X-Git-Url: http://nitlanguage.org

diff --git a/lib/c.nit b/lib/c.nit
index 1d11d0d..ae1b875 100644
--- a/lib/c.nit
+++ b/lib/c.nit
@@ -23,10 +23,13 @@ intrude import standard::collection::array
 abstract class CArray[E]
 	super AbstractArrayRead[E]
 
+	# The corresponding C type
 	type NATIVE: NativeCArray
+
+	# Pointer to the real C array
 	var native_array: NATIVE is noinit
 
-	private init(length: Int) do self._length = length
+	private init(length: Int) is old_style_init do self._length = length
 
 	redef fun [](index)
 	do
@@ -35,6 +38,7 @@ abstract class CArray[E]
 		return native_array[index]
 	end
 
+	# Set `val` at `index`.
 	fun []=(index: Int, val: E)
 	do
 		assert not destroyed
@@ -42,7 +46,14 @@ abstract class CArray[E]
 		native_array[index] = val
 	end
 
+	# Was this instance destroyed?
+	#
+	# See `CArray::destroy`.
 	var destroyed = false
+
+	# Free used memory used by `native_array`.
+	#
+	# Also set `destroyed` to true.
 	fun destroy
 	do
 		if destroyed then return
@@ -54,10 +65,15 @@ end
 
 # A native C array, as in a pointer to the first element of the array
 extern class NativeCArray `{ void * `}
+
+	# Type of contained elements.
 	type E: nullable Object
 
-	fun [](index: E): E is abstract
-	fun []=(index: E, val: E) is abstract
+	# Get element at `index`.
+	fun [](index: Int): E is abstract
+
+	# Set `val` at `index`.
+	fun []=(index: Int, val: E) is abstract
 
 	# Return pointer to the address to the second element of this array
 	#
@@ -70,11 +86,21 @@ class CIntArray
 	super CArray[Int]
 	redef type NATIVE: NativeCIntArray
 
-	init(size: Int)
-	do
+	# Initialize a new CIntArray of `size` elements.
+	init(size: Int) is old_style_init do
 		native_array = new NativeCIntArray(size)
 		super size
 	end
+
+	# Build from an `Array[Int]`
+	new from(array: Array[Int])
+	do
+		var carray = new CIntArray(array.length)
+		for i in array.length.times do
+			carray[i] = array[i]
+		end
+		return carray
+	end
 end
 
 # An array of `int` in C (`int*`)
@@ -82,7 +108,45 @@ extern class NativeCIntArray `{ int* `}
 	super NativeCArray
 	redef type E: Int
 
+	# Initialize a new NativeCIntArray of `size` elements.
 	new(size: Int) `{ return calloc(size, sizeof(int)); `}
+
+	redef fun [](index) `{ return recv[index]; `}
+	redef fun []=(index, val) `{ recv[index] = val; `}
+
+	redef fun +(offset) `{ return recv + offset; `}
+end
+
+# Wrapper around an array of `unsigned char` in C (`unsigned char*`) with length and destroy state
+class CByteArray
+	super CArray[Int]
+	redef type NATIVE: NativeCByteArray
+
+	# Allocate a new array of `size`
+	init(size: Int) is old_style_init do
+		native_array = new NativeCByteArray(size)
+		super size
+	end
+
+	# Build from an `Array[Int]`
+	new from(array: Array[Int])
+	do
+		var carray = new CByteArray(array.length)
+		for i in array.length.times do
+			carray[i] = array[i]
+		end
+		return carray
+	end
+end
+
+# An array of `unsigned char` in C (`unsigned char*`)
+extern class NativeCByteArray `{ unsigned char* `}
+	super NativeCArray
+	redef type E: Int
+
+	# Allocate a new array of `size`
+	new(size: Int) `{ return calloc(size, sizeof(unsigned char)); `}
+
 	redef fun [](index) `{ return recv[index]; `}
 	redef fun []=(index, val) `{ recv[index] = val; `}