType::Message(Message::RFC822),);
+        assert_eq!(
+            nt.to_type(),
+            AnyType::Message(Deductible::Explicit(Message {
+                subtype: MessageSubtype::RFC822
+            }))
+        );
     }
 
     #[test]

src/parse.rs

@@ -8,7 +8,7 @@ fn main() {
     let mut rawmail = Vec::new();
     io::stdin().lock().read_to_end(&mut rawmail).unwrap();
 
-    let (_, eml) = eml_codec::email(&rawmail).unwrap();
+    let (_, eml) = eml_codec::parse_message(&rawmail).unwrap();
     println!("{:#?}", eml);
     assert!(eml.imf.date.is_some());
     assert!(!eml.imf.from.is_empty());

src/part/composite.rs

@@ -1,23 +1,49 @@
 use nom::IResult;
+use std::fmt;
 
-use crate::header::{header, self};
+use crate::header;
 use crate::imf;
 use crate::mime;
-use crate::part::{self, AnyPart, field::MixedField};
+use crate::part::{self, AnyPart};
+use crate::pointers;
 use crate::text::boundary::{boundary, Delimiter};
 
 //--- Multipart
-#[derive(Debug, PartialEq)]
+#[derive(PartialEq)]
 pub struct Multipart<'a> {
-    pub interpreted: mime::MIME<'a, mime::r#type::Multipart>,
+    pub mime: mime::MIME<'a, mime::r#type::Multipart>,
     pub children: Vec<AnyPart<'a>>,
-    pub preamble: &'a [u8],
-    pub epilogue: &'a [u8],
+    pub raw_part_inner: &'a [u8],
+    pub raw_part_outer: &'a [u8],
+}
+impl<'a> fmt::Debug for Multipart<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("part::Multipart")
+            .field("mime", &self.mime)
+            .field("children", &self.children)
+            .field(
+                "raw_part_inner",
+                &String::from_utf8_lossy(self.raw_part_inner),
+            )
+            .field(
+                "raw_part_outer",
+                &String::from_utf8_lossy(self.raw_part_outer),
+            )
+            .finish()
+    }
 }
 impl<'a> Multipart<'a> {
-    pub fn with_epilogue(mut self, e: &'a [u8]) -> Self {
-        self.epilogue = e;
-        self
+    pub fn preamble(&self) -> &'a [u8] {
+        pointers::parsed(self.raw_part_outer, self.raw_part_inner)
+    }
+    pub fn epilogue(&self) -> &'a [u8] {
+        pointers::rest(self.raw_part_outer, self.raw_part_inner)
+    }
+    pub fn preamble_and_body(&self) -> &'a [u8] {
+        pointers::with_preamble(self.raw_part_outer, self.raw_part_inner)
+    }
+    pub fn body_and_epilogue(&self) -> &'a [u8] {
+        pointers::with_epilogue(self.raw_part_outer, self.raw_part_inner)
     }
 }
 
@@ -27,19 +53,25 @@ pub fn multipart<'a>(
     let m = m.clone();
 
     move |input| {
-        let bound = m.interpreted.boundary.as_bytes();
-        let (mut input_loop, preamble) = part::part_raw(bound)(input)?;
+        // init
+        let outer_orig = input;
+        let bound = m.interpreted_type.boundary.as_bytes();
         let mut mparts: Vec<AnyPart> = vec![];
+
+        // skip preamble
+        let (mut input_loop, _) = part::part_raw(bound)(input)?;
+        let inner_orig = input_loop;
+
         loop {
             let input = match boundary(bound)(input_loop) {
                 Err(_) => {
                     return Ok((
                         input_loop,
                         Multipart {
-                            interpreted: m.clone(),
+                            mime: m.clone(),
                             children: mparts,
-                            preamble,
-                            epilogue: &[],
+                            raw_part_inner: pointers::parsed(inner_orig, input_loop),
+                            raw_part_outer: pointers::parsed(outer_orig, input_loop),
                         },
                     ))
                 }
@@ -47,10 +79,13 @@ pub fn multipart<'a>(
                     return Ok((
                         inp,
                         Multipart {
-                            interpreted: m.clone(),
+                            mime: m.clone(),
                             children: mparts,
-                            preamble,
-                            epilogue: &[],
+                            raw_part_inner: pointers::parsed(inner_orig, inp),
+                            raw_part_outer: pointers::parsed(
+                                outer_orig,
+                                &outer_orig[outer_orig.len()..],
+                            ),
                         },
                     ))
                 }
@@ -58,23 +93,40 @@ pub fn multipart<'a>(
             };
 
