Merge pull request #76 from krrutkow/master

Fix bug with statically-sized arrays as function argument

Project.toml

@@ -1,7 +1,7 @@
 name = "CBinding"
 uuid = "d43a6710-96b8-4a2d-833c-c424785e5374"
 authors = ["Keith Rutkowski <[email protected]>"]
-version = "1.0.4"
+version = "1.0.5"
 
 [deps]
 Clang_jll = "0ee61d77-7f21-5576-8119-9fcc46b10100"

README.md

@@ -534,6 +534,10 @@ Therefore, attaching other methods to a bound C function is not possible.
 It is also sometimes necessary to use the `c"..."` mangled names directly in Julia (for instance in the REPL help mode).
 Until consistent, universal support for the string macro is available, the mangled names can be used directly as `var"c\"...\""`, like `help?> var"c\"struct Y\""`.
 
+When a C function has a statically-sized array as an argument in its signature, the semantics of C is to treat the argument as a pointer instead.
+Therefore, the statically-sized array in the binding signature will be lowered to a pointer for the underlying `ccall`.
+A user can then pass any argument (array, pointer, etc.) that is compatible with a pointer argument type (not the anticipated statically-sized array type).
+
 
 # Some helpful tips
 

src/arrays.jl

@@ -29,6 +29,7 @@ Base.size(::Type{CA}) where {T, N, CA<:Carrays{T, N}} = (N,)
 Base.length(::Type{CA}) where {T, N, CA<:Carrays{T, N}} = N
 Base.eltype(::Type{CA}) where {T, N, CA<:Carrays{T, N}} = T
 Base.convert(::Type{CA}, t::Tuple) where {CA<:Carray} = CA(t...)
+Base.convert(::Type{CA}, v::Vector) where {CA<:Carray} = CA(v...)
 
 Base.convert(::Type{CA}, str::String) where {T<:Union{Int8, UInt8, Cconst{Int8}, Cconst{UInt8}}, CA<:Carray{T}} = CA(str...)
 Base.convert(::Type{String}, ca::Carray{T}) where {T<:Union{Int8, UInt8, Cconst{Int8}, Cconst{UInt8}}} = String(map(t -> reinterpret(UInt8, convert(unqualifiedtype(T), t)), collect(ca)))

src/functions.jl

@@ -34,7 +34,11 @@ cconvert_default(::Type{T}) where {E, T<:AbstractArray{E}} = Cptr{E}
 		$(func <: Cptr ? :(Core.Intrinsics.bitcast(Ptr{Cvoid}, func)) : lib isa Symbol ? :(($(QuoteNode(name)), $(String(lib)))) : QuoteNode(name)),
 		$((conv isa Symbol ? (conv,) : ())...),
 		$(retT),
-		($(((argT <: Cvariadic ? :(Ptr{Cvoid}...) : argT) for argT in argTs)...),),
+		($(((
+			argT <: Cvariadic ? :(Ptr{Cvoid}...) :
+			argT <: Carray ? Cptr{eltype(argT)} :  # statically sized arrays (even when typedef-ed) are passed by pointer
+			argT
+		) for argT in argTs)...),),
 		$((:(args[$(i)]) for i in eachindex(args))...)
 	))
 end