Index: tests/src/io/base-source_custom.h
===================================================================
--- tests/src/io/base-source_custom.h	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
+++ tests/src/io/base-source_custom.h	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
@@ -0,0 +1,125 @@
+// this should be included *after* custom functions have been defined
+
+#ifndef aubio_source_custom
+#define aubio_source_custom "undefined"
+#endif /* aubio_source_custom */
+
+#ifdef HAVE_AUBIO_SOURCE_CUSTOM
+int test_wrong_params(void);
+
+int base_main(int argc, char **argv)
+{
+  uint_t err = 0;
+  if (argc < 2) {
+    PRINT_ERR("not enough arguments, running tests\n");
+    err = test_wrong_params();
+    PRINT_MSG("read a wave file as a mono vector\n");
+    PRINT_MSG("usage: %s <source_path> [samplerate] [hop_size]\n", argv[0]);
+    PRINT_MSG("examples:\n");
+    PRINT_MSG(" - read file.wav at original samplerate\n");
+    PRINT_MSG("       %s file.wav\n", argv[0]);
+    PRINT_MSG(" - read file.wav at 32000Hz\n");
+    PRINT_MSG("       %s file.aif 32000\n", argv[0]);
+    PRINT_MSG(" - read file.wav at original samplerate with 4096 blocks\n");
+    PRINT_MSG("       %s file.wav 0 4096 \n", argv[0]);
+    return err;
+  }
+
+  uint_t samplerate = 0;
+  uint_t hop_size = 256;
+  uint_t n_frames = 0, read = 0;
+  if ( argc >= 3 ) samplerate = atoi(argv[2]);
+  if ( argc >= 4 ) hop_size = atoi(argv[3]);
+
+  char_t *source_path = argv[1];
+
+  aubio_source_custom_t * s =
+    new_aubio_source_custom(source_path, samplerate, hop_size);
+  fvec_t *vec = new_fvec(hop_size);
+  if (!s || !vec) { err = 1; goto beach; }
+
+  uint_t n_frames_expected = aubio_source_custom_get_duration(s);
+
+  samplerate = aubio_source_custom_get_samplerate(s);
+
+  do {
+    aubio_source_custom_do(s, vec, &read);
+    fvec_print (vec);
+    n_frames += read;
+  } while ( read == hop_size );
+
+  PRINT_MSG("read %d frames (expected %d) at %dHz (%d blocks) from %s\n",
+            n_frames, n_frames_expected, samplerate, n_frames / hop_size,
+            source_path);
+
+  // close the file (optional)
+  aubio_source_custom_close(s);
+
+beach:
+  if (vec)
+    del_fvec(vec);
+  if (s)
+    del_aubio_source_custom(s);
+  return err;
+}
+
+int test_wrong_params(void)
+{
+  char_t *uri = DEFINEDSTRING(AUBIO_TESTS_SOURCE);
+  uint_t samplerate = 44100;
+  uint_t hop_size = 512;
+  uint_t channels, read = 0;
+  fvec_t *vec;
+  fmat_t *mat;
+  aubio_source_custom_t *s;
+
+  if (new_aubio_source_custom(0,    samplerate, hop_size)) return 1;
+  if (new_aubio_source_custom('\0', samplerate, hop_size)) return 1;
+  if (new_aubio_source_custom(uri,          -1, hop_size)) return 1;
+  if (new_aubio_source_custom(uri,           0,        0)) return 1;
+
+  s = new_aubio_source_custom(uri, samplerate, hop_size);
+  if (!s) return 1;
+  channels = aubio_source_custom_get_channels(s);
+
+  // vector to read downmixed samples
+  vec = new_fvec(hop_size);
+  // matrix to read individual channels
+  mat = new_fmat(channels, hop_size);
+
+  if (aubio_source_custom_get_samplerate(s) != samplerate) return 1;
+
+  // read first hop_size frames
+  aubio_source_custom_do(s, vec, &read);
+  if (read != hop_size) return 1;
+
+  // seek to 0
+  if(aubio_source_custom_seek(s, 0)) return 1;
+
+  // read again as multiple channels