             // parse mime headers, otherwise pick default mime
-            let (input, naive_mime) = match header(mime::field::content)(input) {
-                Ok((input, (known, unknown, bad))) => (input, known.into_iter().collect::<mime::NaiveMIME>().with_opt(unknown).with_bad(bad)),
+            let (input, naive_mime) = match header::header_kv(input) {
+                Ok((input_eom, fields)) => {
+                    let raw_hdrs = pointers::parsed(input, input_eom);
+                    let mime = fields
+                        .iter()
+                        .flat_map(mime::field::Content::try_from)
+                        .into_iter()
+                        .collect::<mime::NaiveMIME>();
+
+                    let mime = mime.with_kv(fields).with_raw(raw_hdrs);
+
+                    (input_eom, mime)
+                }
                 Err(_) => (input, mime::NaiveMIME::default()),
             };
 
             // interpret mime according to context
-            let mime = match m.interpreted.subtype {
-                mime::r#type::MultipartSubtype::Digest => naive_mime.to_interpreted::<mime::WithDigestDefault>().into(),
-                _ => naive_mime.to_interpreted::<mime::WithGenericDefault>().into(),
+            let mime = match m.interpreted_type.subtype {
+                mime::r#type::MultipartSubtype::Digest => naive_mime
+                    .to_interpreted::<mime::WithDigestDefault>()
+                    .into(),
+                _ => naive_mime
+                    .to_interpreted::<mime::WithGenericDefault>()
+                    .into(),
             };
 
             // parse raw part
             let (input, rpart) = part::part_raw(bound)(input)?;
 
             // parse mime body
-            mparts.push(part::to_anypart(mime, rpart));
-
+            // -- we do not keep the input as we are using the
+            // part_raw function as our cursor here.
+            let (_, part) = part::anypart(mime)(rpart)?;
+            mparts.push(part);
 
             input_loop = input;
         }
@@ -83,47 +135,72 @@ pub fn multipart<'a>(
 
 //--- Message
 
-#[derive(Debug, PartialEq)]
+#[derive(PartialEq)]
 pub struct Message<'a> {
-    pub interpreted: mime::MIME<'a, mime::r#type::Message>,
+    pub mime: mime::MIME<'a, mime::r#type::DeductibleMessage>,
     pub imf: imf::Imf<'a>,
     pub child: Box<AnyPart<'a>>,
-    pub epilogue: &'a [u8],
+
+    pub raw_part: &'a [u8],
+    pub raw_headers: &'a [u8],
+    pub raw_body: &'a [u8],
 }
-impl<'a> Message<'a> {
-    pub fn with_epilogue(mut self, e: &'a [u8]) -> Self {
-        self.epilogue = e;
-        self
+impl<'a> fmt::Debug for Message<'a> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.debug_struct("part::Message")
+            .field("mime", &self.mime)
+            .field("imf", &self.imf)
+            .field("child", &self.child)
+            .field("raw_part", &String::from_utf8_lossy(self.raw_part))
+            .field("raw_headers", &String::from_utf8_lossy(self.raw_headers))
+            .field("raw_body", &String::from_utf8_lossy(self.raw_body))
+            .finish()
     }
-} 
+}
 
 pub fn message<'a>(
-    m: mime::MIME<'a, mime::r#type::Message>,
+    m: mime::MIME<'a, mime::r#type::DeductibleMessage>,
 ) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], Message<'a>> {
     move |input: &[u8]| {
+        let orig = input;
+
         // parse header fields
-        let (input, (known, unknown, bad)): (_, (Vec::<MixedField>, Vec<header::Kv>, Vec<&[u8]>)) =
-            header(part::field::mixed_field)(input)?;
+        let (input, headers) = header::header_kv(input)?;
 
+        // extract raw parts 1/2
+        let raw_headers = pointers::parsed(orig, input);
+        let body_orig = input;
+
+        //---------------
         // aggregate header fields
-        let (naive_mime, imf) = part::field::sections(known);
+        let (naive_mime, imf) = part::field::split_and_build(&headers);
 
-        // attach bad headers to imf
-        let imf = imf.with_opt(unknown).with_bad(bad);
+        // Bind headers to mime
+        let naive_mime = naive_mime.with_kv(headers);
 
