Improve signatures and error reporting for a few audio utility functions.

git-svn-id: http://nohands.svn.sourceforge.net/svnroot/nohands/trunk@47 126591fb-c623-4b62-a76d-97a8e4f34109

2 files changed, 36 insertions, 13 deletions

diff --git a/include/libhfp/soundio.h b/include/libhfp/soundio.h
index 99fb390..1ccc9b1 100644
--- a/include/libhfp/soundio.h
+++ b/include/libhfp/soundio.h
@@ -886,9 +886,14 @@ public:
  * @c false to ignore data streaming upward.
  * @param[in] dn Set to @c true to snoop audio data streaming downward,
  * @c false to ignore data streaming downward.
+ * @param[out] error Error information structure.  If this method
+ * fails and returns @c 0, and @em error is not 0, @em error
+ * will be filled out with information on the cause of the failure.
+ * Currently, the only reason for failure of this function is a memory
+ * allocation failure.
  *
  * @return A newly constructed snoop filter configured with the target
- * endpoint, or @c 0 on memory allocation failure.
+ * endpoint, or @c 0 on error
  *
  * @note The snoop filter does not perform any life cycle management on
  * the specified slave endpoint.  Clients are responsible for managing the
@@ -896,7 +901,8 @@ public:
  * snoop filter before destroying the slave endpoint.
  */
 extern SoundIoFilter *SoundIoCreateSnooper(SoundIo *target,
-					   bool up = true, bool dn = true);
+					   bool up = true, bool dn = true,
+					   ErrorInfo *error = 0);
 
 
 /**
@@ -952,6 +958,9 @@ public:
  *
  * @param[in] ei Pointer to dispatcher interface object for the environment.
  * This is used for logging errors.
+ * @param[out] error Error information structure.  If this method
+ * fails and returns @c 0, and @em error is not 0, @em error
+ * will be filled out with information on the cause of the failure.
  *
  * To use this filter:
  * -# Instantaite it with this function.
@@ -965,9 +974,10 @@ public:
  * configure it, see SoundIoSpeexProps and SoundIoFltSpeex::Configure().
  *
  * @return A newly constructed, unconfigured SoundIoFltSpeex object,
- * or NULL on error.
+ * or @c 0 on error.
  */
-SoundIoFltSpeex *SoundIoFltCreateSpeex(DispatchInterface *ei);
+extern SoundIoFltSpeex *SoundIoFltCreateSpeex(DispatchInterface *ei,
+					      ErrorInfo *error = 0);
 
 
 /**
diff --git a/libhfp/soundio-util.cpp b/libhfp/soundio-util.cpp
index 6137497..0d1bf3b 100644
--- a/libhfp/soundio-util.cpp
+++ b/libhfp/soundio-util.cpp
@@ -588,14 +588,13 @@ SoundIoCreateFileHandler(DispatchInterface *ei,
 				error->SetNoMem();
 		}
 	}
-	return siop;
 #endif
 
-	if (error)
+	if (!siop && error && !error->IsSet())
 		error->Set(LIBHFP_ERROR_SUBSYS_SOUNDIO,
 			   LIBHFP_ERROR_SOUNDIO_NOT_SUPPORTED,
 			   "Support for libaudiofile omitted");
-	return 0;
+	return siop;
 }
 
 
@@ -756,11 +755,16 @@ public:
 };
 
 SoundIoFilter *
-SoundIoCreateSnooper(SoundIo *target, bool up, bool dn)
+SoundIoCreateSnooper(SoundIo *target, bool up, bool dn, ErrorInfo *error)
 {
+	SoundIoFilter *fltp;
+
 	assert(target);
 	assert(up || dn);
-	return new SoundIoSnooper(target, up, dn);
+	fltp = new SoundIoSnooper(target, up, dn);
+	if (!fltp && error)
+		error->SetNoMem();
+	return fltp;
 }
 
 
@@ -997,13 +1001,22 @@ public:
 };
 #endif /* defined(USE_SPEEXDSP) */
 
-SoundIoFltSpeex *SoundIoFltCreateSpeex(DispatchInterface *ei)
+SoundIoFltSpeex *SoundIoFltCreateSpeex(DispatchInterface *ei,
+				       ErrorInfo *error)
 {
+	SoundIoFltSpeex *fltp;
+
 #if defined(USE_SPEEXDSP)
-	return new SoundIoFltSpeexImpl(ei);
-#else
-	return 0;
+	fltp = new SoundIoFltSpeexImpl(ei);
+	if (!fltp && error)
+		error->SetNoMem();
 #endif
+
+	if (!fltp && error && !error->IsSet())
+		error->Set(LIBHFP_ERROR_SUBSYS_SOUNDIO,
+			   LIBHFP_ERROR_SOUNDIO_NOT_SUPPORTED,
+			   "Support for speexdsp omitted");
+	return fltp;
 }