GCC Code Coverage Report

Directory: cvmfs/
File: cvmfs/bigqueue.h
Date: 2026-10-11 02:40:02
Exec Total Coverage
Lines: 76 77 98.7%
Branches: 23 32 71.9%
Line Branch Exec Source
1 /**
2 * This file is part of the CernVM File System.
3 *
4 * Similar to bigvector, but queue semantics. Used by the negative entry
5 * tracker. Allocates with mmap in order to avoid memory fragmentation.
6 */
7
8 #ifndef CVMFS_BIGQUEUE_H_
9 #define CVMFS_BIGQUEUE_H_
10
11 #include <algorithm>
12 #include <cassert>
13 #include <cstdlib>
14 #include <new>
15
16 #include "util/smalloc.h"
17
18 template<class Item>
19 class BigQueue {
20 public:
21 642 BigQueue() {
22 642 Alloc(kNumInit);
23 642 size_ = 0;
24 642 }
25
26 explicit BigQueue(const size_t num_items) {
27 const size_t min_items = kNumInit;
28 Alloc(std::max(num_items, min_items));
29 size_ = 0;
30 }
31
32 19 BigQueue(const BigQueue<Item> &other) { CopyFrom(other); }
33
34 9 BigQueue<Item> &operator=(const BigQueue<Item> &other) {
35
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 9 times.
 9 if (&other == this)
36 ✗ return *this;
37
38 9 Dealloc();
39 9 CopyFrom(other);
40 9 return *this;
41 }
42
43 655 ~BigQueue() { Dealloc(); }
44
45 380040068 void PushBack(const Item &item) {
46
2/2
✓ Branch 1 taken 922 times.
✓ Branch 2 taken 380039146 times.
 380040068 if (GetAvailableSpace() == 0) {
47 922 Migrate(1.9 * static_cast<float>(capacity_));
48
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 922 times.
 922 assert(GetAvailableSpace() > 0);
49 }
50
1/2
✓ Branch 2 taken 2068 times.
✗ Branch 3 not taken.
 380040068 new (head_ + size_) Item(item);
51 380040068 size_++;
52 380040068 }
53
54 380028514 void PopFront() {
55
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 380028514 times.
 380028514 assert(!IsEmpty());
56 380028514 head_++;
57 380028514 size_--;
58
4/4
✓ Branch 0 taken 380024795 times.
✓ Branch 1 taken 3719 times.
✓ Branch 2 taken 969 times.
✓ Branch 3 taken 380023826 times.
 380028514 if ((size_ > kCompactThreshold) && (size_ < (capacity_ / 2)))
59 969 Migrate(static_cast<int>(static_cast<float>(capacity_ * 0.6)));
60 380028514 }
61
62 380030707 bool Peek(Item **item) {
63
2/2
✓ Branch 1 taken 105 times.
✓ Branch 2 taken 380030602 times.
 380030707 if (IsEmpty())
64 105 return false;
65 380030602 *item = head_;
66 380030602 return true;
67 }
68
69 760059221 bool IsEmpty() const { return size_ == 0; }
70
71 9 void Clear() {
72 9 Dealloc();
73 9 Alloc(kNumInit);
74 9 }
75
76 1751 size_t size() const { return size_; }
77 190 size_t capacity() const { return capacity_; }
78
79 private:
80 static const size_t kNumInit = 64;
81 static const size_t kCompactThreshold = 64;
82
83 475045608 size_t GetHeadOffset() const { return head_ - buffer_; }
84 380040990 size_t GetAvailableSpace() const {
85 380040990 return capacity_ - (size_ + GetHeadOffset());
86 }
87
88 2570 void Alloc(const size_t num_elements) {
89 2570 size_t const num_bytes = sizeof(Item) * num_elements;
90 2570 buffer_ = static_cast<Item *>(smmap(num_bytes));
91 2570 capacity_ = num_elements;
92 2570 head_ = buffer_;
93 2570 }
94
95 673 void Dealloc() {
96 673 FreeBuffer(buffer_, GetHeadOffset() + size_);
97 673 buffer_ = NULL;
98 673 head_ = NULL;
99 673 capacity_ = 0;
100 673 size_ = 0;
101 673 }
102
103 1891 void Migrate(size_t new_capacity) {
104
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 1891 times.
 1891 assert(new_capacity > 0);
105
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 1891 times.
 1891 assert(new_capacity >= size_);
106
107 1891 size_t const head_offset = GetHeadOffset();
108 1891 Item *old_buffer = buffer_;
109
110 1891 Alloc(new_capacity);
111
2/2
✓ Branch 0 taken 1064716857 times.
✓ Branch 1 taken 1891 times.
 1064718748 for (size_t i = 0; i < size_; ++i)
112
1/2
✓ Branch 2 taken 3350 times.
✗ Branch 3 not taken.
 1064716857 new (buffer_ + i) Item(old_buffer[head_offset + i]);
113
114 1891 FreeBuffer(old_buffer, head_offset + size_);
115 1891 }
116
117 2564 void FreeBuffer(Item *buf, const size_t nitems) {
118
2/2
✓ Branch 0 taken 1539758973 times.
✓ Branch 1 taken 2564 times.
 1539761537 for (size_t i = 0; i < nitems; ++i)
119 1539758973 buf[i].~Item();
120
121
1/2
✓ Branch 0 taken 2564 times.
✗ Branch 1 not taken.
 2564 if (buf)
122 2564 smunmap(buf);
123 2564 }
124
125 28 void CopyFrom(const BigQueue<Item> &other) {
126 28 size_t const min_items = kNumInit;
127 28 Alloc(std::max(other.size_, min_items));
128
2/2
✓ Branch 0 taken 95002054 times.
✓ Branch 1 taken 28 times.
 95002082 for (size_t i = 0; i < other.size_; ++i) {
129
1/2
✓ Branch 3 taken 2054 times.
✗ Branch 4 not taken.
 95002054 new (buffer_ + i) Item(*(other.buffer_ + other.GetHeadOffset() + i));
130 }
131 28 size_ = other.size_;
132 28 }
133
134 Item *buffer_;
135 Item *head_;
136 size_t size_;
137 size_t capacity_;
138 };
139
140 #endif // CVMFS_BIGQUEUE_H_
141