-        // interpret headers to choose a mime type
-        let in_mime = naive_mime.to_interpreted::<mime::WithGenericDefault>().into();
+        // interpret headers to choose the child mime type
+        let in_mime = naive_mime
+            .with_raw(raw_headers)
+            .to_interpreted::<mime::WithGenericDefault>()
+            .into();
+        //---------------
 
-        // parse this mimetype
-        let part = part::to_anypart(in_mime, input);
+        // parse a part following this mime specification
+        let (input, part) = part::anypart(in_mime)(input)?;
+
+        // extract raw parts 2/2
+        let raw_body = pointers::parsed(body_orig, input);
+        let raw_part = pointers::parsed(orig, input);
 
         Ok((
-            &[],
+            input,
             Message {
-                interpreted: m.clone(),
+                mime: m.clone(),
                 imf,
+                raw_part,
+                raw_headers,
+                raw_body,
                 child: Box::new(part),
-                epilogue: &[],
             },
         ))
     }
@@ -135,22 +212,21 @@ mod tests {
     use crate::part::discrete::Text;
     use crate::part::AnyPart;
     use crate::text::encoding::{Base64Word, EncodedWord, QuotedChunk, QuotedWord};
-    use crate::text::misc_token::{Phrase, UnstrToken, Unstructured, Word, MIMEWord};
+    use crate::text::misc_token::{MIMEWord, Phrase, UnstrToken, Unstructured, Word};
     use crate::text::quoted::QuotedString;
     use chrono::{FixedOffset, TimeZone};
 
     #[test]
     fn test_multipart() {
         let base_mime = mime::MIME {
-            interpreted: mime::r#type::Multipart {
+            interpreted_type: mime::r#type::Multipart {
                 subtype: mime::r#type::MultipartSubtype::Alternative,
                 boundary: "simple boundary".to_string(),
             },
-            parsed: mime::NaiveMIME::default(),
+            fields: mime::NaiveMIME::default(),
         };
 
-        assert_eq!(
-            multipart(base_mime.clone())(b"This is the preamble.  It is to be ignored, though it
+        let input = b"This is the preamble.  It is to be ignored, though it
 is a handy place for composition agents to include an
 explanatory note to non-MIME conformant readers.
 
@@ -167,30 +243,50 @@ It DOES end with a linebreak.
 --simple boundary--
 
 This is the epilogue. It is also to be ignored.
-"),
+";
+
+        let inner = b"
+--simple boundary
+
+This is implicitly typed plain US-ASCII text.
+It does NOT end with a linebreak.
+--simple boundary
+Content-type: text/plain; charset=us-ascii
+
+This is explicitly typed plain US-ASCII text.
+It DOES end with a linebreak.
+
+--simple boundary--
+";
+
+        assert_eq!(
+            multipart(base_mime.clone())(input),
             Ok((&b"\nThis is the epilogue. It is also to be ignored.\n"[..],
                 Multipart {
-                    interpreted: base_mime,
-                    preamble: &b"This is the preamble.  It is to be ignored, though it\nis a handy place for composition agents to include an\nexplanatory note to non-MIME conformant readers.\n"[..],
-                    epilogue: &b""[..],
+                    mime: base_mime,
+                    raw_part_outer: input,
+                    raw_part_inner: inner,
                     children: vec![
                         AnyPart::Txt(Text {
-                            interpreted: mime::MIME {
-                                interpreted: mime::r#type::Text {
+                            mime: mime::MIME {
+                                interpreted_type: mime::r#type::Deductible::Inferred(mime::r#type::Text {
                                     subtype: mime::r#type::TextSubtype::Plain,
-                                    charset: mime::charset::EmailCharset::US_ASCII,
+                                    charset: mime::r#type::Deductible::Inferred(mime::charset::EmailCharset::US_ASCII),
+                                }),
+                                fields: mime::NaiveMIME {
+                                    raw: &b"\n"[..],
+                                    ..mime::NaiveMIME::default()
                                 },
-                                parsed: mime::NaiveMIME::default(),
                             },
                             body: &b"This is implicitly typed plain US-ASCII text.\nIt does NOT end with a linebreak."[..],
                         }),
                         AnyPart::Txt(Text {
-                            interpreted: mime::MIME { 
-                                interpreted: mime::r#type::Text {
+                            mime: mime::MIME {
+                                interpreted_type: mime::r#type::Deductible::Explicit(mime::r#type::Text {
                                     subtype: mime::r#type::TextSubtype::Plain,
-                                    charset: mime::charset::EmailCharset::US_ASCII,
-                                },
-                                parsed: mime::NaiveMIME {
+                                    charset: mime::r#type::Deductible::Explicit(mime::charset::EmailCharset::US_ASCII),
+                                }),
+                                fields: mime::NaiveMIME {
                                     ctype: Some(mime::r#type::NaiveType {
                                         main: &b"text"[..],
                                         sub: &b"plain"[..],
@@ -201,6 +297,10 @@ This is the epilogue. It is also to be ignored.
                                             }
                                         ]
                                     }),
+                                    raw: &b"Content-type: text/plain; charset=us-ascii\n\n"[..],
+                                    kv: vec![
+                                        header::Field::Good(header::Kv2(&b"Content-type"[..], &b"text/plain; charset=us-ascii"[..]))
+                                    ],
                                     ..mime::NaiveMIME::default()
                                 },
                             },
@@ -259,14 +359,90 @@ OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
 "#
         .as_bytes();
 
