Merge pull request #71 from bramtayl/handle_null

handle C_NULL errors

src/libportaudio.jl

@@ -116,8 +116,14 @@ mutable struct PaHostApiInfo
     defaultOutputDevice::PaDeviceIndex
 end
 
-Pa_GetHostApiInfo(i) = unsafe_load(@locked ccall((:Pa_GetHostApiInfo, libportaudio),
-                                   Ptr{PaHostApiInfo}, (PaHostApiIndex,), i))
+function Pa_GetHostApiInfo(i)
+    result = @locked ccall((:Pa_GetHostApiInfo, libportaudio),
+        Ptr{PaHostApiInfo}, (PaHostApiIndex,), i)
+    if result == C_NULL
+        throw(BoundsError(Pa_GetHostApiInfo, i))
+    end
+    unsafe_load(result)
+end
 
 # Device Functions
 
@@ -136,8 +142,14 @@ end
 
 Pa_GetDeviceCount() = @locked ccall((:Pa_GetDeviceCount, libportaudio), PaDeviceIndex, ())
 
-Pa_GetDeviceInfo(i) = unsafe_load(@locked ccall((:Pa_GetDeviceInfo, libportaudio),
-                                 Ptr{PaDeviceInfo}, (PaDeviceIndex,), i))
+function Pa_GetDeviceInfo(i)
+    result = @locked ccall((:Pa_GetDeviceInfo, libportaudio),
+        Ptr{PaDeviceInfo}, (PaDeviceIndex,), i)
+    if result == C_NULL
+        throw(BoundsError(Pa_GetDeviceInfo, i))
+    end
+    unsafe_load(result)
+end
 
 Pa_GetDefaultInputDevice() = @locked ccall((:Pa_GetDefaultInputDevice, libportaudio),
                                    PaDeviceIndex, ())
@@ -260,7 +272,9 @@ end
 # function Pa_GetStreamInfo(stream::PaStream)
 #     infoptr = ccall((:Pa_GetStreamInfo, libportaudio), Ptr{PaStreamInfo},
 #             (PaStream, ), stream)
-#
+#     if infoptr == C_NULL
+#         error("Error getting stream info. Is the stream already closed?")
+#     end
 #     unsafe_load(infoptr)
 # end
 #

test/runtests.jl

@@ -1,7 +1,7 @@
 #!/usr/bin/env julia
 
 using PortAudio
-using PortAudio: Pa_GetDefaultInputDevice, Pa_GetDefaultOutputDevice, Pa_GetDeviceInfo, PortAudioDevice
+using PortAudio: Pa_GetDefaultInputDevice, Pa_GetDefaultOutputDevice, Pa_GetDeviceInfo, Pa_GetHostApiInfo, PortAudioDevice
 using Test
 using SampledSignals
 
@@ -17,6 +17,11 @@ using SampledSignals
     @testset "Can list devices without crashing" begin
         PortAudio.devices()
     end
+
+    @testset "Null errors" begin
+        @test_throws BoundsError Pa_GetDeviceInfo(-1)
+        @test_throws BoundsError Pa_GetHostApiInfo(-1)
+    end
 end
 
 if !isempty(PortAudio.devices())