Remove AudioCVT interface in favor of SDL_AudioStream

include/SDL3/SDL_audio.h

@@ -191,59 +191,6 @@ typedef struct SDL_AudioSpec
 } SDL_AudioSpec;
 
 
-struct SDL_AudioCVT;
-typedef void (SDLCALL * SDL_AudioFilter) (struct SDL_AudioCVT * cvt,
-                                          SDL_AudioFormat format);
-
-/**
- *  \brief Upper limit of filters in SDL_AudioCVT
- *
- *  The maximum number of SDL_AudioFilter functions in SDL_AudioCVT is
- *  currently limited to 9. The SDL_AudioCVT.filters array has 10 pointers,
- *  one of which is the terminating NULL pointer.
- */
-#define SDL_AUDIOCVT_MAX_FILTERS 9
-
-/**
- *  \struct SDL_AudioCVT
- *  \brief A structure to hold a set of audio conversion filters and buffers.
- *
- *  Note that various parts of the conversion pipeline can take advantage
- *  of SIMD operations (like SSE2, for example). SDL_AudioCVT doesn't require
- *  you to pass it aligned data, but can possibly run much faster if you
- *  set both its (buf) field to a pointer that is aligned to 16 bytes, and its
- *  (len) field to something that's a multiple of 16, if possible.
- */
-#if defined(__GNUC__) && !defined(__CHERI_PURE_CAPABILITY__)
-/* This structure is 84 bytes on 32-bit architectures, make sure GCC doesn't
-   pad it out to 88 bytes to guarantee ABI compatibility between compilers.
-   This is not a concern on CHERI architectures, where pointers must be stored
-   at aligned locations otherwise they will become invalid, and thus structs
-   containing pointers cannot be packed without giving a warning or error.
-   vvv
-   The next time we rev the ABI, make sure to size the ints and add padding.
-*/
-#define SDL_AUDIOCVT_PACKED __attribute__((packed))
-#else
-#define SDL_AUDIOCVT_PACKED
-#endif
-/* */
-typedef struct SDL_AudioCVT
-{
-    int needed;                 /**< Set to 1 if conversion possible */
-    SDL_AudioFormat src_format; /**< Source audio format */
-    SDL_AudioFormat dst_format; /**< Target audio format */
-    double rate_incr;           /**< Rate conversion increment */
-    Uint8 *buf;                 /**< Buffer to hold entire audio data */
-    int len;                    /**< Length of original audio buffer */
-    int len_cvt;                /**< Length of converted audio buffer */
-    int len_mult;               /**< buffer must be len*len_mult big */
-    double len_ratio;           /**< Given len, final size is len*len_ratio */
-    SDL_AudioFilter filters[SDL_AUDIOCVT_MAX_FILTERS + 1]; /**< NULL-terminated list of filter functions */
-    int filter_index;           /**< Current audio conversion function */
-} SDL_AUDIOCVT_PACKED SDL_AudioCVT;
-
-
 /* Function prototypes */
 
 /**
@@ -734,85 +681,6 @@ extern DECLSPEC SDL_AudioSpec *SDLCALL SDL_LoadWAV_RW(SDL_RWops * src,
 #define SDL_LoadWAV(file, spec, audio_buf, audio_len) \
     SDL_LoadWAV_RW(SDL_RWFromFile(file, "rb"),1, spec,audio_buf,audio_len)
 