-        let base_mime = mime::MIME::<mime::r#type::Message>::default();
+        let hdrs = br#"Date: Sat, 8 Jul 2023 07:14:29 +0200
+From: Grrrnd Zero <grrrndzero@example.org>
+To: John Doe <jdoe@machine.example>
+CC: =?ISO-8859-1?Q?Andr=E9?= Pirard <PIRARD@vm1.ulg.ac.be>
+Subject: =?ISO-8859-1?B?SWYgeW91IGNhbiByZWFkIHRoaXMgeW8=?=
+    =?ISO-8859-2?B?dSB1bmRlcnN0YW5kIHRoZSBleGFtcGxlLg==?=
+X-Unknown: something something
+Bad entry
+  on multiple lines
+Message-ID: <NTAxNzA2AC47634Y366BAMTY4ODc5MzQyODY0ODY5@www.grrrndzero.org>
+MIME-Version: 1.0
+Content-Type: multipart/alternative;
+ boundary="b1_e376dc71bafc953c0b0fdeb9983a9956"
+Content-Transfer-Encoding: 7bit
+
+"#;
+
+        let body = br#"This is a multi-part message in MIME format.
+
+--b1_e376dc71bafc953c0b0fdeb9983a9956
+Content-Type: text/plain; charset=utf-8
+Content-Transfer-Encoding: quoted-printable
+
+GZ
+OoOoO
+oOoOoOoOo
+oOoOoOoOoOoOoOoOo
+oOoOoOoOoOoOoOoOoOoOoOo
+oOoOoOoOoOoOoOoOoOoOoOoOoOoOo
+OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO
+
+--b1_e376dc71bafc953c0b0fdeb9983a9956
+Content-Type: text/html; charset=us-ascii
+
+<div style="text-align: center;"><strong>GZ</strong><br />
+OoOoO<br />
+oOoOoOoOo<br />
+oOoOoOoOoOoOoOoOo<br />
+oOoOoOoOoOoOoOoOoOoOoOo<br />
+oOoOoOoOoOoOoOoOoOoOoOoOoOoOo<br />
+OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
+</div>
+
+--b1_e376dc71bafc953c0b0fdeb9983a9956--
+"#;
+
+        let inner = br#"
+--b1_e376dc71bafc953c0b0fdeb9983a9956
+Content-Type: text/plain; charset=utf-8
+Content-Transfer-Encoding: quoted-printable
+
+GZ
+OoOoO
+oOoOoOoOo
+oOoOoOoOoOoOoOoOo
+oOoOoOoOoOoOoOoOoOoOoOo
+oOoOoOoOoOoOoOoOoOoOoOoOoOoOo
+OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO
+
+--b1_e376dc71bafc953c0b0fdeb9983a9956
+Content-Type: text/html; charset=us-ascii
+
+<div style="text-align: center;"><strong>GZ</strong><br />
+OoOoO<br />
+oOoOoOoOo<br />
+oOoOoOoOoOoOoOoOo<br />
+oOoOoOoOoOoOoOoOoOoOoOo<br />
+oOoOoOoOoOoOoOoOoOoOoOoOoOoOo<br />
+OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
+</div>
+
+--b1_e376dc71bafc953c0b0fdeb9983a9956--
+"#;
+
+        let base_mime = mime::MIME::<mime::r#type::DeductibleMessage>::default();
         assert_eq!(
             message(base_mime.clone())(fullmail),
             Ok((
                 &[][..],
                 Message {
-                    interpreted: base_mime,
-                    epilogue: &b""[..],
+                    mime: base_mime,
+                    raw_part: fullmail,
+                    raw_headers: hdrs,
+                    raw_body: body,
                     imf: imf::Imf {
                         date: Some(FixedOffset::east_opt(2 * 3600)
                             .unwrap()
@@ -330,24 +506,15 @@ OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
                             right: &b"www.grrrndzero.org"[..],
                         }),
                         mime_version: Some(imf::mime::Version { major: 1, minor: 0}),
-                        header_ext: vec![
-                            header::Kv(&b"X-Unknown"[..], Unstructured(vec![
-                                UnstrToken::Plain(&b"something"[..]),
-                                UnstrToken::Plain(&b"something"[..]),
-                            ]))
-                        ],
-                        header_bad: vec![
-                            &b"Bad entry\n  on multiple lines\n"[..],
-                        ],
                         ..imf::Imf::default()
                     },
                     child: Box::new(AnyPart::Mult(Multipart {
-                        interpreted: mime::MIME {
-                            interpreted: mime::r#type::Multipart {
+                        mime: mime::MIME {
+                            interpreted_type: mime::r#type::Multipart {
                                 subtype: mime::r#type::MultipartSubtype::Alternative,
                                 boundary: "b1_e376dc71bafc953c0b0fdeb9983a9956".to_string(),
                             },
-                            parsed: mime::NaiveMIME {
+                            fields: mime::NaiveMIME {
                                 ctype: Some(mime::r#type::NaiveType {
                                     main: &b"multipart"[..],
                                     sub: &b"alternative"[..],
@@ -358,19 +525,33 @@ OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
                                         }
                                     ]
                                 }),
+                                raw: hdrs,
+                                kv: vec![
+                                    header::Field::Good(header::Kv2(&b"Date"[..], &b"Sat, 8 Jul 2023 07:14:29 +0200"[..])),
