content/browser/streams/stream_registry.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/streams/stream_registry.h"
   6
   7 #include "content/browser/streams/stream.h"
   8
   9 namespace content {
  10
  11 namespace {
  12 // The maximum size of memory each StreamRegistry instance is allowed to use
  13 // for its Stream instances.
  14 const size_t kDefaultMaxMemoryUsage = 1024 * 1024 * 1024U;  // 1GiB
  15 }
  16
  17 StreamRegistry::StreamRegistry()
  18     : total_memory_usage_(0),
  19       max_memory_usage_(kDefaultMaxMemoryUsage) {
  20 }
  21
  22 StreamRegistry::~StreamRegistry() {
  23 }
  24
  25 void StreamRegistry::RegisterStream(scoped_refptr<Stream> stream) {
  26   DCHECK(CalledOnValidThread());
  27   DCHECK(stream.get());
  28   DCHECK(!stream->url().is_empty());
  29   streams_[stream->url()] = stream;
  30 }
  31
  32 scoped_refptr<Stream> StreamRegistry::GetStream(const GURL& url) {
  33   DCHECK(CalledOnValidThread());
  34   StreamMap::const_iterator stream = streams_.find(url);
  35   if (stream != streams_.end())
  36     return stream->second;
  37
  38   return NULL;
  39 }
  40
  41 bool StreamRegistry::CloneStream(const GURL& url, const GURL& src_url) {
  42   DCHECK(CalledOnValidThread());
  43   scoped_refptr<Stream> stream(GetStream(src_url));
  44   if (stream.get()) {
  45     streams_[url] = stream;
  46     return true;
  47   }
  48   return false;
  49 }
  50
  51 void StreamRegistry::UnregisterStream(const GURL& url) {
  52   DCHECK(CalledOnValidThread());
  53
  54   StreamMap::iterator iter = streams_.find(url);
  55   if (iter == streams_.end())
  56     return;
  57
  58   // Only update |total_memory_usage_| if |url| is NOT a Stream clone because
  59   // cloned streams do not update |total_memory_usage_|.
  60   if (iter->second->url() == url) {
  61     size_t buffered_bytes = iter->second->last_total_buffered_bytes();
  62     DCHECK_LE(buffered_bytes, total_memory_usage_);
  63     total_memory_usage_ -= buffered_bytes;
  64   }
  65
  66   streams_.erase(url);
  67 }
  68
  69 bool StreamRegistry::UpdateMemoryUsage(const GURL& url,
  70                                        size_t current_size,
  71                                        size_t increase) {
  72   DCHECK(CalledOnValidThread());
  73
  74   StreamMap::iterator iter = streams_.find(url);
  75   // A Stream must be registered with its parent registry to get memory.
  76   if (iter == streams_.end())
  77     return false;
  78
  79   size_t last_size = iter->second->last_total_buffered_bytes();
  80   DCHECK_LE(last_size, total_memory_usage_);
  81   size_t usage_of_others = total_memory_usage_ - last_size;
  82   DCHECK_LE(current_size, last_size);
  83   size_t current_total_memory_usage = usage_of_others + current_size;
  84
  85   if (increase > max_memory_usage_ - current_total_memory_usage)
  86     return false;
  87
  88   total_memory_usage_ = current_total_memory_usage + increase;
  89   return true;
  90 }
  91
  92 }  // namespace content