-/**
- * Initialize an SDL_AudioCVT structure for conversion.
- *
- * Before an SDL_AudioCVT structure can be used to convert audio data it must
- * be initialized with source and destination information.
- *
- * This function will zero out every field of the SDL_AudioCVT, so it must be
- * called before the application fills in the final buffer information.
- *
- * Once this function has returned successfully, and reported that a
- * conversion is necessary, the application fills in the rest of the fields in
- * SDL_AudioCVT, now that it knows how large a buffer it needs to allocate,
- * and then can call SDL_ConvertAudio() to complete the conversion.
- *
- * \param cvt an SDL_AudioCVT structure filled in with audio conversion
- *            information
- * \param src_format the source format of the audio data; for more info see
- *                   SDL_AudioFormat
- * \param src_channels the number of channels in the source
- * \param src_rate the frequency (sample-frames-per-second) of the source
- * \param dst_format the destination format of the audio data; for more info
- *                   see SDL_AudioFormat
- * \param dst_channels the number of channels in the destination
- * \param dst_rate the frequency (sample-frames-per-second) of the destination
- * \returns 1 if the audio filter is prepared, 0 if no conversion is needed,
- *          or a negative error code on failure; call SDL_GetError() for more
- *          information.
- *
- * \since This function is available since SDL 3.0.0.
- *
- * \sa SDL_ConvertAudio
- */
-extern DECLSPEC int SDLCALL SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
-                                              SDL_AudioFormat src_format,
-                                              Uint8 src_channels,
-                                              int src_rate,
-                                              SDL_AudioFormat dst_format,
-                                              Uint8 dst_channels,
-                                              int dst_rate);
-
-/**
- * Convert audio data to a desired audio format.
- *
- * This function does the actual audio data conversion, after the application
- * has called SDL_BuildAudioCVT() to prepare the conversion information and
- * then filled in the buffer details.
- *
- * Once the application has initialized the `cvt` structure using
- * SDL_BuildAudioCVT(), allocated an audio buffer and filled it with audio
- * data in the source format, this function will convert the buffer, in-place,
- * to the desired format.
- *
- * The data conversion may go through several passes; any given pass may
- * possibly temporarily increase the size of the data. For example, SDL might
- * expand 16-bit data to 32 bits before resampling to a lower frequency,
- * shrinking the data size after having grown it briefly. Since the supplied
- * buffer will be both the source and destination, converting as necessary
- * in-place, the application must allocate a buffer that will fully contain
- * the data during its largest conversion pass. After SDL_BuildAudioCVT()
- * returns, the application should set the `cvt->len` field to the size, in
- * bytes, of the source data, and allocate a buffer that is `cvt->len *
- * cvt->len_mult` bytes long for the `buf` field.
- *
- * The source data should be copied into this buffer before the call to
- * SDL_ConvertAudio(). Upon successful return, this buffer will contain the
- * converted audio, and `cvt->len_cvt` will be the size of the converted data,
- * in bytes. Any bytes in the buffer past `cvt->len_cvt` are undefined once
- * this function returns.
- *
- * \param cvt an SDL_AudioCVT structure that was previously set up by
- *            SDL_BuildAudioCVT().
- * \returns 0 if the conversion was completed successfully or a negative error
- *          code on failure; call SDL_GetError() for more information.
- *
- * \since This function is available since SDL 3.0.0.
- *
- * \sa SDL_BuildAudioCVT
- */
-extern DECLSPEC int SDLCALL SDL_ConvertAudio(SDL_AudioCVT * cvt);
 
 /* SDL_AudioStream is a new audio conversion interface.
    The benefits vs SDL_AudioCVT:

src/audio/SDL_audio_c.h

@@ -59,6 +59,9 @@ extern void SDL_CalculateAudioSpec(SDL_AudioSpec *spec);
 /* Choose the audio filter functions below */
 extern void SDL_ChooseAudioConverters(void);
 
+struct SDL_AudioCVT;
+typedef void (SDLCALL * SDL_AudioFilter) (struct SDL_AudioCVT * cvt, SDL_AudioFormat format);
+
 /* These pointers get set during SDL_ChooseAudioConverters() to various SIMD implementations. */
 extern SDL_AudioFilter SDL_Convert_S8_to_F32;
 extern SDL_AudioFilter SDL_Convert_U8_to_F32;

src/audio/SDL_audiocvt.c

@@ -23,6 +23,7 @@
 /* Functions for audio drivers to perform runtime conversion of audio format */
 
 #include "SDL_audio_c.h"
+#include "SDL_audiocvt_c.h"
 
 #include "../SDL_dataqueue.h"
 