+                                    header::Field::Good(header::Kv2(&b"From"[..], &b"Grrrnd Zero <grrrndzero@example.org>"[..])),
+                                    header::Field::Good(header::Kv2(&b"To"[..], &b"John Doe <jdoe@machine.example>"[..])),
+                                    header::Field::Good(header::Kv2(&b"CC"[..], &b"=?ISO-8859-1?Q?Andr=E9?= Pirard <PIRARD@vm1.ulg.ac.be>"[..])),
+                                    header::Field::Good(header::Kv2(&b"Subject"[..], &b"=?ISO-8859-1?B?SWYgeW91IGNhbiByZWFkIHRoaXMgeW8=?=\n    =?ISO-8859-2?B?dSB1bmRlcnN0YW5kIHRoZSBleGFtcGxlLg==?="[..])),
+                                    header::Field::Good(header::Kv2(&b"X-Unknown"[..], &b"something something"[..])),
+                                    header::Field::Bad(&b"Bad entry\n  on multiple lines\n"[..]),
+                                    header::Field::Good(header::Kv2(&b"Message-ID"[..], &b"<NTAxNzA2AC47634Y366BAMTY4ODc5MzQyODY0ODY5@www.grrrndzero.org>"[..])),
+                                    header::Field::Good(header::Kv2(&b"MIME-Version"[..], &b"1.0"[..])),
+                                    header::Field::Good(header::Kv2(&b"Content-Type"[..], &b"multipart/alternative;\n boundary=\"b1_e376dc71bafc953c0b0fdeb9983a9956\""[..])),
+                                    header::Field::Good(header::Kv2(&b"Content-Transfer-Encoding"[..], &b"7bit"[..])),
+                                ],
                                 ..mime::NaiveMIME::default()
                             },
                         },
-                        preamble: &b"This is a multi-part message in MIME format.\n"[..],
-                        epilogue: &b""[..],
+                        raw_part_inner: inner,
+                        raw_part_outer: body,
                         children: vec![
                             AnyPart::Txt(Text {
-                                interpreted: mime::MIME {
-                                    interpreted: mime::r#type::Text {
+                                mime: mime::MIME {
+                                    interpreted_type: mime::r#type::Deductible::Explicit(mime::r#type::Text {
                                         subtype: mime::r#type::TextSubtype::Plain,
-                                        charset: mime::charset::EmailCharset::UTF_8,
-                                    },
-                                    parsed: mime::NaiveMIME {
+                                        charset: mime::r#type::Deductible::Explicit(mime::charset::EmailCharset::UTF_8),
+                                    }),
+                                    fields: mime::NaiveMIME {
                                         ctype: Some(mime::r#type::NaiveType {
                                             main: &b"text"[..],
                                             sub: &b"plain"[..],
@@ -382,19 +563,24 @@ OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
                                             ]
                                         }),
                                         transfer_encoding: mime::mechanism::Mechanism::QuotedPrintable,
+                                        kv: vec![
+                                            header::Field::Good(header::Kv2(&b"Content-Type"[..], &b"text/plain; charset=utf-8"[..])),
+                                            header::Field::Good(header::Kv2(&b"Content-Transfer-Encoding"[..], &b"quoted-printable"[..])),
+                                        ],
+                                        raw: &b"Content-Type: text/plain; charset=utf-8\nContent-Transfer-Encoding: quoted-printable\n\n"[..],
                                         ..mime::NaiveMIME::default()
                                     }
                                 },
                                 body: &b"GZ\nOoOoO\noOoOoOoOo\noOoOoOoOoOoOoOoOo\noOoOoOoOoOoOoOoOoOoOoOo\noOoOoOoOoOoOoOoOoOoOoOoOoOoOo\nOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO\n"[..],
                             }),
                             AnyPart::Txt(Text {
-                                interpreted: mime::MIME {
-                                    interpreted: mime::r#type::Text {
+                                mime: mime::MIME {
+                                    interpreted_type: mime::r#type::Deductible::Explicit(mime::r#type::Text {
                                         subtype: mime::r#type::TextSubtype::Html,
-                                        charset: mime::charset::EmailCharset::US_ASCII,
-                                    },
+                                        charset: mime::r#type::Deductible::Explicit(mime::charset::EmailCharset::US_ASCII),
+                                    }),
 
