Adding (sagittarius atomic) document

doc/sagittarius.md

@@ -1064,3 +1064,4 @@ The macro return the result of _expr_.
 * @[[sagittarius/debug.md](sagittarius/debug.md)]
 * @[[sagittarius/generators.md](sagittarius/generators.md)]
 * @[[sagittarius/crypto.md](sagittarius/crypto.md)]
+* @[[sagittarius/atomic.md](sagittarius/atomic.md)]

doc/sagittarius/atomic.md

@@ -0,0 +1,84 @@
+[§2] (sagittarius atomic) - Atomic operation {#lib.sagittarius.atomic}
+-------------
+
+###### [!Library] `(sagittarius atomic)` **[@since] `0.9.13`**
+
+This library provides atomic operation. The underlying implementation
+of this library can be either `stdatomic` from C11 or `libatomic_ops`.
+If the platform supports the first one, then that'd be chosen, otherwise
+the latter one.
+
+###### [!Function] `atomic?` _obj_
+
+Returns `#t` if the given _obj_ is an atomic object, otherwise `#f`.
+
+###### [!Function] `make-atomic` _obj_
+
+Creates a fresh atomic object whoes initial value is _obj_.
+
+###### [!Function] `atomic-fixnum?` _obj_
+
+Returns `#t` if the given _obj_ is an atomic fixnum object, otherwise `#f`.
+
+###### [!Function] `make-atomic-fixnum` (_n_ `fixnum?`)
+
+Creates a fresh atomic fixnum object whoes initial value is _n_.
+
+###### [!Function] `memory-order?` _obj_
+
+Returns `#t` if the given _obj_ is a fixnum and value of memory order.
+
+###### [!Constant] `*memory-order:relaxed*`
+###### [!Constant] `*memory-order:consume*`
+###### [!Constant] `*memory-order:acquire*`
+###### [!Constant] `*memory-order:release*`
+###### [!Constant] `*memory-order:acq-rel*`
+###### [!Constant] `*memory-order:seq-cst*`
+
+The memory order values. The meanings are the same as C11.
+
+If the `libatomic_ops` is used as underlying implementation, then it
+translate them with the best effort.
+
+###### [!Function] `atomic-load` (_a_ `atomic?`) :optional (_order_ `memory-order?`)
+
+Loads the current value of the given atomic of _a_.
+
+###### [!Function] `atomic-store!` (_a_ `atomic?`) _v_ :optional (_order_ `memory-order?`)
+
+Stores the given value _v_ into the atomic _a_.
+
+###### [!Function] `atomic-fixnum-load` (_a_ `atomic-fixnum?`) :optional (_order_ `memory-order?`)
+
+Loads the current value of the given atomic of _a_.
+
+###### [!Function] `atomic-fixnum-store!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+
+Stores the given value _n_ into the atomic _a_.
+The return value is unspecified.
+
+###### [!Function] `atomic-fixnum-add!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-sub!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-or!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-xor!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-and!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+
+Operates the addition, subtraction, bitwise or, bitwise xor and bitwise and
+against the value of atomic _a_ with given _n_ and updates the value of _a_.
+
+The return value is unspecified.
+
+###### [!Function] `atomic-exchange!` (_a_ `atomic?`) _v_ :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-exchange!` (_a_ `atomic-fixnum?`) (_n_ `fixnum?`) :optional (_order_ `memory-order?`)
+
+Exchange the value of _a_ with given _v_ or _n_ and returns the old value
+of _a_.
+
+###### [!Function] `atomic-compare-and-swap!` (_a_ `atomic?`) _v_ :optional (_order_ `memory-order?`)
+
+CAS operation.
+
+###### [!Function] `atomic-fixnum-inc!` (_a_ `atomic-fixnum?`) :optional (_order_ `memory-order?`)
+###### [!Function] `atomic-fixnum-dec!` (_a_ `atomic-fixnum?`) :optional (_order_ `memory-order?`)
+
+Increment or decrement the value of given _a_ and updates the value.