audio: drop swapped-endian audio formats

Until now, the audio chain could handle both little endian and big
endian formats. This actually doesn't make much sense, since the audio
API and the HW will most likely prefer native formats. Or at the very
least, it should be trivial for audio drivers to do the byte swapping
themselves.

From now on, the audio chain contains native-endian formats only. All
AOs and some filters are adjusted. af_convertsignendian.c is now wrongly
named, but the filter name is adjusted. In some cases, the audio
infrastructure was reused on the demuxer side, but that is relatively
easy to rectify.

This is a quite intrusive and radical change. It's possible that it will
break some things (especially if they're obscure or not Linux), so watch
out for regressions. It's probably still better to do it the bulldozer
way, since slow transition and researching foreign platforms would take
a lot of time and effort.

1 files changed, 9 insertions, 41 deletions

diff --git a/audio/filter/af_convertsignendian.c b/audio/filter/af_convertsignendian.c
index a0b47b38a3..7e7e436352 100644
--- a/audio/filter/af_convertsignendian.c
+++ b/audio/filter/af_convertsignendian.c
@@ -20,21 +20,16 @@
 
 #include "af.h"
 #include "audio/format.h"
-#include "osdep/mpbswap.h"
+#include "osdep/endian.h"
 
 static bool test_conversion(int src_format, int dst_format)
 {
     if ((src_format & AF_FORMAT_PLANAR) ||
         (dst_format & AF_FORMAT_PLANAR))
         return false;
-    int src_noend = src_format & ~AF_FORMAT_END_MASK;
-    int dst_noend = dst_format & ~AF_FORMAT_END_MASK;
-    // We can swap endian for all formats, but sign only for integer formats.
-    if (src_noend == dst_noend)
-        return true;
-    if (((src_noend & ~AF_FORMAT_SIGN_MASK) ==
-         (dst_noend & ~AF_FORMAT_SIGN_MASK)) &&
-        ((src_noend & AF_FORMAT_POINT_MASK) == AF_FORMAT_I))
+    if (((src_format & ~AF_FORMAT_SIGN_MASK) ==
+         (dst_format & ~AF_FORMAT_SIGN_MASK)) &&
+        ((src_format & AF_FORMAT_POINT_MASK) == AF_FORMAT_I))
         return true;
     return false;
 }
@@ -63,34 +58,11 @@ static int control(struct af_instance *af, int cmd, void *arg)
     return AF_UNKNOWN;
 }
 
-static void endian(void *data, int len, int bps)
-{
-    switch (bps) {
-    case 2:
-        for (int i = 0; i < len; i++) {
-            ((uint16_t*)data)[i] = bswap_16(((uint16_t *)data)[i]);
-        }
-        break;
-    case 3:
-        for(int i = 0; i < len; i++) {
-            uint8_t s = ((uint8_t *)data)[3 * i];
-            ((uint8_t *)data)[3 * i] = ((uint8_t *)data)[3 * i + 2];
-            ((uint8_t *)data)[3 * i + 2] = s;
-        }
-        break;
-    case 4:
-        for(int i = 0; i < len; i++) {
-            ((uint32_t*)data)[i] = bswap_32(((uint32_t *)data)[i]);
-        }
-        break;
-    }
-}
-
-static void si2us(void *data, int len, int bps, bool le)
+static void si2us(void *data, int len, int bps)
 {
     ptrdiff_t i = -(len * bps);
     uint8_t *p = &((uint8_t *)data)[len * bps];
-    if (le && bps > 1)
+    if (BYTE_ORDER == LITTLE_ENDIAN && bps > 1)
         p += bps - 1;
     if (len <= 0)
         return;
@@ -105,12 +77,8 @@ static int filter(struct af_instance *af, struct mp_audio *data, int flags)
     int outfmt = af->data->format;
     size_t len = data->samples * data->nch;
 
-    if ((infmt & AF_FORMAT_END_MASK) != (outfmt & AF_FORMAT_END_MASK))
-        endian(data->planes[0], len, data->bps);
-
     if ((infmt & AF_FORMAT_SIGN_MASK) != (outfmt & AF_FORMAT_SIGN_MASK))
-        si2us(data->planes[0], len, data->bps,
-              (outfmt & AF_FORMAT_END_MASK) == AF_FORMAT_LE);
+        si2us(data->planes[0], len, data->bps);
 
     mp_audio_set_format(data, outfmt);
     return 0;
@@ -124,8 +92,8 @@ static int af_open(struct af_instance *af)
 }
 
 const struct af_info af_info_convertsignendian = {
-    .info = "Convert between sample format sign/endian",
-    .name = "convertsignendian",
+    .info = "Convert between sample format sign",
+    .name = "convertsign",
     .open = af_open,
     .test_conversion = test_conversion,
 };