-                                    parsed: mime::NaiveMIME {
+                                    fields: mime::NaiveMIME {
                                         ctype: Some(mime::r#type::NaiveType {
                                             main: &b"text"[..],
                                             sub: &b"html"[..],
@@ -404,7 +590,11 @@ OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO<br />
                                                     value: MIMEWord::Atom(&b"us-ascii"[..]),
                                                 }
                                             ]
-                                        }),                             
+                                        }),
+                                        kv: vec![
+                                            header::Field::Good(header::Kv2(&b"Content-Type"[..], &b"text/html; charset=us-ascii"[..])),
+                                        ],
+                                        raw: &b"Content-Type: text/html; charset=us-ascii\n\n"[..],
                                         ..mime::NaiveMIME::default()
                                     },
                                 },

src/part/discrete.rs

@@ -4,36 +4,30 @@ use crate::mime;
 
 #[derive(PartialEq)]
 pub struct Text<'a> {
-    pub interpreted: mime::MIME<'a, mime::r#type::Text>,
+    pub mime: mime::MIME<'a, mime::r#type::DeductibleText>,
     pub body: &'a [u8],
 }
 
 impl<'a> fmt::Debug for Text<'a> {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt.debug_struct("part::Text")
-            .field("mime", &self.interpreted)
-            .field(
-                "body",
-                &format_args!("\"{}\"", String::from_utf8_lossy(self.body)),
-            )
+            .field("mime", &self.mime)
+            .field("body", &String::from_utf8_lossy(self.body))
             .finish()
     }
 }
 
 #[derive(PartialEq)]
 pub struct Binary<'a> {
-    pub interpreted: mime::MIME<'a, mime::r#type::Binary>,
+    pub mime: mime::MIME<'a, mime::r#type::Binary>,
     pub body: &'a [u8],
 }
 
 impl<'a> fmt::Debug for Binary<'a> {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt.debug_struct("part::Binary")
-            .field("mime", &self.interpreted)
-            .field(
-                "body",
-                &format_args!("\"{}\"", String::from_utf8_lossy(self.body)),
-            )
+            .field("mime", &self.mime)
+            .field("body", &String::from_utf8_lossy(self.body))
             .finish()
     }
 }

src/part/field.rs

@@ -1,50 +1,24 @@
-use nom::{branch::alt, combinator::map, IResult};
-
+use crate::header;
 use crate::imf;
 use crate::mime;
 
