blob: 76edc346690122902abb8bccc4c6676fcaa82eef (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
// Copyright (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This file contains the definition of the IdAllocator class.
#ifndef GPU_COMMAND_BUFFER_CLIENT_ID_ALLOCATOR_H_
#define GPU_COMMAND_BUFFER_CLIENT_ID_ALLOCATOR_H_
#include <set>
#include <utility>
#include "../common/types.h"
namespace gpu {
// A resource ID, key to the resource maps.
typedef uint32 ResourceId;
// Invalid resource ID.
static const ResourceId kInvalidResource = 0u;
// A class to manage the allocation of resource IDs.
class IdAllocator {
public:
IdAllocator();
// Allocates a new resource ID.
ResourceId AllocateID() {
ResourceId id = FindFirstFree();
MarkAsUsed(id);
return id;
}
// Allocates an Id starting at or above desired_id.
// Note: may wrap if it starts near limit.
ResourceId AllocateIDAtOrAbove(ResourceId desired_id);
// Marks an id as used. Returns false if id was already used.
bool MarkAsUsed(ResourceId id) {
std::pair<ResourceIdSet::iterator, bool> result = used_ids_.insert(id);
return result.second;
}
// Frees a resource ID.
void FreeID(ResourceId id) {
used_ids_.erase(id);
}
// Checks whether or not a resource ID is in use.
bool InUse(ResourceId id) const {
return id == kInvalidResource || used_ids_.find(id) != used_ids_.end();
}
private:
// TODO(gman): This would work much better with ranges or a hash table.
typedef std::set<ResourceId> ResourceIdSet;
ResourceId FindFirstFree() const;
ResourceIdSet used_ids_;
DISALLOW_COPY_AND_ASSIGN(IdAllocator);
};
} // namespace gpu
#endif // GPU_COMMAND_BUFFER_CLIENT_ID_ALLOCATOR_H_
|
