Merging upstream version 1.70.0+dfsg2.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 174 insertions, 0 deletions

diff --git a/vendor/vte_generate_state_changes/src/lib.rs b/vendor/vte_generate_state_changes/src/lib.rs
new file mode 100644
index 000000000..5cfb3acf2
--- /dev/null
+++ b/vendor/vte_generate_state_changes/src/lib.rs
@@ -0,0 +1,174 @@
+extern crate proc_macro;
+
+use std::iter::Peekable;
+
+use proc_macro2::TokenTree::{Group, Literal, Punct};
+use proc_macro2::{token_stream, TokenStream, TokenTree};
+use quote::quote;
+
+/// Create a `const fn` which will return an array with all state changes.
+#[proc_macro]
+pub fn generate_state_changes(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    // Convert from proc_macro -> proc_macro2
+    let item: TokenStream = item.into();
+    let mut iter = item.into_iter().peekable();
+
+    // Determine output function name
+    let fn_name = iter.next().unwrap();
+
+    // Separator between name and body with state changes
+    expect_punct(&mut iter, ',');
+
+    // Create token stream to assign each state change to the array
+    let assignments_stream = states_stream(&mut iter);
+
+    quote!(
+        const fn #fn_name() -> [[u8; 256]; 16] {
+            let mut state_changes = [[0; 256]; 16];
+
+            #assignments_stream
+
+            state_changes
+        }
+    )
+    .into()
+}
+
+/// Generate the array assignment statements for all origin states.
+fn states_stream(iter: &mut impl Iterator<Item = TokenTree>) -> TokenStream {
+    let mut states_stream = next_group(iter).into_iter().peekable();
+
+    // Loop over all origin state entries
+    let mut tokens = quote!();
+    while states_stream.peek().is_some() {
+        // Add all mappings for this state
+        tokens.extend(state_entry_stream(&mut states_stream));
+
+        // Allow trailing comma
+        optional_punct(&mut states_stream, ',');
+    }
+    tokens
+}
+
+/// Generate the array assignment statements for one origin state.
+fn state_entry_stream(iter: &mut Peekable<token_stream::IntoIter>) -> TokenStream {
+    // Origin state name
+    let state = iter.next().unwrap().into();
+
+    // Token stream with all the byte->target mappings
+    let mut changes_stream = next_group(iter).into_iter().peekable();
+
+    let mut tokens = quote!();
+    while changes_stream.peek().is_some() {
+        // Add next mapping for this state
+        tokens.extend(change_stream(&mut changes_stream, &state));
+
+        // Allow trailing comma
+        optional_punct(&mut changes_stream, ',');
+    }
+    tokens
+}
+
+/// Generate the array assignment statement for a single byte->target mapping for one state.
+fn change_stream(iter: &mut Peekable<token_stream::IntoIter>, state: &TokenTree) -> TokenStream {
+    // Start of input byte range
+    let start = next_usize(iter);
+
+    // End of input byte range
+    let end = if optional_punct(iter, '.') {
+        // Read inclusive end of range
+        expect_punct(iter, '.');
+        expect_punct(iter, '=');
+        next_usize(iter)
+    } else {
+        // Without range, end is equal to start
+        start
+    };
+
+    // Separator between byte input range and output state
+    expect_punct(iter, '=');
+    expect_punct(iter, '>');
+
+    // Token stream with target state and action
+    let mut target_change_stream = next_group(iter).into_iter().peekable();
+
+    let mut tokens = quote!();
+    while target_change_stream.peek().is_some() {
+        // Target state/action for all bytes in the range
+        let (target_state, target_action) = target_change(&mut target_change_stream);
+
+        // Create a new entry for every byte in the range
+        for byte in start..=end {
+            // TODO: Force adding `State::` and `Action::`?
+            // TODO: Should we really use `pack` here without import?
+            tokens.extend(quote!(
+                state_changes[State::#state as usize][#byte] =
+                    pack(State::#target_state, Action::#target_action);
+            ));
+        }
+    }
+    tokens
+}
+
+/// Get next target state and action.
+fn target_change(iter: &mut Peekable<token_stream::IntoIter>) -> (TokenTree, TokenTree) {
+    let target_state = iter.next().unwrap();
+
+    // Separator between state and action
+    expect_punct(iter, ',');
+
+    let target_action = iter.next().unwrap();
+
+    (target_state, target_action)
+}
+
+/// Check if next token matches specific punctuation.
+fn optional_punct(iter: &mut Peekable<token_stream::IntoIter>, c: char) -> bool {
+    match iter.peek() {
+        Some(Punct(punct)) if punct.as_char() == c => iter.next().is_some(),
+        _ => false,
+    }
+}
+
+/// Ensure next token matches specific punctuation.
+///
+/// # Panics
+///
+/// Panics if the punctuation does not match.
+fn expect_punct(iter: &mut impl Iterator<Item = TokenTree>, c: char) {
+    match iter.next() {
+        Some(Punct(ref punct)) if punct.as_char() == c => (),
+        token => panic!("Expected punctuation '{}', but got {:?}", c, token),
+    }
+}
+
+/// Get next token as [`usize`].
+///
+/// # Panics
+///
+/// Panics if the next token is not a [`usize`] in hex or decimal literal format.
+fn next_usize(iter: &mut impl Iterator<Item = TokenTree>) -> usize {
+    match iter.next() {
+        Some(Literal(literal)) => {
+            let literal = literal.to_string();
+            if literal.starts_with("0x") {
+                usize::from_str_radix(&literal[2..], 16).unwrap()
+            } else {
+                usize::from_str_radix(&literal, 10).unwrap()
+            }
+        },
+        token => panic!("Expected literal, but got {:?}", token),
+    }
+}
+
+/// Get next token as [`Group`].
+///
+/// # Panics
+///
+/// Panics if the next token is not a [`Group`].
+fn next_group(iter: &mut impl Iterator<Item = TokenTree>) -> TokenStream {
+    match iter.next() {
+        Some(Group(group)) => group.stream(),
+        token => panic!("Expected group, but got {:?}", token),
+    }
+}