Rust cleanup (#1573)

* rust: formatting cleanup

* rust: explicitly mark as ISC license

* rust: use std::ffi C types instead of libc dependency

rust/example_printnets/src/lib.rs

@@ -8,7 +8,9 @@ pub extern "C" fn rust_example_printnets(ctx: &mut Context) {
         let driver = net.driver();
         println!("  {}:", ctx.name_of(name).to_str().unwrap());
         if let Some(driver) = driver {
-            let cell = driver.cell().map_or("(no cell)", |cell| ctx.name_of(cell.name()).to_str().unwrap());
+            let cell = driver.cell().map_or("(no cell)", |cell| {
+                ctx.name_of(cell.name()).to_str().unwrap()
+            });
             let port = ctx.name_of(driver.port()).to_str().unwrap();
             println!("    driver: {cell}.{port}");
         } else {

rust/nextpnr/Cargo.toml

@@ -2,6 +2,7 @@
 name = "nextpnr"
 version = "0.1.0"
 edition = "2024"
+license = "ISC"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -11,4 +12,3 @@ path = "src/lib.rs"
 crate-type = ["rlib"]
 
 [dependencies]
-libc = "0.2"

rust/nextpnr/src/lib.rs

@@ -1,6 +1,4 @@
-use std::{ffi::CStr, marker::PhantomData, sync::Mutex};
-
-use libc::c_char;
+use std::{ffi::{c_char, c_int, CStr, CString}, marker::PhantomData, sync::Mutex};
 
 #[derive(Clone, Copy)]
 #[repr(C)]
@@ -55,7 +53,7 @@ impl NetInfo {
     pub fn users(&self) -> NetUserIter<'_> {
         NetUserIter {
             iter: unsafe { npnr_context_net_user_iter(self) },
-            phantom_data: PhantomData
+            phantom_data: PhantomData,
         }
     }
 }
@@ -91,7 +89,7 @@ impl PortRef {
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 #[repr(transparent)]
-pub struct IdString(libc::c_int);
+pub struct IdString(c_int);
 
 /// A type representing a bel name.
 #[derive(Clone, Copy, PartialEq, Eq)]
@@ -163,9 +161,9 @@ impl WireId {
 #[repr(C)]
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub struct Loc {
-    pub x: libc::c_int,
-    pub y: libc::c_int,
-    pub z: libc::c_int,
+    pub x: c_int,
+    pub y: c_int,
+    pub z: c_int,
 }
 
 impl From<(i32, i32)> for Loc {
@@ -297,19 +295,28 @@ impl Context {
     #[must_use]
     pub fn bels(&self) -> BelIter<'_> {
         let iter = unsafe { npnr_context_get_bels(self) };
-        BelIter { iter, phantom_data: PhantomData }
+        BelIter {
+            iter,
+            phantom_data: PhantomData,
+        }
     }
 
     #[must_use]
     pub fn pips(&self) -> PipIter<'_> {
         let iter = unsafe { npnr_context_get_pips(self) };
-        PipIter { iter, phantom_data: PhantomData }
+        PipIter {
+            iter,
+            phantom_data: PhantomData,
+        }
     }
 
     #[must_use]
     pub fn wires(&self) -> WireIter<'_> {
         let iter = unsafe { npnr_context_get_wires(self) };
-        WireIter { iter, phantom_data: PhantomData }
+        WireIter {
+            iter,
+            phantom_data: PhantomData,
+        }
     }
 
     #[must_use]
@@ -337,8 +344,8 @@ impl Context {
 
     #[must_use]
     pub fn pip_direction(&self, pip: PipId) -> Loc {
-        let mut src = Loc{x: 0, y: 0, z: 0};
-        let mut dst = Loc{x: 0, y: 0, z: 0};
+        let mut src = Loc { x: 0, y: 0, z: 0 };
+        let mut dst = Loc { x: 0, y: 0, z: 0 };
 
         let mut pips = 0;
         for pip in self.get_uphill_pips(self.pip_src_wire(pip)) {
@@ -364,7 +371,11 @@ impl Context {
             dst.y /= pips;
         }
 
-        Loc{x: dst.x - src.x, y: dst.y - src.y, z: 0}
+        Loc {
+            x: dst.x - src.x,
+            y: dst.y - src.y,
+            z: 0,
+        }
     }
 
     #[must_use]
@@ -383,7 +394,7 @@ impl Context {
 
     #[must_use]
     pub fn id(&self, s: &str) -> IdString {
-        let s = std::ffi::CString::new(s).unwrap();
+        let s = CString::new(s).unwrap();
         unsafe { npnr_context_id(self, s.as_ptr()) }
     }
 
@@ -424,8 +435,8 @@ unsafe extern "C" {
     safe fn npnr_wireid_null() -> WireId;
     safe fn npnr_pipid_null() -> PipId;
 
