Add --enable-abicheck configure option

19 files changed, 141 insertions, 0 deletions

diff --git a/README b/README
index c6a54e7..39b7233 100644
--- a/README
+++ b/README
@@ -102,6 +102,9 @@ It's disabled as default.
 With option --enable-libasound, libasound.so will be created as an
 opt-in ABI-compatible library with the genuine ALSA-lib.
 
+When --enable-abicheck is given, each open function checks the ABI
+compatibility with the installed library.
+
 All these options can be enabled via a single option,
 --enable-everything, for your convenience.
 
diff --git a/configure.ac b/configure.ac
index 2227ed9..70c552b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -121,6 +121,11 @@ AC_ARG_ENABLE(float,
 		 [drop the support for 4bit PCM (IMA ADPCM)]),
   support_4bit="$enableval", support_4bit="yes")
 
+AC_ARG_ENABLE(abicheck,
+  AS_HELP_STRING([--enable-abicheck],
+		 [enable library ABI check]),
+  abicheck="$enableval", abicheck="no")
+
 AC_ARG_ENABLE(everything,
   AS_HELP_STRING([--enable-everything],
 		 [enable everything :)]),
@@ -141,6 +146,7 @@ if test "$everything" = "yes"; then
   output_buffer="yes"
   support_float="yes"
   support_4bit="yes"
+  abicheck="yes"
 fi
 
 SALSA_DEPLIBS=""
@@ -183,6 +189,7 @@ else
   SALSA_MARK_DEPRECATED=0
 fi
 AC_SUBST(SALSA_MARK_DEPRECATED)
+
 if test "$output_buffer" = "yes"; then
   SALSA_SUPPORT_OUTPUT_BUFFER=1
 else
@@ -205,6 +212,13 @@ else
 fi
 AC_SUBST(SALSA_SUPPORT_4BIT_PCM)
 
+if test "$abicheck" = "yes"; then
+  SALSA_CHECK_ABI=1
+else
+  SALSA_CHECK_ABI=0
+fi
+AC_SUBST(SALSA_CHECK_ABI)
+
 if test "$delight_valgrind" = "yes"; then
   AC_DEFINE(DELIGHT_VALGRIND)
 fi
@@ -261,3 +275,4 @@ echo "  - Make ABI-compatible libasound.so: $libasound"
 echo "  - Mark deprecated attribute: $markdeprecated"
 echo "  - Support string-output via snd_output: $output_buffer"
 echo "  - Support floating-point: $support_float"
+echo "  - Enable library ABI check: $abicheck"
diff --git a/src/control.c b/src/control.c
index 522f986..ff47a74 100644
--- a/src/control.c
+++ b/src/control.c
@@ -38,12 +38,19 @@
  * open/close
  */
 
+#if SALSA_CHECK_ABI
+int _snd_ctl_open(snd_ctl_t **ctlp, const char *name, int mode,
+		  unsigned int magic)
+#else
 int snd_ctl_open(snd_ctl_t **ctlp, const char *name, int mode)
+#endif
 {
 	snd_ctl_t *ctl;
 	char filename[sizeof(SALSA_DEVPATH) + 24];
 	int err, fmode, fd, card, ver;
 
+	check_incompatible_abi(magic, SALSA_CTL_MAGIC);
+
 	*ctlp = NULL;
 
 	err = _snd_dev_get_device(name, &card, NULL, NULL);
diff --git a/src/ctl_func.h b/src/ctl_func.h
index 87ff259..32de1c6 100644
--- a/src/ctl_func.h
+++ b/src/ctl_func.h
@@ -27,7 +27,12 @@ int snd_card_get_index(const char *name);
 int snd_card_get_name(int card, char **name);
 int snd_card_get_longname(int card, char **name);
 
+#if SALSA_CHECK_ABI
+int _snd_ctl_open(snd_ctl_t **ctl, const char *name, int mode,
+		  unsigned int magic);
+#else
 int snd_ctl_open(snd_ctl_t **ctl, const char *name, int mode);
+#endif
 int snd_ctl_close(snd_ctl_t *ctl);
 int snd_ctl_wait(snd_ctl_t *ctl, int timeout);
 
diff --git a/src/ctl_macros.h b/src/ctl_macros.h
index fae15c0..d690942 100644
--- a/src/ctl_macros.h
+++ b/src/ctl_macros.h
@@ -28,6 +28,15 @@ struct _snd_ctl {
 };
 
