add new silence memblock caching subsystem

git-svn-id: file:///home/lennart/svn/public/pulseaudio/branches/glitch-free@2272 fefdeb5f-60dc-0310-8127-8f9354f1896f

2 files changed, 119 insertions, 45 deletions

diff --git a/src/pulsecore/sample-util.c b/src/pulsecore/sample-util.c
index 4a532f29..bf1f7c26 100644
--- a/src/pulsecore/sample-util.c
+++ b/src/pulsecore/sample-util.c
@@ -42,28 +42,6 @@
 
 #define PA_SILENCE_MAX (PA_PAGE_SIZE*16)
 
-pa_memblock *pa_silence_memblock_new(pa_mempool *pool, const pa_sample_spec *spec, size_t length) {
-    pa_memblock *b;
-
-    pa_assert(pool);
-    pa_assert(spec);
-
-    if (length <= 0)
-        length = PA_MIN(pa_bytes_per_second(spec)/20, /* 50 ms */
-                        pa_mempool_block_size_max(pool));
-
-    if (length > PA_SILENCE_MAX)
-        length = PA_SILENCE_MAX;
-
-    length = pa_frame_align(length, spec);
-
-    b = pa_silence_memblock(pa_memblock_new(pool, length), spec);
-
-    pa_memblock_set_is_silence(b, TRUE);
-
-    return b;
-}
-
 pa_memblock *pa_silence_memblock(pa_memblock* b, const pa_sample_spec *spec) {
     void *data;
 
@@ -77,7 +55,7 @@ pa_memblock *pa_silence_memblock(pa_memblock* b, const pa_sample_spec *spec) {
     return b;
 }
 
-void pa_silence_memchunk(pa_memchunk *c, const pa_sample_spec *spec) {
+pa_memchunk* pa_silence_memchunk(pa_memchunk *c, const pa_sample_spec *spec) {
     void *data;
 
     pa_assert(c);
@@ -87,37 +65,38 @@ void pa_silence_memchunk(pa_memchunk *c, const pa_sample_spec *spec) {
     data = pa_memblock_acquire(c->memblock);
     pa_silence_memory((uint8_t*) data+c->index, c->length, spec);
     pa_memblock_release(c->memblock);
-}
 
-void pa_silence_memory(void *p, size_t length, const pa_sample_spec *spec) {
-    uint8_t c = 0;
-    pa_assert(p);
-    pa_assert(length > 0);
-    pa_assert(spec);
+    return c;
+}
 
-    switch (spec->format) {
+static uint8_t silence_byte(pa_sample_format_t format) {
+    switch (format) {
         case PA_SAMPLE_U8:
-            c = 0x80;
-            break;
+            return 0x80;
         case PA_SAMPLE_S16LE:
         case PA_SAMPLE_S16BE:
         case PA_SAMPLE_S32LE:
         case PA_SAMPLE_S32BE:
-        case PA_SAMPLE_FLOAT32:
-        case PA_SAMPLE_FLOAT32RE:
-            c = 0;
-            break;
+        case PA_SAMPLE_FLOAT32LE:
+        case PA_SAMPLE_FLOAT32BE:
+            return 0;
         case PA_SAMPLE_ALAW:
-            c = 0xd5;
-            break;
+            return 0xd5;
         case PA_SAMPLE_ULAW:
-            c = 0xff;
-            break;
+            return 0xff;
         default:
             pa_assert_not_reached();
     }
+    return 0;
+}
 
-    memset(p, c, length);
+void* pa_silence_memory(void *p, size_t length, const pa_sample_spec *spec) {
+    pa_assert(p);
+    pa_assert(length > 0);
+    pa_assert(spec);
+
+    memset(p, silence_byte(spec->format), length);
+    return p;
 }
 
