Deprecate SbMediaGetBuffer{Alignment|Padding} (#3222)

Deprecate SbMediaGetBufferAlignment() and SbMediaGetBufferPadding().

Modified nplb tests to ensure that the alignment is always set to 1 and
padding to 0.

b/322027866

Change-Id: Ic6b5eac192d505b1b22309d3bd09d5d3291a4fed

starboard/CHANGELOG.md

@@ -176,7 +176,20 @@ standard APIs `malloc`, `realloc`, `calloc`, `posix_memalign`, `free`
 from `<stdlib.h>` and `strdup` from `<string.h>` should be used instead.
 
 ### Deprecated SbMediaGetBufferAlignment
-The `SbMediaGetBufferAlignment` API was deprecated.
+The `SbMediaGetBufferAlignment` API was deprecated, its return value is no
+longer used when allocating media buffers and has to be always set to 1.  This
+is verified explicitly using nplb tests.
+The app MAY take best effort to allocate media buffers aligned to an optimal
+alignment for the platform, but not guaranteed.
+An implementation that has specific alignment requirement should check the
+alignment of the incoming buffer, and make a copy when necessary.
+
+### Deprecated SbMediaGetBufferPadding
+The SbMediaGetBufferPadding() API was deprecated, its return value is no longer
+used when allocating media buffers and has to be always set to 0.  This is
+verified explicitly using nplb tests.
+An implementation that has specific padding requirement should make a copy of
+the incoming buffer when necessary.
 
 ### Removed SbUser from SbStorageOpenRecord and SbStorageDeleteRecord
 The `SbStorageOpenRecord` and `SbStorageDeleteRecord` APIs defined in

starboard/nplb/media_buffer_test.cc

@@ -174,9 +174,21 @@ TEST(SbMediaBufferTest, Alignment) {
 #else   // SB_API_VERSION >= 14
     int alignment = SbMediaGetBufferAlignment(type);
 #endif  // SB_API_VERSION >= 14
+
+#if SB_API_VERSION >= 16
+    // SbMediaGetBufferAlignment() was deprecated in Starboard 16, its return
+    // value is no longer used when allocating media buffers.  This is verified
+    // explicitly here by ensuring its return value is 1.
+    // The app MAY take best effort to allocate media buffers aligned to an
+    // optimal alignment for the platform, but not guaranteed.
+    // An implementation that has specific alignment requirement should check
+    // the alignment of the incoming buffer, and make a copy when necessary.
+    EXPECT_EQ(alignment, 1);
+#else   // SB_API_VERSION >= 16
     EXPECT_GE(alignment, 1);
     EXPECT_EQ(alignment & (alignment - 1), 0)
         << "Alignment must always be a power of 2";
+#endif  // SB_API_VERSION >= 16
   }
 }
 #endif  // SB_API_VERSION < 16
@@ -266,13 +278,25 @@ TEST(SbMediaBufferTest, MaxCapacity) {
 }
 
 TEST(SbMediaBufferTest, Padding) {
+#if SB_API_VERSION >= 16
+  // SbMediaGetBufferPadding() was deprecated in Starboard 16, its return value
+  // is no longer used when allocating media buffers.  This is verified
+  // explicitly here by ensuring its return value is 0.
+  // An implementation that has specific padding requirement should make a
+  // copy of the incoming buffer when necessary.
+  EXPECT_EQ(SbMediaGetBufferPadding(), 0);
+
+#else  // SB_API_VERSION >= 16
+
 #if SB_API_VERSION >= 14
   EXPECT_GE(SbMediaGetBufferPadding(), 0);
 #else   // SB_API_VERSION >= 14
   for (auto type : kMediaTypes) {
     EXPECT_GE(SbMediaGetBufferPadding(type), 0);
   }
 #endif  // SB_API_VERSION >= 14
+
+#endif  // SB_API_VERSION >= 16
 }
 
 TEST(SbMediaBufferTest, PoolAllocateOnDemand) {