From 3403368e71ec846091e55f713af5ba49481d92a3 Mon Sep 17 00:00:00 2001
From: Mauro D <mauro@stalw.art>
Date: Sat, 24 Dec 2022 16:57:50 +0000
Subject: [PATCH] LineReceiver implementation.

---
 src/lib.rs               |  1 +
 src/request/receiver.rs  | 32 +++++++++++++++++++++++++++++++-
 src/response/generate.rs |  1 +
 src/response/mod.rs      |  2 ++
 src/response/parser.rs   |  3 +++
 5 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/src/lib.rs b/src/lib.rs
index a55eb58..62b8e05 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -192,6 +192,7 @@ pub const EXT_SMTP_UTF8: u32 = 1 << 23;
 pub const EXT_START_TLS: u32 = 1 << 24;
 pub const EXT_VERB: u32 = 1 << 25;
 pub const EXT_EXPN: u32 = 1 << 26;
+pub const EXT_VRFY: u32 = 1 << 27;
 
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum MtPriority {
diff --git a/src/request/receiver.rs b/src/request/receiver.rs
index 1722f0d..7d0234d 100644
--- a/src/request/receiver.rs
+++ b/src/request/receiver.rs
@@ -2,7 +2,7 @@ use std::slice::Iter;
 
 use crate::{Error, Request};
 
-const MAX_LINE_LENGTH: usize = 2048;
+pub const MAX_LINE_LENGTH: usize = 2048;
 
 #[derive(Default)]
 pub struct RequestReceiver {
@@ -31,6 +31,12 @@ pub struct DummyDataReceiver {
 #[derive(Default)]
 pub struct DummyLineReceiver {}
 
+#[derive(Default)]
+pub struct LineReceiver<T> {
+    pub buf: Vec<u8>,
+    pub state: T,
+}
+
 impl RequestReceiver {
     pub fn ingest(
         &mut self,
@@ -180,6 +186,30 @@ impl DummyDataReceiver {
     }
 }
 
+impl<T> LineReceiver<T> {
+    pub fn new(state: T) -> Self {
+        Self {
+            buf: Vec::with_capacity(32),
+            state,
+        }
+    }
+
+    pub fn ingest(&mut self, bytes: &mut Iter<'_, u8>) -> bool {
+        for &ch in bytes {
+            match ch {
+                b'\n' => return true,
+                b'\r' => (),
+                _ => {
+                    if self.buf.len() < MAX_LINE_LENGTH {
+                        self.buf.push(ch);
+                    }
+                }
+            }
+        }
+        false
+    }
+}
+
 impl DummyLineReceiver {
     pub fn ingest(&mut self, bytes: &mut Iter<'_, u8>) -> bool {
         for &ch in bytes {
diff --git a/src/response/generate.rs b/src/response/generate.rs
index 48de3de..97daa0d 100644
--- a/src/response/generate.rs
+++ b/src/response/generate.rs
@@ -60,6 +60,7 @@ impl<T: Display> EhloResponse<T> {
                 EXT_ENHANCED_STATUS_CODES => write!(writer, "ENHANCEDSTATUSCODES\r\n"),
                 EXT_ETRN => write!(writer, "ETRN\r\n"),
                 EXT_EXPN => write!(writer, "EXPN\r\n"),
+                EXT_VRFY => write!(writer, "VRFY\r\n"),
                 EXT_FUTURE_RELEASE => write!(
                     writer,
                     "FUTURERELEASE {} {}\r\n",
diff --git a/src/response/mod.rs b/src/response/mod.rs
index 4fdb351..b07ad15 100644
--- a/src/response/mod.rs
+++ b/src/response/mod.rs
@@ -90,6 +90,8 @@ pub(crate) const ETRN: u128 =
     (b'E' as u128) | (b'T' as u128) << 8 | (b'R' as u128) << 16 | (b'N' as u128) << 24;
 pub(crate) const EXPN: u128 =
     (b'E' as u128) | (b'X' as u128) << 8 | (b'P' as u128) << 16 | (b'N' as u128) << 24;
+pub(crate) const VRFY: u128 =
+    (b'V' as u128) | (b'R' as u128) << 8 | (b'F' as u128) << 16 | (b'Y' as u128) << 24;
 pub(crate) const FUTURERELEASE: u128 = (b'F' as u128)
     | (b'U' as u128) << 8
     | (b'T' as u128) << 16
diff --git a/src/response/parser.rs b/src/response/parser.rs
index d04a4b6..4168747 100644
--- a/src/response/parser.rs
+++ b/src/response/parser.rs
@@ -201,6 +201,7 @@ impl EhloResponse<String> {
                     }
                     ETRN => EXT_ETRN,
                     EXPN => EXT_EXPN,
+                    VRFY => EXT_VRFY,
                     FUTURERELEASE => {
                         let max_interval = if parser.stop_char != LF {
                             parser.size()?
@@ -327,6 +328,7 @@ mod tests {
                     "250-ENHANCEDSTATUSCODES\n",
                     "250-ETRN\n",
                     "250-EXPN\n",
+                    "250-VRFY\n",
                     "250-FUTURERELEASE 1234 5678\n",
                     "250-HELP\n",
                     "250-MT-PRIORITY\n",
@@ -355,6 +357,7 @@ mod tests {
                         | EXT_ENHANCED_STATUS_CODES
                         | EXT_ETRN
                         | EXT_EXPN
+                        | EXT_VRFY
                         | EXT_FUTURE_RELEASE
                         | EXT_HELP
                         | EXT_MT_PRIORITY