 static void calc_linear_integer_stream_volumes(pa_mix_info streams[], unsigned nstreams, const pa_sample_spec *spec) {
@@ -934,3 +913,90 @@ void pa_deinterleave(const void *src, void *dst[], unsigned channels, size_t ss,
         }
     }
 }
+
+static pa_memblock *silence_memblock_new(pa_mempool *pool, uint8_t c) {
+    pa_memblock *b;
+    size_t length;
+    void *data;
+
+    pa_assert(pool);
+
+    length = PA_MIN(pa_mempool_block_size_max(pool), PA_SILENCE_MAX);
+
+    b = pa_memblock_new(pool, length);
+
+    data = pa_memblock_acquire(b);
+    memset(data, c, length);
+    pa_memblock_release(b);
+
+    pa_memblock_set_is_silence(b, TRUE);
+
+    return b;
+}
+
+void pa_silence_cache_init(pa_silence_cache *cache) {
+    pa_assert(cache);
+
+    memset(cache, 0, sizeof(pa_silence_cache));
+}
+
+void pa_silence_cache_done(pa_silence_cache *cache) {
+    pa_sample_format_t f;
+    pa_assert(cache);
+
+    for (f = 0; f < PA_SAMPLE_MAX; f++)
+        if (cache->blocks[f])
+            pa_memblock_unref(cache->blocks[f]);
+
+    memset(cache, 0, sizeof(pa_silence_cache));
+}
+
+pa_memchunk* pa_silence_memchunk_get(pa_silence_cache *cache, pa_mempool *pool, pa_memchunk* ret, const pa_sample_spec *spec, size_t length) {
+    pa_memblock *b;
+    size_t l;
+
+    pa_assert(cache);
+    pa_assert(pa_sample_spec_valid(spec));
+
+    if (!(b = cache->blocks[spec->format]))
+
+        switch (spec->format) {
+            case PA_SAMPLE_U8:
+                cache->blocks[PA_SAMPLE_U8] = b = silence_memblock_new(pool, 0x80);
+                break;
+            case PA_SAMPLE_S16LE:
+            case PA_SAMPLE_S16BE:
+            case PA_SAMPLE_S32LE:
+            case PA_SAMPLE_S32BE:
+            case PA_SAMPLE_FLOAT32LE:
+            case PA_SAMPLE_FLOAT32BE:
+                cache->blocks[PA_SAMPLE_S16LE] = b = silence_memblock_new(pool, 0);
+                cache->blocks[PA_SAMPLE_S16BE] = pa_memblock_ref(b);
+                cache->blocks[PA_SAMPLE_S32LE] = pa_memblock_ref(b);
+                cache->blocks[PA_SAMPLE_S32BE] = pa_memblock_ref(b);
+                cache->blocks[PA_SAMPLE_FLOAT32LE] = pa_memblock_ref(b);
+                cache->blocks[PA_SAMPLE_FLOAT32BE] = pa_memblock_ref(b);
+                break;
+            case PA_SAMPLE_ALAW:
+                cache->blocks[PA_SAMPLE_ALAW] = b = silence_memblock_new(pool, 0xd5);
+                break;
+            case PA_SAMPLE_ULAW:
+                cache->blocks[PA_SAMPLE_ULAW] = b = silence_memblock_new(pool, 0xff);
+                break;
+            default:
+                pa_assert_not_reached();
+    }
+
+    pa_assert(b);
+
+    ret->memblock = pa_memblock_ref(b);
+
+    l = pa_memblock_get_length(b);
+    if (length > l || length == 0)
+        length = l;
+
+    ret->length = pa_frame_align(length, spec);
+    ret->index = 0;
+
+    return ret;
+}
diff --git a/src/pulsecore/sample-util.h b/src/pulsecore/sample-util.h
index 2ef8f924..45f00883 100644
--- a/src/pulsecore/sample-util.h
+++ b/src/pulsecore/sample-util.h
@@ -30,10 +30,18 @@
 #include <pulsecore/memblock.h>
 #include <pulsecore/memchunk.h>
 
-pa_memblock *pa_silence_memblock(pa_memblock* b, const pa_sample_spec *spec);
-pa_memblock *pa_silence_memblock_new(pa_mempool *pool, const pa_sample_spec *spec, size_t length);
-void pa_silence_memchunk(pa_memchunk *c, const pa_sample_spec *spec);
-void pa_silence_memory(void *p, size_t length, const pa_sample_spec *spec);
+typedef struct pa_silence_cache {
+    pa_memblock* blocks[PA_SAMPLE_MAX];
+} pa_silence_cache;
+
+void pa_silence_cache_init(pa_silence_cache *cache);
+void pa_silence_cache_done(pa_silence_cache *cache);
+
+void *pa_silence_memory(void *p, size_t length, const pa_sample_spec *spec);
+pa_memchunk* pa_silence_memchunk(pa_memchunk *c, const pa_sample_spec *spec);
+pa_memblock* pa_silence_memblock(pa_memblock *b, const pa_sample_spec *spec);
+
+pa_memchunk* pa_silence_memchunk_get(pa_silence_cache *cache, pa_mempool *pool, pa_memchunk* ret, const pa_sample_spec *spec, size_t length);
 
 typedef struct pa_mix_info {
     pa_memchunk chunk;