+  aubio_source_custom_do_multi(s, mat, &read);
+  if (read != hop_size) return 1;
+
+  // close the file (optional)
+  aubio_source_custom_close(s);
+  // test closing the file a second time
+  aubio_source_custom_close(s);
+
+  del_aubio_source_custom(s);
+  del_fmat(mat);
+  del_fvec(vec);
+
+  return run_on_default_source(base_main);
+}
+
+#else /* HAVE_AUBIO_SOURCE_CUSTOM */
+
+int base_main(int argc, char** argv)
+{
+  PRINT_ERR("aubio was not compiled with aubio_source_"
+          aubio_source_custom ", failed running %s with %d args\n",
+          argv[0], argc);
+  return 0;
+}
+
+#endif /* HAVE_AUBIO_SOURCE_CUSTOM */
Index: tests/src/io/test-source_apple_audio.c
===================================================================
--- tests/src/io/test-source_apple_audio.c	(revision 423a4272b831482a4c088fd035a16d132ab11ddc)
+++ tests/src/io/test-source_apple_audio.c	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
@@ -2,4 +2,23 @@
 #include <aubio.h>
 #include "utils_tests.h"
+
+#define aubio_source_custom "apple_audio"
+
+#ifdef HAVE_SOURCE_APPLE_AUDIO
+#define HAVE_AUBIO_SOURCE_CUSTOM
+#define aubio_source_custom_t aubio_source_apple_audio_t
+#define new_aubio_source_custom new_aubio_source_apple_audio
+#define del_aubio_source_custom del_aubio_source_apple_audio
+#define aubio_source_custom_get_samplerate aubio_source_apple_audio_get_samplerate
+#define aubio_source_custom_get_duration aubio_source_apple_audio_get_duration
+#define aubio_source_custom_do aubio_source_apple_audio_do
+#define aubio_source_custom_do_multi aubio_source_apple_audio_do_multi
+#define aubio_source_custom_seek aubio_source_apple_audio_seek
+#define aubio_source_custom_close aubio_source_apple_audio_close
+#define aubio_source_custom_get_channels aubio_source_apple_audio_get_channels
+#define aubio_source_custom_get_samplerate aubio_source_apple_audio_get_samplerate
+#endif /* HAVE_SOURCE_APPLE_AUDIO */
+
+#include "base-source_custom.h"
 
 // this file uses the unstable aubio api, please use aubio_source instead
@@ -8,56 +27,4 @@
 int main (int argc, char **argv)
 {
-  uint_t err = 0;
-  if (argc < 2) {
-    PRINT_ERR("not enough arguments, running tests\n");
-    err = run_on_default_source(main);
-    PRINT_MSG("read a wave file as a mono vector\n");
-    PRINT_MSG("usage: %s <source_path> [samplerate] [hop_size]\n", argv[0]);
-    PRINT_MSG("examples:\n");
-    PRINT_MSG(" - read file.wav at original samplerate\n");
-    PRINT_MSG("       %s file.wav\n", argv[0]);
-    PRINT_MSG(" - read file.aif at 32000Hz\n");
-    PRINT_MSG("       %s file.aif 32000\n", argv[0]);
-    PRINT_MSG(" - read file.mp3 at original samplerate with 4096 blocks\n");
-    PRINT_MSG("       %s file.mp3 0 4096 \n", argv[0]);
-    return err;
-  }
-
-#if HAVE_SOURCE_APPLE_AUDIO
-  uint_t samplerate = 0;
-  uint_t hop_size = 256;
-  uint_t n_frames = 0, read = 0;
-  if ( argc >= 3 ) samplerate = atoi(argv[2]);
-  if ( argc >= 4 ) hop_size = atoi(argv[3]);
-
-  char_t *source_path = argv[1];
-
-
-  aubio_source_apple_audio_t * s =
-    new_aubio_source_apple_audio(source_path, samplerate, hop_size);
-  if (!s) { err = 1; goto beach; }
-  fvec_t *vec = new_fvec(hop_size);
-
-  uint_t n_frames_expected = aubio_source_apple_audio_get_duration(s);
-
-  samplerate = aubio_source_apple_audio_get_samplerate(s);