@@ -56,6 +57,89 @@
 #endif
 #endif
 
+
+/**
+ * Initialize an SDL_AudioCVT structure for conversion.
+ *
+ * Before an SDL_AudioCVT structure can be used to convert audio data it must
+ * be initialized with source and destination information.
+ *
+ * This function will zero out every field of the SDL_AudioCVT, so it must be
+ * called before the application fills in the final buffer information.
+ *
+ * Once this function has returned successfully, and reported that a
+ * conversion is necessary, the application fills in the rest of the fields in
+ * SDL_AudioCVT, now that it knows how large a buffer it needs to allocate,
+ * and then can call SDL_ConvertAudio() to complete the conversion.
+ *
+ * \param cvt an SDL_AudioCVT structure filled in with audio conversion
+ *            information
+ * \param src_format the source format of the audio data; for more info see
+ *                   SDL_AudioFormat
+ * \param src_channels the number of channels in the source
+ * \param src_rate the frequency (sample-frames-per-second) of the source
+ * \param dst_format the destination format of the audio data; for more info
+ *                   see SDL_AudioFormat
+ * \param dst_channels the number of channels in the destination
+ * \param dst_rate the frequency (sample-frames-per-second) of the destination
+ * \returns 1 if the audio filter is prepared, 0 if no conversion is needed,
+ *          or a negative error code on failure; call SDL_GetError() for more
+ *          information.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_ConvertAudio
+ */
+static int SDL_BuildAudioCVT(SDL_AudioCVT * cvt,
+                             SDL_AudioFormat src_format,
+                             Uint8 src_channels,
+                             int src_rate,
+                             SDL_AudioFormat dst_format,
+                             Uint8 dst_channels,
+                             int dst_rate);
+
+
+/**
+ * Convert audio data to a desired audio format.
+ *
+ * This function does the actual audio data conversion, after the application
+ * has called SDL_BuildAudioCVT() to prepare the conversion information and
+ * then filled in the buffer details.
+ *
+ * Once the application has initialized the `cvt` structure using
+ * SDL_BuildAudioCVT(), allocated an audio buffer and filled it with audio
+ * data in the source format, this function will convert the buffer, in-place,
+ * to the desired format.
+ *
+ * The data conversion may go through several passes; any given pass may
+ * possibly temporarily increase the size of the data. For example, SDL might
+ * expand 16-bit data to 32 bits before resampling to a lower frequency,
+ * shrinking the data size after having grown it briefly. Since the supplied
+ * buffer will be both the source and destination, converting as necessary
+ * in-place, the application must allocate a buffer that will fully contain
+ * the data during its largest conversion pass. After SDL_BuildAudioCVT()
+ * returns, the application should set the `cvt->len` field to the size, in
+ * bytes, of the source data, and allocate a buffer that is `cvt->len *
+ * cvt->len_mult` bytes long for the `buf` field.
+ *
+ * The source data should be copied into this buffer before the call to
+ * SDL_ConvertAudio(). Upon successful return, this buffer will contain the
+ * converted audio, and `cvt->len_cvt` will be the size of the converted data,
+ * in bytes. Any bytes in the buffer past `cvt->len_cvt` are undefined once
+ * this function returns.
+ *
+ * \param cvt an SDL_AudioCVT structure that was previously set up by
+ *            SDL_BuildAudioCVT().
+ * \returns 0 if the conversion was completed successfully or a negative error
+ *          code on failure; call SDL_GetError() for more information.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_BuildAudioCVT
+ */
+static int SDL_ConvertAudio(SDL_AudioCVT * cvt);
+
+
 /*
  * CHANNEL LAYOUTS AS SDL EXPECTS THEM:
  *
@@ -250,7 +334,7 @@ static int SDL_ResampleAudio(const int chans, const int inrate, const int outrat
     return outframes * chans * sizeof(float);
 }
 