 
+#if SALSA_CHECK_ABI
+#define SALSA_CTL_MAGIC		sizeof(struct _snd_ctl)
+__SALSA_EXPORT_FUNC
+int snd_ctl_open(snd_ctl_t **ctl, const char *name, int mode)
+{
+	return _snd_ctl_open(ctl, name, mode, SALSA_CTL_MAGIC);
+}
+#endif
+
 __SALSA_EXPORT_FUNC
 int snd_ctl_nonblock(snd_ctl_t *ctl, int nonblock)
 {
diff --git a/src/hcontrol.c b/src/hcontrol.c
index 22a862b..86d4aed 100644
--- a/src/hcontrol.c
+++ b/src/hcontrol.c
@@ -34,11 +34,18 @@
 /*
  * open/close
  */
+#if SALSA_CHECK_ABI
+int _snd_hctl_open(snd_hctl_t **hctlp, const char *name, int mode,
+		   unsigned int magic)
+#else
 int snd_hctl_open(snd_hctl_t **hctlp, const char *name, int mode)
+#endif
 {
 	snd_ctl_t *ctl;
 	int err;
 	
+	check_incompatible_abi(magic, SALSA_HCTL_MAGIC);
+
 	err = snd_ctl_open(&ctl, name, mode);
 	if (err < 0)
 		return err;
diff --git a/src/hctl_func.h b/src/hctl_func.h
index 5d925d0..678b548 100644
--- a/src/hctl_func.h
+++ b/src/hctl_func.h
@@ -18,7 +18,12 @@ typedef int (*snd_hctl_callback_t)(snd_hctl_t *hctl,
 typedef int (*snd_hctl_elem_callback_t)(snd_hctl_elem_t *elem,
 					unsigned int mask);
 
+#if SALSA_CHECK_ABI
+int _snd_hctl_open(snd_hctl_t **hctl, const char *name, int mode,
+		   unsigned int magic);
+#else
 int snd_hctl_open(snd_hctl_t **hctl, const char *name, int mode);
+#endif
 int snd_hctl_open_ctl(snd_hctl_t **hctlp, snd_ctl_t *ctl);
 int snd_hctl_close(snd_hctl_t *hctl);
 snd_hctl_elem_t *snd_hctl_find_elem(snd_hctl_t *hctl, const snd_ctl_elem_id_t *id);
diff --git a/src/hctl_macros.h b/src/hctl_macros.h
index 8ebe476..fc1348b 100644
--- a/src/hctl_macros.h
+++ b/src/hctl_macros.h
@@ -34,6 +34,16 @@ struct _snd_hctl_elem {
 };
 
 
+#if SALSA_CHECK_ABI
+#define SALSA_HCTL_MAGIC \
+	((sizeof(struct _snd_hctl) << 8) | sizeof(struct _snd_hctl_elem))
+__SALSA_EXPORT_FUNC
+int snd_hctl_open(snd_hctl_t **hctl, const char *name, int mode)
+{
+	return _snd_hctl_open(hctl, name, mode, SALSA_HCTL_MAGIC);
+}
+#endif
+
 __SALSA_EXPORT_FUNC
 int snd_hctl_wait(snd_hctl_t *hctl, int timeout)
 {
diff --git a/src/local.h b/src/local.h
index 64ea15a..05e09da 100644
--- a/src/local.h
+++ b/src/local.h
@@ -17,4 +17,11 @@ int _snd_pcm_munmap(snd_pcm_t *pcm);
 #define memzero_valgrind(buf, size)
 #endif
 
+#if SALSA_CHECK_ABI
+#include <assert.h>
+#define check_incompatible_abi(magic, orig) assert(magic == orig)
+#else
+#define check_incompatible_abi(magic, orig)
+#endif
+
 #endif /* __LOCAL_H_INC */
diff --git a/src/mixer.c b/src/mixer.c
index 11ac673..3f87eca 100644
--- a/src/mixer.c
+++ b/src/mixer.c
@@ -33,9 +33,16 @@
 static int hctl_event_handler(snd_hctl_t *hctl, unsigned int mask,
 			      snd_hctl_elem_t *elem);
 
