initial commit

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@3 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/memblockq.c

@@ -0,0 +1,156 @@
+#include <assert.h>
+#include <stdlib.h>
+
+#include "memblockq.h"
+
+struct memblock_list {
+    struct memblock_list *next;
+    struct memchunk chunk;
+};
+
+struct memblockq {
+    struct memblock_list *blocks, *blocks_tail;
+    unsigned n_blocks;
+    size_t total_length;
+    size_t maxlength;
+    size_t base;
+};
+
+struct memblockq* memblockq_new(size_t maxlength, size_t base) {
+    struct memblockq* bq;
+    assert(maxlength && base);
+    
+    bq = malloc(sizeof(struct memblockq));
+    assert(bq);
+    bq->blocks = bq->blocks_tail = 0;
+    bq->n_blocks = 0;
+    bq->total_length = 0;
+    bq->base = base;
+    bq->maxlength = ((maxlength+base-1)/base)*base;
+    assert(bq->maxlength >= base);
+    return bq;
+}
+
+void memblockq_free(struct memblockq* bq) {
+    struct memblock_list *l;
+    assert(bq);
+
+    while ((l = bq->blocks)) {
+        bq->blocks = l->next;
+        memblock_unref(l->chunk.memblock);
+        free(l);
+    }
+    
+    free(bq);
+}
+
+void memblockq_push(struct memblockq* bq, struct memchunk *chunk, size_t delta) {
+    struct memblock_list *q;
+    assert(bq && chunk && chunk->memblock && chunk->index);
+
+    q = malloc(sizeof(struct memblock_list));
+    assert(q);
+
+    q->chunk = *chunk;
+    memblock_ref(q->chunk.memblock);
+    assert(q->chunk.index+q->chunk.length <= q->chunk.memblock->length);
+    q->next = NULL;
+    
+    if (bq->blocks_tail)
+        bq->blocks_tail->next = q;
+    else
+        bq->blocks = q;
+    
+    bq->blocks_tail = q;
+
+    bq->n_blocks++;
+    bq->total_length += chunk->length;
+
+    memblockq_shorten(bq, bq->maxlength);
+}
+
+int memblockq_peek(struct memblockq* bq, struct memchunk *chunk) {
+    assert(bq && chunk);
+
+    if (!bq->blocks)
+        return -1;
+
+    *chunk = bq->blocks->chunk;
+    memblock_ref(chunk->memblock);
+    return 0;
+}
+
+int memblockq_pop(struct memblockq* bq, struct memchunk *chunk) {
+    struct memblock_list *q;
+    
+    assert(bq && chunk);
+
+    if (!bq->blocks)
+        return -1;
+
+    q = bq->blocks;
+    bq->blocks = bq->blocks->next;
+
+    *chunk = q->chunk;
+
+    bq->n_blocks--;
+    bq->total_length -= chunk->length;
+
+    free(q);
+    return 0;
+}
+
+void memblockq_drop(struct memblockq *bq, size_t length) {
+    assert(bq);
+
+    while (length > 0) {
+        size_t l = length;
+        assert(bq->blocks && bq->total_length >= length);
+        
+        if (l > bq->blocks->chunk.length)
+            l = bq->blocks->chunk.length;
+    
+        bq->blocks->chunk.index += l;
+        bq->blocks->chunk.length -= l;
+        bq->total_length -= l;
+        
+        if (bq->blocks->chunk.length == 0) {
+            struct memblock_list *q;
+            
+            q = bq->blocks;
+            bq->blocks = bq->blocks->next;
+            memblock_unref(q->chunk.memblock);
+            free(q);
+            
+            bq->n_blocks--;
+        }
+
+        length -= l;
+    }
+}
+
+void memblockq_shorten(struct memblockq *bq, size_t length) {
+    size_t l;
+    assert(bq);
+
+    if (bq->total_length <= length)
+        return;
+
+    l = bq->total_length - length;
+    l /= bq->base;
+    l *= bq->base;
+
+    memblockq_drop(bq, l);
+}
+
+
+void memblockq_empty(struct memblockq *bq) {
+    assert(bq);
+    memblockq_shorten(bq, 0);
+}
+
+int memblockq_is_empty(struct memblockq *bq) {
+    assert(bq);
+
+    return bq->total_length >= bq->base;
+}