-    fn npnr_context_get_grid_dim_x(ctx: &Context) -> libc::c_int;
-    fn npnr_context_get_grid_dim_y(ctx: &Context) -> libc::c_int;
+    fn npnr_context_get_grid_dim_x(ctx: &Context) -> c_int;
+    fn npnr_context_get_grid_dim_y(ctx: &Context) -> c_int;
     fn npnr_context_bind_bel(
         ctx: &mut Context,
         bel: BelId,
@@ -455,18 +466,14 @@ unsafe extern "C" {
     fn npnr_context_get_pip_delay(ctx: &Context, pip: PipId) -> f32;
     fn npnr_context_get_wire_delay(ctx: &Context, wire: WireId) -> f32;
     fn npnr_context_get_pip_location(ctx: &Context, pip: PipId) -> Loc;
-    fn npnr_context_check_pip_avail_for_net(
-        ctx: &Context,
-        pip: PipId,
-        net: &NetInfo,
-    ) -> bool;
+    fn npnr_context_check_pip_avail_for_net(ctx: &Context, pip: PipId, net: &NetInfo) -> bool;
 
     fn npnr_context_check(ctx: &Context);
     fn npnr_context_debug(ctx: &Context) -> bool;
     fn npnr_context_id(ctx: &Context, s: *const c_char) -> IdString;
-    fn npnr_context_name_of(ctx: &Context, s: IdString) -> *const libc::c_char;
-    fn npnr_context_name_of_pip(ctx: &Context, pip: PipId) -> *const libc::c_char;
-    fn npnr_context_name_of_wire(ctx: &Context, wire: WireId) -> *const libc::c_char;
+    fn npnr_context_name_of(ctx: &Context, s: IdString) -> *const c_char;
+    fn npnr_context_name_of_pip(ctx: &Context, pip: PipId) -> *const c_char;
+    fn npnr_context_name_of_wire(ctx: &Context, wire: WireId) -> *const c_char;
     fn npnr_context_verbose(ctx: &Context) -> bool;
 
     fn npnr_context_get_netinfo_source_wire(ctx: &Context, net: &NetInfo) -> WireId;
@@ -483,9 +490,9 @@ unsafe extern "C" {
     fn npnr_netinfo_udata_set(net: &mut NetInfo, value: NetIndex);
 
     fn npnr_portref_cell(port: &PortRef) -> Option<&CellInfo>;
-    fn npnr_portref_port(port: &PortRef) -> libc::c_int;
+    fn npnr_portref_port(port: &PortRef) -> c_int;
     fn npnr_cellinfo_get_location(cell: &CellInfo) -> Loc;
-    fn npnr_cellinfo_name(cell: &CellInfo) -> libc::c_int;
+    fn npnr_cellinfo_name(cell: &CellInfo) -> c_int;
 
     fn npnr_context_get_pips_downhill(ctx: &Context, wire: WireId) -> &mut RawDownhillIter;
     fn npnr_delete_downhill_iter(iter: &mut RawDownhillIter);
@@ -520,14 +527,14 @@ unsafe extern "C" {
     fn npnr_context_net_iter(ctx: &Context) -> &mut RawNetIter;
     fn npnr_delete_net_iter(iter: &mut RawNetIter);
     fn npnr_inc_net_iter(iter: &mut RawNetIter);
-    fn npnr_deref_net_iter_first(iter: &RawNetIter) -> libc::c_int;
+    fn npnr_deref_net_iter_first(iter: &RawNetIter) -> c_int;
     fn npnr_deref_net_iter_second(iter: &RawNetIter) -> &mut NetInfo;
     fn npnr_is_net_iter_done(iter: &RawNetIter) -> bool;
 
     fn npnr_context_cell_iter(ctx: &Context) -> &mut RawCellIter;
     fn npnr_delete_cell_iter(iter: &mut RawCellIter);
     fn npnr_inc_cell_iter(iter: &mut RawCellIter);
-    fn npnr_deref_cell_iter_first(iter: &mut RawCellIter) -> libc::c_int;
+    fn npnr_deref_cell_iter_first(iter: &mut RawCellIter) -> c_int;
     fn npnr_deref_cell_iter_second(iter: &mut RawCellIter) -> &mut CellInfo;
     fn npnr_is_cell_iter_done(iter: &mut RawCellIter) -> bool;
 
@@ -535,7 +542,7 @@ unsafe extern "C" {
     fn npnr_delete_net_user_iter(iter: &mut RawNetUserIter);
     fn npnr_inc_net_user_iter(iter: &mut RawNetUserIter);
     fn npnr_deref_net_user_iter_cell(iter: &mut RawNetUserIter) -> &mut CellInfo;
-    fn npnr_deref_net_user_iter_port(iter: &mut RawNetUserIter) -> libc::c_int;
+    fn npnr_deref_net_user_iter_port(iter: &mut RawNetUserIter) -> c_int;
     fn npnr_is_net_user_iter_done(iter: &mut RawNetUserIter) -> bool;
 }
 
@@ -851,4 +858,3 @@ macro_rules! log_error {
         unsafe { crate::npnr::npnr_log_error(s.as_ptr()); }
     };
 }
-