-
-  do {
-    aubio_source_apple_audio_do(s, vec, &read);
-    fvec_print (vec);
-    n_frames += read;
-  } while ( read == hop_size );
-
-  PRINT_MSG("read %d frames (expected %d) at %dHz (%d blocks) from %s\n",
-            n_frames, n_frames_expected, samplerate, n_frames / hop_size,
-            source_path);
-
-  del_fvec (vec);
-  del_aubio_source_apple_audio (s);
-beach:
-#else /* HAVE_SOURCE_APPLE_AUDIO */
-  err = 0;
-  PRINT_ERR("aubio was not compiled with aubio_source_apple_audio\n");
-#endif /* HAVE_SOURCE_APPLE_AUDIO */
-  return err;
+  return base_main(argc, argv);
 }
Index: tests/src/io/test-source_avcodec.c
===================================================================
--- tests/src/io/test-source_avcodec.c	(revision 423a4272b831482a4c088fd035a16d132ab11ddc)
+++ tests/src/io/test-source_avcodec.c	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
@@ -2,4 +2,23 @@
 #include <aubio.h>
 #include "utils_tests.h"
+
+#define aubio_source_custom "avcodec"
+
+#ifdef HAVE_LIBAV
+#define HAVE_AUBIO_SOURCE_CUSTOM
+#define aubio_source_custom_t aubio_source_avcodec_t
+#define new_aubio_source_custom new_aubio_source_avcodec
+#define del_aubio_source_custom del_aubio_source_avcodec
+#define aubio_source_custom_get_samplerate aubio_source_avcodec_get_samplerate
+#define aubio_source_custom_get_duration aubio_source_avcodec_get_duration
+#define aubio_source_custom_do aubio_source_avcodec_do
+#define aubio_source_custom_do_multi aubio_source_avcodec_do_multi
+#define aubio_source_custom_seek aubio_source_avcodec_seek
+#define aubio_source_custom_close aubio_source_avcodec_close
+#define aubio_source_custom_get_channels aubio_source_avcodec_get_channels
+#define aubio_source_custom_get_samplerate aubio_source_avcodec_get_samplerate
+#endif /* HAVE_LIBAV */
+
+#include "base-source_custom.h"
 
 // this file uses the unstable aubio api, please use aubio_source instead
@@ -8,56 +27,4 @@
 int main (int argc, char **argv)
 {
-  uint_t err = 0;
-  if (argc < 2) {
-    PRINT_ERR("not enough arguments, running tests\n");
-    err = run_on_default_source(main);
-    PRINT_MSG("read a wave file as a mono vector\n");
-    PRINT_MSG("usage: %s <source_path> [samplerate] [hop_size]\n", argv[0]);
-    PRINT_MSG("examples:\n");
-    PRINT_MSG(" - read file.wav at original samplerate\n");
-    PRINT_MSG("       %s file.wav\n", argv[0]);
-    PRINT_MSG(" - read file.wav at 32000Hz\n");
-    PRINT_MSG("       %s file.aif 32000\n", argv[0]);
-    PRINT_MSG(" - read file.wav at original samplerate with 4096 blocks\n");
-    PRINT_MSG("       %s file.wav 0 4096 \n", argv[0]);
-    return err;
-  }
-
-#ifdef HAVE_LIBAV
-  uint_t samplerate = 0;
-  uint_t hop_size = 256;
-  uint_t n_frames = 0, read = 0;
-  if ( argc >= 3 ) samplerate = atoi(argv[2]);
-  if ( argc >= 4 ) hop_size = atoi(argv[3]);
-
-  char_t *source_path = argv[1];
-
-
-  aubio_source_avcodec_t * s =
-    new_aubio_source_avcodec(source_path, samplerate, hop_size);
-  if (!s) { err = 1; goto beach; }
-  fvec_t *vec = new_fvec(hop_size);
-
-  uint_t n_frames_expected = aubio_source_avcodec_get_duration(s);
-
-  samplerate = aubio_source_avcodec_get_samplerate(s);
-
-  do {
-    aubio_source_avcodec_do(s, vec, &read);
-    fvec_print (vec);
-    n_frames += read;
-  } while ( read == hop_size );
-