+#if SALSA_CHECK_ABI
+int _snd_mixer_open(snd_mixer_t **mixerp, int mode, unsigned int magic)
+#else
 int snd_mixer_open(snd_mixer_t **mixerp, int mode)
+#endif
 {
 	snd_mixer_t *mixer;
+
+	check_incompatible_abi(magic, SALSA_MIXER_MAGIC);
+
 	mixer = calloc(1, sizeof(*mixer));
 	*mixerp = mixer;
 	if (mixer == NULL)
diff --git a/src/mixer_func.h b/src/mixer_func.h
index 841c5fa..3eb0174 100644
--- a/src/mixer_func.h
+++ b/src/mixer_func.h
@@ -56,7 +56,11 @@ struct snd_mixer_selem_regopt {
 
 typedef struct _snd_mixer_selem_id snd_mixer_selem_id_t;
 
+#if SALSA_CHECK_ABI
+int _snd_mixer_open(snd_mixer_t **mixer, int mode, unsigned int magic);
+#else
 int snd_mixer_open(snd_mixer_t **mixer, int mode);
+#endif
 int snd_mixer_close(snd_mixer_t *mixer);
 int snd_mixer_handle_events(snd_mixer_t *mixer);
 int snd_mixer_attach(snd_mixer_t *mixer, const char *name);
diff --git a/src/mixer_macros.h b/src/mixer_macros.h
index c1372bf..8c8ae86 100644
--- a/src/mixer_macros.h
+++ b/src/mixer_macros.h
@@ -89,6 +89,18 @@ struct _snd_mixer_elem {
 };
 
 
+#if SALSA_CHECK_ABI
+#define SALSA_MIXER_MAGIC \
+	(sizeof(struct _snd_mixer) | (sizeof(struct _snd_mixer_elem) << 8) | \
+	 (sizeof(snd_selem_item_head_t) + sizeof(snd_selem_vol_item_t) + \
+	  sizeof(snd_selem_sw_item_t) + sizeof(snd_selem_enum_item_t)))
+__SALSA_EXPORT_FUNC
+int snd_mixer_open(snd_mixer_t **mixer, int mode)
+{
+	return _snd_mixer_open(mixer, mode, SALSA_MIXER_MAGIC);
+}
+#endif
+
 __SALSA_EXPORT_FUNC
 int snd_mixer_poll_descriptors_count(snd_mixer_t *mixer)
 {
diff --git a/src/pcm.c b/src/pcm.c
index 38313a6..27db757 100644
--- a/src/pcm.c
+++ b/src/pcm.c
@@ -49,14 +49,21 @@ static int get_pcm_subdev(int fd)
 	return info.subdevice;
 }
 
+#if SALSA_CHECK_ABI
+int _snd_pcm_open(snd_pcm_t **pcmp, const char *name, 
+		  snd_pcm_stream_t stream, int mode, unsigned int magic)
+#else
 int snd_pcm_open(snd_pcm_t **pcmp, const char *name, 
 		 snd_pcm_stream_t stream, int mode)
+#endif
 {
 	char filename[sizeof(SALSA_DEVPATH) + 24];
 	int card, dev, subdev;
 	int fd, err, fmode, ver;
 	snd_pcm_t *pcm = NULL;
 
+	check_incompatible_abi(magic, SALSA_PCM_MAGIC);
+
 	*pcmp = NULL;
 
 	err = _snd_dev_get_device(name, &card, &dev, &subdev);
diff --git a/src/pcm_func.h b/src/pcm_func.h
index 7cea5f5..d1c6b42 100644
--- a/src/pcm_func.h
+++ b/src/pcm_func.h
@@ -77,8 +77,13 @@ typedef struct _snd_pcm_channel_area {
 	unsigned int step;
 } snd_pcm_channel_area_t;
 
+#if SALSA_CHECK_ABI
+int _snd_pcm_open(snd_pcm_t **pcm, const char *name, 
+		  snd_pcm_stream_t stream, int mode, unsigned int magic);
+#else
 int snd_pcm_open(snd_pcm_t **pcm, const char *name, 
 		 snd_pcm_stream_t stream, int mode);
+#endif
 int snd_pcm_close(snd_pcm_t *pcm);
 int snd_pcm_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);
 int snd_pcm_hw_free(snd_pcm_t *pcm);
diff --git a/src/pcm_macros.h b/src/pcm_macros.h
index 91daab6..85ff656 100644
--- a/src/pcm_macros.h
+++ b/src/pcm_macros.h
@@ -74,6 +74,16 @@ struct _snd_pcm {
  * Macros
  */
 
