Port bolp and eolp to rust

rust_src/src/buffers.rs

@@ -41,6 +41,11 @@ impl LispBufferRef {
         unsafe { (*self.text).gpt_byte }
     }
 
+    #[inline]
+    pub fn gap_size(&self) -> ptrdiff_t {
+        unsafe { (*self.text).gap_size }
+    }
+
     #[inline]
     pub fn gap_end_addr(&self) -> *mut c_uchar {
         unsafe {
@@ -91,6 +96,19 @@ impl LispBufferRef {
     pub fn is_live(self) -> bool {
         LispObject::from_raw(self.name).is_not_nil()
     }
+
+    #[inline]
+    pub fn fetch_byte(&self, n: ptrdiff_t) -> u8 {
+        let base_addr =
+            if n  >= self.gpt_byte() {
+                self.gap_size()
+            } else {
+                0
+            };
+        let byte_addr = (base_addr + n +
+                         self.beg_addr() as ptrdiff_t - self.beg_byte()) as *const u8;
+        unsafe {(*byte_addr) as u8 }
+    }
 }
 
 impl LispObject {

rust_src/src/editfns.rs

@@ -49,3 +49,22 @@ pub fn bobp() -> LispObject {
     let buffer_ref = ThreadState::current_buffer();
     LispObject::from_bool(buffer_ref.pt == buffer_ref.begv)
 }
+
+/// Return t if point is at the beginning of a line.
+#[lisp_fn]
+pub fn bolp() -> LispObject {
+    let buffer_ref = ThreadState::current_buffer();
+    let pt_byte = buffer_ref.pt_byte - 1;
+    LispObject::from_bool(buffer_ref.pt == buffer_ref.begv ||
+                          buffer_ref.fetch_byte(pt_byte) as char == '\n')
+}
+
+/// Return t if point is at the end of a line.
+///`End of a line' includes point being at the end of the buffer.
+#[lisp_fn]
+pub fn eolp() -> LispObject {
+    let buffer_ref = ThreadState::current_buffer();
+    let pt_byte = buffer_ref.pt_byte;
+    LispObject::from_bool(buffer_ref.pt == buffer_ref.zv() ||
+                          buffer_ref.fetch_byte(pt_byte) as char == '\n')
+}

rust_src/src/lib.rs

@@ -162,6 +162,8 @@ pub use multibyte::str_to_unibyte;
 
 // Used in window.c, macros.c
 pub use interactive::Fprefix_numeric_value;
+pub use editfns::Fbolp;
+pub use editfns::Feolp;
 
 extern "C" {
     fn defsubr(sname: *const Lisp_Subr);
@@ -319,5 +321,7 @@ pub extern "C" fn rust_init_syms() {
         defsubr(&*editfns::Sbuffer_size);
         defsubr(&*editfns::Seobp);
         defsubr(&*editfns::Sbobp);
+        defsubr(&*editfns::Sbolp);
+        defsubr(&*editfns::Seolp);
     }
 }

src/editfns.c

@@ -1167,25 +1167,6 @@ At the beginning of the buffer or accessible region, return 0.  */)
   return temp;
 }
 
-DEFUN ("bolp", Fbolp, Sbolp, 0, 0, 0,
-       doc: /* Return t if point is at the beginning of a line.  */)
-  (void)
-{
-  if (PT == BEGV || FETCH_BYTE (PT_BYTE - 1) == '\n')
-    return Qt;
-  return Qnil;
-}
-
-DEFUN ("eolp", Feolp, Seolp, 0, 0, 0,
-       doc: /* Return t if point is at the end of a line.
-`End of a line' includes point being at the end of the buffer.  */)
-  (void)
-{
-  if (PT == ZV || FETCH_BYTE (PT_BYTE) == '\n')
-    return Qt;
-  return Qnil;
-}
-
 DEFUN ("char-after", Fchar_after, Schar_after, 0, 1, 0,
        doc: /* Return character in current buffer at position POS.
 POS is an integer or a marker and defaults to point.
@@ -5409,8 +5390,6 @@ functions if all the text being accessed has this property.  */);
   defsubr (&Sposition_bytes);
   defsubr (&Sbyte_to_position);
 
-  defsubr (&Sbolp);
-  defsubr (&Seolp);
   defsubr (&Sfollowing_char);
   defsubr (&Sprevious_char);
   defsubr (&Schar_after);