-pub enum MixedField<'a> {
-    MIME(mime::field::Content<'a>),
-    IMF(imf::field::Field<'a>),
-}
-#[allow(dead_code)]
-impl<'a> MixedField<'a> {
-    pub fn mime(&self) -> Option<&mime::field::Content<'a>> {
-        match self {
-            Self::MIME(v) => Some(v),
-            _ => None,
-        }
-    }
-    pub fn to_mime(self) -> Option<mime::field::Content<'a>> {
-        match self {
-            Self::MIME(v) => Some(v),
-            _ => None,
-        }
-    }
-    pub fn imf(&self) -> Option<&imf::field::Field<'a>> {
-        match self {
-            Self::IMF(v) => Some(v),
-            _ => None,
-        }
-    }
-    pub fn to_imf(self) -> Option<imf::field::Field<'a>> {
-        match self {
-            Self::IMF(v) => Some(v),
-            _ => None,
-        }
-    }
-}
+pub fn split_and_build<'a>(v: &Vec<header::Field<'a>>) -> (mime::NaiveMIME<'a>, imf::Imf<'a>) {
+    let (mimev, imfv) = v.iter().fold(
+        (
+            Vec::<mime::field::Content>::new(),
+            Vec::<imf::field::Field>::new(),
+        ),
+        |(mut mime, mut imf), f| {
+            if let Ok(m) = mime::field::Content::try_from(f) {
+                mime.push(m);
+            } else if let Ok(i) = imf::field::Field::try_from(f) {
+                imf.push(i);
+            }
+            (mime, imf)
+        },
+    );
 
-pub fn sections<'a>(list: Vec<MixedField<'a>>) -> (mime::NaiveMIME<'a>, imf::Imf<'a>) {
-    let (v1, v2): (Vec<MixedField>, Vec<_>) = list.into_iter().partition(|v| v.mime().is_some());
-    let mime = v1.into_iter().flat_map(MixedField::to_mime).collect::<mime::NaiveMIME>();
-    let imf = v2.into_iter().flat_map(MixedField::to_imf).collect::<imf::Imf>();
-    (mime, imf)
-}
-
-pub fn mixed_field(input: &[u8]) -> IResult<&[u8], MixedField> {
-    alt((
-        map(mime::field::content, MixedField::MIME),
-        map(imf::field::field, MixedField::IMF),
-    ))(input)
+    let fmime = mimev.into_iter().collect::<mime::NaiveMIME>();
+    let fimf = imfv.into_iter().collect::<imf::Imf>();
+    (fmime, fimf)
 }

src/part/mod.rs

@@ -17,7 +17,7 @@ use nom::{
 };
 
 use crate::mime;
-use crate::mime::AnyMIME;
+use crate::mime::{AnyMIME, NaiveMIME};
 use crate::part::{
     composite::{message, multipart, Message, Multipart},
     discrete::{Binary, Text},
@@ -58,30 +58,61 @@ impl<'a> AnyPart<'a> {
             _ => None,
         }
     }
+    pub fn mime(&self) -> &NaiveMIME<'a> {
+        match self {
+            Self::Mult(v) => &v.mime.fields,
+            Self::Msg(v) => &v.mime.fields,
+            Self::Txt(v) => &v.mime.fields,
+            Self::Bin(v) => &v.mime.fields,
+        }
+    }
+}
+impl<'a> From<Multipart<'a>> for AnyPart<'a> {
+    fn from(m: Multipart<'a>) -> Self {
+        Self::Mult(m)
+    }
+}
+impl<'a> From<Message<'a>> for AnyPart<'a> {
+    fn from(m: Message<'a>) -> Self {
+        Self::Msg(m)
+    }
 }
 
-pub fn to_anypart<'a>(m: AnyMIME<'a>, rpart: &'a [u8]) -> AnyPart<'a> {
-    match m {
-        AnyMIME::Mult(a) => multipart(a)(rpart)
-            .map(|(rest, multi)| AnyPart::Mult(multi.with_epilogue(rest)))
-            .unwrap_or(AnyPart::Txt(Text {
-                interpreted: mime::MIME::<mime::r#type::Text>::default(),
-                body: rpart,
-            })),
-        AnyMIME::Msg(a) => message(a)(rpart)
-            .map(|(rest, msg)| AnyPart::Msg(msg.with_epilogue(rest)))
-            .unwrap_or(AnyPart::Txt(Text {
-                interpreted: mime::MIME::<mime::r#type::Text>::default(),
-                body: rpart,
-            })),
-        AnyMIME::Txt(a) => AnyPart::Txt(Text {
-            interpreted: a,
-            body: rpart,
-        }),
-        AnyMIME::Bin(a) => AnyPart::Bin(Binary {
-            interpreted: a,
-            body: rpart,
-        }),
+/// Parse any type of part
+///
+/// ## Note
+///
+/// Multiparts are a bit special as they have a clearly delimited beginning
+/// and end contrary to all the other parts that are going up to the end of the buffer
+pub fn anypart<'a>(m: AnyMIME<'a>) -> impl FnOnce(&'a [u8]) -> IResult<&'a [u8], AnyPart<'a>> {
+    move |input| {
+        let part = match m {
+            AnyMIME::Mult(a) => multipart(a)(input)
+                .map(|(_, multi)| multi.into())
+                .unwrap_or(AnyPart::Txt(Text {
+                    mime: mime::MIME::<mime::r#type::DeductibleText>::default(),
+                    body: input,
+                })),
+            AnyMIME::Msg(a) => {
+                message(a)(input)
+                    .map(|(_, msg)| msg.into())
+                    .unwrap_or(AnyPart::Txt(Text {
+                        mime: mime::MIME::<mime::r#type::DeductibleText>::default(),
+                        body: input,
+                    }))
+            }
+            AnyMIME::Txt(a) => AnyPart::Txt(Text {
+                mime: a,
+                body: input,
+            }),
+            AnyMIME::Bin(a) => AnyPart::Bin(Binary {
+                mime: a,
+                body: input,
+            }),
+        };
+
+        // This function always consumes the whole input
+        Ok((&input[input.len()..], part))
     }
 }
 