+#if SALSA_CHECK_ABI
+#define SALSA_PCM_MAGIC		sizeof(struct _snd_pcm)
+__SALSA_EXPORT_FUNC
+int snd_pcm_open(snd_pcm_t **pcm, const char *name, 
+		 snd_pcm_stream_t stream, int mode)
+{
+	return _snd_pcm_open(pcm, name, stream, mode, SALSA_PCM_MAGIC);
+}
+#endif
+
 __SALSA_EXPORT_FUNC
 int snd_pcm_nonblock(snd_pcm_t *pcm, int nonblock)
 {
diff --git a/src/rawmidi.c b/src/rawmidi.c
index e30ddf5..46332ac 100644
--- a/src/rawmidi.c
+++ b/src/rawmidi.c
@@ -66,14 +66,21 @@ static snd_rawmidi_t *new_rmidi(snd_rawmidi_hw_t *hw, int stream, int mode)
 	return rmidi;
 }
 
+#if SALSA_CHECK_ABI
+int _snd_rawmidi_open(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
+		      const char *name, int mode, unsigned int magic)
+#else
 int snd_rawmidi_open(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
 		     const char *name, int mode)
+#endif
 {
 	int fd, err, fmode, ver;
 	int card, dev, subdev;
 	char filename[sizeof(SALSA_DEVPATH) + 24];
 	snd_rawmidi_hw_t *hw;
 
+	check_incompatible_abi(magic, SALSA_RAWMIDI_MAGIC);
+
 	if (in_rmidi)
 		*in_rmidi = NULL;
 	if (out_rmidi)
diff --git a/src/rawmidi_func.h b/src/rawmidi_func.h
index c6c49fd..e108e93 100644
--- a/src/rawmidi_func.h
+++ b/src/rawmidi_func.h
@@ -16,7 +16,12 @@ typedef enum _snd_rawmidi_type {
 	SND_RAWMIDI_TYPE_VIRTUAL	/* not used by SALSA */
 } snd_rawmidi_type_t;
 
+#if SALSA_CHECK_ABI
+int _snd_rawmidi_open(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
+		      const char *name, int mode, unsigned int magic);
+#else
 int snd_rawmidi_open(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
 		     const char *name, int mode);
+#endif
 int snd_rawmidi_close(snd_rawmidi_t *rmidi);
 
diff --git a/src/rawmidi_macros.h b/src/rawmidi_macros.h
index 9586c18..c32b440 100644
--- a/src/rawmidi_macros.h
+++ b/src/rawmidi_macros.h
@@ -34,6 +34,18 @@ struct _snd_rawmidi {
 /*
  */
 
+#if SALSA_CHECK_ABI
+#define SALSA_RAWMIDI_MAGIC \
+	((sizeof(struct _snd_rawmidi_hw) << 8) | sizeof(struct _snd_rawmidi))
+__SALSA_EXPORT_FUNC
+int snd_rawmidi_open(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
+		     const char *name, int mode)
+{
+	return _snd_rawmidi_open(in_rmidi, out_rmidi, name, mode,
+				 SALSA_RAWMIDI_MAGIC);
+}
+#endif
+
 __SALSA_EXPORT_FUNC __SALSA_NOT_IMPLEMENTED
 int snd_rawmidi_open_lconf(snd_rawmidi_t **in_rmidi, snd_rawmidi_t **out_rmidi,
 			   const char *name, int mode, snd_config_t *lconf)
diff --git a/src/recipe.h.in b/src/recipe.h.in
index b59b867..9a99150 100644
--- a/src/recipe.h.in
+++ b/src/recipe.h.in
@@ -22,6 +22,10 @@
 /* Support 4bit PCM (IMA ADPCM) */
 #define SALSA_SUPPORT_4BIT_PCM	@SALSA_SUPPORT_4BIT_PCM@
 
+/* Enable library ABI check */
+#define SALSA_CHECK_ABI		@SALSA_CHECK_ABI@
+
+/* Default device path prefix */
 #define SALSA_DEVPATH "@DEVPATH@"
 
 #endif /* __ALSA_RECIPE_H */