-  PRINT_MSG("read %d frames (expected %d) at %dHz (%d blocks) from %s\n",
-            n_frames, n_frames_expected, samplerate, n_frames / hop_size,
-            source_path);
-
-  del_fvec (vec);
-  del_aubio_source_avcodec (s);
-beach:
-#else /* HAVE_LIBAV */
-  err = 0;
-  PRINT_ERR("aubio was not compiled with aubio_source_avcodec\n");
-#endif /* HAVE_LIBAV */
-  return err;
+  return base_main(argc, argv);
 }
Index: tests/src/io/test-source_sndfile.c
===================================================================
--- tests/src/io/test-source_sndfile.c	(revision 423a4272b831482a4c088fd035a16d132ab11ddc)
+++ tests/src/io/test-source_sndfile.c	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
@@ -2,4 +2,23 @@
 #include <aubio.h>
 #include "utils_tests.h"
+
+#define aubio_source_custom "sndfile"
+
+#ifdef HAVE_SNDFILE
+#define HAVE_AUBIO_SOURCE_CUSTOM
+#define aubio_source_custom_t aubio_source_sndfile_t
+#define new_aubio_source_custom new_aubio_source_sndfile
+#define del_aubio_source_custom del_aubio_source_sndfile
+#define aubio_source_custom_get_samplerate aubio_source_sndfile_get_samplerate
+#define aubio_source_custom_get_duration aubio_source_sndfile_get_duration
+#define aubio_source_custom_do aubio_source_sndfile_do
+#define aubio_source_custom_do_multi aubio_source_sndfile_do_multi
+#define aubio_source_custom_seek aubio_source_sndfile_seek
+#define aubio_source_custom_close aubio_source_sndfile_close
+#define aubio_source_custom_get_channels aubio_source_sndfile_get_channels
+#define aubio_source_custom_get_samplerate aubio_source_sndfile_get_samplerate
+#endif /* HAVE_LIBAV */
+
+#include "base-source_custom.h"
 
 // this file uses the unstable aubio api, please use aubio_source instead
@@ -8,56 +27,4 @@
 int main (int argc, char **argv)
 {
-  uint_t err = 0;
-  if (argc < 2) {
-    PRINT_ERR("not enough arguments, running tests\n");
-    err = run_on_default_source(main);
-    PRINT_MSG("read a wave file as a mono vector\n");
-    PRINT_MSG("usage: %s <source_path> [samplerate] [hop_size]\n", argv[0]);
-    PRINT_MSG("examples:\n");
-    PRINT_MSG(" - read file.wav at original samplerate\n");
-    PRINT_MSG("       %s file.wav\n", argv[0]);
-    PRINT_MSG(" - read file.wav at 32000Hz\n");
-    PRINT_MSG("       %s file.aif 32000\n", argv[0]);
-    PRINT_MSG(" - read file.wav at original samplerate with 4096 blocks\n");
-    PRINT_MSG("       %s file.wav 0 4096 \n", argv[0]);
-    return err;
-  }
-
-#ifdef HAVE_SNDFILE
-  uint_t samplerate = 0;
-  uint_t hop_size = 256;
-  uint_t n_frames = 0, read = 0;
-  if ( argc >= 3 ) samplerate = atoi(argv[2]);
-  if ( argc >= 4 ) hop_size = atoi(argv[3]);
-
-  char_t *source_path = argv[1];
-
-
-  aubio_source_sndfile_t * s =
-    new_aubio_source_sndfile(source_path, samplerate, hop_size);
-  if (!s) { err = 1; goto beach; }
-  fvec_t *vec = new_fvec(hop_size);
-
-  uint_t n_frames_expected = aubio_source_sndfile_get_duration(s);
-
-  samplerate = aubio_source_sndfile_get_samplerate(s);
-
-  do {
-    aubio_source_sndfile_do(s, vec, &read);
-    fvec_print (vec);
-    n_frames += read;
-  } while ( read == hop_size );
-
-  PRINT_MSG("read %d frames (expected %d) at %dHz (%d blocks) from %s\n",
-            n_frames, n_frames_expected, samplerate, n_frames / hop_size,
-            source_path);
-
-  del_fvec (vec);