-int SDL_ConvertAudio(SDL_AudioCVT *cvt)
+static int SDL_ConvertAudio(SDL_AudioCVT *cvt)
 {
     /* !!! FIXME: (cvt) should be const; stack-copy it here. */
     /* !!! FIXME: (actually, we can't...len_cvt needs to be updated. Grr.) */
@@ -670,9 +754,9 @@ static SDL_bool SDL_IsSupportedChannelCount(const int channels)
    or -1 if an error like invalid parameter, unsupported format, etc. occurred.
 */
 
-int SDL_BuildAudioCVT(SDL_AudioCVT *cvt,
-                      SDL_AudioFormat src_format, Uint8 src_channels, int src_rate,
-                      SDL_AudioFormat dst_format, Uint8 dst_channels, int dst_rate)
+static int SDL_BuildAudioCVT(SDL_AudioCVT *cvt,
+                            SDL_AudioFormat src_format, Uint8 src_channels, int src_rate,
+                            SDL_AudioFormat dst_format, Uint8 dst_channels, int dst_rate)
 {
     SDL_AudioFilter channel_converter = NULL;
 

src/audio/SDL_audiocvt_c.h

@@ -0,0 +1,69 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/**
+ *  \brief Upper limit of filters in SDL_AudioCVT
+ *
+ *  The maximum number of SDL_AudioFilter functions in SDL_AudioCVT is
+ *  currently limited to 9. The SDL_AudioCVT.filters array has 10 pointers,
+ *  one of which is the terminating NULL pointer.
+ */
+#define SDL_AUDIOCVT_MAX_FILTERS 9
+
+/**
+ *  \struct SDL_AudioCVT
+ *  \brief A structure to hold a set of audio conversion filters and buffers.
+ *
+ *  Note that various parts of the conversion pipeline can take advantage
+ *  of SIMD operations (like SSE2, for example). SDL_AudioCVT doesn't require
+ *  you to pass it aligned data, but can possibly run much faster if you
+ *  set both its (buf) field to a pointer that is aligned to 16 bytes, and its
+ *  (len) field to something that's a multiple of 16, if possible.
+ */
+#if defined(__GNUC__) && !defined(__CHERI_PURE_CAPABILITY__)
+/* This structure is 84 bytes on 32-bit architectures, make sure GCC doesn't
+   pad it out to 88 bytes to guarantee ABI compatibility between compilers.
+   This is not a concern on CHERI architectures, where pointers must be stored
+   at aligned locations otherwise they will become invalid, and thus structs
+   containing pointers cannot be packed without giving a warning or error.
+   vvv
+   The next time we rev the ABI, make sure to size the ints and add padding.
+*/
+#define SDL_AUDIOCVT_PACKED __attribute__((packed))
+#else
+#define SDL_AUDIOCVT_PACKED
+#endif
+/* */
+typedef struct SDL_AudioCVT
+{
+    int needed;                 /**< Set to 1 if conversion possible */
+    SDL_AudioFormat src_format; /**< Source audio format */
+    SDL_AudioFormat dst_format; /**< Target audio format */
+    double rate_incr;           /**< Rate conversion increment */
+    Uint8 *buf;                 /**< Buffer to hold entire audio data */
+    int len;                    /**< Length of original audio buffer */
+    int len_cvt;                /**< Length of converted audio buffer */
+    int len_mult;               /**< buffer must be len*len_mult big */
+    double len_ratio;           /**< Given len, final size is len*len_ratio */
+    SDL_AudioFilter filters[SDL_AUDIOCVT_MAX_FILTERS + 1]; /**< NULL-terminated list of filter functions */
+    int filter_index;           /**< Current audio conversion function */
+} SDL_AUDIOCVT_PACKED SDL_AudioCVT;
+

src/audio/SDL_audiotypecvt.c

@@ -21,6 +21,7 @@
 #include "SDL_internal.h"
 
 #include "SDL_audio_c.h"
+#include "SDL_audiocvt_c.h"
 