src/pointers.rs

@@ -0,0 +1,55 @@
+pub fn parsed<'a>(input: &'a [u8], rest: &'a [u8]) -> &'a [u8] {
+    let start = input.as_ptr();
+    let offset = rest.as_ptr();
+    let idx = (offset as usize - start as usize) / std::mem::size_of::<u8>();
+    assert!(idx <= input.len());
+    &input[..idx]
+}
+
+pub fn rest<'a>(input: &'a [u8], parsed: &'a [u8]) -> &'a [u8] {
+    let start = input.as_ptr();
+    let offset = (&parsed[parsed.len()..]).as_ptr();
+    let idx = (offset as usize - start as usize) / std::mem::size_of::<u8>();
+    assert!(idx <= input.len());
+    &input[idx..]
+}
+
+pub fn with_preamble<'a>(input: &'a [u8], parsed: &'a [u8]) -> &'a [u8] {
+    let start = input.as_ptr();
+    let offset = (&parsed[parsed.len()..]).as_ptr();
+    let idx = (offset as usize - start as usize) / std::mem::size_of::<u8>();
+    assert!(idx <= input.len());
+    &input[..idx]
+}
+
+pub fn with_epilogue<'a>(input: &'a [u8], rest: &'a [u8]) -> &'a [u8] {
+    let start = input.as_ptr();
+    let offset = rest.as_ptr();
+    let idx = (offset as usize - start as usize) / std::mem::size_of::<u8>();
+    assert!(idx <= input.len());
+    &input[idx..]
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_all() {
+        let outer = b"aa bb cc";
+        let inner = &outer[3..5];
+        assert_eq!(inner, b"bb");
+
+        let p = parsed(outer, inner);
+        assert_eq!(p, b"aa ");
+
+        let r = rest(outer, inner);
+        assert_eq!(r, b" cc");
+
+        let wp = with_preamble(outer, inner);
+        assert_eq!(wp, b"aa bb");
+
+        let we = with_epilogue(outer, inner);
+        assert_eq!(we, b"bb cc");
+    }
+}

src/text/ascii.rs

@@ -136,6 +136,11 @@ pub const TILDE: u8 = 0x7E; // ~
 // GROUP OF CHARACTERS
 // -- CRLF
 pub const CRLF: &[u8] = &[CR, LF];
+// -- CRCRLF
+// Sometimes portable libraries replace transparently
+// the "\n" with "\r\n" on Windows. When developpers
+// explicitly write "\r\n", the library generates "\r\r\n".
+pub const CRCRLF: &[u8] = &[CR, CR, LF];
 
 // -- WHITESPACE
 pub const WS: &[u8] = &[HT, SP];

src/text/whitespace.rs

@@ -22,7 +22,12 @@ use nom::{
 /// \r or \n is allowed nowhere else, so we also add this support.
 
 pub fn obs_crlf(input: &[u8]) -> IResult<&[u8], &[u8]> {
-    alt((tag(ascii::CRLF), tag(&[ascii::CR]), tag(&[ascii::LF])))(input)
+    alt((
+        tag(ascii::CRLF),
+        tag(ascii::CRCRLF),
+        tag(&[ascii::CR]),
+        tag(&[ascii::LF]),
+    ))(input)
 }
 
 /// ```abnf