-  del_aubio_source_sndfile (s);
-beach:
-#else
-  err = 0;
-  PRINT_ERR("aubio was not compiled with aubio_source_sndfile\n");
-#endif /* HAVE_SNDFILE */
-  return err;
+  return base_main(argc, argv);
 }
Index: tests/src/io/test-source_wavread.c
===================================================================
--- tests/src/io/test-source_wavread.c	(revision 423a4272b831482a4c088fd035a16d132ab11ddc)
+++ tests/src/io/test-source_wavread.c	(revision 7735d0634a5c8e7805c57414a32fc7d31e791c13)
@@ -2,4 +2,23 @@
 #include <aubio.h>
 #include "utils_tests.h"
+
+#define aubio_source_custom "wavread"
+
+#ifdef HAVE_WAVREAD
+#define HAVE_AUBIO_SOURCE_CUSTOM
+#define aubio_source_custom_t aubio_source_wavread_t
+#define new_aubio_source_custom new_aubio_source_wavread
+#define del_aubio_source_custom del_aubio_source_wavread
+#define aubio_source_custom_get_samplerate aubio_source_wavread_get_samplerate
+#define aubio_source_custom_get_duration aubio_source_wavread_get_duration
+#define aubio_source_custom_do aubio_source_wavread_do
+#define aubio_source_custom_do_multi aubio_source_wavread_do_multi
+#define aubio_source_custom_seek aubio_source_wavread_seek
+#define aubio_source_custom_close aubio_source_wavread_close
+#define aubio_source_custom_get_channels aubio_source_wavread_get_channels
+#define aubio_source_custom_get_samplerate aubio_source_wavread_get_samplerate
+#endif /* HAVE_WAVREAD */
+
+#include "base-source_custom.h"
 
 // this file uses the unstable aubio api, please use aubio_source instead
@@ -8,56 +27,4 @@
 int main (int argc, char **argv)
 {
-  uint_t err = 0;
-  if (argc < 2) {
-    PRINT_ERR("not enough arguments, running tests\n");
-    err = run_on_default_source(main);
-    PRINT_MSG("read a wave file as a mono vector\n");
-    PRINT_MSG("usage: %s <source_path> [samplerate] [hop_size]\n", argv[0]);
-    PRINT_MSG("examples:\n");
-    PRINT_MSG(" - read file.wav at original samplerate\n");
-    PRINT_MSG("       %s file.wav\n", argv[0]);
-    PRINT_MSG(" - read file.wav at 32000Hz\n");
-    PRINT_MSG("       %s file.aif 32000\n", argv[0]);
-    PRINT_MSG(" - read file.wav at original samplerate with 4096 blocks\n");
-    PRINT_MSG("       %s file.wav 0 4096 \n", argv[0]);
-    return err;
-  }
-
-#ifdef HAVE_WAVREAD
-  uint_t samplerate = 0;
-  uint_t hop_size = 256;
-  uint_t n_frames = 0, read = 0;
-  if ( argc >= 3 ) samplerate = atoi(argv[2]);
-  if ( argc >= 4 ) hop_size = atoi(argv[3]);
-
-  char_t *source_path = argv[1];
-
-
-  aubio_source_wavread_t * s =
-    new_aubio_source_wavread(source_path, samplerate, hop_size);
-  if (!s) { err = 1; goto beach; }
-  fvec_t *vec = new_fvec(hop_size);
-
-  uint_t n_frames_expected = aubio_source_wavread_get_duration(s);
-
-  samplerate = aubio_source_wavread_get_samplerate(s);
-
-  do {
-    aubio_source_wavread_do(s, vec, &read);
-    fvec_print (vec);
-    n_frames += read;
-  } while ( read == hop_size );
-
-  PRINT_MSG("read %d frames (expected %d) at %dHz (%d blocks) from %s\n",
-            n_frames, n_frames_expected, samplerate, n_frames / hop_size,
-            source_path);
-
-  del_fvec (vec);
-  del_aubio_source_wavread (s);
-beach:
-#else
-  err = 0;
-  PRINT_ERR("aubio was not compiled with aubio_source_wavread\n");
-#endif /* HAVE_WAVREAD */
-  return err;
+  return base_main(argc, argv);
 }