 #ifdef __ARM_NEON
 #define HAVE_NEON_INTRINSICS 1

src/dynapi/SDL_dynapi.sym

@@ -32,7 +32,6 @@ SDL3_0.0.0 {
     SDL_BlitSurfaceScaled;
     SDL_BlitSurfaceUnchecked;
     SDL_BlitSurfaceUncheckedScaled;
-    SDL_BuildAudioCVT;
     SDL_CaptureMouse;
     SDL_ClearAudioStream;
     SDL_ClearComposition;
@@ -48,7 +47,6 @@ SDL3_0.0.0 {
     SDL_CondSignal;
     SDL_CondWait;
     SDL_CondWaitTimeout;
-    SDL_ConvertAudio;
     SDL_ConvertPixels;
     SDL_ConvertSurface;
     SDL_ConvertSurfaceFormat;

src/dynapi/SDL_dynapi_overrides.h

@@ -57,7 +57,6 @@
 #define SDL_BlitSurfaceScaled SDL_BlitSurfaceScaled_REAL
 #define SDL_BlitSurfaceUnchecked SDL_BlitSurfaceUnchecked_REAL
 #define SDL_BlitSurfaceUncheckedScaled SDL_BlitSurfaceUncheckedScaled_REAL
-#define SDL_BuildAudioCVT SDL_BuildAudioCVT_REAL
 #define SDL_CaptureMouse SDL_CaptureMouse_REAL
 #define SDL_ClearAudioStream SDL_ClearAudioStream_REAL
 #define SDL_ClearComposition SDL_ClearComposition_REAL
@@ -73,7 +72,6 @@
 #define SDL_CondSignal SDL_CondSignal_REAL
 #define SDL_CondWait SDL_CondWait_REAL
 #define SDL_CondWaitTimeout SDL_CondWaitTimeout_REAL
-#define SDL_ConvertAudio SDL_ConvertAudio_REAL
 #define SDL_ConvertPixels SDL_ConvertPixels_REAL
 #define SDL_ConvertSurface SDL_ConvertSurface_REAL
 #define SDL_ConvertSurfaceFormat SDL_ConvertSurfaceFormat_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -138,7 +138,6 @@ SDL_DYNAPI_PROC(int,SDL_BlitSurface,(SDL_Surface *a, const SDL_Rect *b, SDL_Surf
 SDL_DYNAPI_PROC(int,SDL_BlitSurfaceScaled,(SDL_Surface *a, const SDL_Rect *b, SDL_Surface *c, SDL_Rect *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_BlitSurfaceUnchecked,(SDL_Surface *a, SDL_Rect *b, SDL_Surface *c, SDL_Rect *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_BlitSurfaceUncheckedScaled,(SDL_Surface *a, SDL_Rect *b, SDL_Surface *c, SDL_Rect *d),(a,b,c,d),return)
-SDL_DYNAPI_PROC(int,SDL_BuildAudioCVT,(SDL_AudioCVT *a, SDL_AudioFormat b, Uint8 c, int d, SDL_AudioFormat e, Uint8 f, int g),(a,b,c,d,e,f,g),return)
 SDL_DYNAPI_PROC(int,SDL_CaptureMouse,(SDL_bool a),(a),return)
 SDL_DYNAPI_PROC(void,SDL_ClearAudioStream,(SDL_AudioStream *a),(a),)
 SDL_DYNAPI_PROC(void,SDL_ClearComposition,(void),(),)
@@ -154,7 +153,6 @@ SDL_DYNAPI_PROC(int,SDL_CondBroadcast,(SDL_cond *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_CondSignal,(SDL_cond *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_CondWait,(SDL_cond *a, SDL_mutex *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_CondWaitTimeout,(SDL_cond *a, SDL_mutex *b, Sint32 c),(a,b,c),return)
-SDL_DYNAPI_PROC(int,SDL_ConvertAudio,(SDL_AudioCVT *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_ConvertPixels,(int a, int b, Uint32 c, const void *d, int e, Uint32 f, void *g, int h),(a,b,c,d,e,f,g,h),return)
 SDL_DYNAPI_PROC(SDL_Surface*,SDL_ConvertSurface,(SDL_Surface *a, const SDL_PixelFormat *b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_Surface*,SDL_ConvertSurfaceFormat,(SDL_Surface *a, Uint32 b),(a,b),return)